Re: which ioctls matter across filesystems

Robert Love
2005-04-29T20:54:56Z

On Fri, 2005-04-29 at 15:47 -0500, Steve French wrote:

> I am not sure - but it is obviously required that inotify can pass over
> CIFS (and probably NFS) since change notification is hardest for the
> user to figure out when they are on a network. I am not sure how the
> filesystem can detect that a new watch is added to one of its inodes -
> it looks like you added an ioctl to a device but I am still reading
> through your latest patch. I was looking for something like an inode
> operation that cifs could hook so the fs could be told when a new watch
> was added or one was changed. In any case I need to construct
> functions somewhat similar to what is in fs/cifs/fcntl.c and need to
> finish/modify CIFSSMBNotify in fs/cifs/cifssmb.c to map the inotify
> flags to the flags available in the CIFS network protocol specifications.
> The existing network protocol support for ChangeNotify is more
> straightforward than you might think and the filter flags & actions that
> I have at my disposal for implementing notify across the network are in
> fs/cifs/cifspdu.h already (search for FILE_ACTION_ and FILE_NOTIFY_ if
> you are curious) but obviously they are similar to what the other Samba
> team guys have already told you.

So a client adds a watch and the server needs to then physically add the
inotify watch?

If you have a user-space, user-space could just add an inotify watch.

But I guess you live entirely in kernel-space? Couldn't we just export
our "add watch" interface to you?

Robert Love