missing code in fcntl_dirnotify

[Steven French <smfrench@austin.rr.com>]

I noticed that fcntl_dirnotify in fs/dnotify.c is missing logic to call
an optional fs specific inode operation for file/directory notify.  
Since directory and file notification to make any sense for many
filesystems (especially network ones) would require that this call
(fcntl F_NOTIFY) to pass through to the filesystem who owns the inode
(to let the particular filesystem know it has to call dnotify_parent on
remote updates to the file/directory) it seems like a bug. Without
notification to the underlying network filesystem, it can not know to
read the updated inode->i_dnotify_mask  Is there any objection why
dnotify_parent should not be added to ksysm.c and to adding an optional
inode_operation for change_notify so filesystems that can support change
notify (cifs, nfs, presumably afs etc.) could do change notify to the
proper kernel routine(dnotify_parent)?