fanotify: do not call fanotify_update_object_mask in fanotify_remove_mark

Recalculate masks in fanotify_remove_mark, don't use
fanotify_update_object_mask.  This gets us one step closers to readable
code.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>

1 files changed, 29 insertions, 4 deletions

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 0f25fc20a6a7..96d4ffd72519 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -353,10 +353,26 @@ static void fanotify_update_object_mask(struct fsnotify_group *group,
         }
 }
 
+static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, __u32 mask)
+{
+        __u32 oldmask;
+
+        spin_lock(&fsn_mark->lock);
+        oldmask = fsn_mark->mask;
+        fsn_mark->mask = oldmask & ~mask;
+        spin_unlock(&fsn_mark->lock);
+
+        if (!(oldmask & ~mask))
+                fsnotify_destroy_mark(fsn_mark);
+
+        return mask & oldmask;
+}
+
 static int fanotify_remove_mark(struct fsnotify_group *group, struct inode *inode,
-                                struct vfsmount *mnt, unsigned int flags, __u32 mask)
+                                struct vfsmount *mnt, __u32 mask)
 {
         struct fsnotify_mark *fsn_mark = NULL;
+        __u32 removed;
 
         BUG_ON(inode && mnt);
         BUG_ON(!inode && !mnt);
@@ -371,11 +387,20 @@ static int fanotify_remove_mark(struct fsnotify_group *group, struct inode *inod
         if (!fsn_mark)
                 return -ENOENT;
 
-        fanotify_update_object_mask(group, inode, mnt, fsn_mark, flags, mask);
-
+        removed = fanotify_mark_remove_from_mask(fsn_mark, mask);
         /* matches the fsnotify_find_inode_mark() */
         fsnotify_put_mark(fsn_mark);
 
+        if (removed & group->mask)
+                fsnotify_recalc_group_mask(group);
+        if (inode) {
+                if (removed & inode->i_fsnotify_mask)
+                        fsnotify_recalc_inode_mask(inode);
+        } else if (mnt) {
+                if (removed & mnt->mnt_fsnotify_mask)
+                        fsnotify_recalc_vfsmount_mask(mnt);
+        }
+
         return 0;
 }
 
@@ -568,7 +593,7 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
                 ret = fanotify_add_mark(group, inode, NULL, flags, mask);
                 break;
         case FAN_MARK_REMOVE:
-                ret = fanotify_remove_mark(group, inode, NULL, flags, mask);
+                ret = fanotify_remove_mark(group, inode, NULL, mask);
                 break;
         default:
                 ret = -EINVAL;