[PATCH] inotify
inotify is intended to correct the deficiencies of dnotify, particularly
its inability to scale and its terrible user interface:
* dnotify requires the opening of one fd per each directory
that you intend to watch. This quickly results in too many
open files and pins removable media, preventing unmount.
* dnotify is directory-based. You only learn about changes to
directories. Sure, a change to a file in a directory affects
the directory, but you are then forced to keep a cache of
stat structures.
* dnotify's interface to user-space is awful. Signals?
inotify provides a more usable, simple, powerful solution to file change
notification:
* inotify's interface is a system call that returns a fd, not SIGIO.
You get a single fd, which is select()-able.
* inotify has an event that says "the filesystem that the item
you were watching is on was unmounted."
* inotify can watch directories or files.
Inotify is currently used by Beagle (a desktop search infrastructure),
Gamin (a FAM replacement), and other projects.
See Documentation/filesystems/inotify.txt.
Signed-off-by: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/attr.c b/fs/attr.c
index c3c76fe..b1796fb 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -10,7 +10,7 @@
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/smp_lock.h>
-#include <linux/dnotify.h>
+#include <linux/fsnotify.h>
#include <linux/fcntl.h>
#include <linux/quotaops.h>
#include <linux/security.h>
@@ -107,31 +107,8 @@
out:
return error;
}
-
EXPORT_SYMBOL(inode_setattr);
-int setattr_mask(unsigned int ia_valid)
-{
- unsigned long dn_mask = 0;
-
- if (ia_valid & ATTR_UID)
- dn_mask |= DN_ATTRIB;
- if (ia_valid & ATTR_GID)
- dn_mask |= DN_ATTRIB;
- if (ia_valid & ATTR_SIZE)
- dn_mask |= DN_MODIFY;
- /* both times implies a utime(s) call */
- if ((ia_valid & (ATTR_ATIME|ATTR_MTIME)) == (ATTR_ATIME|ATTR_MTIME))
- dn_mask |= DN_ATTRIB;
- else if (ia_valid & ATTR_ATIME)
- dn_mask |= DN_ACCESS;
- else if (ia_valid & ATTR_MTIME)
- dn_mask |= DN_MODIFY;
- if (ia_valid & ATTR_MODE)
- dn_mask |= DN_ATTRIB;
- return dn_mask;
-}
-
int notify_change(struct dentry * dentry, struct iattr * attr)
{
struct inode *inode = dentry->d_inode;
@@ -197,11 +174,9 @@
if (ia_valid & ATTR_SIZE)
up_write(&dentry->d_inode->i_alloc_sem);
- if (!error) {
- unsigned long dn_mask = setattr_mask(ia_valid);
- if (dn_mask)
- dnotify_parent(dentry, dn_mask);
- }
+ if (!error)
+ fsnotify_change(dentry, ia_valid);
+
return error;
}