[PATCH 5/9] fsnotify: simplify dir argument to handle_event()

[Amir Goldstein <amir73il@gmail.com>]

The meaning of dir argument could be simplified a lot to just the base
of file_name it we let the only backends that care about it (fanotify and
dnotify) cope with the case of NULL file_name themselves, which is easy.

This will make dir argument meaning generic enough so we can use the
same argument for fsnotify() without causing confusion.

Fixes: e2c9d9039c3f ("fsnotify: pass dir argument to handle_event() callback")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
 fs/notify/dnotify/dnotify.c      | 2 +-
 fs/notify/fanotify/fanotify.c    | 7 ++++---
 fs/notify/fsnotify.c             | 2 +-
 include/linux/fsnotify_backend.h | 4 +---
 4 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/fs/notify/dnotify/dnotify.c b/fs/notify/dnotify/dnotify.c
index 305e5559560a..ca78d3f78da8 100644
--- a/fs/notify/dnotify/dnotify.c
+++ b/fs/notify/dnotify/dnotify.c
@@ -112,7 +112,7 @@ static int dnotify_handle_event(struct fsnotify_group *group, u32 mask,
 	struct fsnotify_mark *child_mark = fsnotify_iter_child_mark(iter_info);
 
 	/* not a dir, dnotify doesn't care */
-	if (!dir)
+	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 36ea0cd6387e..03e3dce2a97c 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -245,7 +245,7 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
 			return 0;
 	} else if (!(fid_mode & FAN_REPORT_FID)) {
 		/* Do we have a directory inode to report? */
-		if (!dir)
+		if (!dir && !(event_mask & FS_ISDIR))
 			return 0;
 	}
 
@@ -525,12 +525,13 @@ static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
 	struct fanotify_event *event = NULL;
 	gfp_t gfp = GFP_KERNEL_ACCOUNT;
 	struct inode *id = fanotify_fid_inode(mask, data, data_type, dir);
+	struct inode *dirid = fanotify_dfid_inode(mask, data, data_type, dir);
 	const struct path *path = fsnotify_data_path(data, data_type);
 	unsigned int fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS);
 	struct inode *child = NULL;
 	bool name_event = false;
 
-	if ((fid_mode & FAN_REPORT_DIR_FID) && dir) {
+	if ((fid_mode & FAN_REPORT_DIR_FID) && dirid) {
 		/*
 		 * With both flags FAN_REPORT_DIR_FID and FAN_REPORT_FID, we
 		 * report the child fid for events reported on a non-dir child
@@ -540,7 +541,7 @@ static struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
 		    (mask & FAN_EVENT_ON_CHILD) && !(mask & FAN_ONDIR))
 			child = id;
 
-		id = fanotify_dfid_inode(mask, data, data_type, dir);
+		id = dirid;
 
 		/*
 		 * We record file name only in a group with FAN_REPORT_NAME
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 277af3d5efce..834775f61f6b 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -365,7 +365,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_type,
 	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 = S_ISDIR(to_tell->i_mode) ? to_tell : NULL;
+	struct inode *dir = file_name ? to_tell : NULL;
 	struct mount *mnt = NULL;
 	struct inode *child = NULL;
 	int ret = 0;
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 9bd75d0582b4..d94a50e0445a 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -123,9 +123,7 @@ struct mem_cgroup;
  * @data_type:	type of object for fanotify_data_XXX() accessors
  * @dir:	optional directory associated with event -
  *		if @file_name is not NULL, this is the directory that
- *		@file_name is relative to. Otherwise, @dir is the object
- *		inode if event happened on directory and NULL if event
- *		happenned on a non-directory.
+ *		@file_name is relative to
  * @file_name:	optional file name associated with event
  * @cookie:	inotify rename cookie
  * @iter_info:	array of marks from this group that are interested in the event
-- 
2.17.1