From: "J. Bruce Fields" Subject: Re: nfs4 write delegation status Date: Thu, 23 Jul 2009 09:00:39 -0400 Message-ID: <20090723130039.GB22626@fieldses.org> References: <20090722163810.GB4491@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: linux-nfs@vger.kernel.org, nfsv4@linux-nfs.org, linux-nfs-owner@vger.kernel.org To: Eric Veith Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nfsv4-bounces@linux-nfs.org Errors-To: nfsv4-bounces@linux-nfs.org List-ID: On Thu, Jul 23, 2009 at 10:12:05AM +0200, Eric Veith wrote: > Hello, > > > I really don't want to enable write delegations until we figure out how > > to enforce them correctly against local (non-nfs) users of the exported > > filesystem as well. In addition to breaking delegations on read opens, > > that means breaking delegations or doing a cb_getattr on operations like > > stat. > > do you know whether there are local FS where the maintainers at least plan > to incorporate delegations? Local filesystems don't need support from the filesystem itself; the only modifications necessary should be to the vfs. We have patches that do that for read delegations: http://git.linux-nfs.org/?p=bfields/linux-topics.git;a=shortlog;h=refs/heads/leases but they still have a few problems. I hope to get them out for review soon. Write delegations are more difficult. Distributed filesystems will also be harder. --b.