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-rw-r--r--Documentation/CodingStyle16
-rw-r--r--Documentation/filesystems/Locking3
-rw-r--r--Documentation/filesystems/proc.txt23
-rw-r--r--Documentation/filesystems/vfs.txt4
-rw-r--r--Documentation/sysctl/fs.txt7
-rw-r--r--Documentation/vm/pagemap.txt2
6 files changed, 52 insertions, 3 deletions
diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle
index c58b236bbe04..cb9258b8fd35 100644
--- a/Documentation/CodingStyle
+++ b/Documentation/CodingStyle
@@ -671,8 +671,9 @@ ones already enabled by DEBUG.
Chapter 14: Allocating memory
The kernel provides the following general purpose memory allocators:
-kmalloc(), kzalloc(), kcalloc(), vmalloc(), and vzalloc(). Please refer to
-the API documentation for further information about them.
+kmalloc(), kzalloc(), kmalloc_array(), kcalloc(), vmalloc(), and
+vzalloc(). Please refer to the API documentation for further information
+about them.
The preferred form for passing a size of a struct is the following:
@@ -686,6 +687,17 @@ Casting the return value which is a void pointer is redundant. The conversion
from void pointer to any other pointer type is guaranteed by the C programming
language.
+The preferred form for allocating an array is the following:
+
+ p = kmalloc_array(n, sizeof(...), ...);
+
+The preferred form for allocating a zeroed array is the following:
+
+ p = kcalloc(n, sizeof(...), ...);
+
+Both forms check for overflow on the allocation size n * sizeof(...),
+and return NULL if that occurred.
+
Chapter 15: The inline disease
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index d449e632e6a0..8e2da1e06e3b 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -61,6 +61,7 @@ ata *);
ssize_t (*listxattr) (struct dentry *, char *, size_t);
int (*removexattr) (struct dentry *, const char *);
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
@@ -87,6 +88,8 @@ getxattr: no
listxattr: no
removexattr: 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 912af6ce5626..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
@@ -1578,6 +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 ef19f91a0f12..efd23f481704 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -363,6 +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 (*update_time)(struct inode *, struct timespec *, int);
};
Again, all methods are called without any locks being held, unless
@@ -471,6 +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.
+ 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
========================
diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt
index 88fd7f5c8dcd..13d6166d7a27 100644
--- a/Documentation/sysctl/fs.txt
+++ b/Documentation/sysctl/fs.txt
@@ -225,6 +225,13 @@ a queue must be less or equal then msg_max.
maximum message size value (it is every message queue's attribute set during
its creation).
+/proc/sys/fs/mqueue/msg_default is a read/write file for setting/getting the
+default number of messages in a queue value if attr parameter of mq_open(2) is
+NULL. If it exceed msg_max, the default value is initialized msg_max.
+
+/proc/sys/fs/mqueue/msgsize_default is a read/write file for setting/getting
+the default message size value if attr parameter of mq_open(2) is NULL. If it
+exceed msgsize_max, the default value is initialized msgsize_max.
4. /proc/sys/fs/epoll - Configuration options for the epoll interface
--------------------------------------------------------
diff --git a/Documentation/vm/pagemap.txt b/Documentation/vm/pagemap.txt
index 4600cbe3d6be..7587493c67f1 100644
--- a/Documentation/vm/pagemap.txt
+++ b/Documentation/vm/pagemap.txt
@@ -16,7 +16,7 @@ There are three components to pagemap:
* Bits 0-4 swap type if swapped
* Bits 5-54 swap offset if swapped
* Bits 55-60 page shift (page size = 1<<page shift)
- * Bit 61 reserved for future use
+ * Bit 61 page is file-page or shared-anon
* Bit 62 page swapped
* Bit 63 page present