Giving a VFS a chance to be told that an oplock break is occurring

[Jeremy Allison]

On Wed, Mar 28, 2012 at 08:35:56PM +0200, Volker Lendecke wrote:
> On Tue, Mar 27, 2012 at 07:51:09PM -0700, Richard Sharpe wrote:
> > > Definitely widen out to samba-technical... I'm CC:ing vl on the
> > > reply for his thoughts, I know he's spent more time thinking about
> > > async issues in the VFS than I have.
> > 
> > If you are doing read-ahead or write-behind in a VFS module and an
> > oplock break occurs then you need to know about it, it seems to me,
> > either to invalidate or flush ...
> 
> With the current oplock architecture, isn't it possible also
> messaging_register for a MSG_SMB_BREAK_REQUEST with a
> different handler? This way you will get the Samba-internal
> oplock breaks. You could also very cheaply compare
> fsp->oplock_type with a value cached locally in your module.
> If that changes, a break has happened.

Oooh. Good catch - yes that's true.

Jeremy.