Merge tag 'fsnotify_for_v6.9-rc1' of git://git.kernel.org/pub/scm/lin…

…ux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:

 - fsnotify optimizations to reduce cost of fsnotify when nobody is
   watching

 - fix longstanding wart that system could not be suspended when some
   process was waiting for response to fanotify permission event

 - some spelling fixes

* tag 'fsnotify_for_v6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fanotify: allow freeze when waiting response for permission events
  fanotify: Fix misspelling of "writable"
  fsnotify: Fix misspelling of "writable"
  inotify: Fix misspelling of "writable"
  fsnotify: Add fsnotify_sb_has_watchers() helper
  fsnotify: optimize the case of no parent watcher

fs/notify/fanotify/fanotify.c

@@ -228,8 +228,10 @@ static int fanotify_get_response(struct fsnotify_group *group,
 
 	pr_debug("%s: group=%p event=%p\n", __func__, group, event);
 
-	ret = wait_event_killable(group->fanotify_data.access_waitq,
-				  event->state == FAN_EVENT_ANSWERED);
+	ret = wait_event_state(group->fanotify_data.access_waitq,
+				  event->state == FAN_EVENT_ANSWERED,
+				  (TASK_KILLABLE|TASK_FREEZABLE));
+
 	/* Signal pending? */
 	if (ret < 0) {
 		spin_lock(&group->notification_lock);

fs/notify/fsnotify.c

@@ -141,7 +141,7 @@ void __fsnotify_update_child_dentry_flags(struct inode *inode)
 }
 
 /* Are inode/sb/mount interested in parent and name info with this event? */
-static bool fsnotify_event_needs_parent(struct inode *inode, struct mount *mnt,
+static bool fsnotify_event_needs_parent(struct inode *inode, __u32 mnt_mask,
 					__u32 mask)
 {
 	__u32 marks_mask = 0;
@@ -160,13 +160,22 @@ static bool fsnotify_event_needs_parent(struct inode *inode, struct mount *mnt,
 	/* Did either inode/sb/mount subscribe for events with parent/name? */
 	marks_mask |= fsnotify_parent_needed_mask(inode->i_fsnotify_mask);
 	marks_mask |= fsnotify_parent_needed_mask(inode->i_sb->s_fsnotify_mask);
-	if (mnt)
-		marks_mask |= fsnotify_parent_needed_mask(mnt->mnt_fsnotify_mask);
+	marks_mask |= fsnotify_parent_needed_mask(mnt_mask);
 
 	/* Did they subscribe for this event with parent/name info? */
 	return mask & marks_mask;
 }
 
+/* Are there any inode/mount/sb objects that are interested in this event? */
+static inline bool fsnotify_object_watched(struct inode *inode, __u32 mnt_mask,
+					   __u32 mask)
+{
+	__u32 marks_mask = inode->i_fsnotify_mask | mnt_mask |
+			   inode->i_sb->s_fsnotify_mask;
+
+	return mask & marks_mask & ALL_FSNOTIFY_EVENTS;
+}
+
 /*
  * Notify this dentry's parent about a child's events with child name info
  * if parent is watching or if inode/sb/mount are interested in events with
@@ -179,7 +188,7 @@ int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data,
 		      int data_type)
 {
 	const struct path *path = fsnotify_data_path(data, data_type);
-	struct mount *mnt = path ? real_mount(path->mnt) : NULL;
+	__u32 mnt_mask = path ? real_mount(path->mnt)->mnt_fsnotify_mask : 0;
 	struct inode *inode = d_inode(dentry);
 	struct dentry *parent;
 	bool parent_watched = dentry->d_flags & DCACHE_FSNOTIFY_PARENT_WATCHED;
@@ -190,16 +199,13 @@ int __fsnotify_parent(struct dentry *dentry, __u32 mask, const void *data,
 	struct qstr *file_name = NULL;
 	int ret = 0;
 
-	/*
-	 * Do inode/sb/mount care about parent and name info on non-dir?
-	 * Do they care about any event at all?
-	 */
-	if (!inode->i_fsnotify_marks && !inode->i_sb->s_fsnotify_marks &&
-	    (!mnt || !mnt->mnt_fsnotify_marks) && !parent_watched)
+	/* Optimize the likely case of nobody watching this path */
+	if (likely(!parent_watched &&
+		   !fsnotify_object_watched(inode, mnt_mask, mask)))
 		return 0;
 
 	parent = NULL;
-	parent_needed = fsnotify_event_needs_parent(inode, mnt, mask);
+	parent_needed = fsnotify_event_needs_parent(inode, mnt_mask, mask);
 	if (!parent_watched && !parent_needed)
 		goto notify;
 

include/linux/fsnotify.h

@@ -17,6 +17,12 @@
 #include <linux/slab.h>
 #include <linux/bug.h>
 
+/* Are there any inode/mount/sb objects that are being watched at all? */
+static inline bool fsnotify_sb_has_watchers(struct super_block *sb)
+{
+	return atomic_long_read(&sb->s_fsnotify_connectors);
+}
+
 /*
  * Notify this @dir inode about a change in a child directory entry.
  * The directory entry may have turned positive or negative or its inode may
@@ -30,7 +36,7 @@ static inline int fsnotify_name(__u32 mask, const void *data, int data_type,
 				struct inode *dir, const struct qstr *name,
 				u32 cookie)
 {
-	if (atomic_long_read(&dir->i_sb->s_fsnotify_connectors) == 0)
+	if (!fsnotify_sb_has_watchers(dir->i_sb))
 		return 0;
 
 	return fsnotify(mask, data, data_type, dir, name, NULL, cookie);
@@ -44,7 +50,7 @@ static inline void fsnotify_dirent(struct inode *dir, struct dentry *dentry,
 
 static inline void fsnotify_inode(struct inode *inode, __u32 mask)
 {
-	if (atomic_long_read(&inode->i_sb->s_fsnotify_connectors) == 0)
+	if (!fsnotify_sb_has_watchers(inode->i_sb))
 		return;
 
 	if (S_ISDIR(inode->i_mode))
@@ -59,7 +65,7 @@ static inline int fsnotify_parent(struct dentry *dentry, __u32 mask,
 {
 	struct inode *inode = d_inode(dentry);
 
-	if (atomic_long_read(&inode->i_sb->s_fsnotify_connectors) == 0)
+	if (!fsnotify_sb_has_watchers(inode->i_sb))
 		return 0;
 
 	if (S_ISDIR(inode->i_mode)) {

include/linux/fsnotify_backend.h

@@ -31,8 +31,8 @@
 #define FS_ACCESS		0x00000001	/* File was accessed */
 #define FS_MODIFY		0x00000002	/* File was modified */
 #define FS_ATTRIB		0x00000004	/* Metadata changed */
-#define FS_CLOSE_WRITE		0x00000008	/* Writtable file was closed */
-#define FS_CLOSE_NOWRITE	0x00000010	/* Unwrittable file closed */
+#define FS_CLOSE_WRITE		0x00000008	/* Writable file was closed */
+#define FS_CLOSE_NOWRITE	0x00000010	/* Unwritable file closed */
 #define FS_OPEN			0x00000020	/* File was opened */
 #define FS_MOVED_FROM		0x00000040	/* File was moved from X */
 #define FS_MOVED_TO		0x00000080	/* File was moved to Y */

include/uapi/linux/fanotify.h

@@ -8,8 +8,8 @@
 #define FAN_ACCESS		0x00000001	/* File was accessed */
 #define FAN_MODIFY		0x00000002	/* File was modified */
 #define FAN_ATTRIB		0x00000004	/* Metadata changed */
-#define FAN_CLOSE_WRITE		0x00000008	/* Writtable file closed */
-#define FAN_CLOSE_NOWRITE	0x00000010	/* Unwrittable file closed */
+#define FAN_CLOSE_WRITE		0x00000008	/* Writable file closed */
+#define FAN_CLOSE_NOWRITE	0x00000010	/* Unwritable file closed */
 #define FAN_OPEN		0x00000020	/* File was opened */
 #define FAN_MOVED_FROM		0x00000040	/* File was moved from X */
 #define FAN_MOVED_TO		0x00000080	/* File was moved to Y */

include/uapi/linux/inotify.h

@@ -30,8 +30,8 @@ struct inotify_event {
 #define IN_ACCESS		0x00000001	/* File was accessed */
 #define IN_MODIFY		0x00000002	/* File was modified */
 #define IN_ATTRIB		0x00000004	/* Metadata changed */
-#define IN_CLOSE_WRITE		0x00000008	/* Writtable file was closed */
-#define IN_CLOSE_NOWRITE	0x00000010	/* Unwrittable file closed */
+#define IN_CLOSE_WRITE		0x00000008	/* Writable file was closed */
+#define IN_CLOSE_NOWRITE	0x00000010	/* Unwritable file closed */
 #define IN_OPEN			0x00000020	/* File was opened */
 #define IN_MOVED_FROM		0x00000040	/* File was moved from X */
 #define IN_MOVED_TO		0x00000080	/* File was moved to Y */