[Labeled-nfs] [PATCH 13/13] NFSD: Label change notification for NFSv4 Server

[Matthew N. Dodd]

J. Bruce Fields wrote:
> On Fri, Nov 16, 2007 at 03:13:02PM -0500, David P. Quigley wrote:
>> NFSv4 Provides methods for detecting changes in attributes and
>> recalling delegations when state has changed on the server. This has
>> been extended to include this functionality for label changes on the
>> server. This patch provides the server implementation for a new
>> callback used to signal relabeling of files.
> 
> What's the goal of these callbacks?
> 
> If you really need a guarantee that all clients will be notified before
> the relabelling operation, then I think you need something stronger than
> inotify.
> 
> If you don't care about synchronous notification, then why not just
> let nfs find out about the change the next time it does an access check
> or something?

That won't happen during vfs_read()/vfs_write().