fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1

Signed-off-by: Anton Arapov <anton@redhat.com>

253 files changed, 188133 insertions, 0 deletions

diff --git a/kernel/Kconfig.freezer b/kernel/Kconfig.freezer
new file mode 100644
index 00000000000..a3bb4cb5253
--- /dev/null
+++ b/kernel/Kconfig.freezer
@@ -0,0 +1,2 @@
+config FREEZER
+	def_bool PM_SLEEP || CGROUP_FREEZER
diff --git a/kernel/Kconfig.hz b/kernel/Kconfig.hz
new file mode 100644
index 00000000000..94fabd534b0
--- /dev/null
+++ b/kernel/Kconfig.hz
@@ -0,0 +1,58 @@
+#
+# Timer Interrupt Frequency Configuration
+#
+
+choice
+	prompt "Timer frequency"
+	default HZ_250
+	help
+	 Allows the configuration of the timer frequency. It is customary
+	 to have the timer interrupt run at 1000 Hz but 100 Hz may be more
+	 beneficial for servers and NUMA systems that do not need to have
+	 a fast response for user interaction and that may experience bus
+	 contention and cacheline bounces as a result of timer interrupts.
+	 Note that the timer interrupt occurs on each processor in an SMP
+	 environment leading to NR_CPUS * HZ number of timer interrupts
+	 per second.
+
+
+	config HZ_100
+		bool "100 HZ"
+	help
+	  100 Hz is a typical choice for servers, SMP and NUMA systems
+	  with lots of processors that may show reduced performance if
+	  too many timer interrupts are occurring.
+
+	config HZ_250
+		bool "250 HZ"
+	help
+	 250 Hz is a good compromise choice allowing server performance
+	 while also showing good interactive responsiveness even
+	 on SMP and NUMA systems. If you are going to be using NTSC video
+	 or multimedia, selected 300Hz instead.
+
+	config HZ_300
+		bool "300 HZ"
+	help
+	 300 Hz is a good compromise choice allowing server performance
+	 while also showing good interactive responsiveness even
+	 on SMP and NUMA systems and exactly dividing by both PAL and
+	 NTSC frame rates for video and multimedia work.
+
+	config HZ_1000
+		bool "1000 HZ"
+	help
+	 1000 Hz is the preferred choice for desktop systems and other
+	 systems requiring fast interactive responses to events.
+
+endchoice
+
+config HZ
+	int
+	default 100 if HZ_100
+	default 250 if HZ_250
+	default 300 if HZ_300
+	default 1000 if HZ_1000
+
+config SCHED_HRTICK
+	def_bool HIGH_RES_TIMERS && (!SMP || USE_GENERIC_SMP_HELPERS)
diff --git a/kernel/Kconfig.locks b/kernel/Kconfig.locks
new file mode 100644
index 00000000000..5068e2a4e75
--- /dev/null
+++ b/kernel/Kconfig.locks
@@ -0,0 +1,202 @@
+#
+# The ARCH_INLINE foo is necessary because select ignores "depends on"
+#
+config ARCH_INLINE_SPIN_TRYLOCK
+	bool
+
+config ARCH_INLINE_SPIN_TRYLOCK_BH
+	bool
+
+config ARCH_INLINE_SPIN_LOCK
+	bool
+
+config ARCH_INLINE_SPIN_LOCK_BH
+	bool
+
+config ARCH_INLINE_SPIN_LOCK_IRQ
+	bool
+
+config ARCH_INLINE_SPIN_LOCK_IRQSAVE
+	bool
+
+config ARCH_INLINE_SPIN_UNLOCK
+	bool
+
+config ARCH_INLINE_SPIN_UNLOCK_BH
+	bool
+
+config ARCH_INLINE_SPIN_UNLOCK_IRQ
+	bool
+
+config ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
+	bool
+
+
+config ARCH_INLINE_READ_TRYLOCK
+	bool
+
+config ARCH_INLINE_READ_LOCK
+	bool
+
+config ARCH_INLINE_READ_LOCK_BH
+	bool
+
+config ARCH_INLINE_READ_LOCK_IRQ
+	bool
+
+config ARCH_INLINE_READ_LOCK_IRQSAVE
+	bool
+
+config ARCH_INLINE_READ_UNLOCK
+	bool
+
+config ARCH_INLINE_READ_UNLOCK_BH
+	bool
+
+config ARCH_INLINE_READ_UNLOCK_IRQ
+	bool
+
+config ARCH_INLINE_READ_UNLOCK_IRQRESTORE
+	bool
+
+
+config ARCH_INLINE_WRITE_TRYLOCK
+	bool
+
+config ARCH_INLINE_WRITE_LOCK
+	bool
+
+config ARCH_INLINE_WRITE_LOCK_BH
+	bool
+
+config ARCH_INLINE_WRITE_LOCK_IRQ
+	bool
+
+config ARCH_INLINE_WRITE_LOCK_IRQSAVE
+	bool
+
+config ARCH_INLINE_WRITE_UNLOCK
+	bool
+
+config ARCH_INLINE_WRITE_UNLOCK_BH
+	bool
+
+config ARCH_INLINE_WRITE_UNLOCK_IRQ
+	bool
+
+config ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
+	bool
+
+#
+# lock_* functions are inlined when:
+#   - DEBUG_SPINLOCK=n and GENERIC_LOCKBREAK=n and ARCH_INLINE_*LOCK=y
+#
+# trylock_* functions are inlined when:
+#   - DEBUG_SPINLOCK=n and ARCH_INLINE_*LOCK=y
+#
+# unlock and unlock_irq functions are inlined when:
+#   - DEBUG_SPINLOCK=n and ARCH_INLINE_*LOCK=y
+#  or
+#   - DEBUG_SPINLOCK=n and PREEMPT=n
+#
+# unlock_bh and unlock_irqrestore functions are inlined when:
+#   - DEBUG_SPINLOCK=n and ARCH_INLINE_*LOCK=y
+#
+
+config INLINE_SPIN_TRYLOCK
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_TRYLOCK
+
+config INLINE_SPIN_TRYLOCK_BH
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_TRYLOCK_BH
+
+config INLINE_SPIN_LOCK
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && ARCH_INLINE_SPIN_LOCK
+
+config INLINE_SPIN_LOCK_BH
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_SPIN_LOCK_BH
+
+config INLINE_SPIN_LOCK_IRQ
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_SPIN_LOCK_IRQ
+
+config INLINE_SPIN_LOCK_IRQSAVE
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_SPIN_LOCK_IRQSAVE
+
+config INLINE_SPIN_UNLOCK
+	def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_SPIN_UNLOCK)
+
+config INLINE_SPIN_UNLOCK_BH
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_UNLOCK_BH
+
+config INLINE_SPIN_UNLOCK_IRQ
+	def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_SPIN_UNLOCK_BH)
+
+config INLINE_SPIN_UNLOCK_IRQRESTORE
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
+
+
+config INLINE_READ_TRYLOCK
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_READ_TRYLOCK
+
+config INLINE_READ_LOCK
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && ARCH_INLINE_READ_LOCK
+
+config INLINE_READ_LOCK_BH
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_READ_LOCK_BH
+
+config INLINE_READ_LOCK_IRQ
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_READ_LOCK_IRQ
+
+config INLINE_READ_LOCK_IRQSAVE
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_READ_LOCK_IRQSAVE
+
+config INLINE_READ_UNLOCK
+	def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_READ_UNLOCK)
+
+config INLINE_READ_UNLOCK_BH
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_READ_UNLOCK_BH
+
+config INLINE_READ_UNLOCK_IRQ
+	def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_READ_UNLOCK_BH)
+
+config INLINE_READ_UNLOCK_IRQRESTORE
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_READ_UNLOCK_IRQRESTORE
+
+
+config INLINE_WRITE_TRYLOCK
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_TRYLOCK
+
+config INLINE_WRITE_LOCK
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && ARCH_INLINE_WRITE_LOCK
+
+config INLINE_WRITE_LOCK_BH
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_WRITE_LOCK_BH
+
+config INLINE_WRITE_LOCK_IRQ
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_WRITE_LOCK_IRQ
+
+config INLINE_WRITE_LOCK_IRQSAVE
+	def_bool !DEBUG_SPINLOCK && !GENERIC_LOCKBREAK && \
+		 ARCH_INLINE_WRITE_LOCK_IRQSAVE
+
+config INLINE_WRITE_UNLOCK
+	def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_WRITE_UNLOCK)
+
+config INLINE_WRITE_UNLOCK_BH
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_UNLOCK_BH
+
+config INLINE_WRITE_UNLOCK_IRQ
+	def_bool !DEBUG_SPINLOCK && (!PREEMPT || ARCH_INLINE_WRITE_UNLOCK_BH)
+
+config INLINE_WRITE_UNLOCK_IRQRESTORE
+	def_bool !DEBUG_SPINLOCK && ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
+
+config MUTEX_SPIN_ON_OWNER
+	def_bool SMP && !DEBUG_MUTEXES
diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt
new file mode 100644
index 00000000000..24e7cb0ba26
--- /dev/null
+++ b/kernel/Kconfig.preempt
@@ -0,0 +1,57 @@
+
+choice
+	prompt "Preemption Model"
+	default PREEMPT_NONE
+
+config PREEMPT_NONE
+	bool "No Forced Preemption (Server)"
+	help
+	  This is the traditional Linux preemption model, geared towards
+	  throughput. It will still provide good latencies most of the
+	  time, but there are no guarantees and occasional longer delays
+	  are possible.
+
+	  Select this option if you are building a kernel for a server or
+	  scientific/computation system, or if you want to maximize the
+	  raw processing power of the kernel, irrespective of scheduling
+	  latencies.
+
+config PREEMPT_VOLUNTARY
+	bool "Voluntary Kernel Preemption (Desktop)"
+	help
+	  This option reduces the latency of the kernel by adding more
+	  "explicit preemption points" to the kernel code. These new
+	  preemption points have been selected to reduce the maximum
+	  latency of rescheduling, providing faster application reactions,
+	  at the cost of slightly lower throughput.
+
+	  This allows reaction to interactive events by allowing a
+	  low priority process to voluntarily preempt itself even if it
+	  is in kernel mode executing a system call. This allows
+	  applications to run more 'smoothly' even when the system is
+	  under load.
+
+	  Select this if you are building a kernel for a desktop system.
+
+config PREEMPT
+	bool "Preemptible Kernel (Low-Latency Desktop)"
+	select PREEMPT_COUNT
+	help
+	  This option reduces the latency of the kernel by making
+	  all kernel code (that is not executing in a critical section)
+	  preemptible.  This allows reaction to interactive events by
+	  permitting a low priority process to be preempted involuntarily
+	  even if it is in kernel mode executing a system call and would
+	  otherwise not be about to reach a natural preemption point.
+	  This allows applications to run more 'smoothly' even when the
+	  system is under load, at the cost of slightly lower throughput
+	  and a slight runtime overhead to kernel code.
+
+	  Select this if you are building a kernel for a desktop or
+	  embedded system with latency requirements in the milliseconds
+	  range.
+
+endchoice
+
+config PREEMPT_COUNT
+       bool
\ No newline at end of file
diff --git a/kernel/Makefile b/kernel/Makefile
new file mode 100644
index 00000000000..2d9de86b7e7
--- /dev/null
+++ b/kernel/Makefile
@@ -0,0 +1,130 @@
+#
+# Makefile for the linux kernel.
+#
+
+obj-y     = fork.o exec_domain.o panic.o printk.o \
+	    cpu.o exit.o itimer.o time.o softirq.o resource.o \
+	    sysctl.o sysctl_binary.o capability.o ptrace.o timer.o user.o \
+	    signal.o sys.o kmod.o workqueue.o pid.o \
+	    rcupdate.o extable.o params.o posix-timers.o \
+	    kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
+	    hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
+	    notifier.o ksysfs.o cred.o \
+	    async.o range.o groups.o
+
+ifdef CONFIG_FUNCTION_TRACER
+# Do not trace debug files and internal ftrace files
+CFLAGS_REMOVE_lockdep.o = -pg
+CFLAGS_REMOVE_lockdep_proc.o = -pg
+CFLAGS_REMOVE_mutex-debug.o = -pg
+CFLAGS_REMOVE_rtmutex-debug.o = -pg
+CFLAGS_REMOVE_cgroup-debug.o = -pg
+CFLAGS_REMOVE_irq_work.o = -pg
+endif
+
+obj-y += sched/
+obj-y += power/
+
+obj-$(CONFIG_FREEZER) += freezer.o
+obj-$(CONFIG_PROFILING) += profile.o
+obj-$(CONFIG_SYSCTL_SYSCALL_CHECK) += sysctl_check.o
+obj-$(CONFIG_STACKTRACE) += stacktrace.o
+obj-y += time/
+obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
+obj-$(CONFIG_LOCKDEP) += lockdep.o
+ifeq ($(CONFIG_PROC_FS),y)
+obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
+endif
+obj-$(CONFIG_FUTEX) += futex.o
+ifeq ($(CONFIG_COMPAT),y)
+obj-$(CONFIG_FUTEX) += futex_compat.o
+endif
+obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
+obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
+obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o
+obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
+obj-$(CONFIG_SMP) += smp.o
+ifneq ($(CONFIG_SMP),y)
+obj-y += up.o
+endif
+obj-$(CONFIG_SMP) += spinlock.o
+obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
+obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
+obj-$(CONFIG_UID16) += uid16.o
+obj-$(CONFIG_MODULES) += module.o
+obj-$(CONFIG_KALLSYMS) += kallsyms.o
+obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
+obj-$(CONFIG_KEXEC) += kexec.o
+obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o
+obj-$(CONFIG_COMPAT) += compat.o
+obj-$(CONFIG_CGROUPS) += cgroup.o
+obj-$(CONFIG_CGROUP_FREEZER) += cgroup_freezer.o
+obj-$(CONFIG_CPUSETS) += cpuset.o
+obj-$(CONFIG_UTS_NS) += utsname.o
+obj-$(CONFIG_USER_NS) += user_namespace.o
+obj-$(CONFIG_PID_NS) += pid_namespace.o
+obj-$(CONFIG_IKCONFIG) += configs.o
+obj-$(CONFIG_RESOURCE_COUNTERS) += res_counter.o
+obj-$(CONFIG_SMP) += stop_machine.o
+obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
+obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
+obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
+obj-$(CONFIG_AUDIT_WATCH) += audit_watch.o
+obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
+obj-$(CONFIG_GCOV_KERNEL) += gcov/
+obj-$(CONFIG_KPROBES) += kprobes.o
+obj-$(CONFIG_KGDB) += debug/
+obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o
+obj-$(CONFIG_LOCKUP_DETECTOR) += watchdog.o
+obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
+obj-$(CONFIG_SECCOMP) += seccomp.o
+obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o
+obj-$(CONFIG_TREE_RCU) += rcutree.o
+obj-$(CONFIG_TREE_PREEMPT_RCU) += rcutree.o
+obj-$(CONFIG_TREE_RCU_TRACE) += rcutree_trace.o
+obj-$(CONFIG_TINY_RCU) += rcutiny.o
+obj-$(CONFIG_TINY_PREEMPT_RCU) += rcutiny.o
+obj-$(CONFIG_RELAY) += relay.o
+obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
+obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
+obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
+obj-$(CONFIG_TRACEPOINTS) += tracepoint.o
+obj-$(CONFIG_LATENCYTOP) += latencytop.o
+obj-$(CONFIG_BINFMT_ELF) += elfcore.o
+obj-$(CONFIG_COMPAT_BINFMT_ELF) += elfcore.o
+obj-$(CONFIG_BINFMT_ELF_FDPIC) += elfcore.o
+obj-$(CONFIG_FUNCTION_TRACER) += trace/
+obj-$(CONFIG_TRACING) += trace/
+obj-$(CONFIG_X86_DS) += trace/
+obj-$(CONFIG_RING_BUFFER) += trace/
+obj-$(CONFIG_TRACEPOINTS) += trace/
+obj-$(CONFIG_IRQ_WORK) += irq_work.o
+obj-$(CONFIG_CPU_PM) += cpu_pm.o
+
+obj-$(CONFIG_PERF_EVENTS) += events/
+
+obj-$(CONFIG_USER_RETURN_NOTIFIER) += user-return-notifier.o
+obj-$(CONFIG_PADATA) += padata.o
+obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
+obj-$(CONFIG_JUMP_LABEL) += jump_label.o
+
+$(obj)/configs.o: $(obj)/config_data.h
+
+# config_data.h contains the same information as ikconfig.h but gzipped.
+# Info from config_data can be extracted from /proc/config*
+targets += config_data.gz
+$(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE
+	$(call if_changed,gzip)
+
+      filechk_ikconfiggz = (echo "static const char kernel_config_data[] __used = MAGIC_START"; cat $< | scripts/bin2c; echo "MAGIC_END;")
+targets += config_data.h
+$(obj)/config_data.h: $(obj)/config_data.gz FORCE
+	$(call filechk,ikconfiggz)
+
+$(obj)/time.o: $(obj)/timeconst.h
+
+quiet_cmd_timeconst  = TIMEC   $@
+      cmd_timeconst  = $(PERL) $< $(CONFIG_HZ) > $@
+targets += timeconst.h
+$(obj)/timeconst.h: $(src)/timeconst.pl FORCE
+	$(call if_changed,timeconst)
diff --git a/kernel/acct.c b/kernel/acct.c
new file mode 100644
index 00000000000..02e6167a53b
--- /dev/null
+++ b/kernel/acct.c
@@ -0,0 +1,645 @@
+/*
+ *  linux/kernel/acct.c
+ *
+ *  BSD Process Accounting for Linux
+ *
+ *  Author: Marco van Wieringen <mvw@planets.elm.net>
+ *
+ *  Some code based on ideas and code from:
+ *  Thomas K. Dyas <tdyas@eden.rutgers.edu>
+ *
+ *  This file implements BSD-style process accounting. Whenever any
+ *  process exits, an accounting record of type "struct acct" is
+ *  written to the file specified with the acct() system call. It is
+ *  up to user-level programs to do useful things with the accounting
+ *  log. The kernel just provides the raw accounting information.
+ *
+ * (C) Copyright 1995 - 1997 Marco van Wieringen - ELM Consultancy B.V.
+ *
+ *  Plugged two leaks. 1) It didn't return acct_file into the free_filps if
+ *  the file happened to be read-only. 2) If the accounting was suspended
+ *  due to the lack of space it happily allowed to reopen it and completely
+ *  lost the old acct_file. 3/10/98, Al Viro.
+ *
+ *  Now we silently close acct_file on attempt to reopen. Cleaned sys_acct().
+ *  XTerms and EMACS are manifestations of pure evil. 21/10/98, AV.
+ *
+ *  Fixed a nasty interaction with with sys_umount(). If the accointing
+ *  was suspeneded we failed to stop it on umount(). Messy.
+ *  Another one: remount to readonly didn't stop accounting.
+ *	Question: what should we do if we have CAP_SYS_ADMIN but not
+ *  CAP_SYS_PACCT? Current code does the following: umount returns -EBUSY
+ *  unless we are messing with the root. In that case we are getting a
+ *  real mess with do_remount_sb(). 9/11/98, AV.
+ *
+ *  Fixed a bunch of races (and pair of leaks). Probably not the best way,
+ *  but this one obviously doesn't introduce deadlocks. Later. BTW, found
+ *  one race (and leak) in BSD implementation.
+ *  OK, that's better. ANOTHER race and leak in BSD variant. There always
+ *  is one more bug... 10/11/98, AV.
+ *
+ *	Oh, fsck... Oopsable SMP race in do_process_acct() - we must hold
+ * ->mmap_sem to walk the vma list of current->mm. Nasty, since it leaks
+ * a struct file opened for write. Fixed. 2/6/2000, AV.
+ */
+
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/acct.h>
+#include <linux/capability.h>
+#include <linux/file.h>
+#include <linux/tty.h>
+#include <linux/security.h>
+#include <linux/vfs.h>
+#include <linux/jiffies.h>
+#include <linux/times.h>
+#include <linux/syscalls.h>
+#include <linux/mount.h>
+#include <asm/uaccess.h>
+#include <asm/div64.h>
+#include <linux/blkdev.h> /* sector_div */
+#include <linux/pid_namespace.h>
+
+/*
+ * These constants control the amount of freespace that suspend and
+ * resume the process accounting system, and the time delay between
+ * each check.
+ * Turned into sysctl-controllable parameters. AV, 12/11/98
+ */
+
+int acct_parm[3] = {4, 2, 30};
+#define RESUME		(acct_parm[0])	/* >foo% free space - resume */
+#define SUSPEND		(acct_parm[1])	/* <foo% free space - suspend */
+#define ACCT_TIMEOUT	(acct_parm[2])	/* foo second timeout between checks */
+
+/*
+ * External references and all of the globals.
+ */
+static void do_acct_process(struct bsd_acct_struct *acct,
+		struct pid_namespace *ns, struct file *);
+
+/*
+ * This structure is used so that all the data protected by lock
+ * can be placed in the same cache line as the lock.  This primes
+ * the cache line to have the data after getting the lock.
+ */
+struct bsd_acct_struct {
+	int			active;
+	unsigned long		needcheck;
+	struct file		*file;
+	struct pid_namespace	*ns;
+	struct list_head	list;
+};
+
+static DEFINE_SPINLOCK(acct_lock);
+static LIST_HEAD(acct_list);
+
+/*
+ * Check the amount of free space and suspend/resume accordingly.
+ */
+static int check_free_space(struct bsd_acct_struct *acct, struct file *file)
+{
+	struct kstatfs sbuf;
+	int res;
+	int act;
+	u64 resume;
+	u64 suspend;
+
+	spin_lock(&acct_lock);
+	res = acct->active;
+	if (!file || time_is_before_jiffies(acct->needcheck))
+		goto out;
+	spin_unlock(&acct_lock);
+
+	/* May block */
+	if (vfs_statfs(&file->f_path, &sbuf))
+		return res;
+	suspend = sbuf.f_blocks * SUSPEND;
+	resume = sbuf.f_blocks * RESUME;
+
+	do_div(suspend, 100);
+	do_div(resume, 100);
+
+	if (sbuf.f_bavail <= suspend)
+		act = -1;
+	else if (sbuf.f_bavail >= resume)
+		act = 1;
+	else
+		act = 0;
+
+	/*
+	 * If some joker switched acct->file under us we'ld better be
+	 * silent and _not_ touch anything.
+	 */
+	spin_lock(&acct_lock);
+	if (file != acct->file) {
+		if (act)
+			res = act>0;
+		goto out;
+	}
+
+	if (acct->active) {
+		if (act < 0) {
+			acct->active = 0;
+			printk(KERN_INFO "Process accounting paused\n");
+		}
+	} else {
+		if (act > 0) {
+			acct->active = 1;
+			printk(KERN_INFO "Process accounting resumed\n");
+		}
+	}
+
+	acct->needcheck = jiffies + ACCT_TIMEOUT*HZ;
+	res = acct->active;
+out:
+	spin_unlock(&acct_lock);
+	return res;
+}
+
+/*
+ * Close the old accounting file (if currently open) and then replace
+ * it with file (if non-NULL).
+ *
+ * NOTE: acct_lock MUST be held on entry and exit.
+ */
+static void acct_file_reopen(struct bsd_acct_struct *acct, struct file *file,
+		struct pid_namespace *ns)
+{
+	struct file *old_acct = NULL;
+	struct pid_namespace *old_ns = NULL;
+
+	if (acct->file) {
+		old_acct = acct->file;
+		old_ns = acct->ns;
+		acct->active = 0;
+		acct->file = NULL;
+		acct->ns = NULL;
+		list_del(&acct->list);
+	}
+	if (file) {
+		acct->file = file;
+		acct->ns = ns;
+		acct->needcheck = jiffies + ACCT_TIMEOUT*HZ;
+		acct->active = 1;
+		list_add(&acct->list, &acct_list);
+	}
+	if (old_acct) {
+		mnt_unpin(old_acct->f_path.mnt);
+		spin_unlock(&acct_lock);
+		do_acct_process(acct, old_ns, old_acct);
+		filp_close(old_acct, NULL);
+		spin_lock(&acct_lock);
+	}
+}
+
+static int acct_on(char *name)
+{
+	struct file *file;
+	struct vfsmount *mnt;
+	struct pid_namespace *ns;
+	struct bsd_acct_struct *acct = NULL;
+
+	/* Difference from BSD - they don't do O_APPEND */
+	file = filp_open(name, O_WRONLY|O_APPEND|O_LARGEFILE, 0);
+	if (IS_ERR(file))
+		return PTR_ERR(file);
+
+	if (!S_ISREG(file->f_path.dentry->d_inode->i_mode)) {
+		filp_close(file, NULL);
+		return -EACCES;
+	}
+
+	if (!file->f_op->write) {
+		filp_close(file, NULL);
+		return -EIO;
+	}
+
+	ns = task_active_pid_ns(current);
+	if (ns->bacct == NULL) {
+		acct = kzalloc(sizeof(struct bsd_acct_struct), GFP_KERNEL);
+		if (acct == NULL) {
+			filp_close(file, NULL);
+			return -ENOMEM;
+		}
+	}
+
+	spin_lock(&acct_lock);
+	if (ns->bacct == NULL) {
+		ns->bacct = acct;
+		acct = NULL;
+	}
+
+	mnt = file->f_path.mnt;
+	mnt_pin(mnt);
+	acct_file_reopen(ns->bacct, file, ns);
+	spin_unlock(&acct_lock);
+
+	mntput(mnt); /* it's pinned, now give up active reference */
+	kfree(acct);
+
+	return 0;
+}
+
+/**
+ * sys_acct - enable/disable process accounting
+ * @name: file name for accounting records or NULL to shutdown accounting
+ *
+ * Returns 0 for success or negative errno values for failure.
+ *
+ * sys_acct() is the only system call needed to implement process
+ * accounting. It takes the name of the file where accounting records
+ * should be written. If the filename is NULL, accounting will be
+ * shutdown.
+ */
+SYSCALL_DEFINE1(acct, const char __user *, name)
+{
+	int error = 0;
+
+	if (!capable(CAP_SYS_PACCT))
+		return -EPERM;
+
+	if (name) {
+		char *tmp = getname(name);
+		if (IS_ERR(tmp))
+			return (PTR_ERR(tmp));
+		error = acct_on(tmp);
+		putname(tmp);
+	} else {
+		struct bsd_acct_struct *acct;
+
+		acct = task_active_pid_ns(current)->bacct;
+		if (acct == NULL)
+			return 0;
+
+		spin_lock(&acct_lock);
+		acct_file_reopen(acct, NULL, NULL);
+		spin_unlock(&acct_lock);
+	}
+
+	return error;
+}
+
+/**
+ * acct_auto_close - turn off a filesystem's accounting if it is on
+ * @m: vfsmount being shut down
+ *
+ * If the accounting is turned on for a file in the subtree pointed to
+ * to by m, turn accounting off.  Done when m is about to die.
+ */
+void acct_auto_close_mnt(struct vfsmount *m)
+{
+	struct bsd_acct_struct *acct;
+
+	spin_lock(&acct_lock);
+restart:
+	list_for_each_entry(acct, &acct_list, list)
+		if (acct->file && acct->file->f_path.mnt == m) {
+			acct_file_reopen(acct, NULL, NULL);
+			goto restart;
+		}
+	spin_unlock(&acct_lock);
+}
+
+/**
+ * acct_auto_close - turn off a filesystem's accounting if it is on
+ * @sb: super block for the filesystem
+ *
+ * If the accounting is turned on for a file in the filesystem pointed
+ * to by sb, turn accounting off.
+ */
+void acct_auto_close(struct super_block *sb)
+{
+	struct bsd_acct_struct *acct;
+
+	spin_lock(&acct_lock);
+restart:
+	list_for_each_entry(acct, &acct_list, list)
+		if (acct->file && acct->file->f_path.dentry->d_sb == sb) {
+			acct_file_reopen(acct, NULL, NULL);
+			goto restart;
+		}
+	spin_unlock(&acct_lock);
+}
+
+void acct_exit_ns(struct pid_namespace *ns)
+{
+	struct bsd_acct_struct *acct = ns->bacct;
+
+	if (acct == NULL)
+		return;
+
+	spin_lock(&acct_lock);
+	if (acct->file != NULL)
+		acct_file_reopen(acct, NULL, NULL);
+	spin_unlock(&acct_lock);
+
+	kfree(acct);
+}
+
+/*
+ *  encode an unsigned long into a comp_t
+ *
+ *  This routine has been adopted from the encode_comp_t() function in
+ *  the kern_acct.c file of the FreeBSD operating system. The encoding
+ *  is a 13-bit fraction with a 3-bit (base 8) exponent.
+ */
+
+#define	MANTSIZE	13			/* 13 bit mantissa. */
+#define	EXPSIZE		3			/* Base 8 (3 bit) exponent. */
+#define	MAXFRACT	((1 << MANTSIZE) - 1)	/* Maximum fractional value. */
+
+static comp_t encode_comp_t(unsigned long value)
+{
+	int exp, rnd;
+
+	exp = rnd = 0;
+	while (value > MAXFRACT) {
+		rnd = value & (1 << (EXPSIZE - 1));	/* Round up? */
+		value >>= EXPSIZE;	/* Base 8 exponent == 3 bit shift. */
+		exp++;
+	}
+
+	/*
+	 * If we need to round up, do it (and handle overflow correctly).
+	 */
+	if (rnd && (++value > MAXFRACT)) {
+		value >>= EXPSIZE;
+		exp++;
+	}
+
+	/*
+	 * Clean it up and polish it off.
+	 */
+	exp <<= MANTSIZE;		/* Shift the exponent into place */
+	exp += value;			/* and add on the mantissa. */
+	return exp;
+}
+
+#if ACCT_VERSION==1 || ACCT_VERSION==2
+/*
+ * encode an u64 into a comp2_t (24 bits)
+ *
+ * Format: 5 bit base 2 exponent, 20 bits mantissa.
+ * The leading bit of the mantissa is not stored, but implied for
+ * non-zero exponents.
+ * Largest encodable value is 50 bits.
+ */
+
+#define MANTSIZE2       20                      /* 20 bit mantissa. */
+#define EXPSIZE2        5                       /* 5 bit base 2 exponent. */
+#define MAXFRACT2       ((1ul << MANTSIZE2) - 1) /* Maximum fractional value. */
+#define MAXEXP2         ((1 <<EXPSIZE2) - 1)    /* Maximum exponent. */
+
+static comp2_t encode_comp2_t(u64 value)
+{
+	int exp, rnd;
+
+	exp = (value > (MAXFRACT2>>1));
+	rnd = 0;
+	while (value > MAXFRACT2) {
+		rnd = value & 1;
+		value >>= 1;
+		exp++;
+	}
+
+	/*
+	 * If we need to round up, do it (and handle overflow correctly).
+	 */
+	if (rnd && (++value > MAXFRACT2)) {
+		value >>= 1;
+		exp++;
+	}
+
+	if (exp > MAXEXP2) {
+		/* Overflow. Return largest representable number instead. */
+		return (1ul << (MANTSIZE2+EXPSIZE2-1)) - 1;
+	} else {
+		return (value & (MAXFRACT2>>1)) | (exp << (MANTSIZE2-1));
+	}
+}
+#endif
+
+#if ACCT_VERSION==3
+/*
+ * encode an u64 into a 32 bit IEEE float
+ */
+static u32 encode_float(u64 value)
+{
+	unsigned exp = 190;
+	unsigned u;
+
+	if (value==0) return 0;
+	while ((s64)value > 0){
+		value <<= 1;
+		exp--;
+	}
+	u = (u32)(value >> 40) & 0x7fffffu;
+	return u | (exp << 23);
+}
+#endif
+
+/*
+ *  Write an accounting entry for an exiting process
+ *
+ *  The acct_process() call is the workhorse of the process
+ *  accounting system. The struct acct is built here and then written
+ *  into the accounting file. This function should only be called from
+ *  do_exit() or when switching to a different output file.
+ */
+
+/*
+ *  do_acct_process does all actual work. Caller holds the reference to file.
+ */
+static void do_acct_process(struct bsd_acct_struct *acct,
+		struct pid_namespace *ns, struct file *file)
+{
+	struct pacct_struct *pacct = &current->signal->pacct;
+	acct_t ac;
+	mm_segment_t fs;
+	unsigned long flim;
+	u64 elapsed;
+	u64 run_time;
+	struct timespec uptime;
+	struct tty_struct *tty;
+	const struct cred *orig_cred;
+
+	/* Perform file operations on behalf of whoever enabled accounting */
+	orig_cred = override_creds(file->f_cred);
+
+	/*
+	 * First check to see if there is enough free_space to continue
+	 * the process accounting system.
+	 */
+	if (!check_free_space(acct, file))
+		goto out;
+
+	/*
+	 * Fill the accounting struct with the needed info as recorded
+	 * by the different kernel functions.
+	 */
+	memset(&ac, 0, sizeof(acct_t));
+
+	ac.ac_version = ACCT_VERSION | ACCT_BYTEORDER;
+	strlcpy(ac.ac_comm, current->comm, sizeof(ac.ac_comm));
+
+	/* calculate run_time in nsec*/
+	do_posix_clock_monotonic_gettime(&uptime);
+	run_time = (u64)uptime.tv_sec*NSEC_PER_SEC + uptime.tv_nsec;
+	run_time -= (u64)current->group_leader->start_time.tv_sec * NSEC_PER_SEC
+		       + current->group_leader->start_time.tv_nsec;
+	/* convert nsec -> AHZ */
+	elapsed = nsec_to_AHZ(run_time);
+#if ACCT_VERSION==3
+	ac.ac_etime = encode_float(elapsed);
+#else
+	ac.ac_etime = encode_comp_t(elapsed < (unsigned long) -1l ?
+	                       (unsigned long) elapsed : (unsigned long) -1l);
+#endif
+#if ACCT_VERSION==1 || ACCT_VERSION==2
+	{
+		/* new enlarged etime field */
+		comp2_t etime = encode_comp2_t(elapsed);
+		ac.ac_etime_hi = etime >> 16;
+		ac.ac_etime_lo = (u16) etime;
+	}
+#endif
+	do_div(elapsed, AHZ);
+	ac.ac_btime = get_seconds() - elapsed;
+	/* we really need to bite the bullet and change layout */
+	ac.ac_uid = orig_cred->uid;
+	ac.ac_gid = orig_cred->gid;
+#if ACCT_VERSION==2
+	ac.ac_ahz = AHZ;
+#endif
+#if ACCT_VERSION==1 || ACCT_VERSION==2
+	/* backward-compatible 16 bit fields */
+	ac.ac_uid16 = ac.ac_uid;
+	ac.ac_gid16 = ac.ac_gid;
+#endif
+#if ACCT_VERSION==3
+	ac.ac_pid = task_tgid_nr_ns(current, ns);
+	rcu_read_lock();
+	ac.ac_ppid = task_tgid_nr_ns(rcu_dereference(current->real_parent), ns);
+	rcu_read_unlock();
+#endif
+
+	spin_lock_irq(&current->sighand->siglock);
+	tty = current->signal->tty;	/* Safe as we hold the siglock */
+	ac.ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0;
+	ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
+	ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
+	ac.ac_flag = pacct->ac_flag;
+	ac.ac_mem = encode_comp_t(pacct->ac_mem);
+	ac.ac_minflt = encode_comp_t(pacct->ac_minflt);
+	ac.ac_majflt = encode_comp_t(pacct->ac_majflt);
+	ac.ac_exitcode = pacct->ac_exitcode;
+	spin_unlock_irq(&current->sighand->siglock);
+	ac.ac_io = encode_comp_t(0 /* current->io_usage */);	/* %% */
+	ac.ac_rw = encode_comp_t(ac.ac_io / 1024);
+	ac.ac_swaps = encode_comp_t(0);
+
+	/*
+	 * Kernel segment override to datasegment and write it
+	 * to the accounting file.
+	 */
+	fs = get_fs();
+	set_fs(KERNEL_DS);
+	/*
+	 * Accounting records are not subject to resource limits.
+	 */
+	flim = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+	current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
+	file->f_op->write(file, (char *)&ac,
+			       sizeof(acct_t), &file->f_pos);
+	current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim;
+	set_fs(fs);
+out:
+	revert_creds(orig_cred);
+}
+
+/**
+ * acct_collect - collect accounting information into pacct_struct
+ * @exitcode: task exit code
+ * @group_dead: not 0, if this thread is the last one in the process.
+ */
+void acct_collect(long exitcode, int group_dead)
+{
+	struct pacct_struct *pacct = &current->signal->pacct;
+	unsigned long vsize = 0;
+
+	if (group_dead && current->mm) {
+		struct vm_area_struct *vma;
+		down_read(&current->mm->mmap_sem);
+		vma = current->mm->mmap;
+		while (vma) {
+			vsize += vma->vm_end - vma->vm_start;
+			vma = vma->vm_next;
+		}
+		up_read(&current->mm->mmap_sem);
+	}
+
+	spin_lock_irq(&current->sighand->siglock);
+	if (group_dead)
+		pacct->ac_mem = vsize / 1024;
+	if (thread_group_leader(current)) {
+		pacct->ac_exitcode = exitcode;
+		if (current->flags & PF_FORKNOEXEC)
+			pacct->ac_flag |= AFORK;
+	}
+	if (current->flags & PF_SUPERPRIV)
+		pacct->ac_flag |= ASU;
+	if (current->flags & PF_DUMPCORE)
+		pacct->ac_flag |= ACORE;
+	if (current->flags & PF_SIGNALED)
+		pacct->ac_flag |= AXSIG;
+	pacct->ac_utime += current->utime;
+	pacct->ac_stime += current->stime;
+	pacct->ac_minflt += current->min_flt;
+	pacct->ac_majflt += current->maj_flt;
+	spin_unlock_irq(&current->sighand->siglock);
+}
+
+static void acct_process_in_ns(struct pid_namespace *ns)
+{
+	struct file *file = NULL;
+	struct bsd_acct_struct *acct;
+
+	acct = ns->bacct;
+	/*
+	 * accelerate the common fastpath:
+	 */
+	if (!acct || !acct->file)
+		return;
+
+	spin_lock(&acct_lock);
+	file = acct->file;
+	if (unlikely(!file)) {
+		spin_unlock(&acct_lock);
+		return;
+	}
+	get_file(file);
+	spin_unlock(&acct_lock);
+
+	do_acct_process(acct, ns, file);
+	fput(file);
+}
+
+/**
+ * acct_process - now just a wrapper around acct_process_in_ns,
+ * which in turn is a wrapper around do_acct_process.
+ *
+ * handles process accounting for an exiting task
+ */
+void acct_process(void)
+{
+	struct pid_namespace *ns;
+
+	/*
+	 * This loop is safe lockless, since current is still
+	 * alive and holds its namespace, which in turn holds
+	 * its parent.
+	 */
+	for (ns = task_active_pid_ns(current); ns != NULL; ns = ns->parent)
+		acct_process_in_ns(ns);
+}
diff --git a/kernel/async.c b/kernel/async.c
new file mode 100644
index 00000000000..bd0c168a3bb
--- /dev/null
+++ b/kernel/async.c
@@ -0,0 +1,301 @@
+/*
+ * async.c: Asynchronous function calls for boot performance
+ *
+ * (C) Copyright 2009 Intel Corporation
+ * Author: Arjan van de Ven <arjan@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+
+/*
+
+Goals and Theory of Operation
+
+The primary goal of this feature is to reduce the kernel boot time,
+by doing various independent hardware delays and discovery operations
+decoupled and not strictly serialized.
+
+More specifically, the asynchronous function call concept allows
+certain operations (primarily during system boot) to happen
+asynchronously, out of order, while these operations still
+have their externally visible parts happen sequentially and in-order.
+(not unlike how out-of-order CPUs retire their instructions in order)
+
+Key to the asynchronous function call implementation is the concept of
+a "sequence cookie" (which, although it has an abstracted type, can be
+thought of as a monotonically incrementing number).
+
+The async core will assign each scheduled event such a sequence cookie and
+pass this to the called functions.
+
+The asynchronously called function should before doing a globally visible
+operation, such as registering device numbers, call the
+async_synchronize_cookie() function and pass in its own cookie. The
+async_synchronize_cookie() function will make sure that all asynchronous
+operations that were scheduled prior to the operation corresponding with the
+cookie have completed.
+
+Subsystem/driver initialization code that scheduled asynchronous probe
+functions, but which shares global resources with other drivers/subsystems
+that do not use the asynchronous call feature, need to do a full
+synchronization with the async_synchronize_full() function, before returning
+from their init function. This is to maintain strict ordering between the
+asynchronous and synchronous parts of the kernel.
+
+*/
+
+#include <linux/async.h>
+#include <linux/atomic.h>
+#include <linux/ktime.h>
+#include <linux/export.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+static async_cookie_t next_cookie = 1;
+
+#define MAX_WORK	32768
+
+static LIST_HEAD(async_pending);
+static LIST_HEAD(async_running);
+static DEFINE_SPINLOCK(async_lock);
+
+struct async_entry {
+	struct list_head	list;
+	struct work_struct	work;
+	async_cookie_t		cookie;
+	async_func_ptr		*func;
+	void			*data;
+	struct list_head	*running;
+};
+
+static DECLARE_WAIT_QUEUE_HEAD(async_done);
+
+static atomic_t entry_count;
+
+
+/*
+ * MUST be called with the lock held!
+ */
+static async_cookie_t  __lowest_in_progress(struct list_head *running)
+{
+	struct async_entry *entry;
+
+	if (!list_empty(running)) {
+		entry = list_first_entry(running,
+			struct async_entry, list);
+		return entry->cookie;
+	}
+
+	list_for_each_entry(entry, &async_pending, list)
+		if (entry->running == running)
+			return entry->cookie;
+
+	return next_cookie;	/* "infinity" value */
+}
+
+static async_cookie_t  lowest_in_progress(struct list_head *running)
+{
+	unsigned long flags;
+	async_cookie_t ret;
+
+	spin_lock_irqsave(&async_lock, flags);
+	ret = __lowest_in_progress(running);
+	spin_unlock_irqrestore(&async_lock, flags);
+	return ret;
+}
+
+/*
+ * pick the first pending entry and run it
+ */
+static void async_run_entry_fn(struct work_struct *work)
+{
+	struct async_entry *entry =
+		container_of(work, struct async_entry, work);
+	unsigned long flags;
+	ktime_t uninitialized_var(calltime), delta, rettime;
+
+	/* 1) move self to the running queue */
+	spin_lock_irqsave(&async_lock, flags);
+	list_move_tail(&entry->list, entry->running);
+	spin_unlock_irqrestore(&async_lock, flags);
+
+	/* 2) run (and print duration) */
+	if (initcall_debug && system_state == SYSTEM_BOOTING) {
+		printk(KERN_DEBUG "calling  %lli_%pF @ %i\n",
+			(long long)entry->cookie,
+			entry->func, task_pid_nr(current));
+		calltime = ktime_get();
+	}
+	entry->func(entry->data, entry->cookie);
+	if (initcall_debug && system_state == SYSTEM_BOOTING) {
+		rettime = ktime_get();
+		delta = ktime_sub(rettime, calltime);
+		printk(KERN_DEBUG "initcall %lli_%pF returned 0 after %lld usecs\n",
+			(long long)entry->cookie,
+			entry->func,
+			(long long)ktime_to_ns(delta) >> 10);
+	}
+
+	/* 3) remove self from the running queue */
+	spin_lock_irqsave(&async_lock, flags);
+	list_del(&entry->list);
+
+	/* 4) free the entry */
+	kfree(entry);
+	atomic_dec(&entry_count);
+
+	spin_unlock_irqrestore(&async_lock, flags);
+
+	/* 5) wake up any waiters */
+	wake_up(&async_done);
+}
+
+static async_cookie_t __async_schedule(async_func_ptr *ptr, void *data, struct list_head *running)
+{
+	struct async_entry *entry;
+	unsigned long flags;
+	async_cookie_t newcookie;
+
+	/* allow irq-off callers */
+	entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
+
+	/*
+	 * If we're out of memory or if there's too much work
+	 * pending already, we execute synchronously.
+	 */
+	if (!entry || atomic_read(&entry_count) > MAX_WORK) {
+		kfree(entry);
+		spin_lock_irqsave(&async_lock, flags);
+		newcookie = next_cookie++;
+		spin_unlock_irqrestore(&async_lock, flags);
+
+		/* low on memory.. run synchronously */
+		ptr(data, newcookie);
+		return newcookie;
+	}
+	INIT_WORK(&entry->work, async_run_entry_fn);
+	entry->func = ptr;
+	entry->data = data;
+	entry->running = running;
+
+	spin_lock_irqsave(&async_lock, flags);
+	newcookie = entry->cookie = next_cookie++;
+	list_add_tail(&entry->list, &async_pending);
+	atomic_inc(&entry_count);
+	spin_unlock_irqrestore(&async_lock, flags);
+
+	/* schedule for execution */
+	queue_work(system_unbound_wq, &entry->work);
+
+	return newcookie;
+}
+
+/**
+ * async_schedule - schedule a function for asynchronous execution
+ * @ptr: function to execute asynchronously
+ * @data: data pointer to pass to the function
+ *
+ * Returns an async_cookie_t that may be used for checkpointing later.
+ * Note: This function may be called from atomic or non-atomic contexts.
+ */
+async_cookie_t async_schedule(async_func_ptr *ptr, void *data)
+{
+	return __async_schedule(ptr, data, &async_running);
+}
+EXPORT_SYMBOL_GPL(async_schedule);
+
+/**
+ * async_schedule_domain - schedule a function for asynchronous execution within a certain domain
+ * @ptr: function to execute asynchronously
+ * @data: data pointer to pass to the function
+ * @running: running list for the domain
+ *
+ * Returns an async_cookie_t that may be used for checkpointing later.
+ * @running may be used in the async_synchronize_*_domain() functions
+ * to wait within a certain synchronization domain rather than globally.
+ * A synchronization domain is specified via the running queue @running to use.
+ * Note: This function may be called from atomic or non-atomic contexts.
+ */
+async_cookie_t async_schedule_domain(async_func_ptr *ptr, void *data,
+				     struct list_head *running)
+{
+	return __async_schedule(ptr, data, running);
+}
+EXPORT_SYMBOL_GPL(async_schedule_domain);
+
+/**
+ * async_synchronize_full - synchronize all asynchronous function calls
+ *
+ * This function waits until all asynchronous function calls have been done.
+ */
+void async_synchronize_full(void)
+{
+	do {
+		async_synchronize_cookie(next_cookie);
+	} while (!list_empty(&async_running) || !list_empty(&async_pending));
+}
+EXPORT_SYMBOL_GPL(async_synchronize_full);
+
+/**
+ * async_synchronize_full_domain - synchronize all asynchronous function within a certain domain
+ * @list: running list to synchronize on
+ *
+ * This function waits until all asynchronous function calls for the
+ * synchronization domain specified by the running list @list have been done.
+ */
+void async_synchronize_full_domain(struct list_head *list)
+{
+	async_synchronize_cookie_domain(next_cookie, list);
+}
+EXPORT_SYMBOL_GPL(async_synchronize_full_domain);
+
+/**
+ * async_synchronize_cookie_domain - synchronize asynchronous function calls within a certain domain with cookie checkpointing
+ * @cookie: async_cookie_t to use as checkpoint
+ * @running: running list to synchronize on
+ *
+ * This function waits until all asynchronous function calls for the
+ * synchronization domain specified by the running list @list submitted
+ * prior to @cookie have been done.
+ */
+void async_synchronize_cookie_domain(async_cookie_t cookie,
+				     struct list_head *running)
+{
+	ktime_t uninitialized_var(starttime), delta, endtime;
+
+	if (initcall_debug && system_state == SYSTEM_BOOTING) {
+		printk(KERN_DEBUG "async_waiting @ %i\n", task_pid_nr(current));
+		starttime = ktime_get();
+	}
+
+	wait_event(async_done, lowest_in_progress(running) >= cookie);
+
+	if (initcall_debug && system_state == SYSTEM_BOOTING) {
+		endtime = ktime_get();
+		delta = ktime_sub(endtime, starttime);
+
+		printk(KERN_DEBUG "async_continuing @ %i after %lli usec\n",
+			task_pid_nr(current),
+			(long long)ktime_to_ns(delta) >> 10);
+	}
+}
+EXPORT_SYMBOL_GPL(async_synchronize_cookie_domain);
+
+/**
+ * async_synchronize_cookie - synchronize asynchronous function calls with cookie checkpointing
+ * @cookie: async_cookie_t to use as checkpoint
+ *
+ * This function waits until all asynchronous function calls prior to @cookie
+ * have been done.
+ */
+void async_synchronize_cookie(async_cookie_t cookie)
+{
+	async_synchronize_cookie_domain(cookie, &async_running);
+}
+EXPORT_SYMBOL_GPL(async_synchronize_cookie);
diff --git a/kernel/audit.c b/kernel/audit.c
new file mode 100644
index 00000000000..bb0eb5bb9a0
--- /dev/null
+++ b/kernel/audit.c
@@ -0,0 +1,1538 @@
+/* audit.c -- Auditing support
+ * Gateway between the kernel (e.g., selinux) and the user-space audit daemon.
+ * System-call specific features have moved to auditsc.c
+ *
+ * Copyright 2003-2007 Red Hat Inc., Durham, North Carolina.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Written by Rickard E. (Rik) Faith <faith@redhat.com>
+ *
+ * Goals: 1) Integrate fully with Security Modules.
+ *	  2) Minimal run-time overhead:
+ *	     a) Minimal when syscall auditing is disabled (audit_enable=0).
+ *	     b) Small when syscall auditing is enabled and no audit record
+ *		is generated (defer as much work as possible to record
+ *		generation time):
+ *		i) context is allocated,
+ *		ii) names from getname are stored without a copy, and
+ *		iii) inode information stored from path_lookup.
+ *	  3) Ability to disable syscall auditing at boot time (audit=0).
+ *	  4) Usable by other parts of the kernel (if audit_log* is called,
+ *	     then a syscall record will be generated automatically for the
+ *	     current syscall).
+ *	  5) Netlink interface to user-space.
+ *	  6) Support low-overhead kernel-based filtering to minimize the
+ *	     information that must be passed to user-space.
+ *
+ * Example user-space utilities: http://people.redhat.com/sgrubb/audit/
+ */
+
+#include <linux/init.h>
+#include <asm/types.h>
+#include <linux/atomic.h>
+#include <linux/mm.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/kthread.h>
+
+#include <linux/audit.h>
+
+#include <net/sock.h>
+#include <net/netlink.h>
+#include <linux/skbuff.h>
+#ifdef CONFIG_SECURITY
+#include <linux/security.h>
+#endif
+#include <linux/netlink.h>
+#include <linux/freezer.h>
+#include <linux/tty.h>
+
+#include "audit.h"
+
+/* No auditing will take place until audit_initialized == AUDIT_INITIALIZED.
+ * (Initialization happens after skb_init is called.) */
+#define AUDIT_DISABLED		-1
+#define AUDIT_UNINITIALIZED	0
+#define AUDIT_INITIALIZED	1
+static int	audit_initialized;
+
+#define AUDIT_OFF	0
+#define AUDIT_ON	1
+#define AUDIT_LOCKED	2
+int		audit_enabled;
+int		audit_ever_enabled;
+
+EXPORT_SYMBOL_GPL(audit_enabled);
+
+/* Default state when kernel boots without any parameters. */
+static int	audit_default;
+
+/* If auditing cannot proceed, audit_failure selects what happens. */
+static int	audit_failure = AUDIT_FAIL_PRINTK;
+
+/*
+ * If audit records are to be written to the netlink socket, audit_pid
+ * contains the pid of the auditd process and audit_nlk_pid contains
+ * the pid to use to send netlink messages to that process.
+ */
+int		audit_pid;
+static int	audit_nlk_pid;
+
+/* If audit_rate_limit is non-zero, limit the rate of sending audit records
+ * to that number per second.  This prevents DoS attacks, but results in
+ * audit records being dropped. */
+static int	audit_rate_limit;
+
+/* Number of outstanding audit_buffers allowed. */
+static int	audit_backlog_limit = 64;
+static int	audit_backlog_wait_time = 60 * HZ;
+static int	audit_backlog_wait_overflow = 0;
+
+/* The identity of the user shutting down the audit system. */
+uid_t		audit_sig_uid = -1;
+pid_t		audit_sig_pid = -1;
+u32		audit_sig_sid = 0;
+
+/* Records can be lost in several ways:
+   0) [suppressed in audit_alloc]
+   1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
+   2) out of memory in audit_log_move [alloc_skb]
+   3) suppressed due to audit_rate_limit
+   4) suppressed due to audit_backlog_limit
+*/
+static atomic_t    audit_lost = ATOMIC_INIT(0);
+
+/* The netlink socket. */
+static struct sock *audit_sock;
+
+/* Hash for inode-based rules */
+struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
+
+/* The audit_freelist is a list of pre-allocated audit buffers (if more
+ * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
+ * being placed on the freelist). */
+static DEFINE_SPINLOCK(audit_freelist_lock);
+static int	   audit_freelist_count;
+static LIST_HEAD(audit_freelist);
+
+static struct sk_buff_head audit_skb_queue;
+/* queue of skbs to send to auditd when/if it comes back */
+static struct sk_buff_head audit_skb_hold_queue;
+static struct task_struct *kauditd_task;
+static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
+static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
+
+/* Serialize requests from userspace. */
+DEFINE_MUTEX(audit_cmd_mutex);
+
+/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
+ * audit records.  Since printk uses a 1024 byte buffer, this buffer
+ * should be at least that large. */
+#define AUDIT_BUFSIZ 1024
+
+/* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
+ * audit_freelist.  Doing so eliminates many kmalloc/kfree calls. */
+#define AUDIT_MAXFREE  (2*NR_CPUS)
+
+/* The audit_buffer is used when formatting an audit record.  The caller
+ * locks briefly to get the record off the freelist or to allocate the
+ * buffer, and locks briefly to send the buffer to the netlink layer or
+ * to place it on a transmit queue.  Multiple audit_buffers can be in
+ * use simultaneously. */
+struct audit_buffer {
+	struct list_head     list;
+	struct sk_buff       *skb;	/* formatted skb ready to send */
+	struct audit_context *ctx;	/* NULL or associated context */
+	gfp_t		     gfp_mask;
+};
+
+struct audit_reply {
+	int pid;
+	struct sk_buff *skb;
+};
+
+static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
+{
+	if (ab) {
+		struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
+		nlh->nlmsg_pid = pid;
+	}
+}
+
+void audit_panic(const char *message)
+{
+	switch (audit_failure)
+	{
+	case AUDIT_FAIL_SILENT:
+		break;
+	case AUDIT_FAIL_PRINTK:
+		if (printk_ratelimit())
+			printk(KERN_ERR "audit: %s\n", message);
+		break;
+	case AUDIT_FAIL_PANIC:
+		/* test audit_pid since printk is always losey, why bother? */
+		if (audit_pid)
+			panic("audit: %s\n", message);
+		break;
+	}
+}
+
+static inline int audit_rate_check(void)
+{
+	static unsigned long	last_check = 0;
+	static int		messages   = 0;
+	static DEFINE_SPINLOCK(lock);
+	unsigned long		flags;
+	unsigned long		now;
+	unsigned long		elapsed;
+	int			retval	   = 0;
+
+	if (!audit_rate_limit) return 1;
+
+	spin_lock_irqsave(&lock, flags);
+	if (++messages < audit_rate_limit) {
+		retval = 1;
+	} else {
+		now     = jiffies;
+		elapsed = now - last_check;
+		if (elapsed > HZ) {
+			last_check = now;
+			messages   = 0;
+			retval     = 1;
+		}
+	}
+	spin_unlock_irqrestore(&lock, flags);
+
+	return retval;
+}
+
+/**
+ * audit_log_lost - conditionally log lost audit message event
+ * @message: the message stating reason for lost audit message
+ *
+ * Emit at least 1 message per second, even if audit_rate_check is
+ * throttling.
+ * Always increment the lost messages counter.
+*/
+void audit_log_lost(const char *message)
+{
+	static unsigned long	last_msg = 0;
+	static DEFINE_SPINLOCK(lock);
+	unsigned long		flags;
+	unsigned long		now;
+	int			print;
+
+	atomic_inc(&audit_lost);
+
+	print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
+
+	if (!print) {
+		spin_lock_irqsave(&lock, flags);
+		now = jiffies;
+		if (now - last_msg > HZ) {
+			print = 1;
+			last_msg = now;
+		}
+		spin_unlock_irqrestore(&lock, flags);
+	}
+
+	if (print) {
+		if (printk_ratelimit())
+			printk(KERN_WARNING
+				"audit: audit_lost=%d audit_rate_limit=%d "
+				"audit_backlog_limit=%d\n",
+				atomic_read(&audit_lost),
+				audit_rate_limit,
+				audit_backlog_limit);
+		audit_panic(message);
+	}
+}
+
+static int audit_log_config_change(char *function_name, int new, int old,
+				   uid_t loginuid, u32 sessionid, u32 sid,
+				   int allow_changes)
+{
+	struct audit_buffer *ab;
+	int rc = 0;
+
+	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+	audit_log_format(ab, "%s=%d old=%d auid=%u ses=%u", function_name, new,
+			 old, loginuid, sessionid);
+	if (sid) {
+		char *ctx = NULL;
+		u32 len;
+
+		rc = security_secid_to_secctx(sid, &ctx, &len);
+		if (rc) {
+			audit_log_format(ab, " sid=%u", sid);
+			allow_changes = 0; /* Something weird, deny request */
+		} else {
+			audit_log_format(ab, " subj=%s", ctx);
+			security_release_secctx(ctx, len);
+		}
+	}
+	audit_log_format(ab, " res=%d", allow_changes);
+	audit_log_end(ab);
+	return rc;
+}
+
+static int audit_do_config_change(char *function_name, int *to_change,
+				  int new, uid_t loginuid, u32 sessionid,
+				  u32 sid)
+{
+	int allow_changes, rc = 0, old = *to_change;
+
+	/* check if we are locked */
+	if (audit_enabled == AUDIT_LOCKED)
+		allow_changes = 0;
+	else
+		allow_changes = 1;
+
+	if (audit_enabled != AUDIT_OFF) {
+		rc = audit_log_config_change(function_name, new, old, loginuid,
+					     sessionid, sid, allow_changes);
+		if (rc)
+			allow_changes = 0;
+	}
+
+	/* If we are allowed, make the change */
+	if (allow_changes == 1)
+		*to_change = new;
+	/* Not allowed, update reason */
+	else if (rc == 0)
+		rc = -EPERM;
+	return rc;
+}
+
+static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sessionid,
+				u32 sid)
+{
+	return audit_do_config_change("audit_rate_limit", &audit_rate_limit,
+				      limit, loginuid, sessionid, sid);
+}
+
+static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sessionid,
+				   u32 sid)
+{
+	return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit,
+				      limit, loginuid, sessionid, sid);
+}
+
+static int audit_set_enabled(int state, uid_t loginuid, u32 sessionid, u32 sid)
+{
+	int rc;
+	if (state < AUDIT_OFF || state > AUDIT_LOCKED)
+		return -EINVAL;
+
+	rc =  audit_do_config_change("audit_enabled", &audit_enabled, state,
+				     loginuid, sessionid, sid);
+
+	if (!rc)
+		audit_ever_enabled |= !!state;
+
+	return rc;
+}
+
+static int audit_set_failure(int state, uid_t loginuid, u32 sessionid, u32 sid)
+{
+	if (state != AUDIT_FAIL_SILENT
+	    && state != AUDIT_FAIL_PRINTK
+	    && state != AUDIT_FAIL_PANIC)
+		return -EINVAL;
+
+	return audit_do_config_change("audit_failure", &audit_failure, state,
+				      loginuid, sessionid, sid);
+}
+
+/*
+ * Queue skbs to be sent to auditd when/if it comes back.  These skbs should
+ * already have been sent via prink/syslog and so if these messages are dropped
+ * it is not a huge concern since we already passed the audit_log_lost()
+ * notification and stuff.  This is just nice to get audit messages during
+ * boot before auditd is running or messages generated while auditd is stopped.
+ * This only holds messages is audit_default is set, aka booting with audit=1
+ * or building your kernel that way.
+ */
+static void audit_hold_skb(struct sk_buff *skb)
+{
+	if (audit_default &&
+	    skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)
+		skb_queue_tail(&audit_skb_hold_queue, skb);
+	else
+		kfree_skb(skb);
+}
+
+/*
+ * For one reason or another this nlh isn't getting delivered to the userspace
+ * audit daemon, just send it to printk.
+ */
+static void audit_printk_skb(struct sk_buff *skb)
+{
+	struct nlmsghdr *nlh = nlmsg_hdr(skb);
+	char *data = NLMSG_DATA(nlh);
+
+	if (nlh->nlmsg_type != AUDIT_EOE) {
+		if (printk_ratelimit())
+			printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data);
+		else
+			audit_log_lost("printk limit exceeded\n");
+	}
+
+	audit_hold_skb(skb);
+}
+
+static void kauditd_send_skb(struct sk_buff *skb)
+{
+	int err;
+	/* take a reference in case we can't send it and we want to hold it */
+	skb_get(skb);
+	err = netlink_unicast(audit_sock, skb, audit_nlk_pid, 0);
+	if (err < 0) {
+		BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
+		printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
+		audit_log_lost("auditd disappeared\n");
+		audit_pid = 0;
+		/* we might get lucky and get this in the next auditd */
+		audit_hold_skb(skb);
+	} else
+		/* drop the extra reference if sent ok */
+		consume_skb(skb);
+}
+
+static int kauditd_thread(void *dummy)
+{
+	struct sk_buff *skb;
+
+	set_freezable();
+	while (!kthread_should_stop()) {
+		/*
+		 * if auditd just started drain the queue of messages already
+		 * sent to syslog/printk.  remember loss here is ok.  we already
+		 * called audit_log_lost() if it didn't go out normally.  so the
+		 * race between the skb_dequeue and the next check for audit_pid
+		 * doesn't matter.
+		 *
+		 * if you ever find kauditd to be too slow we can get a perf win
+		 * by doing our own locking and keeping better track if there
+		 * are messages in this queue.  I don't see the need now, but
+		 * in 5 years when I want to play with this again I'll see this
+		 * note and still have no friggin idea what i'm thinking today.
+		 */
+		if (audit_default && audit_pid) {
+			skb = skb_dequeue(&audit_skb_hold_queue);
+			if (unlikely(skb)) {
+				while (skb && audit_pid) {
+					kauditd_send_skb(skb);
+					skb = skb_dequeue(&audit_skb_hold_queue);
+				}
+			}
+		}
+
+		skb = skb_dequeue(&audit_skb_queue);
+		wake_up(&audit_backlog_wait);
+		if (skb) {
+			if (audit_pid)
+				kauditd_send_skb(skb);
+			else
+				audit_printk_skb(skb);
+		} else {
+			DECLARE_WAITQUEUE(wait, current);
+			set_current_state(TASK_INTERRUPTIBLE);
+			add_wait_queue(&kauditd_wait, &wait);
+
+			if (!skb_queue_len(&audit_skb_queue)) {
+				try_to_freeze();
+				schedule();
+			}
+
+			__set_current_state(TASK_RUNNING);
+			remove_wait_queue(&kauditd_wait, &wait);
+		}
+	}
+	return 0;
+}
+
+static int audit_prepare_user_tty(pid_t pid, uid_t loginuid, u32 sessionid)
+{
+	struct task_struct *tsk;
+	int err;
+
+	rcu_read_lock();
+	tsk = find_task_by_vpid(pid);
+	if (!tsk) {
+		rcu_read_unlock();
+		return -ESRCH;
+	}
+	get_task_struct(tsk);
+	rcu_read_unlock();
+	err = tty_audit_push_task(tsk, loginuid, sessionid);
+	put_task_struct(tsk);
+	return err;
+}
+
+int audit_send_list(void *_dest)
+{
+	struct audit_netlink_list *dest = _dest;
+	int pid = dest->pid;
+	struct sk_buff *skb;
+
+	/* wait for parent to finish and send an ACK */
+	mutex_lock(&audit_cmd_mutex);
+	mutex_unlock(&audit_cmd_mutex);
+
+	while ((skb = __skb_dequeue(&dest->q)) != NULL)
+		netlink_unicast(audit_sock, skb, pid, 0);
+
+	kfree(dest);
+
+	return 0;
+}
+
+struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
+				 int multi, const void *payload, int size)
+{
+	struct sk_buff	*skb;
+	struct nlmsghdr	*nlh;
+	void		*data;
+	int		flags = multi ? NLM_F_MULTI : 0;
+	int		t     = done  ? NLMSG_DONE  : type;
+
+	skb = nlmsg_new(size, GFP_KERNEL);
+	if (!skb)
+		return NULL;
+
+	nlh	= NLMSG_NEW(skb, pid, seq, t, size, flags);
+	data	= NLMSG_DATA(nlh);
+	memcpy(data, payload, size);
+	return skb;
+
+nlmsg_failure:			/* Used by NLMSG_NEW */
+	if (skb)
+		kfree_skb(skb);
+	return NULL;
+}
+
+static int audit_send_reply_thread(void *arg)
+{
+	struct audit_reply *reply = (struct audit_reply *)arg;
+
+	mutex_lock(&audit_cmd_mutex);
+	mutex_unlock(&audit_cmd_mutex);
+
+	/* Ignore failure. It'll only happen if the sender goes away,
+	   because our timeout is set to infinite. */
+	netlink_unicast(audit_sock, reply->skb, reply->pid, 0);
+	kfree(reply);
+	return 0;
+}
+/**
+ * audit_send_reply - send an audit reply message via netlink
+ * @pid: process id to send reply to
+ * @seq: sequence number
+ * @type: audit message type
+ * @done: done (last) flag
+ * @multi: multi-part message flag
+ * @payload: payload data
+ * @size: payload size
+ *
+ * Allocates an skb, builds the netlink message, and sends it to the pid.
+ * No failure notifications.
+ */
+static void audit_send_reply(int pid, int seq, int type, int done, int multi,
+			     const void *payload, int size)
+{
+	struct sk_buff *skb;
+	struct task_struct *tsk;
+	struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
+					    GFP_KERNEL);
+
+	if (!reply)
+		return;
+
+	skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
+	if (!skb)
+		goto out;
+
+	reply->pid = pid;
+	reply->skb = skb;
+
+	tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
+	if (!IS_ERR(tsk))
+		return;
+	kfree_skb(skb);
+out:
+	kfree(reply);
+}
+
+/*
+ * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
+ * control messages.
+ */
+static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
+{
+	int err = 0;
+
+	switch (msg_type) {
+	case AUDIT_GET:
+	case AUDIT_LIST:
+	case AUDIT_LIST_RULES:
+	case AUDIT_SET:
+	case AUDIT_ADD:
+	case AUDIT_ADD_RULE:
+	case AUDIT_DEL:
+	case AUDIT_DEL_RULE:
+	case AUDIT_SIGNAL_INFO:
+	case AUDIT_TTY_GET:
+	case AUDIT_TTY_SET:
+	case AUDIT_TRIM:
+	case AUDIT_MAKE_EQUIV:
+		if (!capable(CAP_AUDIT_CONTROL))
+			err = -EPERM;
+		break;
+	case AUDIT_USER:
+	case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
+	case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
+		if (!capable(CAP_AUDIT_WRITE))
+			err = -EPERM;
+		break;
+	default:  /* bad msg */
+		err = -EINVAL;
+	}
+
+	return err;
+}
+
+static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
+				     u32 pid, u32 uid, uid_t auid, u32 ses,
+				     u32 sid)
+{
+	int rc = 0;
+	char *ctx = NULL;
+	u32 len;
+
+	if (!audit_enabled) {
+		*ab = NULL;
+		return rc;
+	}
+
+	*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
+	audit_log_format(*ab, "pid=%d uid=%u auid=%u ses=%u",
+			 pid, uid, auid, ses);
+	if (sid) {
+		rc = security_secid_to_secctx(sid, &ctx, &len);
+		if (rc)
+			audit_log_format(*ab, " ssid=%u", sid);
+		else {
+			audit_log_format(*ab, " subj=%s", ctx);
+			security_release_secctx(ctx, len);
+		}
+	}
+
+	return rc;
+}
+
+static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+	u32			uid, pid, seq, sid;
+	void			*data;
+	struct audit_status	*status_get, status_set;
+	int			err;
+	struct audit_buffer	*ab;
+	u16			msg_type = nlh->nlmsg_type;
+	uid_t			loginuid; /* loginuid of sender */
+	u32			sessionid;
+	struct audit_sig_info   *sig_data;
+	char			*ctx = NULL;
+	u32			len;
+
+	err = audit_netlink_ok(skb, msg_type);
+	if (err)
+		return err;
+
+	/* As soon as there's any sign of userspace auditd,
+	 * start kauditd to talk to it */
+	if (!kauditd_task)
+		kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
+	if (IS_ERR(kauditd_task)) {
+		err = PTR_ERR(kauditd_task);
+		kauditd_task = NULL;
+		return err;
+	}
+
+	pid  = NETLINK_CREDS(skb)->pid;
+	uid  = NETLINK_CREDS(skb)->uid;
+	loginuid = audit_get_loginuid(current);
+	sessionid = audit_get_sessionid(current);
+	security_task_getsecid(current, &sid);
+	seq  = nlh->nlmsg_seq;
+	data = NLMSG_DATA(nlh);
+
+	switch (msg_type) {
+	case AUDIT_GET:
+		status_set.enabled	 = audit_enabled;
+		status_set.failure	 = audit_failure;
+		status_set.pid		 = audit_pid;
+		status_set.rate_limit	 = audit_rate_limit;
+		status_set.backlog_limit = audit_backlog_limit;
+		status_set.lost		 = atomic_read(&audit_lost);
+		status_set.backlog	 = skb_queue_len(&audit_skb_queue);
+		audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_GET, 0, 0,
+				 &status_set, sizeof(status_set));
+		break;
+	case AUDIT_SET:
+		if (nlh->nlmsg_len < sizeof(struct audit_status))
+			return -EINVAL;
+		status_get   = (struct audit_status *)data;
+		if (status_get->mask & AUDIT_STATUS_ENABLED) {
+			err = audit_set_enabled(status_get->enabled,
+						loginuid, sessionid, sid);
+			if (err < 0)
+				return err;
+		}
+		if (status_get->mask & AUDIT_STATUS_FAILURE) {
+			err = audit_set_failure(status_get->failure,
+						loginuid, sessionid, sid);
+			if (err < 0)
+				return err;
+		}
+		if (status_get->mask & AUDIT_STATUS_PID) {
+			int new_pid = status_get->pid;
+
+			if (audit_enabled != AUDIT_OFF)
+				audit_log_config_change("audit_pid", new_pid,
+							audit_pid, loginuid,
+							sessionid, sid, 1);
+
+			audit_pid = new_pid;
+			audit_nlk_pid = NETLINK_CB(skb).pid;
+		}
+		if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) {
+			err = audit_set_rate_limit(status_get->rate_limit,
+						   loginuid, sessionid, sid);
+			if (err < 0)
+				return err;
+		}
+		if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
+			err = audit_set_backlog_limit(status_get->backlog_limit,
+						      loginuid, sessionid, sid);
+		break;
+	case AUDIT_USER:
+	case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
+	case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
+		if (!audit_enabled && msg_type != AUDIT_USER_AVC)
+			return 0;
+
+		err = audit_filter_user(&NETLINK_CB(skb));
+		if (err == 1) {
+			err = 0;
+			if (msg_type == AUDIT_USER_TTY) {
+				err = audit_prepare_user_tty(pid, loginuid,
+							     sessionid);
+				if (err)
+					break;
+			}
+			audit_log_common_recv_msg(&ab, msg_type, pid, uid,
+						  loginuid, sessionid, sid);
+
+			if (msg_type != AUDIT_USER_TTY)
+				audit_log_format(ab, " msg='%.1024s'",
+						 (char *)data);
+			else {
+				int size;
+
+				audit_log_format(ab, " msg=");
+				size = nlmsg_len(nlh);
+				if (size > 0 &&
+				    ((unsigned char *)data)[size - 1] == '\0')
+					size--;
+				audit_log_n_untrustedstring(ab, data, size);
+			}
+			audit_set_pid(ab, pid);
+			audit_log_end(ab);
+		}
+		break;
+	case AUDIT_ADD:
+	case AUDIT_DEL:
+		if (nlmsg_len(nlh) < sizeof(struct audit_rule))
+			return -EINVAL;
+		if (audit_enabled == AUDIT_LOCKED) {
+			audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+						  uid, loginuid, sessionid, sid);
+
+			audit_log_format(ab, " audit_enabled=%d res=0",
+					 audit_enabled);
+			audit_log_end(ab);
+			return -EPERM;
+		}
+		/* fallthrough */
+	case AUDIT_LIST:
+		err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
+					   uid, seq, data, nlmsg_len(nlh),
+					   loginuid, sessionid, sid);
+		break;
+	case AUDIT_ADD_RULE:
+	case AUDIT_DEL_RULE:
+		if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
+			return -EINVAL;
+		if (audit_enabled == AUDIT_LOCKED) {
+			audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+						  uid, loginuid, sessionid, sid);
+
+			audit_log_format(ab, " audit_enabled=%d res=0",
+					 audit_enabled);
+			audit_log_end(ab);
+			return -EPERM;
+		}
+		/* fallthrough */
+	case AUDIT_LIST_RULES:
+		err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
+					   uid, seq, data, nlmsg_len(nlh),
+					   loginuid, sessionid, sid);
+		break;
+	case AUDIT_TRIM:
+		audit_trim_trees();
+
+		audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+					  uid, loginuid, sessionid, sid);
+
+		audit_log_format(ab, " op=trim res=1");
+		audit_log_end(ab);
+		break;
+	case AUDIT_MAKE_EQUIV: {
+		void *bufp = data;
+		u32 sizes[2];
+		size_t msglen = nlmsg_len(nlh);
+		char *old, *new;
+
+		err = -EINVAL;
+		if (msglen < 2 * sizeof(u32))
+			break;
+		memcpy(sizes, bufp, 2 * sizeof(u32));
+		bufp += 2 * sizeof(u32);
+		msglen -= 2 * sizeof(u32);
+		old = audit_unpack_string(&bufp, &msglen, sizes[0]);
+		if (IS_ERR(old)) {
+			err = PTR_ERR(old);
+			break;
+		}
+		new = audit_unpack_string(&bufp, &msglen, sizes[1]);
+		if (IS_ERR(new)) {
+			err = PTR_ERR(new);
+			kfree(old);
+			break;
+		}
+		/* OK, here comes... */
+		err = audit_tag_tree(old, new);
+
+		audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+					  uid, loginuid, sessionid, sid);
+
+		audit_log_format(ab, " op=make_equiv old=");
+		audit_log_untrustedstring(ab, old);
+		audit_log_format(ab, " new=");
+		audit_log_untrustedstring(ab, new);
+		audit_log_format(ab, " res=%d", !err);
+		audit_log_end(ab);
+		kfree(old);
+		kfree(new);
+		break;
+	}
+	case AUDIT_SIGNAL_INFO:
+		len = 0;
+		if (audit_sig_sid) {
+			err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
+			if (err)
+				return err;
+		}
+		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
+		if (!sig_data) {
+			if (audit_sig_sid)
+				security_release_secctx(ctx, len);
+			return -ENOMEM;
+		}
+		sig_data->uid = audit_sig_uid;
+		sig_data->pid = audit_sig_pid;
+		if (audit_sig_sid) {
+			memcpy(sig_data->ctx, ctx, len);
+			security_release_secctx(ctx, len);
+		}
+		audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
+				0, 0, sig_data, sizeof(*sig_data) + len);
+		kfree(sig_data);
+		break;
+	case AUDIT_TTY_GET: {
+		struct audit_tty_status s;
+		struct task_struct *tsk;
+		unsigned long flags;
+
+		rcu_read_lock();
+		tsk = find_task_by_vpid(pid);
+		if (tsk && lock_task_sighand(tsk, &flags)) {
+			s.enabled = tsk->signal->audit_tty != 0;
+			unlock_task_sighand(tsk, &flags);
+		} else
+			err = -ESRCH;
+		rcu_read_unlock();
+
+		if (!err)
+			audit_send_reply(NETLINK_CB(skb).pid, seq,
+					 AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
+		break;
+	}
+	case AUDIT_TTY_SET: {
+		struct audit_tty_status *s;
+		struct task_struct *tsk;
+		unsigned long flags;
+
+		if (nlh->nlmsg_len < sizeof(struct audit_tty_status))
+			return -EINVAL;
+		s = data;
+		if (s->enabled != 0 && s->enabled != 1)
+			return -EINVAL;
+		rcu_read_lock();
+		tsk = find_task_by_vpid(pid);
+		if (tsk && lock_task_sighand(tsk, &flags)) {
+			tsk->signal->audit_tty = s->enabled != 0;
+			unlock_task_sighand(tsk, &flags);
+		} else
+			err = -ESRCH;
+		rcu_read_unlock();
+		break;
+	}
+	default:
+		err = -EINVAL;
+		break;
+	}
+
+	return err < 0 ? err : 0;
+}
+
+/*
+ * Get message from skb.  Each message is processed by audit_receive_msg.
+ * Malformed skbs with wrong length are discarded silently.
+ */
+static void audit_receive_skb(struct sk_buff *skb)
+{
+	struct nlmsghdr *nlh;
+	/*
+	 * len MUST be signed for NLMSG_NEXT to be able to dec it below 0
+	 * if the nlmsg_len was not aligned
+	 */
+	int len;
+	int err;
+
+	nlh = nlmsg_hdr(skb);
+	len = skb->len;
+
+	while (NLMSG_OK(nlh, len)) {
+		err = audit_receive_msg(skb, nlh);
+		/* if err or if this message says it wants a response */
+		if (err || (nlh->nlmsg_flags & NLM_F_ACK))
+			netlink_ack(skb, nlh, err);
+
+		nlh = NLMSG_NEXT(nlh, len);
+	}
+}
+
+/* Receive messages from netlink socket. */
+static void audit_receive(struct sk_buff  *skb)
+{
+	mutex_lock(&audit_cmd_mutex);
+	audit_receive_skb(skb);
+	mutex_unlock(&audit_cmd_mutex);
+}
+
+/* Initialize audit support at boot time. */
+static int __init audit_init(void)
+{
+	int i;
+
+	if (audit_initialized == AUDIT_DISABLED)
+		return 0;
+
+	printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
+	       audit_default ? "enabled" : "disabled");
+	audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, 0,
+					   audit_receive, NULL, THIS_MODULE);
+	if (!audit_sock)
+		audit_panic("cannot initialize netlink socket");
+	else
+		audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
+
+	skb_queue_head_init(&audit_skb_queue);
+	skb_queue_head_init(&audit_skb_hold_queue);
+	audit_initialized = AUDIT_INITIALIZED;
+	audit_enabled = audit_default;
+	audit_ever_enabled |= !!audit_default;
+
+	audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
+
+	for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
+		INIT_LIST_HEAD(&audit_inode_hash[i]);
+
+	return 0;
+}
+__initcall(audit_init);
+
+/* Process kernel command-line parameter at boot time.  audit=0 or audit=1. */
+static int __init audit_enable(char *str)
+{
+	audit_default = !!simple_strtol(str, NULL, 0);
+	if (!audit_default)
+		audit_initialized = AUDIT_DISABLED;
+
+	printk(KERN_INFO "audit: %s", audit_default ? "enabled" : "disabled");
+
+	if (audit_initialized == AUDIT_INITIALIZED) {
+		audit_enabled = audit_default;
+		audit_ever_enabled |= !!audit_default;
+	} else if (audit_initialized == AUDIT_UNINITIALIZED) {
+		printk(" (after initialization)");
+	} else {
+		printk(" (until reboot)");
+	}
+	printk("\n");
+
+	return 1;
+}
+
+__setup("audit=", audit_enable);
+
+static void audit_buffer_free(struct audit_buffer *ab)
+{
+	unsigned long flags;
+
+	if (!ab)
+		return;
+
+	if (ab->skb)
+		kfree_skb(ab->skb);
+
+	spin_lock_irqsave(&audit_freelist_lock, flags);
+	if (audit_freelist_count > AUDIT_MAXFREE)
+		kfree(ab);
+	else {
+		audit_freelist_count++;
+		list_add(&ab->list, &audit_freelist);
+	}
+	spin_unlock_irqrestore(&audit_freelist_lock, flags);
+}
+
+static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
+						gfp_t gfp_mask, int type)
+{
+	unsigned long flags;
+	struct audit_buffer *ab = NULL;
+	struct nlmsghdr *nlh;
+
+	spin_lock_irqsave(&audit_freelist_lock, flags);
+	if (!list_empty(&audit_freelist)) {
+		ab = list_entry(audit_freelist.next,
+				struct audit_buffer, list);
+		list_del(&ab->list);
+		--audit_freelist_count;
+	}
+	spin_unlock_irqrestore(&audit_freelist_lock, flags);
+
+	if (!ab) {
+		ab = kmalloc(sizeof(*ab), gfp_mask);
+		if (!ab)
+			goto err;
+	}
+
+	ab->ctx = ctx;
+	ab->gfp_mask = gfp_mask;
+
+	ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask);
+	if (!ab->skb)
+		goto nlmsg_failure;
+
+	nlh = NLMSG_NEW(ab->skb, 0, 0, type, 0, 0);
+
+	return ab;
+
+nlmsg_failure:                  /* Used by NLMSG_NEW */
+	kfree_skb(ab->skb);
+	ab->skb = NULL;
+err:
+	audit_buffer_free(ab);
+	return NULL;
+}
+
+/**
+ * audit_serial - compute a serial number for the audit record
+ *
+ * Compute a serial number for the audit record.  Audit records are
+ * written to user-space as soon as they are generated, so a complete
+ * audit record may be written in several pieces.  The timestamp of the
+ * record and this serial number are used by the user-space tools to
+ * determine which pieces belong to the same audit record.  The
+ * (timestamp,serial) tuple is unique for each syscall and is live from
+ * syscall entry to syscall exit.
+ *
+ * NOTE: Another possibility is to store the formatted records off the
+ * audit context (for those records that have a context), and emit them
+ * all at syscall exit.  However, this could delay the reporting of
+ * significant errors until syscall exit (or never, if the system
+ * halts).
+ */
+unsigned int audit_serial(void)
+{
+	static DEFINE_SPINLOCK(serial_lock);
+	static unsigned int serial = 0;
+
+	unsigned long flags;
+	unsigned int ret;
+
+	spin_lock_irqsave(&serial_lock, flags);
+	do {
+		ret = ++serial;
+	} while (unlikely(!ret));
+	spin_unlock_irqrestore(&serial_lock, flags);
+
+	return ret;
+}
+
+static inline void audit_get_stamp(struct audit_context *ctx,
+				   struct timespec *t, unsigned int *serial)
+{
+	if (!ctx || !auditsc_get_stamp(ctx, t, serial)) {
+		*t = CURRENT_TIME;
+		*serial = audit_serial();
+	}
+}
+
+/* Obtain an audit buffer.  This routine does locking to obtain the
+ * audit buffer, but then no locking is required for calls to
+ * audit_log_*format.  If the tsk is a task that is currently in a
+ * syscall, then the syscall is marked as auditable and an audit record
+ * will be written at syscall exit.  If there is no associated task, tsk
+ * should be NULL. */
+
+/**
+ * audit_log_start - obtain an audit buffer
+ * @ctx: audit_context (may be NULL)
+ * @gfp_mask: type of allocation
+ * @type: audit message type
+ *
+ * Returns audit_buffer pointer on success or NULL on error.
+ *
+ * Obtain an audit buffer.  This routine does locking to obtain the
+ * audit buffer, but then no locking is required for calls to
+ * audit_log_*format.  If the task (ctx) is a task that is currently in a
+ * syscall, then the syscall is marked as auditable and an audit record
+ * will be written at syscall exit.  If there is no associated task, then
+ * task context (ctx) should be NULL.
+ */
+struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
+				     int type)
+{
+	struct audit_buffer	*ab	= NULL;
+	struct timespec		t;
+	unsigned int		uninitialized_var(serial);
+	int reserve;
+	unsigned long timeout_start = jiffies;
+
+	if (audit_initialized != AUDIT_INITIALIZED)
+		return NULL;
+
+	if (unlikely(audit_filter_type(type)))
+		return NULL;
+
+	if (gfp_mask & __GFP_WAIT)
+		reserve = 0;
+	else
+		reserve = 5; /* Allow atomic callers to go up to five
+				entries over the normal backlog limit */
+
+	while (audit_backlog_limit
+	       && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
+		if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time
+		    && time_before(jiffies, timeout_start + audit_backlog_wait_time)) {
+
+			/* Wait for auditd to drain the queue a little */
+			DECLARE_WAITQUEUE(wait, current);
+			set_current_state(TASK_INTERRUPTIBLE);
+			add_wait_queue(&audit_backlog_wait, &wait);
+
+			if (audit_backlog_limit &&
+			    skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
+				schedule_timeout(timeout_start + audit_backlog_wait_time - jiffies);
+
+			__set_current_state(TASK_RUNNING);
+			remove_wait_queue(&audit_backlog_wait, &wait);
+			continue;
+		}
+		if (audit_rate_check() && printk_ratelimit())
+			printk(KERN_WARNING
+			       "audit: audit_backlog=%d > "
+			       "audit_backlog_limit=%d\n",
+			       skb_queue_len(&audit_skb_queue),
+			       audit_backlog_limit);
+		audit_log_lost("backlog limit exceeded");
+		audit_backlog_wait_time = audit_backlog_wait_overflow;
+		wake_up(&audit_backlog_wait);
+		return NULL;
+	}
+
+	ab = audit_buffer_alloc(ctx, gfp_mask, type);
+	if (!ab) {
+		audit_log_lost("out of memory in audit_log_start");
+		return NULL;
+	}
+
+	audit_get_stamp(ab->ctx, &t, &serial);
+
+	audit_log_format(ab, "audit(%lu.%03lu:%u): ",
+			 t.tv_sec, t.tv_nsec/1000000, serial);
+	return ab;
+}
+
+/**
+ * audit_expand - expand skb in the audit buffer
+ * @ab: audit_buffer
+ * @extra: space to add at tail of the skb
+ *
+ * Returns 0 (no space) on failed expansion, or available space if
+ * successful.
+ */
+static inline int audit_expand(struct audit_buffer *ab, int extra)
+{
+	struct sk_buff *skb = ab->skb;
+	int oldtail = skb_tailroom(skb);
+	int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask);
+	int newtail = skb_tailroom(skb);
+
+	if (ret < 0) {
+		audit_log_lost("out of memory in audit_expand");
+		return 0;
+	}
+
+	skb->truesize += newtail - oldtail;
+	return newtail;
+}
+
+/*
+ * Format an audit message into the audit buffer.  If there isn't enough
+ * room in the audit buffer, more room will be allocated and vsnprint
+ * will be called a second time.  Currently, we assume that a printk
+ * can't format message larger than 1024 bytes, so we don't either.
+ */
+static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
+			      va_list args)
+{
+	int len, avail;
+	struct sk_buff *skb;
+	va_list args2;
+
+	if (!ab)
+		return;
+
+	BUG_ON(!ab->skb);
+	skb = ab->skb;
+	avail = skb_tailroom(skb);
+	if (avail == 0) {
+		avail = audit_expand(ab, AUDIT_BUFSIZ);
+		if (!avail)
+			goto out;
+	}
+	va_copy(args2, args);
+	len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
+	if (len >= avail) {
+		/* The printk buffer is 1024 bytes long, so if we get
+		 * here and AUDIT_BUFSIZ is at least 1024, then we can
+		 * log everything that printk could have logged. */
+		avail = audit_expand(ab,
+			max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
+		if (!avail)
+			goto out_va_end;
+		len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
+	}
+	if (len > 0)
+		skb_put(skb, len);
+out_va_end:
+	va_end(args2);
+out:
+	return;
+}
+
+/**
+ * audit_log_format - format a message into the audit buffer.
+ * @ab: audit_buffer
+ * @fmt: format string
+ * @...: optional parameters matching @fmt string
+ *
+ * All the work is done in audit_log_vformat.
+ */
+void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
+{
+	va_list args;
+
+	if (!ab)
+		return;
+	va_start(args, fmt);
+	audit_log_vformat(ab, fmt, args);
+	va_end(args);
+}
+
+/**
+ * audit_log_hex - convert a buffer to hex and append it to the audit skb
+ * @ab: the audit_buffer
+ * @buf: buffer to convert to hex
+ * @len: length of @buf to be converted
+ *
+ * No return value; failure to expand is silently ignored.
+ *
+ * This function will take the passed buf and convert it into a string of
+ * ascii hex digits. The new string is placed onto the skb.
+ */
+void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
+		size_t len)
+{
+	int i, avail, new_len;
+	unsigned char *ptr;
+	struct sk_buff *skb;
+	static const unsigned char *hex = "0123456789ABCDEF";
+
+	if (!ab)
+		return;
+
+	BUG_ON(!ab->skb);
+	skb = ab->skb;
+	avail = skb_tailroom(skb);
+	new_len = len<<1;
+	if (new_len >= avail) {
+		/* Round the buffer request up to the next multiple */
+		new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
+		avail = audit_expand(ab, new_len);
+		if (!avail)
+			return;
+	}
+
+	ptr = skb_tail_pointer(skb);
+	for (i=0; i<len; i++) {
+		*ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */
+		*ptr++ = hex[buf[i] & 0x0F];	  /* Lower nibble */
+	}
+	*ptr = 0;
+	skb_put(skb, len << 1); /* new string is twice the old string */
+}
+
+/*
+ * Format a string of no more than slen characters into the audit buffer,
+ * enclosed in quote marks.
+ */
+void audit_log_n_string(struct audit_buffer *ab, const char *string,
+			size_t slen)
+{
+	int avail, new_len;
+	unsigned char *ptr;
+	struct sk_buff *skb;
+
+	if (!ab)
+		return;
+
+	BUG_ON(!ab->skb);
+	skb = ab->skb;
+	avail = skb_tailroom(skb);
+	new_len = slen + 3;	/* enclosing quotes + null terminator */
+	if (new_len > avail) {
+		avail = audit_expand(ab, new_len);
+		if (!avail)
+			return;
+	}
+	ptr = skb_tail_pointer(skb);
+	*ptr++ = '"';
+	memcpy(ptr, string, slen);
+	ptr += slen;
+	*ptr++ = '"';
+	*ptr = 0;
+	skb_put(skb, slen + 2);	/* don't include null terminator */
+}
+
+/**
+ * audit_string_contains_control - does a string need to be logged in hex
+ * @string: string to be checked
+ * @len: max length of the string to check
+ */
+int audit_string_contains_control(const char *string, size_t len)
+{
+	const unsigned char *p;
+	for (p = string; p < (const unsigned char *)string + len; p++) {
+		if (*p == '"' || *p < 0x21 || *p > 0x7e)
+			return 1;
+	}
+	return 0;
+}
+
+/**
+ * audit_log_n_untrustedstring - log a string that may contain random characters
+ * @ab: audit_buffer
+ * @len: length of string (not including trailing null)
+ * @string: string to be logged
+ *
+ * This code will escape a string that is passed to it if the string
+ * contains a control character, unprintable character, double quote mark,
+ * or a space. Unescaped strings will start and end with a double quote mark.
+ * Strings that are escaped are printed in hex (2 digits per char).
+ *
+ * The caller specifies the number of characters in the string to log, which may
+ * or may not be the entire string.
+ */
+void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
+				 size_t len)
+{
+	if (audit_string_contains_control(string, len))
+		audit_log_n_hex(ab, string, len);
+	else
+		audit_log_n_string(ab, string, len);
+}
+
+/**
+ * audit_log_untrustedstring - log a string that may contain random characters
+ * @ab: audit_buffer
+ * @string: string to be logged
+ *
+ * Same as audit_log_n_untrustedstring(), except that strlen is used to
+ * determine string length.
+ */
+void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
+{
+	audit_log_n_untrustedstring(ab, string, strlen(string));
+}
+
+/* This is a helper-function to print the escaped d_path */
+void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
+		      struct path *path)
+{
+	char *p, *pathname;
+
+	if (prefix)
+		audit_log_format(ab, "%s", prefix);
+
+	/* We will allow 11 spaces for ' (deleted)' to be appended */
+	pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
+	if (!pathname) {
+		audit_log_string(ab, "<no_memory>");
+		return;
+	}
+	p = d_path(path, pathname, PATH_MAX+11);
+	if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
+		/* FIXME: can we save some information here? */
+		audit_log_string(ab, "<too_long>");
+	} else
+		audit_log_untrustedstring(ab, p);
+	kfree(pathname);
+}
+
+void audit_log_key(struct audit_buffer *ab, char *key)
+{
+	audit_log_format(ab, " key=");
+	if (key)
+		audit_log_untrustedstring(ab, key);
+	else
+		audit_log_format(ab, "(null)");
+}
+
+/**
+ * audit_log_end - end one audit record
+ * @ab: the audit_buffer
+ *
+ * The netlink_* functions cannot be called inside an irq context, so
+ * the audit buffer is placed on a queue and a tasklet is scheduled to
+ * remove them from the queue outside the irq context.  May be called in
+ * any context.
+ */
+void audit_log_end(struct audit_buffer *ab)
+{
+	if (!ab)
+		return;
+	if (!audit_rate_check()) {
+		audit_log_lost("rate limit exceeded");
+	} else {
+		struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
+		nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
+
+		if (audit_pid) {
+			skb_queue_tail(&audit_skb_queue, ab->skb);
+			wake_up_interruptible(&kauditd_wait);
+		} else {
+			audit_printk_skb(ab->skb);
+		}
+		ab->skb = NULL;
+	}
+	audit_buffer_free(ab);
+}
+
+/**
+ * audit_log - Log an audit record
+ * @ctx: audit context
+ * @gfp_mask: type of allocation
+ * @type: audit message type
+ * @fmt: format string to use
+ * @...: variable parameters matching the format string
+ *
+ * This is a convenience function that calls audit_log_start,
+ * audit_log_vformat, and audit_log_end.  It may be called
+ * in any context.
+ */
+void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
+	       const char *fmt, ...)
+{
+	struct audit_buffer *ab;
+	va_list args;
+
+	ab = audit_log_start(ctx, gfp_mask, type);
+	if (ab) {
+		va_start(args, fmt);
+		audit_log_vformat(ab, fmt, args);
+		va_end(args);
+		audit_log_end(ab);
+	}
+}
+
+#ifdef CONFIG_SECURITY
+/**
+ * audit_log_secctx - Converts and logs SELinux context
+ * @ab: audit_buffer
+ * @secid: security number
+ *
+ * This is a helper function that calls security_secid_to_secctx to convert
+ * secid to secctx and then adds the (converted) SELinux context to the audit
+ * log by calling audit_log_format, thus also preventing leak of internal secid
+ * to userspace. If secid cannot be converted audit_panic is called.
+ */
+void audit_log_secctx(struct audit_buffer *ab, u32 secid)
+{
+	u32 len;
+	char *secctx;
+
+	if (security_secid_to_secctx(secid, &secctx, &len)) {
+		audit_panic("Cannot convert secid to context");
+	} else {
+		audit_log_format(ab, " obj=%s", secctx);
+		security_release_secctx(secctx, len);
+	}
+}
+EXPORT_SYMBOL(audit_log_secctx);
+#endif
+
+EXPORT_SYMBOL(audit_log_start);
+EXPORT_SYMBOL(audit_log_end);
+EXPORT_SYMBOL(audit_log_format);
+EXPORT_SYMBOL(audit_log);
diff --git a/kernel/audit.h b/kernel/audit.h
new file mode 100644
index 00000000000..81676680337
--- /dev/null
+++ b/kernel/audit.h
@@ -0,0 +1,166 @@
+/* audit -- definition of audit_context structure and supporting types 
+ *
+ * Copyright 2003-2004 Red Hat, Inc.
+ * Copyright 2005 Hewlett-Packard Development Company, L.P.
+ * Copyright 2005 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/fs.h>
+#include <linux/audit.h>
+#include <linux/skbuff.h>
+
+/* 0 = no checking
+   1 = put_count checking
+   2 = verbose put_count checking
+*/
+#define AUDIT_DEBUG 0
+
+/* At task start time, the audit_state is set in the audit_context using
+   a per-task filter.  At syscall entry, the audit_state is augmented by
+   the syscall filter. */
+enum audit_state {
+	AUDIT_DISABLED,		/* Do not create per-task audit_context.
+				 * No syscall-specific audit records can
+				 * be generated. */
+	AUDIT_BUILD_CONTEXT,	/* Create the per-task audit_context,
+				 * and fill it in at syscall
+				 * entry time.  This makes a full
+				 * syscall record available if some
+				 * other part of the kernel decides it
+				 * should be recorded. */
+	AUDIT_RECORD_CONTEXT	/* Create the per-task audit_context,
+				 * always fill it in at syscall entry
+				 * time, and always write out the audit
+				 * record at syscall exit time.  */
+};
+
+/* Rule lists */
+struct audit_watch;
+struct audit_tree;
+struct audit_chunk;
+
+struct audit_entry {
+	struct list_head	list;
+	struct rcu_head		rcu;
+	struct audit_krule	rule;
+};
+
+#ifdef CONFIG_AUDIT
+extern int audit_enabled;
+extern int audit_ever_enabled;
+#endif
+
+extern int audit_pid;
+
+#define AUDIT_INODE_BUCKETS	32
+extern struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
+
+static inline int audit_hash_ino(u32 ino)
+{
+	return (ino & (AUDIT_INODE_BUCKETS-1));
+}
+
+extern int audit_match_class(int class, unsigned syscall);
+extern int audit_comparator(const u32 left, const u32 op, const u32 right);
+extern int audit_compare_dname_path(const char *dname, const char *path,
+				    int *dirlen);
+extern struct sk_buff *	    audit_make_reply(int pid, int seq, int type,
+					     int done, int multi,
+					     const void *payload, int size);
+extern void		    audit_panic(const char *message);
+
+struct audit_netlink_list {
+	int pid;
+	struct sk_buff_head q;
+};
+
+int audit_send_list(void *);
+
+extern int selinux_audit_rule_update(void);
+
+extern struct mutex audit_filter_mutex;
+extern void audit_free_rule_rcu(struct rcu_head *);
+extern struct list_head audit_filter_list[];
+
+extern struct audit_entry *audit_dupe_rule(struct audit_krule *old);
+
+/* audit watch functions */
+#ifdef CONFIG_AUDIT_WATCH
+extern void audit_put_watch(struct audit_watch *watch);
+extern void audit_get_watch(struct audit_watch *watch);
+extern int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op);
+extern int audit_add_watch(struct audit_krule *krule, struct list_head **list);
+extern void audit_remove_watch_rule(struct audit_krule *krule);
+extern char *audit_watch_path(struct audit_watch *watch);
+extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev);
+#else
+#define audit_put_watch(w) {}
+#define audit_get_watch(w) {}
+#define audit_to_watch(k, p, l, o) (-EINVAL)
+#define audit_add_watch(k, l) (-EINVAL)
+#define audit_remove_watch_rule(k) BUG()
+#define audit_watch_path(w) ""
+#define audit_watch_compare(w, i, d) 0
+
+#endif /* CONFIG_AUDIT_WATCH */
+
+#ifdef CONFIG_AUDIT_TREE
+extern struct audit_chunk *audit_tree_lookup(const struct inode *);
+extern void audit_put_chunk(struct audit_chunk *);
+extern int audit_tree_match(struct audit_chunk *, struct audit_tree *);
+extern int audit_make_tree(struct audit_krule *, char *, u32);
+extern int audit_add_tree_rule(struct audit_krule *);
+extern int audit_remove_tree_rule(struct audit_krule *);
+extern void audit_trim_trees(void);
+extern int audit_tag_tree(char *old, char *new);
+extern const char *audit_tree_path(struct audit_tree *);
+extern void audit_put_tree(struct audit_tree *);
+extern void audit_kill_trees(struct list_head *);
+#else
+#define audit_remove_tree_rule(rule) BUG()
+#define audit_add_tree_rule(rule) -EINVAL
+#define audit_make_tree(rule, str, op) -EINVAL
+#define audit_trim_trees() (void)0
+#define audit_put_tree(tree) (void)0
+#define audit_tag_tree(old, new) -EINVAL
+#define audit_tree_path(rule) ""	/* never called */
+#define audit_kill_trees(list) BUG()
+#endif
+
+extern char *audit_unpack_string(void **, size_t *, size_t);
+
+extern pid_t audit_sig_pid;
+extern uid_t audit_sig_uid;
+extern u32 audit_sig_sid;
+
+#ifdef CONFIG_AUDITSYSCALL
+extern int __audit_signal_info(int sig, struct task_struct *t);
+static inline int audit_signal_info(int sig, struct task_struct *t)
+{
+	if (unlikely((audit_pid && t->tgid == audit_pid) ||
+		     (audit_signals && !audit_dummy_context())))
+		return __audit_signal_info(sig, t);
+	return 0;
+}
+extern void audit_filter_inodes(struct task_struct *, struct audit_context *);
+extern struct list_head *audit_killed_trees(void);
+#else
+#define audit_signal_info(s,t) AUDIT_DISABLED
+#define audit_filter_inodes(t,c) AUDIT_DISABLED
+#endif
+
+extern struct mutex audit_cmd_mutex;
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
new file mode 100644
index 00000000000..5bf0790497e
--- /dev/null
+++ b/kernel/audit_tree.c
@@ -0,0 +1,951 @@
+#include "audit.h"
+#include <linux/fsnotify_backend.h>
+#include <linux/namei.h>
+#include <linux/mount.h>
+#include <linux/kthread.h>
+#include <linux/slab.h>
+
+struct audit_tree;
+struct audit_chunk;
+
+struct audit_tree {
+	atomic_t count;
+	int goner;
+	struct audit_chunk *root;
+	struct list_head chunks;
+	struct list_head rules;
+	struct list_head list;
+	struct list_head same_root;
+	struct rcu_head head;
+	char pathname[];
+};
+
+struct audit_chunk {
+	struct list_head hash;
+	struct fsnotify_mark mark;
+	struct list_head trees;		/* with root here */
+	int dead;
+	int count;
+	atomic_long_t refs;
+	struct rcu_head head;
+	struct node {
+		struct list_head list;
+		struct audit_tree *owner;
+		unsigned index;		/* index; upper bit indicates 'will prune' */
+	} owners[];
+};
+
+static LIST_HEAD(tree_list);
+static LIST_HEAD(prune_list);
+
+/*
+ * One struct chunk is attached to each inode of interest.
+ * We replace struct chunk on tagging/untagging.
+ * Rules have pointer to struct audit_tree.
+ * Rules have struct list_head rlist forming a list of rules over
+ * the same tree.
+ * References to struct chunk are collected at audit_inode{,_child}()
+ * time and used in AUDIT_TREE rule matching.
+ * These references are dropped at the same time we are calling
+ * audit_free_names(), etc.
+ *
+ * Cyclic lists galore:
+ * tree.chunks anchors chunk.owners[].list			hash_lock
+ * tree.rules anchors rule.rlist				audit_filter_mutex
+ * chunk.trees anchors tree.same_root				hash_lock
+ * chunk.hash is a hash with middle bits of watch.inode as
+ * a hash function.						RCU, hash_lock
+ *
+ * tree is refcounted; one reference for "some rules on rules_list refer to
+ * it", one for each chunk with pointer to it.
+ *
+ * chunk is refcounted by embedded fsnotify_mark + .refs (non-zero refcount
+ * of watch contributes 1 to .refs).
+ *
+ * node.index allows to get from node.list to containing chunk.
+ * MSB of that sucker is stolen to mark taggings that we might have to
+ * revert - several operations have very unpleasant cleanup logics and
+ * that makes a difference.  Some.
+ */
+
+static struct fsnotify_group *audit_tree_group;
+
+static struct audit_tree *alloc_tree(const char *s)
+{
+	struct audit_tree *tree;
+
+	tree = kmalloc(sizeof(struct audit_tree) + strlen(s) + 1, GFP_KERNEL);
+	if (tree) {
+		atomic_set(&tree->count, 1);
+		tree->goner = 0;
+		INIT_LIST_HEAD(&tree->chunks);
+		INIT_LIST_HEAD(&tree->rules);
+		INIT_LIST_HEAD(&tree->list);
+		INIT_LIST_HEAD(&tree->same_root);
+		tree->root = NULL;
+		strcpy(tree->pathname, s);
+	}
+	return tree;
+}
+
+static inline void get_tree(struct audit_tree *tree)
+{
+	atomic_inc(&tree->count);
+}
+
+static inline void put_tree(struct audit_tree *tree)
+{
+	if (atomic_dec_and_test(&tree->count))
+		kfree_rcu(tree, head);
+}
+
+/* to avoid bringing the entire thing in audit.h */
+const char *audit_tree_path(struct audit_tree *tree)
+{
+	return tree->pathname;
+}
+
+static void free_chunk(struct audit_chunk *chunk)
+{
+	int i;
+
+	for (i = 0; i < chunk->count; i++) {
+		if (chunk->owners[i].owner)
+			put_tree(chunk->owners[i].owner);
+	}
+	kfree(chunk);
+}
+
+void audit_put_chunk(struct audit_chunk *chunk)
+{
+	if (atomic_long_dec_and_test(&chunk->refs))
+		free_chunk(chunk);
+}
+
+static void __put_chunk(struct rcu_head *rcu)
+{
+	struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head);
+	audit_put_chunk(chunk);
+}
+
+static void audit_tree_destroy_watch(struct fsnotify_mark *entry)
+{
+	struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark);
+	call_rcu(&chunk->head, __put_chunk);
+}
+
+static struct audit_chunk *alloc_chunk(int count)
+{
+	struct audit_chunk *chunk;
+	size_t size;
+	int i;
+
+	size = offsetof(struct audit_chunk, owners) + count * sizeof(struct node);
+	chunk = kzalloc(size, GFP_KERNEL);
+	if (!chunk)
+		return NULL;
+
+	INIT_LIST_HEAD(&chunk->hash);
+	INIT_LIST_HEAD(&chunk->trees);
+	chunk->count = count;
+	atomic_long_set(&chunk->refs, 1);
+	for (i = 0; i < count; i++) {
+		INIT_LIST_HEAD(&chunk->owners[i].list);
+		chunk->owners[i].index = i;
+	}
+	fsnotify_init_mark(&chunk->mark, audit_tree_destroy_watch);
+	return chunk;
+}
+
+enum {HASH_SIZE = 128};
+static struct list_head chunk_hash_heads[HASH_SIZE];
+static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock);
+
+static inline struct list_head *chunk_hash(const struct inode *inode)
+{
+	unsigned long n = (unsigned long)inode / L1_CACHE_BYTES;
+	return chunk_hash_heads + n % HASH_SIZE;
+}
+
+/* hash_lock & entry->lock is held by caller */
+static void insert_hash(struct audit_chunk *chunk)
+{
+	struct fsnotify_mark *entry = &chunk->mark;
+	struct list_head *list;
+
+	if (!entry->i.inode)
+		return;
+	list = chunk_hash(entry->i.inode);
+	list_add_rcu(&chunk->hash, list);
+}
+
+/* called under rcu_read_lock */
+struct audit_chunk *audit_tree_lookup(const struct inode *inode)
+{
+	struct list_head *list = chunk_hash(inode);
+	struct audit_chunk *p;
+
+	list_for_each_entry_rcu(p, list, hash) {
+		/* mark.inode may have gone NULL, but who cares? */
+		if (p->mark.i.inode == inode) {
+			atomic_long_inc(&p->refs);
+			return p;
+		}
+	}
+	return NULL;
+}
+
+int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree)
+{
+	int n;
+	for (n = 0; n < chunk->count; n++)
+		if (chunk->owners[n].owner == tree)
+			return 1;
+	return 0;
+}
+
+/* tagging and untagging inodes with trees */
+
+static struct audit_chunk *find_chunk(struct node *p)
+{
+	int index = p->index & ~(1U<<31);
+	p -= index;
+	return container_of(p, struct audit_chunk, owners[0]);
+}
+
+static void untag_chunk(struct node *p)
+{
+	struct audit_chunk *chunk = find_chunk(p);
+	struct fsnotify_mark *entry = &chunk->mark;
+	struct audit_chunk *new = NULL;
+	struct audit_tree *owner;
+	int size = chunk->count - 1;
+	int i, j;
+
+	fsnotify_get_mark(entry);
+
+	spin_unlock(&hash_lock);
+
+	if (size)
+		new = alloc_chunk(size);
+
+	spin_lock(&entry->lock);
+	if (chunk->dead || !entry->i.inode) {
+		spin_unlock(&entry->lock);
+		if (new)
+			free_chunk(new);
+		goto out;
+	}
+
+	owner = p->owner;
+
+	if (!size) {
+		chunk->dead = 1;
+		spin_lock(&hash_lock);
+		list_del_init(&chunk->trees);
+		if (owner->root == chunk)
+			owner->root = NULL;
+		list_del_init(&p->list);
+		list_del_rcu(&chunk->hash);
+		spin_unlock(&hash_lock);
+		spin_unlock(&entry->lock);
+		fsnotify_destroy_mark(entry);
+		fsnotify_put_mark(entry);
+		goto out;
+	}
+
+	if (!new)
+		goto Fallback;
+
+	fsnotify_duplicate_mark(&new->mark, entry);
+	if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.i.inode, NULL, 1)) {
+		free_chunk(new);
+		goto Fallback;
+	}
+
+	chunk->dead = 1;
+	spin_lock(&hash_lock);
+	list_replace_init(&chunk->trees, &new->trees);
+	if (owner->root == chunk) {
+		list_del_init(&owner->same_root);
+		owner->root = NULL;
+	}
+
+	for (i = j = 0; j <= size; i++, j++) {
+		struct audit_tree *s;
+		if (&chunk->owners[j] == p) {
+			list_del_init(&p->list);
+			i--;
+			continue;
+		}
+		s = chunk->owners[j].owner;
+		new->owners[i].owner = s;
+		new->owners[i].index = chunk->owners[j].index - j + i;
+		if (!s) /* result of earlier fallback */
+			continue;
+		get_tree(s);
+		list_replace_init(&chunk->owners[j].list, &new->owners[i].list);
+	}
+
+	list_replace_rcu(&chunk->hash, &new->hash);
+	list_for_each_entry(owner, &new->trees, same_root)
+		owner->root = new;
+	spin_unlock(&hash_lock);
+	spin_unlock(&entry->lock);
+	fsnotify_destroy_mark(entry);
+	fsnotify_put_mark(entry);
+	goto out;
+
+Fallback:
+	// do the best we can
+	spin_lock(&hash_lock);
+	if (owner->root == chunk) {
+		list_del_init(&owner->same_root);
+		owner->root = NULL;
+	}
+	list_del_init(&p->list);
+	p->owner = NULL;
+	put_tree(owner);
+	spin_unlock(&hash_lock);
+	spin_unlock(&entry->lock);
+out:
+	fsnotify_put_mark(entry);
+	spin_lock(&hash_lock);
+}
+
+static int create_chunk(struct inode *inode, struct audit_tree *tree)
+{
+	struct fsnotify_mark *entry;
+	struct audit_chunk *chunk = alloc_chunk(1);
+	if (!chunk)
+		return -ENOMEM;
+
+	entry = &chunk->mark;
+	if (fsnotify_add_mark(entry, audit_tree_group, inode, NULL, 0)) {
+		free_chunk(chunk);
+		return -ENOSPC;
+	}
+
+	spin_lock(&entry->lock);
+	spin_lock(&hash_lock);
+	if (tree->goner) {
+		spin_unlock(&hash_lock);
+		chunk->dead = 1;
+		spin_unlock(&entry->lock);
+		fsnotify_destroy_mark(entry);
+		fsnotify_put_mark(entry);
+		return 0;
+	}
+	chunk->owners[0].index = (1U << 31);
+	chunk->owners[0].owner = tree;
+	get_tree(tree);
+	list_add(&chunk->owners[0].list, &tree->chunks);
+	if (!tree->root) {
+		tree->root = chunk;
+		list_add(&tree->same_root, &chunk->trees);
+	}
+	insert_hash(chunk);
+	spin_unlock(&hash_lock);
+	spin_unlock(&entry->lock);
+	return 0;
+}
+
+/* the first tagged inode becomes root of tree */
+static int tag_chunk(struct inode *inode, struct audit_tree *tree)
+{
+	struct fsnotify_mark *old_entry, *chunk_entry;
+	struct audit_tree *owner;
+	struct audit_chunk *chunk, *old;
+	struct node *p;
+	int n;
+
+	old_entry = fsnotify_find_inode_mark(audit_tree_group, inode);
+	if (!old_entry)
+		return create_chunk(inode, tree);
+
+	old = container_of(old_entry, struct audit_chunk, mark);
+
+	/* are we already there? */
+	spin_lock(&hash_lock);
+	for (n = 0; n < old->count; n++) {
+		if (old->owners[n].owner == tree) {
+			spin_unlock(&hash_lock);
+			fsnotify_put_mark(old_entry);
+			return 0;
+		}
+	}
+	spin_unlock(&hash_lock);
+
+	chunk = alloc_chunk(old->count + 1);
+	if (!chunk) {
+		fsnotify_put_mark(old_entry);
+		return -ENOMEM;
+	}
+
+	chunk_entry = &chunk->mark;
+
+	spin_lock(&old_entry->lock);
+	if (!old_entry->i.inode) {
+		/* old_entry is being shot, lets just lie */
+		spin_unlock(&old_entry->lock);
+		fsnotify_put_mark(old_entry);
+		free_chunk(chunk);
+		return -ENOENT;
+	}
+
+	fsnotify_duplicate_mark(chunk_entry, old_entry);
+	if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->i.inode, NULL, 1)) {
+		spin_unlock(&old_entry->lock);
+		free_chunk(chunk);
+		fsnotify_put_mark(old_entry);
+		return -ENOSPC;
+	}
+
+	/* even though we hold old_entry->lock, this is safe since chunk_entry->lock could NEVER have been grabbed before */
+	spin_lock(&chunk_entry->lock);
+	spin_lock(&hash_lock);
+
+	/* we now hold old_entry->lock, chunk_entry->lock, and hash_lock */
+	if (tree->goner) {
+		spin_unlock(&hash_lock);
+		chunk->dead = 1;
+		spin_unlock(&chunk_entry->lock);
+		spin_unlock(&old_entry->lock);
+
+		fsnotify_destroy_mark(chunk_entry);
+
+		fsnotify_put_mark(chunk_entry);
+		fsnotify_put_mark(old_entry);
+		return 0;
+	}
+	list_replace_init(&old->trees, &chunk->trees);
+	for (n = 0, p = chunk->owners; n < old->count; n++, p++) {
+		struct audit_tree *s = old->owners[n].owner;
+		p->owner = s;
+		p->index = old->owners[n].index;
+		if (!s) /* result of fallback in untag */
+			continue;
+		get_tree(s);
+		list_replace_init(&old->owners[n].list, &p->list);
+	}
+	p->index = (chunk->count - 1) | (1U<<31);
+	p->owner = tree;
+	get_tree(tree);
+	list_add(&p->list, &tree->chunks);
+	list_replace_rcu(&old->hash, &chunk->hash);
+	list_for_each_entry(owner, &chunk->trees, same_root)
+		owner->root = chunk;
+	old->dead = 1;
+	if (!tree->root) {
+		tree->root = chunk;
+		list_add(&tree->same_root, &chunk->trees);
+	}
+	spin_unlock(&hash_lock);
+	spin_unlock(&chunk_entry->lock);
+	spin_unlock(&old_entry->lock);
+	fsnotify_destroy_mark(old_entry);
+	fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */
+	fsnotify_put_mark(old_entry); /* and kill it */
+	return 0;
+}
+
+static void kill_rules(struct audit_tree *tree)
+{
+	struct audit_krule *rule, *next;
+	struct audit_entry *entry;
+	struct audit_buffer *ab;
+
+	list_for_each_entry_safe(rule, next, &tree->rules, rlist) {
+		entry = container_of(rule, struct audit_entry, rule);
+
+		list_del_init(&rule->rlist);
+		if (rule->tree) {
+			/* not a half-baked one */
+			ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+			audit_log_format(ab, "op=");
+			audit_log_string(ab, "remove rule");
+			audit_log_format(ab, " dir=");
+			audit_log_untrustedstring(ab, rule->tree->pathname);
+			audit_log_key(ab, rule->filterkey);
+			audit_log_format(ab, " list=%d res=1", rule->listnr);
+			audit_log_end(ab);
+			rule->tree = NULL;
+			list_del_rcu(&entry->list);
+			list_del(&entry->rule.list);
+			call_rcu(&entry->rcu, audit_free_rule_rcu);
+		}
+	}
+}
+
+/*
+ * finish killing struct audit_tree
+ */
+static void prune_one(struct audit_tree *victim)
+{
+	spin_lock(&hash_lock);
+	while (!list_empty(&victim->chunks)) {
+		struct node *p;
+
+		p = list_entry(victim->chunks.next, struct node, list);
+
+		untag_chunk(p);
+	}
+	spin_unlock(&hash_lock);
+	put_tree(victim);
+}
+
+/* trim the uncommitted chunks from tree */
+
+static void trim_marked(struct audit_tree *tree)
+{
+	struct list_head *p, *q;
+	spin_lock(&hash_lock);
+	if (tree->goner) {
+		spin_unlock(&hash_lock);
+		return;
+	}
+	/* reorder */
+	for (p = tree->chunks.next; p != &tree->chunks; p = q) {
+		struct node *node = list_entry(p, struct node, list);
+		q = p->next;
+		if (node->index & (1U<<31)) {
+			list_del_init(p);
+			list_add(p, &tree->chunks);
+		}
+	}
+
+	while (!list_empty(&tree->chunks)) {
+		struct node *node;
+
+		node = list_entry(tree->chunks.next, struct node, list);
+
+		/* have we run out of marked? */
+		if (!(node->index & (1U<<31)))
+			break;
+
+		untag_chunk(node);
+	}
+	if (!tree->root && !tree->goner) {
+		tree->goner = 1;
+		spin_unlock(&hash_lock);
+		mutex_lock(&audit_filter_mutex);
+		kill_rules(tree);
+		list_del_init(&tree->list);
+		mutex_unlock(&audit_filter_mutex);
+		prune_one(tree);
+	} else {
+		spin_unlock(&hash_lock);
+	}
+}
+
+static void audit_schedule_prune(void);
+
+/* called with audit_filter_mutex */
+int audit_remove_tree_rule(struct audit_krule *rule)
+{
+	struct audit_tree *tree;
+	tree = rule->tree;
+	if (tree) {
+		spin_lock(&hash_lock);
+		list_del_init(&rule->rlist);
+		if (list_empty(&tree->rules) && !tree->goner) {
+			tree->root = NULL;
+			list_del_init(&tree->same_root);
+			tree->goner = 1;
+			list_move(&tree->list, &prune_list);
+			rule->tree = NULL;
+			spin_unlock(&hash_lock);
+			audit_schedule_prune();
+			return 1;
+		}
+		rule->tree = NULL;
+		spin_unlock(&hash_lock);
+		return 1;
+	}
+	return 0;
+}
+
+static int compare_root(struct vfsmount *mnt, void *arg)
+{
+	return mnt->mnt_root->d_inode == arg;
+}
+
+void audit_trim_trees(void)
+{
+	struct list_head cursor;
+
+	mutex_lock(&audit_filter_mutex);
+	list_add(&cursor, &tree_list);
+	while (cursor.next != &tree_list) {
+		struct audit_tree *tree;
+		struct path path;
+		struct vfsmount *root_mnt;
+		struct node *node;
+		int err;
+
+		tree = container_of(cursor.next, struct audit_tree, list);
+		get_tree(tree);
+		list_del(&cursor);
+		list_add(&cursor, &tree->list);
+		mutex_unlock(&audit_filter_mutex);
+
+		err = kern_path(tree->pathname, 0, &path);
+		if (err)
+			goto skip_it;
+
+		root_mnt = collect_mounts(&path);
+		path_put(&path);
+		if (!root_mnt)
+			goto skip_it;
+
+		spin_lock(&hash_lock);
+		list_for_each_entry(node, &tree->chunks, list) {
+			struct audit_chunk *chunk = find_chunk(node);
+			/* this could be NULL if the watch is dying else where... */
+			struct inode *inode = chunk->mark.i.inode;
+			node->index |= 1U<<31;
+			if (iterate_mounts(compare_root, inode, root_mnt))
+				node->index &= ~(1U<<31);
+		}
+		spin_unlock(&hash_lock);
+		trim_marked(tree);
+		put_tree(tree);
+		drop_collected_mounts(root_mnt);
+skip_it:
+		mutex_lock(&audit_filter_mutex);
+	}
+	list_del(&cursor);
+	mutex_unlock(&audit_filter_mutex);
+}
+
+int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op)
+{
+
+	if (pathname[0] != '/' ||
+	    rule->listnr != AUDIT_FILTER_EXIT ||
+	    op != Audit_equal ||
+	    rule->inode_f || rule->watch || rule->tree)
+		return -EINVAL;
+	rule->tree = alloc_tree(pathname);
+	if (!rule->tree)
+		return -ENOMEM;
+	return 0;
+}
+
+void audit_put_tree(struct audit_tree *tree)
+{
+	put_tree(tree);
+}
+
+static int tag_mount(struct vfsmount *mnt, void *arg)
+{
+	return tag_chunk(mnt->mnt_root->d_inode, arg);
+}
+
+/* called with audit_filter_mutex */
+int audit_add_tree_rule(struct audit_krule *rule)
+{
+	struct audit_tree *seed = rule->tree, *tree;
+	struct path path;
+	struct vfsmount *mnt;
+	int err;
+
+	list_for_each_entry(tree, &tree_list, list) {
+		if (!strcmp(seed->pathname, tree->pathname)) {
+			put_tree(seed);
+			rule->tree = tree;
+			list_add(&rule->rlist, &tree->rules);
+			return 0;
+		}
+	}
+	tree = seed;
+	list_add(&tree->list, &tree_list);
+	list_add(&rule->rlist, &tree->rules);
+	/* do not set rule->tree yet */
+	mutex_unlock(&audit_filter_mutex);
+
+	err = kern_path(tree->pathname, 0, &path);
+	if (err)
+		goto Err;
+	mnt = collect_mounts(&path);
+	path_put(&path);
+	if (!mnt) {
+		err = -ENOMEM;
+		goto Err;
+	}
+
+	get_tree(tree);
+	err = iterate_mounts(tag_mount, tree, mnt);
+	drop_collected_mounts(mnt);
+
+	if (!err) {
+		struct node *node;
+		spin_lock(&hash_lock);
+		list_for_each_entry(node, &tree->chunks, list)
+			node->index &= ~(1U<<31);
+		spin_unlock(&hash_lock);
+	} else {
+		trim_marked(tree);
+		goto Err;
+	}
+
+	mutex_lock(&audit_filter_mutex);
+	if (list_empty(&rule->rlist)) {
+		put_tree(tree);
+		return -ENOENT;
+	}
+	rule->tree = tree;
+	put_tree(tree);
+
+	return 0;
+Err:
+	mutex_lock(&audit_filter_mutex);
+	list_del_init(&tree->list);
+	list_del_init(&tree->rules);
+	put_tree(tree);
+	return err;
+}
+
+int audit_tag_tree(char *old, char *new)
+{
+	struct list_head cursor, barrier;
+	int failed = 0;
+	struct path path1, path2;
+	struct vfsmount *tagged;
+	int err;
+
+	err = kern_path(new, 0, &path2);
+	if (err)
+		return err;
+	tagged = collect_mounts(&path2);
+	path_put(&path2);
+	if (!tagged)
+		return -ENOMEM;
+
+	err = kern_path(old, 0, &path1);
+	if (err) {
+		drop_collected_mounts(tagged);
+		return err;
+	}
+
+	mutex_lock(&audit_filter_mutex);
+	list_add(&barrier, &tree_list);
+	list_add(&cursor, &barrier);
+
+	while (cursor.next != &tree_list) {
+		struct audit_tree *tree;
+		int good_one = 0;
+
+		tree = container_of(cursor.next, struct audit_tree, list);
+		get_tree(tree);
+		list_del(&cursor);
+		list_add(&cursor, &tree->list);
+		mutex_unlock(&audit_filter_mutex);
+
+		err = kern_path(tree->pathname, 0, &path2);
+		if (!err) {
+			good_one = path_is_under(&path1, &path2);
+			path_put(&path2);
+		}
+
+		if (!good_one) {
+			put_tree(tree);
+			mutex_lock(&audit_filter_mutex);
+			continue;
+		}
+
+		failed = iterate_mounts(tag_mount, tree, tagged);
+		if (failed) {
+			put_tree(tree);
+			mutex_lock(&audit_filter_mutex);
+			break;
+		}
+
+		mutex_lock(&audit_filter_mutex);
+		spin_lock(&hash_lock);
+		if (!tree->goner) {
+			list_del(&tree->list);
+			list_add(&tree->list, &tree_list);
+		}
+		spin_unlock(&hash_lock);
+		put_tree(tree);
+	}
+
+	while (barrier.prev != &tree_list) {
+		struct audit_tree *tree;
+
+		tree = container_of(barrier.prev, struct audit_tree, list);
+		get_tree(tree);
+		list_del(&tree->list);
+		list_add(&tree->list, &barrier);
+		mutex_unlock(&audit_filter_mutex);
+
+		if (!failed) {
+			struct node *node;
+			spin_lock(&hash_lock);
+			list_for_each_entry(node, &tree->chunks, list)
+				node->index &= ~(1U<<31);
+			spin_unlock(&hash_lock);
+		} else {
+			trim_marked(tree);
+		}
+
+		put_tree(tree);
+		mutex_lock(&audit_filter_mutex);
+	}
+	list_del(&barrier);
+	list_del(&cursor);
+	mutex_unlock(&audit_filter_mutex);
+	path_put(&path1);
+	drop_collected_mounts(tagged);
+	return failed;
+}
+
+/*
+ * That gets run when evict_chunk() ends up needing to kill audit_tree.
+ * Runs from a separate thread.
+ */
+static int prune_tree_thread(void *unused)
+{
+	mutex_lock(&audit_cmd_mutex);
+	mutex_lock(&audit_filter_mutex);
+
+	while (!list_empty(&prune_list)) {
+		struct audit_tree *victim;
+
+		victim = list_entry(prune_list.next, struct audit_tree, list);
+		list_del_init(&victim->list);
+
+		mutex_unlock(&audit_filter_mutex);
+
+		prune_one(victim);
+
+		mutex_lock(&audit_filter_mutex);
+	}
+
+	mutex_unlock(&audit_filter_mutex);
+	mutex_unlock(&audit_cmd_mutex);
+	return 0;
+}
+
+static void audit_schedule_prune(void)
+{
+	kthread_run(prune_tree_thread, NULL, "audit_prune_tree");
+}
+
+/*
+ * ... and that one is done if evict_chunk() decides to delay until the end
+ * of syscall.  Runs synchronously.
+ */
+void audit_kill_trees(struct list_head *list)
+{
+	mutex_lock(&audit_cmd_mutex);
+	mutex_lock(&audit_filter_mutex);
+
+	while (!list_empty(list)) {
+		struct audit_tree *victim;
+
+		victim = list_entry(list->next, struct audit_tree, list);
+		kill_rules(victim);
+		list_del_init(&victim->list);
+
+		mutex_unlock(&audit_filter_mutex);
+
+		prune_one(victim);
+
+		mutex_lock(&audit_filter_mutex);
+	}
+
+	mutex_unlock(&audit_filter_mutex);
+	mutex_unlock(&audit_cmd_mutex);
+}
+
+/*
+ *  Here comes the stuff asynchronous to auditctl operations
+ */
+
+static void evict_chunk(struct audit_chunk *chunk)
+{
+	struct audit_tree *owner;
+	struct list_head *postponed = audit_killed_trees();
+	int need_prune = 0;
+	int n;
+
+	if (chunk->dead)
+		return;
+
+	chunk->dead = 1;
+	mutex_lock(&audit_filter_mutex);
+	spin_lock(&hash_lock);
+	while (!list_empty(&chunk->trees)) {
+		owner = list_entry(chunk->trees.next,
+				   struct audit_tree, same_root);
+		owner->goner = 1;
+		owner->root = NULL;
+		list_del_init(&owner->same_root);
+		spin_unlock(&hash_lock);
+		if (!postponed) {
+			kill_rules(owner);
+			list_move(&owner->list, &prune_list);
+			need_prune = 1;
+		} else {
+			list_move(&owner->list, postponed);
+		}
+		spin_lock(&hash_lock);
+	}
+	list_del_rcu(&chunk->hash);
+	for (n = 0; n < chunk->count; n++)
+		list_del_init(&chunk->owners[n].list);
+	spin_unlock(&hash_lock);
+	if (need_prune)
+		audit_schedule_prune();
+	mutex_unlock(&audit_filter_mutex);
+}
+
+static int audit_tree_handle_event(struct fsnotify_group *group,
+				   struct fsnotify_mark *inode_mark,
+				   struct fsnotify_mark *vfsmonut_mark,
+				   struct fsnotify_event *event)
+{
+	BUG();
+	return -EOPNOTSUPP;
+}
+
+static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify_group *group)
+{
+	struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark);
+
+	evict_chunk(chunk);
+	fsnotify_put_mark(entry);
+}
+
+static bool audit_tree_send_event(struct fsnotify_group *group, struct inode *inode,
+				  struct fsnotify_mark *inode_mark,
+				  struct fsnotify_mark *vfsmount_mark,
+				  __u32 mask, void *data, int data_type)
+{
+	return false;
+}
+
+static const struct fsnotify_ops audit_tree_ops = {
+	.handle_event = audit_tree_handle_event,
+	.should_send_event = audit_tree_send_event,
+	.free_group_priv = NULL,
+	.free_event_priv = NULL,
+	.freeing_mark = audit_tree_freeing_mark,
+};
+
+static int __init audit_tree_init(void)
+{
+	int i;
+
+	audit_tree_group = fsnotify_alloc_group(&audit_tree_ops);
+	if (IS_ERR(audit_tree_group))
+		audit_panic("cannot initialize fsnotify group for rectree watches");
+
+	for (i = 0; i < HASH_SIZE; i++)
+		INIT_LIST_HEAD(&chunk_hash_heads[i]);
+
+	return 0;
+}
+__initcall(audit_tree_init);
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
new file mode 100644
index 00000000000..e683869365d
--- /dev/null
+++ b/kernel/audit_watch.c
@@ -0,0 +1,547 @@
+/* audit_watch.c -- watching inodes
+ *
+ * Copyright 2003-2009 Red Hat, Inc.
+ * Copyright 2005 Hewlett-Packard Development Company, L.P.
+ * Copyright 2005 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/audit.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/fs.h>
+#include <linux/fsnotify_backend.h>
+#include <linux/namei.h>
+#include <linux/netlink.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include "audit.h"
+
+/*
+ * Reference counting:
+ *
+ * audit_parent: lifetime is from audit_init_parent() to receipt of an FS_IGNORED
+ * 	event.  Each audit_watch holds a reference to its associated parent.
+ *
+ * audit_watch: if added to lists, lifetime is from audit_init_watch() to
+ * 	audit_remove_watch().  Additionally, an audit_watch may exist
+ * 	temporarily to assist in searching existing filter data.  Each
+ * 	audit_krule holds a reference to its associated watch.
+ */
+
+struct audit_watch {
+	atomic_t		count;	/* reference count */
+	dev_t			dev;	/* associated superblock device */
+	char			*path;	/* insertion path */
+	unsigned long		ino;	/* associated inode number */
+	struct audit_parent	*parent; /* associated parent */
+	struct list_head	wlist;	/* entry in parent->watches list */
+	struct list_head	rules;	/* anchor for krule->rlist */
+};
+
+struct audit_parent {
+	struct list_head	watches; /* anchor for audit_watch->wlist */
+	struct fsnotify_mark mark; /* fsnotify mark on the inode */
+};
+
+/* fsnotify handle. */
+static struct fsnotify_group *audit_watch_group;
+
+/* fsnotify events we care about. */
+#define AUDIT_FS_WATCH (FS_MOVE | FS_CREATE | FS_DELETE | FS_DELETE_SELF |\
+			FS_MOVE_SELF | FS_EVENT_ON_CHILD)
+
+static void audit_free_parent(struct audit_parent *parent)
+{
+	WARN_ON(!list_empty(&parent->watches));
+	kfree(parent);
+}
+
+static void audit_watch_free_mark(struct fsnotify_mark *entry)
+{
+	struct audit_parent *parent;
+
+	parent = container_of(entry, struct audit_parent, mark);
+	audit_free_parent(parent);
+}
+
+static void audit_get_parent(struct audit_parent *parent)
+{
+	if (likely(parent))
+		fsnotify_get_mark(&parent->mark);
+}
+
+static void audit_put_parent(struct audit_parent *parent)
+{
+	if (likely(parent))
+		fsnotify_put_mark(&parent->mark);
+}
+
+/*
+ * Find and return the audit_parent on the given inode.  If found a reference
+ * is taken on this parent.
+ */
+static inline struct audit_parent *audit_find_parent(struct inode *inode)
+{
+	struct audit_parent *parent = NULL;
+	struct fsnotify_mark *entry;
+
+	entry = fsnotify_find_inode_mark(audit_watch_group, inode);
+	if (entry)
+		parent = container_of(entry, struct audit_parent, mark);
+
+	return parent;
+}
+
+void audit_get_watch(struct audit_watch *watch)
+{
+	atomic_inc(&watch->count);
+}
+
+void audit_put_watch(struct audit_watch *watch)
+{
+	if (atomic_dec_and_test(&watch->count)) {
+		WARN_ON(watch->parent);
+		WARN_ON(!list_empty(&watch->rules));
+		kfree(watch->path);
+		kfree(watch);
+	}
+}
+
+static void audit_remove_watch(struct audit_watch *watch)
+{
+	list_del(&watch->wlist);
+	audit_put_parent(watch->parent);
+	watch->parent = NULL;
+	audit_put_watch(watch); /* match initial get */
+}
+
+char *audit_watch_path(struct audit_watch *watch)
+{
+	return watch->path;
+}
+
+int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev)
+{
+	return (watch->ino != (unsigned long)-1) &&
+		(watch->ino == ino) &&
+		(watch->dev == dev);
+}
+
+/* Initialize a parent watch entry. */
+static struct audit_parent *audit_init_parent(struct path *path)
+{
+	struct inode *inode = path->dentry->d_inode;
+	struct audit_parent *parent;
+	int ret;
+
+	parent = kzalloc(sizeof(*parent), GFP_KERNEL);
+	if (unlikely(!parent))
+		return ERR_PTR(-ENOMEM);
+
+	INIT_LIST_HEAD(&parent->watches);
+
+	fsnotify_init_mark(&parent->mark, audit_watch_free_mark);
+	parent->mark.mask = AUDIT_FS_WATCH;
+	ret = fsnotify_add_mark(&parent->mark, audit_watch_group, inode, NULL, 0);
+	if (ret < 0) {
+		audit_free_parent(parent);
+		return ERR_PTR(ret);
+	}
+
+	return parent;
+}
+
+/* Initialize a watch entry. */
+static struct audit_watch *audit_init_watch(char *path)
+{
+	struct audit_watch *watch;
+
+	watch = kzalloc(sizeof(*watch), GFP_KERNEL);
+	if (unlikely(!watch))
+		return ERR_PTR(-ENOMEM);
+
+	INIT_LIST_HEAD(&watch->rules);
+	atomic_set(&watch->count, 1);
+	watch->path = path;
+	watch->dev = (dev_t)-1;
+	watch->ino = (unsigned long)-1;
+
+	return watch;
+}
+
+/* Translate a watch string to kernel respresentation. */
+int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op)
+{
+	struct audit_watch *watch;
+
+	if (!audit_watch_group)
+		return -EOPNOTSUPP;
+
+	if (path[0] != '/' || path[len-1] == '/' ||
+	    krule->listnr != AUDIT_FILTER_EXIT ||
+	    op != Audit_equal ||
+	    krule->inode_f || krule->watch || krule->tree)
+		return -EINVAL;
+
+	watch = audit_init_watch(path);
+	if (IS_ERR(watch))
+		return PTR_ERR(watch);
+
+	audit_get_watch(watch);
+	krule->watch = watch;
+
+	return 0;
+}
+
+/* Duplicate the given audit watch.  The new watch's rules list is initialized
+ * to an empty list and wlist is undefined. */
+static struct audit_watch *audit_dupe_watch(struct audit_watch *old)
+{
+	char *path;
+	struct audit_watch *new;
+
+	path = kstrdup(old->path, GFP_KERNEL);
+	if (unlikely(!path))
+		return ERR_PTR(-ENOMEM);
+
+	new = audit_init_watch(path);
+	if (IS_ERR(new)) {
+		kfree(path);
+		goto out;
+	}
+
+	new->dev = old->dev;
+	new->ino = old->ino;
+	audit_get_parent(old->parent);
+	new->parent = old->parent;
+
+out:
+	return new;
+}
+
+static void audit_watch_log_rule_change(struct audit_krule *r, struct audit_watch *w, char *op)
+{
+	if (audit_enabled) {
+		struct audit_buffer *ab;
+		ab = audit_log_start(NULL, GFP_NOFS, AUDIT_CONFIG_CHANGE);
+		audit_log_format(ab, "auid=%u ses=%u op=",
+				 audit_get_loginuid(current),
+				 audit_get_sessionid(current));
+		audit_log_string(ab, op);
+		audit_log_format(ab, " path=");
+		audit_log_untrustedstring(ab, w->path);
+		audit_log_key(ab, r->filterkey);
+		audit_log_format(ab, " list=%d res=1", r->listnr);
+		audit_log_end(ab);
+	}
+}
+
+/* Update inode info in audit rules based on filesystem event. */
+static void audit_update_watch(struct audit_parent *parent,
+			       const char *dname, dev_t dev,
+			       unsigned long ino, unsigned invalidating)
+{
+	struct audit_watch *owatch, *nwatch, *nextw;
+	struct audit_krule *r, *nextr;
+	struct audit_entry *oentry, *nentry;
+
+	mutex_lock(&audit_filter_mutex);
+	/* Run all of the watches on this parent looking for the one that
+	 * matches the given dname */
+	list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) {
+		if (audit_compare_dname_path(dname, owatch->path, NULL))
+			continue;
+
+		/* If the update involves invalidating rules, do the inode-based
+		 * filtering now, so we don't omit records. */
+		if (invalidating && !audit_dummy_context())
+			audit_filter_inodes(current, current->audit_context);
+
+		/* updating ino will likely change which audit_hash_list we
+		 * are on so we need a new watch for the new list */
+		nwatch = audit_dupe_watch(owatch);
+		if (IS_ERR(nwatch)) {
+			mutex_unlock(&audit_filter_mutex);
+			audit_panic("error updating watch, skipping");
+			return;
+		}
+		nwatch->dev = dev;
+		nwatch->ino = ino;
+
+		list_for_each_entry_safe(r, nextr, &owatch->rules, rlist) {
+
+			oentry = container_of(r, struct audit_entry, rule);
+			list_del(&oentry->rule.rlist);
+			list_del_rcu(&oentry->list);
+
+			nentry = audit_dupe_rule(&oentry->rule);
+			if (IS_ERR(nentry)) {
+				list_del(&oentry->rule.list);
+				audit_panic("error updating watch, removing");
+			} else {
+				int h = audit_hash_ino((u32)ino);
+
+				/*
+				 * nentry->rule.watch == oentry->rule.watch so
+				 * we must drop that reference and set it to our
+				 * new watch.
+				 */
+				audit_put_watch(nentry->rule.watch);
+				audit_get_watch(nwatch);
+				nentry->rule.watch = nwatch;
+				list_add(&nentry->rule.rlist, &nwatch->rules);
+				list_add_rcu(&nentry->list, &audit_inode_hash[h]);
+				list_replace(&oentry->rule.list,
+					     &nentry->rule.list);
+			}
+
+			audit_watch_log_rule_change(r, owatch, "updated rules");
+
+			call_rcu(&oentry->rcu, audit_free_rule_rcu);
+		}
+
+		audit_remove_watch(owatch);
+		goto add_watch_to_parent; /* event applies to a single watch */
+	}
+	mutex_unlock(&audit_filter_mutex);
+	return;
+
+add_watch_to_parent:
+	list_add(&nwatch->wlist, &parent->watches);
+	mutex_unlock(&audit_filter_mutex);
+	return;
+}
+
+/* Remove all watches & rules associated with a parent that is going away. */
+static void audit_remove_parent_watches(struct audit_parent *parent)
+{
+	struct audit_watch *w, *nextw;
+	struct audit_krule *r, *nextr;
+	struct audit_entry *e;
+
+	mutex_lock(&audit_filter_mutex);
+	list_for_each_entry_safe(w, nextw, &parent->watches, wlist) {
+		list_for_each_entry_safe(r, nextr, &w->rules, rlist) {
+			e = container_of(r, struct audit_entry, rule);
+			audit_watch_log_rule_change(r, w, "remove rule");
+			list_del(&r->rlist);
+			list_del(&r->list);
+			list_del_rcu(&e->list);
+			call_rcu(&e->rcu, audit_free_rule_rcu);
+		}
+		audit_remove_watch(w);
+	}
+	mutex_unlock(&audit_filter_mutex);
+
+	fsnotify_destroy_mark(&parent->mark);
+}
+
+/* Get path information necessary for adding watches. */
+static int audit_get_nd(struct audit_watch *watch, struct path *parent)
+{
+	struct nameidata nd;
+	struct dentry *d;
+	int err;
+
+	err = kern_path_parent(watch->path, &nd);
+	if (err)
+		return err;
+
+	if (nd.last_type != LAST_NORM) {
+		path_put(&nd.path);
+		return -EINVAL;
+	}
+
+	mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+	d = lookup_one_len(nd.last.name, nd.path.dentry, nd.last.len);
+	if (IS_ERR(d)) {
+		mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+		path_put(&nd.path);
+		return PTR_ERR(d);
+	}
+	if (d->d_inode) {
+		/* update watch filter fields */
+		watch->dev = d->d_inode->i_sb->s_dev;
+		watch->ino = d->d_inode->i_ino;
+	}
+	mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
+
+	*parent = nd.path;
+	dput(d);
+	return 0;
+}
+
+/* Associate the given rule with an existing parent.
+ * Caller must hold audit_filter_mutex. */
+static void audit_add_to_parent(struct audit_krule *krule,
+				struct audit_parent *parent)
+{
+	struct audit_watch *w, *watch = krule->watch;
+	int watch_found = 0;
+
+	BUG_ON(!mutex_is_locked(&audit_filter_mutex));
+
+	list_for_each_entry(w, &parent->watches, wlist) {
+		if (strcmp(watch->path, w->path))
+			continue;
+
+		watch_found = 1;
+
+		/* put krule's and initial refs to temporary watch */
+		audit_put_watch(watch);
+		audit_put_watch(watch);
+
+		audit_get_watch(w);
+		krule->watch = watch = w;
+		break;
+	}
+
+	if (!watch_found) {
+		audit_get_parent(parent);
+		watch->parent = parent;
+
+		list_add(&watch->wlist, &parent->watches);
+	}
+	list_add(&krule->rlist, &watch->rules);
+}
+
+/* Find a matching watch entry, or add this one.
+ * Caller must hold audit_filter_mutex. */
+int audit_add_watch(struct audit_krule *krule, struct list_head **list)
+{
+	struct audit_watch *watch = krule->watch;
+	struct audit_parent *parent;
+	struct path parent_path;
+	int h, ret = 0;
+
+	mutex_unlock(&audit_filter_mutex);
+
+	/* Avoid calling path_lookup under audit_filter_mutex. */
+	ret = audit_get_nd(watch, &parent_path);
+
+	/* caller expects mutex locked */
+	mutex_lock(&audit_filter_mutex);
+
+	if (ret)
+		return ret;
+
+	/* either find an old parent or attach a new one */
+	parent = audit_find_parent(parent_path.dentry->d_inode);
+	if (!parent) {
+		parent = audit_init_parent(&parent_path);
+		if (IS_ERR(parent)) {
+			ret = PTR_ERR(parent);
+			goto error;
+		}
+	}
+
+	audit_add_to_parent(krule, parent);
+
+	/* match get in audit_find_parent or audit_init_parent */
+	audit_put_parent(parent);
+
+	h = audit_hash_ino((u32)watch->ino);
+	*list = &audit_inode_hash[h];
+error:
+	path_put(&parent_path);
+	return ret;
+}
+
+void audit_remove_watch_rule(struct audit_krule *krule)
+{
+	struct audit_watch *watch = krule->watch;
+	struct audit_parent *parent = watch->parent;
+
+	list_del(&krule->rlist);
+
+	if (list_empty(&watch->rules)) {
+		audit_remove_watch(watch);
+
+		if (list_empty(&parent->watches)) {
+			audit_get_parent(parent);
+			fsnotify_destroy_mark(&parent->mark);
+			audit_put_parent(parent);
+		}
+	}
+}
+
+static bool audit_watch_should_send_event(struct fsnotify_group *group, struct inode *inode,
+					  struct fsnotify_mark *inode_mark,
+					  struct fsnotify_mark *vfsmount_mark,
+					  __u32 mask, void *data, int data_type)
+{
+       return true;
+}
+
+/* Update watch data in audit rules based on fsnotify events. */
+static int audit_watch_handle_event(struct fsnotify_group *group,
+				    struct fsnotify_mark *inode_mark,
+				    struct fsnotify_mark *vfsmount_mark,
+				    struct fsnotify_event *event)
+{
+	struct inode *inode;
+	__u32 mask = event->mask;
+	const char *dname = event->file_name;
+	struct audit_parent *parent;
+
+	parent = container_of(inode_mark, struct audit_parent, mark);
+
+	BUG_ON(group != audit_watch_group);
+
+	switch (event->data_type) {
+	case (FSNOTIFY_EVENT_PATH):
+		inode = event->path.dentry->d_inode;
+		break;
+	case (FSNOTIFY_EVENT_INODE):
+		inode = event->inode;
+		break;
+	default:
+		BUG();
+		inode = NULL;
+		break;
+	};
+
+	if (mask & (FS_CREATE|FS_MOVED_TO) && inode)
+		audit_update_watch(parent, dname, inode->i_sb->s_dev, inode->i_ino, 0);
+	else if (mask & (FS_DELETE|FS_MOVED_FROM))
+		audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1);
+	else if (mask & (FS_DELETE_SELF|FS_UNMOUNT|FS_MOVE_SELF))
+		audit_remove_parent_watches(parent);
+
+	return 0;
+}
+
+static const struct fsnotify_ops audit_watch_fsnotify_ops = {
+	.should_send_event = 	audit_watch_should_send_event,
+	.handle_event = 	audit_watch_handle_event,
+	.free_group_priv = 	NULL,
+	.freeing_mark = 	NULL,
+	.free_event_priv = 	NULL,
+};
+
+static int __init audit_watch_init(void)
+{
+	audit_watch_group = fsnotify_alloc_group(&audit_watch_fsnotify_ops);
+	if (IS_ERR(audit_watch_group)) {
+		audit_watch_group = NULL;
+		audit_panic("cannot create audit fsnotify group");
+	}
+	return 0;
+}
+device_initcall(audit_watch_init);
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
new file mode 100644
index 00000000000..a6c3f1abd20
--- /dev/null
+++ b/kernel/auditfilter.c
@@ -0,0 +1,1390 @@
+/* auditfilter.c -- filtering of audit events
+ *
+ * Copyright 2003-2004 Red Hat, Inc.
+ * Copyright 2005 Hewlett-Packard Development Company, L.P.
+ * Copyright 2005 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/audit.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/netlink.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include "audit.h"
+
+/*
+ * Locking model:
+ *
+ * audit_filter_mutex:
+ * 		Synchronizes writes and blocking reads of audit's filterlist
+ * 		data.  Rcu is used to traverse the filterlist and access
+ * 		contents of structs audit_entry, audit_watch and opaque
+ * 		LSM rules during filtering.  If modified, these structures
+ * 		must be copied and replace their counterparts in the filterlist.
+ * 		An audit_parent struct is not accessed during filtering, so may
+ * 		be written directly provided audit_filter_mutex is held.
+ */
+
+/* Audit filter lists, defined in <linux/audit.h> */
+struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
+	LIST_HEAD_INIT(audit_filter_list[0]),
+	LIST_HEAD_INIT(audit_filter_list[1]),
+	LIST_HEAD_INIT(audit_filter_list[2]),
+	LIST_HEAD_INIT(audit_filter_list[3]),
+	LIST_HEAD_INIT(audit_filter_list[4]),
+	LIST_HEAD_INIT(audit_filter_list[5]),
+#if AUDIT_NR_FILTERS != 6
+#error Fix audit_filter_list initialiser
+#endif
+};
+static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = {
+	LIST_HEAD_INIT(audit_rules_list[0]),
+	LIST_HEAD_INIT(audit_rules_list[1]),
+	LIST_HEAD_INIT(audit_rules_list[2]),
+	LIST_HEAD_INIT(audit_rules_list[3]),
+	LIST_HEAD_INIT(audit_rules_list[4]),
+	LIST_HEAD_INIT(audit_rules_list[5]),
+};
+
+DEFINE_MUTEX(audit_filter_mutex);
+
+static inline void audit_free_rule(struct audit_entry *e)
+{
+	int i;
+	struct audit_krule *erule = &e->rule;
+
+	/* some rules don't have associated watches */
+	if (erule->watch)
+		audit_put_watch(erule->watch);
+	if (erule->fields)
+		for (i = 0; i < erule->field_count; i++) {
+			struct audit_field *f = &erule->fields[i];
+			kfree(f->lsm_str);
+			security_audit_rule_free(f->lsm_rule);
+		}
+	kfree(erule->fields);
+	kfree(erule->filterkey);
+	kfree(e);
+}
+
+void audit_free_rule_rcu(struct rcu_head *head)
+{
+	struct audit_entry *e = container_of(head, struct audit_entry, rcu);
+	audit_free_rule(e);
+}
+
+/* Initialize an audit filterlist entry. */
+static inline struct audit_entry *audit_init_entry(u32 field_count)
+{
+	struct audit_entry *entry;
+	struct audit_field *fields;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (unlikely(!entry))
+		return NULL;
+
+	fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL);
+	if (unlikely(!fields)) {
+		kfree(entry);
+		return NULL;
+	}
+	entry->rule.fields = fields;
+
+	return entry;
+}
+
+/* Unpack a filter field's string representation from user-space
+ * buffer. */
+char *audit_unpack_string(void **bufp, size_t *remain, size_t len)
+{
+	char *str;
+
+	if (!*bufp || (len == 0) || (len > *remain))
+		return ERR_PTR(-EINVAL);
+
+	/* Of the currently implemented string fields, PATH_MAX
+	 * defines the longest valid length.
+	 */
+	if (len > PATH_MAX)
+		return ERR_PTR(-ENAMETOOLONG);
+
+	str = kmalloc(len + 1, GFP_KERNEL);
+	if (unlikely(!str))
+		return ERR_PTR(-ENOMEM);
+
+	memcpy(str, *bufp, len);
+	str[len] = 0;
+	*bufp += len;
+	*remain -= len;
+
+	return str;
+}
+
+/* Translate an inode field to kernel respresentation. */
+static inline int audit_to_inode(struct audit_krule *krule,
+				 struct audit_field *f)
+{
+	if (krule->listnr != AUDIT_FILTER_EXIT ||
+	    krule->watch || krule->inode_f || krule->tree ||
+	    (f->op != Audit_equal && f->op != Audit_not_equal))
+		return -EINVAL;
+
+	krule->inode_f = f;
+	return 0;
+}
+
+static __u32 *classes[AUDIT_SYSCALL_CLASSES];
+
+int __init audit_register_class(int class, unsigned *list)
+{
+	__u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL);
+	if (!p)
+		return -ENOMEM;
+	while (*list != ~0U) {
+		unsigned n = *list++;
+		if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) {
+			kfree(p);
+			return -EINVAL;
+		}
+		p[AUDIT_WORD(n)] |= AUDIT_BIT(n);
+	}
+	if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) {
+		kfree(p);
+		return -EINVAL;
+	}
+	classes[class] = p;
+	return 0;
+}
+
+int audit_match_class(int class, unsigned syscall)
+{
+	if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32))
+		return 0;
+	if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class]))
+		return 0;
+	return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall);
+}
+
+#ifdef CONFIG_AUDITSYSCALL
+static inline int audit_match_class_bits(int class, u32 *mask)
+{
+	int i;
+
+	if (classes[class]) {
+		for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
+			if (mask[i] & classes[class][i])
+				return 0;
+	}
+	return 1;
+}
+
+static int audit_match_signal(struct audit_entry *entry)
+{
+	struct audit_field *arch = entry->rule.arch_f;
+
+	if (!arch) {
+		/* When arch is unspecified, we must check both masks on biarch
+		 * as syscall number alone is ambiguous. */
+		return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
+					       entry->rule.mask) &&
+			audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
+					       entry->rule.mask));
+	}
+
+	switch(audit_classify_arch(arch->val)) {
+	case 0: /* native */
+		return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
+					       entry->rule.mask));
+	case 1: /* 32bit on biarch */
+		return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
+					       entry->rule.mask));
+	default:
+		return 1;
+	}
+}
+#endif
+
+/* Common user-space to kernel rule translation. */
+static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule)
+{
+	unsigned listnr;
+	struct audit_entry *entry;
+	int i, err;
+
+	err = -EINVAL;
+	listnr = rule->flags & ~AUDIT_FILTER_PREPEND;
+	switch(listnr) {
+	default:
+		goto exit_err;
+#ifdef CONFIG_AUDITSYSCALL
+	case AUDIT_FILTER_ENTRY:
+		if (rule->action == AUDIT_ALWAYS)
+			goto exit_err;
+	case AUDIT_FILTER_EXIT:
+	case AUDIT_FILTER_TASK:
+#endif
+	case AUDIT_FILTER_USER:
+	case AUDIT_FILTER_TYPE:
+		;
+	}
+	if (unlikely(rule->action == AUDIT_POSSIBLE)) {
+		printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n");
+		goto exit_err;
+	}
+	if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS)
+		goto exit_err;
+	if (rule->field_count > AUDIT_MAX_FIELDS)
+		goto exit_err;
+
+	err = -ENOMEM;
+	entry = audit_init_entry(rule->field_count);
+	if (!entry)
+		goto exit_err;
+
+	entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND;
+	entry->rule.listnr = listnr;
+	entry->rule.action = rule->action;
+	entry->rule.field_count = rule->field_count;
+
+	for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
+		entry->rule.mask[i] = rule->mask[i];
+
+	for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) {
+		int bit = AUDIT_BITMASK_SIZE * 32 - i - 1;
+		__u32 *p = &entry->rule.mask[AUDIT_WORD(bit)];
+		__u32 *class;
+
+		if (!(*p & AUDIT_BIT(bit)))
+			continue;
+		*p &= ~AUDIT_BIT(bit);
+		class = classes[i];
+		if (class) {
+			int j;
+			for (j = 0; j < AUDIT_BITMASK_SIZE; j++)
+				entry->rule.mask[j] |= class[j];
+		}
+	}
+
+	return entry;
+
+exit_err:
+	return ERR_PTR(err);
+}
+
+static u32 audit_ops[] =
+{
+	[Audit_equal] = AUDIT_EQUAL,
+	[Audit_not_equal] = AUDIT_NOT_EQUAL,
+	[Audit_bitmask] = AUDIT_BIT_MASK,
+	[Audit_bittest] = AUDIT_BIT_TEST,
+	[Audit_lt] = AUDIT_LESS_THAN,
+	[Audit_gt] = AUDIT_GREATER_THAN,
+	[Audit_le] = AUDIT_LESS_THAN_OR_EQUAL,
+	[Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL,
+};
+
+static u32 audit_to_op(u32 op)
+{
+	u32 n;
+	for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++)
+		;
+	return n;
+}
+
+
+/* Translate struct audit_rule to kernel's rule respresentation.
+ * Exists for backward compatibility with userspace. */
+static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
+{
+	struct audit_entry *entry;
+	int err = 0;
+	int i;
+
+	entry = audit_to_entry_common(rule);
+	if (IS_ERR(entry))
+		goto exit_nofree;
+
+	for (i = 0; i < rule->field_count; i++) {
+		struct audit_field *f = &entry->rule.fields[i];
+		u32 n;
+
+		n = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS);
+
+		/* Support for legacy operators where
+		 * AUDIT_NEGATE bit signifies != and otherwise assumes == */
+		if (n & AUDIT_NEGATE)
+			f->op = Audit_not_equal;
+		else if (!n)
+			f->op = Audit_equal;
+		else
+			f->op = audit_to_op(n);
+
+		entry->rule.vers_ops = (n & AUDIT_OPERATORS) ? 2 : 1;
+
+		f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS);
+		f->val = rule->values[i];
+
+		err = -EINVAL;
+		if (f->op == Audit_bad)
+			goto exit_free;
+
+		switch(f->type) {
+		default:
+			goto exit_free;
+		case AUDIT_PID:
+		case AUDIT_UID:
+		case AUDIT_EUID:
+		case AUDIT_SUID:
+		case AUDIT_FSUID:
+		case AUDIT_GID:
+		case AUDIT_EGID:
+		case AUDIT_SGID:
+		case AUDIT_FSGID:
+		case AUDIT_LOGINUID:
+		case AUDIT_PERS:
+		case AUDIT_MSGTYPE:
+		case AUDIT_PPID:
+		case AUDIT_DEVMAJOR:
+		case AUDIT_DEVMINOR:
+		case AUDIT_EXIT:
+		case AUDIT_SUCCESS:
+			/* bit ops are only useful on syscall args */
+			if (f->op == Audit_bitmask || f->op == Audit_bittest)
+				goto exit_free;
+			break;
+		case AUDIT_ARG0:
+		case AUDIT_ARG1:
+		case AUDIT_ARG2:
+		case AUDIT_ARG3:
+			break;
+		/* arch is only allowed to be = or != */
+		case AUDIT_ARCH:
+			if (f->op != Audit_not_equal && f->op != Audit_equal)
+				goto exit_free;
+			entry->rule.arch_f = f;
+			break;
+		case AUDIT_PERM:
+			if (f->val & ~15)
+				goto exit_free;
+			break;
+		case AUDIT_FILETYPE:
+			if (f->val & ~S_IFMT)
+				goto exit_free;
+			break;
+		case AUDIT_INODE:
+			err = audit_to_inode(&entry->rule, f);
+			if (err)
+				goto exit_free;
+			break;
+		}
+	}
+
+	if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
+		entry->rule.inode_f = NULL;
+
+exit_nofree:
+	return entry;
+
+exit_free:
+	audit_free_rule(entry);
+	return ERR_PTR(err);
+}
+
+/* Translate struct audit_rule_data to kernel's rule respresentation. */
+static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
+					       size_t datasz)
+{
+	int err = 0;
+	struct audit_entry *entry;
+	void *bufp;
+	size_t remain = datasz - sizeof(struct audit_rule_data);
+	int i;
+	char *str;
+
+	entry = audit_to_entry_common((struct audit_rule *)data);
+	if (IS_ERR(entry))
+		goto exit_nofree;
+
+	bufp = data->buf;
+	entry->rule.vers_ops = 2;
+	for (i = 0; i < data->field_count; i++) {
+		struct audit_field *f = &entry->rule.fields[i];
+
+		err = -EINVAL;
+
+		f->op = audit_to_op(data->fieldflags[i]);
+		if (f->op == Audit_bad)
+			goto exit_free;
+
+		f->type = data->fields[i];
+		f->val = data->values[i];
+		f->lsm_str = NULL;
+		f->lsm_rule = NULL;
+		switch(f->type) {
+		case AUDIT_PID:
+		case AUDIT_UID:
+		case AUDIT_EUID:
+		case AUDIT_SUID:
+		case AUDIT_FSUID:
+		case AUDIT_GID:
+		case AUDIT_EGID:
+		case AUDIT_SGID:
+		case AUDIT_FSGID:
+		case AUDIT_LOGINUID:
+		case AUDIT_PERS:
+		case AUDIT_MSGTYPE:
+		case AUDIT_PPID:
+		case AUDIT_DEVMAJOR:
+		case AUDIT_DEVMINOR:
+		case AUDIT_EXIT:
+		case AUDIT_SUCCESS:
+		case AUDIT_ARG0:
+		case AUDIT_ARG1:
+		case AUDIT_ARG2:
+		case AUDIT_ARG3:
+		case AUDIT_OBJ_UID:
+		case AUDIT_OBJ_GID:
+			break;
+		case AUDIT_ARCH:
+			entry->rule.arch_f = f;
+			break;
+		case AUDIT_SUBJ_USER:
+		case AUDIT_SUBJ_ROLE:
+		case AUDIT_SUBJ_TYPE:
+		case AUDIT_SUBJ_SEN:
+		case AUDIT_SUBJ_CLR:
+		case AUDIT_OBJ_USER:
+		case AUDIT_OBJ_ROLE:
+		case AUDIT_OBJ_TYPE:
+		case AUDIT_OBJ_LEV_LOW:
+		case AUDIT_OBJ_LEV_HIGH:
+			str = audit_unpack_string(&bufp, &remain, f->val);
+			if (IS_ERR(str))
+				goto exit_free;
+			entry->rule.buflen += f->val;
+
+			err = security_audit_rule_init(f->type, f->op, str,
+						       (void **)&f->lsm_rule);
+			/* Keep currently invalid fields around in case they
+			 * become valid after a policy reload. */
+			if (err == -EINVAL) {
+				printk(KERN_WARNING "audit rule for LSM "
+				       "\'%s\' is invalid\n",  str);
+				err = 0;
+			}
+			if (err) {
+				kfree(str);
+				goto exit_free;
+			} else
+				f->lsm_str = str;
+			break;
+		case AUDIT_WATCH:
+			str = audit_unpack_string(&bufp, &remain, f->val);
+			if (IS_ERR(str))
+				goto exit_free;
+			entry->rule.buflen += f->val;
+
+			err = audit_to_watch(&entry->rule, str, f->val, f->op);
+			if (err) {
+				kfree(str);
+				goto exit_free;
+			}
+			break;
+		case AUDIT_DIR:
+			str = audit_unpack_string(&bufp, &remain, f->val);
+			if (IS_ERR(str))
+				goto exit_free;
+			entry->rule.buflen += f->val;
+
+			err = audit_make_tree(&entry->rule, str, f->op);
+			kfree(str);
+			if (err)
+				goto exit_free;
+			break;
+		case AUDIT_INODE:
+			err = audit_to_inode(&entry->rule, f);
+			if (err)
+				goto exit_free;
+			break;
+		case AUDIT_FILTERKEY:
+			if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN)
+				goto exit_free;
+			str = audit_unpack_string(&bufp, &remain, f->val);
+			if (IS_ERR(str))
+				goto exit_free;
+			entry->rule.buflen += f->val;
+			entry->rule.filterkey = str;
+			break;
+		case AUDIT_PERM:
+			if (f->val & ~15)
+				goto exit_free;
+			break;
+		case AUDIT_FILETYPE:
+			if (f->val & ~S_IFMT)
+				goto exit_free;
+			break;
+		case AUDIT_FIELD_COMPARE:
+			if (f->val > AUDIT_MAX_FIELD_COMPARE)
+				goto exit_free;
+			break;
+		default:
+			goto exit_free;
+		}
+	}
+
+	if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
+		entry->rule.inode_f = NULL;
+
+exit_nofree:
+	return entry;
+
+exit_free:
+	audit_free_rule(entry);
+	return ERR_PTR(err);
+}
+
+/* Pack a filter field's string representation into data block. */
+static inline size_t audit_pack_string(void **bufp, const char *str)
+{
+	size_t len = strlen(str);
+
+	memcpy(*bufp, str, len);
+	*bufp += len;
+
+	return len;
+}
+
+/* Translate kernel rule respresentation to struct audit_rule.
+ * Exists for backward compatibility with userspace. */
+static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule)
+{
+	struct audit_rule *rule;
+	int i;
+
+	rule = kzalloc(sizeof(*rule), GFP_KERNEL);
+	if (unlikely(!rule))
+		return NULL;
+
+	rule->flags = krule->flags | krule->listnr;
+	rule->action = krule->action;
+	rule->field_count = krule->field_count;
+	for (i = 0; i < rule->field_count; i++) {
+		rule->values[i] = krule->fields[i].val;
+		rule->fields[i] = krule->fields[i].type;
+
+		if (krule->vers_ops == 1) {
+			if (krule->fields[i].op == Audit_not_equal)
+				rule->fields[i] |= AUDIT_NEGATE;
+		} else {
+			rule->fields[i] |= audit_ops[krule->fields[i].op];
+		}
+	}
+	for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i];
+
+	return rule;
+}
+
+/* Translate kernel rule respresentation to struct audit_rule_data. */
+static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
+{
+	struct audit_rule_data *data;
+	void *bufp;
+	int i;
+
+	data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL);
+	if (unlikely(!data))
+		return NULL;
+	memset(data, 0, sizeof(*data));
+
+	data->flags = krule->flags | krule->listnr;
+	data->action = krule->action;
+	data->field_count = krule->field_count;
+	bufp = data->buf;
+	for (i = 0; i < data->field_count; i++) {
+		struct audit_field *f = &krule->fields[i];
+
+		data->fields[i] = f->type;
+		data->fieldflags[i] = audit_ops[f->op];
+		switch(f->type) {
+		case AUDIT_SUBJ_USER:
+		case AUDIT_SUBJ_ROLE:
+		case AUDIT_SUBJ_TYPE:
+		case AUDIT_SUBJ_SEN:
+		case AUDIT_SUBJ_CLR:
+		case AUDIT_OBJ_USER:
+		case AUDIT_OBJ_ROLE:
+		case AUDIT_OBJ_TYPE:
+		case AUDIT_OBJ_LEV_LOW:
+		case AUDIT_OBJ_LEV_HIGH:
+			data->buflen += data->values[i] =
+				audit_pack_string(&bufp, f->lsm_str);
+			break;
+		case AUDIT_WATCH:
+			data->buflen += data->values[i] =
+				audit_pack_string(&bufp,
+						  audit_watch_path(krule->watch));
+			break;
+		case AUDIT_DIR:
+			data->buflen += data->values[i] =
+				audit_pack_string(&bufp,
+						  audit_tree_path(krule->tree));
+			break;
+		case AUDIT_FILTERKEY:
+			data->buflen += data->values[i] =
+				audit_pack_string(&bufp, krule->filterkey);
+			break;
+		default:
+			data->values[i] = f->val;
+		}
+	}
+	for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i];
+
+	return data;
+}
+
+/* Compare two rules in kernel format.  Considered success if rules
+ * don't match. */
+static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b)
+{
+	int i;
+
+	if (a->flags != b->flags ||
+	    a->listnr != b->listnr ||
+	    a->action != b->action ||
+	    a->field_count != b->field_count)
+		return 1;
+
+	for (i = 0; i < a->field_count; i++) {
+		if (a->fields[i].type != b->fields[i].type ||
+		    a->fields[i].op != b->fields[i].op)
+			return 1;
+
+		switch(a->fields[i].type) {
+		case AUDIT_SUBJ_USER:
+		case AUDIT_SUBJ_ROLE:
+		case AUDIT_SUBJ_TYPE:
+		case AUDIT_SUBJ_SEN:
+		case AUDIT_SUBJ_CLR:
+		case AUDIT_OBJ_USER:
+		case AUDIT_OBJ_ROLE:
+		case AUDIT_OBJ_TYPE:
+		case AUDIT_OBJ_LEV_LOW:
+		case AUDIT_OBJ_LEV_HIGH:
+			if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str))
+				return 1;
+			break;
+		case AUDIT_WATCH:
+			if (strcmp(audit_watch_path(a->watch),
+				   audit_watch_path(b->watch)))
+				return 1;
+			break;
+		case AUDIT_DIR:
+			if (strcmp(audit_tree_path(a->tree),
+				   audit_tree_path(b->tree)))
+				return 1;
+			break;
+		case AUDIT_FILTERKEY:
+			/* both filterkeys exist based on above type compare */
+			if (strcmp(a->filterkey, b->filterkey))
+				return 1;
+			break;
+		default:
+			if (a->fields[i].val != b->fields[i].val)
+				return 1;
+		}
+	}
+
+	for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
+		if (a->mask[i] != b->mask[i])
+			return 1;
+
+	return 0;
+}
+
+/* Duplicate LSM field information.  The lsm_rule is opaque, so must be
+ * re-initialized. */
+static inline int audit_dupe_lsm_field(struct audit_field *df,
+					   struct audit_field *sf)
+{
+	int ret = 0;
+	char *lsm_str;
+
+	/* our own copy of lsm_str */
+	lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL);
+	if (unlikely(!lsm_str))
+		return -ENOMEM;
+	df->lsm_str = lsm_str;
+
+	/* our own (refreshed) copy of lsm_rule */
+	ret = security_audit_rule_init(df->type, df->op, df->lsm_str,
+				       (void **)&df->lsm_rule);
+	/* Keep currently invalid fields around in case they
+	 * become valid after a policy reload. */
+	if (ret == -EINVAL) {
+		printk(KERN_WARNING "audit rule for LSM \'%s\' is "
+		       "invalid\n", df->lsm_str);
+		ret = 0;
+	}
+
+	return ret;
+}
+
+/* Duplicate an audit rule.  This will be a deep copy with the exception
+ * of the watch - that pointer is carried over.  The LSM specific fields
+ * will be updated in the copy.  The point is to be able to replace the old
+ * rule with the new rule in the filterlist, then free the old rule.
+ * The rlist element is undefined; list manipulations are handled apart from
+ * the initial copy. */
+struct audit_entry *audit_dupe_rule(struct audit_krule *old)
+{
+	u32 fcount = old->field_count;
+	struct audit_entry *entry;
+	struct audit_krule *new;
+	char *fk;
+	int i, err = 0;
+
+	entry = audit_init_entry(fcount);
+	if (unlikely(!entry))
+		return ERR_PTR(-ENOMEM);
+
+	new = &entry->rule;
+	new->vers_ops = old->vers_ops;
+	new->flags = old->flags;
+	new->listnr = old->listnr;
+	new->action = old->action;
+	for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
+		new->mask[i] = old->mask[i];
+	new->prio = old->prio;
+	new->buflen = old->buflen;
+	new->inode_f = old->inode_f;
+	new->field_count = old->field_count;
+
+	/*
+	 * note that we are OK with not refcounting here; audit_match_tree()
+	 * never dereferences tree and we can't get false positives there
+	 * since we'd have to have rule gone from the list *and* removed
+	 * before the chunks found by lookup had been allocated, i.e. before
+	 * the beginning of list scan.
+	 */
+	new->tree = old->tree;
+	memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount);
+
+	/* deep copy this information, updating the lsm_rule fields, because
+	 * the originals will all be freed when the old rule is freed. */
+	for (i = 0; i < fcount; i++) {
+		switch (new->fields[i].type) {
+		case AUDIT_SUBJ_USER:
+		case AUDIT_SUBJ_ROLE:
+		case AUDIT_SUBJ_TYPE:
+		case AUDIT_SUBJ_SEN:
+		case AUDIT_SUBJ_CLR:
+		case AUDIT_OBJ_USER:
+		case AUDIT_OBJ_ROLE:
+		case AUDIT_OBJ_TYPE:
+		case AUDIT_OBJ_LEV_LOW:
+		case AUDIT_OBJ_LEV_HIGH:
+			err = audit_dupe_lsm_field(&new->fields[i],
+						       &old->fields[i]);
+			break;
+		case AUDIT_FILTERKEY:
+			fk = kstrdup(old->filterkey, GFP_KERNEL);
+			if (unlikely(!fk))
+				err = -ENOMEM;
+			else
+				new->filterkey = fk;
+		}
+		if (err) {
+			audit_free_rule(entry);
+			return ERR_PTR(err);
+		}
+	}
+
+	if (old->watch) {
+		audit_get_watch(old->watch);
+		new->watch = old->watch;
+	}
+
+	return entry;
+}
+
+/* Find an existing audit rule.
+ * Caller must hold audit_filter_mutex to prevent stale rule data. */
+static struct audit_entry *audit_find_rule(struct audit_entry *entry,
+					   struct list_head **p)
+{
+	struct audit_entry *e, *found = NULL;
+	struct list_head *list;
+	int h;
+
+	if (entry->rule.inode_f) {
+		h = audit_hash_ino(entry->rule.inode_f->val);
+		*p = list = &audit_inode_hash[h];
+	} else if (entry->rule.watch) {
+		/* we don't know the inode number, so must walk entire hash */
+		for (h = 0; h < AUDIT_INODE_BUCKETS; h++) {
+			list = &audit_inode_hash[h];
+			list_for_each_entry(e, list, list)
+				if (!audit_compare_rule(&entry->rule, &e->rule)) {
+					found = e;
+					goto out;
+				}
+		}
+		goto out;
+	} else {
+		*p = list = &audit_filter_list[entry->rule.listnr];
+	}
+
+	list_for_each_entry(e, list, list)
+		if (!audit_compare_rule(&entry->rule, &e->rule)) {
+			found = e;
+			goto out;
+		}
+
+out:
+	return found;
+}
+
+static u64 prio_low = ~0ULL/2;
+static u64 prio_high = ~0ULL/2 - 1;
+
+/* Add rule to given filterlist if not a duplicate. */
+static inline int audit_add_rule(struct audit_entry *entry)
+{
+	struct audit_entry *e;
+	struct audit_watch *watch = entry->rule.watch;
+	struct audit_tree *tree = entry->rule.tree;
+	struct list_head *list;
+	int err;
+#ifdef CONFIG_AUDITSYSCALL
+	int dont_count = 0;
+
+	/* If either of these, don't count towards total */
+	if (entry->rule.listnr == AUDIT_FILTER_USER ||
+		entry->rule.listnr == AUDIT_FILTER_TYPE)
+		dont_count = 1;
+#endif
+
+	mutex_lock(&audit_filter_mutex);
+	e = audit_find_rule(entry, &list);
+	if (e) {
+		mutex_unlock(&audit_filter_mutex);
+		err = -EEXIST;
+		/* normally audit_add_tree_rule() will free it on failure */
+		if (tree)
+			audit_put_tree(tree);
+		goto error;
+	}
+
+	if (watch) {
+		/* audit_filter_mutex is dropped and re-taken during this call */
+		err = audit_add_watch(&entry->rule, &list);
+		if (err) {
+			mutex_unlock(&audit_filter_mutex);
+			goto error;
+		}
+	}
+	if (tree) {
+		err = audit_add_tree_rule(&entry->rule);
+		if (err) {
+			mutex_unlock(&audit_filter_mutex);
+			goto error;
+		}
+	}
+
+	entry->rule.prio = ~0ULL;
+	if (entry->rule.listnr == AUDIT_FILTER_EXIT) {
+		if (entry->rule.flags & AUDIT_FILTER_PREPEND)
+			entry->rule.prio = ++prio_high;
+		else
+			entry->rule.prio = --prio_low;
+	}
+
+	if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
+		list_add(&entry->rule.list,
+			 &audit_rules_list[entry->rule.listnr]);
+		list_add_rcu(&entry->list, list);
+		entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
+	} else {
+		list_add_tail(&entry->rule.list,
+			      &audit_rules_list[entry->rule.listnr]);
+		list_add_tail_rcu(&entry->list, list);
+	}
+#ifdef CONFIG_AUDITSYSCALL
+	if (!dont_count)
+		audit_n_rules++;
+
+	if (!audit_match_signal(entry))
+		audit_signals++;
+#endif
+	mutex_unlock(&audit_filter_mutex);
+
+ 	return 0;
+
+error:
+	if (watch)
+		audit_put_watch(watch); /* tmp watch, matches initial get */
+	return err;
+}
+
+/* Remove an existing rule from filterlist. */
+static inline int audit_del_rule(struct audit_entry *entry)
+{
+	struct audit_entry  *e;
+	struct audit_watch *watch = entry->rule.watch;
+	struct audit_tree *tree = entry->rule.tree;
+	struct list_head *list;
+	int ret = 0;
+#ifdef CONFIG_AUDITSYSCALL
+	int dont_count = 0;
+
+	/* If either of these, don't count towards total */
+	if (entry->rule.listnr == AUDIT_FILTER_USER ||
+		entry->rule.listnr == AUDIT_FILTER_TYPE)
+		dont_count = 1;
+#endif
+
+	mutex_lock(&audit_filter_mutex);
+	e = audit_find_rule(entry, &list);
+	if (!e) {
+		mutex_unlock(&audit_filter_mutex);
+		ret = -ENOENT;
+		goto out;
+	}
+
+	if (e->rule.watch)
+		audit_remove_watch_rule(&e->rule);
+
+	if (e->rule.tree)
+		audit_remove_tree_rule(&e->rule);
+
+	list_del_rcu(&e->list);
+	list_del(&e->rule.list);
+	call_rcu(&e->rcu, audit_free_rule_rcu);
+
+#ifdef CONFIG_AUDITSYSCALL
+	if (!dont_count)
+		audit_n_rules--;
+
+	if (!audit_match_signal(entry))
+		audit_signals--;
+#endif
+	mutex_unlock(&audit_filter_mutex);
+
+out:
+	if (watch)
+		audit_put_watch(watch); /* match initial get */
+	if (tree)
+		audit_put_tree(tree);	/* that's the temporary one */
+
+	return ret;
+}
+
+/* List rules using struct audit_rule.  Exists for backward
+ * compatibility with userspace. */
+static void audit_list(int pid, int seq, struct sk_buff_head *q)
+{
+	struct sk_buff *skb;
+	struct audit_krule *r;
+	int i;
+
+	/* This is a blocking read, so use audit_filter_mutex instead of rcu
+	 * iterator to sync with list writers. */
+	for (i=0; i<AUDIT_NR_FILTERS; i++) {
+		list_for_each_entry(r, &audit_rules_list[i], list) {
+			struct audit_rule *rule;
+
+			rule = audit_krule_to_rule(r);
+			if (unlikely(!rule))
+				break;
+			skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1,
+					 rule, sizeof(*rule));
+			if (skb)
+				skb_queue_tail(q, skb);
+			kfree(rule);
+		}
+	}
+	skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0);
+	if (skb)
+		skb_queue_tail(q, skb);
+}
+
+/* List rules using struct audit_rule_data. */
+static void audit_list_rules(int pid, int seq, struct sk_buff_head *q)
+{
+	struct sk_buff *skb;
+	struct audit_krule *r;
+	int i;
+
+	/* This is a blocking read, so use audit_filter_mutex instead of rcu
+	 * iterator to sync with list writers. */
+	for (i=0; i<AUDIT_NR_FILTERS; i++) {
+		list_for_each_entry(r, &audit_rules_list[i], list) {
+			struct audit_rule_data *data;
+
+			data = audit_krule_to_data(r);
+			if (unlikely(!data))
+				break;
+			skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1,
+					 data, sizeof(*data) + data->buflen);
+			if (skb)
+				skb_queue_tail(q, skb);
+			kfree(data);
+		}
+	}
+	skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
+	if (skb)
+		skb_queue_tail(q, skb);
+}
+
+/* Log rule additions and removals */
+static void audit_log_rule_change(uid_t loginuid, u32 sessionid, u32 sid,
+				  char *action, struct audit_krule *rule,
+				  int res)
+{
+	struct audit_buffer *ab;
+
+	if (!audit_enabled)
+		return;
+
+	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+	if (!ab)
+		return;
+	audit_log_format(ab, "auid=%u ses=%u", loginuid, sessionid);
+	if (sid) {
+		char *ctx = NULL;
+		u32 len;
+		if (security_secid_to_secctx(sid, &ctx, &len))
+			audit_log_format(ab, " ssid=%u", sid);
+		else {
+			audit_log_format(ab, " subj=%s", ctx);
+			security_release_secctx(ctx, len);
+		}
+	}
+	audit_log_format(ab, " op=");
+	audit_log_string(ab, action);
+	audit_log_key(ab, rule->filterkey);
+	audit_log_format(ab, " list=%d res=%d", rule->listnr, res);
+	audit_log_end(ab);
+}
+
+/**
+ * audit_receive_filter - apply all rules to the specified message type
+ * @type: audit message type
+ * @pid: target pid for netlink audit messages
+ * @uid: target uid for netlink audit messages
+ * @seq: netlink audit message sequence (serial) number
+ * @data: payload data
+ * @datasz: size of payload data
+ * @loginuid: loginuid of sender
+ * @sessionid: sessionid for netlink audit message
+ * @sid: SE Linux Security ID of sender
+ */
+int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
+			 size_t datasz, uid_t loginuid, u32 sessionid, u32 sid)
+{
+	struct task_struct *tsk;
+	struct audit_netlink_list *dest;
+	int err = 0;
+	struct audit_entry *entry;
+
+	switch (type) {
+	case AUDIT_LIST:
+	case AUDIT_LIST_RULES:
+		/* We can't just spew out the rules here because we might fill
+		 * the available socket buffer space and deadlock waiting for
+		 * auditctl to read from it... which isn't ever going to
+		 * happen if we're actually running in the context of auditctl
+		 * trying to _send_ the stuff */
+
+		dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL);
+		if (!dest)
+			return -ENOMEM;
+		dest->pid = pid;
+		skb_queue_head_init(&dest->q);
+
+		mutex_lock(&audit_filter_mutex);
+		if (type == AUDIT_LIST)
+			audit_list(pid, seq, &dest->q);
+		else
+			audit_list_rules(pid, seq, &dest->q);
+		mutex_unlock(&audit_filter_mutex);
+
+		tsk = kthread_run(audit_send_list, dest, "audit_send_list");
+		if (IS_ERR(tsk)) {
+			skb_queue_purge(&dest->q);
+			kfree(dest);
+			err = PTR_ERR(tsk);
+		}
+		break;
+	case AUDIT_ADD:
+	case AUDIT_ADD_RULE:
+		if (type == AUDIT_ADD)
+			entry = audit_rule_to_entry(data);
+		else
+			entry = audit_data_to_entry(data, datasz);
+		if (IS_ERR(entry))
+			return PTR_ERR(entry);
+
+		err = audit_add_rule(entry);
+		audit_log_rule_change(loginuid, sessionid, sid, "add rule",
+				      &entry->rule, !err);
+
+		if (err)
+			audit_free_rule(entry);
+		break;
+	case AUDIT_DEL:
+	case AUDIT_DEL_RULE:
+		if (type == AUDIT_DEL)
+			entry = audit_rule_to_entry(data);
+		else
+			entry = audit_data_to_entry(data, datasz);
+		if (IS_ERR(entry))
+			return PTR_ERR(entry);
+
+		err = audit_del_rule(entry);
+		audit_log_rule_change(loginuid, sessionid, sid, "remove rule",
+				      &entry->rule, !err);
+
+		audit_free_rule(entry);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return err;
+}
+
+int audit_comparator(u32 left, u32 op, u32 right)
+{
+	switch (op) {
+	case Audit_equal:
+		return (left == right);
+	case Audit_not_equal:
+		return (left != right);
+	case Audit_lt:
+		return (left < right);
+	case Audit_le:
+		return (left <= right);
+	case Audit_gt:
+		return (left > right);
+	case Audit_ge:
+		return (left >= right);
+	case Audit_bitmask:
+		return (left & right);
+	case Audit_bittest:
+		return ((left & right) == right);
+	default:
+		BUG();
+		return 0;
+	}
+}
+
+/* Compare given dentry name with last component in given path,
+ * return of 0 indicates a match. */
+int audit_compare_dname_path(const char *dname, const char *path,
+			     int *dirlen)
+{
+	int dlen, plen;
+	const char *p;
+
+	if (!dname || !path)
+		return 1;
+
+	dlen = strlen(dname);
+	plen = strlen(path);
+	if (plen < dlen)
+		return 1;
+
+	/* disregard trailing slashes */
+	p = path + plen - 1;
+	while ((*p == '/') && (p > path))
+		p--;
+
+	/* find last path component */
+	p = p - dlen + 1;
+	if (p < path)
+		return 1;
+	else if (p > path) {
+		if (*--p != '/')
+			return 1;
+		else
+			p++;
+	}
+
+	/* return length of path's directory component */
+	if (dirlen)
+		*dirlen = p - path;
+	return strncmp(p, dname, dlen);
+}
+
+static int audit_filter_user_rules(struct netlink_skb_parms *cb,
+				   struct audit_krule *rule,
+				   enum audit_state *state)
+{
+	int i;
+
+	for (i = 0; i < rule->field_count; i++) {
+		struct audit_field *f = &rule->fields[i];
+		int result = 0;
+		u32 sid;
+
+		switch (f->type) {
+		case AUDIT_PID:
+			result = audit_comparator(cb->creds.pid, f->op, f->val);
+			break;
+		case AUDIT_UID:
+			result = audit_comparator(cb->creds.uid, f->op, f->val);
+			break;
+		case AUDIT_GID:
+			result = audit_comparator(cb->creds.gid, f->op, f->val);
+			break;
+		case AUDIT_LOGINUID:
+			result = audit_comparator(audit_get_loginuid(current),
+						  f->op, f->val);
+			break;
+		case AUDIT_SUBJ_USER:
+		case AUDIT_SUBJ_ROLE:
+		case AUDIT_SUBJ_TYPE:
+		case AUDIT_SUBJ_SEN:
+		case AUDIT_SUBJ_CLR:
+			if (f->lsm_rule) {
+				security_task_getsecid(current, &sid);
+				result = security_audit_rule_match(sid,
+								   f->type,
+								   f->op,
+								   f->lsm_rule,
+								   NULL);
+			}
+			break;
+		}
+
+		if (!result)
+			return 0;
+	}
+	switch (rule->action) {
+	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
+	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
+	}
+	return 1;
+}
+
+int audit_filter_user(struct netlink_skb_parms *cb)
+{
+	enum audit_state state = AUDIT_DISABLED;
+	struct audit_entry *e;
+	int ret = 1;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) {
+		if (audit_filter_user_rules(cb, &e->rule, &state)) {
+			if (state == AUDIT_DISABLED)
+				ret = 0;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return ret; /* Audit by default */
+}
+
+int audit_filter_type(int type)
+{
+	struct audit_entry *e;
+	int result = 0;
+
+	rcu_read_lock();
+	if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE]))
+		goto unlock_and_return;
+
+	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE],
+				list) {
+		int i;
+		for (i = 0; i < e->rule.field_count; i++) {
+			struct audit_field *f = &e->rule.fields[i];
+			if (f->type == AUDIT_MSGTYPE) {
+				result = audit_comparator(type, f->op, f->val);
+				if (!result)
+					break;
+			}
+		}
+		if (result)
+			goto unlock_and_return;
+	}
+unlock_and_return:
+	rcu_read_unlock();
+	return result;
+}
+
+static int update_lsm_rule(struct audit_krule *r)
+{
+	struct audit_entry *entry = container_of(r, struct audit_entry, rule);
+	struct audit_entry *nentry;
+	int err = 0;
+
+	if (!security_audit_rule_known(r))
+		return 0;
+
+	nentry = audit_dupe_rule(r);
+	if (IS_ERR(nentry)) {
+		/* save the first error encountered for the
+		 * return value */
+		err = PTR_ERR(nentry);
+		audit_panic("error updating LSM filters");
+		if (r->watch)
+			list_del(&r->rlist);
+		list_del_rcu(&entry->list);
+		list_del(&r->list);
+	} else {
+		if (r->watch || r->tree)
+			list_replace_init(&r->rlist, &nentry->rule.rlist);
+		list_replace_rcu(&entry->list, &nentry->list);
+		list_replace(&r->list, &nentry->rule.list);
+	}
+	call_rcu(&entry->rcu, audit_free_rule_rcu);
+
+	return err;
+}
+
+/* This function will re-initialize the lsm_rule field of all applicable rules.
+ * It will traverse the filter lists serarching for rules that contain LSM
+ * specific filter fields.  When such a rule is found, it is copied, the
+ * LSM field is re-initialized, and the old rule is replaced with the
+ * updated rule. */
+int audit_update_lsm_rules(void)
+{
+	struct audit_krule *r, *n;
+	int i, err = 0;
+
+	/* audit_filter_mutex synchronizes the writers */
+	mutex_lock(&audit_filter_mutex);
+
+	for (i = 0; i < AUDIT_NR_FILTERS; i++) {
+		list_for_each_entry_safe(r, n, &audit_rules_list[i], list) {
+			int res = update_lsm_rule(r);
+			if (!err)
+				err = res;
+		}
+	}
+	mutex_unlock(&audit_filter_mutex);
+
+	return err;
+}
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
new file mode 100644
index 00000000000..af1de0f34ea
--- /dev/null
+++ b/kernel/auditsc.c
@@ -0,0 +1,2729 @@
+/* auditsc.c -- System-call auditing support
+ * Handles all system-call specific auditing features.
+ *
+ * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
+ * Copyright 2005 Hewlett-Packard Development Company, L.P.
+ * Copyright (C) 2005, 2006 IBM Corporation
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Written by Rickard E. (Rik) Faith <faith@redhat.com>
+ *
+ * Many of the ideas implemented here are from Stephen C. Tweedie,
+ * especially the idea of avoiding a copy by using getname.
+ *
+ * The method for actual interception of syscall entry and exit (not in
+ * this file -- see entry.S) is based on a GPL'd patch written by
+ * okir@suse.de and Copyright 2003 SuSE Linux AG.
+ *
+ * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
+ * 2006.
+ *
+ * The support of additional filter rules compares (>, <, >=, <=) was
+ * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
+ *
+ * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
+ * filesystem information.
+ *
+ * Subject and object context labeling support added by <danjones@us.ibm.com>
+ * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
+ */
+
+#include <linux/init.h>
+#include <asm/types.h>
+#include <linux/atomic.h>
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/mm.h>
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/mount.h>
+#include <linux/socket.h>
+#include <linux/mqueue.h>
+#include <linux/audit.h>
+#include <linux/personality.h>
+#include <linux/time.h>
+#include <linux/netlink.h>
+#include <linux/compiler.h>
+#include <asm/unistd.h>
+#include <linux/security.h>
+#include <linux/list.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/highmem.h>
+#include <linux/syscalls.h>
+#include <linux/capability.h>
+#include <linux/fs_struct.h>
+
+#include "audit.h"
+
+/* flags stating the success for a syscall */
+#define AUDITSC_INVALID 0
+#define AUDITSC_SUCCESS 1
+#define AUDITSC_FAILURE 2
+
+/* AUDIT_NAMES is the number of slots we reserve in the audit_context
+ * for saving names from getname().  If we get more names we will allocate
+ * a name dynamically and also add those to the list anchored by names_list. */
+#define AUDIT_NAMES	5
+
+/* Indicates that audit should log the full pathname. */
+#define AUDIT_NAME_FULL -1
+
+/* no execve audit message should be longer than this (userspace limits) */
+#define MAX_EXECVE_AUDIT_LEN 7500
+
+/* number of audit rules */
+int audit_n_rules;
+
+/* determines whether we collect data for signals sent */
+int audit_signals;
+
+struct audit_cap_data {
+	kernel_cap_t		permitted;
+	kernel_cap_t		inheritable;
+	union {
+		unsigned int	fE;		/* effective bit of a file capability */
+		kernel_cap_t	effective;	/* effective set of a process */
+	};
+};
+
+/* When fs/namei.c:getname() is called, we store the pointer in name and
+ * we don't let putname() free it (instead we free all of the saved
+ * pointers at syscall exit time).
+ *
+ * Further, in fs/namei.c:path_lookup() we store the inode and device. */
+struct audit_names {
+	struct list_head list;		/* audit_context->names_list */
+	const char	*name;
+	unsigned long	ino;
+	dev_t		dev;
+	umode_t		mode;
+	uid_t		uid;
+	gid_t		gid;
+	dev_t		rdev;
+	u32		osid;
+	struct audit_cap_data fcap;
+	unsigned int	fcap_ver;
+	int		name_len;	/* number of name's characters to log */
+	bool		name_put;	/* call __putname() for this name */
+	/*
+	 * This was an allocated audit_names and not from the array of
+	 * names allocated in the task audit context.  Thus this name
+	 * should be freed on syscall exit
+	 */
+	bool		should_free;
+};
+
+struct audit_aux_data {
+	struct audit_aux_data	*next;
+	int			type;
+};
+
+#define AUDIT_AUX_IPCPERM	0
+
+/* Number of target pids per aux struct. */
+#define AUDIT_AUX_PIDS	16
+
+struct audit_aux_data_execve {
+	struct audit_aux_data	d;
+	int argc;
+	int envc;
+	struct mm_struct *mm;
+};
+
+struct audit_aux_data_pids {
+	struct audit_aux_data	d;
+	pid_t			target_pid[AUDIT_AUX_PIDS];
+	uid_t			target_auid[AUDIT_AUX_PIDS];
+	uid_t			target_uid[AUDIT_AUX_PIDS];
+	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
+	u32			target_sid[AUDIT_AUX_PIDS];
+	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
+	int			pid_count;
+};
+
+struct audit_aux_data_bprm_fcaps {
+	struct audit_aux_data	d;
+	struct audit_cap_data	fcap;
+	unsigned int		fcap_ver;
+	struct audit_cap_data	old_pcap;
+	struct audit_cap_data	new_pcap;
+};
+
+struct audit_aux_data_capset {
+	struct audit_aux_data	d;
+	pid_t			pid;
+	struct audit_cap_data	cap;
+};
+
+struct audit_tree_refs {
+	struct audit_tree_refs *next;
+	struct audit_chunk *c[31];
+};
+
+/* The per-task audit context. */
+struct audit_context {
+	int		    dummy;	/* must be the first element */
+	int		    in_syscall;	/* 1 if task is in a syscall */
+	enum audit_state    state, current_state;
+	unsigned int	    serial;     /* serial number for record */
+	int		    major;      /* syscall number */
+	struct timespec	    ctime;      /* time of syscall entry */
+	unsigned long	    argv[4];    /* syscall arguments */
+	long		    return_code;/* syscall return code */
+	u64		    prio;
+	int		    return_valid; /* return code is valid */
+	/*
+	 * The names_list is the list of all audit_names collected during this
+	 * syscall.  The first AUDIT_NAMES entries in the names_list will
+	 * actually be from the preallocated_names array for performance
+	 * reasons.  Except during allocation they should never be referenced
+	 * through the preallocated_names array and should only be found/used
+	 * by running the names_list.
+	 */
+	struct audit_names  preallocated_names[AUDIT_NAMES];
+	int		    name_count; /* total records in names_list */
+	struct list_head    names_list;	/* anchor for struct audit_names->list */
+	char *		    filterkey;	/* key for rule that triggered record */
+	struct path	    pwd;
+	struct audit_context *previous; /* For nested syscalls */
+	struct audit_aux_data *aux;
+	struct audit_aux_data *aux_pids;
+	struct sockaddr_storage *sockaddr;
+	size_t sockaddr_len;
+				/* Save things to print about task_struct */
+	pid_t		    pid, ppid;
+	uid_t		    uid, euid, suid, fsuid;
+	gid_t		    gid, egid, sgid, fsgid;
+	unsigned long	    personality;
+	int		    arch;
+
+	pid_t		    target_pid;
+	uid_t		    target_auid;
+	uid_t		    target_uid;
+	unsigned int	    target_sessionid;
+	u32		    target_sid;
+	char		    target_comm[TASK_COMM_LEN];
+
+	struct audit_tree_refs *trees, *first_trees;
+	struct list_head killed_trees;
+	int tree_count;
+
+	int type;
+	union {
+		struct {
+			int nargs;
+			long args[6];
+		} socketcall;
+		struct {
+			uid_t			uid;
+			gid_t			gid;
+			umode_t			mode;
+			u32			osid;
+			int			has_perm;
+			uid_t			perm_uid;
+			gid_t			perm_gid;
+			umode_t			perm_mode;
+			unsigned long		qbytes;
+		} ipc;
+		struct {
+			mqd_t			mqdes;
+			struct mq_attr 		mqstat;
+		} mq_getsetattr;
+		struct {
+			mqd_t			mqdes;
+			int			sigev_signo;
+		} mq_notify;
+		struct {
+			mqd_t			mqdes;
+			size_t			msg_len;
+			unsigned int		msg_prio;
+			struct timespec		abs_timeout;
+		} mq_sendrecv;
+		struct {
+			int			oflag;
+			umode_t			mode;
+			struct mq_attr		attr;
+		} mq_open;
+		struct {
+			pid_t			pid;
+			struct audit_cap_data	cap;
+		} capset;
+		struct {
+			int			fd;
+			int			flags;
+		} mmap;
+	};
+	int fds[2];
+
+#if AUDIT_DEBUG
+	int		    put_count;
+	int		    ino_count;
+#endif
+};
+
+static inline int open_arg(int flags, int mask)
+{
+	int n = ACC_MODE(flags);
+	if (flags & (O_TRUNC | O_CREAT))
+		n |= AUDIT_PERM_WRITE;
+	return n & mask;
+}
+
+static int audit_match_perm(struct audit_context *ctx, int mask)
+{
+	unsigned n;
+	if (unlikely(!ctx))
+		return 0;
+	n = ctx->major;
+
+	switch (audit_classify_syscall(ctx->arch, n)) {
+	case 0:	/* native */
+		if ((mask & AUDIT_PERM_WRITE) &&
+		     audit_match_class(AUDIT_CLASS_WRITE, n))
+			return 1;
+		if ((mask & AUDIT_PERM_READ) &&
+		     audit_match_class(AUDIT_CLASS_READ, n))
+			return 1;
+		if ((mask & AUDIT_PERM_ATTR) &&
+		     audit_match_class(AUDIT_CLASS_CHATTR, n))
+			return 1;
+		return 0;
+	case 1: /* 32bit on biarch */
+		if ((mask & AUDIT_PERM_WRITE) &&
+		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
+			return 1;
+		if ((mask & AUDIT_PERM_READ) &&
+		     audit_match_class(AUDIT_CLASS_READ_32, n))
+			return 1;
+		if ((mask & AUDIT_PERM_ATTR) &&
+		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
+			return 1;
+		return 0;
+	case 2: /* open */
+		return mask & ACC_MODE(ctx->argv[1]);
+	case 3: /* openat */
+		return mask & ACC_MODE(ctx->argv[2]);
+	case 4: /* socketcall */
+		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
+	case 5: /* execve */
+		return mask & AUDIT_PERM_EXEC;
+	default:
+		return 0;
+	}
+}
+
+static int audit_match_filetype(struct audit_context *ctx, int val)
+{
+	struct audit_names *n;
+	umode_t mode = (umode_t)val;
+
+	if (unlikely(!ctx))
+		return 0;
+
+	list_for_each_entry(n, &ctx->names_list, list) {
+		if ((n->ino != -1) &&
+		    ((n->mode & S_IFMT) == mode))
+			return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
+ * ->first_trees points to its beginning, ->trees - to the current end of data.
+ * ->tree_count is the number of free entries in array pointed to by ->trees.
+ * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
+ * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
+ * it's going to remain 1-element for almost any setup) until we free context itself.
+ * References in it _are_ dropped - at the same time we free/drop aux stuff.
+ */
+
+#ifdef CONFIG_AUDIT_TREE
+static void audit_set_auditable(struct audit_context *ctx)
+{
+	if (!ctx->prio) {
+		ctx->prio = 1;
+		ctx->current_state = AUDIT_RECORD_CONTEXT;
+	}
+}
+
+static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
+{
+	struct audit_tree_refs *p = ctx->trees;
+	int left = ctx->tree_count;
+	if (likely(left)) {
+		p->c[--left] = chunk;
+		ctx->tree_count = left;
+		return 1;
+	}
+	if (!p)
+		return 0;
+	p = p->next;
+	if (p) {
+		p->c[30] = chunk;
+		ctx->trees = p;
+		ctx->tree_count = 30;
+		return 1;
+	}
+	return 0;
+}
+
+static int grow_tree_refs(struct audit_context *ctx)
+{
+	struct audit_tree_refs *p = ctx->trees;
+	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
+	if (!ctx->trees) {
+		ctx->trees = p;
+		return 0;
+	}
+	if (p)
+		p->next = ctx->trees;
+	else
+		ctx->first_trees = ctx->trees;
+	ctx->tree_count = 31;
+	return 1;
+}
+#endif
+
+static void unroll_tree_refs(struct audit_context *ctx,
+		      struct audit_tree_refs *p, int count)
+{
+#ifdef CONFIG_AUDIT_TREE
+	struct audit_tree_refs *q;
+	int n;
+	if (!p) {
+		/* we started with empty chain */
+		p = ctx->first_trees;
+		count = 31;
+		/* if the very first allocation has failed, nothing to do */
+		if (!p)
+			return;
+	}
+	n = count;
+	for (q = p; q != ctx->trees; q = q->next, n = 31) {
+		while (n--) {
+			audit_put_chunk(q->c[n]);
+			q->c[n] = NULL;
+		}
+	}
+	while (n-- > ctx->tree_count) {
+		audit_put_chunk(q->c[n]);
+		q->c[n] = NULL;
+	}
+	ctx->trees = p;
+	ctx->tree_count = count;
+#endif
+}
+
+static void free_tree_refs(struct audit_context *ctx)
+{
+	struct audit_tree_refs *p, *q;
+	for (p = ctx->first_trees; p; p = q) {
+		q = p->next;
+		kfree(p);
+	}
+}
+
+static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
+{
+#ifdef CONFIG_AUDIT_TREE
+	struct audit_tree_refs *p;
+	int n;
+	if (!tree)
+		return 0;
+	/* full ones */
+	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
+		for (n = 0; n < 31; n++)
+			if (audit_tree_match(p->c[n], tree))
+				return 1;
+	}
+	/* partial */
+	if (p) {
+		for (n = ctx->tree_count; n < 31; n++)
+			if (audit_tree_match(p->c[n], tree))
+				return 1;
+	}
+#endif
+	return 0;
+}
+
+static int audit_compare_id(uid_t uid1,
+			    struct audit_names *name,
+			    unsigned long name_offset,
+			    struct audit_field *f,
+			    struct audit_context *ctx)
+{
+	struct audit_names *n;
+	unsigned long addr;
+	uid_t uid2;
+	int rc;
+
+	BUILD_BUG_ON(sizeof(uid_t) != sizeof(gid_t));
+
+	if (name) {
+		addr = (unsigned long)name;
+		addr += name_offset;
+
+		uid2 = *(uid_t *)addr;
+		rc = audit_comparator(uid1, f->op, uid2);
+		if (rc)
+			return rc;
+	}
+
+	if (ctx) {
+		list_for_each_entry(n, &ctx->names_list, list) {
+			addr = (unsigned long)n;
+			addr += name_offset;
+
+			uid2 = *(uid_t *)addr;
+
+			rc = audit_comparator(uid1, f->op, uid2);
+			if (rc)
+				return rc;
+		}
+	}
+	return 0;
+}
+
+static int audit_field_compare(struct task_struct *tsk,
+			       const struct cred *cred,
+			       struct audit_field *f,
+			       struct audit_context *ctx,
+			       struct audit_names *name)
+{
+	switch (f->val) {
+	/* process to file object comparisons */
+	case AUDIT_COMPARE_UID_TO_OBJ_UID:
+		return audit_compare_id(cred->uid,
+					name, offsetof(struct audit_names, uid),
+					f, ctx);
+	case AUDIT_COMPARE_GID_TO_OBJ_GID:
+		return audit_compare_id(cred->gid,
+					name, offsetof(struct audit_names, gid),
+					f, ctx);
+	case AUDIT_COMPARE_EUID_TO_OBJ_UID:
+		return audit_compare_id(cred->euid,
+					name, offsetof(struct audit_names, uid),
+					f, ctx);
+	case AUDIT_COMPARE_EGID_TO_OBJ_GID:
+		return audit_compare_id(cred->egid,
+					name, offsetof(struct audit_names, gid),
+					f, ctx);
+	case AUDIT_COMPARE_AUID_TO_OBJ_UID:
+		return audit_compare_id(tsk->loginuid,
+					name, offsetof(struct audit_names, uid),
+					f, ctx);
+	case AUDIT_COMPARE_SUID_TO_OBJ_UID:
+		return audit_compare_id(cred->suid,
+					name, offsetof(struct audit_names, uid),
+					f, ctx);
+	case AUDIT_COMPARE_SGID_TO_OBJ_GID:
+		return audit_compare_id(cred->sgid,
+					name, offsetof(struct audit_names, gid),
+					f, ctx);
+	case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
+		return audit_compare_id(cred->fsuid,
+					name, offsetof(struct audit_names, uid),
+					f, ctx);
+	case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
+		return audit_compare_id(cred->fsgid,
+					name, offsetof(struct audit_names, gid),
+					f, ctx);
+	/* uid comparisons */
+	case AUDIT_COMPARE_UID_TO_AUID:
+		return audit_comparator(cred->uid, f->op, tsk->loginuid);
+	case AUDIT_COMPARE_UID_TO_EUID:
+		return audit_comparator(cred->uid, f->op, cred->euid);
+	case AUDIT_COMPARE_UID_TO_SUID:
+		return audit_comparator(cred->uid, f->op, cred->suid);
+	case AUDIT_COMPARE_UID_TO_FSUID:
+		return audit_comparator(cred->uid, f->op, cred->fsuid);
+	/* auid comparisons */
+	case AUDIT_COMPARE_AUID_TO_EUID:
+		return audit_comparator(tsk->loginuid, f->op, cred->euid);
+	case AUDIT_COMPARE_AUID_TO_SUID:
+		return audit_comparator(tsk->loginuid, f->op, cred->suid);
+	case AUDIT_COMPARE_AUID_TO_FSUID:
+		return audit_comparator(tsk->loginuid, f->op, cred->fsuid);
+	/* euid comparisons */
+	case AUDIT_COMPARE_EUID_TO_SUID:
+		return audit_comparator(cred->euid, f->op, cred->suid);
+	case AUDIT_COMPARE_EUID_TO_FSUID:
+		return audit_comparator(cred->euid, f->op, cred->fsuid);
+	/* suid comparisons */
+	case AUDIT_COMPARE_SUID_TO_FSUID:
+		return audit_comparator(cred->suid, f->op, cred->fsuid);
+	/* gid comparisons */
+	case AUDIT_COMPARE_GID_TO_EGID:
+		return audit_comparator(cred->gid, f->op, cred->egid);
+	case AUDIT_COMPARE_GID_TO_SGID:
+		return audit_comparator(cred->gid, f->op, cred->sgid);
+	case AUDIT_COMPARE_GID_TO_FSGID:
+		return audit_comparator(cred->gid, f->op, cred->fsgid);
+	/* egid comparisons */
+	case AUDIT_COMPARE_EGID_TO_SGID:
+		return audit_comparator(cred->egid, f->op, cred->sgid);
+	case AUDIT_COMPARE_EGID_TO_FSGID:
+		return audit_comparator(cred->egid, f->op, cred->fsgid);
+	/* sgid comparison */
+	case AUDIT_COMPARE_SGID_TO_FSGID:
+		return audit_comparator(cred->sgid, f->op, cred->fsgid);
+	default:
+		WARN(1, "Missing AUDIT_COMPARE define.  Report as a bug\n");
+		return 0;
+	}
+	return 0;
+}
+
+/* Determine if any context name data matches a rule's watch data */
+/* Compare a task_struct with an audit_rule.  Return 1 on match, 0
+ * otherwise.
+ *
+ * If task_creation is true, this is an explicit indication that we are
+ * filtering a task rule at task creation time.  This and tsk == current are
+ * the only situations where tsk->cred may be accessed without an rcu read lock.
+ */
+static int audit_filter_rules(struct task_struct *tsk,
+			      struct audit_krule *rule,
+			      struct audit_context *ctx,
+			      struct audit_names *name,
+			      enum audit_state *state,
+			      bool task_creation)
+{
+	const struct cred *cred;
+	int i, need_sid = 1;
+	u32 sid;
+
+	cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
+
+	for (i = 0; i < rule->field_count; i++) {
+		struct audit_field *f = &rule->fields[i];
+		struct audit_names *n;
+		int result = 0;
+
+		switch (f->type) {
+		case AUDIT_PID:
+			result = audit_comparator(tsk->pid, f->op, f->val);
+			break;
+		case AUDIT_PPID:
+			if (ctx) {
+				if (!ctx->ppid)
+					ctx->ppid = sys_getppid();
+				result = audit_comparator(ctx->ppid, f->op, f->val);
+			}
+			break;
+		case AUDIT_UID:
+			result = audit_comparator(cred->uid, f->op, f->val);
+			break;
+		case AUDIT_EUID:
+			result = audit_comparator(cred->euid, f->op, f->val);
+			break;
+		case AUDIT_SUID:
+			result = audit_comparator(cred->suid, f->op, f->val);
+			break;
+		case AUDIT_FSUID:
+			result = audit_comparator(cred->fsuid, f->op, f->val);
+			break;
+		case AUDIT_GID:
+			result = audit_comparator(cred->gid, f->op, f->val);
+			break;
+		case AUDIT_EGID:
+			result = audit_comparator(cred->egid, f->op, f->val);
+			break;
+		case AUDIT_SGID:
+			result = audit_comparator(cred->sgid, f->op, f->val);
+			break;
+		case AUDIT_FSGID:
+			result = audit_comparator(cred->fsgid, f->op, f->val);
+			break;
+		case AUDIT_PERS:
+			result = audit_comparator(tsk->personality, f->op, f->val);
+			break;
+		case AUDIT_ARCH:
+			if (ctx)
+				result = audit_comparator(ctx->arch, f->op, f->val);
+			break;
+
+		case AUDIT_EXIT:
+			if (ctx && ctx->return_valid)
+				result = audit_comparator(ctx->return_code, f->op, f->val);
+			break;
+		case AUDIT_SUCCESS:
+			if (ctx && ctx->return_valid) {
+				if (f->val)
+					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
+				else
+					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
+			}
+			break;
+		case AUDIT_DEVMAJOR:
+			if (name) {
+				if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
+				    audit_comparator(MAJOR(name->rdev), f->op, f->val))
+					++result;
+			} else if (ctx) {
+				list_for_each_entry(n, &ctx->names_list, list) {
+					if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
+					    audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
+						++result;
+						break;
+					}
+				}
+			}
+			break;
+		case AUDIT_DEVMINOR:
+			if (name) {
+				if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
+				    audit_comparator(MINOR(name->rdev), f->op, f->val))
+					++result;
+			} else if (ctx) {
+				list_for_each_entry(n, &ctx->names_list, list) {
+					if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
+					    audit_comparator(MINOR(n->rdev), f->op, f->val)) {
+						++result;
+						break;
+					}
+				}
+			}
+			break;
+		case AUDIT_INODE:
+			if (name)
+				result = (name->ino == f->val);
+			else if (ctx) {
+				list_for_each_entry(n, &ctx->names_list, list) {
+					if (audit_comparator(n->ino, f->op, f->val)) {
+						++result;
+						break;
+					}
+				}
+			}
+			break;
+		case AUDIT_OBJ_UID:
+			if (name) {
+				result = audit_comparator(name->uid, f->op, f->val);
+			} else if (ctx) {
+				list_for_each_entry(n, &ctx->names_list, list) {
+					if (audit_comparator(n->uid, f->op, f->val)) {
+						++result;
+						break;
+					}
+				}
+			}
+			break;
+		case AUDIT_OBJ_GID:
+			if (name) {
+				result = audit_comparator(name->gid, f->op, f->val);
+			} else if (ctx) {
+				list_for_each_entry(n, &ctx->names_list, list) {
+					if (audit_comparator(n->gid, f->op, f->val)) {
+						++result;
+						break;
+					}
+				}
+			}
+			break;
+		case AUDIT_WATCH:
+			if (name)
+				result = audit_watch_compare(rule->watch, name->ino, name->dev);
+			break;
+		case AUDIT_DIR:
+			if (ctx)
+				result = match_tree_refs(ctx, rule->tree);
+			break;
+		case AUDIT_LOGINUID:
+			result = 0;
+			if (ctx)
+				result = audit_comparator(tsk->loginuid, f->op, f->val);
+			break;
+		case AUDIT_SUBJ_USER:
+		case AUDIT_SUBJ_ROLE:
+		case AUDIT_SUBJ_TYPE:
+		case AUDIT_SUBJ_SEN:
+		case AUDIT_SUBJ_CLR:
+			/* NOTE: this may return negative values indicating
+			   a temporary error.  We simply treat this as a
+			   match for now to avoid losing information that
+			   may be wanted.   An error message will also be
+			   logged upon error */
+			if (f->lsm_rule) {
+				if (need_sid) {
+					security_task_getsecid(tsk, &sid);
+					need_sid = 0;
+				}
+				result = security_audit_rule_match(sid, f->type,
+				                                  f->op,
+				                                  f->lsm_rule,
+				                                  ctx);
+			}
+			break;
+		case AUDIT_OBJ_USER:
+		case AUDIT_OBJ_ROLE:
+		case AUDIT_OBJ_TYPE:
+		case AUDIT_OBJ_LEV_LOW:
+		case AUDIT_OBJ_LEV_HIGH:
+			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
+			   also applies here */
+			if (f->lsm_rule) {
+				/* Find files that match */
+				if (name) {
+					result = security_audit_rule_match(
+					           name->osid, f->type, f->op,
+					           f->lsm_rule, ctx);
+				} else if (ctx) {
+					list_for_each_entry(n, &ctx->names_list, list) {
+						if (security_audit_rule_match(n->osid, f->type,
+									      f->op, f->lsm_rule,
+									      ctx)) {
+							++result;
+							break;
+						}
+					}
+				}
+				/* Find ipc objects that match */
+				if (!ctx || ctx->type != AUDIT_IPC)
+					break;
+				if (security_audit_rule_match(ctx->ipc.osid,
+							      f->type, f->op,
+							      f->lsm_rule, ctx))
+					++result;
+			}
+			break;
+		case AUDIT_ARG0:
+		case AUDIT_ARG1:
+		case AUDIT_ARG2:
+		case AUDIT_ARG3:
+			if (ctx)
+				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
+			break;
+		case AUDIT_FILTERKEY:
+			/* ignore this field for filtering */
+			result = 1;
+			break;
+		case AUDIT_PERM:
+			result = audit_match_perm(ctx, f->val);
+			break;
+		case AUDIT_FILETYPE:
+			result = audit_match_filetype(ctx, f->val);
+			break;
+		case AUDIT_FIELD_COMPARE:
+			result = audit_field_compare(tsk, cred, f, ctx, name);
+			break;
+		}
+		if (!result)
+			return 0;
+	}
+
+	if (ctx) {
+		if (rule->prio <= ctx->prio)
+			return 0;
+		if (rule->filterkey) {
+			kfree(ctx->filterkey);
+			ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
+		}
+		ctx->prio = rule->prio;
+	}
+	switch (rule->action) {
+	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
+	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
+	}
+	return 1;
+}
+
+/* At process creation time, we can determine if system-call auditing is
+ * completely disabled for this task.  Since we only have the task
+ * structure at this point, we can only check uid and gid.
+ */
+static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
+{
+	struct audit_entry *e;
+	enum audit_state   state;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
+		if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
+				       &state, true)) {
+			if (state == AUDIT_RECORD_CONTEXT)
+				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
+			rcu_read_unlock();
+			return state;
+		}
+	}
+	rcu_read_unlock();
+	return AUDIT_BUILD_CONTEXT;
+}
+
+/* At syscall entry and exit time, this filter is called if the
+ * audit_state is not low enough that auditing cannot take place, but is
+ * also not high enough that we already know we have to write an audit
+ * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
+ */
+static enum audit_state audit_filter_syscall(struct task_struct *tsk,
+					     struct audit_context *ctx,
+					     struct list_head *list)
+{
+	struct audit_entry *e;
+	enum audit_state state;
+
+	if (audit_pid && tsk->tgid == audit_pid)
+		return AUDIT_DISABLED;
+
+	rcu_read_lock();
+	if (!list_empty(list)) {
+		int word = AUDIT_WORD(ctx->major);
+		int bit  = AUDIT_BIT(ctx->major);
+
+		list_for_each_entry_rcu(e, list, list) {
+			if ((e->rule.mask[word] & bit) == bit &&
+			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
+					       &state, false)) {
+				rcu_read_unlock();
+				ctx->current_state = state;
+				return state;
+			}
+		}
+	}
+	rcu_read_unlock();
+	return AUDIT_BUILD_CONTEXT;
+}
+
+/*
+ * Given an audit_name check the inode hash table to see if they match.
+ * Called holding the rcu read lock to protect the use of audit_inode_hash
+ */
+static int audit_filter_inode_name(struct task_struct *tsk,
+				   struct audit_names *n,
+				   struct audit_context *ctx) {
+	int word, bit;
+	int h = audit_hash_ino((u32)n->ino);
+	struct list_head *list = &audit_inode_hash[h];
+	struct audit_entry *e;
+	enum audit_state state;
+
+	word = AUDIT_WORD(ctx->major);
+	bit  = AUDIT_BIT(ctx->major);
+
+	if (list_empty(list))
+		return 0;
+
+	list_for_each_entry_rcu(e, list, list) {
+		if ((e->rule.mask[word] & bit) == bit &&
+		    audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
+			ctx->current_state = state;
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+/* At syscall exit time, this filter is called if any audit_names have been
+ * collected during syscall processing.  We only check rules in sublists at hash
+ * buckets applicable to the inode numbers in audit_names.
+ * Regarding audit_state, same rules apply as for audit_filter_syscall().
+ */
+void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
+{
+	struct audit_names *n;
+
+	if (audit_pid && tsk->tgid == audit_pid)
+		return;
+
+	rcu_read_lock();
+
+	list_for_each_entry(n, &ctx->names_list, list) {
+		if (audit_filter_inode_name(tsk, n, ctx))
+			break;
+	}
+	rcu_read_unlock();
+}
+
+static inline struct audit_context *audit_get_context(struct task_struct *tsk,
+						      int return_valid,
+						      long return_code)
+{
+	struct audit_context *context = tsk->audit_context;
+
+	if (!context)
+		return NULL;
+	context->return_valid = return_valid;
+
+	/*
+	 * we need to fix up the return code in the audit logs if the actual
+	 * return codes are later going to be fixed up by the arch specific
+	 * signal handlers
+	 *
+	 * This is actually a test for:
+	 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
+	 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
+	 *
+	 * but is faster than a bunch of ||
+	 */
+	if (unlikely(return_code <= -ERESTARTSYS) &&
+	    (return_code >= -ERESTART_RESTARTBLOCK) &&
+	    (return_code != -ENOIOCTLCMD))
+		context->return_code = -EINTR;
+	else
+		context->return_code  = return_code;
+
+	if (context->in_syscall && !context->dummy) {
+		audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
+		audit_filter_inodes(tsk, context);
+	}
+
+	tsk->audit_context = NULL;
+	return context;
+}
+
+static inline void audit_free_names(struct audit_context *context)
+{
+	struct audit_names *n, *next;
+
+#if AUDIT_DEBUG == 2
+	if (context->put_count + context->ino_count != context->name_count) {
+		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
+		       " name_count=%d put_count=%d"
+		       " ino_count=%d [NOT freeing]\n",
+		       __FILE__, __LINE__,
+		       context->serial, context->major, context->in_syscall,
+		       context->name_count, context->put_count,
+		       context->ino_count);
+		list_for_each_entry(n, &context->names_list, list) {
+			printk(KERN_ERR "names[%d] = %p = %s\n", i,
+			       n->name, n->name ?: "(null)");
+		}
+		dump_stack();
+		return;
+	}
+#endif
+#if AUDIT_DEBUG
+	context->put_count  = 0;
+	context->ino_count  = 0;
+#endif
+
+	list_for_each_entry_safe(n, next, &context->names_list, list) {
+		list_del(&n->list);
+		if (n->name && n->name_put)
+			__putname(n->name);
+		if (n->should_free)
+			kfree(n);
+	}
+	context->name_count = 0;
+	path_put(&context->pwd);
+	context->pwd.dentry = NULL;
+	context->pwd.mnt = NULL;
+}
+
+static inline void audit_free_aux(struct audit_context *context)
+{
+	struct audit_aux_data *aux;
+
+	while ((aux = context->aux)) {
+		context->aux = aux->next;
+		kfree(aux);
+	}
+	while ((aux = context->aux_pids)) {
+		context->aux_pids = aux->next;
+		kfree(aux);
+	}
+}
+
+static inline void audit_zero_context(struct audit_context *context,
+				      enum audit_state state)
+{
+	memset(context, 0, sizeof(*context));
+	context->state      = state;
+	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
+}
+
+static inline struct audit_context *audit_alloc_context(enum audit_state state)
+{
+	struct audit_context *context;
+
+	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
+		return NULL;
+	audit_zero_context(context, state);
+	INIT_LIST_HEAD(&context->killed_trees);
+	INIT_LIST_HEAD(&context->names_list);
+	return context;
+}
+
+/**
+ * audit_alloc - allocate an audit context block for a task
+ * @tsk: task
+ *
+ * Filter on the task information and allocate a per-task audit context
+ * if necessary.  Doing so turns on system call auditing for the
+ * specified task.  This is called from copy_process, so no lock is
+ * needed.
+ */
+int audit_alloc(struct task_struct *tsk)
+{
+	struct audit_context *context;
+	enum audit_state     state;
+	char *key = NULL;
+
+	if (likely(!audit_ever_enabled))
+		return 0; /* Return if not auditing. */
+
+	state = audit_filter_task(tsk, &key);
+	if (state == AUDIT_DISABLED)
+		return 0;
+
+	if (!(context = audit_alloc_context(state))) {
+		kfree(key);
+		audit_log_lost("out of memory in audit_alloc");
+		return -ENOMEM;
+	}
+	context->filterkey = key;
+
+	tsk->audit_context  = context;
+	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
+	return 0;
+}
+
+static inline void audit_free_context(struct audit_context *context)
+{
+	struct audit_context *previous;
+	int		     count = 0;
+
+	do {
+		previous = context->previous;
+		if (previous || (count &&  count < 10)) {
+			++count;
+			printk(KERN_ERR "audit(:%d): major=%d name_count=%d:"
+			       " freeing multiple contexts (%d)\n",
+			       context->serial, context->major,
+			       context->name_count, count);
+		}
+		audit_free_names(context);
+		unroll_tree_refs(context, NULL, 0);
+		free_tree_refs(context);
+		audit_free_aux(context);
+		kfree(context->filterkey);
+		kfree(context->sockaddr);
+		kfree(context);
+		context  = previous;
+	} while (context);
+	if (count >= 10)
+		printk(KERN_ERR "audit: freed %d contexts\n", count);
+}
+
+void audit_log_task_context(struct audit_buffer *ab)
+{
+	char *ctx = NULL;
+	unsigned len;
+	int error;
+	u32 sid;
+
+	security_task_getsecid(current, &sid);
+	if (!sid)
+		return;
+
+	error = security_secid_to_secctx(sid, &ctx, &len);
+	if (error) {
+		if (error != -EINVAL)
+			goto error_path;
+		return;
+	}
+
+	audit_log_format(ab, " subj=%s", ctx);
+	security_release_secctx(ctx, len);
+	return;
+
+error_path:
+	audit_panic("error in audit_log_task_context");
+	return;
+}
+
+EXPORT_SYMBOL(audit_log_task_context);
+
+static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
+{
+	char name[sizeof(tsk->comm)];
+	struct mm_struct *mm = tsk->mm;
+	struct vm_area_struct *vma;
+
+	/* tsk == current */
+
+	get_task_comm(name, tsk);
+	audit_log_format(ab, " comm=");
+	audit_log_untrustedstring(ab, name);
+
+	if (mm) {
+		down_read(&mm->mmap_sem);
+		vma = mm->mmap;
+		while (vma) {
+			if ((vma->vm_flags & VM_EXECUTABLE) &&
+			    vma->vm_file) {
+				audit_log_d_path(ab, " exe=",
+						 &vma->vm_file->f_path);
+				break;
+			}
+			vma = vma->vm_next;
+		}
+		up_read(&mm->mmap_sem);
+	}
+	audit_log_task_context(ab);
+}
+
+static int audit_log_pid_context(struct audit_context *context, pid_t pid,
+				 uid_t auid, uid_t uid, unsigned int sessionid,
+				 u32 sid, char *comm)
+{
+	struct audit_buffer *ab;
+	char *ctx = NULL;
+	u32 len;
+	int rc = 0;
+
+	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
+	if (!ab)
+		return rc;
+
+	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
+			 uid, sessionid);
+	if (security_secid_to_secctx(sid, &ctx, &len)) {
+		audit_log_format(ab, " obj=(none)");
+		rc = 1;
+	} else {
+		audit_log_format(ab, " obj=%s", ctx);
+		security_release_secctx(ctx, len);
+	}
+	audit_log_format(ab, " ocomm=");
+	audit_log_untrustedstring(ab, comm);
+	audit_log_end(ab);
+
+	return rc;
+}
+
+/*
+ * to_send and len_sent accounting are very loose estimates.  We aren't
+ * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
+ * within about 500 bytes (next page boundary)
+ *
+ * why snprintf?  an int is up to 12 digits long.  if we just assumed when
+ * logging that a[%d]= was going to be 16 characters long we would be wasting
+ * space in every audit message.  In one 7500 byte message we can log up to
+ * about 1000 min size arguments.  That comes down to about 50% waste of space
+ * if we didn't do the snprintf to find out how long arg_num_len was.
+ */
+static int audit_log_single_execve_arg(struct audit_context *context,
+					struct audit_buffer **ab,
+					int arg_num,
+					size_t *len_sent,
+					const char __user *p,
+					char *buf)
+{
+	char arg_num_len_buf[12];
+	const char __user *tmp_p = p;
+	/* how many digits are in arg_num? 5 is the length of ' a=""' */
+	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
+	size_t len, len_left, to_send;
+	size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
+	unsigned int i, has_cntl = 0, too_long = 0;
+	int ret;
+
+	/* strnlen_user includes the null we don't want to send */
+	len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
+
+	/*
+	 * We just created this mm, if we can't find the strings
+	 * we just copied into it something is _very_ wrong. Similar
+	 * for strings that are too long, we should not have created
+	 * any.
+	 */
+	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
+		WARN_ON(1);
+		send_sig(SIGKILL, current, 0);
+		return -1;
+	}
+
+	/* walk the whole argument looking for non-ascii chars */
+	do {
+		if (len_left > MAX_EXECVE_AUDIT_LEN)
+			to_send = MAX_EXECVE_AUDIT_LEN;
+		else
+			to_send = len_left;
+		ret = copy_from_user(buf, tmp_p, to_send);
+		/*
+		 * There is no reason for this copy to be short. We just
+		 * copied them here, and the mm hasn't been exposed to user-
+		 * space yet.
+		 */
+		if (ret) {
+			WARN_ON(1);
+			send_sig(SIGKILL, current, 0);
+			return -1;
+		}
+		buf[to_send] = '\0';
+		has_cntl = audit_string_contains_control(buf, to_send);
+		if (has_cntl) {
+			/*
+			 * hex messages get logged as 2 bytes, so we can only
+			 * send half as much in each message
+			 */
+			max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
+			break;
+		}
+		len_left -= to_send;
+		tmp_p += to_send;
+	} while (len_left > 0);
+
+	len_left = len;
+
+	if (len > max_execve_audit_len)
+		too_long = 1;
+
+	/* rewalk the argument actually logging the message */
+	for (i = 0; len_left > 0; i++) {
+		int room_left;
+
+		if (len_left > max_execve_audit_len)
+			to_send = max_execve_audit_len;
+		else
+			to_send = len_left;
+
+		/* do we have space left to send this argument in this ab? */
+		room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
+		if (has_cntl)
+			room_left -= (to_send * 2);
+		else
+			room_left -= to_send;
+		if (room_left < 0) {
+			*len_sent = 0;
+			audit_log_end(*ab);
+			*ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
+			if (!*ab)
+				return 0;
+		}
+
+		/*
+		 * first record needs to say how long the original string was
+		 * so we can be sure nothing was lost.
+		 */
+		if ((i == 0) && (too_long))
+			audit_log_format(*ab, " a%d_len=%zu", arg_num,
+					 has_cntl ? 2*len : len);
+
+		/*
+		 * normally arguments are small enough to fit and we already
+		 * filled buf above when we checked for control characters
+		 * so don't bother with another copy_from_user
+		 */
+		if (len >= max_execve_audit_len)
+			ret = copy_from_user(buf, p, to_send);
+		else
+			ret = 0;
+		if (ret) {
+			WARN_ON(1);
+			send_sig(SIGKILL, current, 0);
+			return -1;
+		}
+		buf[to_send] = '\0';
+
+		/* actually log it */
+		audit_log_format(*ab, " a%d", arg_num);
+		if (too_long)
+			audit_log_format(*ab, "[%d]", i);
+		audit_log_format(*ab, "=");
+		if (has_cntl)
+			audit_log_n_hex(*ab, buf, to_send);
+		else
+			audit_log_string(*ab, buf);
+
+		p += to_send;
+		len_left -= to_send;
+		*len_sent += arg_num_len;
+		if (has_cntl)
+			*len_sent += to_send * 2;
+		else
+			*len_sent += to_send;
+	}
+	/* include the null we didn't log */
+	return len + 1;
+}
+
+static void audit_log_execve_info(struct audit_context *context,
+				  struct audit_buffer **ab,
+				  struct audit_aux_data_execve *axi)
+{
+	int i, len;
+	size_t len_sent = 0;
+	const char __user *p;
+	char *buf;
+
+	if (axi->mm != current->mm)
+		return; /* execve failed, no additional info */
+
+	p = (const char __user *)axi->mm->arg_start;
+
+	audit_log_format(*ab, "argc=%d", axi->argc);
+
+	/*
+	 * we need some kernel buffer to hold the userspace args.  Just
+	 * allocate one big one rather than allocating one of the right size
+	 * for every single argument inside audit_log_single_execve_arg()
+	 * should be <8k allocation so should be pretty safe.
+	 */
+	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
+	if (!buf) {
+		audit_panic("out of memory for argv string\n");
+		return;
+	}
+
+	for (i = 0; i < axi->argc; i++) {
+		len = audit_log_single_execve_arg(context, ab, i,
+						  &len_sent, p, buf);
+		if (len <= 0)
+			break;
+		p += len;
+	}
+	kfree(buf);
+}
+
+static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
+{
+	int i;
+
+	audit_log_format(ab, " %s=", prefix);
+	CAP_FOR_EACH_U32(i) {
+		audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
+	}
+}
+
+static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
+{
+	kernel_cap_t *perm = &name->fcap.permitted;
+	kernel_cap_t *inh = &name->fcap.inheritable;
+	int log = 0;
+
+	if (!cap_isclear(*perm)) {
+		audit_log_cap(ab, "cap_fp", perm);
+		log = 1;
+	}
+	if (!cap_isclear(*inh)) {
+		audit_log_cap(ab, "cap_fi", inh);
+		log = 1;
+	}
+
+	if (log)
+		audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver);
+}
+
+static void show_special(struct audit_context *context, int *call_panic)
+{
+	struct audit_buffer *ab;
+	int i;
+
+	ab = audit_log_start(context, GFP_KERNEL, context->type);
+	if (!ab)
+		return;
+
+	switch (context->type) {
+	case AUDIT_SOCKETCALL: {
+		int nargs = context->socketcall.nargs;
+		audit_log_format(ab, "nargs=%d", nargs);
+		for (i = 0; i < nargs; i++)
+			audit_log_format(ab, " a%d=%lx", i,
+				context->socketcall.args[i]);
+		break; }
+	case AUDIT_IPC: {
+		u32 osid = context->ipc.osid;
+
+		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
+			 context->ipc.uid, context->ipc.gid, context->ipc.mode);
+		if (osid) {
+			char *ctx = NULL;
+			u32 len;
+			if (security_secid_to_secctx(osid, &ctx, &len)) {
+				audit_log_format(ab, " osid=%u", osid);
+				*call_panic = 1;
+			} else {
+				audit_log_format(ab, " obj=%s", ctx);
+				security_release_secctx(ctx, len);
+			}
+		}
+		if (context->ipc.has_perm) {
+			audit_log_end(ab);
+			ab = audit_log_start(context, GFP_KERNEL,
+					     AUDIT_IPC_SET_PERM);
+			audit_log_format(ab,
+				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
+				context->ipc.qbytes,
+				context->ipc.perm_uid,
+				context->ipc.perm_gid,
+				context->ipc.perm_mode);
+			if (!ab)
+				return;
+		}
+		break; }
+	case AUDIT_MQ_OPEN: {
+		audit_log_format(ab,
+			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
+			"mq_msgsize=%ld mq_curmsgs=%ld",
+			context->mq_open.oflag, context->mq_open.mode,
+			context->mq_open.attr.mq_flags,
+			context->mq_open.attr.mq_maxmsg,
+			context->mq_open.attr.mq_msgsize,
+			context->mq_open.attr.mq_curmsgs);
+		break; }
+	case AUDIT_MQ_SENDRECV: {
+		audit_log_format(ab,
+			"mqdes=%d msg_len=%zd msg_prio=%u "
+			"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
+			context->mq_sendrecv.mqdes,
+			context->mq_sendrecv.msg_len,
+			context->mq_sendrecv.msg_prio,
+			context->mq_sendrecv.abs_timeout.tv_sec,
+			context->mq_sendrecv.abs_timeout.tv_nsec);
+		break; }
+	case AUDIT_MQ_NOTIFY: {
+		audit_log_format(ab, "mqdes=%d sigev_signo=%d",
+				context->mq_notify.mqdes,
+				context->mq_notify.sigev_signo);
+		break; }
+	case AUDIT_MQ_GETSETATTR: {
+		struct mq_attr *attr = &context->mq_getsetattr.mqstat;
+		audit_log_format(ab,
+			"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
+			"mq_curmsgs=%ld ",
+			context->mq_getsetattr.mqdes,
+			attr->mq_flags, attr->mq_maxmsg,
+			attr->mq_msgsize, attr->mq_curmsgs);
+		break; }
+	case AUDIT_CAPSET: {
+		audit_log_format(ab, "pid=%d", context->capset.pid);
+		audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
+		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
+		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
+		break; }
+	case AUDIT_MMAP: {
+		audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
+				 context->mmap.flags);
+		break; }
+	}
+	audit_log_end(ab);
+}
+
+static void audit_log_name(struct audit_context *context, struct audit_names *n,
+			   int record_num, int *call_panic)
+{
+	struct audit_buffer *ab;
+	ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
+	if (!ab)
+		return; /* audit_panic has been called */
+
+	audit_log_format(ab, "item=%d", record_num);
+
+	if (n->name) {
+		switch (n->name_len) {
+		case AUDIT_NAME_FULL:
+			/* log the full path */
+			audit_log_format(ab, " name=");
+			audit_log_untrustedstring(ab, n->name);
+			break;
+		case 0:
+			/* name was specified as a relative path and the
+			 * directory component is the cwd */
+			audit_log_d_path(ab, " name=", &context->pwd);
+			break;
+		default:
+			/* log the name's directory component */
+			audit_log_format(ab, " name=");
+			audit_log_n_untrustedstring(ab, n->name,
+						    n->name_len);
+		}
+	} else
+		audit_log_format(ab, " name=(null)");
+
+	if (n->ino != (unsigned long)-1) {
+		audit_log_format(ab, " inode=%lu"
+				 " dev=%02x:%02x mode=%#ho"
+				 " ouid=%u ogid=%u rdev=%02x:%02x",
+				 n->ino,
+				 MAJOR(n->dev),
+				 MINOR(n->dev),
+				 n->mode,
+				 n->uid,
+				 n->gid,
+				 MAJOR(n->rdev),
+				 MINOR(n->rdev));
+	}
+	if (n->osid != 0) {
+		char *ctx = NULL;
+		u32 len;
+		if (security_secid_to_secctx(
+			n->osid, &ctx, &len)) {
+			audit_log_format(ab, " osid=%u", n->osid);
+			*call_panic = 2;
+		} else {
+			audit_log_format(ab, " obj=%s", ctx);
+			security_release_secctx(ctx, len);
+		}
+	}
+
+	audit_log_fcaps(ab, n);
+
+	audit_log_end(ab);
+}
+
+static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
+{
+	const struct cred *cred;
+	int i, call_panic = 0;
+	struct audit_buffer *ab;
+	struct audit_aux_data *aux;
+	const char *tty;
+	struct audit_names *n;
+
+	/* tsk == current */
+	context->pid = tsk->pid;
+	if (!context->ppid)
+		context->ppid = sys_getppid();
+	cred = current_cred();
+	context->uid   = cred->uid;
+	context->gid   = cred->gid;
+	context->euid  = cred->euid;
+	context->suid  = cred->suid;
+	context->fsuid = cred->fsuid;
+	context->egid  = cred->egid;
+	context->sgid  = cred->sgid;
+	context->fsgid = cred->fsgid;
+	context->personality = tsk->personality;
+
+	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
+	if (!ab)
+		return;		/* audit_panic has been called */
+	audit_log_format(ab, "arch=%x syscall=%d",
+			 context->arch, context->major);
+	if (context->personality != PER_LINUX)
+		audit_log_format(ab, " per=%lx", context->personality);
+	if (context->return_valid)
+		audit_log_format(ab, " success=%s exit=%ld",
+				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
+				 context->return_code);
+
+	spin_lock_irq(&tsk->sighand->siglock);
+	if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name)
+		tty = tsk->signal->tty->name;
+	else
+		tty = "(none)";
+	spin_unlock_irq(&tsk->sighand->siglock);
+
+	audit_log_format(ab,
+		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
+		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"
+		  " euid=%u suid=%u fsuid=%u"
+		  " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
+		  context->argv[0],
+		  context->argv[1],
+		  context->argv[2],
+		  context->argv[3],
+		  context->name_count,
+		  context->ppid,
+		  context->pid,
+		  tsk->loginuid,
+		  context->uid,
+		  context->gid,
+		  context->euid, context->suid, context->fsuid,
+		  context->egid, context->sgid, context->fsgid, tty,
+		  tsk->sessionid);
+
+
+	audit_log_task_info(ab, tsk);
+	audit_log_key(ab, context->filterkey);
+	audit_log_end(ab);
+
+	for (aux = context->aux; aux; aux = aux->next) {
+
+		ab = audit_log_start(context, GFP_KERNEL, aux->type);
+		if (!ab)
+			continue; /* audit_panic has been called */
+
+		switch (aux->type) {
+
+		case AUDIT_EXECVE: {
+			struct audit_aux_data_execve *axi = (void *)aux;
+			audit_log_execve_info(context, &ab, axi);
+			break; }
+
+		case AUDIT_BPRM_FCAPS: {
+			struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
+			audit_log_format(ab, "fver=%x", axs->fcap_ver);
+			audit_log_cap(ab, "fp", &axs->fcap.permitted);
+			audit_log_cap(ab, "fi", &axs->fcap.inheritable);
+			audit_log_format(ab, " fe=%d", axs->fcap.fE);
+			audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
+			audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
+			audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
+			audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
+			audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
+			audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
+			break; }
+
+		}
+		audit_log_end(ab);
+	}
+
+	if (context->type)
+		show_special(context, &call_panic);
+
+	if (context->fds[0] >= 0) {
+		ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
+		if (ab) {
+			audit_log_format(ab, "fd0=%d fd1=%d",
+					context->fds[0], context->fds[1]);
+			audit_log_end(ab);
+		}
+	}
+
+	if (context->sockaddr_len) {
+		ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
+		if (ab) {
+			audit_log_format(ab, "saddr=");
+			audit_log_n_hex(ab, (void *)context->sockaddr,
+					context->sockaddr_len);
+			audit_log_end(ab);
+		}
+	}
+
+	for (aux = context->aux_pids; aux; aux = aux->next) {
+		struct audit_aux_data_pids *axs = (void *)aux;
+
+		for (i = 0; i < axs->pid_count; i++)
+			if (audit_log_pid_context(context, axs->target_pid[i],
+						  axs->target_auid[i],
+						  axs->target_uid[i],
+						  axs->target_sessionid[i],
+						  axs->target_sid[i],
+						  axs->target_comm[i]))
+				call_panic = 1;
+	}
+
+	if (context->target_pid &&
+	    audit_log_pid_context(context, context->target_pid,
+				  context->target_auid, context->target_uid,
+				  context->target_sessionid,
+				  context->target_sid, context->target_comm))
+			call_panic = 1;
+
+	if (context->pwd.dentry && context->pwd.mnt) {
+		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
+		if (ab) {
+			audit_log_d_path(ab, " cwd=", &context->pwd);
+			audit_log_end(ab);
+		}
+	}
+
+	i = 0;
+	list_for_each_entry(n, &context->names_list, list)
+		audit_log_name(context, n, i++, &call_panic);
+
+	/* Send end of event record to help user space know we are finished */
+	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
+	if (ab)
+		audit_log_end(ab);
+	if (call_panic)
+		audit_panic("error converting sid to string");
+}
+
+/**
+ * audit_free - free a per-task audit context
+ * @tsk: task whose audit context block to free
+ *
+ * Called from copy_process and do_exit
+ */
+void __audit_free(struct task_struct *tsk)
+{
+	struct audit_context *context;
+
+	context = audit_get_context(tsk, 0, 0);
+	if (!context)
+		return;
+
+	/* Check for system calls that do not go through the exit
+	 * function (e.g., exit_group), then free context block.
+	 * We use GFP_ATOMIC here because we might be doing this
+	 * in the context of the idle thread */
+	/* that can happen only if we are called from do_exit() */
+	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
+		audit_log_exit(context, tsk);
+	if (!list_empty(&context->killed_trees))
+		audit_kill_trees(&context->killed_trees);
+
+	audit_free_context(context);
+}
+
+/**
+ * audit_syscall_entry - fill in an audit record at syscall entry
+ * @arch: architecture type
+ * @major: major syscall type (function)
+ * @a1: additional syscall register 1
+ * @a2: additional syscall register 2
+ * @a3: additional syscall register 3
+ * @a4: additional syscall register 4
+ *
+ * Fill in audit context at syscall entry.  This only happens if the
+ * audit context was created when the task was created and the state or
+ * filters demand the audit context be built.  If the state from the
+ * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
+ * then the record will be written at syscall exit time (otherwise, it
+ * will only be written if another part of the kernel requests that it
+ * be written).
+ */
+void __audit_syscall_entry(int arch, int major,
+			 unsigned long a1, unsigned long a2,
+			 unsigned long a3, unsigned long a4)
+{
+	struct task_struct *tsk = current;
+	struct audit_context *context = tsk->audit_context;
+	enum audit_state     state;
+
+	if (!context)
+		return;
+
+	/*
+	 * This happens only on certain architectures that make system
+	 * calls in kernel_thread via the entry.S interface, instead of
+	 * with direct calls.  (If you are porting to a new
+	 * architecture, hitting this condition can indicate that you
+	 * got the _exit/_leave calls backward in entry.S.)
+	 *
+	 * i386     no
+	 * x86_64   no
+	 * ppc64    yes (see arch/powerpc/platforms/iseries/misc.S)
+	 *
+	 * This also happens with vm86 emulation in a non-nested manner
+	 * (entries without exits), so this case must be caught.
+	 */
+	if (context->in_syscall) {
+		struct audit_context *newctx;
+
+#if AUDIT_DEBUG
+		printk(KERN_ERR
+		       "audit(:%d) pid=%d in syscall=%d;"
+		       " entering syscall=%d\n",
+		       context->serial, tsk->pid, context->major, major);
+#endif
+		newctx = audit_alloc_context(context->state);
+		if (newctx) {
+			newctx->previous   = context;
+			context		   = newctx;
+			tsk->audit_context = newctx;
+		} else	{
+			/* If we can't alloc a new context, the best we
+			 * can do is to leak memory (any pending putname
+			 * will be lost).  The only other alternative is
+			 * to abandon auditing. */
+			audit_zero_context(context, context->state);
+		}
+	}
+	BUG_ON(context->in_syscall || context->name_count);
+
+	if (!audit_enabled)
+		return;
+
+	context->arch	    = arch;
+	context->major      = major;
+	context->argv[0]    = a1;
+	context->argv[1]    = a2;
+	context->argv[2]    = a3;
+	context->argv[3]    = a4;
+
+	state = context->state;
+	context->dummy = !audit_n_rules;
+	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
+		context->prio = 0;
+		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
+	}
+	if (state == AUDIT_DISABLED)
+		return;
+
+	context->serial     = 0;
+	context->ctime      = CURRENT_TIME;
+	context->in_syscall = 1;
+	context->current_state  = state;
+	context->ppid       = 0;
+}
+
+/**
+ * audit_syscall_exit - deallocate audit context after a system call
+ * @success: success value of the syscall
+ * @return_code: return value of the syscall
+ *
+ * Tear down after system call.  If the audit context has been marked as
+ * auditable (either because of the AUDIT_RECORD_CONTEXT state from
+ * filtering, or because some other part of the kernel wrote an audit
+ * message), then write out the syscall information.  In call cases,
+ * free the names stored from getname().
+ */
+void __audit_syscall_exit(int success, long return_code)
+{
+	struct task_struct *tsk = current;
+	struct audit_context *context;
+
+	if (success)
+		success = AUDITSC_SUCCESS;
+	else
+		success = AUDITSC_FAILURE;
+
+	context = audit_get_context(tsk, success, return_code);
+	if (!context)
+		return;
+
+	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
+		audit_log_exit(context, tsk);
+
+	context->in_syscall = 0;
+	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
+
+	if (!list_empty(&context->killed_trees))
+		audit_kill_trees(&context->killed_trees);
+
+	if (context->previous) {
+		struct audit_context *new_context = context->previous;
+		context->previous  = NULL;
+		audit_free_context(context);
+		tsk->audit_context = new_context;
+	} else {
+		audit_free_names(context);
+		unroll_tree_refs(context, NULL, 0);
+		audit_free_aux(context);
+		context->aux = NULL;
+		context->aux_pids = NULL;
+		context->target_pid = 0;
+		context->target_sid = 0;
+		context->sockaddr_len = 0;
+		context->type = 0;
+		context->fds[0] = -1;
+		if (context->state != AUDIT_RECORD_CONTEXT) {
+			kfree(context->filterkey);
+			context->filterkey = NULL;
+		}
+		tsk->audit_context = context;
+	}
+}
+
+static inline void handle_one(const struct inode *inode)
+{
+#ifdef CONFIG_AUDIT_TREE
+	struct audit_context *context;
+	struct audit_tree_refs *p;
+	struct audit_chunk *chunk;
+	int count;
+	if (likely(hlist_empty(&inode->i_fsnotify_marks)))
+		return;
+	context = current->audit_context;
+	p = context->trees;
+	count = context->tree_count;
+	rcu_read_lock();
+	chunk = audit_tree_lookup(inode);
+	rcu_read_unlock();
+	if (!chunk)
+		return;
+	if (likely(put_tree_ref(context, chunk)))
+		return;
+	if (unlikely(!grow_tree_refs(context))) {
+		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
+		audit_set_auditable(context);
+		audit_put_chunk(chunk);
+		unroll_tree_refs(context, p, count);
+		return;
+	}
+	put_tree_ref(context, chunk);
+#endif
+}
+
+static void handle_path(const struct dentry *dentry)
+{
+#ifdef CONFIG_AUDIT_TREE
+	struct audit_context *context;
+	struct audit_tree_refs *p;
+	const struct dentry *d, *parent;
+	struct audit_chunk *drop;
+	unsigned long seq;
+	int count;
+
+	context = current->audit_context;
+	p = context->trees;
+	count = context->tree_count;
+retry:
+	drop = NULL;
+	d = dentry;
+	rcu_read_lock();
+	seq = read_seqbegin(&rename_lock);
+	for(;;) {
+		struct inode *inode = d->d_inode;
+		if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
+			struct audit_chunk *chunk;
+			chunk = audit_tree_lookup(inode);
+			if (chunk) {
+				if (unlikely(!put_tree_ref(context, chunk))) {
+					drop = chunk;
+					break;
+				}
+			}
+		}
+		parent = d->d_parent;
+		if (parent == d)
+			break;
+		d = parent;
+	}
+	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
+		rcu_read_unlock();
+		if (!drop) {
+			/* just a race with rename */
+			unroll_tree_refs(context, p, count);
+			goto retry;
+		}
+		audit_put_chunk(drop);
+		if (grow_tree_refs(context)) {
+			/* OK, got more space */
+			unroll_tree_refs(context, p, count);
+			goto retry;
+		}
+		/* too bad */
+		printk(KERN_WARNING
+			"out of memory, audit has lost a tree reference\n");
+		unroll_tree_refs(context, p, count);
+		audit_set_auditable(context);
+		return;
+	}
+	rcu_read_unlock();
+#endif
+}
+
+static struct audit_names *audit_alloc_name(struct audit_context *context)
+{
+	struct audit_names *aname;
+
+	if (context->name_count < AUDIT_NAMES) {
+		aname = &context->preallocated_names[context->name_count];
+		memset(aname, 0, sizeof(*aname));
+	} else {
+		aname = kzalloc(sizeof(*aname), GFP_NOFS);
+		if (!aname)
+			return NULL;
+		aname->should_free = true;
+	}
+
+	aname->ino = (unsigned long)-1;
+	list_add_tail(&aname->list, &context->names_list);
+
+	context->name_count++;
+#if AUDIT_DEBUG
+	context->ino_count++;
+#endif
+	return aname;
+}
+
+/**
+ * audit_getname - add a name to the list
+ * @name: name to add
+ *
+ * Add a name to the list of audit names for this context.
+ * Called from fs/namei.c:getname().
+ */
+void __audit_getname(const char *name)
+{
+	struct audit_context *context = current->audit_context;
+	struct audit_names *n;
+
+	if (!context->in_syscall) {
+#if AUDIT_DEBUG == 2
+		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
+		       __FILE__, __LINE__, context->serial, name);
+		dump_stack();
+#endif
+		return;
+	}
+
+	n = audit_alloc_name(context);
+	if (!n)
+		return;
+
+	n->name = name;
+	n->name_len = AUDIT_NAME_FULL;
+	n->name_put = true;
+
+	if (!context->pwd.dentry)
+		get_fs_pwd(current->fs, &context->pwd);
+}
+
+/* audit_putname - intercept a putname request
+ * @name: name to intercept and delay for putname
+ *
+ * If we have stored the name from getname in the audit context,
+ * then we delay the putname until syscall exit.
+ * Called from include/linux/fs.h:putname().
+ */
+void audit_putname(const char *name)
+{
+	struct audit_context *context = current->audit_context;
+
+	BUG_ON(!context);
+	if (!context->in_syscall) {
+#if AUDIT_DEBUG == 2
+		printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
+		       __FILE__, __LINE__, context->serial, name);
+		if (context->name_count) {
+			struct audit_names *n;
+			int i;
+
+			list_for_each_entry(n, &context->names_list, list)
+				printk(KERN_ERR "name[%d] = %p = %s\n", i,
+				       n->name, n->name ?: "(null)");
+			}
+#endif
+		__putname(name);
+	}
+#if AUDIT_DEBUG
+	else {
+		++context->put_count;
+		if (context->put_count > context->name_count) {
+			printk(KERN_ERR "%s:%d(:%d): major=%d"
+			       " in_syscall=%d putname(%p) name_count=%d"
+			       " put_count=%d\n",
+			       __FILE__, __LINE__,
+			       context->serial, context->major,
+			       context->in_syscall, name, context->name_count,
+			       context->put_count);
+			dump_stack();
+		}
+	}
+#endif
+}
+
+static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry)
+{
+	struct cpu_vfs_cap_data caps;
+	int rc;
+
+	if (!dentry)
+		return 0;
+
+	rc = get_vfs_caps_from_disk(dentry, &caps);
+	if (rc)
+		return rc;
+
+	name->fcap.permitted = caps.permitted;
+	name->fcap.inheritable = caps.inheritable;
+	name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
+	name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
+
+	return 0;
+}
+
+
+/* Copy inode data into an audit_names. */
+static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
+			     const struct inode *inode)
+{
+	name->ino   = inode->i_ino;
+	name->dev   = inode->i_sb->s_dev;
+	name->mode  = inode->i_mode;
+	name->uid   = inode->i_uid;
+	name->gid   = inode->i_gid;
+	name->rdev  = inode->i_rdev;
+	security_inode_getsecid(inode, &name->osid);
+	audit_copy_fcaps(name, dentry);
+}
+
+/**
+ * audit_inode - store the inode and device from a lookup
+ * @name: name being audited
+ * @dentry: dentry being audited
+ *
+ * Called from fs/namei.c:path_lookup().
+ */
+void __audit_inode(const char *name, const struct dentry *dentry)
+{
+	struct audit_context *context = current->audit_context;
+	const struct inode *inode = dentry->d_inode;
+	struct audit_names *n;
+
+	if (!context->in_syscall)
+		return;
+
+	list_for_each_entry_reverse(n, &context->names_list, list) {
+		if (n->name && (n->name == name))
+			goto out;
+	}
+
+	/* unable to find the name from a previous getname() */
+	n = audit_alloc_name(context);
+	if (!n)
+		return;
+out:
+	handle_path(dentry);
+	audit_copy_inode(n, dentry, inode);
+}
+
+/**
+ * audit_inode_child - collect inode info for created/removed objects
+ * @dentry: dentry being audited
+ * @parent: inode of dentry parent
+ *
+ * For syscalls that create or remove filesystem objects, audit_inode
+ * can only collect information for the filesystem object's parent.
+ * This call updates the audit context with the child's information.
+ * Syscalls that create a new filesystem object must be hooked after
+ * the object is created.  Syscalls that remove a filesystem object
+ * must be hooked prior, in order to capture the target inode during
+ * unsuccessful attempts.
+ */
+void __audit_inode_child(const struct dentry *dentry,
+			 const struct inode *parent)
+{
+	struct audit_context *context = current->audit_context;
+	const char *found_parent = NULL, *found_child = NULL;
+	const struct inode *inode = dentry->d_inode;
+	const char *dname = dentry->d_name.name;
+	struct audit_names *n;
+	int dirlen = 0;
+
+	if (!context->in_syscall)
+		return;
+
+	if (inode)
+		handle_one(inode);
+
+	/* parent is more likely, look for it first */
+	list_for_each_entry(n, &context->names_list, list) {
+		if (!n->name)
+			continue;
+
+		if (n->ino == parent->i_ino &&
+		    !audit_compare_dname_path(dname, n->name, &dirlen)) {
+			n->name_len = dirlen; /* update parent data in place */
+			found_parent = n->name;
+			goto add_names;
+		}
+	}
+
+	/* no matching parent, look for matching child */
+	list_for_each_entry(n, &context->names_list, list) {
+		if (!n->name)
+			continue;
+
+		/* strcmp() is the more likely scenario */
+		if (!strcmp(dname, n->name) ||
+		     !audit_compare_dname_path(dname, n->name, &dirlen)) {
+			if (inode)
+				audit_copy_inode(n, NULL, inode);
+			else
+				n->ino = (unsigned long)-1;
+			found_child = n->name;
+			goto add_names;
+		}
+	}
+
+add_names:
+	if (!found_parent) {
+		n = audit_alloc_name(context);
+		if (!n)
+			return;
+		audit_copy_inode(n, NULL, parent);
+	}
+
+	if (!found_child) {
+		n = audit_alloc_name(context);
+		if (!n)
+			return;
+
+		/* Re-use the name belonging to the slot for a matching parent
+		 * directory. All names for this context are relinquished in
+		 * audit_free_names() */
+		if (found_parent) {
+			n->name = found_parent;
+			n->name_len = AUDIT_NAME_FULL;
+			/* don't call __putname() */
+			n->name_put = false;
+		}
+
+		if (inode)
+			audit_copy_inode(n, NULL, inode);
+	}
+}
+EXPORT_SYMBOL_GPL(__audit_inode_child);
+
+/**
+ * auditsc_get_stamp - get local copies of audit_context values
+ * @ctx: audit_context for the task
+ * @t: timespec to store time recorded in the audit_context
+ * @serial: serial value that is recorded in the audit_context
+ *
+ * Also sets the context as auditable.
+ */
+int auditsc_get_stamp(struct audit_context *ctx,
+		       struct timespec *t, unsigned int *serial)
+{
+	if (!ctx->in_syscall)
+		return 0;
+	if (!ctx->serial)
+		ctx->serial = audit_serial();
+	t->tv_sec  = ctx->ctime.tv_sec;
+	t->tv_nsec = ctx->ctime.tv_nsec;
+	*serial    = ctx->serial;
+	if (!ctx->prio) {
+		ctx->prio = 1;
+		ctx->current_state = AUDIT_RECORD_CONTEXT;
+	}
+	return 1;
+}
+
+/* global counter which is incremented every time something logs in */
+static atomic_t session_id = ATOMIC_INIT(0);
+
+/**
+ * audit_set_loginuid - set current task's audit_context loginuid
+ * @loginuid: loginuid value
+ *
+ * Returns 0.
+ *
+ * Called (set) from fs/proc/base.c::proc_loginuid_write().
+ */
+int audit_set_loginuid(uid_t loginuid)
+{
+	struct task_struct *task = current;
+	struct audit_context *context = task->audit_context;
+	unsigned int sessionid;
+
+#ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
+	if (task->loginuid != -1)
+		return -EPERM;
+#else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
+	if (!capable(CAP_AUDIT_CONTROL))
+		return -EPERM;
+#endif  /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
+
+	sessionid = atomic_inc_return(&session_id);
+	if (context && context->in_syscall) {
+		struct audit_buffer *ab;
+
+		ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
+		if (ab) {
+			audit_log_format(ab, "login pid=%d uid=%u "
+				"old auid=%u new auid=%u"
+				" old ses=%u new ses=%u",
+				task->pid, task_uid(task),
+				task->loginuid, loginuid,
+				task->sessionid, sessionid);
+			audit_log_end(ab);
+		}
+	}
+	task->sessionid = sessionid;
+	task->loginuid = loginuid;
+	return 0;
+}
+
+/**
+ * __audit_mq_open - record audit data for a POSIX MQ open
+ * @oflag: open flag
+ * @mode: mode bits
+ * @attr: queue attributes
+ *
+ */
+void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
+{
+	struct audit_context *context = current->audit_context;
+
+	if (attr)
+		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
+	else
+		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
+
+	context->mq_open.oflag = oflag;
+	context->mq_open.mode = mode;
+
+	context->type = AUDIT_MQ_OPEN;
+}
+
+/**
+ * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
+ * @mqdes: MQ descriptor
+ * @msg_len: Message length
+ * @msg_prio: Message priority
+ * @abs_timeout: Message timeout in absolute time
+ *
+ */
+void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
+			const struct timespec *abs_timeout)
+{
+	struct audit_context *context = current->audit_context;
+	struct timespec *p = &context->mq_sendrecv.abs_timeout;
+
+	if (abs_timeout)
+		memcpy(p, abs_timeout, sizeof(struct timespec));
+	else
+		memset(p, 0, sizeof(struct timespec));
+
+	context->mq_sendrecv.mqdes = mqdes;
+	context->mq_sendrecv.msg_len = msg_len;
+	context->mq_sendrecv.msg_prio = msg_prio;
+
+	context->type = AUDIT_MQ_SENDRECV;
+}
+
+/**
+ * __audit_mq_notify - record audit data for a POSIX MQ notify
+ * @mqdes: MQ descriptor
+ * @notification: Notification event
+ *
+ */
+
+void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
+{
+	struct audit_context *context = current->audit_context;
+
+	if (notification)
+		context->mq_notify.sigev_signo = notification->sigev_signo;
+	else
+		context->mq_notify.sigev_signo = 0;
+
+	context->mq_notify.mqdes = mqdes;
+	context->type = AUDIT_MQ_NOTIFY;
+}
+
+/**
+ * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
+ * @mqdes: MQ descriptor
+ * @mqstat: MQ flags
+ *
+ */
+void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
+{
+	struct audit_context *context = current->audit_context;
+	context->mq_getsetattr.mqdes = mqdes;
+	context->mq_getsetattr.mqstat = *mqstat;
+	context->type = AUDIT_MQ_GETSETATTR;
+}
+
+/**
+ * audit_ipc_obj - record audit data for ipc object
+ * @ipcp: ipc permissions
+ *
+ */
+void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
+{
+	struct audit_context *context = current->audit_context;
+	context->ipc.uid = ipcp->uid;
+	context->ipc.gid = ipcp->gid;
+	context->ipc.mode = ipcp->mode;
+	context->ipc.has_perm = 0;
+	security_ipc_getsecid(ipcp, &context->ipc.osid);
+	context->type = AUDIT_IPC;
+}
+
+/**
+ * audit_ipc_set_perm - record audit data for new ipc permissions
+ * @qbytes: msgq bytes
+ * @uid: msgq user id
+ * @gid: msgq group id
+ * @mode: msgq mode (permissions)
+ *
+ * Called only after audit_ipc_obj().
+ */
+void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
+{
+	struct audit_context *context = current->audit_context;
+
+	context->ipc.qbytes = qbytes;
+	context->ipc.perm_uid = uid;
+	context->ipc.perm_gid = gid;
+	context->ipc.perm_mode = mode;
+	context->ipc.has_perm = 1;
+}
+
+int __audit_bprm(struct linux_binprm *bprm)
+{
+	struct audit_aux_data_execve *ax;
+	struct audit_context *context = current->audit_context;
+
+	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
+	if (!ax)
+		return -ENOMEM;
+
+	ax->argc = bprm->argc;
+	ax->envc = bprm->envc;
+	ax->mm = bprm->mm;
+	ax->d.type = AUDIT_EXECVE;
+	ax->d.next = context->aux;
+	context->aux = (void *)ax;
+	return 0;
+}
+
+
+/**
+ * audit_socketcall - record audit data for sys_socketcall
+ * @nargs: number of args
+ * @args: args array
+ *
+ */
+void __audit_socketcall(int nargs, unsigned long *args)
+{
+	struct audit_context *context = current->audit_context;
+
+	context->type = AUDIT_SOCKETCALL;
+	context->socketcall.nargs = nargs;
+	memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
+}
+
+/**
+ * __audit_fd_pair - record audit data for pipe and socketpair
+ * @fd1: the first file descriptor
+ * @fd2: the second file descriptor
+ *
+ */
+void __audit_fd_pair(int fd1, int fd2)
+{
+	struct audit_context *context = current->audit_context;
+	context->fds[0] = fd1;
+	context->fds[1] = fd2;
+}
+
+/**
+ * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
+ * @len: data length in user space
+ * @a: data address in kernel space
+ *
+ * Returns 0 for success or NULL context or < 0 on error.
+ */
+int __audit_sockaddr(int len, void *a)
+{
+	struct audit_context *context = current->audit_context;
+
+	if (!context->sockaddr) {
+		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
+		if (!p)
+			return -ENOMEM;
+		context->sockaddr = p;
+	}
+
+	context->sockaddr_len = len;
+	memcpy(context->sockaddr, a, len);
+	return 0;
+}
+
+void __audit_ptrace(struct task_struct *t)
+{
+	struct audit_context *context = current->audit_context;
+
+	context->target_pid = t->pid;
+	context->target_auid = audit_get_loginuid(t);
+	context->target_uid = task_uid(t);
+	context->target_sessionid = audit_get_sessionid(t);
+	security_task_getsecid(t, &context->target_sid);
+	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
+}
+
+/**
+ * audit_signal_info - record signal info for shutting down audit subsystem
+ * @sig: signal value
+ * @t: task being signaled
+ *
+ * If the audit subsystem is being terminated, record the task (pid)
+ * and uid that is doing that.
+ */
+int __audit_signal_info(int sig, struct task_struct *t)
+{
+	struct audit_aux_data_pids *axp;
+	struct task_struct *tsk = current;
+	struct audit_context *ctx = tsk->audit_context;
+	uid_t uid = current_uid(), t_uid = task_uid(t);
+
+	if (audit_pid && t->tgid == audit_pid) {
+		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
+			audit_sig_pid = tsk->pid;
+			if (tsk->loginuid != -1)
+				audit_sig_uid = tsk->loginuid;
+			else
+				audit_sig_uid = uid;
+			security_task_getsecid(tsk, &audit_sig_sid);
+		}
+		if (!audit_signals || audit_dummy_context())
+			return 0;
+	}
+
+	/* optimize the common case by putting first signal recipient directly
+	 * in audit_context */
+	if (!ctx->target_pid) {
+		ctx->target_pid = t->tgid;
+		ctx->target_auid = audit_get_loginuid(t);
+		ctx->target_uid = t_uid;
+		ctx->target_sessionid = audit_get_sessionid(t);
+		security_task_getsecid(t, &ctx->target_sid);
+		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
+		return 0;
+	}
+
+	axp = (void *)ctx->aux_pids;
+	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
+		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
+		if (!axp)
+			return -ENOMEM;
+
+		axp->d.type = AUDIT_OBJ_PID;
+		axp->d.next = ctx->aux_pids;
+		ctx->aux_pids = (void *)axp;
+	}
+	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
+
+	axp->target_pid[axp->pid_count] = t->tgid;
+	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
+	axp->target_uid[axp->pid_count] = t_uid;
+	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
+	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
+	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
+	axp->pid_count++;
+
+	return 0;
+}
+
+/**
+ * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
+ * @bprm: pointer to the bprm being processed
+ * @new: the proposed new credentials
+ * @old: the old credentials
+ *
+ * Simply check if the proc already has the caps given by the file and if not
+ * store the priv escalation info for later auditing at the end of the syscall
+ *
+ * -Eric
+ */
+int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
+			   const struct cred *new, const struct cred *old)
+{
+	struct audit_aux_data_bprm_fcaps *ax;
+	struct audit_context *context = current->audit_context;
+	struct cpu_vfs_cap_data vcaps;
+	struct dentry *dentry;
+
+	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
+	if (!ax)
+		return -ENOMEM;
+
+	ax->d.type = AUDIT_BPRM_FCAPS;
+	ax->d.next = context->aux;
+	context->aux = (void *)ax;
+
+	dentry = dget(bprm->file->f_dentry);
+	get_vfs_caps_from_disk(dentry, &vcaps);
+	dput(dentry);
+
+	ax->fcap.permitted = vcaps.permitted;
+	ax->fcap.inheritable = vcaps.inheritable;
+	ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
+	ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;
+
+	ax->old_pcap.permitted   = old->cap_permitted;
+	ax->old_pcap.inheritable = old->cap_inheritable;
+	ax->old_pcap.effective   = old->cap_effective;
+
+	ax->new_pcap.permitted   = new->cap_permitted;
+	ax->new_pcap.inheritable = new->cap_inheritable;
+	ax->new_pcap.effective   = new->cap_effective;
+	return 0;
+}
+
+/**
+ * __audit_log_capset - store information about the arguments to the capset syscall
+ * @pid: target pid of the capset call
+ * @new: the new credentials
+ * @old: the old (current) credentials
+ *
+ * Record the aguments userspace sent to sys_capset for later printing by the
+ * audit system if applicable
+ */
+void __audit_log_capset(pid_t pid,
+		       const struct cred *new, const struct cred *old)
+{
+	struct audit_context *context = current->audit_context;
+	context->capset.pid = pid;
+	context->capset.cap.effective   = new->cap_effective;
+	context->capset.cap.inheritable = new->cap_effective;
+	context->capset.cap.permitted   = new->cap_permitted;
+	context->type = AUDIT_CAPSET;
+}
+
+void __audit_mmap_fd(int fd, int flags)
+{
+	struct audit_context *context = current->audit_context;
+	context->mmap.fd = fd;
+	context->mmap.flags = flags;
+	context->type = AUDIT_MMAP;
+}
+
+static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
+{
+	uid_t auid, uid;
+	gid_t gid;
+	unsigned int sessionid;
+
+	auid = audit_get_loginuid(current);
+	sessionid = audit_get_sessionid(current);
+	current_uid_gid(&uid, &gid);
+
+	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
+			 auid, uid, gid, sessionid);
+	audit_log_task_context(ab);
+	audit_log_format(ab, " pid=%d comm=", current->pid);
+	audit_log_untrustedstring(ab, current->comm);
+	audit_log_format(ab, " reason=");
+	audit_log_string(ab, reason);
+	audit_log_format(ab, " sig=%ld", signr);
+}
+/**
+ * audit_core_dumps - record information about processes that end abnormally
+ * @signr: signal value
+ *
+ * If a process ends with a core dump, something fishy is going on and we
+ * should record the event for investigation.
+ */
+void audit_core_dumps(long signr)
+{
+	struct audit_buffer *ab;
+
+	if (!audit_enabled)
+		return;
+
+	if (signr == SIGQUIT)	/* don't care for those */
+		return;
+
+	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
+	audit_log_abend(ab, "memory violation", signr);
+	audit_log_end(ab);
+}
+
+void __audit_seccomp(unsigned long syscall)
+{
+	struct audit_buffer *ab;
+
+	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
+	audit_log_abend(ab, "seccomp", SIGKILL);
+	audit_log_format(ab, " syscall=%ld", syscall);
+	audit_log_end(ab);
+}
+
+struct list_head *audit_killed_trees(void)
+{
+	struct audit_context *ctx = current->audit_context;
+	if (likely(!ctx || !ctx->in_syscall))
+		return NULL;
+	return &ctx->killed_trees;
+}
diff --git a/kernel/backtracetest.c b/kernel/backtracetest.c
new file mode 100644
index 00000000000..a5e026bc45c
--- /dev/null
+++ b/kernel/backtracetest.c
@@ -0,0 +1,91 @@
+/*
+ * Simple stack backtrace regression test module
+ *
+ * (C) Copyright 2008 Intel Corporation
+ * Author: Arjan van de Ven <arjan@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ */
+
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+
+static void backtrace_test_normal(void)
+{
+	printk("Testing a backtrace from process context.\n");
+	printk("The following trace is a kernel self test and not a bug!\n");
+
+	dump_stack();
+}
+
+static DECLARE_COMPLETION(backtrace_work);
+
+static void backtrace_test_irq_callback(unsigned long data)
+{
+	dump_stack();
+	complete(&backtrace_work);
+}
+
+static DECLARE_TASKLET(backtrace_tasklet, &backtrace_test_irq_callback, 0);
+
+static void backtrace_test_irq(void)
+{
+	printk("Testing a backtrace from irq context.\n");
+	printk("The following trace is a kernel self test and not a bug!\n");
+
+	init_completion(&backtrace_work);
+	tasklet_schedule(&backtrace_tasklet);
+	wait_for_completion(&backtrace_work);
+}
+
+#ifdef CONFIG_STACKTRACE
+static void backtrace_test_saved(void)
+{
+	struct stack_trace trace;
+	unsigned long entries[8];
+
+	printk("Testing a saved backtrace.\n");
+	printk("The following trace is a kernel self test and not a bug!\n");
+
+	trace.nr_entries = 0;
+	trace.max_entries = ARRAY_SIZE(entries);
+	trace.entries = entries;
+	trace.skip = 0;
+
+	save_stack_trace(&trace);
+	print_stack_trace(&trace, 0);
+}
+#else
+static void backtrace_test_saved(void)
+{
+	printk("Saved backtrace test skipped.\n");
+}
+#endif
+
+static int backtrace_regression_test(void)
+{
+	printk("====[ backtrace testing ]===========\n");
+
+	backtrace_test_normal();
+	backtrace_test_irq();
+	backtrace_test_saved();
+
+	printk("====[ end of backtrace testing ]====\n");
+	return 0;
+}
+
+static void exitf(void)
+{
+}
+
+module_init(backtrace_regression_test);
+module_exit(exitf);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
diff --git a/kernel/bounds.c b/kernel/bounds.c
new file mode 100644
index 00000000000..0c9b862292b
--- /dev/null
+++ b/kernel/bounds.c
@@ -0,0 +1,21 @@
+/*
+ * Generate definitions needed by the preprocessor.
+ * This code generates raw asm output which is post-processed
+ * to extract and format the required data.
+ */
+
+#define __GENERATING_BOUNDS_H
+/* Include headers that define the enum constants of interest */
+#include <linux/page-flags.h>
+#include <linux/mmzone.h>
+#include <linux/kbuild.h>
+#include <linux/page_cgroup.h>
+
+void foo(void)
+{
+	/* The enum constants to put into include/generated/bounds.h */
+	DEFINE(NR_PAGEFLAGS, __NR_PAGEFLAGS);
+	DEFINE(MAX_NR_ZONES, __MAX_NR_ZONES);
+	DEFINE(NR_PCG_FLAGS, __NR_PCG_FLAGS);
+	/* End of constants */
+}
diff --git a/kernel/capability.c b/kernel/capability.c
new file mode 100644
index 00000000000..3f1adb6c647
--- /dev/null
+++ b/kernel/capability.c
@@ -0,0 +1,421 @@
+/*
+ * linux/kernel/capability.c
+ *
+ * Copyright (C) 1997  Andrew Main <zefram@fysh.org>
+ *
+ * Integrated into 2.1.97+,  Andrew G. Morgan <morgan@kernel.org>
+ * 30 May 2002:	Cleanup, Robert M. Love <rml@tech9.net>
+ */
+
+#include <linux/audit.h>
+#include <linux/capability.h>
+#include <linux/mm.h>
+#include <linux/export.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/pid_namespace.h>
+#include <linux/user_namespace.h>
+#include <asm/uaccess.h>
+
+/*
+ * Leveraged for setting/resetting capabilities
+ */
+
+const kernel_cap_t __cap_empty_set = CAP_EMPTY_SET;
+
+EXPORT_SYMBOL(__cap_empty_set);
+
+int file_caps_enabled = 1;
+
+static int __init file_caps_disable(char *str)
+{
+	file_caps_enabled = 0;
+	return 1;
+}
+__setup("no_file_caps", file_caps_disable);
+
+/*
+ * More recent versions of libcap are available from:
+ *
+ *   http://www.kernel.org/pub/linux/libs/security/linux-privs/
+ */
+
+static void warn_legacy_capability_use(void)
+{
+	static int warned;
+	if (!warned) {
+		char name[sizeof(current->comm)];
+
+		printk(KERN_INFO "warning: `%s' uses 32-bit capabilities"
+		       " (legacy support in use)\n",
+		       get_task_comm(name, current));
+		warned = 1;
+	}
+}
+
+/*
+ * Version 2 capabilities worked fine, but the linux/capability.h file
+ * that accompanied their introduction encouraged their use without
+ * the necessary user-space source code changes. As such, we have
+ * created a version 3 with equivalent functionality to version 2, but
+ * with a header change to protect legacy source code from using
+ * version 2 when it wanted to use version 1. If your system has code
+ * that trips the following warning, it is using version 2 specific
+ * capabilities and may be doing so insecurely.
+ *
+ * The remedy is to either upgrade your version of libcap (to 2.10+,
+ * if the application is linked against it), or recompile your
+ * application with modern kernel headers and this warning will go
+ * away.
+ */
+
+static void warn_deprecated_v2(void)
+{
+	static int warned;
+
+	if (!warned) {
+		char name[sizeof(current->comm)];
+
+		printk(KERN_INFO "warning: `%s' uses deprecated v2"
+		       " capabilities in a way that may be insecure.\n",
+		       get_task_comm(name, current));
+		warned = 1;
+	}
+}
+
+/*
+ * Version check. Return the number of u32s in each capability flag
+ * array, or a negative value on error.
+ */
+static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy)
+{
+	__u32 version;
+
+	if (get_user(version, &header->version))
+		return -EFAULT;
+
+	switch (version) {
+	case _LINUX_CAPABILITY_VERSION_1:
+		warn_legacy_capability_use();
+		*tocopy = _LINUX_CAPABILITY_U32S_1;
+		break;
+	case _LINUX_CAPABILITY_VERSION_2:
+		warn_deprecated_v2();
+		/*
+		 * fall through - v3 is otherwise equivalent to v2.
+		 */
+	case _LINUX_CAPABILITY_VERSION_3:
+		*tocopy = _LINUX_CAPABILITY_U32S_3;
+		break;
+	default:
+		if (put_user((u32)_KERNEL_CAPABILITY_VERSION, &header->version))
+			return -EFAULT;
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * The only thing that can change the capabilities of the current
+ * process is the current process. As such, we can't be in this code
+ * at the same time as we are in the process of setting capabilities
+ * in this process. The net result is that we can limit our use of
+ * locks to when we are reading the caps of another process.
+ */
+static inline int cap_get_target_pid(pid_t pid, kernel_cap_t *pEp,
+				     kernel_cap_t *pIp, kernel_cap_t *pPp)
+{
+	int ret;
+
+	if (pid && (pid != task_pid_vnr(current))) {
+		struct task_struct *target;
+
+		rcu_read_lock();
+
+		target = find_task_by_vpid(pid);
+		if (!target)
+			ret = -ESRCH;
+		else
+			ret = security_capget(target, pEp, pIp, pPp);
+
+		rcu_read_unlock();
+	} else
+		ret = security_capget(current, pEp, pIp, pPp);
+
+	return ret;
+}
+
+/**
+ * sys_capget - get the capabilities of a given process.
+ * @header: pointer to struct that contains capability version and
+ *	target pid data
+ * @dataptr: pointer to struct that contains the effective, permitted,
+ *	and inheritable capabilities that are returned
+ *
+ * Returns 0 on success and < 0 on error.
+ */
+SYSCALL_DEFINE2(capget, cap_user_header_t, header, cap_user_data_t, dataptr)
+{
+	int ret = 0;
+	pid_t pid;
+	unsigned tocopy;
+	kernel_cap_t pE, pI, pP;
+
+	ret = cap_validate_magic(header, &tocopy);
+	if ((dataptr == NULL) || (ret != 0))
+		return ((dataptr == NULL) && (ret == -EINVAL)) ? 0 : ret;
+
+	if (get_user(pid, &header->pid))
+		return -EFAULT;
+
+	if (pid < 0)
+		return -EINVAL;
+
+	ret = cap_get_target_pid(pid, &pE, &pI, &pP);
+	if (!ret) {
+		struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
+		unsigned i;
+
+		for (i = 0; i < tocopy; i++) {
+			kdata[i].effective = pE.cap[i];
+			kdata[i].permitted = pP.cap[i];
+			kdata[i].inheritable = pI.cap[i];
+		}
+
+		/*
+		 * Note, in the case, tocopy < _KERNEL_CAPABILITY_U32S,
+		 * we silently drop the upper capabilities here. This
+		 * has the effect of making older libcap
+		 * implementations implicitly drop upper capability
+		 * bits when they perform a: capget/modify/capset
+		 * sequence.
+		 *
+		 * This behavior is considered fail-safe
+		 * behavior. Upgrading the application to a newer
+		 * version of libcap will enable access to the newer
+		 * capabilities.
+		 *
+		 * An alternative would be to return an error here
+		 * (-ERANGE), but that causes legacy applications to
+		 * unexpectidly fail; the capget/modify/capset aborts
+		 * before modification is attempted and the application
+		 * fails.
+		 */
+		if (copy_to_user(dataptr, kdata, tocopy
+				 * sizeof(struct __user_cap_data_struct))) {
+			return -EFAULT;
+		}
+	}
+
+	return ret;
+}
+
+/**
+ * sys_capset - set capabilities for a process or (*) a group of processes
+ * @header: pointer to struct that contains capability version and
+ *	target pid data
+ * @data: pointer to struct that contains the effective, permitted,
+ *	and inheritable capabilities
+ *
+ * Set capabilities for the current process only.  The ability to any other
+ * process(es) has been deprecated and removed.
+ *
+ * The restrictions on setting capabilities are specified as:
+ *
+ * I: any raised capabilities must be a subset of the old permitted
+ * P: any raised capabilities must be a subset of the old permitted
+ * E: must be set to a subset of new permitted
+ *
+ * Returns 0 on success and < 0 on error.
+ */
+SYSCALL_DEFINE2(capset, cap_user_header_t, header, const cap_user_data_t, data)
+{
+	struct __user_cap_data_struct kdata[_KERNEL_CAPABILITY_U32S];
+	unsigned i, tocopy, copybytes;
+	kernel_cap_t inheritable, permitted, effective;
+	struct cred *new;
+	int ret;
+	pid_t pid;
+
+	ret = cap_validate_magic(header, &tocopy);
+	if (ret != 0)
+		return ret;
+
+	if (get_user(pid, &header->pid))
+		return -EFAULT;
+
+	/* may only affect current now */
+	if (pid != 0 && pid != task_pid_vnr(current))
+		return -EPERM;
+
+	copybytes = tocopy * sizeof(struct __user_cap_data_struct);
+	if (copybytes > sizeof(kdata))
+		return -EFAULT;
+
+	if (copy_from_user(&kdata, data, copybytes))
+		return -EFAULT;
+
+	for (i = 0; i < tocopy; i++) {
+		effective.cap[i] = kdata[i].effective;
+		permitted.cap[i] = kdata[i].permitted;
+		inheritable.cap[i] = kdata[i].inheritable;
+	}
+	while (i < _KERNEL_CAPABILITY_U32S) {
+		effective.cap[i] = 0;
+		permitted.cap[i] = 0;
+		inheritable.cap[i] = 0;
+		i++;
+	}
+
+	new = prepare_creds();
+	if (!new)
+		return -ENOMEM;
+
+	ret = security_capset(new, current_cred(),
+			      &effective, &inheritable, &permitted);
+	if (ret < 0)
+		goto error;
+
+	audit_log_capset(pid, new, current_cred());
+
+	return commit_creds(new);
+
+error:
+	abort_creds(new);
+	return ret;
+}
+
+/**
+ * has_ns_capability - Does a task have a capability in a specific user ns
+ * @t: The task in question
+ * @ns: target user namespace
+ * @cap: The capability to be tested for
+ *
+ * Return true if the specified task has the given superior capability
+ * currently in effect to the specified user namespace, false if not.
+ *
+ * Note that this does not set PF_SUPERPRIV on the task.
+ */
+bool has_ns_capability(struct task_struct *t,
+		       struct user_namespace *ns, int cap)
+{
+	int ret;
+
+	rcu_read_lock();
+	ret = security_capable(__task_cred(t), ns, cap);
+	rcu_read_unlock();
+
+	return (ret == 0);
+}
+
+/**
+ * has_capability - Does a task have a capability in init_user_ns
+ * @t: The task in question
+ * @cap: The capability to be tested for
+ *
+ * Return true if the specified task has the given superior capability
+ * currently in effect to the initial user namespace, false if not.
+ *
+ * Note that this does not set PF_SUPERPRIV on the task.
+ */
+bool has_capability(struct task_struct *t, int cap)
+{
+	return has_ns_capability(t, &init_user_ns, cap);
+}
+
+/**
+ * has_ns_capability_noaudit - Does a task have a capability (unaudited)
+ * in a specific user ns.
+ * @t: The task in question
+ * @ns: target user namespace
+ * @cap: The capability to be tested for
+ *
+ * Return true if the specified task has the given superior capability
+ * currently in effect to the specified user namespace, false if not.
+ * Do not write an audit message for the check.
+ *
+ * Note that this does not set PF_SUPERPRIV on the task.
+ */
+bool has_ns_capability_noaudit(struct task_struct *t,
+			       struct user_namespace *ns, int cap)
+{
+	int ret;
+
+	rcu_read_lock();
+	ret = security_capable_noaudit(__task_cred(t), ns, cap);
+	rcu_read_unlock();
+
+	return (ret == 0);
+}
+
+/**
+ * has_capability_noaudit - Does a task have a capability (unaudited) in the
+ * initial user ns
+ * @t: The task in question
+ * @cap: The capability to be tested for
+ *
+ * Return true if the specified task has the given superior capability
+ * currently in effect to init_user_ns, false if not.  Don't write an
+ * audit message for the check.
+ *
+ * Note that this does not set PF_SUPERPRIV on the task.
+ */
+bool has_capability_noaudit(struct task_struct *t, int cap)
+{
+	return has_ns_capability_noaudit(t, &init_user_ns, cap);
+}
+
+/**
+ * ns_capable - Determine if the current task has a superior capability in effect
+ * @ns:  The usernamespace we want the capability in
+ * @cap: The capability to be tested for
+ *
+ * Return true if the current task has the given superior capability currently
+ * available for use, false if not.
+ *
+ * This sets PF_SUPERPRIV on the task if the capability is available on the
+ * assumption that it's about to be used.
+ */
+bool ns_capable(struct user_namespace *ns, int cap)
+{
+	if (unlikely(!cap_valid(cap))) {
+		printk(KERN_CRIT "capable() called with invalid cap=%u\n", cap);
+		BUG();
+	}
+
+	if (security_capable(current_cred(), ns, cap) == 0) {
+		current->flags |= PF_SUPERPRIV;
+		return true;
+	}
+	return false;
+}
+EXPORT_SYMBOL(ns_capable);
+
+/**
+ * capable - Determine if the current task has a superior capability in effect
+ * @cap: The capability to be tested for
+ *
+ * Return true if the current task has the given superior capability currently
+ * available for use, false if not.
+ *
+ * This sets PF_SUPERPRIV on the task if the capability is available on the
+ * assumption that it's about to be used.
+ */
+bool capable(int cap)
+{
+	return ns_capable(&init_user_ns, cap);
+}
+EXPORT_SYMBOL(capable);
+
+/**
+ * nsown_capable - Check superior capability to one's own user_ns
+ * @cap: The capability in question
+ *
+ * Return true if the current task has the given superior capability
+ * targeted at its own user namespace.
+ */
+bool nsown_capable(int cap)
+{
+	return ns_capable(current_user_ns(), cap);
+}
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
new file mode 100644
index 00000000000..a5d3b5325f7
--- /dev/null
+++ b/kernel/cgroup.c
@@ -0,0 +1,5289 @@
+/*
+ *  Generic process-grouping system.
+ *
+ *  Based originally on the cpuset system, extracted by Paul Menage
+ *  Copyright (C) 2006 Google, Inc
+ *
+ *  Notifications support
+ *  Copyright (C) 2009 Nokia Corporation
+ *  Author: Kirill A. Shutemov
+ *
+ *  Copyright notices from the original cpuset code:
+ *  --------------------------------------------------
+ *  Copyright (C) 2003 BULL SA.
+ *  Copyright (C) 2004-2006 Silicon Graphics, Inc.
+ *
+ *  Portions derived from Patrick Mochel's sysfs code.
+ *  sysfs is Copyright (c) 2001-3 Patrick Mochel
+ *
+ *  2003-10-10 Written by Simon Derr.
+ *  2003-10-22 Updates by Stephen Hemminger.
+ *  2004 May-July Rework by Paul Jackson.
+ *  ---------------------------------------------------
+ *
+ *  This file is subject to the terms and conditions of the GNU General Public
+ *  License.  See the file COPYING in the main directory of the Linux
+ *  distribution for more details.
+ */
+
+#include <linux/cgroup.h>
+#include <linux/cred.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/init_task.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/proc_fs.h>
+#include <linux/rcupdate.h>
+#include <linux/sched.h>
+#include <linux/backing-dev.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/magic.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/sort.h>
+#include <linux/kmod.h>
+#include <linux/module.h>
+#include <linux/delayacct.h>
+#include <linux/cgroupstats.h>
+#include <linux/hash.h>
+#include <linux/namei.h>
+#include <linux/pid_namespace.h>
+#include <linux/idr.h>
+#include <linux/vmalloc.h> /* TODO: replace with more sophisticated array */
+#include <linux/eventfd.h>
+#include <linux/poll.h>
+#include <linux/flex_array.h> /* used in cgroup_attach_proc */
+
+#include <linux/atomic.h>
+
+/*
+ * cgroup_mutex is the master lock.  Any modification to cgroup or its
+ * hierarchy must be performed while holding it.
+ *
+ * cgroup_root_mutex nests inside cgroup_mutex and should be held to modify
+ * cgroupfs_root of any cgroup hierarchy - subsys list, flags,
+ * release_agent_path and so on.  Modifying requires both cgroup_mutex and
+ * cgroup_root_mutex.  Readers can acquire either of the two.  This is to
+ * break the following locking order cycle.
+ *
+ *  A. cgroup_mutex -> cred_guard_mutex -> s_type->i_mutex_key -> namespace_sem
+ *  B. namespace_sem -> cgroup_mutex
+ *
+ * B happens only through cgroup_show_options() and using cgroup_root_mutex
+ * breaks it.
+ */
+static DEFINE_MUTEX(cgroup_mutex);
+static DEFINE_MUTEX(cgroup_root_mutex);
+
+/*
+ * Generate an array of cgroup subsystem pointers. At boot time, this is
+ * populated up to CGROUP_BUILTIN_SUBSYS_COUNT, and modular subsystems are
+ * registered after that. The mutable section of this array is protected by
+ * cgroup_mutex.
+ */
+#define SUBSYS(_x) &_x ## _subsys,
+static struct cgroup_subsys *subsys[CGROUP_SUBSYS_COUNT] = {
+#include <linux/cgroup_subsys.h>
+};
+
+#define MAX_CGROUP_ROOT_NAMELEN 64
+
+/*
+ * A cgroupfs_root represents the root of a cgroup hierarchy,
+ * and may be associated with a superblock to form an active
+ * hierarchy
+ */
+struct cgroupfs_root {
+	struct super_block *sb;
+
+	/*
+	 * The bitmask of subsystems intended to be attached to this
+	 * hierarchy
+	 */
+	unsigned long subsys_bits;
+
+	/* Unique id for this hierarchy. */
+	int hierarchy_id;
+
+	/* The bitmask of subsystems currently attached to this hierarchy */
+	unsigned long actual_subsys_bits;
+
+	/* A list running through the attached subsystems */
+	struct list_head subsys_list;
+
+	/* The root cgroup for this hierarchy */
+	struct cgroup top_cgroup;
+
+	/* Tracks how many cgroups are currently defined in hierarchy.*/
+	int number_of_cgroups;
+
+	/* A list running through the active hierarchies */
+	struct list_head root_list;
+
+	/* Hierarchy-specific flags */
+	unsigned long flags;
+
+	/* The path to use for release notifications. */
+	char release_agent_path[PATH_MAX];
+
+	/* The name for this hierarchy - may be empty */
+	char name[MAX_CGROUP_ROOT_NAMELEN];
+};
+
+/*
+ * The "rootnode" hierarchy is the "dummy hierarchy", reserved for the
+ * subsystems that are otherwise unattached - it never has more than a
+ * single cgroup, and all tasks are part of that cgroup.
+ */
+static struct cgroupfs_root rootnode;
+
+/*
+ * CSS ID -- ID per subsys's Cgroup Subsys State(CSS). used only when
+ * cgroup_subsys->use_id != 0.
+ */
+#define CSS_ID_MAX	(65535)
+struct css_id {
+	/*
+	 * The css to which this ID points. This pointer is set to valid value
+	 * after cgroup is populated. If cgroup is removed, this will be NULL.
+	 * This pointer is expected to be RCU-safe because destroy()
+	 * is called after synchronize_rcu(). But for safe use, css_is_removed()
+	 * css_tryget() should be used for avoiding race.
+	 */
+	struct cgroup_subsys_state __rcu *css;
+	/*
+	 * ID of this css.
+	 */
+	unsigned short id;
+	/*
+	 * Depth in hierarchy which this ID belongs to.
+	 */
+	unsigned short depth;
+	/*
+	 * ID is freed by RCU. (and lookup routine is RCU safe.)
+	 */
+	struct rcu_head rcu_head;
+	/*
+	 * Hierarchy of CSS ID belongs to.
+	 */
+	unsigned short stack[0]; /* Array of Length (depth+1) */
+};
+
+/*
+ * cgroup_event represents events which userspace want to receive.
+ */
+struct cgroup_event {
+	/*
+	 * Cgroup which the event belongs to.
+	 */
+	struct cgroup *cgrp;
+	/*
+	 * Control file which the event associated.
+	 */
+	struct cftype *cft;
+	/*
+	 * eventfd to signal userspace about the event.
+	 */
+	struct eventfd_ctx *eventfd;
+	/*
+	 * Each of these stored in a list by the cgroup.
+	 */
+	struct list_head list;
+	/*
+	 * All fields below needed to unregister event when
+	 * userspace closes eventfd.
+	 */
+	poll_table pt;
+	wait_queue_head_t *wqh;
+	wait_queue_t wait;
+	struct work_struct remove;
+};
+
+/* The list of hierarchy roots */
+
+static LIST_HEAD(roots);
+static int root_count;
+
+static DEFINE_IDA(hierarchy_ida);
+static int next_hierarchy_id;
+static DEFINE_SPINLOCK(hierarchy_id_lock);
+
+/* dummytop is a shorthand for the dummy hierarchy's top cgroup */
+#define dummytop (&rootnode.top_cgroup)
+
+/* This flag indicates whether tasks in the fork and exit paths should
+ * check for fork/exit handlers to call. This avoids us having to do
+ * extra work in the fork/exit path if none of the subsystems need to
+ * be called.
+ */
+static int need_forkexit_callback __read_mostly;
+
+#ifdef CONFIG_PROVE_LOCKING
+int cgroup_lock_is_held(void)
+{
+	return lockdep_is_held(&cgroup_mutex);
+}
+#else /* #ifdef CONFIG_PROVE_LOCKING */
+int cgroup_lock_is_held(void)
+{
+	return mutex_is_locked(&cgroup_mutex);
+}
+#endif /* #else #ifdef CONFIG_PROVE_LOCKING */
+
+EXPORT_SYMBOL_GPL(cgroup_lock_is_held);
+
+/* convenient tests for these bits */
+inline int cgroup_is_removed(const struct cgroup *cgrp)
+{
+	return test_bit(CGRP_REMOVED, &cgrp->flags);
+}
+
+/* bits in struct cgroupfs_root flags field */
+enum {
+	ROOT_NOPREFIX, /* mounted subsystems have no named prefix */
+};
+
+static int cgroup_is_releasable(const struct cgroup *cgrp)
+{
+	const int bits =
+		(1 << CGRP_RELEASABLE) |
+		(1 << CGRP_NOTIFY_ON_RELEASE);
+	return (cgrp->flags & bits) == bits;
+}
+
+static int notify_on_release(const struct cgroup *cgrp)
+{
+	return test_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
+}
+
+static int clone_children(const struct cgroup *cgrp)
+{
+	return test_bit(CGRP_CLONE_CHILDREN, &cgrp->flags);
+}
+
+/*
+ * for_each_subsys() allows you to iterate on each subsystem attached to
+ * an active hierarchy
+ */
+#define for_each_subsys(_root, _ss) \
+list_for_each_entry(_ss, &_root->subsys_list, sibling)
+
+/* for_each_active_root() allows you to iterate across the active hierarchies */
+#define for_each_active_root(_root) \
+list_for_each_entry(_root, &roots, root_list)
+
+/* the list of cgroups eligible for automatic release. Protected by
+ * release_list_lock */
+static LIST_HEAD(release_list);
+static DEFINE_RAW_SPINLOCK(release_list_lock);
+static void cgroup_release_agent(struct work_struct *work);
+static DECLARE_WORK(release_agent_work, cgroup_release_agent);
+static void check_for_release(struct cgroup *cgrp);
+
+/* Link structure for associating css_set objects with cgroups */
+struct cg_cgroup_link {
+	/*
+	 * List running through cg_cgroup_links associated with a
+	 * cgroup, anchored on cgroup->css_sets
+	 */
+	struct list_head cgrp_link_list;
+	struct cgroup *cgrp;
+	/*
+	 * List running through cg_cgroup_links pointing at a
+	 * single css_set object, anchored on css_set->cg_links
+	 */
+	struct list_head cg_link_list;
+	struct css_set *cg;
+};
+
+/* The default css_set - used by init and its children prior to any
+ * hierarchies being mounted. It contains a pointer to the root state
+ * for each subsystem. Also used to anchor the list of css_sets. Not
+ * reference-counted, to improve performance when child cgroups
+ * haven't been created.
+ */
+
+static struct css_set init_css_set;
+static struct cg_cgroup_link init_css_set_link;
+
+static int cgroup_init_idr(struct cgroup_subsys *ss,
+			   struct cgroup_subsys_state *css);
+
+/* css_set_lock protects the list of css_set objects, and the
+ * chain of tasks off each css_set.  Nests outside task->alloc_lock
+ * due to cgroup_iter_start() */
+static DEFINE_RWLOCK(css_set_lock);
+static int css_set_count;
+
+/*
+ * hash table for cgroup groups. This improves the performance to find
+ * an existing css_set. This hash doesn't (currently) take into
+ * account cgroups in empty hierarchies.
+ */
+#define CSS_SET_HASH_BITS	7
+#define CSS_SET_TABLE_SIZE	(1 << CSS_SET_HASH_BITS)
+static struct hlist_head css_set_table[CSS_SET_TABLE_SIZE];
+
+static struct hlist_head *css_set_hash(struct cgroup_subsys_state *css[])
+{
+	int i;
+	int index;
+	unsigned long tmp = 0UL;
+
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++)
+		tmp += (unsigned long)css[i];
+	tmp = (tmp >> 16) ^ tmp;
+
+	index = hash_long(tmp, CSS_SET_HASH_BITS);
+
+	return &css_set_table[index];
+}
+
+/* We don't maintain the lists running through each css_set to its
+ * task until after the first call to cgroup_iter_start(). This
+ * reduces the fork()/exit() overhead for people who have cgroups
+ * compiled into their kernel but not actually in use */
+static int use_task_css_set_links __read_mostly;
+
+static void __put_css_set(struct css_set *cg, int taskexit)
+{
+	struct cg_cgroup_link *link;
+	struct cg_cgroup_link *saved_link;
+	/*
+	 * Ensure that the refcount doesn't hit zero while any readers
+	 * can see it. Similar to atomic_dec_and_lock(), but for an
+	 * rwlock
+	 */
+	if (atomic_add_unless(&cg->refcount, -1, 1))
+		return;
+	write_lock(&css_set_lock);
+	if (!atomic_dec_and_test(&cg->refcount)) {
+		write_unlock(&css_set_lock);
+		return;
+	}
+
+	/* This css_set is dead. unlink it and release cgroup refcounts */
+	hlist_del(&cg->hlist);
+	css_set_count--;
+
+	list_for_each_entry_safe(link, saved_link, &cg->cg_links,
+				 cg_link_list) {
+		struct cgroup *cgrp = link->cgrp;
+		list_del(&link->cg_link_list);
+		list_del(&link->cgrp_link_list);
+		if (atomic_dec_and_test(&cgrp->count) &&
+		    notify_on_release(cgrp)) {
+			if (taskexit)
+				set_bit(CGRP_RELEASABLE, &cgrp->flags);
+			check_for_release(cgrp);
+		}
+
+		kfree(link);
+	}
+
+	write_unlock(&css_set_lock);
+	kfree_rcu(cg, rcu_head);
+}
+
+/*
+ * refcounted get/put for css_set objects
+ */
+static inline void get_css_set(struct css_set *cg)
+{
+	atomic_inc(&cg->refcount);
+}
+
+static inline void put_css_set(struct css_set *cg)
+{
+	__put_css_set(cg, 0);
+}
+
+static inline void put_css_set_taskexit(struct css_set *cg)
+{
+	__put_css_set(cg, 1);
+}
+
+/*
+ * compare_css_sets - helper function for find_existing_css_set().
+ * @cg: candidate css_set being tested
+ * @old_cg: existing css_set for a task
+ * @new_cgrp: cgroup that's being entered by the task
+ * @template: desired set of css pointers in css_set (pre-calculated)
+ *
+ * Returns true if "cg" matches "old_cg" except for the hierarchy
+ * which "new_cgrp" belongs to, for which it should match "new_cgrp".
+ */
+static bool compare_css_sets(struct css_set *cg,
+			     struct css_set *old_cg,
+			     struct cgroup *new_cgrp,
+			     struct cgroup_subsys_state *template[])
+{
+	struct list_head *l1, *l2;
+
+	if (memcmp(template, cg->subsys, sizeof(cg->subsys))) {
+		/* Not all subsystems matched */
+		return false;
+	}
+
+	/*
+	 * Compare cgroup pointers in order to distinguish between
+	 * different cgroups in heirarchies with no subsystems. We
+	 * could get by with just this check alone (and skip the
+	 * memcmp above) but on most setups the memcmp check will
+	 * avoid the need for this more expensive check on almost all
+	 * candidates.
+	 */
+
+	l1 = &cg->cg_links;
+	l2 = &old_cg->cg_links;
+	while (1) {
+		struct cg_cgroup_link *cgl1, *cgl2;
+		struct cgroup *cg1, *cg2;
+
+		l1 = l1->next;
+		l2 = l2->next;
+		/* See if we reached the end - both lists are equal length. */
+		if (l1 == &cg->cg_links) {
+			BUG_ON(l2 != &old_cg->cg_links);
+			break;
+		} else {
+			BUG_ON(l2 == &old_cg->cg_links);
+		}
+		/* Locate the cgroups associated with these links. */
+		cgl1 = list_entry(l1, struct cg_cgroup_link, cg_link_list);
+		cgl2 = list_entry(l2, struct cg_cgroup_link, cg_link_list);
+		cg1 = cgl1->cgrp;
+		cg2 = cgl2->cgrp;
+		/* Hierarchies should be linked in the same order. */
+		BUG_ON(cg1->root != cg2->root);
+
+		/*
+		 * If this hierarchy is the hierarchy of the cgroup
+		 * that's changing, then we need to check that this
+		 * css_set points to the new cgroup; if it's any other
+		 * hierarchy, then this css_set should point to the
+		 * same cgroup as the old css_set.
+		 */
+		if (cg1->root == new_cgrp->root) {
+			if (cg1 != new_cgrp)
+				return false;
+		} else {
+			if (cg1 != cg2)
+				return false;
+		}
+	}
+	return true;
+}
+
+/*
+ * find_existing_css_set() is a helper for
+ * find_css_set(), and checks to see whether an existing
+ * css_set is suitable.
+ *
+ * oldcg: the cgroup group that we're using before the cgroup
+ * transition
+ *
+ * cgrp: the cgroup that we're moving into
+ *
+ * template: location in which to build the desired set of subsystem
+ * state objects for the new cgroup group
+ */
+static struct css_set *find_existing_css_set(
+	struct css_set *oldcg,
+	struct cgroup *cgrp,
+	struct cgroup_subsys_state *template[])
+{
+	int i;
+	struct cgroupfs_root *root = cgrp->root;
+	struct hlist_head *hhead;
+	struct hlist_node *node;
+	struct css_set *cg;
+
+	/*
+	 * Build the set of subsystem state objects that we want to see in the
+	 * new css_set. while subsystems can change globally, the entries here
+	 * won't change, so no need for locking.
+	 */
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+		if (root->subsys_bits & (1UL << i)) {
+			/* Subsystem is in this hierarchy. So we want
+			 * the subsystem state from the new
+			 * cgroup */
+			template[i] = cgrp->subsys[i];
+		} else {
+			/* Subsystem is not in this hierarchy, so we
+			 * don't want to change the subsystem state */
+			template[i] = oldcg->subsys[i];
+		}
+	}
+
+	hhead = css_set_hash(template);
+	hlist_for_each_entry(cg, node, hhead, hlist) {
+		if (!compare_css_sets(cg, oldcg, cgrp, template))
+			continue;
+
+		/* This css_set matches what we need */
+		return cg;
+	}
+
+	/* No existing cgroup group matched */
+	return NULL;
+}
+
+static void free_cg_links(struct list_head *tmp)
+{
+	struct cg_cgroup_link *link;
+	struct cg_cgroup_link *saved_link;
+
+	list_for_each_entry_safe(link, saved_link, tmp, cgrp_link_list) {
+		list_del(&link->cgrp_link_list);
+		kfree(link);
+	}
+}
+
+/*
+ * allocate_cg_links() allocates "count" cg_cgroup_link structures
+ * and chains them on tmp through their cgrp_link_list fields. Returns 0 on
+ * success or a negative error
+ */
+static int allocate_cg_links(int count, struct list_head *tmp)
+{
+	struct cg_cgroup_link *link;
+	int i;
+	INIT_LIST_HEAD(tmp);
+	for (i = 0; i < count; i++) {
+		link = kmalloc(sizeof(*link), GFP_KERNEL);
+		if (!link) {
+			free_cg_links(tmp);
+			return -ENOMEM;
+		}
+		list_add(&link->cgrp_link_list, tmp);
+	}
+	return 0;
+}
+
+/**
+ * link_css_set - a helper function to link a css_set to a cgroup
+ * @tmp_cg_links: cg_cgroup_link objects allocated by allocate_cg_links()
+ * @cg: the css_set to be linked
+ * @cgrp: the destination cgroup
+ */
+static void link_css_set(struct list_head *tmp_cg_links,
+			 struct css_set *cg, struct cgroup *cgrp)
+{
+	struct cg_cgroup_link *link;
+
+	BUG_ON(list_empty(tmp_cg_links));
+	link = list_first_entry(tmp_cg_links, struct cg_cgroup_link,
+				cgrp_link_list);
+	link->cg = cg;
+	link->cgrp = cgrp;
+	atomic_inc(&cgrp->count);
+	list_move(&link->cgrp_link_list, &cgrp->css_sets);
+	/*
+	 * Always add links to the tail of the list so that the list
+	 * is sorted by order of hierarchy creation
+	 */
+	list_add_tail(&link->cg_link_list, &cg->cg_links);
+}
+
+/*
+ * find_css_set() takes an existing cgroup group and a
+ * cgroup object, and returns a css_set object that's
+ * equivalent to the old group, but with the given cgroup
+ * substituted into the appropriate hierarchy. Must be called with
+ * cgroup_mutex held
+ */
+static struct css_set *find_css_set(
+	struct css_set *oldcg, struct cgroup *cgrp)
+{
+	struct css_set *res;
+	struct cgroup_subsys_state *template[CGROUP_SUBSYS_COUNT];
+
+	struct list_head tmp_cg_links;
+
+	struct hlist_head *hhead;
+	struct cg_cgroup_link *link;
+
+	/* First see if we already have a cgroup group that matches
+	 * the desired set */
+	read_lock(&css_set_lock);
+	res = find_existing_css_set(oldcg, cgrp, template);
+	if (res)
+		get_css_set(res);
+	read_unlock(&css_set_lock);
+
+	if (res)
+		return res;
+
+	res = kmalloc(sizeof(*res), GFP_KERNEL);
+	if (!res)
+		return NULL;
+
+	/* Allocate all the cg_cgroup_link objects that we'll need */
+	if (allocate_cg_links(root_count, &tmp_cg_links) < 0) {
+		kfree(res);
+		return NULL;
+	}
+
+	atomic_set(&res->refcount, 1);
+	INIT_LIST_HEAD(&res->cg_links);
+	INIT_LIST_HEAD(&res->tasks);
+	INIT_HLIST_NODE(&res->hlist);
+
+	/* Copy the set of subsystem state objects generated in
+	 * find_existing_css_set() */
+	memcpy(res->subsys, template, sizeof(res->subsys));
+
+	write_lock(&css_set_lock);
+	/* Add reference counts and links from the new css_set. */
+	list_for_each_entry(link, &oldcg->cg_links, cg_link_list) {
+		struct cgroup *c = link->cgrp;
+		if (c->root == cgrp->root)
+			c = cgrp;
+		link_css_set(&tmp_cg_links, res, c);
+	}
+
+	BUG_ON(!list_empty(&tmp_cg_links));
+
+	css_set_count++;
+
+	/* Add this cgroup group to the hash table */
+	hhead = css_set_hash(res->subsys);
+	hlist_add_head(&res->hlist, hhead);
+
+	write_unlock(&css_set_lock);
+
+	return res;
+}
+
+/*
+ * Return the cgroup for "task" from the given hierarchy. Must be
+ * called with cgroup_mutex held.
+ */
+static struct cgroup *task_cgroup_from_root(struct task_struct *task,
+					    struct cgroupfs_root *root)
+{
+	struct css_set *css;
+	struct cgroup *res = NULL;
+
+	BUG_ON(!mutex_is_locked(&cgroup_mutex));
+	read_lock(&css_set_lock);
+	/*
+	 * No need to lock the task - since we hold cgroup_mutex the
+	 * task can't change groups, so the only thing that can happen
+	 * is that it exits and its css is set back to init_css_set.
+	 */
+	css = task->cgroups;
+	if (css == &init_css_set) {
+		res = &root->top_cgroup;
+	} else {
+		struct cg_cgroup_link *link;
+		list_for_each_entry(link, &css->cg_links, cg_link_list) {
+			struct cgroup *c = link->cgrp;
+			if (c->root == root) {
+				res = c;
+				break;
+			}
+		}
+	}
+	read_unlock(&css_set_lock);
+	BUG_ON(!res);
+	return res;
+}
+
+/*
+ * There is one global cgroup mutex. We also require taking
+ * task_lock() when dereferencing a task's cgroup subsys pointers.
+ * See "The task_lock() exception", at the end of this comment.
+ *
+ * A task must hold cgroup_mutex to modify cgroups.
+ *
+ * Any task can increment and decrement the count field without lock.
+ * So in general, code holding cgroup_mutex can't rely on the count
+ * field not changing.  However, if the count goes to zero, then only
+ * cgroup_attach_task() can increment it again.  Because a count of zero
+ * means that no tasks are currently attached, therefore there is no
+ * way a task attached to that cgroup can fork (the other way to
+ * increment the count).  So code holding cgroup_mutex can safely
+ * assume that if the count is zero, it will stay zero. Similarly, if
+ * a task holds cgroup_mutex on a cgroup with zero count, it
+ * knows that the cgroup won't be removed, as cgroup_rmdir()
+ * needs that mutex.
+ *
+ * The fork and exit callbacks cgroup_fork() and cgroup_exit(), don't
+ * (usually) take cgroup_mutex.  These are the two most performance
+ * critical pieces of code here.  The exception occurs on cgroup_exit(),
+ * when a task in a notify_on_release cgroup exits.  Then cgroup_mutex
+ * is taken, and if the cgroup count is zero, a usermode call made
+ * to the release agent with the name of the cgroup (path relative to
+ * the root of cgroup file system) as the argument.
+ *
+ * A cgroup can only be deleted if both its 'count' of using tasks
+ * is zero, and its list of 'children' cgroups is empty.  Since all
+ * tasks in the system use _some_ cgroup, and since there is always at
+ * least one task in the system (init, pid == 1), therefore, top_cgroup
+ * always has either children cgroups and/or using tasks.  So we don't
+ * need a special hack to ensure that top_cgroup cannot be deleted.
+ *
+ *	The task_lock() exception
+ *
+ * The need for this exception arises from the action of
+ * cgroup_attach_task(), which overwrites one tasks cgroup pointer with
+ * another.  It does so using cgroup_mutex, however there are
+ * several performance critical places that need to reference
+ * task->cgroup without the expense of grabbing a system global
+ * mutex.  Therefore except as noted below, when dereferencing or, as
+ * in cgroup_attach_task(), modifying a task'ss cgroup pointer we use
+ * task_lock(), which acts on a spinlock (task->alloc_lock) already in
+ * the task_struct routinely used for such matters.
+ *
+ * P.S.  One more locking exception.  RCU is used to guard the
+ * update of a tasks cgroup pointer by cgroup_attach_task()
+ */
+
+/**
+ * cgroup_lock - lock out any changes to cgroup structures
+ *
+ */
+void cgroup_lock(void)
+{
+	mutex_lock(&cgroup_mutex);
+}
+EXPORT_SYMBOL_GPL(cgroup_lock);
+
+/**
+ * cgroup_unlock - release lock on cgroup changes
+ *
+ * Undo the lock taken in a previous cgroup_lock() call.
+ */
+void cgroup_unlock(void)
+{
+	mutex_unlock(&cgroup_mutex);
+}
+EXPORT_SYMBOL_GPL(cgroup_unlock);
+
+/*
+ * A couple of forward declarations required, due to cyclic reference loop:
+ * cgroup_mkdir -> cgroup_create -> cgroup_populate_dir ->
+ * cgroup_add_file -> cgroup_create_file -> cgroup_dir_inode_operations
+ * -> cgroup_mkdir.
+ */
+
+static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
+static struct dentry *cgroup_lookup(struct inode *, struct dentry *, struct nameidata *);
+static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
+static int cgroup_populate_dir(struct cgroup *cgrp);
+static const struct inode_operations cgroup_dir_inode_operations;
+static const struct file_operations proc_cgroupstats_operations;
+
+static struct backing_dev_info cgroup_backing_dev_info = {
+	.name		= "cgroup",
+	.capabilities	= BDI_CAP_NO_ACCT_AND_WRITEBACK,
+};
+
+static int alloc_css_id(struct cgroup_subsys *ss,
+			struct cgroup *parent, struct cgroup *child);
+
+static struct inode *cgroup_new_inode(umode_t mode, struct super_block *sb)
+{
+	struct inode *inode = new_inode(sb);
+
+	if (inode) {
+		inode->i_ino = get_next_ino();
+		inode->i_mode = mode;
+		inode->i_uid = current_fsuid();
+		inode->i_gid = current_fsgid();
+		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+		inode->i_mapping->backing_dev_info = &cgroup_backing_dev_info;
+	}
+	return inode;
+}
+
+/*
+ * Call subsys's pre_destroy handler.
+ * This is called before css refcnt check.
+ */
+static int cgroup_call_pre_destroy(struct cgroup *cgrp)
+{
+	struct cgroup_subsys *ss;
+	int ret = 0;
+
+	for_each_subsys(cgrp->root, ss)
+		if (ss->pre_destroy) {
+			ret = ss->pre_destroy(ss, cgrp);
+			if (ret)
+				break;
+		}
+
+	return ret;
+}
+
+static void cgroup_diput(struct dentry *dentry, struct inode *inode)
+{
+	/* is dentry a directory ? if so, kfree() associated cgroup */
+	if (S_ISDIR(inode->i_mode)) {
+		struct cgroup *cgrp = dentry->d_fsdata;
+		struct cgroup_subsys *ss;
+		BUG_ON(!(cgroup_is_removed(cgrp)));
+		/* It's possible for external users to be holding css
+		 * reference counts on a cgroup; css_put() needs to
+		 * be able to access the cgroup after decrementing
+		 * the reference count in order to know if it needs to
+		 * queue the cgroup to be handled by the release
+		 * agent */
+		synchronize_rcu();
+
+		mutex_lock(&cgroup_mutex);
+		/*
+		 * Release the subsystem state objects.
+		 */
+		for_each_subsys(cgrp->root, ss)
+			ss->destroy(ss, cgrp);
+
+		cgrp->root->number_of_cgroups--;
+		mutex_unlock(&cgroup_mutex);
+
+		/*
+		 * Drop the active superblock reference that we took when we
+		 * created the cgroup
+		 */
+		deactivate_super(cgrp->root->sb);
+
+		/*
+		 * if we're getting rid of the cgroup, refcount should ensure
+		 * that there are no pidlists left.
+		 */
+		BUG_ON(!list_empty(&cgrp->pidlists));
+
+		kfree_rcu(cgrp, rcu_head);
+	}
+	iput(inode);
+}
+
+static int cgroup_delete(const struct dentry *d)
+{
+	return 1;
+}
+
+static void remove_dir(struct dentry *d)
+{
+	struct dentry *parent = dget(d->d_parent);
+
+	d_delete(d);
+	simple_rmdir(parent->d_inode, d);
+	dput(parent);
+}
+
+static void cgroup_clear_directory(struct dentry *dentry)
+{
+	struct list_head *node;
+
+	BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
+	spin_lock(&dentry->d_lock);
+	node = dentry->d_subdirs.next;
+	while (node != &dentry->d_subdirs) {
+		struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
+
+		spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
+		list_del_init(node);
+		if (d->d_inode) {
+			/* This should never be called on a cgroup
+			 * directory with child cgroups */
+			BUG_ON(d->d_inode->i_mode & S_IFDIR);
+			dget_dlock(d);
+			spin_unlock(&d->d_lock);
+			spin_unlock(&dentry->d_lock);
+			d_delete(d);
+			simple_unlink(dentry->d_inode, d);
+			dput(d);
+			spin_lock(&dentry->d_lock);
+		} else
+			spin_unlock(&d->d_lock);
+		node = dentry->d_subdirs.next;
+	}
+	spin_unlock(&dentry->d_lock);
+}
+
+/*
+ * NOTE : the dentry must have been dget()'ed
+ */
+static void cgroup_d_remove_dir(struct dentry *dentry)
+{
+	struct dentry *parent;
+
+	cgroup_clear_directory(dentry);
+
+	parent = dentry->d_parent;
+	spin_lock(&parent->d_lock);
+	spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
+	list_del_init(&dentry->d_u.d_child);
+	spin_unlock(&dentry->d_lock);
+	spin_unlock(&parent->d_lock);
+	remove_dir(dentry);
+}
+
+/*
+ * A queue for waiters to do rmdir() cgroup. A tasks will sleep when
+ * cgroup->count == 0 && list_empty(&cgroup->children) && subsys has some
+ * reference to css->refcnt. In general, this refcnt is expected to goes down
+ * to zero, soon.
+ *
+ * CGRP_WAIT_ON_RMDIR flag is set under cgroup's inode->i_mutex;
+ */
+static DECLARE_WAIT_QUEUE_HEAD(cgroup_rmdir_waitq);
+
+static void cgroup_wakeup_rmdir_waiter(struct cgroup *cgrp)
+{
+	if (unlikely(test_and_clear_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags)))
+		wake_up_all(&cgroup_rmdir_waitq);
+}
+
+void cgroup_exclude_rmdir(struct cgroup_subsys_state *css)
+{
+	css_get(css);
+}
+
+void cgroup_release_and_wakeup_rmdir(struct cgroup_subsys_state *css)
+{
+	cgroup_wakeup_rmdir_waiter(css->cgroup);
+	css_put(css);
+}
+
+/*
+ * Call with cgroup_mutex held. Drops reference counts on modules, including
+ * any duplicate ones that parse_cgroupfs_options took. If this function
+ * returns an error, no reference counts are touched.
+ */
+static int rebind_subsystems(struct cgroupfs_root *root,
+			      unsigned long final_bits)
+{
+	unsigned long added_bits, removed_bits;
+	struct cgroup *cgrp = &root->top_cgroup;
+	int i;
+
+	BUG_ON(!mutex_is_locked(&cgroup_mutex));
+	BUG_ON(!mutex_is_locked(&cgroup_root_mutex));
+
+	removed_bits = root->actual_subsys_bits & ~final_bits;
+	added_bits = final_bits & ~root->actual_subsys_bits;
+	/* Check that any added subsystems are currently free */
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+		unsigned long bit = 1UL << i;
+		struct cgroup_subsys *ss = subsys[i];
+		if (!(bit & added_bits))
+			continue;
+		/*
+		 * Nobody should tell us to do a subsys that doesn't exist:
+		 * parse_cgroupfs_options should catch that case and refcounts
+		 * ensure that subsystems won't disappear once selected.
+		 */
+		BUG_ON(ss == NULL);
+		if (ss->root != &rootnode) {
+			/* Subsystem isn't free */
+			return -EBUSY;
+		}
+	}
+
+	/* Currently we don't handle adding/removing subsystems when
+	 * any child cgroups exist. This is theoretically supportable
+	 * but involves complex error handling, so it's being left until
+	 * later */
+	if (root->number_of_cgroups > 1)
+		return -EBUSY;
+
+	/* Process each subsystem */
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+		struct cgroup_subsys *ss = subsys[i];
+		unsigned long bit = 1UL << i;
+		if (bit & added_bits) {
+			/* We're binding this subsystem to this hierarchy */
+			BUG_ON(ss == NULL);
+			BUG_ON(cgrp->subsys[i]);
+			BUG_ON(!dummytop->subsys[i]);
+			BUG_ON(dummytop->subsys[i]->cgroup != dummytop);
+			mutex_lock(&ss->hierarchy_mutex);
+			cgrp->subsys[i] = dummytop->subsys[i];
+			cgrp->subsys[i]->cgroup = cgrp;
+			list_move(&ss->sibling, &root->subsys_list);
+			ss->root = root;
+			if (ss->bind)
+				ss->bind(ss, cgrp);
+			mutex_unlock(&ss->hierarchy_mutex);
+			/* refcount was already taken, and we're keeping it */
+		} else if (bit & removed_bits) {
+			/* We're removing this subsystem */
+			BUG_ON(ss == NULL);
+			BUG_ON(cgrp->subsys[i] != dummytop->subsys[i]);
+			BUG_ON(cgrp->subsys[i]->cgroup != cgrp);
+			mutex_lock(&ss->hierarchy_mutex);
+			if (ss->bind)
+				ss->bind(ss, dummytop);
+			dummytop->subsys[i]->cgroup = dummytop;
+			cgrp->subsys[i] = NULL;
+			subsys[i]->root = &rootnode;
+			list_move(&ss->sibling, &rootnode.subsys_list);
+			mutex_unlock(&ss->hierarchy_mutex);
+			/* subsystem is now free - drop reference on module */
+			module_put(ss->module);
+		} else if (bit & final_bits) {
+			/* Subsystem state should already exist */
+			BUG_ON(ss == NULL);
+			BUG_ON(!cgrp->subsys[i]);
+			/*
+			 * a refcount was taken, but we already had one, so
+			 * drop the extra reference.
+			 */
+			module_put(ss->module);
+#ifdef CONFIG_MODULE_UNLOAD
+			BUG_ON(ss->module && !module_refcount(ss->module));
+#endif
+		} else {
+			/* Subsystem state shouldn't exist */
+			BUG_ON(cgrp->subsys[i]);
+		}
+	}
+	root->subsys_bits = root->actual_subsys_bits = final_bits;
+	synchronize_rcu();
+
+	return 0;
+}
+
+static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry)
+{
+	struct cgroupfs_root *root = dentry->d_sb->s_fs_info;
+	struct cgroup_subsys *ss;
+
+	mutex_lock(&cgroup_root_mutex);
+	for_each_subsys(root, ss)
+		seq_printf(seq, ",%s", ss->name);
+	if (test_bit(ROOT_NOPREFIX, &root->flags))
+		seq_puts(seq, ",noprefix");
+	if (strlen(root->release_agent_path))
+		seq_printf(seq, ",release_agent=%s", root->release_agent_path);
+	if (clone_children(&root->top_cgroup))
+		seq_puts(seq, ",clone_children");
+	if (strlen(root->name))
+		seq_printf(seq, ",name=%s", root->name);
+	mutex_unlock(&cgroup_root_mutex);
+	return 0;
+}
+
+struct cgroup_sb_opts {
+	unsigned long subsys_bits;
+	unsigned long flags;
+	char *release_agent;
+	bool clone_children;
+	char *name;
+	/* User explicitly requested empty subsystem */
+	bool none;
+
+	struct cgroupfs_root *new_root;
+
+};
+
+/*
+ * Convert a hierarchy specifier into a bitmask of subsystems and flags. Call
+ * with cgroup_mutex held to protect the subsys[] array. This function takes
+ * refcounts on subsystems to be used, unless it returns error, in which case
+ * no refcounts are taken.
+ */
+static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
+{
+	char *token, *o = data;
+	bool all_ss = false, one_ss = false;
+	unsigned long mask = (unsigned long)-1;
+	int i;
+	bool module_pin_failed = false;
+
+	BUG_ON(!mutex_is_locked(&cgroup_mutex));
+
+#ifdef CONFIG_CPUSETS
+	mask = ~(1UL << cpuset_subsys_id);
+#endif
+
+	memset(opts, 0, sizeof(*opts));
+
+	while ((token = strsep(&o, ",")) != NULL) {
+		if (!*token)
+			return -EINVAL;
+		if (!strcmp(token, "none")) {
+			/* Explicitly have no subsystems */
+			opts->none = true;
+			continue;
+		}
+		if (!strcmp(token, "all")) {
+			/* Mutually exclusive option 'all' + subsystem name */
+			if (one_ss)
+				return -EINVAL;
+			all_ss = true;
+			continue;
+		}
+		if (!strcmp(token, "noprefix")) {
+			set_bit(ROOT_NOPREFIX, &opts->flags);
+			continue;
+		}
+		if (!strcmp(token, "clone_children")) {
+			opts->clone_children = true;
+			continue;
+		}
+		if (!strncmp(token, "release_agent=", 14)) {
+			/* Specifying two release agents is forbidden */
+			if (opts->release_agent)
+				return -EINVAL;
+			opts->release_agent =
+				kstrndup(token + 14, PATH_MAX - 1, GFP_KERNEL);
+			if (!opts->release_agent)
+				return -ENOMEM;
+			continue;
+		}
+		if (!strncmp(token, "name=", 5)) {
+			const char *name = token + 5;
+			/* Can't specify an empty name */
+			if (!strlen(name))
+				return -EINVAL;
+			/* Must match [\w.-]+ */
+			for (i = 0; i < strlen(name); i++) {
+				char c = name[i];
+				if (isalnum(c))
+					continue;
+				if ((c == '.') || (c == '-') || (c == '_'))
+					continue;
+				return -EINVAL;
+			}
+			/* Specifying two names is forbidden */
+			if (opts->name)
+				return -EINVAL;
+			opts->name = kstrndup(name,
+					      MAX_CGROUP_ROOT_NAMELEN - 1,
+					      GFP_KERNEL);
+			if (!opts->name)
+				return -ENOMEM;
+
+			continue;
+		}
+
+		for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+			struct cgroup_subsys *ss = subsys[i];
+			if (ss == NULL)
+				continue;
+			if (strcmp(token, ss->name))
+				continue;
+			if (ss->disabled)
+				continue;
+
+			/* Mutually exclusive option 'all' + subsystem name */
+			if (all_ss)
+				return -EINVAL;
+			set_bit(i, &opts->subsys_bits);
+			one_ss = true;
+
+			break;
+		}
+		if (i == CGROUP_SUBSYS_COUNT)
+			return -ENOENT;
+	}
+
+	/*
+	 * If the 'all' option was specified select all the subsystems,
+	 * otherwise if 'none', 'name=' and a subsystem name options
+	 * were not specified, let's default to 'all'
+	 */
+	if (all_ss || (!one_ss && !opts->none && !opts->name)) {
+		for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+			struct cgroup_subsys *ss = subsys[i];
+			if (ss == NULL)
+				continue;
+			if (ss->disabled)
+				continue;
+			set_bit(i, &opts->subsys_bits);
+		}
+	}
+
+	/* Consistency checks */
+
+	/*
+	 * Option noprefix was introduced just for backward compatibility
+	 * with the old cpuset, so we allow noprefix only if mounting just
+	 * the cpuset subsystem.
+	 */
+	if (test_bit(ROOT_NOPREFIX, &opts->flags) &&
+	    (opts->subsys_bits & mask))
+		return -EINVAL;
+
+
+	/* Can't specify "none" and some subsystems */
+	if (opts->subsys_bits && opts->none)
+		return -EINVAL;
+
+	/*
+	 * We either have to specify by name or by subsystems. (So all
+	 * empty hierarchies must have a name).
+	 */
+	if (!opts->subsys_bits && !opts->name)
+		return -EINVAL;
+
+	/*
+	 * Grab references on all the modules we'll need, so the subsystems
+	 * don't dance around before rebind_subsystems attaches them. This may
+	 * take duplicate reference counts on a subsystem that's already used,
+	 * but rebind_subsystems handles this case.
+	 */
+	for (i = CGROUP_BUILTIN_SUBSYS_COUNT; i < CGROUP_SUBSYS_COUNT; i++) {
+		unsigned long bit = 1UL << i;
+
+		if (!(bit & opts->subsys_bits))
+			continue;
+		if (!try_module_get(subsys[i]->module)) {
+			module_pin_failed = true;
+			break;
+		}
+	}
+	if (module_pin_failed) {
+		/*
+		 * oops, one of the modules was going away. this means that we
+		 * raced with a module_delete call, and to the user this is
+		 * essentially a "subsystem doesn't exist" case.
+		 */
+		for (i--; i >= CGROUP_BUILTIN_SUBSYS_COUNT; i--) {
+			/* drop refcounts only on the ones we took */
+			unsigned long bit = 1UL << i;
+
+			if (!(bit & opts->subsys_bits))
+				continue;
+			module_put(subsys[i]->module);
+		}
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+static void drop_parsed_module_refcounts(unsigned long subsys_bits)
+{
+	int i;
+	for (i = CGROUP_BUILTIN_SUBSYS_COUNT; i < CGROUP_SUBSYS_COUNT; i++) {
+		unsigned long bit = 1UL << i;
+
+		if (!(bit & subsys_bits))
+			continue;
+		module_put(subsys[i]->module);
+	}
+}
+
+static int cgroup_remount(struct super_block *sb, int *flags, char *data)
+{
+	int ret = 0;
+	struct cgroupfs_root *root = sb->s_fs_info;
+	struct cgroup *cgrp = &root->top_cgroup;
+	struct cgroup_sb_opts opts;
+
+	mutex_lock(&cgrp->dentry->d_inode->i_mutex);
+	mutex_lock(&cgroup_mutex);
+	mutex_lock(&cgroup_root_mutex);
+
+	/* See what subsystems are wanted */
+	ret = parse_cgroupfs_options(data, &opts);
+	if (ret)
+		goto out_unlock;
+
+	/* Don't allow flags or name to change at remount */
+	if (opts.flags != root->flags ||
+	    (opts.name && strcmp(opts.name, root->name))) {
+		ret = -EINVAL;
+		drop_parsed_module_refcounts(opts.subsys_bits);
+		goto out_unlock;
+	}
+
+	ret = rebind_subsystems(root, opts.subsys_bits);
+	if (ret) {
+		drop_parsed_module_refcounts(opts.subsys_bits);
+		goto out_unlock;
+	}
+
+	/* (re)populate subsystem files */
+	cgroup_populate_dir(cgrp);
+
+	if (opts.release_agent)
+		strcpy(root->release_agent_path, opts.release_agent);
+ out_unlock:
+	kfree(opts.release_agent);
+	kfree(opts.name);
+	mutex_unlock(&cgroup_root_mutex);
+	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
+	return ret;
+}
+
+static const struct super_operations cgroup_ops = {
+	.statfs = simple_statfs,
+	.drop_inode = generic_delete_inode,
+	.show_options = cgroup_show_options,
+	.remount_fs = cgroup_remount,
+};
+
+static void init_cgroup_housekeeping(struct cgroup *cgrp)
+{
+	INIT_LIST_HEAD(&cgrp->sibling);
+	INIT_LIST_HEAD(&cgrp->children);
+	INIT_LIST_HEAD(&cgrp->css_sets);
+	INIT_LIST_HEAD(&cgrp->release_list);
+	INIT_LIST_HEAD(&cgrp->pidlists);
+	mutex_init(&cgrp->pidlist_mutex);
+	INIT_LIST_HEAD(&cgrp->event_list);
+	spin_lock_init(&cgrp->event_list_lock);
+}
+
+static void init_cgroup_root(struct cgroupfs_root *root)
+{
+	struct cgroup *cgrp = &root->top_cgroup;
+	INIT_LIST_HEAD(&root->subsys_list);
+	INIT_LIST_HEAD(&root->root_list);
+	root->number_of_cgroups = 1;
+	cgrp->root = root;
+	cgrp->top_cgroup = cgrp;
+	init_cgroup_housekeeping(cgrp);
+}
+
+static bool init_root_id(struct cgroupfs_root *root)
+{
+	int ret = 0;
+
+	do {
+		if (!ida_pre_get(&hierarchy_ida, GFP_KERNEL))
+			return false;
+		spin_lock(&hierarchy_id_lock);
+		/* Try to allocate the next unused ID */
+		ret = ida_get_new_above(&hierarchy_ida, next_hierarchy_id,
+					&root->hierarchy_id);
+		if (ret == -ENOSPC)
+			/* Try again starting from 0 */
+			ret = ida_get_new(&hierarchy_ida, &root->hierarchy_id);
+		if (!ret) {
+			next_hierarchy_id = root->hierarchy_id + 1;
+		} else if (ret != -EAGAIN) {
+			/* Can only get here if the 31-bit IDR is full ... */
+			BUG_ON(ret);
+		}
+		spin_unlock(&hierarchy_id_lock);
+	} while (ret);
+	return true;
+}
+
+static int cgroup_test_super(struct super_block *sb, void *data)
+{
+	struct cgroup_sb_opts *opts = data;
+	struct cgroupfs_root *root = sb->s_fs_info;
+
+	/* If we asked for a name then it must match */
+	if (opts->name && strcmp(opts->name, root->name))
+		return 0;
+
+	/*
+	 * If we asked for subsystems (or explicitly for no
+	 * subsystems) then they must match
+	 */
+	if ((opts->subsys_bits || opts->none)
+	    && (opts->subsys_bits != root->subsys_bits))
+		return 0;
+
+	return 1;
+}
+
+static struct cgroupfs_root *cgroup_root_from_opts(struct cgroup_sb_opts *opts)
+{
+	struct cgroupfs_root *root;
+
+	if (!opts->subsys_bits && !opts->none)
+		return NULL;
+
+	root = kzalloc(sizeof(*root), GFP_KERNEL);
+	if (!root)
+		return ERR_PTR(-ENOMEM);
+
+	if (!init_root_id(root)) {
+		kfree(root);
+		return ERR_PTR(-ENOMEM);
+	}
+	init_cgroup_root(root);
+
+	root->subsys_bits = opts->subsys_bits;
+	root->flags = opts->flags;
+	if (opts->release_agent)
+		strcpy(root->release_agent_path, opts->release_agent);
+	if (opts->name)
+		strcpy(root->name, opts->name);
+	if (opts->clone_children)
+		set_bit(CGRP_CLONE_CHILDREN, &root->top_cgroup.flags);
+	return root;
+}
+
+static void cgroup_drop_root(struct cgroupfs_root *root)
+{
+	if (!root)
+		return;
+
+	BUG_ON(!root->hierarchy_id);
+	spin_lock(&hierarchy_id_lock);
+	ida_remove(&hierarchy_ida, root->hierarchy_id);
+	spin_unlock(&hierarchy_id_lock);
+	kfree(root);
+}
+
+static int cgroup_set_super(struct super_block *sb, void *data)
+{
+	int ret;
+	struct cgroup_sb_opts *opts = data;
+
+	/* If we don't have a new root, we can't set up a new sb */
+	if (!opts->new_root)
+		return -EINVAL;
+
+	BUG_ON(!opts->subsys_bits && !opts->none);
+
+	ret = set_anon_super(sb, NULL);
+	if (ret)
+		return ret;
+
+	sb->s_fs_info = opts->new_root;
+	opts->new_root->sb = sb;
+
+	sb->s_blocksize = PAGE_CACHE_SIZE;
+	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+	sb->s_magic = CGROUP_SUPER_MAGIC;
+	sb->s_op = &cgroup_ops;
+
+	return 0;
+}
+
+static int cgroup_get_rootdir(struct super_block *sb)
+{
+	static const struct dentry_operations cgroup_dops = {
+		.d_iput = cgroup_diput,
+		.d_delete = cgroup_delete,
+	};
+
+	struct inode *inode =
+		cgroup_new_inode(S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR, sb);
+	struct dentry *dentry;
+
+	if (!inode)
+		return -ENOMEM;
+
+	inode->i_fop = &simple_dir_operations;
+	inode->i_op = &cgroup_dir_inode_operations;
+	/* directories start off with i_nlink == 2 (for "." entry) */
+	inc_nlink(inode);
+	dentry = d_alloc_root(inode);
+	if (!dentry) {
+		iput(inode);
+		return -ENOMEM;
+	}
+	sb->s_root = dentry;
+	/* for everything else we want ->d_op set */
+	sb->s_d_op = &cgroup_dops;
+	return 0;
+}
+
+static struct dentry *cgroup_mount(struct file_system_type *fs_type,
+			 int flags, const char *unused_dev_name,
+			 void *data)
+{
+	struct cgroup_sb_opts opts;
+	struct cgroupfs_root *root;
+	int ret = 0;
+	struct super_block *sb;
+	struct cgroupfs_root *new_root;
+	struct inode *inode;
+
+	/* First find the desired set of subsystems */
+	mutex_lock(&cgroup_mutex);
+	ret = parse_cgroupfs_options(data, &opts);
+	mutex_unlock(&cgroup_mutex);
+	if (ret)
+		goto out_err;
+
+	/*
+	 * Allocate a new cgroup root. We may not need it if we're
+	 * reusing an existing hierarchy.
+	 */
+	new_root = cgroup_root_from_opts(&opts);
+	if (IS_ERR(new_root)) {
+		ret = PTR_ERR(new_root);
+		goto drop_modules;
+	}
+	opts.new_root = new_root;
+
+	/* Locate an existing or new sb for this hierarchy */
+	sb = sget(fs_type, cgroup_test_super, cgroup_set_super, &opts);
+	if (IS_ERR(sb)) {
+		ret = PTR_ERR(sb);
+		cgroup_drop_root(opts.new_root);
+		goto drop_modules;
+	}
+
+	root = sb->s_fs_info;
+	BUG_ON(!root);
+	if (root == opts.new_root) {
+		/* We used the new root structure, so this is a new hierarchy */
+		struct list_head tmp_cg_links;
+		struct cgroup *root_cgrp = &root->top_cgroup;
+		struct cgroupfs_root *existing_root;
+		const struct cred *cred;
+		int i;
+
+		BUG_ON(sb->s_root != NULL);
+
+		ret = cgroup_get_rootdir(sb);
+		if (ret)
+			goto drop_new_super;
+		inode = sb->s_root->d_inode;
+
+		mutex_lock(&inode->i_mutex);
+		mutex_lock(&cgroup_mutex);
+		mutex_lock(&cgroup_root_mutex);
+
+		/* Check for name clashes with existing mounts */
+		ret = -EBUSY;
+		if (strlen(root->name))
+			for_each_active_root(existing_root)
+				if (!strcmp(existing_root->name, root->name))
+					goto unlock_drop;
+
+		/*
+		 * We're accessing css_set_count without locking
+		 * css_set_lock here, but that's OK - it can only be
+		 * increased by someone holding cgroup_lock, and
+		 * that's us. The worst that can happen is that we
+		 * have some link structures left over
+		 */
+		ret = allocate_cg_links(css_set_count, &tmp_cg_links);
+		if (ret)
+			goto unlock_drop;
+
+		ret = rebind_subsystems(root, root->subsys_bits);
+		if (ret == -EBUSY) {
+			free_cg_links(&tmp_cg_links);
+			goto unlock_drop;
+		}
+		/*
+		 * There must be no failure case after here, since rebinding
+		 * takes care of subsystems' refcounts, which are explicitly
+		 * dropped in the failure exit path.
+		 */
+
+		/* EBUSY should be the only error here */
+		BUG_ON(ret);
+
+		list_add(&root->root_list, &roots);
+		root_count++;
+
+		sb->s_root->d_fsdata = root_cgrp;
+		root->top_cgroup.dentry = sb->s_root;
+
+		/* Link the top cgroup in this hierarchy into all
+		 * the css_set objects */
+		write_lock(&css_set_lock);
+		for (i = 0; i < CSS_SET_TABLE_SIZE; i++) {
+			struct hlist_head *hhead = &css_set_table[i];
+			struct hlist_node *node;
+			struct css_set *cg;
+
+			hlist_for_each_entry(cg, node, hhead, hlist)
+				link_css_set(&tmp_cg_links, cg, root_cgrp);
+		}
+		write_unlock(&css_set_lock);
+
+		free_cg_links(&tmp_cg_links);
+
+		BUG_ON(!list_empty(&root_cgrp->sibling));
+		BUG_ON(!list_empty(&root_cgrp->children));
+		BUG_ON(root->number_of_cgroups != 1);
+
+		cred = override_creds(&init_cred);
+		cgroup_populate_dir(root_cgrp);
+		revert_creds(cred);
+		mutex_unlock(&cgroup_root_mutex);
+		mutex_unlock(&cgroup_mutex);
+		mutex_unlock(&inode->i_mutex);
+	} else {
+		/*
+		 * We re-used an existing hierarchy - the new root (if
+		 * any) is not needed
+		 */
+		cgroup_drop_root(opts.new_root);
+		/* no subsys rebinding, so refcounts don't change */
+		drop_parsed_module_refcounts(opts.subsys_bits);
+	}
+
+	kfree(opts.release_agent);
+	kfree(opts.name);
+	return dget(sb->s_root);
+
+ unlock_drop:
+	mutex_unlock(&cgroup_root_mutex);
+	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&inode->i_mutex);
+ drop_new_super:
+	deactivate_locked_super(sb);
+ drop_modules:
+	drop_parsed_module_refcounts(opts.subsys_bits);
+ out_err:
+	kfree(opts.release_agent);
+	kfree(opts.name);
+	return ERR_PTR(ret);
+}
+
+static void cgroup_kill_sb(struct super_block *sb) {
+	struct cgroupfs_root *root = sb->s_fs_info;
+	struct cgroup *cgrp = &root->top_cgroup;
+	int ret;
+	struct cg_cgroup_link *link;
+	struct cg_cgroup_link *saved_link;
+
+	BUG_ON(!root);
+
+	BUG_ON(root->number_of_cgroups != 1);
+	BUG_ON(!list_empty(&cgrp->children));
+	BUG_ON(!list_empty(&cgrp->sibling));
+
+	mutex_lock(&cgroup_mutex);
+	mutex_lock(&cgroup_root_mutex);
+
+	/* Rebind all subsystems back to the default hierarchy */
+	ret = rebind_subsystems(root, 0);
+	/* Shouldn't be able to fail ... */
+	BUG_ON(ret);
+
+	/*
+	 * Release all the links from css_sets to this hierarchy's
+	 * root cgroup
+	 */
+	write_lock(&css_set_lock);
+
+	list_for_each_entry_safe(link, saved_link, &cgrp->css_sets,
+				 cgrp_link_list) {
+		list_del(&link->cg_link_list);
+		list_del(&link->cgrp_link_list);
+		kfree(link);
+	}
+	write_unlock(&css_set_lock);
+
+	if (!list_empty(&root->root_list)) {
+		list_del(&root->root_list);
+		root_count--;
+	}
+
+	mutex_unlock(&cgroup_root_mutex);
+	mutex_unlock(&cgroup_mutex);
+
+	kill_litter_super(sb);
+	cgroup_drop_root(root);
+}
+
+static struct file_system_type cgroup_fs_type = {
+	.name = "cgroup",
+	.mount = cgroup_mount,
+	.kill_sb = cgroup_kill_sb,
+};
+
+static struct kobject *cgroup_kobj;
+
+static inline struct cgroup *__d_cgrp(struct dentry *dentry)
+{
+	return dentry->d_fsdata;
+}
+
+static inline struct cftype *__d_cft(struct dentry *dentry)
+{
+	return dentry->d_fsdata;
+}
+
+/**
+ * cgroup_path - generate the path of a cgroup
+ * @cgrp: the cgroup in question
+ * @buf: the buffer to write the path into
+ * @buflen: the length of the buffer
+ *
+ * Called with cgroup_mutex held or else with an RCU-protected cgroup
+ * reference.  Writes path of cgroup into buf.  Returns 0 on success,
+ * -errno on error.
+ */
+int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen)
+{
+	char *start;
+	struct dentry *dentry = rcu_dereference_check(cgrp->dentry,
+						      cgroup_lock_is_held());
+
+	if (!dentry || cgrp == dummytop) {
+		/*
+		 * Inactive subsystems have no dentry for their root
+		 * cgroup
+		 */
+		strcpy(buf, "/");
+		return 0;
+	}
+
+	start = buf + buflen;
+
+	*--start = '\0';
+	for (;;) {
+		int len = dentry->d_name.len;
+
+		if ((start -= len) < buf)
+			return -ENAMETOOLONG;
+		memcpy(start, dentry->d_name.name, len);
+		cgrp = cgrp->parent;
+		if (!cgrp)
+			break;
+
+		dentry = rcu_dereference_check(cgrp->dentry,
+					       cgroup_lock_is_held());
+		if (!cgrp->parent)
+			continue;
+		if (--start < buf)
+			return -ENAMETOOLONG;
+		*start = '/';
+	}
+	memmove(buf, start, buf + buflen - start);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cgroup_path);
+
+/*
+ * Control Group taskset
+ */
+struct task_and_cgroup {
+	struct task_struct	*task;
+	struct cgroup		*cgrp;
+};
+
+struct cgroup_taskset {
+	struct task_and_cgroup	single;
+	struct flex_array	*tc_array;
+	int			tc_array_len;
+	int			idx;
+	struct cgroup		*cur_cgrp;
+};
+
+/**
+ * cgroup_taskset_first - reset taskset and return the first task
+ * @tset: taskset of interest
+ *
+ * @tset iteration is initialized and the first task is returned.
+ */
+struct task_struct *cgroup_taskset_first(struct cgroup_taskset *tset)
+{
+	if (tset->tc_array) {
+		tset->idx = 0;
+		return cgroup_taskset_next(tset);
+	} else {
+		tset->cur_cgrp = tset->single.cgrp;
+		return tset->single.task;
+	}
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_first);
+
+/**
+ * cgroup_taskset_next - iterate to the next task in taskset
+ * @tset: taskset of interest
+ *
+ * Return the next task in @tset.  Iteration must have been initialized
+ * with cgroup_taskset_first().
+ */
+struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset)
+{
+	struct task_and_cgroup *tc;
+
+	if (!tset->tc_array || tset->idx >= tset->tc_array_len)
+		return NULL;
+
+	tc = flex_array_get(tset->tc_array, tset->idx++);
+	tset->cur_cgrp = tc->cgrp;
+	return tc->task;
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_next);
+
+/**
+ * cgroup_taskset_cur_cgroup - return the matching cgroup for the current task
+ * @tset: taskset of interest
+ *
+ * Return the cgroup for the current (last returned) task of @tset.  This
+ * function must be preceded by either cgroup_taskset_first() or
+ * cgroup_taskset_next().
+ */
+struct cgroup *cgroup_taskset_cur_cgroup(struct cgroup_taskset *tset)
+{
+	return tset->cur_cgrp;
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_cur_cgroup);
+
+/**
+ * cgroup_taskset_size - return the number of tasks in taskset
+ * @tset: taskset of interest
+ */
+int cgroup_taskset_size(struct cgroup_taskset *tset)
+{
+	return tset->tc_array ? tset->tc_array_len : 1;
+}
+EXPORT_SYMBOL_GPL(cgroup_taskset_size);
+
+
+/*
+ * cgroup_task_migrate - move a task from one cgroup to another.
+ *
+ * 'guarantee' is set if the caller promises that a new css_set for the task
+ * will already exist. If not set, this function might sleep, and can fail with
+ * -ENOMEM. Must be called with cgroup_mutex and threadgroup locked.
+ */
+static int cgroup_task_migrate(struct cgroup *cgrp, struct cgroup *oldcgrp,
+			       struct task_struct *tsk, bool guarantee)
+{
+	struct css_set *oldcg;
+	struct css_set *newcg;
+
+	/*
+	 * We are synchronized through threadgroup_lock() against PF_EXITING
+	 * setting such that we can't race against cgroup_exit() changing the
+	 * css_set to init_css_set and dropping the old one.
+	 */
+	WARN_ON_ONCE(tsk->flags & PF_EXITING);
+	oldcg = tsk->cgroups;
+
+	/* locate or allocate a new css_set for this task. */
+	if (guarantee) {
+		/* we know the css_set we want already exists. */
+		struct cgroup_subsys_state *template[CGROUP_SUBSYS_COUNT];
+		read_lock(&css_set_lock);
+		newcg = find_existing_css_set(oldcg, cgrp, template);
+		BUG_ON(!newcg);
+		get_css_set(newcg);
+		read_unlock(&css_set_lock);
+	} else {
+		might_sleep();
+		/* find_css_set will give us newcg already referenced. */
+		newcg = find_css_set(oldcg, cgrp);
+		if (!newcg)
+			return -ENOMEM;
+	}
+
+	task_lock(tsk);
+	rcu_assign_pointer(tsk->cgroups, newcg);
+	task_unlock(tsk);
+
+	/* Update the css_set linked lists if we're using them */
+	write_lock(&css_set_lock);
+	if (!list_empty(&tsk->cg_list))
+		list_move(&tsk->cg_list, &newcg->tasks);
+	write_unlock(&css_set_lock);
+
+	/*
+	 * We just gained a reference on oldcg by taking it from the task. As
+	 * trading it for newcg is protected by cgroup_mutex, we're safe to drop
+	 * it here; it will be freed under RCU.
+	 */
+	put_css_set(oldcg);
+
+	set_bit(CGRP_RELEASABLE, &oldcgrp->flags);
+	return 0;
+}
+
+/**
+ * cgroup_attach_task - attach task 'tsk' to cgroup 'cgrp'
+ * @cgrp: the cgroup the task is attaching to
+ * @tsk: the task to be attached
+ *
+ * Call with cgroup_mutex and threadgroup locked. May take task_lock of
+ * @tsk during call.
+ */
+int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk)
+{
+	int retval;
+	struct cgroup_subsys *ss, *failed_ss = NULL;
+	struct cgroup *oldcgrp;
+	struct cgroupfs_root *root = cgrp->root;
+	struct cgroup_taskset tset = { };
+
+	/* @tsk either already exited or can't exit until the end */
+	if (tsk->flags & PF_EXITING)
+		return -ESRCH;
+
+	/* Nothing to do if the task is already in that cgroup */
+	oldcgrp = task_cgroup_from_root(tsk, root);
+	if (cgrp == oldcgrp)
+		return 0;
+
+	tset.single.task = tsk;
+	tset.single.cgrp = oldcgrp;
+
+	for_each_subsys(root, ss) {
+		if (ss->can_attach) {
+			retval = ss->can_attach(ss, cgrp, &tset);
+			if (retval) {
+				/*
+				 * Remember on which subsystem the can_attach()
+				 * failed, so that we only call cancel_attach()
+				 * against the subsystems whose can_attach()
+				 * succeeded. (See below)
+				 */
+				failed_ss = ss;
+				goto out;
+			}
+		}
+	}
+
+	retval = cgroup_task_migrate(cgrp, oldcgrp, tsk, false);
+	if (retval)
+		goto out;
+
+	for_each_subsys(root, ss) {
+		if (ss->attach)
+			ss->attach(ss, cgrp, &tset);
+	}
+
+	synchronize_rcu();
+
+	/*
+	 * wake up rmdir() waiter. the rmdir should fail since the cgroup
+	 * is no longer empty.
+	 */
+	cgroup_wakeup_rmdir_waiter(cgrp);
+out:
+	if (retval) {
+		for_each_subsys(root, ss) {
+			if (ss == failed_ss)
+				/*
+				 * This subsystem was the one that failed the
+				 * can_attach() check earlier, so we don't need
+				 * to call cancel_attach() against it or any
+				 * remaining subsystems.
+				 */
+				break;
+			if (ss->cancel_attach)
+				ss->cancel_attach(ss, cgrp, &tset);
+		}
+	}
+	return retval;
+}
+
+/**
+ * cgroup_attach_task_all - attach task 'tsk' to all cgroups of task 'from'
+ * @from: attach to all cgroups of a given task
+ * @tsk: the task to be attached
+ */
+int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk)
+{
+	struct cgroupfs_root *root;
+	int retval = 0;
+
+	cgroup_lock();
+	for_each_active_root(root) {
+		struct cgroup *from_cg = task_cgroup_from_root(from, root);
+
+		retval = cgroup_attach_task(from_cg, tsk);
+		if (retval)
+			break;
+	}
+	cgroup_unlock();
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(cgroup_attach_task_all);
+
+/*
+ * cgroup_attach_proc works in two stages, the first of which prefetches all
+ * new css_sets needed (to make sure we have enough memory before committing
+ * to the move) and stores them in a list of entries of the following type.
+ * TODO: possible optimization: use css_set->rcu_head for chaining instead
+ */
+struct cg_list_entry {
+	struct css_set *cg;
+	struct list_head links;
+};
+
+static bool css_set_check_fetched(struct cgroup *cgrp,
+				  struct task_struct *tsk, struct css_set *cg,
+				  struct list_head *newcg_list)
+{
+	struct css_set *newcg;
+	struct cg_list_entry *cg_entry;
+	struct cgroup_subsys_state *template[CGROUP_SUBSYS_COUNT];
+
+	read_lock(&css_set_lock);
+	newcg = find_existing_css_set(cg, cgrp, template);
+	read_unlock(&css_set_lock);
+
+	/* doesn't exist at all? */
+	if (!newcg)
+		return false;
+	/* see if it's already in the list */
+	list_for_each_entry(cg_entry, newcg_list, links)
+		if (cg_entry->cg == newcg)
+			return true;
+
+	/* not found */
+	return false;
+}
+
+/*
+ * Find the new css_set and store it in the list in preparation for moving the
+ * given task to the given cgroup. Returns 0 or -ENOMEM.
+ */
+static int css_set_prefetch(struct cgroup *cgrp, struct css_set *cg,
+			    struct list_head *newcg_list)
+{
+	struct css_set *newcg;
+	struct cg_list_entry *cg_entry;
+
+	/* ensure a new css_set will exist for this thread */
+	newcg = find_css_set(cg, cgrp);
+	if (!newcg)
+		return -ENOMEM;
+	/* add it to the list */
+	cg_entry = kmalloc(sizeof(struct cg_list_entry), GFP_KERNEL);
+	if (!cg_entry) {
+		put_css_set(newcg);
+		return -ENOMEM;
+	}
+	cg_entry->cg = newcg;
+	list_add(&cg_entry->links, newcg_list);
+	return 0;
+}
+
+/**
+ * cgroup_attach_proc - attach all threads in a threadgroup to a cgroup
+ * @cgrp: the cgroup to attach to
+ * @leader: the threadgroup leader task_struct of the group to be attached
+ *
+ * Call holding cgroup_mutex and the group_rwsem of the leader. Will take
+ * task_lock of each thread in leader's threadgroup individually in turn.
+ */
+static int cgroup_attach_proc(struct cgroup *cgrp, struct task_struct *leader)
+{
+	int retval, i, group_size;
+	struct cgroup_subsys *ss, *failed_ss = NULL;
+	/* guaranteed to be initialized later, but the compiler needs this */
+	struct css_set *oldcg;
+	struct cgroupfs_root *root = cgrp->root;
+	/* threadgroup list cursor and array */
+	struct task_struct *tsk;
+	struct task_and_cgroup *tc;
+	struct flex_array *group;
+	struct cgroup_taskset tset = { };
+	/*
+	 * we need to make sure we have css_sets for all the tasks we're
+	 * going to move -before- we actually start moving them, so that in
+	 * case we get an ENOMEM we can bail out before making any changes.
+	 */
+	struct list_head newcg_list;
+	struct cg_list_entry *cg_entry, *temp_nobe;
+
+	/*
+	 * step 0: in order to do expensive, possibly blocking operations for
+	 * every thread, we cannot iterate the thread group list, since it needs
+	 * rcu or tasklist locked. instead, build an array of all threads in the
+	 * group - group_rwsem prevents new threads from appearing, and if
+	 * threads exit, this will just be an over-estimate.
+	 */
+	group_size = get_nr_threads(leader);
+	/* flex_array supports very large thread-groups better than kmalloc. */
+	group = flex_array_alloc(sizeof(*tc), group_size, GFP_KERNEL);
+	if (!group)
+		return -ENOMEM;
+	/* pre-allocate to guarantee space while iterating in rcu read-side. */
+	retval = flex_array_prealloc(group, 0, group_size - 1, GFP_KERNEL);
+	if (retval)
+		goto out_free_group_list;
+
+	/* prevent changes to the threadgroup list while we take a snapshot. */
+	read_lock(&tasklist_lock);
+	if (!thread_group_leader(leader)) {
+		/*
+		 * a race with de_thread from another thread's exec() may strip
+		 * us of our leadership, making while_each_thread unsafe to use
+		 * on this task. if this happens, there is no choice but to
+		 * throw this task away and try again (from cgroup_procs_write);
+		 * this is "double-double-toil-and-trouble-check locking".
+		 */
+		read_unlock(&tasklist_lock);
+		retval = -EAGAIN;
+		goto out_free_group_list;
+	}
+
+	tsk = leader;
+	i = 0;
+	do {
+		struct task_and_cgroup ent;
+
+		/* @tsk either already exited or can't exit until the end */
+		if (tsk->flags & PF_EXITING)
+			continue;
+
+		/* as per above, nr_threads may decrease, but not increase. */
+		BUG_ON(i >= group_size);
+		/*
+		 * saying GFP_ATOMIC has no effect here because we did prealloc
+		 * earlier, but it's good form to communicate our expectations.
+		 */
+		ent.task = tsk;
+		ent.cgrp = task_cgroup_from_root(tsk, root);
+		/* nothing to do if this task is already in the cgroup */
+		if (ent.cgrp == cgrp)
+			continue;
+		retval = flex_array_put(group, i, &ent, GFP_ATOMIC);
+		BUG_ON(retval != 0);
+		i++;
+	} while_each_thread(leader, tsk);
+	/* remember the number of threads in the array for later. */
+	group_size = i;
+	tset.tc_array = group;
+	tset.tc_array_len = group_size;
+	read_unlock(&tasklist_lock);
+
+	/* methods shouldn't be called if no task is actually migrating */
+	retval = 0;
+	if (!group_size)
+		goto out_free_group_list;
+
+	/*
+	 * step 1: check that we can legitimately attach to the cgroup.
+	 */
+	for_each_subsys(root, ss) {
+		if (ss->can_attach) {
+			retval = ss->can_attach(ss, cgrp, &tset);
+			if (retval) {
+				failed_ss = ss;
+				goto out_cancel_attach;
+			}
+		}
+	}
+
+	/*
+	 * step 2: make sure css_sets exist for all threads to be migrated.
+	 * we use find_css_set, which allocates a new one if necessary.
+	 */
+	INIT_LIST_HEAD(&newcg_list);
+	for (i = 0; i < group_size; i++) {
+		tc = flex_array_get(group, i);
+		oldcg = tc->task->cgroups;
+
+		/* if we don't already have it in the list get a new one */
+		if (!css_set_check_fetched(cgrp, tc->task, oldcg,
+					   &newcg_list)) {
+			retval = css_set_prefetch(cgrp, oldcg, &newcg_list);
+			if (retval)
+				goto out_list_teardown;
+		}
+	}
+
+	/*
+	 * step 3: now that we're guaranteed success wrt the css_sets,
+	 * proceed to move all tasks to the new cgroup.  There are no
+	 * failure cases after here, so this is the commit point.
+	 */
+	for (i = 0; i < group_size; i++) {
+		tc = flex_array_get(group, i);
+		retval = cgroup_task_migrate(cgrp, tc->cgrp, tc->task, true);
+		BUG_ON(retval);
+	}
+	/* nothing is sensitive to fork() after this point. */
+
+	/*
+	 * step 4: do subsystem attach callbacks.
+	 */
+	for_each_subsys(root, ss) {
+		if (ss->attach)
+			ss->attach(ss, cgrp, &tset);
+	}
+
+	/*
+	 * step 5: success! and cleanup
+	 */
+	synchronize_rcu();
+	cgroup_wakeup_rmdir_waiter(cgrp);
+	retval = 0;
+out_list_teardown:
+	/* clean up the list of prefetched css_sets. */
+	list_for_each_entry_safe(cg_entry, temp_nobe, &newcg_list, links) {
+		list_del(&cg_entry->links);
+		put_css_set(cg_entry->cg);
+		kfree(cg_entry);
+	}
+out_cancel_attach:
+	/* same deal as in cgroup_attach_task */
+	if (retval) {
+		for_each_subsys(root, ss) {
+			if (ss == failed_ss)
+				break;
+			if (ss->cancel_attach)
+				ss->cancel_attach(ss, cgrp, &tset);
+		}
+	}
+out_free_group_list:
+	flex_array_free(group);
+	return retval;
+}
+
+/*
+ * Find the task_struct of the task to attach by vpid and pass it along to the
+ * function to attach either it or all tasks in its threadgroup. Will lock
+ * cgroup_mutex and threadgroup; may take task_lock of task.
+ */
+static int attach_task_by_pid(struct cgroup *cgrp, u64 pid, bool threadgroup)
+{
+	struct task_struct *tsk;
+	const struct cred *cred = current_cred(), *tcred;
+	int ret;
+
+	if (!cgroup_lock_live_group(cgrp))
+		return -ENODEV;
+
+	if (pid) {
+		rcu_read_lock();
+		tsk = find_task_by_vpid(pid);
+		if (!tsk) {
+			rcu_read_unlock();
+			cgroup_unlock();
+			return -ESRCH;
+		}
+		if (threadgroup) {
+			/*
+			 * RCU protects this access, since tsk was found in the
+			 * tid map. a race with de_thread may cause group_leader
+			 * to stop being the leader, but cgroup_attach_proc will
+			 * detect it later.
+			 */
+			tsk = tsk->group_leader;
+		}
+		/*
+		 * even if we're attaching all tasks in the thread group, we
+		 * only need to check permissions on one of them.
+		 */
+		tcred = __task_cred(tsk);
+		if (cred->euid &&
+		    cred->euid != tcred->uid &&
+		    cred->euid != tcred->suid) {
+			rcu_read_unlock();
+			cgroup_unlock();
+			return -EACCES;
+		}
+		get_task_struct(tsk);
+		rcu_read_unlock();
+	} else {
+		if (threadgroup)
+			tsk = current->group_leader;
+		else
+			tsk = current;
+		get_task_struct(tsk);
+	}
+
+	threadgroup_lock(tsk);
+
+	if (threadgroup)
+		ret = cgroup_attach_proc(cgrp, tsk);
+	else
+		ret = cgroup_attach_task(cgrp, tsk);
+
+	threadgroup_unlock(tsk);
+
+	put_task_struct(tsk);
+	cgroup_unlock();
+	return ret;
+}
+
+static int cgroup_tasks_write(struct cgroup *cgrp, struct cftype *cft, u64 pid)
+{
+	return attach_task_by_pid(cgrp, pid, false);
+}
+
+static int cgroup_procs_write(struct cgroup *cgrp, struct cftype *cft, u64 tgid)
+{
+	int ret;
+	do {
+		/*
+		 * attach_proc fails with -EAGAIN if threadgroup leadership
+		 * changes in the middle of the operation, in which case we need
+		 * to find the task_struct for the new leader and start over.
+		 */
+		ret = attach_task_by_pid(cgrp, tgid, true);
+	} while (ret == -EAGAIN);
+	return ret;
+}
+
+/**
+ * cgroup_lock_live_group - take cgroup_mutex and check that cgrp is alive.
+ * @cgrp: the cgroup to be checked for liveness
+ *
+ * On success, returns true; the lock should be later released with
+ * cgroup_unlock(). On failure returns false with no lock held.
+ */
+bool cgroup_lock_live_group(struct cgroup *cgrp)
+{
+	mutex_lock(&cgroup_mutex);
+	if (cgroup_is_removed(cgrp)) {
+		mutex_unlock(&cgroup_mutex);
+		return false;
+	}
+	return true;
+}
+EXPORT_SYMBOL_GPL(cgroup_lock_live_group);
+
+static int cgroup_release_agent_write(struct cgroup *cgrp, struct cftype *cft,
+				      const char *buffer)
+{
+	BUILD_BUG_ON(sizeof(cgrp->root->release_agent_path) < PATH_MAX);
+	if (strlen(buffer) >= PATH_MAX)
+		return -EINVAL;
+	if (!cgroup_lock_live_group(cgrp))
+		return -ENODEV;
+	mutex_lock(&cgroup_root_mutex);
+	strcpy(cgrp->root->release_agent_path, buffer);
+	mutex_unlock(&cgroup_root_mutex);
+	cgroup_unlock();
+	return 0;
+}
+
+static int cgroup_release_agent_show(struct cgroup *cgrp, struct cftype *cft,
+				     struct seq_file *seq)
+{
+	if (!cgroup_lock_live_group(cgrp))
+		return -ENODEV;
+	seq_puts(seq, cgrp->root->release_agent_path);
+	seq_putc(seq, '\n');
+	cgroup_unlock();
+	return 0;
+}
+
+/* A buffer size big enough for numbers or short strings */
+#define CGROUP_LOCAL_BUFFER_SIZE 64
+
+static ssize_t cgroup_write_X64(struct cgroup *cgrp, struct cftype *cft,
+				struct file *file,
+				const char __user *userbuf,
+				size_t nbytes, loff_t *unused_ppos)
+{
+	char buffer[CGROUP_LOCAL_BUFFER_SIZE];
+	int retval = 0;
+	char *end;
+
+	if (!nbytes)
+		return -EINVAL;
+	if (nbytes >= sizeof(buffer))
+		return -E2BIG;
+	if (copy_from_user(buffer, userbuf, nbytes))
+		return -EFAULT;
+
+	buffer[nbytes] = 0;     /* nul-terminate */
+	if (cft->write_u64) {
+		u64 val = simple_strtoull(strstrip(buffer), &end, 0);
+		if (*end)
+			return -EINVAL;
+		retval = cft->write_u64(cgrp, cft, val);
+	} else {
+		s64 val = simple_strtoll(strstrip(buffer), &end, 0);
+		if (*end)
+			return -EINVAL;
+		retval = cft->write_s64(cgrp, cft, val);
+	}
+	if (!retval)
+		retval = nbytes;
+	return retval;
+}
+
+static ssize_t cgroup_write_string(struct cgroup *cgrp, struct cftype *cft,
+				   struct file *file,
+				   const char __user *userbuf,
+				   size_t nbytes, loff_t *unused_ppos)
+{
+	char local_buffer[CGROUP_LOCAL_BUFFER_SIZE];
+	int retval = 0;
+	size_t max_bytes = cft->max_write_len;
+	char *buffer = local_buffer;
+
+	if (!max_bytes)
+		max_bytes = sizeof(local_buffer) - 1;
+	if (nbytes >= max_bytes)
+		return -E2BIG;
+	/* Allocate a dynamic buffer if we need one */
+	if (nbytes >= sizeof(local_buffer)) {
+		buffer = kmalloc(nbytes + 1, GFP_KERNEL);
+		if (buffer == NULL)
+			return -ENOMEM;
+	}
+	if (nbytes && copy_from_user(buffer, userbuf, nbytes)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	buffer[nbytes] = 0;     /* nul-terminate */
+	retval = cft->write_string(cgrp, cft, strstrip(buffer));
+	if (!retval)
+		retval = nbytes;
+out:
+	if (buffer != local_buffer)
+		kfree(buffer);
+	return retval;
+}
+
+static ssize_t cgroup_file_write(struct file *file, const char __user *buf,
+						size_t nbytes, loff_t *ppos)
+{
+	struct cftype *cft = __d_cft(file->f_dentry);
+	struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
+
+	if (cgroup_is_removed(cgrp))
+		return -ENODEV;
+	if (cft->write)
+		return cft->write(cgrp, cft, file, buf, nbytes, ppos);
+	if (cft->write_u64 || cft->write_s64)
+		return cgroup_write_X64(cgrp, cft, file, buf, nbytes, ppos);
+	if (cft->write_string)
+		return cgroup_write_string(cgrp, cft, file, buf, nbytes, ppos);
+	if (cft->trigger) {
+		int ret = cft->trigger(cgrp, (unsigned int)cft->private);
+		return ret ? ret : nbytes;
+	}
+	return -EINVAL;
+}
+
+static ssize_t cgroup_read_u64(struct cgroup *cgrp, struct cftype *cft,
+			       struct file *file,
+			       char __user *buf, size_t nbytes,
+			       loff_t *ppos)
+{
+	char tmp[CGROUP_LOCAL_BUFFER_SIZE];
+	u64 val = cft->read_u64(cgrp, cft);
+	int len = sprintf(tmp, "%llu\n", (unsigned long long) val);
+
+	return simple_read_from_buffer(buf, nbytes, ppos, tmp, len);
+}
+
+static ssize_t cgroup_read_s64(struct cgroup *cgrp, struct cftype *cft,
+			       struct file *file,
+			       char __user *buf, size_t nbytes,
+			       loff_t *ppos)
+{
+	char tmp[CGROUP_LOCAL_BUFFER_SIZE];
+	s64 val = cft->read_s64(cgrp, cft);
+	int len = sprintf(tmp, "%lld\n", (long long) val);
+
+	return simple_read_from_buffer(buf, nbytes, ppos, tmp, len);
+}
+
+static ssize_t cgroup_file_read(struct file *file, char __user *buf,
+				   size_t nbytes, loff_t *ppos)
+{
+	struct cftype *cft = __d_cft(file->f_dentry);
+	struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
+
+	if (cgroup_is_removed(cgrp))
+		return -ENODEV;
+
+	if (cft->read)
+		return cft->read(cgrp, cft, file, buf, nbytes, ppos);
+	if (cft->read_u64)
+		return cgroup_read_u64(cgrp, cft, file, buf, nbytes, ppos);
+	if (cft->read_s64)
+		return cgroup_read_s64(cgrp, cft, file, buf, nbytes, ppos);
+	return -EINVAL;
+}
+
+/*
+ * seqfile ops/methods for returning structured data. Currently just
+ * supports string->u64 maps, but can be extended in future.
+ */
+
+struct cgroup_seqfile_state {
+	struct cftype *cft;
+	struct cgroup *cgroup;
+};
+
+static int cgroup_map_add(struct cgroup_map_cb *cb, const char *key, u64 value)
+{
+	struct seq_file *sf = cb->state;
+	return seq_printf(sf, "%s %llu\n", key, (unsigned long long)value);
+}
+
+static int cgroup_seqfile_show(struct seq_file *m, void *arg)
+{
+	struct cgroup_seqfile_state *state = m->private;
+	struct cftype *cft = state->cft;
+	if (cft->read_map) {
+		struct cgroup_map_cb cb = {
+			.fill = cgroup_map_add,
+			.state = m,
+		};
+		return cft->read_map(state->cgroup, cft, &cb);
+	}
+	return cft->read_seq_string(state->cgroup, cft, m);
+}
+
+static int cgroup_seqfile_release(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq = file->private_data;
+	kfree(seq->private);
+	return single_release(inode, file);
+}
+
+static const struct file_operations cgroup_seqfile_operations = {
+	.read = seq_read,
+	.write = cgroup_file_write,
+	.llseek = seq_lseek,
+	.release = cgroup_seqfile_release,
+};
+
+static int cgroup_file_open(struct inode *inode, struct file *file)
+{
+	int err;
+	struct cftype *cft;
+
+	err = generic_file_open(inode, file);
+	if (err)
+		return err;
+	cft = __d_cft(file->f_dentry);
+
+	if (cft->read_map || cft->read_seq_string) {
+		struct cgroup_seqfile_state *state =
+			kzalloc(sizeof(*state), GFP_USER);
+		if (!state)
+			return -ENOMEM;
+		state->cft = cft;
+		state->cgroup = __d_cgrp(file->f_dentry->d_parent);
+		file->f_op = &cgroup_seqfile_operations;
+		err = single_open(file, cgroup_seqfile_show, state);
+		if (err < 0)
+			kfree(state);
+	} else if (cft->open)
+		err = cft->open(inode, file);
+	else
+		err = 0;
+
+	return err;
+}
+
+static int cgroup_file_release(struct inode *inode, struct file *file)
+{
+	struct cftype *cft = __d_cft(file->f_dentry);
+	if (cft->release)
+		return cft->release(inode, file);
+	return 0;
+}
+
+/*
+ * cgroup_rename - Only allow simple rename of directories in place.
+ */
+static int cgroup_rename(struct inode *old_dir, struct dentry *old_dentry,
+			    struct inode *new_dir, struct dentry *new_dentry)
+{
+	if (!S_ISDIR(old_dentry->d_inode->i_mode))
+		return -ENOTDIR;
+	if (new_dentry->d_inode)
+		return -EEXIST;
+	if (old_dir != new_dir)
+		return -EIO;
+	return simple_rename(old_dir, old_dentry, new_dir, new_dentry);
+}
+
+static const struct file_operations cgroup_file_operations = {
+	.read = cgroup_file_read,
+	.write = cgroup_file_write,
+	.llseek = generic_file_llseek,
+	.open = cgroup_file_open,
+	.release = cgroup_file_release,
+};
+
+static const struct inode_operations cgroup_dir_inode_operations = {
+	.lookup = cgroup_lookup,
+	.mkdir = cgroup_mkdir,
+	.rmdir = cgroup_rmdir,
+	.rename = cgroup_rename,
+};
+
+static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+	if (dentry->d_name.len > NAME_MAX)
+		return ERR_PTR(-ENAMETOOLONG);
+	d_add(dentry, NULL);
+	return NULL;
+}
+
+/*
+ * Check if a file is a control file
+ */
+static inline struct cftype *__file_cft(struct file *file)
+{
+	if (file->f_dentry->d_inode->i_fop != &cgroup_file_operations)
+		return ERR_PTR(-EINVAL);
+	return __d_cft(file->f_dentry);
+}
+
+static int cgroup_create_file(struct dentry *dentry, umode_t mode,
+				struct super_block *sb)
+{
+	struct inode *inode;
+
+	if (!dentry)
+		return -ENOENT;
+	if (dentry->d_inode)
+		return -EEXIST;
+
+	inode = cgroup_new_inode(mode, sb);
+	if (!inode)
+		return -ENOMEM;
+
+	if (S_ISDIR(mode)) {
+		inode->i_op = &cgroup_dir_inode_operations;
+		inode->i_fop = &simple_dir_operations;
+
+		/* start off with i_nlink == 2 (for "." entry) */
+		inc_nlink(inode);
+
+		/* start with the directory inode held, so that we can
+		 * populate it without racing with another mkdir */
+		mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
+	} else if (S_ISREG(mode)) {
+		inode->i_size = 0;
+		inode->i_fop = &cgroup_file_operations;
+	}
+	d_instantiate(dentry, inode);
+	dget(dentry);	/* Extra count - pin the dentry in core */
+	return 0;
+}
+
+/*
+ * cgroup_create_dir - create a directory for an object.
+ * @cgrp: the cgroup we create the directory for. It must have a valid
+ *        ->parent field. And we are going to fill its ->dentry field.
+ * @dentry: dentry of the new cgroup
+ * @mode: mode to set on new directory.
+ */
+static int cgroup_create_dir(struct cgroup *cgrp, struct dentry *dentry,
+				umode_t mode)
+{
+	struct dentry *parent;
+	int error = 0;
+
+	parent = cgrp->parent->dentry;
+	error = cgroup_create_file(dentry, S_IFDIR | mode, cgrp->root->sb);
+	if (!error) {
+		dentry->d_fsdata = cgrp;
+		inc_nlink(parent->d_inode);
+		rcu_assign_pointer(cgrp->dentry, dentry);
+		dget(dentry);
+	}
+	dput(dentry);
+
+	return error;
+}
+
+/**
+ * cgroup_file_mode - deduce file mode of a control file
+ * @cft: the control file in question
+ *
+ * returns cft->mode if ->mode is not 0
+ * returns S_IRUGO|S_IWUSR if it has both a read and a write handler
+ * returns S_IRUGO if it has only a read handler
+ * returns S_IWUSR if it has only a write hander
+ */
+static umode_t cgroup_file_mode(const struct cftype *cft)
+{
+	umode_t mode = 0;
+
+	if (cft->mode)
+		return cft->mode;
+
+	if (cft->read || cft->read_u64 || cft->read_s64 ||
+	    cft->read_map || cft->read_seq_string)
+		mode |= S_IRUGO;
+
+	if (cft->write || cft->write_u64 || cft->write_s64 ||
+	    cft->write_string || cft->trigger)
+		mode |= S_IWUSR;
+
+	return mode;
+}
+
+int cgroup_add_file(struct cgroup *cgrp,
+		       struct cgroup_subsys *subsys,
+		       const struct cftype *cft)
+{
+	struct dentry *dir = cgrp->dentry;
+	struct dentry *dentry;
+	int error;
+	umode_t mode;
+
+	char name[MAX_CGROUP_TYPE_NAMELEN + MAX_CFTYPE_NAME + 2] = { 0 };
+	if (subsys && !test_bit(ROOT_NOPREFIX, &cgrp->root->flags)) {
+		strcpy(name, subsys->name);
+		strcat(name, ".");
+	}
+	strcat(name, cft->name);
+	BUG_ON(!mutex_is_locked(&dir->d_inode->i_mutex));
+	dentry = lookup_one_len(name, dir, strlen(name));
+	if (!IS_ERR(dentry)) {
+		mode = cgroup_file_mode(cft);
+		error = cgroup_create_file(dentry, mode | S_IFREG,
+						cgrp->root->sb);
+		if (!error)
+			dentry->d_fsdata = (void *)cft;
+		dput(dentry);
+	} else
+		error = PTR_ERR(dentry);
+	return error;
+}
+EXPORT_SYMBOL_GPL(cgroup_add_file);
+
+int cgroup_add_files(struct cgroup *cgrp,
+			struct cgroup_subsys *subsys,
+			const struct cftype cft[],
+			int count)
+{
+	int i, err;
+	for (i = 0; i < count; i++) {
+		err = cgroup_add_file(cgrp, subsys, &cft[i]);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cgroup_add_files);
+
+/**
+ * cgroup_task_count - count the number of tasks in a cgroup.
+ * @cgrp: the cgroup in question
+ *
+ * Return the number of tasks in the cgroup.
+ */
+int cgroup_task_count(const struct cgroup *cgrp)
+{
+	int count = 0;
+	struct cg_cgroup_link *link;
+
+	read_lock(&css_set_lock);
+	list_for_each_entry(link, &cgrp->css_sets, cgrp_link_list) {
+		count += atomic_read(&link->cg->refcount);
+	}
+	read_unlock(&css_set_lock);
+	return count;
+}
+
+/*
+ * Advance a list_head iterator.  The iterator should be positioned at
+ * the start of a css_set
+ */
+static void cgroup_advance_iter(struct cgroup *cgrp,
+				struct cgroup_iter *it)
+{
+	struct list_head *l = it->cg_link;
+	struct cg_cgroup_link *link;
+	struct css_set *cg;
+
+	/* Advance to the next non-empty css_set */
+	do {
+		l = l->next;
+		if (l == &cgrp->css_sets) {
+			it->cg_link = NULL;
+			return;
+		}
+		link = list_entry(l, struct cg_cgroup_link, cgrp_link_list);
+		cg = link->cg;
+	} while (list_empty(&cg->tasks));
+	it->cg_link = l;
+	it->task = cg->tasks.next;
+}
+
+/*
+ * To reduce the fork() overhead for systems that are not actually
+ * using their cgroups capability, we don't maintain the lists running
+ * through each css_set to its tasks until we see the list actually
+ * used - in other words after the first call to cgroup_iter_start().
+ *
+ * The tasklist_lock is not held here, as do_each_thread() and
+ * while_each_thread() are protected by RCU.
+ */
+static void cgroup_enable_task_cg_lists(void)
+{
+	struct task_struct *p, *g;
+	write_lock(&css_set_lock);
+	use_task_css_set_links = 1;
+	do_each_thread(g, p) {
+		task_lock(p);
+		/*
+		 * We should check if the process is exiting, otherwise
+		 * it will race with cgroup_exit() in that the list
+		 * entry won't be deleted though the process has exited.
+		 */
+		if (!(p->flags & PF_EXITING) && list_empty(&p->cg_list))
+			list_add(&p->cg_list, &p->cgroups->tasks);
+		task_unlock(p);
+	} while_each_thread(g, p);
+	write_unlock(&css_set_lock);
+}
+
+void cgroup_iter_start(struct cgroup *cgrp, struct cgroup_iter *it)
+	__acquires(css_set_lock)
+{
+	/*
+	 * The first time anyone tries to iterate across a cgroup,
+	 * we need to enable the list linking each css_set to its
+	 * tasks, and fix up all existing tasks.
+	 */
+	if (!use_task_css_set_links)
+		cgroup_enable_task_cg_lists();
+
+	read_lock(&css_set_lock);
+	it->cg_link = &cgrp->css_sets;
+	cgroup_advance_iter(cgrp, it);
+}
+
+struct task_struct *cgroup_iter_next(struct cgroup *cgrp,
+					struct cgroup_iter *it)
+{
+	struct task_struct *res;
+	struct list_head *l = it->task;
+	struct cg_cgroup_link *link;
+
+	/* If the iterator cg is NULL, we have no tasks */
+	if (!it->cg_link)
+		return NULL;
+	res = list_entry(l, struct task_struct, cg_list);
+	/* Advance iterator to find next entry */
+	l = l->next;
+	link = list_entry(it->cg_link, struct cg_cgroup_link, cgrp_link_list);
+	if (l == &link->cg->tasks) {
+		/* We reached the end of this task list - move on to
+		 * the next cg_cgroup_link */
+		cgroup_advance_iter(cgrp, it);
+	} else {
+		it->task = l;
+	}
+	return res;
+}
+
+void cgroup_iter_end(struct cgroup *cgrp, struct cgroup_iter *it)
+	__releases(css_set_lock)
+{
+	read_unlock(&css_set_lock);
+}
+
+static inline int started_after_time(struct task_struct *t1,
+				     struct timespec *time,
+				     struct task_struct *t2)
+{
+	int start_diff = timespec_compare(&t1->start_time, time);
+	if (start_diff > 0) {
+		return 1;
+	} else if (start_diff < 0) {
+		return 0;
+	} else {
+		/*
+		 * Arbitrarily, if two processes started at the same
+		 * time, we'll say that the lower pointer value
+		 * started first. Note that t2 may have exited by now
+		 * so this may not be a valid pointer any longer, but
+		 * that's fine - it still serves to distinguish
+		 * between two tasks started (effectively) simultaneously.
+		 */
+		return t1 > t2;
+	}
+}
+
+/*
+ * This function is a callback from heap_insert() and is used to order
+ * the heap.
+ * In this case we order the heap in descending task start time.
+ */
+static inline int started_after(void *p1, void *p2)
+{
+	struct task_struct *t1 = p1;
+	struct task_struct *t2 = p2;
+	return started_after_time(t1, &t2->start_time, t2);
+}
+
+/**
+ * cgroup_scan_tasks - iterate though all the tasks in a cgroup
+ * @scan: struct cgroup_scanner containing arguments for the scan
+ *
+ * Arguments include pointers to callback functions test_task() and
+ * process_task().
+ * Iterate through all the tasks in a cgroup, calling test_task() for each,
+ * and if it returns true, call process_task() for it also.
+ * The test_task pointer may be NULL, meaning always true (select all tasks).
+ * Effectively duplicates cgroup_iter_{start,next,end}()
+ * but does not lock css_set_lock for the call to process_task().
+ * The struct cgroup_scanner may be embedded in any structure of the caller's
+ * creation.
+ * It is guaranteed that process_task() will act on every task that
+ * is a member of the cgroup for the duration of this call. This
+ * function may or may not call process_task() for tasks that exit
+ * or move to a different cgroup during the call, or are forked or
+ * move into the cgroup during the call.
+ *
+ * Note that test_task() may be called with locks held, and may in some
+ * situations be called multiple times for the same task, so it should
+ * be cheap.
+ * If the heap pointer in the struct cgroup_scanner is non-NULL, a heap has been
+ * pre-allocated and will be used for heap operations (and its "gt" member will
+ * be overwritten), else a temporary heap will be used (allocation of which
+ * may cause this function to fail).
+ */
+int cgroup_scan_tasks(struct cgroup_scanner *scan)
+{
+	int retval, i;
+	struct cgroup_iter it;
+	struct task_struct *p, *dropped;
+	/* Never dereference latest_task, since it's not refcounted */
+	struct task_struct *latest_task = NULL;
+	struct ptr_heap tmp_heap;
+	struct ptr_heap *heap;
+	struct timespec latest_time = { 0, 0 };
+
+	if (scan->heap) {
+		/* The caller supplied our heap and pre-allocated its memory */
+		heap = scan->heap;
+		heap->gt = &started_after;
+	} else {
+		/* We need to allocate our own heap memory */
+		heap = &tmp_heap;
+		retval = heap_init(heap, PAGE_SIZE, GFP_KERNEL, &started_after);
+		if (retval)
+			/* cannot allocate the heap */
+			return retval;
+	}
+
+ again:
+	/*
+	 * Scan tasks in the cgroup, using the scanner's "test_task" callback
+	 * to determine which are of interest, and using the scanner's
+	 * "process_task" callback to process any of them that need an update.
+	 * Since we don't want to hold any locks during the task updates,
+	 * gather tasks to be processed in a heap structure.
+	 * The heap is sorted by descending task start time.
+	 * If the statically-sized heap fills up, we overflow tasks that
+	 * started later, and in future iterations only consider tasks that
+	 * started after the latest task in the previous pass. This
+	 * guarantees forward progress and that we don't miss any tasks.
+	 */
+	heap->size = 0;
+	cgroup_iter_start(scan->cg, &it);
+	while ((p = cgroup_iter_next(scan->cg, &it))) {
+		/*
+		 * Only affect tasks that qualify per the caller's callback,
+		 * if he provided one
+		 */
+		if (scan->test_task && !scan->test_task(p, scan))
+			continue;
+		/*
+		 * Only process tasks that started after the last task
+		 * we processed
+		 */
+		if (!started_after_time(p, &latest_time, latest_task))
+			continue;
+		dropped = heap_insert(heap, p);
+		if (dropped == NULL) {
+			/*
+			 * The new task was inserted; the heap wasn't
+			 * previously full
+			 */
+			get_task_struct(p);
+		} else if (dropped != p) {
+			/*
+			 * The new task was inserted, and pushed out a
+			 * different task
+			 */
+			get_task_struct(p);
+			put_task_struct(dropped);
+		}
+		/*
+		 * Else the new task was newer than anything already in
+		 * the heap and wasn't inserted
+		 */
+	}
+	cgroup_iter_end(scan->cg, &it);
+
+	if (heap->size) {
+		for (i = 0; i < heap->size; i++) {
+			struct task_struct *q = heap->ptrs[i];
+			if (i == 0) {
+				latest_time = q->start_time;
+				latest_task = q;
+			}
+			/* Process the task per the caller's callback */
+			scan->process_task(q, scan);
+			put_task_struct(q);
+		}
+		/*
+		 * If we had to process any tasks at all, scan again
+		 * in case some of them were in the middle of forking
+		 * children that didn't get processed.
+		 * Not the most efficient way to do it, but it avoids
+		 * having to take callback_mutex in the fork path
+		 */
+		goto again;
+	}
+	if (heap == &tmp_heap)
+		heap_free(&tmp_heap);
+	return 0;
+}
+
+/*
+ * Stuff for reading the 'tasks'/'procs' files.
+ *
+ * Reading this file can return large amounts of data if a cgroup has
+ * *lots* of attached tasks. So it may need several calls to read(),
+ * but we cannot guarantee that the information we produce is correct
+ * unless we produce it entirely atomically.
+ *
+ */
+
+/*
+ * The following two functions "fix" the issue where there are more pids
+ * than kmalloc will give memory for; in such cases, we use vmalloc/vfree.
+ * TODO: replace with a kernel-wide solution to this problem
+ */
+#define PIDLIST_TOO_LARGE(c) ((c) * sizeof(pid_t) > (PAGE_SIZE * 2))
+static void *pidlist_allocate(int count)
+{
+	if (PIDLIST_TOO_LARGE(count))
+		return vmalloc(count * sizeof(pid_t));
+	else
+		return kmalloc(count * sizeof(pid_t), GFP_KERNEL);
+}
+static void pidlist_free(void *p)
+{
+	if (is_vmalloc_addr(p))
+		vfree(p);
+	else
+		kfree(p);
+}
+static void *pidlist_resize(void *p, int newcount)
+{
+	void *newlist;
+	/* note: if new alloc fails, old p will still be valid either way */
+	if (is_vmalloc_addr(p)) {
+		newlist = vmalloc(newcount * sizeof(pid_t));
+		if (!newlist)
+			return NULL;
+		memcpy(newlist, p, newcount * sizeof(pid_t));
+		vfree(p);
+	} else {
+		newlist = krealloc(p, newcount * sizeof(pid_t), GFP_KERNEL);
+	}
+	return newlist;
+}
+
+/*
+ * pidlist_uniq - given a kmalloc()ed list, strip out all duplicate entries
+ * If the new stripped list is sufficiently smaller and there's enough memory
+ * to allocate a new buffer, will let go of the unneeded memory. Returns the
+ * number of unique elements.
+ */
+/* is the size difference enough that we should re-allocate the array? */
+#define PIDLIST_REALLOC_DIFFERENCE(old, new) ((old) - PAGE_SIZE >= (new))
+static int pidlist_uniq(pid_t **p, int length)
+{
+	int src, dest = 1;
+	pid_t *list = *p;
+	pid_t *newlist;
+
+	/*
+	 * we presume the 0th element is unique, so i starts at 1. trivial
+	 * edge cases first; no work needs to be done for either
+	 */
+	if (length == 0 || length == 1)
+		return length;
+	/* src and dest walk down the list; dest counts unique elements */
+	for (src = 1; src < length; src++) {
+		/* find next unique element */
+		while (list[src] == list[src-1]) {
+			src++;
+			if (src == length)
+				goto after;
+		}
+		/* dest always points to where the next unique element goes */
+		list[dest] = list[src];
+		dest++;
+	}
+after:
+	/*
+	 * if the length difference is large enough, we want to allocate a
+	 * smaller buffer to save memory. if this fails due to out of memory,
+	 * we'll just stay with what we've got.
+	 */
+	if (PIDLIST_REALLOC_DIFFERENCE(length, dest)) {
+		newlist = pidlist_resize(list, dest);
+		if (newlist)
+			*p = newlist;
+	}
+	return dest;
+}
+
+static int cmppid(const void *a, const void *b)
+{
+	return *(pid_t *)a - *(pid_t *)b;
+}
+
+/*
+ * find the appropriate pidlist for our purpose (given procs vs tasks)
+ * returns with the lock on that pidlist already held, and takes care
+ * of the use count, or returns NULL with no locks held if we're out of
+ * memory.
+ */
+static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp,
+						  enum cgroup_filetype type)
+{
+	struct cgroup_pidlist *l;
+	/* don't need task_nsproxy() if we're looking at ourself */
+	struct pid_namespace *ns = current->nsproxy->pid_ns;
+
+	/*
+	 * We can't drop the pidlist_mutex before taking the l->mutex in case
+	 * the last ref-holder is trying to remove l from the list at the same
+	 * time. Holding the pidlist_mutex precludes somebody taking whichever
+	 * list we find out from under us - compare release_pid_array().
+	 */
+	mutex_lock(&cgrp->pidlist_mutex);
+	list_for_each_entry(l, &cgrp->pidlists, links) {
+		if (l->key.type == type && l->key.ns == ns) {
+			/* make sure l doesn't vanish out from under us */
+			down_write(&l->mutex);
+			mutex_unlock(&cgrp->pidlist_mutex);
+			return l;
+		}
+	}
+	/* entry not found; create a new one */
+	l = kmalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL);
+	if (!l) {
+		mutex_unlock(&cgrp->pidlist_mutex);
+		return l;
+	}
+	init_rwsem(&l->mutex);
+	down_write(&l->mutex);
+	l->key.type = type;
+	l->key.ns = get_pid_ns(ns);
+	l->use_count = 0; /* don't increment here */
+	l->list = NULL;
+	l->owner = cgrp;
+	list_add(&l->links, &cgrp->pidlists);
+	mutex_unlock(&cgrp->pidlist_mutex);
+	return l;
+}
+
+/*
+ * Load a cgroup's pidarray with either procs' tgids or tasks' pids
+ */
+static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type,
+			      struct cgroup_pidlist **lp)
+{
+	pid_t *array;
+	int length;
+	int pid, n = 0; /* used for populating the array */
+	struct cgroup_iter it;
+	struct task_struct *tsk;
+	struct cgroup_pidlist *l;
+
+	/*
+	 * If cgroup gets more users after we read count, we won't have
+	 * enough space - tough.  This race is indistinguishable to the
+	 * caller from the case that the additional cgroup users didn't
+	 * show up until sometime later on.
+	 */
+	length = cgroup_task_count(cgrp);
+	array = pidlist_allocate(length);
+	if (!array)
+		return -ENOMEM;
+	/* now, populate the array */
+	cgroup_iter_start(cgrp, &it);
+	while ((tsk = cgroup_iter_next(cgrp, &it))) {
+		if (unlikely(n == length))
+			break;
+		/* get tgid or pid for procs or tasks file respectively */
+		if (type == CGROUP_FILE_PROCS)
+			pid = task_tgid_vnr(tsk);
+		else
+			pid = task_pid_vnr(tsk);
+		if (pid > 0) /* make sure to only use valid results */
+			array[n++] = pid;
+	}
+	cgroup_iter_end(cgrp, &it);
+	length = n;
+	/* now sort & (if procs) strip out duplicates */
+	sort(array, length, sizeof(pid_t), cmppid, NULL);
+	if (type == CGROUP_FILE_PROCS)
+		length = pidlist_uniq(&array, length);
+	l = cgroup_pidlist_find(cgrp, type);
+	if (!l) {
+		pidlist_free(array);
+		return -ENOMEM;
+	}
+	/* store array, freeing old if necessary - lock already held */
+	pidlist_free(l->list);
+	l->list = array;
+	l->length = length;
+	l->use_count++;
+	up_write(&l->mutex);
+	*lp = l;
+	return 0;
+}
+
+/**
+ * cgroupstats_build - build and fill cgroupstats
+ * @stats: cgroupstats to fill information into
+ * @dentry: A dentry entry belonging to the cgroup for which stats have
+ * been requested.
+ *
+ * Build and fill cgroupstats so that taskstats can export it to user
+ * space.
+ */
+int cgroupstats_build(struct cgroupstats *stats, struct dentry *dentry)
+{
+	int ret = -EINVAL;
+	struct cgroup *cgrp;
+	struct cgroup_iter it;
+	struct task_struct *tsk;
+
+	/*
+	 * Validate dentry by checking the superblock operations,
+	 * and make sure it's a directory.
+	 */
+	if (dentry->d_sb->s_op != &cgroup_ops ||
+	    !S_ISDIR(dentry->d_inode->i_mode))
+		 goto err;
+
+	ret = 0;
+	cgrp = dentry->d_fsdata;
+
+	cgroup_iter_start(cgrp, &it);
+	while ((tsk = cgroup_iter_next(cgrp, &it))) {
+		switch (tsk->state) {
+		case TASK_RUNNING:
+			stats->nr_running++;
+			break;
+		case TASK_INTERRUPTIBLE:
+			stats->nr_sleeping++;
+			break;
+		case TASK_UNINTERRUPTIBLE:
+			stats->nr_uninterruptible++;
+			break;
+		case TASK_STOPPED:
+			stats->nr_stopped++;
+			break;
+		default:
+			if (delayacct_is_task_waiting_on_io(tsk))
+				stats->nr_io_wait++;
+			break;
+		}
+	}
+	cgroup_iter_end(cgrp, &it);
+
+err:
+	return ret;
+}
+
+
+/*
+ * seq_file methods for the tasks/procs files. The seq_file position is the
+ * next pid to display; the seq_file iterator is a pointer to the pid
+ * in the cgroup->l->list array.
+ */
+
+static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos)
+{
+	/*
+	 * Initially we receive a position value that corresponds to
+	 * one more than the last pid shown (or 0 on the first call or
+	 * after a seek to the start). Use a binary-search to find the
+	 * next pid to display, if any
+	 */
+	struct cgroup_pidlist *l = s->private;
+	int index = 0, pid = *pos;
+	int *iter;
+
+	down_read(&l->mutex);
+	if (pid) {
+		int end = l->length;
+
+		while (index < end) {
+			int mid = (index + end) / 2;
+			if (l->list[mid] == pid) {
+				index = mid;
+				break;
+			} else if (l->list[mid] <= pid)
+				index = mid + 1;
+			else
+				end = mid;
+		}
+	}
+	/* If we're off the end of the array, we're done */
+	if (index >= l->length)
+		return NULL;
+	/* Update the abstract position to be the actual pid that we found */
+	iter = l->list + index;
+	*pos = *iter;
+	return iter;
+}
+
+static void cgroup_pidlist_stop(struct seq_file *s, void *v)
+{
+	struct cgroup_pidlist *l = s->private;
+	up_read(&l->mutex);
+}
+
+static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos)
+{
+	struct cgroup_pidlist *l = s->private;
+	pid_t *p = v;
+	pid_t *end = l->list + l->length;
+	/*
+	 * Advance to the next pid in the array. If this goes off the
+	 * end, we're done
+	 */
+	p++;
+	if (p >= end) {
+		return NULL;
+	} else {
+		*pos = *p;
+		return p;
+	}
+}
+
+static int cgroup_pidlist_show(struct seq_file *s, void *v)
+{
+	return seq_printf(s, "%d\n", *(int *)v);
+}
+
+/*
+ * seq_operations functions for iterating on pidlists through seq_file -
+ * independent of whether it's tasks or procs
+ */
+static const struct seq_operations cgroup_pidlist_seq_operations = {
+	.start = cgroup_pidlist_start,
+	.stop = cgroup_pidlist_stop,
+	.next = cgroup_pidlist_next,
+	.show = cgroup_pidlist_show,
+};
+
+static void cgroup_release_pid_array(struct cgroup_pidlist *l)
+{
+	/*
+	 * the case where we're the last user of this particular pidlist will
+	 * have us remove it from the cgroup's list, which entails taking the
+	 * mutex. since in pidlist_find the pidlist->lock depends on cgroup->
+	 * pidlist_mutex, we have to take pidlist_mutex first.
+	 */
+	mutex_lock(&l->owner->pidlist_mutex);
+	down_write(&l->mutex);
+	BUG_ON(!l->use_count);
+	if (!--l->use_count) {
+		/* we're the last user if refcount is 0; remove and free */
+		list_del(&l->links);
+		mutex_unlock(&l->owner->pidlist_mutex);
+		pidlist_free(l->list);
+		put_pid_ns(l->key.ns);
+		up_write(&l->mutex);
+		kfree(l);
+		return;
+	}
+	mutex_unlock(&l->owner->pidlist_mutex);
+	up_write(&l->mutex);
+}
+
+static int cgroup_pidlist_release(struct inode *inode, struct file *file)
+{
+	struct cgroup_pidlist *l;
+	if (!(file->f_mode & FMODE_READ))
+		return 0;
+	/*
+	 * the seq_file will only be initialized if the file was opened for
+	 * reading; hence we check if it's not null only in that case.
+	 */
+	l = ((struct seq_file *)file->private_data)->private;
+	cgroup_release_pid_array(l);
+	return seq_release(inode, file);
+}
+
+static const struct file_operations cgroup_pidlist_operations = {
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.write = cgroup_file_write,
+	.release = cgroup_pidlist_release,
+};
+
+/*
+ * The following functions handle opens on a file that displays a pidlist
+ * (tasks or procs). Prepare an array of the process/thread IDs of whoever's
+ * in the cgroup.
+ */
+/* helper function for the two below it */
+static int cgroup_pidlist_open(struct file *file, enum cgroup_filetype type)
+{
+	struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent);
+	struct cgroup_pidlist *l;
+	int retval;
+
+	/* Nothing to do for write-only files */
+	if (!(file->f_mode & FMODE_READ))
+		return 0;
+
+	/* have the array populated */
+	retval = pidlist_array_load(cgrp, type, &l);
+	if (retval)
+		return retval;
+	/* configure file information */
+	file->f_op = &cgroup_pidlist_operations;
+
+	retval = seq_open(file, &cgroup_pidlist_seq_operations);
+	if (retval) {
+		cgroup_release_pid_array(l);
+		return retval;
+	}
+	((struct seq_file *)file->private_data)->private = l;
+	return 0;
+}
+static int cgroup_tasks_open(struct inode *unused, struct file *file)
+{
+	return cgroup_pidlist_open(file, CGROUP_FILE_TASKS);
+}
+static int cgroup_procs_open(struct inode *unused, struct file *file)
+{
+	return cgroup_pidlist_open(file, CGROUP_FILE_PROCS);
+}
+
+static u64 cgroup_read_notify_on_release(struct cgroup *cgrp,
+					    struct cftype *cft)
+{
+	return notify_on_release(cgrp);
+}
+
+static int cgroup_write_notify_on_release(struct cgroup *cgrp,
+					  struct cftype *cft,
+					  u64 val)
+{
+	clear_bit(CGRP_RELEASABLE, &cgrp->flags);
+	if (val)
+		set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
+	else
+		clear_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
+	return 0;
+}
+
+/*
+ * Unregister event and free resources.
+ *
+ * Gets called from workqueue.
+ */
+static void cgroup_event_remove(struct work_struct *work)
+{
+	struct cgroup_event *event = container_of(work, struct cgroup_event,
+			remove);
+	struct cgroup *cgrp = event->cgrp;
+
+	event->cft->unregister_event(cgrp, event->cft, event->eventfd);
+
+	eventfd_ctx_put(event->eventfd);
+	kfree(event);
+	dput(cgrp->dentry);
+}
+
+/*
+ * Gets called on POLLHUP on eventfd when user closes it.
+ *
+ * Called with wqh->lock held and interrupts disabled.
+ */
+static int cgroup_event_wake(wait_queue_t *wait, unsigned mode,
+		int sync, void *key)
+{
+	struct cgroup_event *event = container_of(wait,
+			struct cgroup_event, wait);
+	struct cgroup *cgrp = event->cgrp;
+	unsigned long flags = (unsigned long)key;
+
+	if (flags & POLLHUP) {
+		__remove_wait_queue(event->wqh, &event->wait);
+		spin_lock(&cgrp->event_list_lock);
+		list_del(&event->list);
+		spin_unlock(&cgrp->event_list_lock);
+		/*
+		 * We are in atomic context, but cgroup_event_remove() may
+		 * sleep, so we have to call it in workqueue.
+		 */
+		schedule_work(&event->remove);
+	}
+
+	return 0;
+}
+
+static void cgroup_event_ptable_queue_proc(struct file *file,
+		wait_queue_head_t *wqh, poll_table *pt)
+{
+	struct cgroup_event *event = container_of(pt,
+			struct cgroup_event, pt);
+
+	event->wqh = wqh;
+	add_wait_queue(wqh, &event->wait);
+}
+
+/*
+ * Parse input and register new cgroup event handler.
+ *
+ * Input must be in format '<event_fd> <control_fd> <args>'.
+ * Interpretation of args is defined by control file implementation.
+ */
+static int cgroup_write_event_control(struct cgroup *cgrp, struct cftype *cft,
+				      const char *buffer)
+{
+	struct cgroup_event *event = NULL;
+	unsigned int efd, cfd;
+	struct file *efile = NULL;
+	struct file *cfile = NULL;
+	char *endp;
+	int ret;
+
+	efd = simple_strtoul(buffer, &endp, 10);
+	if (*endp != ' ')
+		return -EINVAL;
+	buffer = endp + 1;
+
+	cfd = simple_strtoul(buffer, &endp, 10);
+	if ((*endp != ' ') && (*endp != '\0'))
+		return -EINVAL;
+	buffer = endp + 1;
+
+	event = kzalloc(sizeof(*event), GFP_KERNEL);
+	if (!event)
+		return -ENOMEM;
+	event->cgrp = cgrp;
+	INIT_LIST_HEAD(&event->list);
+	init_poll_funcptr(&event->pt, cgroup_event_ptable_queue_proc);
+	init_waitqueue_func_entry(&event->wait, cgroup_event_wake);
+	INIT_WORK(&event->remove, cgroup_event_remove);
+
+	efile = eventfd_fget(efd);
+	if (IS_ERR(efile)) {
+		ret = PTR_ERR(efile);
+		goto fail;
+	}
+
+	event->eventfd = eventfd_ctx_fileget(efile);
+	if (IS_ERR(event->eventfd)) {
+		ret = PTR_ERR(event->eventfd);
+		goto fail;
+	}
+
+	cfile = fget(cfd);
+	if (!cfile) {
+		ret = -EBADF;
+		goto fail;
+	}
+
+	/* the process need read permission on control file */
+	/* AV: shouldn't we check that it's been opened for read instead? */
+	ret = inode_permission(cfile->f_path.dentry->d_inode, MAY_READ);
+	if (ret < 0)
+		goto fail;
+
+	event->cft = __file_cft(cfile);
+	if (IS_ERR(event->cft)) {
+		ret = PTR_ERR(event->cft);
+		goto fail;
+	}
+
+	if (!event->cft->register_event || !event->cft->unregister_event) {
+		ret = -EINVAL;
+		goto fail;
+	}
+
+	ret = event->cft->register_event(cgrp, event->cft,
+			event->eventfd, buffer);
+	if (ret)
+		goto fail;
+
+	if (efile->f_op->poll(efile, &event->pt) & POLLHUP) {
+		event->cft->unregister_event(cgrp, event->cft, event->eventfd);
+		ret = 0;
+		goto fail;
+	}
+
+	/*
+	 * Events should be removed after rmdir of cgroup directory, but before
+	 * destroying subsystem state objects. Let's take reference to cgroup
+	 * directory dentry to do that.
+	 */
+	dget(cgrp->dentry);
+
+	spin_lock(&cgrp->event_list_lock);
+	list_add(&event->list, &cgrp->event_list);
+	spin_unlock(&cgrp->event_list_lock);
+
+	fput(cfile);
+	fput(efile);
+
+	return 0;
+
+fail:
+	if (cfile)
+		fput(cfile);
+
+	if (event && event->eventfd && !IS_ERR(event->eventfd))
+		eventfd_ctx_put(event->eventfd);
+
+	if (!IS_ERR_OR_NULL(efile))
+		fput(efile);
+
+	kfree(event);
+
+	return ret;
+}
+
+static u64 cgroup_clone_children_read(struct cgroup *cgrp,
+				    struct cftype *cft)
+{
+	return clone_children(cgrp);
+}
+
+static int cgroup_clone_children_write(struct cgroup *cgrp,
+				     struct cftype *cft,
+				     u64 val)
+{
+	if (val)
+		set_bit(CGRP_CLONE_CHILDREN, &cgrp->flags);
+	else
+		clear_bit(CGRP_CLONE_CHILDREN, &cgrp->flags);
+	return 0;
+}
+
+/*
+ * for the common functions, 'private' gives the type of file
+ */
+/* for hysterical raisins, we can't put this on the older files */
+#define CGROUP_FILE_GENERIC_PREFIX "cgroup."
+static struct cftype files[] = {
+	{
+		.name = "tasks",
+		.open = cgroup_tasks_open,
+		.write_u64 = cgroup_tasks_write,
+		.release = cgroup_pidlist_release,
+		.mode = S_IRUGO | S_IWUSR,
+	},
+	{
+		.name = CGROUP_FILE_GENERIC_PREFIX "procs",
+		.open = cgroup_procs_open,
+		.write_u64 = cgroup_procs_write,
+		.release = cgroup_pidlist_release,
+		.mode = S_IRUGO | S_IWUSR,
+	},
+	{
+		.name = "notify_on_release",
+		.read_u64 = cgroup_read_notify_on_release,
+		.write_u64 = cgroup_write_notify_on_release,
+	},
+	{
+		.name = CGROUP_FILE_GENERIC_PREFIX "event_control",
+		.write_string = cgroup_write_event_control,
+		.mode = S_IWUGO,
+	},
+	{
+		.name = "cgroup.clone_children",
+		.read_u64 = cgroup_clone_children_read,
+		.write_u64 = cgroup_clone_children_write,
+	},
+};
+
+static struct cftype cft_release_agent = {
+	.name = "release_agent",
+	.read_seq_string = cgroup_release_agent_show,
+	.write_string = cgroup_release_agent_write,
+	.max_write_len = PATH_MAX,
+};
+
+static int cgroup_populate_dir(struct cgroup *cgrp)
+{
+	int err;
+	struct cgroup_subsys *ss;
+
+	/* First clear out any existing files */
+	cgroup_clear_directory(cgrp->dentry);
+
+	err = cgroup_add_files(cgrp, NULL, files, ARRAY_SIZE(files));
+	if (err < 0)
+		return err;
+
+	if (cgrp == cgrp->top_cgroup) {
+		if ((err = cgroup_add_file(cgrp, NULL, &cft_release_agent)) < 0)
+			return err;
+	}
+
+	for_each_subsys(cgrp->root, ss) {
+		if (ss->populate && (err = ss->populate(ss, cgrp)) < 0)
+			return err;
+	}
+	/* This cgroup is ready now */
+	for_each_subsys(cgrp->root, ss) {
+		struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
+		/*
+		 * Update id->css pointer and make this css visible from
+		 * CSS ID functions. This pointer will be dereferened
+		 * from RCU-read-side without locks.
+		 */
+		if (css->id)
+			rcu_assign_pointer(css->id->css, css);
+	}
+
+	return 0;
+}
+
+static void init_cgroup_css(struct cgroup_subsys_state *css,
+			       struct cgroup_subsys *ss,
+			       struct cgroup *cgrp)
+{
+	css->cgroup = cgrp;
+	atomic_set(&css->refcnt, 1);
+	css->flags = 0;
+	css->id = NULL;
+	if (cgrp == dummytop)
+		set_bit(CSS_ROOT, &css->flags);
+	BUG_ON(cgrp->subsys[ss->subsys_id]);
+	cgrp->subsys[ss->subsys_id] = css;
+}
+
+static void cgroup_lock_hierarchy(struct cgroupfs_root *root)
+{
+	/* We need to take each hierarchy_mutex in a consistent order */
+	int i;
+
+	/*
+	 * No worry about a race with rebind_subsystems that might mess up the
+	 * locking order, since both parties are under cgroup_mutex.
+	 */
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+		struct cgroup_subsys *ss = subsys[i];
+		if (ss == NULL)
+			continue;
+		if (ss->root == root)
+			mutex_lock(&ss->hierarchy_mutex);
+	}
+}
+
+static void cgroup_unlock_hierarchy(struct cgroupfs_root *root)
+{
+	int i;
+
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+		struct cgroup_subsys *ss = subsys[i];
+		if (ss == NULL)
+			continue;
+		if (ss->root == root)
+			mutex_unlock(&ss->hierarchy_mutex);
+	}
+}
+
+/*
+ * cgroup_create - create a cgroup
+ * @parent: cgroup that will be parent of the new cgroup
+ * @dentry: dentry of the new cgroup
+ * @mode: mode to set on new inode
+ *
+ * Must be called with the mutex on the parent inode held
+ */
+static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
+			     umode_t mode)
+{
+	struct cgroup *cgrp;
+	struct cgroupfs_root *root = parent->root;
+	int err = 0;
+	struct cgroup_subsys *ss;
+	struct super_block *sb = root->sb;
+
+	cgrp = kzalloc(sizeof(*cgrp), GFP_KERNEL);
+	if (!cgrp)
+		return -ENOMEM;
+
+	/* Grab a reference on the superblock so the hierarchy doesn't
+	 * get deleted on unmount if there are child cgroups.  This
+	 * can be done outside cgroup_mutex, since the sb can't
+	 * disappear while someone has an open control file on the
+	 * fs */
+	atomic_inc(&sb->s_active);
+
+	mutex_lock(&cgroup_mutex);
+
+	init_cgroup_housekeeping(cgrp);
+
+	cgrp->parent = parent;
+	cgrp->root = parent->root;
+	cgrp->top_cgroup = parent->top_cgroup;
+
+	if (notify_on_release(parent))
+		set_bit(CGRP_NOTIFY_ON_RELEASE, &cgrp->flags);
+
+	if (clone_children(parent))
+		set_bit(CGRP_CLONE_CHILDREN, &cgrp->flags);
+
+	for_each_subsys(root, ss) {
+		struct cgroup_subsys_state *css = ss->create(ss, cgrp);
+
+		if (IS_ERR(css)) {
+			err = PTR_ERR(css);
+			goto err_destroy;
+		}
+		init_cgroup_css(css, ss, cgrp);
+		if (ss->use_id) {
+			err = alloc_css_id(ss, parent, cgrp);
+			if (err)
+				goto err_destroy;
+		}
+		/* At error, ->destroy() callback has to free assigned ID. */
+		if (clone_children(parent) && ss->post_clone)
+			ss->post_clone(ss, cgrp);
+	}
+
+	cgroup_lock_hierarchy(root);
+	list_add(&cgrp->sibling, &cgrp->parent->children);
+	cgroup_unlock_hierarchy(root);
+	root->number_of_cgroups++;
+
+	err = cgroup_create_dir(cgrp, dentry, mode);
+	if (err < 0)
+		goto err_remove;
+
+	/* The cgroup directory was pre-locked for us */
+	BUG_ON(!mutex_is_locked(&cgrp->dentry->d_inode->i_mutex));
+
+	err = cgroup_populate_dir(cgrp);
+	/* If err < 0, we have a half-filled directory - oh well ;) */
+
+	mutex_unlock(&cgroup_mutex);
+	mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
+
+	return 0;
+
+ err_remove:
+
+	cgroup_lock_hierarchy(root);
+	list_del(&cgrp->sibling);
+	cgroup_unlock_hierarchy(root);
+	root->number_of_cgroups--;
+
+ err_destroy:
+
+	for_each_subsys(root, ss) {
+		if (cgrp->subsys[ss->subsys_id])
+			ss->destroy(ss, cgrp);
+	}
+
+	mutex_unlock(&cgroup_mutex);
+
+	/* Release the reference count that we took on the superblock */
+	deactivate_super(sb);
+
+	kfree(cgrp);
+	return err;
+}
+
+static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+	struct cgroup *c_parent = dentry->d_parent->d_fsdata;
+
+	/* the vfs holds inode->i_mutex already */
+	return cgroup_create(c_parent, dentry, mode | S_IFDIR);
+}
+
+static int cgroup_has_css_refs(struct cgroup *cgrp)
+{
+	/* Check the reference count on each subsystem. Since we
+	 * already established that there are no tasks in the
+	 * cgroup, if the css refcount is also 1, then there should
+	 * be no outstanding references, so the subsystem is safe to
+	 * destroy. We scan across all subsystems rather than using
+	 * the per-hierarchy linked list of mounted subsystems since
+	 * we can be called via check_for_release() with no
+	 * synchronization other than RCU, and the subsystem linked
+	 * list isn't RCU-safe */
+	int i;
+	/*
+	 * We won't need to lock the subsys array, because the subsystems
+	 * we're concerned about aren't going anywhere since our cgroup root
+	 * has a reference on them.
+	 */
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+		struct cgroup_subsys *ss = subsys[i];
+		struct cgroup_subsys_state *css;
+		/* Skip subsystems not present or not in this hierarchy */
+		if (ss == NULL || ss->root != cgrp->root)
+			continue;
+		css = cgrp->subsys[ss->subsys_id];
+		/* When called from check_for_release() it's possible
+		 * that by this point the cgroup has been removed
+		 * and the css deleted. But a false-positive doesn't
+		 * matter, since it can only happen if the cgroup
+		 * has been deleted and hence no longer needs the
+		 * release agent to be called anyway. */
+		if (css && (atomic_read(&css->refcnt) > 1))
+			return 1;
+	}
+	return 0;
+}
+
+/*
+ * Atomically mark all (or else none) of the cgroup's CSS objects as
+ * CSS_REMOVED. Return true on success, or false if the cgroup has
+ * busy subsystems. Call with cgroup_mutex held
+ */
+
+static int cgroup_clear_css_refs(struct cgroup *cgrp)
+{
+	struct cgroup_subsys *ss;
+	unsigned long flags;
+	bool failed = false;
+	local_irq_save(flags);
+	for_each_subsys(cgrp->root, ss) {
+		struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
+		int refcnt;
+		while (1) {
+			/* We can only remove a CSS with a refcnt==1 */
+			refcnt = atomic_read(&css->refcnt);
+			if (refcnt > 1) {
+				failed = true;
+				goto done;
+			}
+			BUG_ON(!refcnt);
+			/*
+			 * Drop the refcnt to 0 while we check other
+			 * subsystems. This will cause any racing
+			 * css_tryget() to spin until we set the
+			 * CSS_REMOVED bits or abort
+			 */
+			if (atomic_cmpxchg(&css->refcnt, refcnt, 0) == refcnt)
+				break;
+			cpu_relax();
+		}
+	}
+ done:
+	for_each_subsys(cgrp->root, ss) {
+		struct cgroup_subsys_state *css = cgrp->subsys[ss->subsys_id];
+		if (failed) {
+			/*
+			 * Restore old refcnt if we previously managed
+			 * to clear it from 1 to 0
+			 */
+			if (!atomic_read(&css->refcnt))
+				atomic_set(&css->refcnt, 1);
+		} else {
+			/* Commit the fact that the CSS is removed */
+			set_bit(CSS_REMOVED, &css->flags);
+		}
+	}
+	local_irq_restore(flags);
+	return !failed;
+}
+
+static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry)
+{
+	struct cgroup *cgrp = dentry->d_fsdata;
+	struct dentry *d;
+	struct cgroup *parent;
+	DEFINE_WAIT(wait);
+	struct cgroup_event *event, *tmp;
+	int ret;
+
+	/* the vfs holds both inode->i_mutex already */
+again:
+	mutex_lock(&cgroup_mutex);
+	if (atomic_read(&cgrp->count) != 0) {
+		mutex_unlock(&cgroup_mutex);
+		return -EBUSY;
+	}
+	if (!list_empty(&cgrp->children)) {
+		mutex_unlock(&cgroup_mutex);
+		return -EBUSY;
+	}
+	mutex_unlock(&cgroup_mutex);
+
+	/*
+	 * In general, subsystem has no css->refcnt after pre_destroy(). But
+	 * in racy cases, subsystem may have to get css->refcnt after
+	 * pre_destroy() and it makes rmdir return with -EBUSY. This sometimes
+	 * make rmdir return -EBUSY too often. To avoid that, we use waitqueue
+	 * for cgroup's rmdir. CGRP_WAIT_ON_RMDIR is for synchronizing rmdir
+	 * and subsystem's reference count handling. Please see css_get/put
+	 * and css_tryget() and cgroup_wakeup_rmdir_waiter() implementation.
+	 */
+	set_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags);
+
+	/*
+	 * Call pre_destroy handlers of subsys. Notify subsystems
+	 * that rmdir() request comes.
+	 */
+	ret = cgroup_call_pre_destroy(cgrp);
+	if (ret) {
+		clear_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags);
+		return ret;
+	}
+
+	mutex_lock(&cgroup_mutex);
+	parent = cgrp->parent;
+	if (atomic_read(&cgrp->count) || !list_empty(&cgrp->children)) {
+		clear_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags);
+		mutex_unlock(&cgroup_mutex);
+		return -EBUSY;
+	}
+	prepare_to_wait(&cgroup_rmdir_waitq, &wait, TASK_INTERRUPTIBLE);
+	if (!cgroup_clear_css_refs(cgrp)) {
+		mutex_unlock(&cgroup_mutex);
+		/*
+		 * Because someone may call cgroup_wakeup_rmdir_waiter() before
+		 * prepare_to_wait(), we need to check this flag.
+		 */
+		if (test_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags))
+			schedule();
+		finish_wait(&cgroup_rmdir_waitq, &wait);
+		clear_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags);
+		if (signal_pending(current))
+			return -EINTR;
+		goto again;
+	}
+	/* NO css_tryget() can success after here. */
+	finish_wait(&cgroup_rmdir_waitq, &wait);
+	clear_bit(CGRP_WAIT_ON_RMDIR, &cgrp->flags);
+
+	raw_spin_lock(&release_list_lock);
+	set_bit(CGRP_REMOVED, &cgrp->flags);
+	if (!list_empty(&cgrp->release_list))
+		list_del_init(&cgrp->release_list);
+	raw_spin_unlock(&release_list_lock);
+
+	cgroup_lock_hierarchy(cgrp->root);
+	/* delete this cgroup from parent->children */
+	list_del_init(&cgrp->sibling);
+	cgroup_unlock_hierarchy(cgrp->root);
+
+	d = dget(cgrp->dentry);
+
+	cgroup_d_remove_dir(d);
+	dput(d);
+
+	set_bit(CGRP_RELEASABLE, &parent->flags);
+	check_for_release(parent);
+
+	/*
+	 * Unregister events and notify userspace.
+	 * Notify userspace about cgroup removing only after rmdir of cgroup
+	 * directory to avoid race between userspace and kernelspace
+	 */
+	spin_lock(&cgrp->event_list_lock);
+	list_for_each_entry_safe(event, tmp, &cgrp->event_list, list) {
+		list_del(&event->list);
+		remove_wait_queue(event->wqh, &event->wait);
+		eventfd_signal(event->eventfd, 1);
+		schedule_work(&event->remove);
+	}
+	spin_unlock(&cgrp->event_list_lock);
+
+	mutex_unlock(&cgroup_mutex);
+	return 0;
+}
+
+static void __init cgroup_init_subsys(struct cgroup_subsys *ss)
+{
+	struct cgroup_subsys_state *css;
+
+	printk(KERN_INFO "Initializing cgroup subsys %s\n", ss->name);
+
+	/* Create the top cgroup state for this subsystem */
+	list_add(&ss->sibling, &rootnode.subsys_list);
+	ss->root = &rootnode;
+	css = ss->create(ss, dummytop);
+	/* We don't handle early failures gracefully */
+	BUG_ON(IS_ERR(css));
+	init_cgroup_css(css, ss, dummytop);
+
+	/* Update the init_css_set to contain a subsys
+	 * pointer to this state - since the subsystem is
+	 * newly registered, all tasks and hence the
+	 * init_css_set is in the subsystem's top cgroup. */
+	init_css_set.subsys[ss->subsys_id] = dummytop->subsys[ss->subsys_id];
+
+	need_forkexit_callback |= ss->fork || ss->exit;
+
+	/* At system boot, before all subsystems have been
+	 * registered, no tasks have been forked, so we don't
+	 * need to invoke fork callbacks here. */
+	BUG_ON(!list_empty(&init_task.tasks));
+
+	mutex_init(&ss->hierarchy_mutex);
+	lockdep_set_class(&ss->hierarchy_mutex, &ss->subsys_key);
+	ss->active = 1;
+
+	/* this function shouldn't be used with modular subsystems, since they
+	 * need to register a subsys_id, among other things */
+	BUG_ON(ss->module);
+}
+
+/**
+ * cgroup_load_subsys: load and register a modular subsystem at runtime
+ * @ss: the subsystem to load
+ *
+ * This function should be called in a modular subsystem's initcall. If the
+ * subsystem is built as a module, it will be assigned a new subsys_id and set
+ * up for use. If the subsystem is built-in anyway, work is delegated to the
+ * simpler cgroup_init_subsys.
+ */
+int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss)
+{
+	int i;
+	struct cgroup_subsys_state *css;
+
+	/* check name and function validity */
+	if (ss->name == NULL || strlen(ss->name) > MAX_CGROUP_TYPE_NAMELEN ||
+	    ss->create == NULL || ss->destroy == NULL)
+		return -EINVAL;
+
+	/*
+	 * we don't support callbacks in modular subsystems. this check is
+	 * before the ss->module check for consistency; a subsystem that could
+	 * be a module should still have no callbacks even if the user isn't
+	 * compiling it as one.
+	 */
+	if (ss->fork || ss->exit)
+		return -EINVAL;
+
+	/*
+	 * an optionally modular subsystem is built-in: we want to do nothing,
+	 * since cgroup_init_subsys will have already taken care of it.
+	 */
+	if (ss->module == NULL) {
+		/* a few sanity checks */
+		BUG_ON(ss->subsys_id >= CGROUP_BUILTIN_SUBSYS_COUNT);
+		BUG_ON(subsys[ss->subsys_id] != ss);
+		return 0;
+	}
+
+	/*
+	 * need to register a subsys id before anything else - for example,
+	 * init_cgroup_css needs it.
+	 */
+	mutex_lock(&cgroup_mutex);
+	/* find the first empty slot in the array */
+	for (i = CGROUP_BUILTIN_SUBSYS_COUNT; i < CGROUP_SUBSYS_COUNT; i++) {
+		if (subsys[i] == NULL)
+			break;
+	}
+	if (i == CGROUP_SUBSYS_COUNT) {
+		/* maximum number of subsystems already registered! */
+		mutex_unlock(&cgroup_mutex);
+		return -EBUSY;
+	}
+	/* assign ourselves the subsys_id */
+	ss->subsys_id = i;
+	subsys[i] = ss;
+
+	/*
+	 * no ss->create seems to need anything important in the ss struct, so
+	 * this can happen first (i.e. before the rootnode attachment).
+	 */
+	css = ss->create(ss, dummytop);
+	if (IS_ERR(css)) {
+		/* failure case - need to deassign the subsys[] slot. */
+		subsys[i] = NULL;
+		mutex_unlock(&cgroup_mutex);
+		return PTR_ERR(css);
+	}
+
+	list_add(&ss->sibling, &rootnode.subsys_list);
+	ss->root = &rootnode;
+
+	/* our new subsystem will be attached to the dummy hierarchy. */
+	init_cgroup_css(css, ss, dummytop);
+	/* init_idr must be after init_cgroup_css because it sets css->id. */
+	if (ss->use_id) {
+		int ret = cgroup_init_idr(ss, css);
+		if (ret) {
+			dummytop->subsys[ss->subsys_id] = NULL;
+			ss->destroy(ss, dummytop);
+			subsys[i] = NULL;
+			mutex_unlock(&cgroup_mutex);
+			return ret;
+		}
+	}
+
+	/*
+	 * Now we need to entangle the css into the existing css_sets. unlike
+	 * in cgroup_init_subsys, there are now multiple css_sets, so each one
+	 * will need a new pointer to it; done by iterating the css_set_table.
+	 * furthermore, modifying the existing css_sets will corrupt the hash
+	 * table state, so each changed css_set will need its hash recomputed.
+	 * this is all done under the css_set_lock.
+	 */
+	write_lock(&css_set_lock);
+	for (i = 0; i < CSS_SET_TABLE_SIZE; i++) {
+		struct css_set *cg;
+		struct hlist_node *node, *tmp;
+		struct hlist_head *bucket = &css_set_table[i], *new_bucket;
+
+		hlist_for_each_entry_safe(cg, node, tmp, bucket, hlist) {
+			/* skip entries that we already rehashed */
+			if (cg->subsys[ss->subsys_id])
+				continue;
+			/* remove existing entry */
+			hlist_del(&cg->hlist);
+			/* set new value */
+			cg->subsys[ss->subsys_id] = css;
+			/* recompute hash and restore entry */
+			new_bucket = css_set_hash(cg->subsys);
+			hlist_add_head(&cg->hlist, new_bucket);
+		}
+	}
+	write_unlock(&css_set_lock);
+
+	mutex_init(&ss->hierarchy_mutex);
+	lockdep_set_class(&ss->hierarchy_mutex, &ss->subsys_key);
+	ss->active = 1;
+
+	/* success! */
+	mutex_unlock(&cgroup_mutex);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cgroup_load_subsys);
+
+/**
+ * cgroup_unload_subsys: unload a modular subsystem
+ * @ss: the subsystem to unload
+ *
+ * This function should be called in a modular subsystem's exitcall. When this
+ * function is invoked, the refcount on the subsystem's module will be 0, so
+ * the subsystem will not be attached to any hierarchy.
+ */
+void cgroup_unload_subsys(struct cgroup_subsys *ss)
+{
+	struct cg_cgroup_link *link;
+	struct hlist_head *hhead;
+
+	BUG_ON(ss->module == NULL);
+
+	/*
+	 * we shouldn't be called if the subsystem is in use, and the use of
+	 * try_module_get in parse_cgroupfs_options should ensure that it
+	 * doesn't start being used while we're killing it off.
+	 */
+	BUG_ON(ss->root != &rootnode);
+
+	mutex_lock(&cgroup_mutex);
+	/* deassign the subsys_id */
+	BUG_ON(ss->subsys_id < CGROUP_BUILTIN_SUBSYS_COUNT);
+	subsys[ss->subsys_id] = NULL;
+
+	/* remove subsystem from rootnode's list of subsystems */
+	list_del_init(&ss->sibling);
+
+	/*
+	 * disentangle the css from all css_sets attached to the dummytop. as
+	 * in loading, we need to pay our respects to the hashtable gods.
+	 */
+	write_lock(&css_set_lock);
+	list_for_each_entry(link, &dummytop->css_sets, cgrp_link_list) {
+		struct css_set *cg = link->cg;
+
+		hlist_del(&cg->hlist);
+		BUG_ON(!cg->subsys[ss->subsys_id]);
+		cg->subsys[ss->subsys_id] = NULL;
+		hhead = css_set_hash(cg->subsys);
+		hlist_add_head(&cg->hlist, hhead);
+	}
+	write_unlock(&css_set_lock);
+
+	/*
+	 * remove subsystem's css from the dummytop and free it - need to free
+	 * before marking as null because ss->destroy needs the cgrp->subsys
+	 * pointer to find their state. note that this also takes care of
+	 * freeing the css_id.
+	 */
+	ss->destroy(ss, dummytop);
+	dummytop->subsys[ss->subsys_id] = NULL;
+
+	mutex_unlock(&cgroup_mutex);
+}
+EXPORT_SYMBOL_GPL(cgroup_unload_subsys);
+
+/**
+ * cgroup_init_early - cgroup initialization at system boot
+ *
+ * Initialize cgroups at system boot, and initialize any
+ * subsystems that request early init.
+ */
+int __init cgroup_init_early(void)
+{
+	int i;
+	atomic_set(&init_css_set.refcount, 1);
+	INIT_LIST_HEAD(&init_css_set.cg_links);
+	INIT_LIST_HEAD(&init_css_set.tasks);
+	INIT_HLIST_NODE(&init_css_set.hlist);
+	css_set_count = 1;
+	init_cgroup_root(&rootnode);
+	root_count = 1;
+	init_task.cgroups = &init_css_set;
+
+	init_css_set_link.cg = &init_css_set;
+	init_css_set_link.cgrp = dummytop;
+	list_add(&init_css_set_link.cgrp_link_list,
+		 &rootnode.top_cgroup.css_sets);
+	list_add(&init_css_set_link.cg_link_list,
+		 &init_css_set.cg_links);
+
+	for (i = 0; i < CSS_SET_TABLE_SIZE; i++)
+		INIT_HLIST_HEAD(&css_set_table[i]);
+
+	/* at bootup time, we don't worry about modular subsystems */
+	for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+		struct cgroup_subsys *ss = subsys[i];
+
+		BUG_ON(!ss->name);
+		BUG_ON(strlen(ss->name) > MAX_CGROUP_TYPE_NAMELEN);
+		BUG_ON(!ss->create);
+		BUG_ON(!ss->destroy);
+		if (ss->subsys_id != i) {
+			printk(KERN_ERR "cgroup: Subsys %s id == %d\n",
+			       ss->name, ss->subsys_id);
+			BUG();
+		}
+
+		if (ss->early_init)
+			cgroup_init_subsys(ss);
+	}
+	return 0;
+}
+
+/**
+ * cgroup_init - cgroup initialization
+ *
+ * Register cgroup filesystem and /proc file, and initialize
+ * any subsystems that didn't request early init.
+ */
+int __init cgroup_init(void)
+{
+	int err;
+	int i;
+	struct hlist_head *hhead;
+
+	err = bdi_init(&cgroup_backing_dev_info);
+	if (err)
+		return err;
+
+	/* at bootup time, we don't worry about modular subsystems */
+	for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+		struct cgroup_subsys *ss = subsys[i];
+		if (!ss->early_init)
+			cgroup_init_subsys(ss);
+		if (ss->use_id)
+			cgroup_init_idr(ss, init_css_set.subsys[ss->subsys_id]);
+	}
+
+	/* Add init_css_set to the hash table */
+	hhead = css_set_hash(init_css_set.subsys);
+	hlist_add_head(&init_css_set.hlist, hhead);
+	BUG_ON(!init_root_id(&rootnode));
+
+	cgroup_kobj = kobject_create_and_add("cgroup", fs_kobj);
+	if (!cgroup_kobj) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = register_filesystem(&cgroup_fs_type);
+	if (err < 0) {
+		kobject_put(cgroup_kobj);
+		goto out;
+	}
+
+	proc_create("cgroups", 0, NULL, &proc_cgroupstats_operations);
+
+out:
+	if (err)
+		bdi_destroy(&cgroup_backing_dev_info);
+
+	return err;
+}
+
+/*
+ * proc_cgroup_show()
+ *  - Print task's cgroup paths into seq_file, one line for each hierarchy
+ *  - Used for /proc/<pid>/cgroup.
+ *  - No need to task_lock(tsk) on this tsk->cgroup reference, as it
+ *    doesn't really matter if tsk->cgroup changes after we read it,
+ *    and we take cgroup_mutex, keeping cgroup_attach_task() from changing it
+ *    anyway.  No need to check that tsk->cgroup != NULL, thanks to
+ *    the_top_cgroup_hack in cgroup_exit(), which sets an exiting tasks
+ *    cgroup to top_cgroup.
+ */
+
+/* TODO: Use a proper seq_file iterator */
+static int proc_cgroup_show(struct seq_file *m, void *v)
+{
+	struct pid *pid;
+	struct task_struct *tsk;
+	char *buf;
+	int retval;
+	struct cgroupfs_root *root;
+
+	retval = -ENOMEM;
+	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!buf)
+		goto out;
+
+	retval = -ESRCH;
+	pid = m->private;
+	tsk = get_pid_task(pid, PIDTYPE_PID);
+	if (!tsk)
+		goto out_free;
+
+	retval = 0;
+
+	mutex_lock(&cgroup_mutex);
+
+	for_each_active_root(root) {
+		struct cgroup_subsys *ss;
+		struct cgroup *cgrp;
+		int count = 0;
+
+		seq_printf(m, "%d:", root->hierarchy_id);
+		for_each_subsys(root, ss)
+			seq_printf(m, "%s%s", count++ ? "," : "", ss->name);
+		if (strlen(root->name))
+			seq_printf(m, "%sname=%s", count ? "," : "",
+				   root->name);
+		seq_putc(m, ':');
+		cgrp = task_cgroup_from_root(tsk, root);
+		retval = cgroup_path(cgrp, buf, PAGE_SIZE);
+		if (retval < 0)
+			goto out_unlock;
+		seq_puts(m, buf);
+		seq_putc(m, '\n');
+	}
+
+out_unlock:
+	mutex_unlock(&cgroup_mutex);
+	put_task_struct(tsk);
+out_free:
+	kfree(buf);
+out:
+	return retval;
+}
+
+static int cgroup_open(struct inode *inode, struct file *file)
+{
+	struct pid *pid = PROC_I(inode)->pid;
+	return single_open(file, proc_cgroup_show, pid);
+}
+
+const struct file_operations proc_cgroup_operations = {
+	.open		= cgroup_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+/* Display information about each subsystem and each hierarchy */
+static int proc_cgroupstats_show(struct seq_file *m, void *v)
+{
+	int i;
+
+	seq_puts(m, "#subsys_name\thierarchy\tnum_cgroups\tenabled\n");
+	/*
+	 * ideally we don't want subsystems moving around while we do this.
+	 * cgroup_mutex is also necessary to guarantee an atomic snapshot of
+	 * subsys/hierarchy state.
+	 */
+	mutex_lock(&cgroup_mutex);
+	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
+		struct cgroup_subsys *ss = subsys[i];
+		if (ss == NULL)
+			continue;
+		seq_printf(m, "%s\t%d\t%d\t%d\n",
+			   ss->name, ss->root->hierarchy_id,
+			   ss->root->number_of_cgroups, !ss->disabled);
+	}
+	mutex_unlock(&cgroup_mutex);
+	return 0;
+}
+
+static int cgroupstats_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, proc_cgroupstats_show, NULL);
+}
+
+static const struct file_operations proc_cgroupstats_operations = {
+	.open = cgroupstats_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+/**
+ * cgroup_fork - attach newly forked task to its parents cgroup.
+ * @child: pointer to task_struct of forking parent process.
+ *
+ * Description: A task inherits its parent's cgroup at fork().
+ *
+ * A pointer to the shared css_set was automatically copied in
+ * fork.c by dup_task_struct().  However, we ignore that copy, since
+ * it was not made under the protection of RCU, cgroup_mutex or
+ * threadgroup_change_begin(), so it might no longer be a valid
+ * cgroup pointer.  cgroup_attach_task() might have already changed
+ * current->cgroups, allowing the previously referenced cgroup
+ * group to be removed and freed.
+ *
+ * Outside the pointer validity we also need to process the css_set
+ * inheritance between threadgoup_change_begin() and
+ * threadgoup_change_end(), this way there is no leak in any process
+ * wide migration performed by cgroup_attach_proc() that could otherwise
+ * miss a thread because it is too early or too late in the fork stage.
+ *
+ * At the point that cgroup_fork() is called, 'current' is the parent
+ * task, and the passed argument 'child' points to the child task.
+ */
+void cgroup_fork(struct task_struct *child)
+{
+	/*
+	 * We don't need to task_lock() current because current->cgroups
+	 * can't be changed concurrently here. The parent obviously hasn't
+	 * exited and called cgroup_exit(), and we are synchronized against
+	 * cgroup migration through threadgroup_change_begin().
+	 */
+	child->cgroups = current->cgroups;
+	get_css_set(child->cgroups);
+	INIT_LIST_HEAD(&child->cg_list);
+}
+
+/**
+ * cgroup_fork_callbacks - run fork callbacks
+ * @child: the new task
+ *
+ * Called on a new task very soon before adding it to the
+ * tasklist. No need to take any locks since no-one can
+ * be operating on this task.
+ */
+void cgroup_fork_callbacks(struct task_struct *child)
+{
+	if (need_forkexit_callback) {
+		int i;
+		/*
+		 * forkexit callbacks are only supported for builtin
+		 * subsystems, and the builtin section of the subsys array is
+		 * immutable, so we don't need to lock the subsys array here.
+		 */
+		for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+			struct cgroup_subsys *ss = subsys[i];
+			if (ss->fork)
+				ss->fork(ss, child);
+		}
+	}
+}
+
+/**
+ * cgroup_post_fork - called on a new task after adding it to the task list
+ * @child: the task in question
+ *
+ * Adds the task to the list running through its css_set if necessary.
+ * Has to be after the task is visible on the task list in case we race
+ * with the first call to cgroup_iter_start() - to guarantee that the
+ * new task ends up on its list.
+ */
+void cgroup_post_fork(struct task_struct *child)
+{
+	if (use_task_css_set_links) {
+		write_lock(&css_set_lock);
+		if (list_empty(&child->cg_list)) {
+			/*
+			 * It's safe to use child->cgroups without task_lock()
+			 * here because we are protected through
+			 * threadgroup_change_begin() against concurrent
+			 * css_set change in cgroup_task_migrate(). Also
+			 * the task can't exit at that point until
+			 * wake_up_new_task() is called, so we are protected
+			 * against cgroup_exit() setting child->cgroup to
+			 * init_css_set.
+			 */
+			list_add(&child->cg_list, &child->cgroups->tasks);
+		}
+		write_unlock(&css_set_lock);
+	}
+}
+/**
+ * cgroup_exit - detach cgroup from exiting task
+ * @tsk: pointer to task_struct of exiting process
+ * @run_callback: run exit callbacks?
+ *
+ * Description: Detach cgroup from @tsk and release it.
+ *
+ * Note that cgroups marked notify_on_release force every task in
+ * them to take the global cgroup_mutex mutex when exiting.
+ * This could impact scaling on very large systems.  Be reluctant to
+ * use notify_on_release cgroups where very high task exit scaling
+ * is required on large systems.
+ *
+ * the_top_cgroup_hack:
+ *
+ *    Set the exiting tasks cgroup to the root cgroup (top_cgroup).
+ *
+ *    We call cgroup_exit() while the task is still competent to
+ *    handle notify_on_release(), then leave the task attached to the
+ *    root cgroup in each hierarchy for the remainder of its exit.
+ *
+ *    To do this properly, we would increment the reference count on
+ *    top_cgroup, and near the very end of the kernel/exit.c do_exit()
+ *    code we would add a second cgroup function call, to drop that
+ *    reference.  This would just create an unnecessary hot spot on
+ *    the top_cgroup reference count, to no avail.
+ *
+ *    Normally, holding a reference to a cgroup without bumping its
+ *    count is unsafe.   The cgroup could go away, or someone could
+ *    attach us to a different cgroup, decrementing the count on
+ *    the first cgroup that we never incremented.  But in this case,
+ *    top_cgroup isn't going away, and either task has PF_EXITING set,
+ *    which wards off any cgroup_attach_task() attempts, or task is a failed
+ *    fork, never visible to cgroup_attach_task.
+ */
+void cgroup_exit(struct task_struct *tsk, int run_callbacks)
+{
+	struct css_set *cg;
+	int i;
+
+	/*
+	 * Unlink from the css_set task list if necessary.
+	 * Optimistically check cg_list before taking
+	 * css_set_lock
+	 */
+	if (!list_empty(&tsk->cg_list)) {
+		write_lock(&css_set_lock);
+		if (!list_empty(&tsk->cg_list))
+			list_del_init(&tsk->cg_list);
+		write_unlock(&css_set_lock);
+	}
+
+	/* Reassign the task to the init_css_set. */
+	task_lock(tsk);
+	cg = tsk->cgroups;
+	tsk->cgroups = &init_css_set;
+
+	if (run_callbacks && need_forkexit_callback) {
+		/*
+		 * modular subsystems can't use callbacks, so no need to lock
+		 * the subsys array
+		 */
+		for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+			struct cgroup_subsys *ss = subsys[i];
+			if (ss->exit) {
+				struct cgroup *old_cgrp =
+					rcu_dereference_raw(cg->subsys[i])->cgroup;
+				struct cgroup *cgrp = task_cgroup(tsk, i);
+				ss->exit(ss, cgrp, old_cgrp, tsk);
+			}
+		}
+	}
+	task_unlock(tsk);
+
+	if (cg)
+		put_css_set_taskexit(cg);
+}
+
+/**
+ * cgroup_is_descendant - see if @cgrp is a descendant of @task's cgrp
+ * @cgrp: the cgroup in question
+ * @task: the task in question
+ *
+ * See if @cgrp is a descendant of @task's cgroup in the appropriate
+ * hierarchy.
+ *
+ * If we are sending in dummytop, then presumably we are creating
+ * the top cgroup in the subsystem.
+ *
+ * Called only by the ns (nsproxy) cgroup.
+ */
+int cgroup_is_descendant(const struct cgroup *cgrp, struct task_struct *task)
+{
+	int ret;
+	struct cgroup *target;
+
+	if (cgrp == dummytop)
+		return 1;
+
+	target = task_cgroup_from_root(task, cgrp->root);
+	while (cgrp != target && cgrp!= cgrp->top_cgroup)
+		cgrp = cgrp->parent;
+	ret = (cgrp == target);
+	return ret;
+}
+
+static void check_for_release(struct cgroup *cgrp)
+{
+	/* All of these checks rely on RCU to keep the cgroup
+	 * structure alive */
+	if (cgroup_is_releasable(cgrp) && !atomic_read(&cgrp->count)
+	    && list_empty(&cgrp->children) && !cgroup_has_css_refs(cgrp)) {
+		/* Control Group is currently removeable. If it's not
+		 * already queued for a userspace notification, queue
+		 * it now */
+		int need_schedule_work = 0;
+		raw_spin_lock(&release_list_lock);
+		if (!cgroup_is_removed(cgrp) &&
+		    list_empty(&cgrp->release_list)) {
+			list_add(&cgrp->release_list, &release_list);
+			need_schedule_work = 1;
+		}
+		raw_spin_unlock(&release_list_lock);
+		if (need_schedule_work)
+			schedule_work(&release_agent_work);
+	}
+}
+
+/* Caller must verify that the css is not for root cgroup */
+void __css_put(struct cgroup_subsys_state *css, int count)
+{
+	struct cgroup *cgrp = css->cgroup;
+	int val;
+	rcu_read_lock();
+	val = atomic_sub_return(count, &css->refcnt);
+	if (val == 1) {
+		if (notify_on_release(cgrp)) {
+			set_bit(CGRP_RELEASABLE, &cgrp->flags);
+			check_for_release(cgrp);
+		}
+		cgroup_wakeup_rmdir_waiter(cgrp);
+	}
+	rcu_read_unlock();
+	WARN_ON_ONCE(val < 1);
+}
+EXPORT_SYMBOL_GPL(__css_put);
+
+/*
+ * Notify userspace when a cgroup is released, by running the
+ * configured release agent with the name of the cgroup (path
+ * relative to the root of cgroup file system) as the argument.
+ *
+ * Most likely, this user command will try to rmdir this cgroup.
+ *
+ * This races with the possibility that some other task will be
+ * attached to this cgroup before it is removed, or that some other
+ * user task will 'mkdir' a child cgroup of this cgroup.  That's ok.
+ * The presumed 'rmdir' will fail quietly if this cgroup is no longer
+ * unused, and this cgroup will be reprieved from its death sentence,
+ * to continue to serve a useful existence.  Next time it's released,
+ * we will get notified again, if it still has 'notify_on_release' set.
+ *
+ * The final arg to call_usermodehelper() is UMH_WAIT_EXEC, which
+ * means only wait until the task is successfully execve()'d.  The
+ * separate release agent task is forked by call_usermodehelper(),
+ * then control in this thread returns here, without waiting for the
+ * release agent task.  We don't bother to wait because the caller of
+ * this routine has no use for the exit status of the release agent
+ * task, so no sense holding our caller up for that.
+ */
+static void cgroup_release_agent(struct work_struct *work)
+{
+	BUG_ON(work != &release_agent_work);
+	mutex_lock(&cgroup_mutex);
+	raw_spin_lock(&release_list_lock);
+	while (!list_empty(&release_list)) {
+		char *argv[3], *envp[3];
+		int i;
+		char *pathbuf = NULL, *agentbuf = NULL;
+		struct cgroup *cgrp = list_entry(release_list.next,
+						    struct cgroup,
+						    release_list);
+		list_del_init(&cgrp->release_list);
+		raw_spin_unlock(&release_list_lock);
+		pathbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+		if (!pathbuf)
+			goto continue_free;
+		if (cgroup_path(cgrp, pathbuf, PAGE_SIZE) < 0)
+			goto continue_free;
+		agentbuf = kstrdup(cgrp->root->release_agent_path, GFP_KERNEL);
+		if (!agentbuf)
+			goto continue_free;
+
+		i = 0;
+		argv[i++] = agentbuf;
+		argv[i++] = pathbuf;
+		argv[i] = NULL;
+
+		i = 0;
+		/* minimal command environment */
+		envp[i++] = "HOME=/";
+		envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+		envp[i] = NULL;
+
+		/* Drop the lock while we invoke the usermode helper,
+		 * since the exec could involve hitting disk and hence
+		 * be a slow process */
+		mutex_unlock(&cgroup_mutex);
+		call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC);
+		mutex_lock(&cgroup_mutex);
+ continue_free:
+		kfree(pathbuf);
+		kfree(agentbuf);
+		raw_spin_lock(&release_list_lock);
+	}
+	raw_spin_unlock(&release_list_lock);
+	mutex_unlock(&cgroup_mutex);
+}
+
+static int __init cgroup_disable(char *str)
+{
+	int i;
+	char *token;
+
+	while ((token = strsep(&str, ",")) != NULL) {
+		if (!*token)
+			continue;
+		/*
+		 * cgroup_disable, being at boot time, can't know about module
+		 * subsystems, so we don't worry about them.
+		 */
+		for (i = 0; i < CGROUP_BUILTIN_SUBSYS_COUNT; i++) {
+			struct cgroup_subsys *ss = subsys[i];
+
+			if (!strcmp(token, ss->name)) {
+				ss->disabled = 1;
+				printk(KERN_INFO "Disabling %s control group"
+					" subsystem\n", ss->name);
+				break;
+			}
+		}
+	}
+	return 1;
+}
+__setup("cgroup_disable=", cgroup_disable);
+
+/*
+ * Functons for CSS ID.
+ */
+
+/*
+ *To get ID other than 0, this should be called when !cgroup_is_removed().
+ */
+unsigned short css_id(struct cgroup_subsys_state *css)
+{
+	struct css_id *cssid;
+
+	/*
+	 * This css_id() can return correct value when somone has refcnt
+	 * on this or this is under rcu_read_lock(). Once css->id is allocated,
+	 * it's unchanged until freed.
+	 */
+	cssid = rcu_dereference_check(css->id, atomic_read(&css->refcnt));
+
+	if (cssid)
+		return cssid->id;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(css_id);
+
+unsigned short css_depth(struct cgroup_subsys_state *css)
+{
+	struct css_id *cssid;
+
+	cssid = rcu_dereference_check(css->id, atomic_read(&css->refcnt));
+
+	if (cssid)
+		return cssid->depth;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(css_depth);
+
+/**
+ *  css_is_ancestor - test "root" css is an ancestor of "child"
+ * @child: the css to be tested.
+ * @root: the css supporsed to be an ancestor of the child.
+ *
+ * Returns true if "root" is an ancestor of "child" in its hierarchy. Because
+ * this function reads css->id, this use rcu_dereference() and rcu_read_lock().
+ * But, considering usual usage, the csses should be valid objects after test.
+ * Assuming that the caller will do some action to the child if this returns
+ * returns true, the caller must take "child";s reference count.
+ * If "child" is valid object and this returns true, "root" is valid, too.
+ */
+
+bool css_is_ancestor(struct cgroup_subsys_state *child,
+		    const struct cgroup_subsys_state *root)
+{
+	struct css_id *child_id;
+	struct css_id *root_id;
+	bool ret = true;
+
+	rcu_read_lock();
+	child_id  = rcu_dereference(child->id);
+	root_id = rcu_dereference(root->id);
+	if (!child_id
+	    || !root_id
+	    || (child_id->depth < root_id->depth)
+	    || (child_id->stack[root_id->depth] != root_id->id))
+		ret = false;
+	rcu_read_unlock();
+	return ret;
+}
+
+void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css)
+{
+	struct css_id *id = css->id;
+	/* When this is called before css_id initialization, id can be NULL */
+	if (!id)
+		return;
+
+	BUG_ON(!ss->use_id);
+
+	rcu_assign_pointer(id->css, NULL);
+	rcu_assign_pointer(css->id, NULL);
+	write_lock(&ss->id_lock);
+	idr_remove(&ss->idr, id->id);
+	write_unlock(&ss->id_lock);
+	kfree_rcu(id, rcu_head);
+}
+EXPORT_SYMBOL_GPL(free_css_id);
+
+/*
+ * This is called by init or create(). Then, calls to this function are
+ * always serialized (By cgroup_mutex() at create()).
+ */
+
+static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth)
+{
+	struct css_id *newid;
+	int myid, error, size;
+
+	BUG_ON(!ss->use_id);
+
+	size = sizeof(*newid) + sizeof(unsigned short) * (depth + 1);
+	newid = kzalloc(size, GFP_KERNEL);
+	if (!newid)
+		return ERR_PTR(-ENOMEM);
+	/* get id */
+	if (unlikely(!idr_pre_get(&ss->idr, GFP_KERNEL))) {
+		error = -ENOMEM;
+		goto err_out;
+	}
+	write_lock(&ss->id_lock);
+	/* Don't use 0. allocates an ID of 1-65535 */
+	error = idr_get_new_above(&ss->idr, newid, 1, &myid);
+	write_unlock(&ss->id_lock);
+
+	/* Returns error when there are no free spaces for new ID.*/
+	if (error) {
+		error = -ENOSPC;
+		goto err_out;
+	}
+	if (myid > CSS_ID_MAX)
+		goto remove_idr;
+
+	newid->id = myid;
+	newid->depth = depth;
+	return newid;
+remove_idr:
+	error = -ENOSPC;
+	write_lock(&ss->id_lock);
+	idr_remove(&ss->idr, myid);
+	write_unlock(&ss->id_lock);
+err_out:
+	kfree(newid);
+	return ERR_PTR(error);
+
+}
+
+static int __init_or_module cgroup_init_idr(struct cgroup_subsys *ss,
+					    struct cgroup_subsys_state *rootcss)
+{
+	struct css_id *newid;
+
+	rwlock_init(&ss->id_lock);
+	idr_init(&ss->idr);
+
+	newid = get_new_cssid(ss, 0);
+	if (IS_ERR(newid))
+		return PTR_ERR(newid);
+
+	newid->stack[0] = newid->id;
+	newid->css = rootcss;
+	rootcss->id = newid;
+	return 0;
+}
+
+static int alloc_css_id(struct cgroup_subsys *ss, struct cgroup *parent,
+			struct cgroup *child)
+{
+	int subsys_id, i, depth = 0;
+	struct cgroup_subsys_state *parent_css, *child_css;
+	struct css_id *child_id, *parent_id;
+
+	subsys_id = ss->subsys_id;
+	parent_css = parent->subsys[subsys_id];
+	child_css = child->subsys[subsys_id];
+	parent_id = parent_css->id;
+	depth = parent_id->depth + 1;
+
+	child_id = get_new_cssid(ss, depth);
+	if (IS_ERR(child_id))
+		return PTR_ERR(child_id);
+
+	for (i = 0; i < depth; i++)
+		child_id->stack[i] = parent_id->stack[i];
+	child_id->stack[depth] = child_id->id;
+	/*
+	 * child_id->css pointer will be set after this cgroup is available
+	 * see cgroup_populate_dir()
+	 */
+	rcu_assign_pointer(child_css->id, child_id);
+
+	return 0;
+}
+
+/**
+ * css_lookup - lookup css by id
+ * @ss: cgroup subsys to be looked into.
+ * @id: the id
+ *
+ * Returns pointer to cgroup_subsys_state if there is valid one with id.
+ * NULL if not. Should be called under rcu_read_lock()
+ */
+struct cgroup_subsys_state *css_lookup(struct cgroup_subsys *ss, int id)
+{
+	struct css_id *cssid = NULL;
+
+	BUG_ON(!ss->use_id);
+	cssid = idr_find(&ss->idr, id);
+
+	if (unlikely(!cssid))
+		return NULL;
+
+	return rcu_dereference(cssid->css);
+}
+EXPORT_SYMBOL_GPL(css_lookup);
+
+/**
+ * css_get_next - lookup next cgroup under specified hierarchy.
+ * @ss: pointer to subsystem
+ * @id: current position of iteration.
+ * @root: pointer to css. search tree under this.
+ * @foundid: position of found object.
+ *
+ * Search next css under the specified hierarchy of rootid. Calling under
+ * rcu_read_lock() is necessary. Returns NULL if it reaches the end.
+ */
+struct cgroup_subsys_state *
+css_get_next(struct cgroup_subsys *ss, int id,
+	     struct cgroup_subsys_state *root, int *foundid)
+{
+	struct cgroup_subsys_state *ret = NULL;
+	struct css_id *tmp;
+	int tmpid;
+	int rootid = css_id(root);
+	int depth = css_depth(root);
+
+	if (!rootid)
+		return NULL;
+
+	BUG_ON(!ss->use_id);
+	/* fill start point for scan */
+	tmpid = id;
+	while (1) {
+		/*
+		 * scan next entry from bitmap(tree), tmpid is updated after
+		 * idr_get_next().
+		 */
+		read_lock(&ss->id_lock);
+		tmp = idr_get_next(&ss->idr, &tmpid);
+		read_unlock(&ss->id_lock);
+
+		if (!tmp)
+			break;
+		if (tmp->depth >= depth && tmp->stack[depth] == rootid) {
+			ret = rcu_dereference(tmp->css);
+			if (ret) {
+				*foundid = tmpid;
+				break;
+			}
+		}
+		/* continue to scan from next id */
+		tmpid = tmpid + 1;
+	}
+	return ret;
+}
+
+/*
+ * get corresponding css from file open on cgroupfs directory
+ */
+struct cgroup_subsys_state *cgroup_css_from_dir(struct file *f, int id)
+{
+	struct cgroup *cgrp;
+	struct inode *inode;
+	struct cgroup_subsys_state *css;
+
+	inode = f->f_dentry->d_inode;
+	/* check in cgroup filesystem dir */
+	if (inode->i_op != &cgroup_dir_inode_operations)
+		return ERR_PTR(-EBADF);
+
+	if (id < 0 || id >= CGROUP_SUBSYS_COUNT)
+		return ERR_PTR(-EINVAL);
+
+	/* get cgroup */
+	cgrp = __d_cgrp(f->f_dentry);
+	css = cgrp->subsys[id];
+	return css ? css : ERR_PTR(-ENOENT);
+}
+
+#ifdef CONFIG_CGROUP_DEBUG
+static struct cgroup_subsys_state *debug_create(struct cgroup_subsys *ss,
+						   struct cgroup *cont)
+{
+	struct cgroup_subsys_state *css = kzalloc(sizeof(*css), GFP_KERNEL);
+
+	if (!css)
+		return ERR_PTR(-ENOMEM);
+
+	return css;
+}
+
+static void debug_destroy(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+	kfree(cont->subsys[debug_subsys_id]);
+}
+
+static u64 cgroup_refcount_read(struct cgroup *cont, struct cftype *cft)
+{
+	return atomic_read(&cont->count);
+}
+
+static u64 debug_taskcount_read(struct cgroup *cont, struct cftype *cft)
+{
+	return cgroup_task_count(cont);
+}
+
+static u64 current_css_set_read(struct cgroup *cont, struct cftype *cft)
+{
+	return (u64)(unsigned long)current->cgroups;
+}
+
+static u64 current_css_set_refcount_read(struct cgroup *cont,
+					   struct cftype *cft)
+{
+	u64 count;
+
+	rcu_read_lock();
+	count = atomic_read(&current->cgroups->refcount);
+	rcu_read_unlock();
+	return count;
+}
+
+static int current_css_set_cg_links_read(struct cgroup *cont,
+					 struct cftype *cft,
+					 struct seq_file *seq)
+{
+	struct cg_cgroup_link *link;
+	struct css_set *cg;
+
+	read_lock(&css_set_lock);
+	rcu_read_lock();
+	cg = rcu_dereference(current->cgroups);
+	list_for_each_entry(link, &cg->cg_links, cg_link_list) {
+		struct cgroup *c = link->cgrp;
+		const char *name;
+
+		if (c->dentry)
+			name = c->dentry->d_name.name;
+		else
+			name = "?";
+		seq_printf(seq, "Root %d group %s\n",
+			   c->root->hierarchy_id, name);
+	}
+	rcu_read_unlock();
+	read_unlock(&css_set_lock);
+	return 0;
+}
+
+#define MAX_TASKS_SHOWN_PER_CSS 25
+static int cgroup_css_links_read(struct cgroup *cont,
+				 struct cftype *cft,
+				 struct seq_file *seq)
+{
+	struct cg_cgroup_link *link;
+
+	read_lock(&css_set_lock);
+	list_for_each_entry(link, &cont->css_sets, cgrp_link_list) {
+		struct css_set *cg = link->cg;
+		struct task_struct *task;
+		int count = 0;
+		seq_printf(seq, "css_set %p\n", cg);
+		list_for_each_entry(task, &cg->tasks, cg_list) {
+			if (count++ > MAX_TASKS_SHOWN_PER_CSS) {
+				seq_puts(seq, "  ...\n");
+				break;
+			} else {
+				seq_printf(seq, "  task %d\n",
+					   task_pid_vnr(task));
+			}
+		}
+	}
+	read_unlock(&css_set_lock);
+	return 0;
+}
+
+static u64 releasable_read(struct cgroup *cgrp, struct cftype *cft)
+{
+	return test_bit(CGRP_RELEASABLE, &cgrp->flags);
+}
+
+static struct cftype debug_files[] =  {
+	{
+		.name = "cgroup_refcount",
+		.read_u64 = cgroup_refcount_read,
+	},
+	{
+		.name = "taskcount",
+		.read_u64 = debug_taskcount_read,
+	},
+
+	{
+		.name = "current_css_set",
+		.read_u64 = current_css_set_read,
+	},
+
+	{
+		.name = "current_css_set_refcount",
+		.read_u64 = current_css_set_refcount_read,
+	},
+
+	{
+		.name = "current_css_set_cg_links",
+		.read_seq_string = current_css_set_cg_links_read,
+	},
+
+	{
+		.name = "cgroup_css_links",
+		.read_seq_string = cgroup_css_links_read,
+	},
+
+	{
+		.name = "releasable",
+		.read_u64 = releasable_read,
+	},
+};
+
+static int debug_populate(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+	return cgroup_add_files(cont, ss, debug_files,
+				ARRAY_SIZE(debug_files));
+}
+
+struct cgroup_subsys debug_subsys = {
+	.name = "debug",
+	.create = debug_create,
+	.destroy = debug_destroy,
+	.populate = debug_populate,
+	.subsys_id = debug_subsys_id,
+};
+#endif /* CONFIG_CGROUP_DEBUG */
diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c
new file mode 100644
index 00000000000..fc0646b78a6
--- /dev/null
+++ b/kernel/cgroup_freezer.c
@@ -0,0 +1,384 @@
+/*
+ * cgroup_freezer.c -  control group freezer subsystem
+ *
+ * Copyright IBM Corporation, 2007
+ *
+ * Author : Cedric Le Goater <clg@fr.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <linux/cgroup.h>
+#include <linux/fs.h>
+#include <linux/uaccess.h>
+#include <linux/freezer.h>
+#include <linux/seq_file.h>
+
+enum freezer_state {
+	CGROUP_THAWED = 0,
+	CGROUP_FREEZING,
+	CGROUP_FROZEN,
+};
+
+struct freezer {
+	struct cgroup_subsys_state css;
+	enum freezer_state state;
+	spinlock_t lock; /* protects _writes_ to state */
+};
+
+static inline struct freezer *cgroup_freezer(
+		struct cgroup *cgroup)
+{
+	return container_of(
+		cgroup_subsys_state(cgroup, freezer_subsys_id),
+		struct freezer, css);
+}
+
+static inline struct freezer *task_freezer(struct task_struct *task)
+{
+	return container_of(task_subsys_state(task, freezer_subsys_id),
+			    struct freezer, css);
+}
+
+bool cgroup_freezing(struct task_struct *task)
+{
+	enum freezer_state state;
+	bool ret;
+
+	rcu_read_lock();
+	state = task_freezer(task)->state;
+	ret = state == CGROUP_FREEZING || state == CGROUP_FROZEN;
+	rcu_read_unlock();
+
+	return ret;
+}
+
+/*
+ * cgroups_write_string() limits the size of freezer state strings to
+ * CGROUP_LOCAL_BUFFER_SIZE
+ */
+static const char *freezer_state_strs[] = {
+	"THAWED",
+	"FREEZING",
+	"FROZEN",
+};
+
+/*
+ * State diagram
+ * Transitions are caused by userspace writes to the freezer.state file.
+ * The values in parenthesis are state labels. The rest are edge labels.
+ *
+ * (THAWED) --FROZEN--> (FREEZING) --FROZEN--> (FROZEN)
+ *    ^ ^                    |                     |
+ *    | \_______THAWED_______/                     |
+ *    \__________________________THAWED____________/
+ */
+
+struct cgroup_subsys freezer_subsys;
+
+/* Locks taken and their ordering
+ * ------------------------------
+ * cgroup_mutex (AKA cgroup_lock)
+ * freezer->lock
+ * css_set_lock
+ * task->alloc_lock (AKA task_lock)
+ * task->sighand->siglock
+ *
+ * cgroup code forces css_set_lock to be taken before task->alloc_lock
+ *
+ * freezer_create(), freezer_destroy():
+ * cgroup_mutex [ by cgroup core ]
+ *
+ * freezer_can_attach():
+ * cgroup_mutex (held by caller of can_attach)
+ *
+ * freezer_fork() (preserving fork() performance means can't take cgroup_mutex):
+ * freezer->lock
+ *  sighand->siglock (if the cgroup is freezing)
+ *
+ * freezer_read():
+ * cgroup_mutex
+ *  freezer->lock
+ *   write_lock css_set_lock (cgroup iterator start)
+ *    task->alloc_lock
+ *   read_lock css_set_lock (cgroup iterator start)
+ *
+ * freezer_write() (freeze):
+ * cgroup_mutex
+ *  freezer->lock
+ *   write_lock css_set_lock (cgroup iterator start)
+ *    task->alloc_lock
+ *   read_lock css_set_lock (cgroup iterator start)
+ *    sighand->siglock (fake signal delivery inside freeze_task())
+ *
+ * freezer_write() (unfreeze):
+ * cgroup_mutex
+ *  freezer->lock
+ *   write_lock css_set_lock (cgroup iterator start)
+ *    task->alloc_lock
+ *   read_lock css_set_lock (cgroup iterator start)
+ *    task->alloc_lock (inside __thaw_task(), prevents race with refrigerator())
+ *     sighand->siglock
+ */
+static struct cgroup_subsys_state *freezer_create(struct cgroup_subsys *ss,
+						  struct cgroup *cgroup)
+{
+	struct freezer *freezer;
+
+	freezer = kzalloc(sizeof(struct freezer), GFP_KERNEL);
+	if (!freezer)
+		return ERR_PTR(-ENOMEM);
+
+	spin_lock_init(&freezer->lock);
+	freezer->state = CGROUP_THAWED;
+	return &freezer->css;
+}
+
+static void freezer_destroy(struct cgroup_subsys *ss,
+			    struct cgroup *cgroup)
+{
+	struct freezer *freezer = cgroup_freezer(cgroup);
+
+	if (freezer->state != CGROUP_THAWED)
+		atomic_dec(&system_freezing_cnt);
+	kfree(freezer);
+}
+
+/* task is frozen or will freeze immediately when next it gets woken */
+static bool is_task_frozen_enough(struct task_struct *task)
+{
+	return frozen(task) ||
+		(task_is_stopped_or_traced(task) && freezing(task));
+}
+
+/*
+ * The call to cgroup_lock() in the freezer.state write method prevents
+ * a write to that file racing against an attach, and hence the
+ * can_attach() result will remain valid until the attach completes.
+ */
+static int freezer_can_attach(struct cgroup_subsys *ss,
+			      struct cgroup *new_cgroup,
+			      struct cgroup_taskset *tset)
+{
+	struct freezer *freezer;
+	struct task_struct *task;
+
+	/*
+	 * Anything frozen can't move or be moved to/from.
+	 */
+	cgroup_taskset_for_each(task, new_cgroup, tset)
+		if (cgroup_freezing(task))
+			return -EBUSY;
+
+	freezer = cgroup_freezer(new_cgroup);
+	if (freezer->state != CGROUP_THAWED)
+		return -EBUSY;
+
+	return 0;
+}
+
+static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task)
+{
+	struct freezer *freezer;
+
+	/*
+	 * No lock is needed, since the task isn't on tasklist yet,
+	 * so it can't be moved to another cgroup, which means the
+	 * freezer won't be removed and will be valid during this
+	 * function call.  Nevertheless, apply RCU read-side critical
+	 * section to suppress RCU lockdep false positives.
+	 */
+	rcu_read_lock();
+	freezer = task_freezer(task);
+	rcu_read_unlock();
+
+	/*
+	 * The root cgroup is non-freezable, so we can skip the
+	 * following check.
+	 */
+	if (!freezer->css.cgroup->parent)
+		return;
+
+	spin_lock_irq(&freezer->lock);
+	BUG_ON(freezer->state == CGROUP_FROZEN);
+
+	/* Locking avoids race with FREEZING -> THAWED transitions. */
+	if (freezer->state == CGROUP_FREEZING)
+		freeze_task(task);
+	spin_unlock_irq(&freezer->lock);
+}
+
+/*
+ * caller must hold freezer->lock
+ */
+static void update_if_frozen(struct cgroup *cgroup,
+				 struct freezer *freezer)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	unsigned int nfrozen = 0, ntotal = 0;
+	enum freezer_state old_state = freezer->state;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		ntotal++;
+		if (freezing(task) && is_task_frozen_enough(task))
+			nfrozen++;
+	}
+
+	if (old_state == CGROUP_THAWED) {
+		BUG_ON(nfrozen > 0);
+	} else if (old_state == CGROUP_FREEZING) {
+		if (nfrozen == ntotal)
+			freezer->state = CGROUP_FROZEN;
+	} else { /* old_state == CGROUP_FROZEN */
+		BUG_ON(nfrozen != ntotal);
+	}
+
+	cgroup_iter_end(cgroup, &it);
+}
+
+static int freezer_read(struct cgroup *cgroup, struct cftype *cft,
+			struct seq_file *m)
+{
+	struct freezer *freezer;
+	enum freezer_state state;
+
+	if (!cgroup_lock_live_group(cgroup))
+		return -ENODEV;
+
+	freezer = cgroup_freezer(cgroup);
+	spin_lock_irq(&freezer->lock);
+	state = freezer->state;
+	if (state == CGROUP_FREEZING) {
+		/* We change from FREEZING to FROZEN lazily if the cgroup was
+		 * only partially frozen when we exitted write. */
+		update_if_frozen(cgroup, freezer);
+		state = freezer->state;
+	}
+	spin_unlock_irq(&freezer->lock);
+	cgroup_unlock();
+
+	seq_puts(m, freezer_state_strs[state]);
+	seq_putc(m, '\n');
+	return 0;
+}
+
+static int try_to_freeze_cgroup(struct cgroup *cgroup, struct freezer *freezer)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+	unsigned int num_cant_freeze_now = 0;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it))) {
+		if (!freeze_task(task))
+			continue;
+		if (is_task_frozen_enough(task))
+			continue;
+		if (!freezing(task) && !freezer_should_skip(task))
+			num_cant_freeze_now++;
+	}
+	cgroup_iter_end(cgroup, &it);
+
+	return num_cant_freeze_now ? -EBUSY : 0;
+}
+
+static void unfreeze_cgroup(struct cgroup *cgroup, struct freezer *freezer)
+{
+	struct cgroup_iter it;
+	struct task_struct *task;
+
+	cgroup_iter_start(cgroup, &it);
+	while ((task = cgroup_iter_next(cgroup, &it)))
+		__thaw_task(task);
+	cgroup_iter_end(cgroup, &it);
+}
+
+static int freezer_change_state(struct cgroup *cgroup,
+				enum freezer_state goal_state)
+{
+	struct freezer *freezer;
+	int retval = 0;
+
+	freezer = cgroup_freezer(cgroup);
+
+	spin_lock_irq(&freezer->lock);
+
+	update_if_frozen(cgroup, freezer);
+
+	switch (goal_state) {
+	case CGROUP_THAWED:
+		if (freezer->state != CGROUP_THAWED)
+			atomic_dec(&system_freezing_cnt);
+		freezer->state = CGROUP_THAWED;
+		unfreeze_cgroup(cgroup, freezer);
+		break;
+	case CGROUP_FROZEN:
+		if (freezer->state == CGROUP_THAWED)
+			atomic_inc(&system_freezing_cnt);
+		freezer->state = CGROUP_FREEZING;
+		retval = try_to_freeze_cgroup(cgroup, freezer);
+		break;
+	default:
+		BUG();
+	}
+
+	spin_unlock_irq(&freezer->lock);
+
+	return retval;
+}
+
+static int freezer_write(struct cgroup *cgroup,
+			 struct cftype *cft,
+			 const char *buffer)
+{
+	int retval;
+	enum freezer_state goal_state;
+
+	if (strcmp(buffer, freezer_state_strs[CGROUP_THAWED]) == 0)
+		goal_state = CGROUP_THAWED;
+	else if (strcmp(buffer, freezer_state_strs[CGROUP_FROZEN]) == 0)
+		goal_state = CGROUP_FROZEN;
+	else
+		return -EINVAL;
+
+	if (!cgroup_lock_live_group(cgroup))
+		return -ENODEV;
+	retval = freezer_change_state(cgroup, goal_state);
+	cgroup_unlock();
+	return retval;
+}
+
+static struct cftype files[] = {
+	{
+		.name = "state",
+		.read_seq_string = freezer_read,
+		.write_string = freezer_write,
+	},
+};
+
+static int freezer_populate(struct cgroup_subsys *ss, struct cgroup *cgroup)
+{
+	if (!cgroup->parent)
+		return 0;
+	return cgroup_add_files(cgroup, ss, files, ARRAY_SIZE(files));
+}
+
+struct cgroup_subsys freezer_subsys = {
+	.name		= "freezer",
+	.create		= freezer_create,
+	.destroy	= freezer_destroy,
+	.populate	= freezer_populate,
+	.subsys_id	= freezer_subsys_id,
+	.can_attach	= freezer_can_attach,
+	.fork		= freezer_fork,
+};
diff --git a/kernel/compat.c b/kernel/compat.c
new file mode 100644
index 00000000000..f346cedfe24
--- /dev/null
+++ b/kernel/compat.c
@@ -0,0 +1,1164 @@
+/*
+ *  linux/kernel/compat.c
+ *
+ *  Kernel compatibililty routines for e.g. 32 bit syscall support
+ *  on 64 bit kernels.
+ *
+ *  Copyright (C) 2002-2003 Stephen Rothwell, IBM Corporation
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+#include <linux/linkage.h>
+#include <linux/compat.h>
+#include <linux/errno.h>
+#include <linux/time.h>
+#include <linux/signal.h>
+#include <linux/sched.h>	/* for MAX_SCHEDULE_TIMEOUT */
+#include <linux/syscalls.h>
+#include <linux/unistd.h>
+#include <linux/security.h>
+#include <linux/timex.h>
+#include <linux/export.h>
+#include <linux/migrate.h>
+#include <linux/posix-timers.h>
+#include <linux/times.h>
+#include <linux/ptrace.h>
+#include <linux/gfp.h>
+
+#include <asm/uaccess.h>
+
+/*
+ * Note that the native side is already converted to a timespec, because
+ * that's what we want anyway.
+ */
+static int compat_get_timeval(struct timespec *o,
+		struct compat_timeval __user *i)
+{
+	long usec;
+
+	if (get_user(o->tv_sec, &i->tv_sec) ||
+	    get_user(usec, &i->tv_usec))
+		return -EFAULT;
+	o->tv_nsec = usec * 1000;
+	return 0;
+}
+
+static int compat_put_timeval(struct compat_timeval __user *o,
+		struct timeval *i)
+{
+	return (put_user(i->tv_sec, &o->tv_sec) ||
+		put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0;
+}
+
+static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
+{
+	memset(txc, 0, sizeof(struct timex));
+
+	if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
+			__get_user(txc->modes, &utp->modes) ||
+			__get_user(txc->offset, &utp->offset) ||
+			__get_user(txc->freq, &utp->freq) ||
+			__get_user(txc->maxerror, &utp->maxerror) ||
+			__get_user(txc->esterror, &utp->esterror) ||
+			__get_user(txc->status, &utp->status) ||
+			__get_user(txc->constant, &utp->constant) ||
+			__get_user(txc->precision, &utp->precision) ||
+			__get_user(txc->tolerance, &utp->tolerance) ||
+			__get_user(txc->time.tv_sec, &utp->time.tv_sec) ||
+			__get_user(txc->time.tv_usec, &utp->time.tv_usec) ||
+			__get_user(txc->tick, &utp->tick) ||
+			__get_user(txc->ppsfreq, &utp->ppsfreq) ||
+			__get_user(txc->jitter, &utp->jitter) ||
+			__get_user(txc->shift, &utp->shift) ||
+			__get_user(txc->stabil, &utp->stabil) ||
+			__get_user(txc->jitcnt, &utp->jitcnt) ||
+			__get_user(txc->calcnt, &utp->calcnt) ||
+			__get_user(txc->errcnt, &utp->errcnt) ||
+			__get_user(txc->stbcnt, &utp->stbcnt))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)
+{
+	if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
+			__put_user(txc->modes, &utp->modes) ||
+			__put_user(txc->offset, &utp->offset) ||
+			__put_user(txc->freq, &utp->freq) ||
+			__put_user(txc->maxerror, &utp->maxerror) ||
+			__put_user(txc->esterror, &utp->esterror) ||
+			__put_user(txc->status, &utp->status) ||
+			__put_user(txc->constant, &utp->constant) ||
+			__put_user(txc->precision, &utp->precision) ||
+			__put_user(txc->tolerance, &utp->tolerance) ||
+			__put_user(txc->time.tv_sec, &utp->time.tv_sec) ||
+			__put_user(txc->time.tv_usec, &utp->time.tv_usec) ||
+			__put_user(txc->tick, &utp->tick) ||
+			__put_user(txc->ppsfreq, &utp->ppsfreq) ||
+			__put_user(txc->jitter, &utp->jitter) ||
+			__put_user(txc->shift, &utp->shift) ||
+			__put_user(txc->stabil, &utp->stabil) ||
+			__put_user(txc->jitcnt, &utp->jitcnt) ||
+			__put_user(txc->calcnt, &utp->calcnt) ||
+			__put_user(txc->errcnt, &utp->errcnt) ||
+			__put_user(txc->stbcnt, &utp->stbcnt) ||
+			__put_user(txc->tai, &utp->tai))
+		return -EFAULT;
+	return 0;
+}
+
+asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
+		struct timezone __user *tz)
+{
+	if (tv) {
+		struct timeval ktv;
+		do_gettimeofday(&ktv);
+		if (compat_put_timeval(tv, &ktv))
+			return -EFAULT;
+	}
+	if (tz) {
+		if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
+			return -EFAULT;
+	}
+
+	return 0;
+}
+
+asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv,
+		struct timezone __user *tz)
+{
+	struct timespec kts;
+	struct timezone ktz;
+
+	if (tv) {
+		if (compat_get_timeval(&kts, tv))
+			return -EFAULT;
+	}
+	if (tz) {
+		if (copy_from_user(&ktz, tz, sizeof(ktz)))
+			return -EFAULT;
+	}
+
+	return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
+}
+
+int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
+{
+	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
+			__get_user(ts->tv_sec, &cts->tv_sec) ||
+			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
+}
+
+int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
+{
+	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
+			__put_user(ts->tv_sec, &cts->tv_sec) ||
+			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
+}
+EXPORT_SYMBOL_GPL(put_compat_timespec);
+
+static long compat_nanosleep_restart(struct restart_block *restart)
+{
+	struct compat_timespec __user *rmtp;
+	struct timespec rmt;
+	mm_segment_t oldfs;
+	long ret;
+
+	restart->nanosleep.rmtp = (struct timespec __user *) &rmt;
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	ret = hrtimer_nanosleep_restart(restart);
+	set_fs(oldfs);
+
+	if (ret) {
+		rmtp = restart->nanosleep.compat_rmtp;
+
+		if (rmtp && put_compat_timespec(&rmt, rmtp))
+			return -EFAULT;
+	}
+
+	return ret;
+}
+
+asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
+				     struct compat_timespec __user *rmtp)
+{
+	struct timespec tu, rmt;
+	mm_segment_t oldfs;
+	long ret;
+
+	if (get_compat_timespec(&tu, rqtp))
+		return -EFAULT;
+
+	if (!timespec_valid(&tu))
+		return -EINVAL;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	ret = hrtimer_nanosleep(&tu,
+				rmtp ? (struct timespec __user *)&rmt : NULL,
+				HRTIMER_MODE_REL, CLOCK_MONOTONIC);
+	set_fs(oldfs);
+
+	if (ret) {
+		struct restart_block *restart
+			= &current_thread_info()->restart_block;
+
+		restart->fn = compat_nanosleep_restart;
+		restart->nanosleep.compat_rmtp = rmtp;
+
+		if (rmtp && put_compat_timespec(&rmt, rmtp))
+			return -EFAULT;
+	}
+
+	return ret;
+}
+
+static inline long get_compat_itimerval(struct itimerval *o,
+		struct compat_itimerval __user *i)
+{
+	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
+		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
+		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
+		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
+		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
+}
+
+static inline long put_compat_itimerval(struct compat_itimerval __user *o,
+		struct itimerval *i)
+{
+	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
+		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
+		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
+		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
+		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
+}
+
+asmlinkage long compat_sys_getitimer(int which,
+		struct compat_itimerval __user *it)
+{
+	struct itimerval kit;
+	int error;
+
+	error = do_getitimer(which, &kit);
+	if (!error && put_compat_itimerval(it, &kit))
+		error = -EFAULT;
+	return error;
+}
+
+asmlinkage long compat_sys_setitimer(int which,
+		struct compat_itimerval __user *in,
+		struct compat_itimerval __user *out)
+{
+	struct itimerval kin, kout;
+	int error;
+
+	if (in) {
+		if (get_compat_itimerval(&kin, in))
+			return -EFAULT;
+	} else
+		memset(&kin, 0, sizeof(kin));
+
+	error = do_setitimer(which, &kin, out ? &kout : NULL);
+	if (error || !out)
+		return error;
+	if (put_compat_itimerval(out, &kout))
+		return -EFAULT;
+	return 0;
+}
+
+static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
+{
+	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
+}
+
+asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
+{
+	if (tbuf) {
+		struct tms tms;
+		struct compat_tms tmp;
+
+		do_sys_times(&tms);
+		/* Convert our struct tms to the compat version. */
+		tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
+		tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
+		tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
+		tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
+		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
+			return -EFAULT;
+	}
+	force_successful_syscall_return();
+	return compat_jiffies_to_clock_t(jiffies);
+}
+
+#ifdef __ARCH_WANT_SYS_SIGPENDING
+
+/*
+ * Assumption: old_sigset_t and compat_old_sigset_t are both
+ * types that can be passed to put_user()/get_user().
+ */
+
+asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
+{
+	old_sigset_t s;
+	long ret;
+	mm_segment_t old_fs = get_fs();
+
+	set_fs(KERNEL_DS);
+	ret = sys_sigpending((old_sigset_t __user *) &s);
+	set_fs(old_fs);
+	if (ret == 0)
+		ret = put_user(s, set);
+	return ret;
+}
+
+#endif
+
+#ifdef __ARCH_WANT_SYS_SIGPROCMASK
+
+asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *set,
+		compat_old_sigset_t __user *oset)
+{
+	old_sigset_t s;
+	long ret;
+	mm_segment_t old_fs;
+
+	if (set && get_user(s, set))
+		return -EFAULT;
+	old_fs = get_fs();
+	set_fs(KERNEL_DS);
+	ret = sys_sigprocmask(how,
+			      set ? (old_sigset_t __user *) &s : NULL,
+			      oset ? (old_sigset_t __user *) &s : NULL);
+	set_fs(old_fs);
+	if (ret == 0)
+		if (oset)
+			ret = put_user(s, oset);
+	return ret;
+}
+
+#endif
+
+asmlinkage long compat_sys_setrlimit(unsigned int resource,
+		struct compat_rlimit __user *rlim)
+{
+	struct rlimit r;
+
+	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
+	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
+	    __get_user(r.rlim_max, &rlim->rlim_max))
+		return -EFAULT;
+
+	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
+		r.rlim_cur = RLIM_INFINITY;
+	if (r.rlim_max == COMPAT_RLIM_INFINITY)
+		r.rlim_max = RLIM_INFINITY;
+	return do_prlimit(current, resource, &r, NULL);
+}
+
+#ifdef COMPAT_RLIM_OLD_INFINITY
+
+asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
+		struct compat_rlimit __user *rlim)
+{
+	struct rlimit r;
+	int ret;
+	mm_segment_t old_fs = get_fs();
+
+	set_fs(KERNEL_DS);
+	ret = sys_old_getrlimit(resource, &r);
+	set_fs(old_fs);
+
+	if (!ret) {
+		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
+			r.rlim_cur = COMPAT_RLIM_INFINITY;
+		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
+			r.rlim_max = COMPAT_RLIM_INFINITY;
+
+		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
+		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
+		    __put_user(r.rlim_max, &rlim->rlim_max))
+			return -EFAULT;
+	}
+	return ret;
+}
+
+#endif
+
+asmlinkage long compat_sys_getrlimit(unsigned int resource,
+		struct compat_rlimit __user *rlim)
+{
+	struct rlimit r;
+	int ret;
+
+	ret = do_prlimit(current, resource, NULL, &r);
+	if (!ret) {
+		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
+			r.rlim_cur = COMPAT_RLIM_INFINITY;
+		if (r.rlim_max > COMPAT_RLIM_INFINITY)
+			r.rlim_max = COMPAT_RLIM_INFINITY;
+
+		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
+		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
+		    __put_user(r.rlim_max, &rlim->rlim_max))
+			return -EFAULT;
+	}
+	return ret;
+}
+
+int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
+{
+	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
+	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
+	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
+	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
+	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
+	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
+	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
+	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
+	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
+	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
+	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
+	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
+	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
+	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
+	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
+	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
+	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
+	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
+	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
+		return -EFAULT;
+	return 0;
+}
+
+asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
+{
+	struct rusage r;
+	int ret;
+	mm_segment_t old_fs = get_fs();
+
+	set_fs(KERNEL_DS);
+	ret = sys_getrusage(who, (struct rusage __user *) &r);
+	set_fs(old_fs);
+
+	if (ret)
+		return ret;
+
+	if (put_compat_rusage(&r, ru))
+		return -EFAULT;
+
+	return 0;
+}
+
+asmlinkage long
+compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
+	struct compat_rusage __user *ru)
+{
+	if (!ru) {
+		return sys_wait4(pid, stat_addr, options, NULL);
+	} else {
+		struct rusage r;
+		int ret;
+		unsigned int status;
+		mm_segment_t old_fs = get_fs();
+
+		set_fs (KERNEL_DS);
+		ret = sys_wait4(pid,
+				(stat_addr ?
+				 (unsigned int __user *) &status : NULL),
+				options, (struct rusage __user *) &r);
+		set_fs (old_fs);
+
+		if (ret > 0) {
+			if (put_compat_rusage(&r, ru))
+				return -EFAULT;
+			if (stat_addr && put_user(status, stat_addr))
+				return -EFAULT;
+		}
+		return ret;
+	}
+}
+
+asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
+		struct compat_siginfo __user *uinfo, int options,
+		struct compat_rusage __user *uru)
+{
+	siginfo_t info;
+	struct rusage ru;
+	long ret;
+	mm_segment_t old_fs = get_fs();
+
+	memset(&info, 0, sizeof(info));
+
+	set_fs(KERNEL_DS);
+	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
+			 uru ? (struct rusage __user *)&ru : NULL);
+	set_fs(old_fs);
+
+	if ((ret < 0) || (info.si_signo == 0))
+		return ret;
+
+	if (uru) {
+		ret = put_compat_rusage(&ru, uru);
+		if (ret)
+			return ret;
+	}
+
+	BUG_ON(info.si_code & __SI_MASK);
+	info.si_code |= __SI_CHLD;
+	return copy_siginfo_to_user32(uinfo, &info);
+}
+
+static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
+				    unsigned len, struct cpumask *new_mask)
+{
+	unsigned long *k;
+
+	if (len < cpumask_size())
+		memset(new_mask, 0, cpumask_size());
+	else if (len > cpumask_size())
+		len = cpumask_size();
+
+	k = cpumask_bits(new_mask);
+	return compat_get_bitmap(k, user_mask_ptr, len * 8);
+}
+
+asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
+					     unsigned int len,
+					     compat_ulong_t __user *user_mask_ptr)
+{
+	cpumask_var_t new_mask;
+	int retval;
+
+	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
+	if (retval)
+		goto out;
+
+	retval = sched_setaffinity(pid, new_mask);
+out:
+	free_cpumask_var(new_mask);
+	return retval;
+}
+
+asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
+					     compat_ulong_t __user *user_mask_ptr)
+{
+	int ret;
+	cpumask_var_t mask;
+
+	if ((len * BITS_PER_BYTE) < nr_cpu_ids)
+		return -EINVAL;
+	if (len & (sizeof(compat_ulong_t)-1))
+		return -EINVAL;
+
+	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	ret = sched_getaffinity(pid, mask);
+	if (ret == 0) {
+		size_t retlen = min_t(size_t, len, cpumask_size());
+
+		if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
+			ret = -EFAULT;
+		else
+			ret = retlen;
+	}
+	free_cpumask_var(mask);
+
+	return ret;
+}
+
+int get_compat_itimerspec(struct itimerspec *dst,
+			  const struct compat_itimerspec __user *src)
+{
+	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
+	    get_compat_timespec(&dst->it_value, &src->it_value))
+		return -EFAULT;
+	return 0;
+}
+
+int put_compat_itimerspec(struct compat_itimerspec __user *dst,
+			  const struct itimerspec *src)
+{
+	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
+	    put_compat_timespec(&src->it_value, &dst->it_value))
+		return -EFAULT;
+	return 0;
+}
+
+long compat_sys_timer_create(clockid_t which_clock,
+			struct compat_sigevent __user *timer_event_spec,
+			timer_t __user *created_timer_id)
+{
+	struct sigevent __user *event = NULL;
+
+	if (timer_event_spec) {
+		struct sigevent kevent;
+
+		event = compat_alloc_user_space(sizeof(*event));
+		if (get_compat_sigevent(&kevent, timer_event_spec) ||
+		    copy_to_user(event, &kevent, sizeof(*event)))
+			return -EFAULT;
+	}
+
+	return sys_timer_create(which_clock, event, created_timer_id);
+}
+
+long compat_sys_timer_settime(timer_t timer_id, int flags,
+			  struct compat_itimerspec __user *new,
+			  struct compat_itimerspec __user *old)
+{
+	long err;
+	mm_segment_t oldfs;
+	struct itimerspec newts, oldts;
+
+	if (!new)
+		return -EINVAL;
+	if (get_compat_itimerspec(&newts, new))
+		return -EFAULT;
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = sys_timer_settime(timer_id, flags,
+				(struct itimerspec __user *) &newts,
+				(struct itimerspec __user *) &oldts);
+	set_fs(oldfs);
+	if (!err && old && put_compat_itimerspec(old, &oldts))
+		return -EFAULT;
+	return err;
+}
+
+long compat_sys_timer_gettime(timer_t timer_id,
+		struct compat_itimerspec __user *setting)
+{
+	long err;
+	mm_segment_t oldfs;
+	struct itimerspec ts;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = sys_timer_gettime(timer_id,
+				(struct itimerspec __user *) &ts);
+	set_fs(oldfs);
+	if (!err && put_compat_itimerspec(setting, &ts))
+		return -EFAULT;
+	return err;
+}
+
+long compat_sys_clock_settime(clockid_t which_clock,
+		struct compat_timespec __user *tp)
+{
+	long err;
+	mm_segment_t oldfs;
+	struct timespec ts;
+
+	if (get_compat_timespec(&ts, tp))
+		return -EFAULT;
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = sys_clock_settime(which_clock,
+				(struct timespec __user *) &ts);
+	set_fs(oldfs);
+	return err;
+}
+
+long compat_sys_clock_gettime(clockid_t which_clock,
+		struct compat_timespec __user *tp)
+{
+	long err;
+	mm_segment_t oldfs;
+	struct timespec ts;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = sys_clock_gettime(which_clock,
+				(struct timespec __user *) &ts);
+	set_fs(oldfs);
+	if (!err && put_compat_timespec(&ts, tp))
+		return -EFAULT;
+	return err;
+}
+
+long compat_sys_clock_adjtime(clockid_t which_clock,
+		struct compat_timex __user *utp)
+{
+	struct timex txc;
+	mm_segment_t oldfs;
+	int err, ret;
+
+	err = compat_get_timex(&txc, utp);
+	if (err)
+		return err;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
+	set_fs(oldfs);
+
+	err = compat_put_timex(utp, &txc);
+	if (err)
+		return err;
+
+	return ret;
+}
+
+long compat_sys_clock_getres(clockid_t which_clock,
+		struct compat_timespec __user *tp)
+{
+	long err;
+	mm_segment_t oldfs;
+	struct timespec ts;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = sys_clock_getres(which_clock,
+			       (struct timespec __user *) &ts);
+	set_fs(oldfs);
+	if (!err && tp && put_compat_timespec(&ts, tp))
+		return -EFAULT;
+	return err;
+}
+
+static long compat_clock_nanosleep_restart(struct restart_block *restart)
+{
+	long err;
+	mm_segment_t oldfs;
+	struct timespec tu;
+	struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
+
+	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = clock_nanosleep_restart(restart);
+	set_fs(oldfs);
+
+	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
+	    put_compat_timespec(&tu, rmtp))
+		return -EFAULT;
+
+	if (err == -ERESTART_RESTARTBLOCK) {
+		restart->fn = compat_clock_nanosleep_restart;
+		restart->nanosleep.compat_rmtp = rmtp;
+	}
+	return err;
+}
+
+long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
+			    struct compat_timespec __user *rqtp,
+			    struct compat_timespec __user *rmtp)
+{
+	long err;
+	mm_segment_t oldfs;
+	struct timespec in, out;
+	struct restart_block *restart;
+
+	if (get_compat_timespec(&in, rqtp))
+		return -EFAULT;
+
+	oldfs = get_fs();
+	set_fs(KERNEL_DS);
+	err = sys_clock_nanosleep(which_clock, flags,
+				  (struct timespec __user *) &in,
+				  (struct timespec __user *) &out);
+	set_fs(oldfs);
+
+	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
+	    put_compat_timespec(&out, rmtp))
+		return -EFAULT;
+
+	if (err == -ERESTART_RESTARTBLOCK) {
+		restart = &current_thread_info()->restart_block;
+		restart->fn = compat_clock_nanosleep_restart;
+		restart->nanosleep.compat_rmtp = rmtp;
+	}
+	return err;
+}
+
+/*
+ * We currently only need the following fields from the sigevent
+ * structure: sigev_value, sigev_signo, sig_notify and (sometimes
+ * sigev_notify_thread_id).  The others are handled in user mode.
+ * We also assume that copying sigev_value.sival_int is sufficient
+ * to keep all the bits of sigev_value.sival_ptr intact.
+ */
+int get_compat_sigevent(struct sigevent *event,
+		const struct compat_sigevent __user *u_event)
+{
+	memset(event, 0, sizeof(*event));
+	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
+		__get_user(event->sigev_value.sival_int,
+			&u_event->sigev_value.sival_int) ||
+		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
+		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
+		__get_user(event->sigev_notify_thread_id,
+			&u_event->sigev_notify_thread_id))
+		? -EFAULT : 0;
+}
+
+long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
+		       unsigned long bitmap_size)
+{
+	int i, j;
+	unsigned long m;
+	compat_ulong_t um;
+	unsigned long nr_compat_longs;
+
+	/* align bitmap up to nearest compat_long_t boundary */
+	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
+
+	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
+		return -EFAULT;
+
+	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
+
+	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
+		m = 0;
+
+		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
+			/*
+			 * We dont want to read past the end of the userspace
+			 * bitmap. We must however ensure the end of the
+			 * kernel bitmap is zeroed.
+			 */
+			if (nr_compat_longs-- > 0) {
+				if (__get_user(um, umask))
+					return -EFAULT;
+			} else {
+				um = 0;
+			}
+
+			umask++;
+			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
+		}
+		*mask++ = m;
+	}
+
+	return 0;
+}
+
+long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
+		       unsigned long bitmap_size)
+{
+	int i, j;
+	unsigned long m;
+	compat_ulong_t um;
+	unsigned long nr_compat_longs;
+
+	/* align bitmap up to nearest compat_long_t boundary */
+	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
+
+	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
+		return -EFAULT;
+
+	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
+
+	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
+		m = *mask++;
+
+		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
+			um = m;
+
+			/*
+			 * We dont want to write past the end of the userspace
+			 * bitmap.
+			 */
+			if (nr_compat_longs-- > 0) {
+				if (__put_user(um, umask))
+					return -EFAULT;
+			}
+
+			umask++;
+			m >>= 4*sizeof(um);
+			m >>= 4*sizeof(um);
+		}
+	}
+
+	return 0;
+}
+
+void
+sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
+{
+	switch (_NSIG_WORDS) {
+	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
+	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
+	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
+	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
+	}
+}
+EXPORT_SYMBOL_GPL(sigset_from_compat);
+
+asmlinkage long
+compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
+		struct compat_siginfo __user *uinfo,
+		struct compat_timespec __user *uts, compat_size_t sigsetsize)
+{
+	compat_sigset_t s32;
+	sigset_t s;
+	struct timespec t;
+	siginfo_t info;
+	long ret;
+
+	if (sigsetsize != sizeof(sigset_t))
+		return -EINVAL;
+
+	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
+		return -EFAULT;
+	sigset_from_compat(&s, &s32);
+
+	if (uts) {
+		if (get_compat_timespec(&t, uts))
+			return -EFAULT;
+	}
+
+	ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
+
+	if (ret > 0 && uinfo) {
+		if (copy_siginfo_to_user32(uinfo, &info))
+			ret = -EFAULT;
+	}
+
+	return ret;
+
+}
+
+asmlinkage long
+compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig,
+			     struct compat_siginfo __user *uinfo)
+{
+	siginfo_t info;
+
+	if (copy_siginfo_from_user32(&info, uinfo))
+		return -EFAULT;
+	return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
+}
+
+#ifdef __ARCH_WANT_COMPAT_SYS_TIME
+
+/* compat_time_t is a 32 bit "long" and needs to get converted. */
+
+asmlinkage long compat_sys_time(compat_time_t __user * tloc)
+{
+	compat_time_t i;
+	struct timeval tv;
+
+	do_gettimeofday(&tv);
+	i = tv.tv_sec;
+
+	if (tloc) {
+		if (put_user(i,tloc))
+			return -EFAULT;
+	}
+	force_successful_syscall_return();
+	return i;
+}
+
+asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
+{
+	struct timespec tv;
+	int err;
+
+	if (get_user(tv.tv_sec, tptr))
+		return -EFAULT;
+
+	tv.tv_nsec = 0;
+
+	err = security_settime(&tv, NULL);
+	if (err)
+		return err;
+
+	do_settimeofday(&tv);
+	return 0;
+}
+
+#endif /* __ARCH_WANT_COMPAT_SYS_TIME */
+
+#ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
+asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
+{
+	sigset_t newset;
+	compat_sigset_t newset32;
+
+	/* XXX: Don't preclude handling different sized sigset_t's.  */
+	if (sigsetsize != sizeof(sigset_t))
+		return -EINVAL;
+
+	if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
+		return -EFAULT;
+	sigset_from_compat(&newset, &newset32);
+	sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+	current->saved_sigmask = current->blocked;
+	set_current_blocked(&newset);
+
+	current->state = TASK_INTERRUPTIBLE;
+	schedule();
+	set_restore_sigmask();
+	return -ERESTARTNOHAND;
+}
+#endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
+
+asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
+{
+	struct timex txc;
+	int err, ret;
+
+	err = compat_get_timex(&txc, utp);
+	if (err)
+		return err;
+
+	ret = do_adjtimex(&txc);
+
+	err = compat_put_timex(utp, &txc);
+	if (err)
+		return err;
+
+	return ret;
+}
+
+#ifdef CONFIG_NUMA
+asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
+		compat_uptr_t __user *pages32,
+		const int __user *nodes,
+		int __user *status,
+		int flags)
+{
+	const void __user * __user *pages;
+	int i;
+
+	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
+	for (i = 0; i < nr_pages; i++) {
+		compat_uptr_t p;
+
+		if (get_user(p, pages32 + i) ||
+			put_user(compat_ptr(p), pages + i))
+			return -EFAULT;
+	}
+	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
+}
+
+asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
+			compat_ulong_t maxnode,
+			const compat_ulong_t __user *old_nodes,
+			const compat_ulong_t __user *new_nodes)
+{
+	unsigned long __user *old = NULL;
+	unsigned long __user *new = NULL;
+	nodemask_t tmp_mask;
+	unsigned long nr_bits;
+	unsigned long size;
+
+	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
+	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
+	if (old_nodes) {
+		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
+			return -EFAULT;
+		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
+		if (new_nodes)
+			new = old + size / sizeof(unsigned long);
+		if (copy_to_user(old, nodes_addr(tmp_mask), size))
+			return -EFAULT;
+	}
+	if (new_nodes) {
+		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
+			return -EFAULT;
+		if (new == NULL)
+			new = compat_alloc_user_space(size);
+		if (copy_to_user(new, nodes_addr(tmp_mask), size))
+			return -EFAULT;
+	}
+	return sys_migrate_pages(pid, nr_bits + 1, old, new);
+}
+#endif
+
+struct compat_sysinfo {
+	s32 uptime;
+	u32 loads[3];
+	u32 totalram;
+	u32 freeram;
+	u32 sharedram;
+	u32 bufferram;
+	u32 totalswap;
+	u32 freeswap;
+	u16 procs;
+	u16 pad;
+	u32 totalhigh;
+	u32 freehigh;
+	u32 mem_unit;
+	char _f[20-2*sizeof(u32)-sizeof(int)];
+};
+
+asmlinkage long
+compat_sys_sysinfo(struct compat_sysinfo __user *info)
+{
+	struct sysinfo s;
+
+	do_sysinfo(&s);
+
+	/* Check to see if any memory value is too large for 32-bit and scale
+	 *  down if needed
+	 */
+	if ((s.totalram >> 32) || (s.totalswap >> 32)) {
+		int bitcount = 0;
+
+		while (s.mem_unit < PAGE_SIZE) {
+			s.mem_unit <<= 1;
+			bitcount++;
+		}
+
+		s.totalram >>= bitcount;
+		s.freeram >>= bitcount;
+		s.sharedram >>= bitcount;
+		s.bufferram >>= bitcount;
+		s.totalswap >>= bitcount;
+		s.freeswap >>= bitcount;
+		s.totalhigh >>= bitcount;
+		s.freehigh >>= bitcount;
+	}
+
+	if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
+	    __put_user (s.uptime, &info->uptime) ||
+	    __put_user (s.loads[0], &info->loads[0]) ||
+	    __put_user (s.loads[1], &info->loads[1]) ||
+	    __put_user (s.loads[2], &info->loads[2]) ||
+	    __put_user (s.totalram, &info->totalram) ||
+	    __put_user (s.freeram, &info->freeram) ||
+	    __put_user (s.sharedram, &info->sharedram) ||
+	    __put_user (s.bufferram, &info->bufferram) ||
+	    __put_user (s.totalswap, &info->totalswap) ||
+	    __put_user (s.freeswap, &info->freeswap) ||
+	    __put_user (s.procs, &info->procs) ||
+	    __put_user (s.totalhigh, &info->totalhigh) ||
+	    __put_user (s.freehigh, &info->freehigh) ||
+	    __put_user (s.mem_unit, &info->mem_unit))
+		return -EFAULT;
+
+	return 0;
+}
+
+/*
+ * Allocate user-space memory for the duration of a single system call,
+ * in order to marshall parameters inside a compat thunk.
+ */
+void __user *compat_alloc_user_space(unsigned long len)
+{
+	void __user *ptr;
+
+	/* If len would occupy more than half of the entire compat space... */
+	if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
+		return NULL;
+
+	ptr = arch_compat_alloc_user_space(len);
+
+	if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
+		return NULL;
+
+	return ptr;
+}
+EXPORT_SYMBOL_GPL(compat_alloc_user_space);
diff --git a/kernel/configs.c b/kernel/configs.c
new file mode 100644
index 00000000000..42e8fa075ee
--- /dev/null
+++ b/kernel/configs.c
@@ -0,0 +1,99 @@
+/*
+ * kernel/configs.c
+ * Echo the kernel .config file used to build the kernel
+ *
+ * Copyright (C) 2002 Khalid Aziz <khalid_aziz@hp.com>
+ * Copyright (C) 2002 Randy Dunlap <rdunlap@xenotime.net>
+ * Copyright (C) 2002 Al Stone <ahs3@fc.hp.com>
+ * Copyright (C) 2002 Hewlett-Packard Company
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+
+/**************************************************/
+/* the actual current config file                 */
+
+/*
+ * Define kernel_config_data and kernel_config_data_size, which contains the
+ * wrapped and compressed configuration file.  The file is first compressed
+ * with gzip and then bounded by two eight byte magic numbers to allow
+ * extraction from a binary kernel image:
+ *
+ *   IKCFG_ST
+ *   <image>
+ *   IKCFG_ED
+ */
+#define MAGIC_START	"IKCFG_ST"
+#define MAGIC_END	"IKCFG_ED"
+#include "config_data.h"
+
+
+#define MAGIC_SIZE (sizeof(MAGIC_START) - 1)
+#define kernel_config_data_size \
+	(sizeof(kernel_config_data) - 1 - MAGIC_SIZE * 2)
+
+#ifdef CONFIG_IKCONFIG_PROC
+
+static ssize_t
+ikconfig_read_current(struct file *file, char __user *buf,
+		      size_t len, loff_t * offset)
+{
+	return simple_read_from_buffer(buf, len, offset,
+				       kernel_config_data + MAGIC_SIZE,
+				       kernel_config_data_size);
+}
+
+static const struct file_operations ikconfig_file_ops = {
+	.owner = THIS_MODULE,
+	.read = ikconfig_read_current,
+	.llseek = default_llseek,
+};
+
+static int __init ikconfig_init(void)
+{
+	struct proc_dir_entry *entry;
+
+	/* create the current config file */
+	entry = proc_create("config.gz", S_IFREG | S_IRUGO, NULL,
+			    &ikconfig_file_ops);
+	if (!entry)
+		return -ENOMEM;
+
+	entry->size = kernel_config_data_size;
+
+	return 0;
+}
+
+static void __exit ikconfig_cleanup(void)
+{
+	remove_proc_entry("config.gz", NULL);
+}
+
+module_init(ikconfig_init);
+module_exit(ikconfig_cleanup);
+
+#endif /* CONFIG_IKCONFIG_PROC */
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Randy Dunlap");
+MODULE_DESCRIPTION("Echo the kernel .config file used to build the kernel");
diff --git a/kernel/cpu.c b/kernel/cpu.c
new file mode 100644
index 00000000000..2060c6e5702
--- /dev/null
+++ b/kernel/cpu.c
@@ -0,0 +1,670 @@
+/* CPU control.
+ * (C) 2001, 2002, 2003, 2004 Rusty Russell
+ *
+ * This code is licenced under the GPL.
+ */
+#include <linux/proc_fs.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/notifier.h>
+#include <linux/sched.h>
+#include <linux/unistd.h>
+#include <linux/cpu.h>
+#include <linux/export.h>
+#include <linux/kthread.h>
+#include <linux/stop_machine.h>
+#include <linux/mutex.h>
+#include <linux/gfp.h>
+#include <linux/suspend.h>
+
+#ifdef CONFIG_SMP
+/* Serializes the updates to cpu_online_mask, cpu_present_mask */
+static DEFINE_MUTEX(cpu_add_remove_lock);
+
+/*
+ * The following two API's must be used when attempting
+ * to serialize the updates to cpu_online_mask, cpu_present_mask.
+ */
+void cpu_maps_update_begin(void)
+{
+	mutex_lock(&cpu_add_remove_lock);
+}
+
+void cpu_maps_update_done(void)
+{
+	mutex_unlock(&cpu_add_remove_lock);
+}
+
+static RAW_NOTIFIER_HEAD(cpu_chain);
+
+/* If set, cpu_up and cpu_down will return -EBUSY and do nothing.
+ * Should always be manipulated under cpu_add_remove_lock
+ */
+static int cpu_hotplug_disabled;
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static struct {
+	struct task_struct *active_writer;
+	struct mutex lock; /* Synchronizes accesses to refcount, */
+	/*
+	 * Also blocks the new readers during
+	 * an ongoing cpu hotplug operation.
+	 */
+	int refcount;
+} cpu_hotplug = {
+	.active_writer = NULL,
+	.lock = __MUTEX_INITIALIZER(cpu_hotplug.lock),
+	.refcount = 0,
+};
+
+void get_online_cpus(void)
+{
+	might_sleep();
+	if (cpu_hotplug.active_writer == current)
+		return;
+	mutex_lock(&cpu_hotplug.lock);
+	cpu_hotplug.refcount++;
+	mutex_unlock(&cpu_hotplug.lock);
+
+}
+EXPORT_SYMBOL_GPL(get_online_cpus);
+
+void put_online_cpus(void)
+{
+	if (cpu_hotplug.active_writer == current)
+		return;
+	mutex_lock(&cpu_hotplug.lock);
+	if (!--cpu_hotplug.refcount && unlikely(cpu_hotplug.active_writer))
+		wake_up_process(cpu_hotplug.active_writer);
+	mutex_unlock(&cpu_hotplug.lock);
+
+}
+EXPORT_SYMBOL_GPL(put_online_cpus);
+
+/*
+ * This ensures that the hotplug operation can begin only when the
+ * refcount goes to zero.
+ *
+ * Note that during a cpu-hotplug operation, the new readers, if any,
+ * will be blocked by the cpu_hotplug.lock
+ *
+ * Since cpu_hotplug_begin() is always called after invoking
+ * cpu_maps_update_begin(), we can be sure that only one writer is active.
+ *
+ * Note that theoretically, there is a possibility of a livelock:
+ * - Refcount goes to zero, last reader wakes up the sleeping
+ *   writer.
+ * - Last reader unlocks the cpu_hotplug.lock.
+ * - A new reader arrives at this moment, bumps up the refcount.
+ * - The writer acquires the cpu_hotplug.lock finds the refcount
+ *   non zero and goes to sleep again.
+ *
+ * However, this is very difficult to achieve in practice since
+ * get_online_cpus() not an api which is called all that often.
+ *
+ */
+static void cpu_hotplug_begin(void)
+{
+	cpu_hotplug.active_writer = current;
+
+	for (;;) {
+		mutex_lock(&cpu_hotplug.lock);
+		if (likely(!cpu_hotplug.refcount))
+			break;
+		__set_current_state(TASK_UNINTERRUPTIBLE);
+		mutex_unlock(&cpu_hotplug.lock);
+		schedule();
+	}
+}
+
+static void cpu_hotplug_done(void)
+{
+	cpu_hotplug.active_writer = NULL;
+	mutex_unlock(&cpu_hotplug.lock);
+}
+
+#else /* #if CONFIG_HOTPLUG_CPU */
+static void cpu_hotplug_begin(void) {}
+static void cpu_hotplug_done(void) {}
+#endif	/* #else #if CONFIG_HOTPLUG_CPU */
+
+/* Need to know about CPUs going up/down? */
+int __ref register_cpu_notifier(struct notifier_block *nb)
+{
+	int ret;
+	cpu_maps_update_begin();
+	ret = raw_notifier_chain_register(&cpu_chain, nb);
+	cpu_maps_update_done();
+	return ret;
+}
+
+static int __cpu_notify(unsigned long val, void *v, int nr_to_call,
+			int *nr_calls)
+{
+	int ret;
+
+	ret = __raw_notifier_call_chain(&cpu_chain, val, v, nr_to_call,
+					nr_calls);
+
+	return notifier_to_errno(ret);
+}
+
+static int cpu_notify(unsigned long val, void *v)
+{
+	return __cpu_notify(val, v, -1, NULL);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static void cpu_notify_nofail(unsigned long val, void *v)
+{
+	BUG_ON(cpu_notify(val, v));
+}
+EXPORT_SYMBOL(register_cpu_notifier);
+
+void __ref unregister_cpu_notifier(struct notifier_block *nb)
+{
+	cpu_maps_update_begin();
+	raw_notifier_chain_unregister(&cpu_chain, nb);
+	cpu_maps_update_done();
+}
+EXPORT_SYMBOL(unregister_cpu_notifier);
+
+static inline void check_for_tasks(int cpu)
+{
+	struct task_struct *p;
+
+	write_lock_irq(&tasklist_lock);
+	for_each_process(p) {
+		if (task_cpu(p) == cpu && p->state == TASK_RUNNING &&
+		    (p->utime || p->stime))
+			printk(KERN_WARNING "Task %s (pid = %d) is on cpu %d "
+				"(state = %ld, flags = %x)\n",
+				p->comm, task_pid_nr(p), cpu,
+				p->state, p->flags);
+	}
+	write_unlock_irq(&tasklist_lock);
+}
+
+struct take_cpu_down_param {
+	unsigned long mod;
+	void *hcpu;
+};
+
+/* Take this CPU down. */
+static int __ref take_cpu_down(void *_param)
+{
+	struct take_cpu_down_param *param = _param;
+	int err;
+
+	/* Ensure this CPU doesn't handle any more interrupts. */
+	err = __cpu_disable();
+	if (err < 0)
+		return err;
+
+	cpu_notify(CPU_DYING | param->mod, param->hcpu);
+	return 0;
+}
+
+/* Requires cpu_add_remove_lock to be held */
+static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
+{
+	int err, nr_calls = 0;
+	void *hcpu = (void *)(long)cpu;
+	unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
+	struct take_cpu_down_param tcd_param = {
+		.mod = mod,
+		.hcpu = hcpu,
+	};
+
+	if (num_online_cpus() == 1)
+		return -EBUSY;
+
+	if (!cpu_online(cpu))
+		return -EINVAL;
+
+	cpu_hotplug_begin();
+
+	err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls);
+	if (err) {
+		nr_calls--;
+		__cpu_notify(CPU_DOWN_FAILED | mod, hcpu, nr_calls, NULL);
+		printk("%s: attempt to take down CPU %u failed\n",
+				__func__, cpu);
+		goto out_release;
+	}
+
+	err = __stop_machine(take_cpu_down, &tcd_param, cpumask_of(cpu));
+	if (err) {
+		/* CPU didn't die: tell everyone.  Can't complain. */
+		cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
+
+		goto out_release;
+	}
+	BUG_ON(cpu_online(cpu));
+
+	/*
+	 * The migration_call() CPU_DYING callback will have removed all
+	 * runnable tasks from the cpu, there's only the idle task left now
+	 * that the migration thread is done doing the stop_machine thing.
+	 *
+	 * Wait for the stop thread to go away.
+	 */
+	while (!idle_cpu(cpu))
+		cpu_relax();
+
+	/* This actually kills the CPU. */
+	__cpu_die(cpu);
+
+	/* CPU is completely dead: tell everyone.  Too late to complain. */
+	cpu_notify_nofail(CPU_DEAD | mod, hcpu);
+
+	check_for_tasks(cpu);
+
+out_release:
+	cpu_hotplug_done();
+	if (!err)
+		cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu);
+	return err;
+}
+
+int __ref cpu_down(unsigned int cpu)
+{
+	int err;
+
+	cpu_maps_update_begin();
+
+	if (cpu_hotplug_disabled) {
+		err = -EBUSY;
+		goto out;
+	}
+
+	err = _cpu_down(cpu, 0);
+
+out:
+	cpu_maps_update_done();
+	return err;
+}
+EXPORT_SYMBOL(cpu_down);
+#endif /*CONFIG_HOTPLUG_CPU*/
+
+/* Requires cpu_add_remove_lock to be held */
+static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
+{
+	int ret, nr_calls = 0;
+	void *hcpu = (void *)(long)cpu;
+	unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0;
+
+	if (cpu_online(cpu) || !cpu_present(cpu))
+		return -EINVAL;
+
+	cpu_hotplug_begin();
+	ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
+	if (ret) {
+		nr_calls--;
+		printk(KERN_WARNING "%s: attempt to bring up CPU %u failed\n",
+				__func__, cpu);
+		goto out_notify;
+	}
+
+	/* Arch-specific enabling code. */
+	ret = __cpu_up(cpu);
+	if (ret != 0)
+		goto out_notify;
+	BUG_ON(!cpu_online(cpu));
+
+	/* Now call notifier in preparation. */
+	cpu_notify(CPU_ONLINE | mod, hcpu);
+
+out_notify:
+	if (ret != 0)
+		__cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
+	cpu_hotplug_done();
+
+	return ret;
+}
+
+int __cpuinit cpu_up(unsigned int cpu)
+{
+	int err = 0;
+
+#ifdef	CONFIG_MEMORY_HOTPLUG
+	int nid;
+	pg_data_t	*pgdat;
+#endif
+
+	if (!cpu_possible(cpu)) {
+		printk(KERN_ERR "can't online cpu %d because it is not "
+			"configured as may-hotadd at boot time\n", cpu);
+#if defined(CONFIG_IA64)
+		printk(KERN_ERR "please check additional_cpus= boot "
+				"parameter\n");
+#endif
+		return -EINVAL;
+	}
+
+#ifdef	CONFIG_MEMORY_HOTPLUG
+	nid = cpu_to_node(cpu);
+	if (!node_online(nid)) {
+		err = mem_online_node(nid);
+		if (err)
+			return err;
+	}
+
+	pgdat = NODE_DATA(nid);
+	if (!pgdat) {
+		printk(KERN_ERR
+			"Can't online cpu %d due to NULL pgdat\n", cpu);
+		return -ENOMEM;
+	}
+
+	if (pgdat->node_zonelists->_zonerefs->zone == NULL) {
+		mutex_lock(&zonelists_mutex);
+		build_all_zonelists(NULL);
+		mutex_unlock(&zonelists_mutex);
+	}
+#endif
+
+	cpu_maps_update_begin();
+
+	if (cpu_hotplug_disabled) {
+		err = -EBUSY;
+		goto out;
+	}
+
+	err = _cpu_up(cpu, 0);
+
+out:
+	cpu_maps_update_done();
+	return err;
+}
+EXPORT_SYMBOL_GPL(cpu_up);
+
+#ifdef CONFIG_PM_SLEEP_SMP
+static cpumask_var_t frozen_cpus;
+
+void __weak arch_disable_nonboot_cpus_begin(void)
+{
+}
+
+void __weak arch_disable_nonboot_cpus_end(void)
+{
+}
+
+int disable_nonboot_cpus(void)
+{
+	int cpu, first_cpu, error = 0;
+
+	cpu_maps_update_begin();
+	first_cpu = cpumask_first(cpu_online_mask);
+	/*
+	 * We take down all of the non-boot CPUs in one shot to avoid races
+	 * with the userspace trying to use the CPU hotplug at the same time
+	 */
+	cpumask_clear(frozen_cpus);
+	arch_disable_nonboot_cpus_begin();
+
+	printk("Disabling non-boot CPUs ...\n");
+	for_each_online_cpu(cpu) {
+		if (cpu == first_cpu)
+			continue;
+		error = _cpu_down(cpu, 1);
+		if (!error)
+			cpumask_set_cpu(cpu, frozen_cpus);
+		else {
+			printk(KERN_ERR "Error taking CPU%d down: %d\n",
+				cpu, error);
+			break;
+		}
+	}
+
+	arch_disable_nonboot_cpus_end();
+
+	if (!error) {
+		BUG_ON(num_online_cpus() > 1);
+		/* Make sure the CPUs won't be enabled by someone else */
+		cpu_hotplug_disabled = 1;
+	} else {
+		printk(KERN_ERR "Non-boot CPUs are not disabled\n");
+	}
+	cpu_maps_update_done();
+	return error;
+}
+
+void __weak arch_enable_nonboot_cpus_begin(void)
+{
+}
+
+void __weak arch_enable_nonboot_cpus_end(void)
+{
+}
+
+void __ref enable_nonboot_cpus(void)
+{
+	int cpu, error;
+
+	/* Allow everyone to use the CPU hotplug again */
+	cpu_maps_update_begin();
+	cpu_hotplug_disabled = 0;
+	if (cpumask_empty(frozen_cpus))
+		goto out;
+
+	printk(KERN_INFO "Enabling non-boot CPUs ...\n");
+
+	arch_enable_nonboot_cpus_begin();
+
+	for_each_cpu(cpu, frozen_cpus) {
+		error = _cpu_up(cpu, 1);
+		if (!error) {
+			printk(KERN_INFO "CPU%d is up\n", cpu);
+			continue;
+		}
+		printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);
+	}
+
+	arch_enable_nonboot_cpus_end();
+
+	cpumask_clear(frozen_cpus);
+out:
+	cpu_maps_update_done();
+}
+
+static int __init alloc_frozen_cpus(void)
+{
+	if (!alloc_cpumask_var(&frozen_cpus, GFP_KERNEL|__GFP_ZERO))
+		return -ENOMEM;
+	return 0;
+}
+core_initcall(alloc_frozen_cpus);
+
+/*
+ * Prevent regular CPU hotplug from racing with the freezer, by disabling CPU
+ * hotplug when tasks are about to be frozen. Also, don't allow the freezer
+ * to continue until any currently running CPU hotplug operation gets
+ * completed.
+ * To modify the 'cpu_hotplug_disabled' flag, we need to acquire the
+ * 'cpu_add_remove_lock'. And this same lock is also taken by the regular
+ * CPU hotplug path and released only after it is complete. Thus, we
+ * (and hence the freezer) will block here until any currently running CPU
+ * hotplug operation gets completed.
+ */
+void cpu_hotplug_disable_before_freeze(void)
+{
+	cpu_maps_update_begin();
+	cpu_hotplug_disabled = 1;
+	cpu_maps_update_done();
+}
+
+
+/*
+ * When tasks have been thawed, re-enable regular CPU hotplug (which had been
+ * disabled while beginning to freeze tasks).
+ */
+void cpu_hotplug_enable_after_thaw(void)
+{
+	cpu_maps_update_begin();
+	cpu_hotplug_disabled = 0;
+	cpu_maps_update_done();
+}
+
+/*
+ * When callbacks for CPU hotplug notifications are being executed, we must
+ * ensure that the state of the system with respect to the tasks being frozen
+ * or not, as reported by the notification, remains unchanged *throughout the
+ * duration* of the execution of the callbacks.
+ * Hence we need to prevent the freezer from racing with regular CPU hotplug.
+ *
+ * This synchronization is implemented by mutually excluding regular CPU
+ * hotplug and Suspend/Hibernate call paths by hooking onto the Suspend/
+ * Hibernate notifications.
+ */
+static int
+cpu_hotplug_pm_callback(struct notifier_block *nb,
+			unsigned long action, void *ptr)
+{
+	switch (action) {
+
+	case PM_SUSPEND_PREPARE:
+	case PM_HIBERNATION_PREPARE:
+		cpu_hotplug_disable_before_freeze();
+		break;
+
+	case PM_POST_SUSPEND:
+	case PM_POST_HIBERNATION:
+		cpu_hotplug_enable_after_thaw();
+		break;
+
+	default:
+		return NOTIFY_DONE;
+	}
+
+	return NOTIFY_OK;
+}
+
+
+static int __init cpu_hotplug_pm_sync_init(void)
+{
+	pm_notifier(cpu_hotplug_pm_callback, 0);
+	return 0;
+}
+core_initcall(cpu_hotplug_pm_sync_init);
+
+#endif /* CONFIG_PM_SLEEP_SMP */
+
+/**
+ * notify_cpu_starting(cpu) - call the CPU_STARTING notifiers
+ * @cpu: cpu that just started
+ *
+ * This function calls the cpu_chain notifiers with CPU_STARTING.
+ * It must be called by the arch code on the new cpu, before the new cpu
+ * enables interrupts and before the "boot" cpu returns from __cpu_up().
+ */
+void __cpuinit notify_cpu_starting(unsigned int cpu)
+{
+	unsigned long val = CPU_STARTING;
+
+#ifdef CONFIG_PM_SLEEP_SMP
+	if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus))
+		val = CPU_STARTING_FROZEN;
+#endif /* CONFIG_PM_SLEEP_SMP */
+	cpu_notify(val, (void *)(long)cpu);
+}
+
+#endif /* CONFIG_SMP */
+
+/*
+ * cpu_bit_bitmap[] is a special, "compressed" data structure that
+ * represents all NR_CPUS bits binary values of 1<<nr.
+ *
+ * It is used by cpumask_of() to get a constant address to a CPU
+ * mask value that has a single bit set only.
+ */
+
+/* cpu_bit_bitmap[0] is empty - so we can back into it */
+#define MASK_DECLARE_1(x)	[x+1][0] = (1UL << (x))
+#define MASK_DECLARE_2(x)	MASK_DECLARE_1(x), MASK_DECLARE_1(x+1)
+#define MASK_DECLARE_4(x)	MASK_DECLARE_2(x), MASK_DECLARE_2(x+2)
+#define MASK_DECLARE_8(x)	MASK_DECLARE_4(x), MASK_DECLARE_4(x+4)
+
+const unsigned long cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)] = {
+
+	MASK_DECLARE_8(0),	MASK_DECLARE_8(8),
+	MASK_DECLARE_8(16),	MASK_DECLARE_8(24),
+#if BITS_PER_LONG > 32
+	MASK_DECLARE_8(32),	MASK_DECLARE_8(40),
+	MASK_DECLARE_8(48),	MASK_DECLARE_8(56),
+#endif
+};
+EXPORT_SYMBOL_GPL(cpu_bit_bitmap);
+
+const DECLARE_BITMAP(cpu_all_bits, NR_CPUS) = CPU_BITS_ALL;
+EXPORT_SYMBOL(cpu_all_bits);
+
+#ifdef CONFIG_INIT_ALL_POSSIBLE
+static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly
+	= CPU_BITS_ALL;
+#else
+static DECLARE_BITMAP(cpu_possible_bits, CONFIG_NR_CPUS) __read_mostly;
+#endif
+const struct cpumask *const cpu_possible_mask = to_cpumask(cpu_possible_bits);
+EXPORT_SYMBOL(cpu_possible_mask);
+
+static DECLARE_BITMAP(cpu_online_bits, CONFIG_NR_CPUS) __read_mostly;
+const struct cpumask *const cpu_online_mask = to_cpumask(cpu_online_bits);
+EXPORT_SYMBOL(cpu_online_mask);
+
+static DECLARE_BITMAP(cpu_present_bits, CONFIG_NR_CPUS) __read_mostly;
+const struct cpumask *const cpu_present_mask = to_cpumask(cpu_present_bits);
+EXPORT_SYMBOL(cpu_present_mask);
+
+static DECLARE_BITMAP(cpu_active_bits, CONFIG_NR_CPUS) __read_mostly;
+const struct cpumask *const cpu_active_mask = to_cpumask(cpu_active_bits);
+EXPORT_SYMBOL(cpu_active_mask);
+
+void set_cpu_possible(unsigned int cpu, bool possible)
+{
+	if (possible)
+		cpumask_set_cpu(cpu, to_cpumask(cpu_possible_bits));
+	else
+		cpumask_clear_cpu(cpu, to_cpumask(cpu_possible_bits));
+}
+
+void set_cpu_present(unsigned int cpu, bool present)
+{
+	if (present)
+		cpumask_set_cpu(cpu, to_cpumask(cpu_present_bits));
+	else
+		cpumask_clear_cpu(cpu, to_cpumask(cpu_present_bits));
+}
+
+void set_cpu_online(unsigned int cpu, bool online)
+{
+	if (online)
+		cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits));
+	else
+		cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits));
+}
+
+void set_cpu_active(unsigned int cpu, bool active)
+{
+	if (active)
+		cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits));
+	else
+		cpumask_clear_cpu(cpu, to_cpumask(cpu_active_bits));
+}
+
+void init_cpu_present(const struct cpumask *src)
+{
+	cpumask_copy(to_cpumask(cpu_present_bits), src);
+}
+
+void init_cpu_possible(const struct cpumask *src)
+{
+	cpumask_copy(to_cpumask(cpu_possible_bits), src);
+}
+
+void init_cpu_online(const struct cpumask *src)
+{
+	cpumask_copy(to_cpumask(cpu_online_bits), src);
+}
diff --git a/kernel/cpu_pm.c b/kernel/cpu_pm.c
new file mode 100644
index 00000000000..249152e1530
--- /dev/null
+++ b/kernel/cpu_pm.c
@@ -0,0 +1,233 @@
+/*
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * Author:
+ *	Colin Cross <ccross@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/cpu_pm.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/spinlock.h>
+#include <linux/syscore_ops.h>
+
+static DEFINE_RWLOCK(cpu_pm_notifier_lock);
+static RAW_NOTIFIER_HEAD(cpu_pm_notifier_chain);
+
+static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls)
+{
+	int ret;
+
+	ret = __raw_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL,
+		nr_to_call, nr_calls);
+
+	return notifier_to_errno(ret);
+}
+
+/**
+ * cpu_pm_register_notifier - register a driver with cpu_pm
+ * @nb: notifier block to register
+ *
+ * Add a driver to a list of drivers that are notified about
+ * CPU and CPU cluster low power entry and exit.
+ *
+ * This function may sleep, and has the same return conditions as
+ * raw_notifier_chain_register.
+ */
+int cpu_pm_register_notifier(struct notifier_block *nb)
+{
+	unsigned long flags;
+	int ret;
+
+	write_lock_irqsave(&cpu_pm_notifier_lock, flags);
+	ret = raw_notifier_chain_register(&cpu_pm_notifier_chain, nb);
+	write_unlock_irqrestore(&cpu_pm_notifier_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_register_notifier);
+
+/**
+ * cpu_pm_unregister_notifier - unregister a driver with cpu_pm
+ * @nb: notifier block to be unregistered
+ *
+ * Remove a driver from the CPU PM notifier list.
+ *
+ * This function may sleep, and has the same return conditions as
+ * raw_notifier_chain_unregister.
+ */
+int cpu_pm_unregister_notifier(struct notifier_block *nb)
+{
+	unsigned long flags;
+	int ret;
+
+	write_lock_irqsave(&cpu_pm_notifier_lock, flags);
+	ret = raw_notifier_chain_unregister(&cpu_pm_notifier_chain, nb);
+	write_unlock_irqrestore(&cpu_pm_notifier_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_unregister_notifier);
+
+/**
+ * cpm_pm_enter - CPU low power entry notifier
+ *
+ * Notifies listeners that a single CPU is entering a low power state that may
+ * cause some blocks in the same power domain as the cpu to reset.
+ *
+ * Must be called on the affected CPU with interrupts disabled.  Platform is
+ * responsible for ensuring that cpu_pm_enter is not called twice on the same
+ * CPU before cpu_pm_exit is called. Notified drivers can include VFP
+ * co-processor, interrupt controller and it's PM extensions, local CPU
+ * timers context save/restore which shouldn't be interrupted. Hence it
+ * must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_pm_enter(void)
+{
+	int nr_calls;
+	int ret = 0;
+
+	read_lock(&cpu_pm_notifier_lock);
+	ret = cpu_pm_notify(CPU_PM_ENTER, -1, &nr_calls);
+	if (ret)
+		/*
+		 * Inform listeners (nr_calls - 1) about failure of CPU PM
+		 * PM entry who are notified earlier to prepare for it.
+		 */
+		cpu_pm_notify(CPU_PM_ENTER_FAILED, nr_calls - 1, NULL);
+	read_unlock(&cpu_pm_notifier_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_enter);
+
+/**
+ * cpm_pm_exit - CPU low power exit notifier
+ *
+ * Notifies listeners that a single CPU is exiting a low power state that may
+ * have caused some blocks in the same power domain as the cpu to reset.
+ *
+ * Notified drivers can include VFP co-processor, interrupt controller
+ * and it's PM extensions, local CPU timers context save/restore which
+ * shouldn't be interrupted. Hence it must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_pm_exit(void)
+{
+	int ret;
+
+	read_lock(&cpu_pm_notifier_lock);
+	ret = cpu_pm_notify(CPU_PM_EXIT, -1, NULL);
+	read_unlock(&cpu_pm_notifier_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_exit);
+
+/**
+ * cpm_cluster_pm_enter - CPU cluster low power entry notifier
+ *
+ * Notifies listeners that all cpus in a power domain are entering a low power
+ * state that may cause some blocks in the same power domain to reset.
+ *
+ * Must be called after cpu_pm_enter has been called on all cpus in the power
+ * domain, and before cpu_pm_exit has been called on any cpu in the power
+ * domain. Notified drivers can include VFP co-processor, interrupt controller
+ * and it's PM extensions, local CPU timers context save/restore which
+ * shouldn't be interrupted. Hence it must be called with interrupts disabled.
+ *
+ * Must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_cluster_pm_enter(void)
+{
+	int nr_calls;
+	int ret = 0;
+
+	read_lock(&cpu_pm_notifier_lock);
+	ret = cpu_pm_notify(CPU_CLUSTER_PM_ENTER, -1, &nr_calls);
+	if (ret)
+		/*
+		 * Inform listeners (nr_calls - 1) about failure of CPU cluster
+		 * PM entry who are notified earlier to prepare for it.
+		 */
+		cpu_pm_notify(CPU_CLUSTER_PM_ENTER_FAILED, nr_calls - 1, NULL);
+	read_unlock(&cpu_pm_notifier_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_cluster_pm_enter);
+
+/**
+ * cpm_cluster_pm_exit - CPU cluster low power exit notifier
+ *
+ * Notifies listeners that all cpus in a power domain are exiting form a
+ * low power state that may have caused some blocks in the same power domain
+ * to reset.
+ *
+ * Must be called after cpu_pm_exit has been called on all cpus in the power
+ * domain, and before cpu_pm_exit has been called on any cpu in the power
+ * domain. Notified drivers can include VFP co-processor, interrupt controller
+ * and it's PM extensions, local CPU timers context save/restore which
+ * shouldn't be interrupted. Hence it must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_cluster_pm_exit(void)
+{
+	int ret;
+
+	read_lock(&cpu_pm_notifier_lock);
+	ret = cpu_pm_notify(CPU_CLUSTER_PM_EXIT, -1, NULL);
+	read_unlock(&cpu_pm_notifier_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_cluster_pm_exit);
+
+#ifdef CONFIG_PM
+static int cpu_pm_suspend(void)
+{
+	int ret;
+
+	ret = cpu_pm_enter();
+	if (ret)
+		return ret;
+
+	ret = cpu_cluster_pm_enter();
+	return ret;
+}
+
+static void cpu_pm_resume(void)
+{
+	cpu_cluster_pm_exit();
+	cpu_pm_exit();
+}
+
+static struct syscore_ops cpu_pm_syscore_ops = {
+	.suspend = cpu_pm_suspend,
+	.resume = cpu_pm_resume,
+};
+
+static int cpu_pm_init(void)
+{
+	register_syscore_ops(&cpu_pm_syscore_ops);
+	return 0;
+}
+core_initcall(cpu_pm_init);
+#endif
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
new file mode 100644
index 00000000000..a09ac2b9a66
--- /dev/null
+++ b/kernel/cpuset.c
@@ -0,0 +1,2636 @@
+/*
+ *  kernel/cpuset.c
+ *
+ *  Processor and Memory placement constraints for sets of tasks.
+ *
+ *  Copyright (C) 2003 BULL SA.
+ *  Copyright (C) 2004-2007 Silicon Graphics, Inc.
+ *  Copyright (C) 2006 Google, Inc
+ *
+ *  Portions derived from Patrick Mochel's sysfs code.
+ *  sysfs is Copyright (c) 2001-3 Patrick Mochel
+ *
+ *  2003-10-10 Written by Simon Derr.
+ *  2003-10-22 Updates by Stephen Hemminger.
+ *  2004 May-July Rework by Paul Jackson.
+ *  2006 Rework by Paul Menage to use generic cgroups
+ *  2008 Rework of the scheduler domains and CPU hotplug handling
+ *       by Max Krasnyansky
+ *
+ *  This file is subject to the terms and conditions of the GNU General Public
+ *  License.  See the file COPYING in the main directory of the Linux
+ *  distribution for more details.
+ */
+
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/cpuset.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/kmod.h>
+#include <linux/list.h>
+#include <linux/mempolicy.h>
+#include <linux/mm.h>
+#include <linux/memory.h>
+#include <linux/export.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/pagemap.h>
+#include <linux/proc_fs.h>
+#include <linux/rcupdate.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/security.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/time.h>
+#include <linux/backing-dev.h>
+#include <linux/sort.h>
+
+#include <asm/uaccess.h>
+#include <linux/atomic.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/cgroup.h>
+
+/*
+ * Workqueue for cpuset related tasks.
+ *
+ * Using kevent workqueue may cause deadlock when memory_migrate
+ * is set. So we create a separate workqueue thread for cpuset.
+ */
+static struct workqueue_struct *cpuset_wq;
+
+/*
+ * Tracks how many cpusets are currently defined in system.
+ * When there is only one cpuset (the root cpuset) we can
+ * short circuit some hooks.
+ */
+int number_of_cpusets __read_mostly;
+
+/* Forward declare cgroup structures */
+struct cgroup_subsys cpuset_subsys;
+struct cpuset;
+
+/* See "Frequency meter" comments, below. */
+
+struct fmeter {
+	int cnt;		/* unprocessed events count */
+	int val;		/* most recent output value */
+	time_t time;		/* clock (secs) when val computed */
+	spinlock_t lock;	/* guards read or write of above */
+};
+
+struct cpuset {
+	struct cgroup_subsys_state css;
+
+	unsigned long flags;		/* "unsigned long" so bitops work */
+	cpumask_var_t cpus_allowed;	/* CPUs allowed to tasks in cpuset */
+	nodemask_t mems_allowed;	/* Memory Nodes allowed to tasks */
+
+	struct cpuset *parent;		/* my parent */
+
+	struct fmeter fmeter;		/* memory_pressure filter */
+
+	/* partition number for rebuild_sched_domains() */
+	int pn;
+
+	/* for custom sched domain */
+	int relax_domain_level;
+
+	/* used for walking a cpuset hierarchy */
+	struct list_head stack_list;
+};
+
+/* Retrieve the cpuset for a cgroup */
+static inline struct cpuset *cgroup_cs(struct cgroup *cont)
+{
+	return container_of(cgroup_subsys_state(cont, cpuset_subsys_id),
+			    struct cpuset, css);
+}
+
+/* Retrieve the cpuset for a task */
+static inline struct cpuset *task_cs(struct task_struct *task)
+{
+	return container_of(task_subsys_state(task, cpuset_subsys_id),
+			    struct cpuset, css);
+}
+
+#ifdef CONFIG_NUMA
+static inline bool task_has_mempolicy(struct task_struct *task)
+{
+	return task->mempolicy;
+}
+#else
+static inline bool task_has_mempolicy(struct task_struct *task)
+{
+	return false;
+}
+#endif
+
+
+/* bits in struct cpuset flags field */
+typedef enum {
+	CS_CPU_EXCLUSIVE,
+	CS_MEM_EXCLUSIVE,
+	CS_MEM_HARDWALL,
+	CS_MEMORY_MIGRATE,
+	CS_SCHED_LOAD_BALANCE,
+	CS_SPREAD_PAGE,
+	CS_SPREAD_SLAB,
+} cpuset_flagbits_t;
+
+/* convenient tests for these bits */
+static inline int is_cpu_exclusive(const struct cpuset *cs)
+{
+	return test_bit(CS_CPU_EXCLUSIVE, &cs->flags);
+}
+
+static inline int is_mem_exclusive(const struct cpuset *cs)
+{
+	return test_bit(CS_MEM_EXCLUSIVE, &cs->flags);
+}
+
+static inline int is_mem_hardwall(const struct cpuset *cs)
+{
+	return test_bit(CS_MEM_HARDWALL, &cs->flags);
+}
+
+static inline int is_sched_load_balance(const struct cpuset *cs)
+{
+	return test_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
+}
+
+static inline int is_memory_migrate(const struct cpuset *cs)
+{
+	return test_bit(CS_MEMORY_MIGRATE, &cs->flags);
+}
+
+static inline int is_spread_page(const struct cpuset *cs)
+{
+	return test_bit(CS_SPREAD_PAGE, &cs->flags);
+}
+
+static inline int is_spread_slab(const struct cpuset *cs)
+{
+	return test_bit(CS_SPREAD_SLAB, &cs->flags);
+}
+
+static struct cpuset top_cpuset = {
+	.flags = ((1 << CS_CPU_EXCLUSIVE) | (1 << CS_MEM_EXCLUSIVE)),
+};
+
+/*
+ * There are two global mutexes guarding cpuset structures.  The first
+ * is the main control groups cgroup_mutex, accessed via
+ * cgroup_lock()/cgroup_unlock().  The second is the cpuset-specific
+ * callback_mutex, below. They can nest.  It is ok to first take
+ * cgroup_mutex, then nest callback_mutex.  We also require taking
+ * task_lock() when dereferencing a task's cpuset pointer.  See "The
+ * task_lock() exception", at the end of this comment.
+ *
+ * A task must hold both mutexes to modify cpusets.  If a task
+ * holds cgroup_mutex, then it blocks others wanting that mutex,
+ * ensuring that it is the only task able to also acquire callback_mutex
+ * and be able to modify cpusets.  It can perform various checks on
+ * the cpuset structure first, knowing nothing will change.  It can
+ * also allocate memory while just holding cgroup_mutex.  While it is
+ * performing these checks, various callback routines can briefly
+ * acquire callback_mutex to query cpusets.  Once it is ready to make
+ * the changes, it takes callback_mutex, blocking everyone else.
+ *
+ * Calls to the kernel memory allocator can not be made while holding
+ * callback_mutex, as that would risk double tripping on callback_mutex
+ * from one of the callbacks into the cpuset code from within
+ * __alloc_pages().
+ *
+ * If a task is only holding callback_mutex, then it has read-only
+ * access to cpusets.
+ *
+ * Now, the task_struct fields mems_allowed and mempolicy may be changed
+ * by other task, we use alloc_lock in the task_struct fields to protect
+ * them.
+ *
+ * The cpuset_common_file_read() handlers only hold callback_mutex across
+ * small pieces of code, such as when reading out possibly multi-word
+ * cpumasks and nodemasks.
+ *
+ * Accessing a task's cpuset should be done in accordance with the
+ * guidelines for accessing subsystem state in kernel/cgroup.c
+ */
+
+static DEFINE_MUTEX(callback_mutex);
+
+/*
+ * cpuset_buffer_lock protects both the cpuset_name and cpuset_nodelist
+ * buffers.  They are statically allocated to prevent using excess stack
+ * when calling cpuset_print_task_mems_allowed().
+ */
+#define CPUSET_NAME_LEN		(128)
+#define	CPUSET_NODELIST_LEN	(256)
+static char cpuset_name[CPUSET_NAME_LEN];
+static char cpuset_nodelist[CPUSET_NODELIST_LEN];
+static DEFINE_SPINLOCK(cpuset_buffer_lock);
+
+/*
+ * This is ugly, but preserves the userspace API for existing cpuset
+ * users. If someone tries to mount the "cpuset" filesystem, we
+ * silently switch it to mount "cgroup" instead
+ */
+static struct dentry *cpuset_mount(struct file_system_type *fs_type,
+			 int flags, const char *unused_dev_name, void *data)
+{
+	struct file_system_type *cgroup_fs = get_fs_type("cgroup");
+	struct dentry *ret = ERR_PTR(-ENODEV);
+	if (cgroup_fs) {
+		char mountopts[] =
+			"cpuset,noprefix,"
+			"release_agent=/sbin/cpuset_release_agent";
+		ret = cgroup_fs->mount(cgroup_fs, flags,
+					   unused_dev_name, mountopts);
+		put_filesystem(cgroup_fs);
+	}
+	return ret;
+}
+
+static struct file_system_type cpuset_fs_type = {
+	.name = "cpuset",
+	.mount = cpuset_mount,
+};
+
+/*
+ * Return in pmask the portion of a cpusets's cpus_allowed that
+ * are online.  If none are online, walk up the cpuset hierarchy
+ * until we find one that does have some online cpus.  If we get
+ * all the way to the top and still haven't found any online cpus,
+ * return cpu_online_map.  Or if passed a NULL cs from an exit'ing
+ * task, return cpu_online_map.
+ *
+ * One way or another, we guarantee to return some non-empty subset
+ * of cpu_online_map.
+ *
+ * Call with callback_mutex held.
+ */
+
+static void guarantee_online_cpus(const struct cpuset *cs,
+				  struct cpumask *pmask)
+{
+	while (cs && !cpumask_intersects(cs->cpus_allowed, cpu_online_mask))
+		cs = cs->parent;
+	if (cs)
+		cpumask_and(pmask, cs->cpus_allowed, cpu_online_mask);
+	else
+		cpumask_copy(pmask, cpu_online_mask);
+	BUG_ON(!cpumask_intersects(pmask, cpu_online_mask));
+}
+
+/*
+ * Return in *pmask the portion of a cpusets's mems_allowed that
+ * are online, with memory.  If none are online with memory, walk
+ * up the cpuset hierarchy until we find one that does have some
+ * online mems.  If we get all the way to the top and still haven't
+ * found any online mems, return node_states[N_HIGH_MEMORY].
+ *
+ * One way or another, we guarantee to return some non-empty subset
+ * of node_states[N_HIGH_MEMORY].
+ *
+ * Call with callback_mutex held.
+ */
+
+static void guarantee_online_mems(const struct cpuset *cs, nodemask_t *pmask)
+{
+	while (cs && !nodes_intersects(cs->mems_allowed,
+					node_states[N_HIGH_MEMORY]))
+		cs = cs->parent;
+	if (cs)
+		nodes_and(*pmask, cs->mems_allowed,
+					node_states[N_HIGH_MEMORY]);
+	else
+		*pmask = node_states[N_HIGH_MEMORY];
+	BUG_ON(!nodes_intersects(*pmask, node_states[N_HIGH_MEMORY]));
+}
+
+/*
+ * update task's spread flag if cpuset's page/slab spread flag is set
+ *
+ * Called with callback_mutex/cgroup_mutex held
+ */
+static void cpuset_update_task_spread_flag(struct cpuset *cs,
+					struct task_struct *tsk)
+{
+	if (is_spread_page(cs))
+		tsk->flags |= PF_SPREAD_PAGE;
+	else
+		tsk->flags &= ~PF_SPREAD_PAGE;
+	if (is_spread_slab(cs))
+		tsk->flags |= PF_SPREAD_SLAB;
+	else
+		tsk->flags &= ~PF_SPREAD_SLAB;
+}
+
+/*
+ * is_cpuset_subset(p, q) - Is cpuset p a subset of cpuset q?
+ *
+ * One cpuset is a subset of another if all its allowed CPUs and
+ * Memory Nodes are a subset of the other, and its exclusive flags
+ * are only set if the other's are set.  Call holding cgroup_mutex.
+ */
+
+static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q)
+{
+	return	cpumask_subset(p->cpus_allowed, q->cpus_allowed) &&
+		nodes_subset(p->mems_allowed, q->mems_allowed) &&
+		is_cpu_exclusive(p) <= is_cpu_exclusive(q) &&
+		is_mem_exclusive(p) <= is_mem_exclusive(q);
+}
+
+/**
+ * alloc_trial_cpuset - allocate a trial cpuset
+ * @cs: the cpuset that the trial cpuset duplicates
+ */
+static struct cpuset *alloc_trial_cpuset(const struct cpuset *cs)
+{
+	struct cpuset *trial;
+
+	trial = kmemdup(cs, sizeof(*cs), GFP_KERNEL);
+	if (!trial)
+		return NULL;
+
+	if (!alloc_cpumask_var(&trial->cpus_allowed, GFP_KERNEL)) {
+		kfree(trial);
+		return NULL;
+	}
+	cpumask_copy(trial->cpus_allowed, cs->cpus_allowed);
+
+	return trial;
+}
+
+/**
+ * free_trial_cpuset - free the trial cpuset
+ * @trial: the trial cpuset to be freed
+ */
+static void free_trial_cpuset(struct cpuset *trial)
+{
+	free_cpumask_var(trial->cpus_allowed);
+	kfree(trial);
+}
+
+/*
+ * validate_change() - Used to validate that any proposed cpuset change
+ *		       follows the structural rules for cpusets.
+ *
+ * If we replaced the flag and mask values of the current cpuset
+ * (cur) with those values in the trial cpuset (trial), would
+ * our various subset and exclusive rules still be valid?  Presumes
+ * cgroup_mutex held.
+ *
+ * 'cur' is the address of an actual, in-use cpuset.  Operations
+ * such as list traversal that depend on the actual address of the
+ * cpuset in the list must use cur below, not trial.
+ *
+ * 'trial' is the address of bulk structure copy of cur, with
+ * perhaps one or more of the fields cpus_allowed, mems_allowed,
+ * or flags changed to new, trial values.
+ *
+ * Return 0 if valid, -errno if not.
+ */
+
+static int validate_change(const struct cpuset *cur, const struct cpuset *trial)
+{
+	struct cgroup *cont;
+	struct cpuset *c, *par;
+
+	/* Each of our child cpusets must be a subset of us */
+	list_for_each_entry(cont, &cur->css.cgroup->children, sibling) {
+		if (!is_cpuset_subset(cgroup_cs(cont), trial))
+			return -EBUSY;
+	}
+
+	/* Remaining checks don't apply to root cpuset */
+	if (cur == &top_cpuset)
+		return 0;
+
+	par = cur->parent;
+
+	/* We must be a subset of our parent cpuset */
+	if (!is_cpuset_subset(trial, par))
+		return -EACCES;
+
+	/*
+	 * If either I or some sibling (!= me) is exclusive, we can't
+	 * overlap
+	 */
+	list_for_each_entry(cont, &par->css.cgroup->children, sibling) {
+		c = cgroup_cs(cont);
+		if ((is_cpu_exclusive(trial) || is_cpu_exclusive(c)) &&
+		    c != cur &&
+		    cpumask_intersects(trial->cpus_allowed, c->cpus_allowed))
+			return -EINVAL;
+		if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) &&
+		    c != cur &&
+		    nodes_intersects(trial->mems_allowed, c->mems_allowed))
+			return -EINVAL;
+	}
+
+	/* Cpusets with tasks can't have empty cpus_allowed or mems_allowed */
+	if (cgroup_task_count(cur->css.cgroup)) {
+		if (cpumask_empty(trial->cpus_allowed) ||
+		    nodes_empty(trial->mems_allowed)) {
+			return -ENOSPC;
+		}
+	}
+
+	return 0;
+}
+
+#ifdef CONFIG_SMP
+/*
+ * Helper routine for generate_sched_domains().
+ * Do cpusets a, b have overlapping cpus_allowed masks?
+ */
+static int cpusets_overlap(struct cpuset *a, struct cpuset *b)
+{
+	return cpumask_intersects(a->cpus_allowed, b->cpus_allowed);
+}
+
+static void
+update_domain_attr(struct sched_domain_attr *dattr, struct cpuset *c)
+{
+	if (dattr->relax_domain_level < c->relax_domain_level)
+		dattr->relax_domain_level = c->relax_domain_level;
+	return;
+}
+
+static void
+update_domain_attr_tree(struct sched_domain_attr *dattr, struct cpuset *c)
+{
+	LIST_HEAD(q);
+
+	list_add(&c->stack_list, &q);
+	while (!list_empty(&q)) {
+		struct cpuset *cp;
+		struct cgroup *cont;
+		struct cpuset *child;
+
+		cp = list_first_entry(&q, struct cpuset, stack_list);
+		list_del(q.next);
+
+		if (cpumask_empty(cp->cpus_allowed))
+			continue;
+
+		if (is_sched_load_balance(cp))
+			update_domain_attr(dattr, cp);
+
+		list_for_each_entry(cont, &cp->css.cgroup->children, sibling) {
+			child = cgroup_cs(cont);
+			list_add_tail(&child->stack_list, &q);
+		}
+	}
+}
+
+/*
+ * generate_sched_domains()
+ *
+ * This function builds a partial partition of the systems CPUs
+ * A 'partial partition' is a set of non-overlapping subsets whose
+ * union is a subset of that set.
+ * The output of this function needs to be passed to kernel/sched.c
+ * partition_sched_domains() routine, which will rebuild the scheduler's
+ * load balancing domains (sched domains) as specified by that partial
+ * partition.
+ *
+ * See "What is sched_load_balance" in Documentation/cgroups/cpusets.txt
+ * for a background explanation of this.
+ *
+ * Does not return errors, on the theory that the callers of this
+ * routine would rather not worry about failures to rebuild sched
+ * domains when operating in the severe memory shortage situations
+ * that could cause allocation failures below.
+ *
+ * Must be called with cgroup_lock held.
+ *
+ * The three key local variables below are:
+ *    q  - a linked-list queue of cpuset pointers, used to implement a
+ *	   top-down scan of all cpusets.  This scan loads a pointer
+ *	   to each cpuset marked is_sched_load_balance into the
+ *	   array 'csa'.  For our purposes, rebuilding the schedulers
+ *	   sched domains, we can ignore !is_sched_load_balance cpusets.
+ *  csa  - (for CpuSet Array) Array of pointers to all the cpusets
+ *	   that need to be load balanced, for convenient iterative
+ *	   access by the subsequent code that finds the best partition,
+ *	   i.e the set of domains (subsets) of CPUs such that the
+ *	   cpus_allowed of every cpuset marked is_sched_load_balance
+ *	   is a subset of one of these domains, while there are as
+ *	   many such domains as possible, each as small as possible.
+ * doms  - Conversion of 'csa' to an array of cpumasks, for passing to
+ *	   the kernel/sched.c routine partition_sched_domains() in a
+ *	   convenient format, that can be easily compared to the prior
+ *	   value to determine what partition elements (sched domains)
+ *	   were changed (added or removed.)
+ *
+ * Finding the best partition (set of domains):
+ *	The triple nested loops below over i, j, k scan over the
+ *	load balanced cpusets (using the array of cpuset pointers in
+ *	csa[]) looking for pairs of cpusets that have overlapping
+ *	cpus_allowed, but which don't have the same 'pn' partition
+ *	number and gives them in the same partition number.  It keeps
+ *	looping on the 'restart' label until it can no longer find
+ *	any such pairs.
+ *
+ *	The union of the cpus_allowed masks from the set of
+ *	all cpusets having the same 'pn' value then form the one
+ *	element of the partition (one sched domain) to be passed to
+ *	partition_sched_domains().
+ */
+static int generate_sched_domains(cpumask_var_t **domains,
+			struct sched_domain_attr **attributes)
+{
+	LIST_HEAD(q);		/* queue of cpusets to be scanned */
+	struct cpuset *cp;	/* scans q */
+	struct cpuset **csa;	/* array of all cpuset ptrs */
+	int csn;		/* how many cpuset ptrs in csa so far */
+	int i, j, k;		/* indices for partition finding loops */
+	cpumask_var_t *doms;	/* resulting partition; i.e. sched domains */
+	struct sched_domain_attr *dattr;  /* attributes for custom domains */
+	int ndoms = 0;		/* number of sched domains in result */
+	int nslot;		/* next empty doms[] struct cpumask slot */
+
+	doms = NULL;
+	dattr = NULL;
+	csa = NULL;
+
+	/* Special case for the 99% of systems with one, full, sched domain */
+	if (is_sched_load_balance(&top_cpuset)) {
+		ndoms = 1;
+		doms = alloc_sched_domains(ndoms);
+		if (!doms)
+			goto done;
+
+		dattr = kmalloc(sizeof(struct sched_domain_attr), GFP_KERNEL);
+		if (dattr) {
+			*dattr = SD_ATTR_INIT;
+			update_domain_attr_tree(dattr, &top_cpuset);
+		}
+		cpumask_copy(doms[0], top_cpuset.cpus_allowed);
+
+		goto done;
+	}
+
+	csa = kmalloc(number_of_cpusets * sizeof(cp), GFP_KERNEL);
+	if (!csa)
+		goto done;
+	csn = 0;
+
+	list_add(&top_cpuset.stack_list, &q);
+	while (!list_empty(&q)) {
+		struct cgroup *cont;
+		struct cpuset *child;   /* scans child cpusets of cp */
+
+		cp = list_first_entry(&q, struct cpuset, stack_list);
+		list_del(q.next);
+
+		if (cpumask_empty(cp->cpus_allowed))
+			continue;
+
+		/*
+		 * All child cpusets contain a subset of the parent's cpus, so
+		 * just skip them, and then we call update_domain_attr_tree()
+		 * to calc relax_domain_level of the corresponding sched
+		 * domain.
+		 */
+		if (is_sched_load_balance(cp)) {
+			csa[csn++] = cp;
+			continue;
+		}
+
+		list_for_each_entry(cont, &cp->css.cgroup->children, sibling) {
+			child = cgroup_cs(cont);
+			list_add_tail(&child->stack_list, &q);
+		}
+  	}
+
+	for (i = 0; i < csn; i++)
+		csa[i]->pn = i;
+	ndoms = csn;
+
+restart:
+	/* Find the best partition (set of sched domains) */
+	for (i = 0; i < csn; i++) {
+		struct cpuset *a = csa[i];
+		int apn = a->pn;
+
+		for (j = 0; j < csn; j++) {
+			struct cpuset *b = csa[j];
+			int bpn = b->pn;
+
+			if (apn != bpn && cpusets_overlap(a, b)) {
+				for (k = 0; k < csn; k++) {
+					struct cpuset *c = csa[k];
+
+					if (c->pn == bpn)
+						c->pn = apn;
+				}
+				ndoms--;	/* one less element */
+				goto restart;
+			}
+		}
+	}
+
+	/*
+	 * Now we know how many domains to create.
+	 * Convert <csn, csa> to <ndoms, doms> and populate cpu masks.
+	 */
+	doms = alloc_sched_domains(ndoms);
+	if (!doms)
+		goto done;
+
+	/*
+	 * The rest of the code, including the scheduler, can deal with
+	 * dattr==NULL case. No need to abort if alloc fails.
+	 */
+	dattr = kmalloc(ndoms * sizeof(struct sched_domain_attr), GFP_KERNEL);
+
+	for (nslot = 0, i = 0; i < csn; i++) {
+		struct cpuset *a = csa[i];
+		struct cpumask *dp;
+		int apn = a->pn;
+
+		if (apn < 0) {
+			/* Skip completed partitions */
+			continue;
+		}
+
+		dp = doms[nslot];
+
+		if (nslot == ndoms) {
+			static int warnings = 10;
+			if (warnings) {
+				printk(KERN_WARNING
+				 "rebuild_sched_domains confused:"
+				  " nslot %d, ndoms %d, csn %d, i %d,"
+				  " apn %d\n",
+				  nslot, ndoms, csn, i, apn);
+				warnings--;
+			}
+			continue;
+		}
+
+		cpumask_clear(dp);
+		if (dattr)
+			*(dattr + nslot) = SD_ATTR_INIT;
+		for (j = i; j < csn; j++) {
+			struct cpuset *b = csa[j];
+
+			if (apn == b->pn) {
+				cpumask_or(dp, dp, b->cpus_allowed);
+				if (dattr)
+					update_domain_attr_tree(dattr + nslot, b);
+
+				/* Done with this partition */
+				b->pn = -1;
+			}
+		}
+		nslot++;
+	}
+	BUG_ON(nslot != ndoms);
+
+done:
+	kfree(csa);
+
+	/*
+	 * Fallback to the default domain if kmalloc() failed.
+	 * See comments in partition_sched_domains().
+	 */
+	if (doms == NULL)
+		ndoms = 1;
+
+	*domains    = doms;
+	*attributes = dattr;
+	return ndoms;
+}
+
+/*
+ * Rebuild scheduler domains.
+ *
+ * Call with neither cgroup_mutex held nor within get_online_cpus().
+ * Takes both cgroup_mutex and get_online_cpus().
+ *
+ * Cannot be directly called from cpuset code handling changes
+ * to the cpuset pseudo-filesystem, because it cannot be called
+ * from code that already holds cgroup_mutex.
+ */
+static void do_rebuild_sched_domains(struct work_struct *unused)
+{
+	struct sched_domain_attr *attr;
+	cpumask_var_t *doms;
+	int ndoms;
+
+	get_online_cpus();
+
+	/* Generate domain masks and attrs */
+	cgroup_lock();
+	ndoms = generate_sched_domains(&doms, &attr);
+	cgroup_unlock();
+
+	/* Have scheduler rebuild the domains */
+	partition_sched_domains(ndoms, doms, attr);
+
+	put_online_cpus();
+}
+#else /* !CONFIG_SMP */
+static void do_rebuild_sched_domains(struct work_struct *unused)
+{
+}
+
+static int generate_sched_domains(cpumask_var_t **domains,
+			struct sched_domain_attr **attributes)
+{
+	*domains = NULL;
+	return 1;
+}
+#endif /* CONFIG_SMP */
+
+static DECLARE_WORK(rebuild_sched_domains_work, do_rebuild_sched_domains);
+
+/*
+ * Rebuild scheduler domains, asynchronously via workqueue.
+ *
+ * If the flag 'sched_load_balance' of any cpuset with non-empty
+ * 'cpus' changes, or if the 'cpus' allowed changes in any cpuset
+ * which has that flag enabled, or if any cpuset with a non-empty
+ * 'cpus' is removed, then call this routine to rebuild the
+ * scheduler's dynamic sched domains.
+ *
+ * The rebuild_sched_domains() and partition_sched_domains()
+ * routines must nest cgroup_lock() inside get_online_cpus(),
+ * but such cpuset changes as these must nest that locking the
+ * other way, holding cgroup_lock() for much of the code.
+ *
+ * So in order to avoid an ABBA deadlock, the cpuset code handling
+ * these user changes delegates the actual sched domain rebuilding
+ * to a separate workqueue thread, which ends up processing the
+ * above do_rebuild_sched_domains() function.
+ */
+static void async_rebuild_sched_domains(void)
+{
+	queue_work(cpuset_wq, &rebuild_sched_domains_work);
+}
+
+/*
+ * Accomplishes the same scheduler domain rebuild as the above
+ * async_rebuild_sched_domains(), however it directly calls the
+ * rebuild routine synchronously rather than calling it via an
+ * asynchronous work thread.
+ *
+ * This can only be called from code that is not holding
+ * cgroup_mutex (not nested in a cgroup_lock() call.)
+ */
+void rebuild_sched_domains(void)
+{
+	do_rebuild_sched_domains(NULL);
+}
+
+/**
+ * cpuset_test_cpumask - test a task's cpus_allowed versus its cpuset's
+ * @tsk: task to test
+ * @scan: struct cgroup_scanner contained in its struct cpuset_hotplug_scanner
+ *
+ * Call with cgroup_mutex held.  May take callback_mutex during call.
+ * Called for each task in a cgroup by cgroup_scan_tasks().
+ * Return nonzero if this tasks's cpus_allowed mask should be changed (in other
+ * words, if its mask is not equal to its cpuset's mask).
+ */
+static int cpuset_test_cpumask(struct task_struct *tsk,
+			       struct cgroup_scanner *scan)
+{
+	return !cpumask_equal(&tsk->cpus_allowed,
+			(cgroup_cs(scan->cg))->cpus_allowed);
+}
+
+/**
+ * cpuset_change_cpumask - make a task's cpus_allowed the same as its cpuset's
+ * @tsk: task to test
+ * @scan: struct cgroup_scanner containing the cgroup of the task
+ *
+ * Called by cgroup_scan_tasks() for each task in a cgroup whose
+ * cpus_allowed mask needs to be changed.
+ *
+ * We don't need to re-check for the cgroup/cpuset membership, since we're
+ * holding cgroup_lock() at this point.
+ */
+static void cpuset_change_cpumask(struct task_struct *tsk,
+				  struct cgroup_scanner *scan)
+{
+	set_cpus_allowed_ptr(tsk, ((cgroup_cs(scan->cg))->cpus_allowed));
+}
+
+/**
+ * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset.
+ * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed
+ * @heap: if NULL, defer allocating heap memory to cgroup_scan_tasks()
+ *
+ * Called with cgroup_mutex held
+ *
+ * The cgroup_scan_tasks() function will scan all the tasks in a cgroup,
+ * calling callback functions for each.
+ *
+ * No return value. It's guaranteed that cgroup_scan_tasks() always returns 0
+ * if @heap != NULL.
+ */
+static void update_tasks_cpumask(struct cpuset *cs, struct ptr_heap *heap)
+{
+	struct cgroup_scanner scan;
+
+	scan.cg = cs->css.cgroup;
+	scan.test_task = cpuset_test_cpumask;
+	scan.process_task = cpuset_change_cpumask;
+	scan.heap = heap;
+	cgroup_scan_tasks(&scan);
+}
+
+/**
+ * update_cpumask - update the cpus_allowed mask of a cpuset and all tasks in it
+ * @cs: the cpuset to consider
+ * @buf: buffer of cpu numbers written to this cpuset
+ */
+static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs,
+			  const char *buf)
+{
+	struct ptr_heap heap;
+	int retval;
+	int is_load_balanced;
+
+	/* top_cpuset.cpus_allowed tracks cpu_online_map; it's read-only */
+	if (cs == &top_cpuset)
+		return -EACCES;
+
+	/*
+	 * An empty cpus_allowed is ok only if the cpuset has no tasks.
+	 * Since cpulist_parse() fails on an empty mask, we special case
+	 * that parsing.  The validate_change() call ensures that cpusets
+	 * with tasks have cpus.
+	 */
+	if (!*buf) {
+		cpumask_clear(trialcs->cpus_allowed);
+	} else {
+		retval = cpulist_parse(buf, trialcs->cpus_allowed);
+		if (retval < 0)
+			return retval;
+
+		if (!cpumask_subset(trialcs->cpus_allowed, cpu_active_mask))
+			return -EINVAL;
+	}
+	retval = validate_change(cs, trialcs);
+	if (retval < 0)
+		return retval;
+
+	/* Nothing to do if the cpus didn't change */
+	if (cpumask_equal(cs->cpus_allowed, trialcs->cpus_allowed))
+		return 0;
+
+	retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL);
+	if (retval)
+		return retval;
+
+	is_load_balanced = is_sched_load_balance(trialcs);
+
+	mutex_lock(&callback_mutex);
+	cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed);
+	mutex_unlock(&callback_mutex);
+
+	/*
+	 * Scan tasks in the cpuset, and update the cpumasks of any
+	 * that need an update.
+	 */
+	update_tasks_cpumask(cs, &heap);
+
+	heap_free(&heap);
+
+	if (is_load_balanced)
+		async_rebuild_sched_domains();
+	return 0;
+}
+
+/*
+ * cpuset_migrate_mm
+ *
+ *    Migrate memory region from one set of nodes to another.
+ *
+ *    Temporarilly set tasks mems_allowed to target nodes of migration,
+ *    so that the migration code can allocate pages on these nodes.
+ *
+ *    Call holding cgroup_mutex, so current's cpuset won't change
+ *    during this call, as manage_mutex holds off any cpuset_attach()
+ *    calls.  Therefore we don't need to take task_lock around the
+ *    call to guarantee_online_mems(), as we know no one is changing
+ *    our task's cpuset.
+ *
+ *    While the mm_struct we are migrating is typically from some
+ *    other task, the task_struct mems_allowed that we are hacking
+ *    is for our current task, which must allocate new pages for that
+ *    migrating memory region.
+ */
+
+static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from,
+							const nodemask_t *to)
+{
+	struct task_struct *tsk = current;
+
+	tsk->mems_allowed = *to;
+
+	do_migrate_pages(mm, from, to, MPOL_MF_MOVE_ALL);
+
+	guarantee_online_mems(task_cs(tsk),&tsk->mems_allowed);
+}
+
+/*
+ * cpuset_change_task_nodemask - change task's mems_allowed and mempolicy
+ * @tsk: the task to change
+ * @newmems: new nodes that the task will be set
+ *
+ * In order to avoid seeing no nodes if the old and new nodes are disjoint,
+ * we structure updates as setting all new allowed nodes, then clearing newly
+ * disallowed ones.
+ */
+static void cpuset_change_task_nodemask(struct task_struct *tsk,
+					nodemask_t *newmems)
+{
+	bool need_loop;
+
+repeat:
+	/*
+	 * Allow tasks that have access to memory reserves because they have
+	 * been OOM killed to get memory anywhere.
+	 */
+	if (unlikely(test_thread_flag(TIF_MEMDIE)))
+		return;
+	if (current->flags & PF_EXITING) /* Let dying task have memory */
+		return;
+
+	task_lock(tsk);
+	/*
+	 * Determine if a loop is necessary if another thread is doing
+	 * get_mems_allowed().  If at least one node remains unchanged and
+	 * tsk does not have a mempolicy, then an empty nodemask will not be
+	 * possible when mems_allowed is larger than a word.
+	 */
+	need_loop = task_has_mempolicy(tsk) ||
+			!nodes_intersects(*newmems, tsk->mems_allowed);
+	nodes_or(tsk->mems_allowed, tsk->mems_allowed, *newmems);
+	mpol_rebind_task(tsk, newmems, MPOL_REBIND_STEP1);
+
+	/*
+	 * ensure checking ->mems_allowed_change_disable after setting all new
+	 * allowed nodes.
+	 *
+	 *