[RFC PATCH] network fs notification

[Miklos Szeredi <miklos@szeredi.hu>]

This is a really really trivial first iteration, but I think it's enough to
try out CIFS notification support.  Doesn't deal with mark deletion, but
that's best effort anyway: fsnotify() will filter out unneeded events.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
---
 fs/notify/fanotify/fanotify_user.c |    6 +++++-
 fs/notify/inotify/inotify_user.c   |    2 ++
 include/linux/fs.h                 |    1 +
 3 files changed, 8 insertions(+), 1 deletion(-)

--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -1041,9 +1041,13 @@ static int do_fanotify_mark(int fanotify
 		else if (mark_type == FAN_MARK_FILESYSTEM)
 			ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask,
 						   flags, fsid);
-		else
+		else {
 			ret = fanotify_add_inode_mark(group, inode, mask,
 						      flags, fsid);
+
+			if (!ret && inode->i_op->notify_update)
+				inode->i_op->notify_update(inode);
+		}
 		break;
 	case FAN_MARK_REMOVE:
 		if (mark_type == FAN_MARK_MOUNT)
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -754,6 +754,8 @@ SYSCALL_DEFINE3(inotify_add_watch, int,
 
 	/* create/update an inode mark */
 	ret = inotify_update_watch(group, inode, mask);
+	if (!ret && inode->i_op->notify_update)
+		inode->i_op->notify_update(inode);
 	path_put(&path);
 fput_and_out:
 	fdput(f);
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1852,6 +1852,7 @@ struct inode_operations {
 			   umode_t create_mode);
 	int (*tmpfile) (struct inode *, struct dentry *, umode_t);
 	int (*set_acl)(struct inode *, struct posix_acl *, int);
+	void (*notify_update)(struct inode *inode);
 } ____cacheline_aligned;
 
 static inline ssize_t call_read_iter(struct file *file, struct kiocb *kio,