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>

6 files changed, 35 insertions, 39 deletions

diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index 7a42c2ebe28d..2d2eadfb5186 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -70,9 +70,9 @@ static void dnotify_recalc_inode_mask(struct fsnotify_mark *fsn_mark)
  * destroy the dnotify struct if it was not registered to receive multiple
  * events.
  */
-static int dnotify_handle_event(struct fsnotify_group *group,
-				struct inode *inode,
-				u32 mask, const void *data, int data_type,
+static int dnotify_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)
 {
@@ -84,7 +84,7 @@ static int dnotify_handle_event(struct fsnotify_group *group,
 	__u32 test_mask = mask & ~FS_EVENT_ON_CHILD;
 
 	/* not a dir, dnotify doesn't care */
-	if (!S_ISDIR(inode->i_mode))
+	if (!dir && !(mask & FS_ISDIR))
 		return 0;
 
 	if (WARN_ON(fsnotify_iter_vfsmount_mark(iter_info)))
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)) {
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 30628a72ca01..c4ac4d13e10f 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -185,11 +185,9 @@ notify_child:
 }
 EXPORT_SYMBOL_GPL(__fsnotify_parent);
 
-static int send_to_group(struct inode *to_tell,
-			 __u32 mask, const void *data,
-			 int data_is, u32 cookie,
-			 const struct qstr *file_name,
-			 struct fsnotify_iter_info *iter_info)
+static int send_to_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)
 {
 	struct fsnotify_group *group = NULL;
 	__u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS);
@@ -225,15 +223,14 @@ static int send_to_group(struct inode *to_tell,
 		}
 	}
 
-	pr_debug("%s: group=%p to_tell=%p mask=%x marks_mask=%x marks_ignored_mask=%x"
-		 " data=%p data_is=%d cookie=%d\n",
-		 __func__, group, to_tell, mask, marks_mask, marks_ignored_mask,
-		 data, data_is, cookie);
+	pr_debug("%s: group=%p mask=%x marks_mask=%x marks_ignored_mask=%x data=%p data_type=%d dir=%p cookie=%d\n",
+		 __func__, group, mask, marks_mask, marks_ignored_mask,
+		 data, data_type, dir, cookie);
 
 	if (!(test_mask & marks_mask & ~marks_ignored_mask))
 		return 0;
 
-	return group->ops->handle_event(group, to_tell, mask, data, data_is,
+	return group->ops->handle_event(group, mask, data, data_type, dir,
 					file_name, cookie, iter_info);
 }
 
@@ -317,12 +314,13 @@ static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info)
  * out to all of the registered fsnotify_group.  Those groups can then use the
  * notification event in whatever means they feel necessary.
  */
-int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
+int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_type,
 	     const struct qstr *file_name, u32 cookie)
 {
-	const struct path *path = fsnotify_data_path(data, data_is);
+	const struct path *path = fsnotify_data_path(data, data_type);
 	struct fsnotify_iter_info iter_info = {};
 	struct super_block *sb = to_tell->i_sb;
+	struct inode *dir = file_name ? to_tell : NULL;
 	struct mount *mnt = NULL;
 	int ret = 0;
 	__u32 test_mask, marks_mask;
@@ -375,8 +373,8 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 	 * That's why this traversal is so complicated...
 	 */
 	while (fsnotify_iter_select_report_types(&iter_info)) {
-		ret = send_to_group(to_tell, mask, data, data_is, cookie,
-				    file_name, &iter_info);
+		ret = send_to_group(mask, data, data_type, dir, file_name,
+				    cookie, &iter_info);
 
 		if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS))
 			goto out;
diff --git a/fs/notify/inotify/inotify.h b/fs/notify/inotify/inotify.h
index 3f246f7b8a92..4327d0e9c364 100644
--- a/fs/notify/inotify/inotify.h
+++ b/fs/notify/inotify/inotify.h
@@ -24,9 +24,9 @@ static inline struct inotify_event_info *INOTIFY_E(struct fsnotify_event *fse)
 
 extern void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
 					   struct fsnotify_group *group);
-extern int inotify_handle_event(struct fsnotify_group *group,
-				struct inode *inode,
-				u32 mask, const void *data, int data_type,
+extern int inotify_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);
 
diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
index 9b481460a2dc..dfd455798a1b 100644
--- a/fs/notify/inotify/inotify_fsnotify.c
+++ b/fs/notify/inotify/inotify_fsnotify.c
@@ -55,9 +55,8 @@ static int inotify_merge(struct list_head *list,
 	return event_compare(last_event, event);
 }
 
-int inotify_handle_event(struct fsnotify_group *group,
-			 struct inode *inode,
-			 u32 mask, const void *data, int data_type,
+int inotify_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)
 {
@@ -82,7 +81,7 @@ int inotify_handle_event(struct fsnotify_group *group,
 		alloc_len += len + 1;
 	}
 
-	pr_debug("%s: group=%p inode=%p mask=%x\n", __func__, group, inode,
+	pr_debug("%s: group=%p mark=%p mask=%x\n", __func__, group, inode_mark,
 		 mask);
 
 	i_mark = container_of(inode_mark, struct inotify_inode_mark,
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index f88bbcc9efeb..5385d5817dd9 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -490,8 +490,8 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
 					   fsn_mark);
 
 	/* Queue ignore event for the watch */
-	inotify_handle_event(group, NULL, FS_IN_IGNORED, NULL,
-			     FSNOTIFY_EVENT_NONE, NULL, 0, &iter_info);
+	inotify_handle_event(group, FS_IN_IGNORED, NULL, FSNOTIFY_EVENT_NONE,
+			     NULL, NULL, 0, &iter_info);
 
 	i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark);
 	/* remove this mark from the idr */