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authorAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
committerAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
commitb4b6116a13633898cf868f2f103c96a90c4c20f8 (patch)
tree93d1b7e2cfcdf473d8d4ff3ad141fa864f8491f6 /arch/s390/kernel/entry.S
parentedd4be777c953e5faafc80d091d3084b4343f5d3 (diff)
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fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'arch/s390/kernel/entry.S')
-rw-r--r--arch/s390/kernel/entry.S950
1 files changed, 950 insertions, 0 deletions
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
new file mode 100644
index 00000000000..3705700ed37
--- /dev/null
+++ b/arch/s390/kernel/entry.S
@@ -0,0 +1,950 @@
+/*
+ * arch/s390/kernel/entry.S
+ * S390 low-level entry points.
+ *
+ * Copyright (C) IBM Corp. 1999,2006
+ * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
+ * Hartmut Penner (hp@de.ibm.com),
+ * Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
+ * Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <asm/cache.h>
+#include <asm/errno.h>
+#include <asm/ptrace.h>
+#include <asm/thread_info.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+#include <asm/page.h>
+
+__PT_R0 = __PT_GPRS
+__PT_R1 = __PT_GPRS + 4
+__PT_R2 = __PT_GPRS + 8
+__PT_R3 = __PT_GPRS + 12
+__PT_R4 = __PT_GPRS + 16
+__PT_R5 = __PT_GPRS + 20
+__PT_R6 = __PT_GPRS + 24
+__PT_R7 = __PT_GPRS + 28
+__PT_R8 = __PT_GPRS + 32
+__PT_R9 = __PT_GPRS + 36
+__PT_R10 = __PT_GPRS + 40
+__PT_R11 = __PT_GPRS + 44
+__PT_R12 = __PT_GPRS + 48
+__PT_R13 = __PT_GPRS + 524
+__PT_R14 = __PT_GPRS + 56
+__PT_R15 = __PT_GPRS + 60
+
+_TIF_WORK_SVC = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
+ _TIF_MCCK_PENDING | _TIF_PER_TRAP )
+_TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | \
+ _TIF_MCCK_PENDING)
+_TIF_TRACE = (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | _TIF_SECCOMP | \
+ _TIF_SYSCALL_TRACEPOINT)
+
+STACK_SHIFT = PAGE_SHIFT + THREAD_ORDER
+STACK_SIZE = 1 << STACK_SHIFT
+
+#define BASED(name) name-system_call(%r13)
+
+ .macro TRACE_IRQS_ON
+#ifdef CONFIG_TRACE_IRQFLAGS
+ basr %r2,%r0
+ l %r1,BASED(.Lhardirqs_on)
+ basr %r14,%r1 # call trace_hardirqs_on_caller
+#endif
+ .endm
+
+ .macro TRACE_IRQS_OFF
+#ifdef CONFIG_TRACE_IRQFLAGS
+ basr %r2,%r0
+ l %r1,BASED(.Lhardirqs_off)
+ basr %r14,%r1 # call trace_hardirqs_off_caller
+#endif
+ .endm
+
+ .macro LOCKDEP_SYS_EXIT
+#ifdef CONFIG_LOCKDEP
+ tm __PT_PSW+1(%r11),0x01 # returning to user ?
+ jz .+10
+ l %r1,BASED(.Llockdep_sys_exit)
+ basr %r14,%r1 # call lockdep_sys_exit
+#endif
+ .endm
+
+ .macro CHECK_STACK stacksize,savearea
+#ifdef CONFIG_CHECK_STACK
+ tml %r15,\stacksize - CONFIG_STACK_GUARD
+ la %r14,\savearea
+ jz stack_overflow
+#endif
+ .endm
+
+ .macro SWITCH_ASYNC savearea,stack,shift
+ tmh %r8,0x0001 # interrupting from user ?
+ jnz 1f
+ lr %r14,%r9
+ sl %r14,BASED(.Lcritical_start)
+ cl %r14,BASED(.Lcritical_length)
+ jhe 0f
+ la %r11,\savearea # inside critical section, do cleanup
+ bras %r14,cleanup_critical
+ tmh %r8,0x0001 # retest problem state after cleanup
+ jnz 1f
+0: l %r14,\stack # are we already on the target stack?
+ slr %r14,%r15
+ sra %r14,\shift
+ jnz 1f
+ CHECK_STACK 1<<\shift,\savearea
+ j 2f
+1: l %r15,\stack # load target stack
+2: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ la %r11,STACK_FRAME_OVERHEAD(%r15)
+ .endm
+
+ .macro ADD64 high,low,timer
+ al \high,\timer
+ al \low,\timer+4
+ brc 12,.+8
+ ahi \high,1
+ .endm
+
+ .macro SUB64 high,low,timer
+ sl \high,\timer
+ sl \low,\timer+4
+ brc 3,.+8
+ ahi \high,-1
+ .endm
+
+ .macro UPDATE_VTIME high,low,enter_timer
+ lm \high,\low,__LC_EXIT_TIMER
+ SUB64 \high,\low,\enter_timer
+ ADD64 \high,\low,__LC_USER_TIMER
+ stm \high,\low,__LC_USER_TIMER
+ lm \high,\low,__LC_LAST_UPDATE_TIMER
+ SUB64 \high,\low,__LC_EXIT_TIMER
+ ADD64 \high,\low,__LC_SYSTEM_TIMER
+ stm \high,\low,__LC_SYSTEM_TIMER
+ mvc __LC_LAST_UPDATE_TIMER(8),\enter_timer
+ .endm
+
+ .macro REENABLE_IRQS
+ st %r8,__LC_RETURN_PSW
+ ni __LC_RETURN_PSW,0xbf
+ ssm __LC_RETURN_PSW
+ .endm
+
+ .section .kprobes.text, "ax"
+
+/*
+ * Scheduler resume function, called by switch_to
+ * gpr2 = (task_struct *) prev
+ * gpr3 = (task_struct *) next
+ * Returns:
+ * gpr2 = prev
+ */
+ENTRY(__switch_to)
+ l %r4,__THREAD_info(%r2) # get thread_info of prev
+ l %r5,__THREAD_info(%r3) # get thread_info of next
+ tm __TI_flags+3(%r4),_TIF_MCCK_PENDING # machine check pending?
+ jz 0f
+ ni __TI_flags+3(%r4),255-_TIF_MCCK_PENDING # clear flag in prev
+ oi __TI_flags+3(%r5),_TIF_MCCK_PENDING # set it in next
+0: stm %r6,%r15,__SF_GPRS(%r15) # store gprs of prev task
+ st %r15,__THREAD_ksp(%r2) # store kernel stack of prev
+ l %r15,__THREAD_ksp(%r3) # load kernel stack of next
+ lctl %c4,%c4,__TASK_pid(%r3) # load pid to control reg. 4
+ lm %r6,%r15,__SF_GPRS(%r15) # load gprs of next task
+ st %r3,__LC_CURRENT # store task struct of next
+ mvc __LC_CURRENT_PID(4,%r0),__TASK_pid(%r3) # store pid of next
+ st %r5,__LC_THREAD_INFO # store thread info of next
+ ahi %r5,STACK_SIZE # end of kernel stack of next
+ st %r5,__LC_KERNEL_STACK # store end of kernel stack
+ br %r14
+
+__critical_start:
+/*
+ * SVC interrupt handler routine. System calls are synchronous events and
+ * are executed with interrupts enabled.
+ */
+
+ENTRY(system_call)
+ stpt __LC_SYNC_ENTER_TIMER
+sysc_stm:
+ stm %r8,%r15,__LC_SAVE_AREA_SYNC
+ l %r12,__LC_THREAD_INFO
+ l %r13,__LC_SVC_NEW_PSW+4
+sysc_per:
+ l %r15,__LC_KERNEL_STACK
+ ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ la %r11,STACK_FRAME_OVERHEAD(%r15) # pointer to pt_regs
+sysc_vtime:
+ UPDATE_VTIME %r8,%r9,__LC_SYNC_ENTER_TIMER
+ stm %r0,%r7,__PT_R0(%r11)
+ mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
+ mvc __PT_PSW(8,%r11),__LC_SVC_OLD_PSW
+ mvc __PT_INT_CODE(4,%r11),__LC_SVC_ILC
+sysc_do_svc:
+ oi __TI_flags+3(%r12),_TIF_SYSCALL
+ lh %r8,__PT_INT_CODE+2(%r11)
+ sla %r8,2 # shift and test for svc0
+ jnz sysc_nr_ok
+ # svc 0: system call number in %r1
+ cl %r1,BASED(.Lnr_syscalls)
+ jnl sysc_nr_ok
+ sth %r1,__PT_INT_CODE+2(%r11)
+ lr %r8,%r1
+ sla %r8,2
+sysc_nr_ok:
+ l %r10,BASED(.Lsys_call_table) # 31 bit system call table
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ st %r2,__PT_ORIG_GPR2(%r11)
+ st %r7,STACK_FRAME_OVERHEAD(%r15)
+ l %r9,0(%r8,%r10) # get system call addr.
+ tm __TI_flags+2(%r12),_TIF_TRACE >> 8
+ jnz sysc_tracesys
+ basr %r14,%r9 # call sys_xxxx
+ st %r2,__PT_R2(%r11) # store return value
+
+sysc_return:
+ LOCKDEP_SYS_EXIT
+sysc_tif:
+ tm __PT_PSW+1(%r11),0x01 # returning to user ?
+ jno sysc_restore
+ tm __TI_flags+3(%r12),_TIF_WORK_SVC
+ jnz sysc_work # check for work
+ ni __TI_flags+3(%r12),255-_TIF_SYSCALL
+sysc_restore:
+ mvc __LC_RETURN_PSW(8),__PT_PSW(%r11)
+ stpt __LC_EXIT_TIMER
+ lm %r0,%r15,__PT_R0(%r11)
+ lpsw __LC_RETURN_PSW
+sysc_done:
+
+#
+# One of the work bits is on. Find out which one.
+#
+sysc_work:
+ tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
+ jo sysc_mcck_pending
+ tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
+ jo sysc_reschedule
+ tm __TI_flags+3(%r12),_TIF_SIGPENDING
+ jo sysc_sigpending
+ tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
+ jo sysc_notify_resume
+ tm __TI_flags+3(%r12),_TIF_PER_TRAP
+ jo sysc_singlestep
+ j sysc_return # beware of critical section cleanup
+
+#
+# _TIF_NEED_RESCHED is set, call schedule
+#
+sysc_reschedule:
+ l %r1,BASED(.Lschedule)
+ la %r14,BASED(sysc_return)
+ br %r1 # call schedule
+
+#
+# _TIF_MCCK_PENDING is set, call handler
+#
+sysc_mcck_pending:
+ l %r1,BASED(.Lhandle_mcck)
+ la %r14,BASED(sysc_return)
+ br %r1 # TIF bit will be cleared by handler
+
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+sysc_sigpending:
+ ni __TI_flags+3(%r12),255-_TIF_PER_TRAP # clear TIF_PER_TRAP
+ lr %r2,%r11 # pass pointer to pt_regs
+ l %r1,BASED(.Ldo_signal)
+ basr %r14,%r1 # call do_signal
+ tm __TI_flags+3(%r12),_TIF_SYSCALL
+ jno sysc_return
+ lm %r2,%r7,__PT_R2(%r11) # load svc arguments
+ xr %r8,%r8 # svc 0 returns -ENOSYS
+ clc __PT_INT_CODE+2(2,%r11),BASED(.Lnr_syscalls+2)
+ jnl sysc_nr_ok # invalid svc number -> do svc 0
+ lh %r8,__PT_INT_CODE+2(%r11) # load new svc number
+ sla %r8,2
+ j sysc_nr_ok # restart svc
+
+#
+# _TIF_NOTIFY_RESUME is set, call do_notify_resume
+#
+sysc_notify_resume:
+ lr %r2,%r11 # pass pointer to pt_regs
+ l %r1,BASED(.Ldo_notify_resume)
+ la %r14,BASED(sysc_return)
+ br %r1 # call do_notify_resume
+
+#
+# _TIF_PER_TRAP is set, call do_per_trap
+#
+sysc_singlestep:
+ ni __TI_flags+3(%r12),255-(_TIF_SYSCALL | _TIF_PER_TRAP)
+ lr %r2,%r11 # pass pointer to pt_regs
+ l %r1,BASED(.Ldo_per_trap)
+ la %r14,BASED(sysc_return)
+ br %r1 # call do_per_trap
+
+#
+# call tracehook_report_syscall_entry/tracehook_report_syscall_exit before
+# and after the system call
+#
+sysc_tracesys:
+ l %r1,BASED(.Ltrace_enter)
+ lr %r2,%r11 # pass pointer to pt_regs
+ la %r3,0
+ xr %r0,%r0
+ icm %r0,3,__PT_INT_CODE+2(%r11)
+ st %r0,__PT_R2(%r11)
+ basr %r14,%r1 # call do_syscall_trace_enter
+ cl %r2,BASED(.Lnr_syscalls)
+ jnl sysc_tracenogo
+ lr %r8,%r2
+ sll %r8,2
+ l %r9,0(%r8,%r10)
+sysc_tracego:
+ lm %r3,%r7,__PT_R3(%r11)
+ st %r7,STACK_FRAME_OVERHEAD(%r15)
+ l %r2,__PT_ORIG_GPR2(%r11)
+ basr %r14,%r9 # call sys_xxx
+ st %r2,__PT_R2(%r11) # store return value
+sysc_tracenogo:
+ tm __TI_flags+2(%r12),_TIF_TRACE >> 8
+ jz sysc_return
+ l %r1,BASED(.Ltrace_exit)
+ lr %r2,%r11 # pass pointer to pt_regs
+ la %r14,BASED(sysc_return)
+ br %r1 # call do_syscall_trace_exit
+
+#
+# a new process exits the kernel with ret_from_fork
+#
+ENTRY(ret_from_fork)
+ la %r11,STACK_FRAME_OVERHEAD(%r15)
+ l %r12,__LC_THREAD_INFO
+ l %r13,__LC_SVC_NEW_PSW+4
+ tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
+ jo 0f
+ st %r15,__PT_R15(%r11) # store stack pointer for new kthread
+0: l %r1,BASED(.Lschedule_tail)
+ basr %r14,%r1 # call schedule_tail
+ TRACE_IRQS_ON
+ ssm __LC_SVC_NEW_PSW # reenable interrupts
+ j sysc_tracenogo
+
+#
+# kernel_execve function needs to deal with pt_regs that is not
+# at the usual place
+#
+ENTRY(kernel_execve)
+ stm %r12,%r15,48(%r15)
+ lr %r14,%r15
+ l %r13,__LC_SVC_NEW_PSW+4
+ ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ st %r14,__SF_BACKCHAIN(%r15)
+ la %r12,STACK_FRAME_OVERHEAD(%r15)
+ xc 0(__PT_SIZE,%r12),0(%r12)
+ l %r1,BASED(.Ldo_execve)
+ lr %r5,%r12
+ basr %r14,%r1 # call do_execve
+ ltr %r2,%r2
+ je 0f
+ ahi %r15,(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ lm %r12,%r15,48(%r15)
+ br %r14
+ # execve succeeded.
+0: ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
+ l %r15,__LC_KERNEL_STACK # load ksp
+ ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ la %r11,STACK_FRAME_OVERHEAD(%r15)
+ mvc 0(__PT_SIZE,%r11),0(%r12) # copy pt_regs
+ l %r12,__LC_THREAD_INFO
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ ssm __LC_SVC_NEW_PSW # reenable interrupts
+ l %r1,BASED(.Lexecve_tail)
+ basr %r14,%r1 # call execve_tail
+ j sysc_return
+
+/*
+ * Program check handler routine
+ */
+
+ENTRY(pgm_check_handler)
+ stpt __LC_SYNC_ENTER_TIMER
+ stm %r8,%r15,__LC_SAVE_AREA_SYNC
+ l %r12,__LC_THREAD_INFO
+ l %r13,__LC_SVC_NEW_PSW+4
+ lm %r8,%r9,__LC_PGM_OLD_PSW
+ tmh %r8,0x0001 # test problem state bit
+ jnz 1f # -> fault in user space
+ tmh %r8,0x4000 # PER bit set in old PSW ?
+ jnz 0f # -> enabled, can't be a double fault
+ tm __LC_PGM_ILC+3,0x80 # check for per exception
+ jnz pgm_svcper # -> single stepped svc
+0: CHECK_STACK STACK_SIZE,__LC_SAVE_AREA_SYNC
+ j 2f
+1: UPDATE_VTIME %r14,%r15,__LC_SYNC_ENTER_TIMER
+ l %r15,__LC_KERNEL_STACK
+2: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ la %r11,STACK_FRAME_OVERHEAD(%r15)
+ stm %r0,%r7,__PT_R0(%r11)
+ mvc __PT_R8(32,%r11),__LC_SAVE_AREA_SYNC
+ stm %r8,%r9,__PT_PSW(%r11)
+ mvc __PT_INT_CODE(4,%r11),__LC_PGM_ILC
+ mvc __PT_INT_PARM_LONG(4,%r11),__LC_TRANS_EXC_CODE
+ tm __LC_PGM_ILC+3,0x80 # check for per exception
+ jz 0f
+ l %r1,__TI_task(%r12)
+ tmh %r8,0x0001 # kernel per event ?
+ jz pgm_kprobe
+ oi __TI_flags+3(%r12),_TIF_PER_TRAP
+ mvc __THREAD_per_address(4,%r1),__LC_PER_ADDRESS
+ mvc __THREAD_per_cause(2,%r1),__LC_PER_CAUSE
+ mvc __THREAD_per_paid(1,%r1),__LC_PER_PAID
+0: REENABLE_IRQS
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ l %r1,BASED(.Ljump_table)
+ la %r10,0x7f
+ n %r10,__PT_INT_CODE(%r11)
+ je sysc_return
+ sll %r10,2
+ l %r1,0(%r10,%r1) # load address of handler routine
+ lr %r2,%r11 # pass pointer to pt_regs
+ basr %r14,%r1 # branch to interrupt-handler
+ j sysc_return
+
+#
+# PER event in supervisor state, must be kprobes
+#
+pgm_kprobe:
+ REENABLE_IRQS
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ l %r1,BASED(.Ldo_per_trap)
+ lr %r2,%r11 # pass pointer to pt_regs
+ basr %r14,%r1 # call do_per_trap
+ j sysc_return
+
+#
+# single stepped system call
+#
+pgm_svcper:
+ oi __TI_flags+3(%r12),_TIF_PER_TRAP
+ mvc __LC_RETURN_PSW(4),__LC_SVC_NEW_PSW
+ mvc __LC_RETURN_PSW+4(4),BASED(.Lsysc_per)
+ lpsw __LC_RETURN_PSW # branch to sysc_per and enable irqs
+
+/*
+ * IO interrupt handler routine
+ */
+
+ENTRY(io_int_handler)
+ stck __LC_INT_CLOCK
+ stpt __LC_ASYNC_ENTER_TIMER
+ stm %r8,%r15,__LC_SAVE_AREA_ASYNC
+ l %r12,__LC_THREAD_INFO
+ l %r13,__LC_SVC_NEW_PSW+4
+ lm %r8,%r9,__LC_IO_OLD_PSW
+ tmh %r8,0x0001 # interrupting from user ?
+ jz io_skip
+ UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER
+io_skip:
+ SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
+ stm %r0,%r7,__PT_R0(%r11)
+ mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
+ stm %r8,%r9,__PT_PSW(%r11)
+ TRACE_IRQS_OFF
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ l %r1,BASED(.Ldo_IRQ)
+ lr %r2,%r11 # pass pointer to pt_regs
+ basr %r14,%r1 # call do_IRQ
+io_return:
+ LOCKDEP_SYS_EXIT
+ TRACE_IRQS_ON
+io_tif:
+ tm __TI_flags+3(%r12),_TIF_WORK_INT
+ jnz io_work # there is work to do (signals etc.)
+io_restore:
+ mvc __LC_RETURN_PSW(8),__PT_PSW(%r11)
+ ni __LC_RETURN_PSW+1,0xfd # clean wait state bit
+ stpt __LC_EXIT_TIMER
+ lm %r0,%r15,__PT_R0(%r11)
+ lpsw __LC_RETURN_PSW
+io_done:
+
+#
+# There is work todo, find out in which context we have been interrupted:
+# 1) if we return to user space we can do all _TIF_WORK_INT work
+# 2) if we return to kernel code and preemptive scheduling is enabled check
+# the preemption counter and if it is zero call preempt_schedule_irq
+# Before any work can be done, a switch to the kernel stack is required.
+#
+io_work:
+ tm __PT_PSW+1(%r11),0x01 # returning to user ?
+ jo io_work_user # yes -> do resched & signal
+#ifdef CONFIG_PREEMPT
+ # check for preemptive scheduling
+ icm %r0,15,__TI_precount(%r12)
+ jnz io_restore # preemption disabled
+ tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
+ jno io_restore
+ # switch to kernel stack
+ l %r1,__PT_R15(%r11)
+ ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
+ xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
+ la %r11,STACK_FRAME_OVERHEAD(%r1)
+ lr %r15,%r1
+ # TRACE_IRQS_ON already done at io_return, call
+ # TRACE_IRQS_OFF to keep things symmetrical
+ TRACE_IRQS_OFF
+ l %r1,BASED(.Lpreempt_irq)
+ basr %r14,%r1 # call preempt_schedule_irq
+ j io_return
+#else
+ j io_restore
+#endif
+
+#
+# Need to do work before returning to userspace, switch to kernel stack
+#
+io_work_user:
+ l %r1,__LC_KERNEL_STACK
+ ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
+ xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
+ la %r11,STACK_FRAME_OVERHEAD(%r1)
+ lr %r15,%r1
+
+#
+# One of the work bits is on. Find out which one.
+# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
+# and _TIF_MCCK_PENDING
+#
+io_work_tif:
+ tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
+ jo io_mcck_pending
+ tm __TI_flags+3(%r12),_TIF_NEED_RESCHED
+ jo io_reschedule
+ tm __TI_flags+3(%r12),_TIF_SIGPENDING
+ jo io_sigpending
+ tm __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
+ jo io_notify_resume
+ j io_return # beware of critical section cleanup
+
+#
+# _TIF_MCCK_PENDING is set, call handler
+#
+io_mcck_pending:
+ # TRACE_IRQS_ON already done at io_return
+ l %r1,BASED(.Lhandle_mcck)
+ basr %r14,%r1 # TIF bit will be cleared by handler
+ TRACE_IRQS_OFF
+ j io_return
+
+#
+# _TIF_NEED_RESCHED is set, call schedule
+#
+io_reschedule:
+ # TRACE_IRQS_ON already done at io_return
+ l %r1,BASED(.Lschedule)
+ ssm __LC_SVC_NEW_PSW # reenable interrupts
+ basr %r14,%r1 # call scheduler
+ ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
+ TRACE_IRQS_OFF
+ j io_return
+
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+io_sigpending:
+ # TRACE_IRQS_ON already done at io_return
+ l %r1,BASED(.Ldo_signal)
+ ssm __LC_SVC_NEW_PSW # reenable interrupts
+ lr %r2,%r11 # pass pointer to pt_regs
+ basr %r14,%r1 # call do_signal
+ ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
+ TRACE_IRQS_OFF
+ j io_return
+
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+io_notify_resume:
+ # TRACE_IRQS_ON already done at io_return
+ l %r1,BASED(.Ldo_notify_resume)
+ ssm __LC_SVC_NEW_PSW # reenable interrupts
+ lr %r2,%r11 # pass pointer to pt_regs
+ basr %r14,%r1 # call do_notify_resume
+ ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
+ TRACE_IRQS_OFF
+ j io_return
+
+/*
+ * External interrupt handler routine
+ */
+
+ENTRY(ext_int_handler)
+ stck __LC_INT_CLOCK
+ stpt __LC_ASYNC_ENTER_TIMER
+ stm %r8,%r15,__LC_SAVE_AREA_ASYNC
+ l %r12,__LC_THREAD_INFO
+ l %r13,__LC_SVC_NEW_PSW+4
+ lm %r8,%r9,__LC_EXT_OLD_PSW
+ tmh %r8,0x0001 # interrupting from user ?
+ jz ext_skip
+ UPDATE_VTIME %r14,%r15,__LC_ASYNC_ENTER_TIMER
+ext_skip:
+ SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
+ stm %r0,%r7,__PT_R0(%r11)
+ mvc __PT_R8(32,%r11),__LC_SAVE_AREA_ASYNC
+ stm %r8,%r9,__PT_PSW(%r11)
+ TRACE_IRQS_OFF
+ lr %r2,%r11 # pass pointer to pt_regs
+ l %r3,__LC_CPU_ADDRESS # get cpu address + interruption code
+ l %r4,__LC_EXT_PARAMS # get external parameters
+ l %r1,BASED(.Ldo_extint)
+ basr %r14,%r1 # call do_extint
+ j io_return
+
+__critical_end:
+
+/*
+ * Machine check handler routines
+ */
+
+ENTRY(mcck_int_handler)
+ stck __LC_MCCK_CLOCK
+ spt __LC_CPU_TIMER_SAVE_AREA # revalidate cpu timer
+ lm %r0,%r15,__LC_GPREGS_SAVE_AREA # revalidate gprs
+ l %r12,__LC_THREAD_INFO
+ l %r13,__LC_SVC_NEW_PSW+4
+ lm %r8,%r9,__LC_MCK_OLD_PSW
+ tm __LC_MCCK_CODE,0x80 # system damage?
+ jo mcck_panic # yes -> rest of mcck code invalid
+ la %r14,__LC_CPU_TIMER_SAVE_AREA
+ mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
+ tm __LC_MCCK_CODE+5,0x02 # stored cpu timer value valid?
+ jo 3f
+ la %r14,__LC_SYNC_ENTER_TIMER
+ clc 0(8,%r14),__LC_ASYNC_ENTER_TIMER
+ jl 0f
+ la %r14,__LC_ASYNC_ENTER_TIMER
+0: clc 0(8,%r14),__LC_EXIT_TIMER
+ jl 1f
+ la %r14,__LC_EXIT_TIMER
+1: clc 0(8,%r14),__LC_LAST_UPDATE_TIMER
+ jl 2f
+ la %r14,__LC_LAST_UPDATE_TIMER
+2: spt 0(%r14)
+ mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
+3: tm __LC_MCCK_CODE+2,0x09 # mwp + ia of old psw valid?
+ jno mcck_panic # no -> skip cleanup critical
+ tm %r8,0x0001 # interrupting from user ?
+ jz mcck_skip
+ UPDATE_VTIME %r14,%r15,__LC_MCCK_ENTER_TIMER
+mcck_skip:
+ SWITCH_ASYNC __LC_GPREGS_SAVE_AREA+32,__LC_PANIC_STACK,PAGE_SHIFT
+ mvc __PT_R0(64,%r11),__LC_GPREGS_SAVE_AREA
+ stm %r8,%r9,__PT_PSW(%r11)
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ l %r1,BASED(.Ldo_machine_check)
+ lr %r2,%r11 # pass pointer to pt_regs
+ basr %r14,%r1 # call s390_do_machine_check
+ tm __PT_PSW+1(%r11),0x01 # returning to user ?
+ jno mcck_return
+ l %r1,__LC_KERNEL_STACK # switch to kernel stack
+ ahi %r1,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ mvc STACK_FRAME_OVERHEAD(__PT_SIZE,%r1),0(%r11)
+ xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1)
+ la %r11,STACK_FRAME_OVERHEAD(%r15)
+ lr %r15,%r1
+ ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
+ tm __TI_flags+3(%r12),_TIF_MCCK_PENDING
+ jno mcck_return
+ TRACE_IRQS_OFF
+ l %r1,BASED(.Lhandle_mcck)
+ basr %r14,%r1 # call s390_handle_mcck
+ TRACE_IRQS_ON
+mcck_return:
+ mvc __LC_RETURN_MCCK_PSW(8),__PT_PSW(%r11) # move return PSW
+ ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit
+ tm __LC_RETURN_MCCK_PSW+1,0x01 # returning to user ?
+ jno 0f
+ lm %r0,%r15,__PT_R0(%r11)
+ stpt __LC_EXIT_TIMER
+ lpsw __LC_RETURN_MCCK_PSW
+0: lm %r0,%r15,__PT_R0(%r11)
+ lpsw __LC_RETURN_MCCK_PSW
+
+mcck_panic:
+ l %r14,__LC_PANIC_STACK
+ slr %r14,%r15
+ sra %r14,PAGE_SHIFT
+ jz 0f
+ l %r15,__LC_PANIC_STACK
+0: ahi %r15,-(STACK_FRAME_OVERHEAD + __PT_SIZE)
+ j mcck_skip
+
+/*
+ * Restart interruption handler, kick starter for additional CPUs
+ */
+#ifdef CONFIG_SMP
+ __CPUINIT
+ENTRY(restart_int_handler)
+ basr %r1,0
+restart_base:
+ spt restart_vtime-restart_base(%r1)
+ stck __LC_LAST_UPDATE_CLOCK
+ mvc __LC_LAST_UPDATE_TIMER(8),restart_vtime-restart_base(%r1)
+ mvc __LC_EXIT_TIMER(8),restart_vtime-restart_base(%r1)
+ l %r15,__LC_GPREGS_SAVE_AREA+60 # load ksp
+ lctl %c0,%c15,__LC_CREGS_SAVE_AREA # get new ctl regs
+ lam %a0,%a15,__LC_AREGS_SAVE_AREA
+ lm %r6,%r15,__SF_GPRS(%r15)# load registers from clone
+ l %r1,__LC_THREAD_INFO
+ mvc __LC_USER_TIMER(8),__TI_user_timer(%r1)
+ mvc __LC_SYSTEM_TIMER(8),__TI_system_timer(%r1)
+ xc __LC_STEAL_TIMER(8),__LC_STEAL_TIMER
+ ssm __LC_PGM_NEW_PSW # turn dat on, keep irqs off
+ basr %r14,0
+ l %r14,restart_addr-.(%r14)
+ basr %r14,%r14 # call start_secondary
+restart_addr:
+ .long start_secondary
+ .align 8
+restart_vtime:
+ .long 0x7fffffff,0xffffffff
+ .previous
+#else
+/*
+ * If we do not run with SMP enabled, let the new CPU crash ...
+ */
+ENTRY(restart_int_handler)
+ basr %r1,0
+restart_base:
+ lpsw restart_crash-restart_base(%r1)
+ .align 8
+restart_crash:
+ .long 0x000a0000,0x00000000
+restart_go:
+#endif
+
+#
+# PSW restart interrupt handler
+#
+ENTRY(psw_restart_int_handler)
+ st %r15,__LC_SAVE_AREA_RESTART
+ basr %r15,0
+0: l %r15,.Lrestart_stack-0b(%r15) # load restart stack
+ l %r15,0(%r15)
+ ahi %r15,-__PT_SIZE # create pt_regs on stack
+ stm %r0,%r14,__PT_R0(%r15)
+ mvc __PT_R15(4,%r15),__LC_SAVE_AREA_RESTART
+ mvc __PT_PSW(8,%r15),__LC_RST_OLD_PSW # store restart old psw
+ ahi %r15,-STACK_FRAME_OVERHEAD
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ basr %r14,0
+1: l %r14,.Ldo_restart-1b(%r14)
+ basr %r14,%r14
+ basr %r14,0 # load disabled wait PSW if
+2: lpsw restart_psw_crash-2b(%r14) # do_restart returns
+ .align 4
+.Ldo_restart:
+ .long do_restart
+.Lrestart_stack:
+ .long restart_stack
+ .align 8
+restart_psw_crash:
+ .long 0x000a0000,0x00000000 + restart_psw_crash
+
+ .section .kprobes.text, "ax"
+
+#ifdef CONFIG_CHECK_STACK
+/*
+ * The synchronous or the asynchronous stack overflowed. We are dead.
+ * No need to properly save the registers, we are going to panic anyway.
+ * Setup a pt_regs so that show_trace can provide a good call trace.
+ */
+stack_overflow:
+ l %r15,__LC_PANIC_STACK # change to panic stack
+ ahi %r15,-__PT_SIZE # create pt_regs
+ stm %r0,%r7,__PT_R0(%r15)
+ stm %r8,%r9,__PT_PSW(%r15)
+ mvc __PT_R8(32,%r11),0(%r14)
+ lr %r15,%r11
+ ahi %r15,-STACK_FRAME_OVERHEAD
+ l %r1,BASED(1f)
+ xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
+ lr %r2,%r11 # pass pointer to pt_regs
+ br %r1 # branch to kernel_stack_overflow
+1: .long kernel_stack_overflow
+#endif
+
+cleanup_table:
+ .long system_call + 0x80000000
+ .long sysc_do_svc + 0x80000000
+ .long sysc_tif + 0x80000000
+ .long sysc_restore + 0x80000000
+ .long sysc_done + 0x80000000
+ .long io_tif + 0x80000000
+ .long io_restore + 0x80000000
+ .long io_done + 0x80000000
+
+cleanup_critical:
+ cl %r9,BASED(cleanup_table) # system_call
+ jl 0f
+ cl %r9,BASED(cleanup_table+4) # sysc_do_svc
+ jl cleanup_system_call
+ cl %r9,BASED(cleanup_table+8) # sysc_tif
+ jl 0f
+ cl %r9,BASED(cleanup_table+12) # sysc_restore
+ jl cleanup_sysc_tif
+ cl %r9,BASED(cleanup_table+16) # sysc_done
+ jl cleanup_sysc_restore
+ cl %r9,BASED(cleanup_table+20) # io_tif
+ jl 0f
+ cl %r9,BASED(cleanup_table+24) # io_restore
+ jl cleanup_io_tif
+ cl %r9,BASED(cleanup_table+28) # io_done
+ jl cleanup_io_restore
+0: br %r14
+
+cleanup_system_call:
+ # check if stpt has been executed
+ cl %r9,BASED(cleanup_system_call_insn)
+ jh 0f
+ mvc __LC_SYNC_ENTER_TIMER(8),__LC_ASYNC_ENTER_TIMER
+ chi %r11,__LC_SAVE_AREA_ASYNC
+ je 0f
+ mvc __LC_SYNC_ENTER_TIMER(8),__LC_MCCK_ENTER_TIMER
+0: # check if stm has been executed
+ cl %r9,BASED(cleanup_system_call_insn+4)
+ jh 0f
+ mvc __LC_SAVE_AREA_SYNC(32),0(%r11)
+0: # set up saved registers r12, and r13
+ st %r12,16(%r11) # r12 thread-info pointer
+ st %r13,20(%r11) # r13 literal-pool pointer
+ # check if the user time calculation has been done
+ cl %r9,BASED(cleanup_system_call_insn+8)
+ jh 0f
+ l %r10,__LC_EXIT_TIMER
+ l %r15,__LC_EXIT_TIMER+4
+ SUB64 %r10,%r15,__LC_SYNC_ENTER_TIMER
+ ADD64 %r10,%r15,__LC_USER_TIMER
+ st %r10,__LC_USER_TIMER
+ st %r15,__LC_USER_TIMER+4
+0: # check if the system time calculation has been done
+ cl %r9,BASED(cleanup_system_call_insn+12)
+ jh 0f
+ l %r10,__LC_LAST_UPDATE_TIMER
+ l %r15,__LC_LAST_UPDATE_TIMER+4
+ SUB64 %r10,%r15,__LC_EXIT_TIMER
+ ADD64 %r10,%r15,__LC_SYSTEM_TIMER
+ st %r10,__LC_SYSTEM_TIMER
+ st %r15,__LC_SYSTEM_TIMER+4
+0: # update accounting time stamp
+ mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
+ # set up saved register 11
+ l %r15,__LC_KERNEL_STACK
+ ahi %r15,-__PT_SIZE
+ st %r15,12(%r11) # r11 pt_regs pointer
+ # fill pt_regs
+ mvc __PT_R8(32,%r15),__LC_SAVE_AREA_SYNC
+ stm %r0,%r7,__PT_R0(%r15)
+ mvc __PT_PSW(8,%r15),__LC_SVC_OLD_PSW
+ mvc __PT_INT_CODE(4,%r15),__LC_SVC_ILC
+ # setup saved register 15
+ ahi %r15,-STACK_FRAME_OVERHEAD
+ st %r15,28(%r11) # r15 stack pointer
+ # set new psw address and exit
+ l %r9,BASED(cleanup_table+4) # sysc_do_svc + 0x80000000
+ br %r14
+cleanup_system_call_insn:
+ .long system_call + 0x80000000
+ .long sysc_stm + 0x80000000
+ .long sysc_vtime + 0x80000000 + 36
+ .long sysc_vtime + 0x80000000 + 76
+
+cleanup_sysc_tif:
+ l %r9,BASED(cleanup_table+8) # sysc_tif + 0x80000000
+ br %r14
+
+cleanup_sysc_restore:
+ cl %r9,BASED(cleanup_sysc_restore_insn)
+ jhe 0f
+ l %r9,12(%r11) # get saved pointer to pt_regs
+ mvc __LC_RETURN_PSW(8),__PT_PSW(%r9)
+ mvc 0(32,%r11),__PT_R8(%r9)
+ lm %r0,%r7,__PT_R0(%r9)
+0: lm %r8,%r9,__LC_RETURN_PSW
+ br %r14
+cleanup_sysc_restore_insn:
+ .long sysc_done - 4 + 0x80000000
+
+cleanup_io_tif:
+ l %r9,BASED(cleanup_table+20) # io_tif + 0x80000000
+ br %r14
+
+cleanup_io_restore:
+ cl %r9,BASED(cleanup_io_restore_insn)
+ jhe 0f
+ l %r9,12(%r11) # get saved r11 pointer to pt_regs
+ mvc __LC_RETURN_PSW(8),__PT_PSW(%r9)
+ ni __LC_RETURN_PSW+1,0xfd # clear wait state bit
+ mvc 0(32,%r11),__PT_R8(%r9)
+ lm %r0,%r7,__PT_R0(%r9)
+0: lm %r8,%r9,__LC_RETURN_PSW
+ br %r14
+cleanup_io_restore_insn:
+ .long io_done - 4 + 0x80000000
+
+/*
+ * Integer constants
+ */
+ .align 4
+.Lnr_syscalls: .long NR_syscalls
+
+/*
+ * Symbol constants
+ */
+.Ldo_machine_check: .long s390_do_machine_check
+.Lhandle_mcck: .long s390_handle_mcck
+.Ldo_IRQ: .long do_IRQ
+.Ldo_extint: .long do_extint
+.Ldo_signal: .long do_signal
+.Ldo_notify_resume: .long do_notify_resume
+.Ldo_per_trap: .long do_per_trap
+.Ldo_execve: .long do_execve
+.Lexecve_tail: .long execve_tail
+.Ljump_table: .long pgm_check_table
+.Lschedule: .long schedule
+#ifdef CONFIG_PREEMPT
+.Lpreempt_irq: .long preempt_schedule_irq
+#endif
+.Ltrace_enter: .long do_syscall_trace_enter
+.Ltrace_exit: .long do_syscall_trace_exit
+.Lschedule_tail: .long schedule_tail
+.Lsys_call_table: .long sys_call_table
+.Lsysc_per: .long sysc_per + 0x80000000
+#ifdef CONFIG_TRACE_IRQFLAGS
+.Lhardirqs_on: .long trace_hardirqs_on_caller
+.Lhardirqs_off: .long trace_hardirqs_off_caller
+#endif
+#ifdef CONFIG_LOCKDEP
+.Llockdep_sys_exit: .long lockdep_sys_exit
+#endif
+.Lcritical_start: .long __critical_start + 0x80000000
+.Lcritical_length: .long __critical_end - __critical_start
+
+ .section .rodata, "a"
+#define SYSCALL(esa,esame,emu) .long esa
+ .globl sys_call_table
+sys_call_table:
+#include "syscalls.S"
+#undef SYSCALL