fsnotify: pass dir argument to handle_event() callback

The 'inode' argument to handle_event(), sometimes referred to as
'to_tell' is somewhat obsolete.
It is a remnant from the times when a group could only have an inode mark
associated with an event.

We now pass an iter_info array to the callback, with all marks associated
with an event.

Most backends ignore this argument, with two exceptions:
1. dnotify uses it for sanity check that event is on directory
2. fanotify uses it to report fid of directory on directory entry
   modification events

Remove the 'inode' argument and add a 'dir' argument.
The callback function signature is deliberately changed, because
the meaning of the argument has changed and the arguments have
been documented.

The 'dir' argument is set to when 'file_name' is specified and it is
referring to the directory that the 'file_name' entry belongs to.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 11 insertions, 12 deletions

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 41f5fc9a8f19..e417c64c365b 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -335,11 +335,11 @@ out:
  * FS_ATTRIB reports the child inode even if reported on a watched parent.
  * FS_CREATE reports the modified dir inode and not the created inode.
  */
-static struct inode *fanotify_fid_inode(struct inode *to_tell, u32 event_mask,
-					const void *data, int data_type)
+static struct inode *fanotify_fid_inode(u32 event_mask, const void *data,
+					int data_type, struct inode *dir)
 {
 	if (event_mask & ALL_FSNOTIFY_DIRENT_EVENTS)
-		return to_tell;
+		return dir;
 
 	return fsnotify_data_inode(data, data_type);
 }
@@ -416,14 +416,14 @@ static struct fanotify_event *fanotify_alloc_name_event(struct inode *id,
 }
 
 static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
-						   struct inode *inode, u32 mask,
-						   const void *data, int data_type,
+						   u32 mask, const void *data,
+						   int data_type, struct inode *dir,
 						   const struct qstr *file_name,
 						   __kernel_fsid_t *fsid)
 {
 	struct fanotify_event *event = NULL;
 	gfp_t gfp = GFP_KERNEL_ACCOUNT;
-	struct inode *id = fanotify_fid_inode(inode, mask, data, data_type);
+	struct inode *id = fanotify_fid_inode(mask, data, data_type, dir);
 	const struct path *path = fsnotify_data_path(data, data_type);
 
 	/*
@@ -507,9 +507,9 @@ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info)
 	return fsid;
 }
 
-static int fanotify_handle_event(struct fsnotify_group *group,
-				 struct inode *inode,
-				 u32 mask, const void *data, int data_type,
+static int fanotify_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)
 {
@@ -546,8 +546,7 @@ static int fanotify_handle_event(struct fsnotify_group *group,
 	if (!mask)
 		return 0;
 
-	pr_debug("%s: group=%p inode=%p mask=%x\n", __func__, group, inode,
-		 mask);
+	pr_debug("%s: group=%p mask=%x\n", __func__, group, mask);
 
 	if (fanotify_is_perm_event(mask)) {
 		/*
@@ -565,7 +564,7 @@ static int fanotify_handle_event(struct fsnotify_group *group,
 			return 0;
 	}
 
-	event = fanotify_alloc_event(group, inode, mask, data, data_type,
+	event = fanotify_alloc_event(group, mask, data, data_type, dir,
 				     file_name, &fsid);
 	ret = -ENOMEM;
 	if (unlikely(!event)) {