fsnotify: create method handle_inode_event() in fsnotify_operations

The method handle_event() grew a lot of complexity due to the design of
fanotify and merging of ignore masks.

Most backends do not care about this complex functionality, so we can hide
this complexity from them.

Introduce a method handle_inode_event() that serves those backends and
passes a single inode mark and less arguments.

This change converts all backends except fanotify and inotify to use the
simplified handle_inode_event() method.  In pricipal, inotify could have
also used the new method, but that would require passing more arguments
on the simple helper (data, data_type, cookie), so we leave it with the
handle_event() method.

Link: https://lore.kernel.org/r/20200722125849.17418-9-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 16 insertions, 3 deletions

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 32104cfc27a5..f8529a3a2923 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -128,17 +128,30 @@ struct mem_cgroup;
  * @cookie:	inotify rename cookie
  * @iter_info:	array of marks from this group that are interested in the event
  *
+ * handle_inode_event - simple variant of handle_event() for groups that only
+ *		have inode marks and don't have ignore mask
+ * @mark:	mark to notify
+ * @mask:	event type and flags
+ * @inode:	inode that event happened on
+ * @dir:	optional directory associated with event -
+ *		if @file_name is not NULL, this is the directory that
+ *		@file_name is relative to.
+ * @file_name:	optional file name associated with event
+ *
  * free_group_priv - called when a group refcnt hits 0 to clean up the private union
  * freeing_mark - called when a mark is being destroyed for some reason.  The group
- * 		MUST be holding a reference on each mark and that reference must be
- * 		dropped in this function.  inotify uses this function to send
- * 		userspace messages that marks have been removed.
+ *		MUST be holding a reference on each mark and that reference must be
+ *		dropped in this function.  inotify uses this function to send
+ *		userspace messages that marks have been removed.
  */
 struct fsnotify_ops {
 	int (*handle_event)(struct fsnotify_group *group, u32 mask,
 			    const void *data, int data_type, struct inode *dir,
 			    const struct qstr *file_name, u32 cookie,
 			    struct fsnotify_iter_info *iter_info);
+	int (*handle_inode_event)(struct fsnotify_mark *mark, u32 mask,
+			    struct inode *inode, struct inode *dir,
+			    const struct qstr *file_name);
 	void (*free_group_priv)(struct fsnotify_group *group);
 	void (*freeing_mark)(struct fsnotify_mark *mark, struct fsnotify_group *group);
 	void (*free_event)(struct fsnotify_event *event);