Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755725Ab0LITe7 (ORCPT ); Thu, 9 Dec 2010 14:34:59 -0500 Received: from mx1.redhat.com ([209.132.183.28]:15291 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752893Ab0LITe6 (ORCPT ); Thu, 9 Dec 2010 14:34:58 -0500 Date: Thu, 9 Dec 2010 14:34:48 -0500 From: Jeff Layton To: Steve French Cc: Suresh Jayaraman , Bernhard Walle , sfrench@samba.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] cifs: Add information about noserverino Message-ID: <20101209143448.5c479e50@barsoom.rdu.redhat.com> In-Reply-To: References: <1291568855-22604-1-git-send-email-bernhard@bwalle.de> <20101206095725.78422138@tlielax.poochiereds.net> <20101206101214.52a24415@tlielax.poochiereds.net> <20101206163506.56232lqqhc5c3co4@webmail.df.eu> <20101206103836.0714369a@tlielax.poochiereds.net> <4D00C02C.4070006@suse.de> <20101209070952.24793c23@barsoom.rdu.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3788 Lines: 86 On Thu, 9 Dec 2010 12:26:39 -0600 Steve French wrote: > On Thu, Dec 9, 2010 at 6:09 AM, Jeff Layton wrote: > > On Thu, 09 Dec 2010 17:10:28 +0530 > > Suresh Jayaraman wrote: > > > >> On 12/06/2010 09:08 PM, Jeff Layton wrote: > >> > On Mon, 06 Dec 2010 16:35:06 +0100 > >> > Bernhard Walle wrote: > >> > > >> >> > >> >> Zitat von Jeff Layton : > >> >> > >> >>> > >> >>> I'm still not sure I like this patch however. It potentially means a > >> >>> lot of printk spam since these things have no ratelimiting. It also > >> >>> doesn't tell me anything about which server might be giving me grief. > >> >>> > >> >>> Maybe this should be turned into a cFYI? > >> >> > >> >> Well, if I see it in the kernel log, it doesn't matter if it's info or > >> >> something else. > >> >> > >> >>> The bottom line though is that running 32-bit applications that were > >> >>> built without -D_FILE_OFFSET_BITS=64 on a 64-bit kernel is a very bad > >> >>> idea. It would be nice to be able to alert users that things aren't > >> >>> working the way they expect, but I'm not sure this is the right place > >> >>> to do that. > >> >> > >> >> Well, but there *are* such application (in my case it was Softmaker Office > >> >> which is a proprietary word processor) and it's quite nice if you know > >> >> how you can workaround it when you encounter such a problem. That's all. > >> >> > >> > > >> > Sure...but this problem is not limited to CIFS. Many modern filesystems > >> > use 64-bit inodes. Running this application on XFS or NFS for instance > >> > is likely to give you the same trouble. You just hit it on CIFS because > >> > the server happened to give you a very large inode number. > >> > > >> > If we're going to add printk's for this situation, it probably ought to > >> > be in a more generic place. > >> > > >> > >> By generic place, did you mean at the VFS level? I think at VFS level, > >> there is little information about the Server or underlying fs and this > >> information doesn't seem too critical that VFS should warn/care much about. > >> > >> May be sticking to a cFYI along with Server detail is a good idea? > >> > > My poing was mainly that there's nothing special about CIFS in this > > regard, other than the fact that servers regularly send us inodes that > > are larger than 2^32. Why should we do this for cifs but not for nfs, > > xfs, ext4, etc? > > > > The filldir function gets a dentry as an argument, so it could > > reasonably generate a printk for this. I'm also not keen on > > the printk recommending noserverino for this. That has its own > > drawbacks. > > > > A cFYI for this sort of thing seems reasonable however. > > I agree that a cFYI is reasonable. The next obvious question is: do > we need to add code to generate unique 32 bit inode numbers > that don't collide (as IIRC Samba does by xor the high and low 32 > bits of the inode number) when the app can't support ino64 > I would prefer not to go back to noserverino since that has worse > drawbacks. > Right, the fact that noserverino works around this is really just due to an implementation detail of iunique(). That should probably be discouraged as a solution since it's not guaranteed to be a workaround in the future. If we did add such a switch, I'd suggest that we pattern it after what NFS did for this. They added an "enable_ino64" module parameter a couple of years ago that defaults to "true". -- Jeff Layton -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/