From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: NFS and non-blkdev-backed FS? Date: Sat, 16 Aug 2008 14:11:58 -0400 Message-ID: <20080816181158.GA5787@infradead.org> References: <48A5449F.7050205@nokia.com> <1218808776.3184.89.camel@pmac.infradead.org> <1218809892.7037.3.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Woodhouse , Artem.Bityutskiy@nokia.com, linux-fsdevel@vger.kernel.org To: Trond Myklebust Return-path: Received: from bombadil.infradead.org ([18.85.46.34]:59925 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751837AbYHPSMH (ORCPT ); Sat, 16 Aug 2008 14:12:07 -0400 Content-Disposition: inline In-Reply-To: <1218809892.7037.3.camel@localhost> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Fri, Aug 15, 2008 at 10:18:12AM -0400, Trond Myklebust wrote: > On Fri, 2008-08-15 at 14:59 +0100, David Woodhouse wrote: > > On Fri, 2008-08-15 at 11:55 +0300, Artem Bityutskiy wrote: > > > UBIFS (as e.g. XFS) has a 16-byte UUID in superblock which is > > > supposed to uniquely identify the file-system. I'd like to use > > > this UUID as NFS FSID instead, however, I failed to find how > > > to do this. Any hints how could I do this? > > > > By adding a 'get_fsid()' method to the export_ops structure... > > > > If the uuid can be found by libuuid, then it will automatically be used > as the default identifier by rpc.mount (man 5 exports). There should be > no need for a new export_ops method. We'll need it anyway, for exports not starting at the root of the volume, and we'll need a method to be called when exporting a filesystem to reject it if the filehandle couldn't fit into the space available for the given nfs protocol version.