fsnotify: get rid of fsnotify_destroy_mark_locked()
fsnotify_destroy_mark_locked() is subtle to use because it temporarily
releases group->mark_mutex. To avoid future problems with this
function, split it into two.
fsnotify_detach_mark() is the part that needs group->mark_mutex and
fsnotify_free_mark() is the part that must be called outside of
group->mark_mutex. This way it's much clearer what's going on and we
also avoid some pointless acquisitions of group->mark_mutex.
Signed-off-by: Jan Kara <jack@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index 44523f4..6faaf71 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -154,6 +154,7 @@
struct dnotify_struct *dn;
struct dnotify_struct **prev;
struct inode *inode;
+ bool free = false;
inode = file_inode(filp);
if (!S_ISDIR(inode->i_mode))
@@ -182,11 +183,15 @@
/* nothing else could have found us thanks to the dnotify_groups
mark_mutex */
- if (dn_mark->dn == NULL)
- fsnotify_destroy_mark_locked(fsn_mark, dnotify_group);
+ if (dn_mark->dn == NULL) {
+ fsnotify_detach_mark(fsn_mark);
+ free = true;
+ }
mutex_unlock(&dnotify_group->mark_mutex);
+ if (free)
+ fsnotify_free_mark(fsn_mark);
fsnotify_put_mark(fsn_mark);
}
@@ -362,9 +367,10 @@
spin_unlock(&fsn_mark->lock);
if (destroy)
- fsnotify_destroy_mark_locked(fsn_mark, dnotify_group);
-
+ fsnotify_detach_mark(fsn_mark);
mutex_unlock(&dnotify_group->mark_mutex);
+ if (destroy)
+ fsnotify_free_mark(fsn_mark);
fsnotify_put_mark(fsn_mark);
out_err:
if (new_fsn_mark)