fsnotify: fsnotify_add_notify_event should return an event

Rather than the horrific void ** argument and such just to pass the
fanotify_merge event back to the caller of fsnotify_add_notify_event() have
those things return an event if it was different than the event suggusted to
be added.

Signed-off-by: Eric Paris <eparis@redhat.com>

2 files changed, 22 insertions, 17 deletions

diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
index 906b72761b17..73a1106b3542 100644
--- a/fs/notify/inotify/inotify_fsnotify.c
+++ b/fs/notify/inotify/inotify_fsnotify.c
@@ -68,13 +68,11 @@ static bool event_compare(struct fsnotify_event *old, struct fsnotify_event *new
         return false;
 }
 
-static int inotify_merge(struct list_head *list,
-                         struct fsnotify_event *event,
-                         void **arg)
+static struct fsnotify_event *inotify_merge(struct list_head *list,
+                                            struct fsnotify_event *event)
 {
         struct fsnotify_event_holder *last_holder;
         struct fsnotify_event *last_event;
-        int ret = 0;
 
         /* and the list better be locked by something too */
         spin_lock(&event->lock);
@@ -82,11 +80,13 @@ static int inotify_merge(struct list_head *list,
         last_holder = list_entry(list->prev, struct fsnotify_event_holder, event_list);
         last_event = last_holder->event;
         if (event_compare(last_event, event))
-                ret = -EEXIST;
+                fsnotify_get_event(last_event);
+        else
+                last_event = NULL;
 
         spin_unlock(&event->lock);
 
-        return ret;
+        return last_event;
 }
 
 static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_event *event)
@@ -96,7 +96,8 @@ static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_ev
         struct inode *to_tell;
         struct inotify_event_private_data *event_priv;
         struct fsnotify_event_private_data *fsn_event_priv;
-        int wd, ret;
+        struct fsnotify_event *added_event;
+        int wd, ret = 0;
 
         pr_debug("%s: group=%p event=%p to_tell=%p mask=%x\n", __func__, group,
                  event, event->to_tell, event->mask);
@@ -120,14 +121,13 @@ static int inotify_handle_event(struct fsnotify_group *group, struct fsnotify_ev
         fsn_event_priv->group = group;
         event_priv->wd = wd;
 
-        ret = fsnotify_add_notify_event(group, event, fsn_event_priv, inotify_merge, NULL);
-        if (ret) {
+        added_event = fsnotify_add_notify_event(group, event, fsn_event_priv, inotify_merge);
+        if (added_event) {
                 inotify_free_event_priv(fsn_event_priv);
-                /* EEXIST says we tail matched, EOVERFLOW isn't something
-                 * to report up the stack. */
-                if ((ret == -EEXIST) ||
-                    (ret == -EOVERFLOW))
-                        ret = 0;
+                if (!IS_ERR(added_event))
+                        fsnotify_put_event(added_event);
+                else
+                        ret = PTR_ERR(added_event);
         }
 
         if (fsn_mark->mask & IN_ONESHOT)
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 1068e1ca9cb0..a4cd227c4c76 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -516,7 +516,7 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
                                     struct fsnotify_group *group)
 {
         struct inotify_inode_mark *i_mark;
-        struct fsnotify_event *ignored_event;
+        struct fsnotify_event *ignored_event, *notify_event;
         struct inotify_event_private_data *event_priv;
         struct fsnotify_event_private_data *fsn_event_priv;
         int ret;
@@ -538,9 +538,14 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
         fsn_event_priv->group = group;
         event_priv->wd = i_mark->wd;
 
-        ret = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv, NULL, NULL);
-        if (ret)
+        notify_event = fsnotify_add_notify_event(group, ignored_event, fsn_event_priv, NULL);
+        if (notify_event) {
+                if (IS_ERR(notify_event))
+                        ret = PTR_ERR(notify_event);
+                else
+                        fsnotify_put_event(notify_event);
                 inotify_free_event_priv(fsn_event_priv);
+        }
 
 skip_send_ignore: