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-rw-r--r--Documentation/filesystems/Locking5
-rw-r--r--Documentation/filesystems/proc.txt25
-rw-r--r--Documentation/filesystems/vfs.txt17
3 files changed, 40 insertions, 7 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index 4fca82e5276e..8e2da1e06e3b 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -60,8 +60,8 @@ ata *);
ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
ssize_t (*listxattr) (struct dentry *, char *, size_t);
int (*removexattr) (struct dentry *, const char *);
- void (*truncate_range)(struct inode *, loff_t, loff_t);
int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len);
+ void (*update_time)(struct inode *, struct timespec *, int);
locking rules:
all may block
@@ -87,8 +87,9 @@ setxattr: yes
getxattr: no
listxattr: no
removexattr: yes
-truncate_range: yes
fiemap: no
+update_time: no
+
Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
victim.
cross-directory ->rename() has (per-superblock) ->s_vfs_rename_sem.
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index ef088e55ab2e..fb0a6aeb936c 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -40,6 +40,7 @@ Table of Contents
3.4 /proc/<pid>/coredump_filter - Core dump filtering settings
3.5 /proc/<pid>/mountinfo - Information about mounts
3.6 /proc/<pid>/comm & /proc/<pid>/task/<tid>/comm
+ 3.7 /proc/<pid>/task/<tid>/children - Information about task children
4 Configuring procfs
4.1 Mount options
@@ -310,6 +311,11 @@ Table 1-4: Contents of the stat files (as of 2.6.30-rc7)
start_data address above which program data+bss is placed
end_data address below which program data+bss is placed
start_brk address above which program heap can be expanded with brk()
+ arg_start address above which program command line is placed
+ arg_end address below which program command line is placed
+ env_start address above which program environment is placed
+ env_end address below which program environment is placed
+ exit_code the thread's exit_code in the form reported by the waitpid system call
..............................................................................
The /proc/PID/maps file containing the currently mapped memory regions and
@@ -743,6 +749,7 @@ Committed_AS: 100056 kB
VmallocTotal: 112216 kB
VmallocUsed: 428 kB
VmallocChunk: 111088 kB
+AnonHugePages: 49152 kB
MemTotal: Total usable ram (i.e. physical ram minus a few reserved
bits and the kernel binary code)
@@ -776,6 +783,7 @@ VmallocChunk: 111088 kB
Dirty: Memory which is waiting to get written back to the disk
Writeback: Memory which is actively being written back to the disk
AnonPages: Non-file backed pages mapped into userspace page tables
+AnonHugePages: Non-file backed huge pages mapped into userspace page tables
Mapped: files which have been mmaped, such as libraries
Slab: in-kernel data structures cache
SReclaimable: Part of Slab, that might be reclaimed, such as caches
@@ -1576,6 +1584,23 @@ then the kernel's TASK_COMM_LEN (currently 16 chars) will result in a truncated
comm value.
+3.7 /proc/<pid>/task/<tid>/children - Information about task children
+-------------------------------------------------------------------------
+This file provides a fast way to retrieve first level children pids
+of a task pointed by <pid>/<tid> pair. The format is a space separated
+stream of pids.
+
+Note the "first level" here -- if a child has own children they will
+not be listed here, one needs to read /proc/<children-pid>/task/<tid>/children
+to obtain the descendants.
+
+Since this interface is intended to be fast and cheap it doesn't
+guarantee to provide precise results and some children might be
+skipped, especially if they've exited right after we printed their
+pids, so one need to either stop or freeze processes being inspected
+if precise results are needed.
+
+
------------------------------------------------------------------------------
Configuring procfs
------------------------------------------------------------------------------
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 0d0492028082..efd23f481704 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -363,7 +363,7 @@ struct inode_operations {
ssize_t (*getxattr) (struct dentry *, const char *, void *, size_t);
ssize_t (*listxattr) (struct dentry *, char *, size_t);
int (*removexattr) (struct dentry *, const char *);
- void (*truncate_range)(struct inode *, loff_t, loff_t);
+ void (*update_time)(struct inode *, struct timespec *, int);
};
Again, all methods are called without any locks being held, unless
@@ -472,9 +472,9 @@ otherwise noted.
removexattr: called by the VFS to remove an extended attribute from
a file. This method is called by removexattr(2) system call.
- truncate_range: a method provided by the underlying filesystem to truncate a
- range of blocks , i.e. punch a hole somewhere in a file.
-
+ update_time: called by the VFS to update a specific time or the i_version of
+ an inode. If this is not defined the VFS will update the inode itself
+ and call mark_inode_dirty_sync.
The Address Space Object
========================
@@ -760,7 +760,7 @@ struct file_operations
----------------------
This describes how the VFS can manipulate an open file. As of kernel
-2.6.22, the following members are defined:
+3.5, the following members are defined:
struct file_operations {
struct module *owner;
@@ -790,6 +790,8 @@ struct file_operations {
int (*flock) (struct file *, int, struct file_lock *);
ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, size_t, unsigned int);
ssize_t (*splice_read)(struct file *, struct pipe_inode_info *, size_t, unsigned int);
+ int (*setlease)(struct file *, long arg, struct file_lock **);
+ long (*fallocate)(struct file *, int mode, loff_t offset, loff_t len);
};
Again, all methods are called without any locks being held, unless
@@ -858,6 +860,11 @@ otherwise noted.
splice_read: called by the VFS to splice data from file to a pipe. This
method is used by the splice(2) system call
+ setlease: called by the VFS to set or release a file lock lease.
+ setlease has the file_lock_lock held and must not sleep.
+
+ fallocate: called by the VFS to preallocate blocks or punch a hole.
+
Note that the file operations are implemented by the specific
filesystem in which the inode resides. When opening a device node
(character or block special) most filesystems will call special