On Thu, Jul 28, 2011 at 10:27:58PM -0400, J. Bruce Fields wrote: > On Thu, Jul 21, 2011 at 12:35:20PM -0400, J. Bruce Fields wrote: > > On Wed, Jul 20, 2011 at 05:15:42PM -0700, Jeremy Allison wrote: > > > On Wed, Jul 20, 2011 at 08:07:58PM -0400, J. Bruce Fields wrote: > > > > So it's a question about the protocols samba implements: > > > > > > > > - Do they allow an atomic downgrade from an exclusive to a > > > > shared oplock? (Or to a level 2 oplock, or whatever the right > > > > term is). > > > > > > Yes. Exclusive can go to level 2 - in fact that's the default > > > downgrade we do (unless an smb.conf option explicity denies it). > > > > > > > - If so, can that happen as a response to a conflicting open? > > > > (So, if you're holding an exclusive oplock, and a conflicting > > > > open comes in, can the server-to-client break message say "now > > > > you're getting a shared oplock instead"? Or is the client > > > > left without any oplock until it requests a new one?) > > > > > > Yes, this can happen. > > > > > > In SMB, we only break to no lease when a write request comes > > > in on a exclusive or level2 oplock (read-lease) handle. > > > > Ok, thanks, that means we need a more complicated fix here--I'll work on > > that.... > > My attempt follows. Lightly tested. > > I'll probably try writing a test or two for it, then queueing up > something like this for 3.2, absent objections. Second take follows, this time after a little more testing (lease_tests.c from git://linux-nfs.org/~bfields/lock-tests.git), some bug fixes, and minor simplification of the logic. This is what I intend to queue up for 3.2. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
