fsnotify: use helpers to access data by data_type

Create helpers to access path and inode from different data types.

Link: https://lore.kernel.org/r/20200319151022.31456-5-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

3 files changed, 14 insertions, 17 deletions

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 5778d1347b35..19ec7a4f4d50 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -151,7 +151,7 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
 {
 	__u32 marks_mask = 0, marks_ignored_mask = 0;
 	__u32 test_mask, user_mask = FANOTIFY_OUTGOING_EVENTS;
-	const struct path *path = data;
+	const struct path *path = fsnotify_data_path(data, data_type);
 	struct fsnotify_mark *mark;
 	int type;
 
@@ -160,7 +160,7 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
 
 	if (!FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
 		/* Do we have path to open a file descriptor? */
-		if (data_type != FSNOTIFY_EVENT_PATH)
+		if (!path)
 			return 0;
 		/* Path type events are only relevant for files and dirs */
 		if (!d_is_reg(path->dentry) && !d_can_lookup(path->dentry))
@@ -269,11 +269,8 @@ static struct inode *fanotify_fid_inode(struct inode *to_tell, u32 event_mask,
 {
 	if (event_mask & ALL_FSNOTIFY_DIRENT_EVENTS)
 		return to_tell;
-	else if (data_type == FSNOTIFY_EVENT_INODE)
-		return (struct inode *)data;
-	else if (data_type == FSNOTIFY_EVENT_PATH)
-		return d_inode(((struct path *)data)->dentry);
-	return NULL;
+
+	return (struct inode *)fsnotify_data_inode(data, data_type);
 }
 
 struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
@@ -284,6 +281,7 @@ 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(inode, mask, data, data_type);
+	const struct path *path = fsnotify_data_path(data, data_type);
 
 	/*
 	 * For queues with unlimited length lost events are not expected and
@@ -324,10 +322,10 @@ init: __maybe_unused
 	if (id && FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
 		/* Report the event without a file identifier on encode error */
 		event->fh_type = fanotify_encode_fid(event, id, gfp, fsid);
-	} else if (data_type == FSNOTIFY_EVENT_PATH) {
+	} else if (path) {
 		event->fh_type = FILEID_ROOT;
-		event->path = *((struct path *)data);
-		path_get(&event->path);
+		event->path = *path;
+		path_get(path);
 	} else {
 		event->fh_type = FILEID_INVALID;
 		event->path.mnt = NULL;
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 46f225580009..a5d6467f89a0 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -318,6 +318,7 @@ static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info)
 int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 	     const struct qstr *file_name, u32 cookie)
 {
+	const struct path *path = fsnotify_data_path(data, data_is);
 	struct fsnotify_iter_info iter_info = {};
 	struct super_block *sb = to_tell->i_sb;
 	struct mount *mnt = NULL;
@@ -325,8 +326,8 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 	int ret = 0;
 	__u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS);
 
-	if (data_is == FSNOTIFY_EVENT_PATH) {
-		mnt = real_mount(((const struct path *)data)->mnt);
+	if (path) {
+		mnt = real_mount(path->mnt);
 		mnt_or_sb_mask |= mnt->mnt_fsnotify_mask;
 	}
 	/* An event "on child" is not intended for a mount/sb mark */
diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c
index d510223d302c..6bb98522bbfd 100644
--- a/fs/notify/inotify/inotify_fsnotify.c
+++ b/fs/notify/inotify/inotify_fsnotify.c
@@ -61,6 +61,7 @@ int inotify_handle_event(struct fsnotify_group *group,
 			 const struct qstr *file_name, u32 cookie,
 			 struct fsnotify_iter_info *iter_info)
 {
+	const struct path *path = fsnotify_data_path(data, data_type);
 	struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info);
 	struct inotify_inode_mark *i_mark;
 	struct inotify_event_info *event;
@@ -73,12 +74,9 @@ int inotify_handle_event(struct fsnotify_group *group,
 		return 0;
 
 	if ((inode_mark->mask & FS_EXCL_UNLINK) &&
-	    (data_type == FSNOTIFY_EVENT_PATH)) {
-		const struct path *path = data;
+	    path && d_unlinked(path->dentry))
+		return 0;
 
-		if (d_unlinked(path->dentry))
-			return 0;
-	}
 	if (file_name) {
 		len = file_name->len;
 		alloc_len += len + 1;