android_kernel_xiaomi_sm8350/include/linux/fsnotify.h
Jan Kara ece95912db inotify: send IN_ATTRIB events when link count changes
Currently, no notification event has been sent when inode's link count
changed.  This is inconvenient for the application in some cases:

Suppose you have the following directory structure

    foo/test
    bar/

and you watch test.  If someone does "mv foo/test bar/", you get event
IN_MOVE_SELF and you know something has happened with the file "test".
However if someone does "ln foo/test bar/test" and "rm foo/test" you get no
inotify event for the file "test" (only directories "foo" and "bar" receive
events).

Furthermore it could be argued that link count belongs to file's metadata and
thus IN_ATTRIB should be sent when it changes.

The following patch implements sending of IN_ATTRIB inotify events when link
count of the inode changes, i.e., when a hardlink to the inode is created or
when it is removed.  This event is sent in addition to all the events sent so
far.  In particular, when a last link to a file is removed, IN_ATTRIB event is
sent in addition to IN_DELETE_SELF event.

Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Morten Welinder <mwelinder@gmail.com>
Cc: Robert Love <rlove@google.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:05 -08:00

302 lines
7.4 KiB
C

#ifndef _LINUX_FS_NOTIFY_H
#define _LINUX_FS_NOTIFY_H
/*
* include/linux/fsnotify.h - generic hooks for filesystem notification, to
* reduce in-source duplication from both dnotify and inotify.
*
* We don't compile any of this away in some complicated menagerie of ifdefs.
* Instead, we rely on the code inside to optimize away as needed.
*
* (C) Copyright 2005 Robert Love
*/
#ifdef __KERNEL__
#include <linux/dnotify.h>
#include <linux/inotify.h>
#include <linux/audit.h>
/*
* fsnotify_d_instantiate - instantiate a dentry for inode
* Called with dcache_lock held.
*/
static inline void fsnotify_d_instantiate(struct dentry *entry,
struct inode *inode)
{
inotify_d_instantiate(entry, inode);
}
/*
* fsnotify_d_move - entry has been moved
* Called with dcache_lock and entry->d_lock held.
*/
static inline void fsnotify_d_move(struct dentry *entry)
{
inotify_d_move(entry);
}
/*
* fsnotify_move - file old_name at old_dir was moved to new_name at new_dir
*/
static inline void fsnotify_move(struct inode *old_dir, struct inode *new_dir,
const char *old_name, const char *new_name,
int isdir, struct inode *target, struct dentry *moved)
{
struct inode *source = moved->d_inode;
u32 cookie = inotify_get_cookie();
if (old_dir == new_dir)
inode_dir_notify(old_dir, DN_RENAME);
else {
inode_dir_notify(old_dir, DN_DELETE);
inode_dir_notify(new_dir, DN_CREATE);
}
if (isdir)
isdir = IN_ISDIR;
inotify_inode_queue_event(old_dir, IN_MOVED_FROM|isdir,cookie,old_name,
source);
inotify_inode_queue_event(new_dir, IN_MOVED_TO|isdir, cookie, new_name,
source);
if (target) {
inotify_inode_queue_event(target, IN_DELETE_SELF, 0, NULL, NULL);
inotify_inode_is_dead(target);
}
if (source) {
inotify_inode_queue_event(source, IN_MOVE_SELF, 0, NULL, NULL);
}
audit_inode_child(new_name, moved, new_dir);
}
/*
* fsnotify_nameremove - a filename was removed from a directory
*/
static inline void fsnotify_nameremove(struct dentry *dentry, int isdir)
{
if (isdir)
isdir = IN_ISDIR;
dnotify_parent(dentry, DN_DELETE);
inotify_dentry_parent_queue_event(dentry, IN_DELETE|isdir, 0, dentry->d_name.name);
}
/*
* fsnotify_inoderemove - an inode is going away
*/
static inline void fsnotify_inoderemove(struct inode *inode)
{
inotify_inode_queue_event(inode, IN_DELETE_SELF, 0, NULL, NULL);
inotify_inode_is_dead(inode);
}
/*
* fsnotify_link_count - inode's link count changed
*/
static inline void fsnotify_link_count(struct inode *inode)
{
inotify_inode_queue_event(inode, IN_ATTRIB, 0, NULL, NULL);
}
/*
* fsnotify_create - 'name' was linked in
*/
static inline void fsnotify_create(struct inode *inode, struct dentry *dentry)
{
inode_dir_notify(inode, DN_CREATE);
inotify_inode_queue_event(inode, IN_CREATE, 0, dentry->d_name.name,
dentry->d_inode);
audit_inode_child(dentry->d_name.name, dentry, inode);
}
/*
* fsnotify_link - new hardlink in 'inode' directory
* Note: We have to pass also the linked inode ptr as some filesystems leave
* new_dentry->d_inode NULL and instantiate inode pointer later
*/
static inline void fsnotify_link(struct inode *dir, struct inode *inode, struct dentry *new_dentry)
{
inode_dir_notify(dir, DN_CREATE);
inotify_inode_queue_event(dir, IN_CREATE, 0, new_dentry->d_name.name,
inode);
fsnotify_link_count(inode);
audit_inode_child(new_dentry->d_name.name, new_dentry, dir);
}
/*
* fsnotify_mkdir - directory 'name' was created
*/
static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
{
inode_dir_notify(inode, DN_CREATE);
inotify_inode_queue_event(inode, IN_CREATE | IN_ISDIR, 0,
dentry->d_name.name, dentry->d_inode);
audit_inode_child(dentry->d_name.name, dentry, inode);
}
/*
* fsnotify_access - file was read
*/
static inline void fsnotify_access(struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
u32 mask = IN_ACCESS;
if (S_ISDIR(inode->i_mode))
mask |= IN_ISDIR;
dnotify_parent(dentry, DN_ACCESS);
inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name);
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
}
/*
* fsnotify_modify - file was modified
*/
static inline void fsnotify_modify(struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
u32 mask = IN_MODIFY;
if (S_ISDIR(inode->i_mode))
mask |= IN_ISDIR;
dnotify_parent(dentry, DN_MODIFY);
inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name);
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
}
/*
* fsnotify_open - file was opened
*/
static inline void fsnotify_open(struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
u32 mask = IN_OPEN;
if (S_ISDIR(inode->i_mode))
mask |= IN_ISDIR;
inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name);
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
}
/*
* fsnotify_close - file was closed
*/
static inline void fsnotify_close(struct file *file)
{
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = dentry->d_inode;
const char *name = dentry->d_name.name;
mode_t mode = file->f_mode;
u32 mask = (mode & FMODE_WRITE) ? IN_CLOSE_WRITE : IN_CLOSE_NOWRITE;
if (S_ISDIR(inode->i_mode))
mask |= IN_ISDIR;
inotify_dentry_parent_queue_event(dentry, mask, 0, name);
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
}
/*
* fsnotify_xattr - extended attributes were changed
*/
static inline void fsnotify_xattr(struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
u32 mask = IN_ATTRIB;
if (S_ISDIR(inode->i_mode))
mask |= IN_ISDIR;
inotify_dentry_parent_queue_event(dentry, mask, 0, dentry->d_name.name);
inotify_inode_queue_event(inode, mask, 0, NULL, NULL);
}
/*
* fsnotify_change - notify_change event. file was modified and/or metadata
* was changed.
*/
static inline void fsnotify_change(struct dentry *dentry, unsigned int ia_valid)
{
struct inode *inode = dentry->d_inode;
int dn_mask = 0;
u32 in_mask = 0;
if (ia_valid & ATTR_UID) {
in_mask |= IN_ATTRIB;
dn_mask |= DN_ATTRIB;
}
if (ia_valid & ATTR_GID) {
in_mask |= IN_ATTRIB;
dn_mask |= DN_ATTRIB;
}
if (ia_valid & ATTR_SIZE) {
in_mask |= IN_MODIFY;
dn_mask |= DN_MODIFY;
}
/* both times implies a utime(s) call */
if ((ia_valid & (ATTR_ATIME | ATTR_MTIME)) == (ATTR_ATIME | ATTR_MTIME))
{
in_mask |= IN_ATTRIB;
dn_mask |= DN_ATTRIB;
} else if (ia_valid & ATTR_ATIME) {
in_mask |= IN_ACCESS;
dn_mask |= DN_ACCESS;
} else if (ia_valid & ATTR_MTIME) {
in_mask |= IN_MODIFY;
dn_mask |= DN_MODIFY;
}
if (ia_valid & ATTR_MODE) {
in_mask |= IN_ATTRIB;
dn_mask |= DN_ATTRIB;
}
if (dn_mask)
dnotify_parent(dentry, dn_mask);
if (in_mask) {
if (S_ISDIR(inode->i_mode))
in_mask |= IN_ISDIR;
inotify_inode_queue_event(inode, in_mask, 0, NULL, NULL);
inotify_dentry_parent_queue_event(dentry, in_mask, 0,
dentry->d_name.name);
}
}
#ifdef CONFIG_INOTIFY /* inotify helpers */
/*
* fsnotify_oldname_init - save off the old filename before we change it
*/
static inline const char *fsnotify_oldname_init(const char *name)
{
return kstrdup(name, GFP_KERNEL);
}
/*
* fsnotify_oldname_free - free the name we got from fsnotify_oldname_init
*/
static inline void fsnotify_oldname_free(const char *old_name)
{
kfree(old_name);
}
#else /* CONFIG_INOTIFY */
static inline const char *fsnotify_oldname_init(const char *name)
{
return NULL;
}
static inline void fsnotify_oldname_free(const char *old_name)
{
}
#endif /* ! CONFIG_INOTIFY */
#endif /* __KERNEL__ */
#endif /* _LINUX_FS_NOTIFY_H */