From: Erez Zadok Subject: Re: [NFS] Q: directory renames and cache coherency in NFS? Date: Sun, 27 Jan 2008 13:29:26 -0500 Message-ID: <200801271829.m0RITQkQ002462@agora.fsl.cs.sunysb.edu> References: <1201457297.7346.27.camel@heimdal.trondhjem.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Cc: "J. Bruce Fields" , linux-nfs@vger.kernel.org, Erez Zadok , nfs@lists.sourceforge.net, Al Viro To: Trond Myklebust Return-path: Received: from neil.brown.name ([220.233.11.133]:50428 "EHLO neil.brown.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751403AbYA0S3u (ORCPT ); Sun, 27 Jan 2008 13:29:50 -0500 Received: from brown by neil.brown.name with local (Exim 4.63) (envelope-from ) id 1JJCGL-00070R-4G for linux-nfs@vger.kernel.org; Mon, 28 Jan 2008 05:29:49 +1100 In-reply-to: Your message of "Sun, 27 Jan 2008 13:08:17 EST." <1201457297.7346.27.camel-rJ7iovZKK19ZJLDQqaL3InhyD016LWXt@public.gmane.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: In message <1201457297.7346.27.camel-rJ7iovZKK19ZJLDQqaL3InhyD016LWXt@public.gmane.org>, Trond Myklebust writes: > > On Sun, 2008-01-27 at 10:55 -0500, Erez Zadok wrote: > > NFS shares some traits with stackable file systems. Both have some notion > > of "layers": in nfs, it's client -> server -> local f/s; in a stackable f/s > > it's upper -> lower. > > > > I'm trying to understand what are the semantics of NFS when directories are > > renamed on the server while a client is trying to use those directories (I > > follow a similar behavior in unionfs or other stackable f/s). Consider this > > sequence of steps: > > > > 1. client looks up (or revalidates) directory D1 > > 2. server renames D1 to D2 (D2 could be anywhere in the tree) > > 3. client tries to create file F in (the cached) directory D1 > > > > What happens in the last step? Does the client get an ESTALE or some other > > error? Or does it succeed and F gets created in the renamed directory > > (D2/F)? Does the behavior differ b/t nfsv2/3/4? Is it described the RFCs > > or specs? > > The general rule is that an NFSv2/v3/v4 client would expect 3 to succeed > (provided that the user has the required permissions). [...] And by "succeed", you mean that the new file F will be created in D2, right? Thanks, Erez. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs _______________________________________________ Please note that nfs@lists.sourceforge.net is being discontinued. Please subscribe to linux-nfs@vger.kernel.org instead. http://vger.kernel.org/vger-lists.html#linux-nfs