Merge tag 'fsnotify_for_v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:
 "This implements the fanotify FAN_DIR_MODIFY event.

  This event reports the name in a directory under which a change
  happened and together with the directory filehandle and fstatat()
  allows reliable and efficient implementation of directory
  synchronization"

* tag 'fsnotify_for_v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fanotify: Fix the checks in fanotify_fsid_equal
  fanotify: report name info for FAN_DIR_MODIFY event
  fanotify: record name info for FAN_DIR_MODIFY event
  fanotify: Drop fanotify_event_has_fid()
  fanotify: prepare to report both parent and child fid's
  fanotify: send FAN_DIR_MODIFY event flavor with dir inode and name
  fanotify: divorce fanotify_path_event and fanotify_fid_event
  fanotify: Store fanotify handles differently
  fanotify: Simplify create_fd()
  fanotify: fix merging marks masks with FAN_ONDIR
  fanotify: merge duplicate events on parent and child
  fsnotify: replace inode pointer with an object id
  fsnotify: simplify arguments passing to fsnotify_parent()
  fsnotify: use helpers to access data by data_type
  fsnotify: funnel all dirent events through fsnotify_name()
  fsnotify: factor helpers fsnotify_dentry() and fsnotify_file()
  fsnotify: tidy up FS_ and FAN_ constants

1 files changed, 49 insertions, 21 deletions

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 1915bdba2fad..f0c506405b54 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -47,18 +47,18 @@
 #define FS_OPEN_PERM		0x00010000	/* open event in an permission hook */
 #define FS_ACCESS_PERM		0x00020000	/* access event in a permissions hook */
 #define FS_OPEN_EXEC_PERM	0x00040000	/* open/exec event in a permission hook */
+#define FS_DIR_MODIFY		0x00080000	/* Directory entry was modified */
 
 #define FS_EXCL_UNLINK		0x04000000	/* do not send events if object is unlinked */
-#define FS_ISDIR		0x40000000	/* event occurred against dir */
-#define FS_IN_ONESHOT		0x80000000	/* only send event once */
-
-#define FS_DN_RENAME		0x10000000	/* file renamed */
-#define FS_DN_MULTISHOT		0x20000000	/* dnotify multishot */
-
 /* This inode cares about things that happen to its children.  Always set for
  * dnotify and inotify. */
 #define FS_EVENT_ON_CHILD	0x08000000
 
+#define FS_DN_RENAME		0x10000000	/* file renamed */
+#define FS_DN_MULTISHOT		0x20000000	/* dnotify multishot */
+#define FS_ISDIR		0x40000000	/* event occurred against dir */
+#define FS_IN_ONESHOT		0x80000000	/* only send event once */
+
 #define FS_MOVE			(FS_MOVED_FROM | FS_MOVED_TO)
 
 /*
@@ -67,7 +67,8 @@
  * The watching parent may get an FS_ATTRIB|FS_EVENT_ON_CHILD event
  * when a directory entry inside a child subdir changes.
  */
-#define ALL_FSNOTIFY_DIRENT_EVENTS	(FS_CREATE | FS_DELETE | FS_MOVE)
+#define ALL_FSNOTIFY_DIRENT_EVENTS	(FS_CREATE | FS_DELETE | FS_MOVE | \
+					 FS_DIR_MODIFY)
 
 #define ALL_FSNOTIFY_PERM_EVENTS (FS_OPEN_PERM | FS_ACCESS_PERM | \
 				  FS_OPEN_EXEC_PERM)
@@ -133,8 +134,7 @@ struct fsnotify_ops {
  */
 struct fsnotify_event {
 	struct list_head list;
-	/* inode may ONLY be dereferenced during handle_event(). */
-	struct inode *inode;	/* either the inode the event happened to or its parent */
+	unsigned long objectid;	/* identifier for queue merges */
 };
 
 /*
@@ -213,10 +213,36 @@ struct fsnotify_group {
 	};
 };
 
-/* when calling fsnotify tell it if the data is a path or inode */
-#define FSNOTIFY_EVENT_NONE	0
-#define FSNOTIFY_EVENT_PATH	1
-#define FSNOTIFY_EVENT_INODE	2
+/* When calling fsnotify tell it if the data is a path or inode */
+enum fsnotify_data_type {
+	FSNOTIFY_EVENT_NONE,
+	FSNOTIFY_EVENT_PATH,
+	FSNOTIFY_EVENT_INODE,
+};
+
+static inline const struct inode *fsnotify_data_inode(const void *data,
+						      int data_type)
+{
+	switch (data_type) {
+	case FSNOTIFY_EVENT_INODE:
+		return data;
+	case FSNOTIFY_EVENT_PATH:
+		return d_inode(((const struct path *)data)->dentry);
+	default:
+		return NULL;
+	}
+}
+
+static inline const struct path *fsnotify_data_path(const void *data,
+						    int data_type)
+{
+	switch (data_type) {
+	case FSNOTIFY_EVENT_PATH:
+		return data;
+	default:
+		return NULL;
+	}
+}
 
 enum fsnotify_obj_type {
 	FSNOTIFY_OBJ_TYPE_INODE,
@@ -351,9 +377,10 @@ struct fsnotify_mark {
 /* called from the vfs helpers */
 
 /* main fsnotify call to send events */
-extern int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
-		    const struct qstr *name, u32 cookie);
-extern int __fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask);
+extern int fsnotify(struct inode *to_tell, __u32 mask, const void *data,
+		    int data_type, const struct qstr *name, u32 cookie);
+extern int fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data,
+			   int data_type);
 extern void __fsnotify_inode_delete(struct inode *inode);
 extern void __fsnotify_vfsmount_delete(struct vfsmount *mnt);
 extern void fsnotify_sb_delete(struct super_block *sb);
@@ -500,21 +527,22 @@ extern void fsnotify_finish_user_wait(struct fsnotify_iter_info *iter_info);
 extern bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info);
 
 static inline void fsnotify_init_event(struct fsnotify_event *event,
-				       struct inode *inode)
+				       unsigned long objectid)
 {
 	INIT_LIST_HEAD(&event->list);
-	event->inode = inode;
+	event->objectid = objectid;
 }
 
 #else
 
-static inline int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
-			   const struct qstr *name, u32 cookie)
+static inline int fsnotify(struct inode *to_tell, __u32 mask, const void *data,
+			   int data_type, const struct qstr *name, u32 cookie)
 {
 	return 0;
 }
 
-static inline int __fsnotify_parent(const struct path *path, struct dentry *dentry, __u32 mask)
+static inline int fsnotify_parent(struct dentry *dentry, __u32 mask,
+				  const void *data, int data_type)
 {
 	return 0;
 }