Some file system events (i.e. FS_ERROR) might not be associated with an
inode or directory. For these, we can retrieve the super block from the
data field. But, since the super_block is available in the data field
on every event type, simplify the code to always retrieve it from there,
through a new helper.
Suggested-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx>
--
Changes since v6:
- Always use data field for superblock retrieval
Changes since v5:
- add fsnotify_data_sb handle to retrieve sb from the data field. (jan)
---
fs/notify/fsnotify.c | 7 +++----
include/linux/fsnotify_backend.h | 15 +++++++++++++++
2 files changed, 18 insertions(+), 4 deletions(-)
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 963e6ce75b96..fde3a1115a17 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -455,16 +455,16 @@ static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info)
* @file_name is relative to
* @file_name: optional file name associated with event
* @inode: optional inode associated with event -
- * either @dir or @inode must be non-NULL.
- * if both are non-NULL event may be reported to both.
+ * If @dir and @inode are both non-NULL, event may be
+ * reported to both.
* @cookie: inotify rename cookie
*/
int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
const struct qstr *file_name, struct inode *inode, u32 cookie)
{
const struct path *path = fsnotify_data_path(data, data_type);
+ struct super_block *sb = fsnotify_data_sb(data, data_type);
struct fsnotify_iter_info iter_info = {};
- struct super_block *sb;
struct mount *mnt = NULL;
struct inode *parent = NULL;
int ret = 0;
@@ -483,7 +483,6 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
*/
parent = dir;
}
- sb = inode->i_sb;
/*
* Optimization: srcu_read_lock() has a memory barrier which can
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index b323d0c4b967..035438fe4a43 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -289,6 +289,21 @@ static inline const struct path *fsnotify_data_path(const void *data,
}
}
+static inline struct super_block *fsnotify_data_sb(const void *data,
+ int data_type)
+{
+ switch (data_type) {
+ case FSNOTIFY_EVENT_INODE:
+ return ((struct inode *)data)->i_sb;
+ case FSNOTIFY_EVENT_DENTRY:
+ return ((struct dentry *)data)->d_sb;
+ case FSNOTIFY_EVENT_PATH:
+ return ((const struct path *)data)->dentry->d_sb;
+ default:
+ return NULL;
+ }
+}
+
enum fsnotify_obj_type {
FSNOTIFY_OBJ_TYPE_INODE,
FSNOTIFY_OBJ_TYPE_PARENT,
--
2.33.0
