Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx1.redhat.com ([209.132.183.28]:44047 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754987Ab2CDWbw (ORCPT ); Sun, 4 Mar 2012 17:31:52 -0500 Message-ID: <4F53ED3C.2020209@RedHat.com> Date: Sun, 04 Mar 2012 17:31:24 -0500 From: Steve Dickson MIME-Version: 1.0 To: "Myklebust, Trond" CC: "linux-nfs@vger.kernel.org" Subject: Re: [PATCH] Get normalized paths for comparing NFS export paths References: <1328233332-26020-1-git-send-email-malahal@us.ibm.com> <4F2BC1C0.8070900@panasas.com> <20120203231623.442fefde@notabene.brown> <20120203142945.GA31805@us.ibm.com> <4F2E620F.5090100@panasas.com> <20120207204401.GA31752@us.ibm.com> <4F511B21.1020907@RedHat.com> <20120302192758.GA28389@us.ibm.com> <4F513429.1050209@RedHat.com> <20120302220108.GA17119@us.ibm.com> <4F525741.2060404@RedHat.com> <1330801976.2781.19.camel@lade.trondhjem.org> In-Reply-To: <1330801976.2781.19.camel@lade.trondhjem.org> Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 03/03/2012 02:12 PM, Myklebust, Trond wrote: > On Sat, 2012-03-03 at 12:39 -0500, Steve Dickson wrote: >> >> On 03/02/2012 05:01 PM, Malahal Naineni wrote: >>> Steve Dickson [SteveD@redhat.com] wrote: >>>> So what my patch does is "normalizes" the device name early >>>> on in main, so the correct name used used through the mount >>>> and when its written the mtab. Plus, for better or worses, >>>> since the new device name will always be shorter, I just >>>> reuse/rewrite the memory allocated for the argv vector.. >>>> Meaning there is no allocation... >>> >>> My problem is a bit different. >>> >>> "mount -t nfs4 server:export /mnt" works but umount fails. >>> >>> Notice that there is no '/' in the path! >>> >>> Normalizing or just stripping leading '/'s early won't help with the >>> above problem and since there is already a hack to strip the >>> __trailing__ '/' that kernel adds to /proc/mounts file, I just made the >>> existing hack it a bit better by normalizing. >>> >> How about something like this... It takes on both case early on... >> >> Author: Steve Dickson >> Date: Sat Mar 3 12:31:23 2012 -0500 >> >> mount.nfs: Validate device name syntax >> >> To ensure the device name is found at unmount time strip >> off the multiple '/' or add a '/' if one does not exist. >> >> Signed-off-by: Steve Dickson > > NACK. > > NFSv4 is the only protocol that has a standard mount path syntax, and > that is because the client performs the job of interpreting the path > name and translating it into PUTROOTFH followed by a bunch of LOOKUPs. > IOW: the standard syntax there is the one imposed by the client. > > There is nothing in the NFSv2/v3 MOUNT spec that states that a path > needs to start with '/'. Nor is there even anything in the spec that > states that '/' is required to be used as the directory component > separator. The X/OPEN docs state that '/' is recommended for > portability, but do not make it a requirement. See > http://pubs.opengroup.org/onlinepubs/9629799/chap8.htm#tagcjh_09_02_02_03 > > IOW: I'm perfectly allowed to set up a 'mountd' server that uses '\' or > even something like '|' as a path component separator. This kind of > patch would break the client's existing ability to mount from such a > server. And where does an server like this exist? One that uses '|' as its path component separator?? ;-) Just to be clear, you are ok with striping the multiple slashes, for all protocol versions, but its only kosher to added the leading slash for v4 mounts. Correct? steved.