[PATCH 05/10] fanotify: add an extra flag to mark_remove_from_mask that indicates wheather a mark should be destroyed

[Andy Whitcroft]

From: Lino Sanfilippo <LinoSanfilippo at gmx.de>

This patch adds an extra flag to mark_remove_from_mask() to inform the caller if
the mark should be destroyed.
With this we dont destroy the mark implicitly in the function itself any more
but let the caller handle it.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo at gmx.de>
Signed-off-by: Eric Paris <eparis at redhat.com>

(cherry-picked from commit d6651e5fee79435ab2b752cd87ed8557ab91a49b git://git.infradead.org/users/eparis/notify.git)
BugLink: http://bugs.launchpad.net/bugs/922906
Signed-off-by: Andy Whitcroft <apw at canonical.com>
---
 fs/notify/fanotify/fanotify_user.c |   19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index a85752d..8424bee 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -513,7 +513,8 @@ out:
 
 static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
 					    __u32 mask,
-					    unsigned int flags)
+					    unsigned int flags,
+					    int *destroy)
 {
 	__u32 oldmask;
 
@@ -527,8 +528,7 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
 	}
 	spin_unlock(&fsn_mark->lock);
 
-	if (!(oldmask & ~mask))
-		fsnotify_destroy_mark(fsn_mark);
+	*destroy = !(oldmask & ~mask);
 
 	return mask & oldmask;
 }
@@ -539,12 +539,17 @@ static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group,
 {
 	struct fsnotify_mark *fsn_mark = NULL;
 	__u32 removed;
+	int destroy_mark;
 
 	fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
 	if (!fsn_mark)
 		return -ENOENT;
 
-	removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
+	removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags,
+						 &destroy_mark);
+	if (destroy_mark)
+		fsnotify_destroy_mark(fsn_mark);
+
 	fsnotify_put_mark(fsn_mark);
 	if (removed & mnt->mnt_fsnotify_mask)
 		fsnotify_recalc_vfsmount_mask(mnt);
@@ -558,12 +563,16 @@ static int fanotify_remove_inode_mark(struct fsnotify_group *group,
 {
 	struct fsnotify_mark *fsn_mark = NULL;
 	__u32 removed;
+	int destroy_mark;
 
 	fsn_mark = fsnotify_find_inode_mark(group, inode);
 	if (!fsn_mark)
 		return -ENOENT;
 
-	removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
+	removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags,
+						 &destroy_mark);
+	if (destroy_mark)
+		fsnotify_destroy_mark(fsn_mark);
 	/* matches the fsnotify_find_inode_mark() */
 	fsnotify_put_mark(fsn_mark);
 	if (removed & inode->i_fsnotify_mask)
-- 
1.7.9.5