Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752729AbZAFKGs (ORCPT ); Tue, 6 Jan 2009 05:06:48 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751138AbZAFKGi (ORCPT ); Tue, 6 Jan 2009 05:06:38 -0500 Received: from mail.gmx.net ([213.165.64.20]:52336 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751038AbZAFKGh (ORCPT ); Tue, 6 Jan 2009 05:06:37 -0500 X-Authenticated: #428038 X-Provags-ID: V01U2FsdGVkX19NrfcTRqtN7cB5jgbaqH43DFBhm5mcytXV3YOxBV mUV6cRxVPnvz5c Date: Tue, 6 Jan 2009 11:06:34 +0100 From: Matthias Andree To: kernel list Subject: Re: document ext3 requirements Message-ID: <20090106100634.GA6700@merlin.emma.line.org> Mail-Followup-To: kernel list References: <20090103123813.GA1512@ucw.cz> <495FD5D7.2040907@ribosome.natur.cuni.cz> <20090103222957.GG1666@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20090103222957.GG1666@elf.ucw.cz> X-PGP-Key: http://home.pages.de/~mandree/keys/GPGKEY.asc User-Agent: Mutt/1.5.18 (2008-05-17) X-Y-GMX-Trusted: 0 X-FuHaFi: 0.54 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1728 Lines: 45 On Sat, 03 Jan 2009, Pavel Machek wrote: > On Sat 2009-01-03 22:17:15, Duane Griffin wrote: > > [Fixed top-posting] > > > > 2009/1/3 Martin MOKREJ? : > > > Pavel Machek wrote: > > >> readonly mount does actually write to the media in some cases. Document that. > > >> > > > Can one avoid replay of the journal then if it would be unclean? > > > Just curious. > > > > Nope. If the underlying block device is read-only then mounting the > > filesystem will fail. I tried to fix this some time ago, and have a > > set of patches that almost always work, but "almost always" isn't good > > enough. Unfortunately I never managed to figure out a way to finish it > > off without disgusting hacks or major surgery. > > Uhuh, can you just ignore the journal and mount it anyway? An ext3 file system that needs journal recovery sets one of the ext2 incompatible flags to prevent just that. > ...basically treating it like an ext2? > > ...ok, that will present "old" version of the filesystem to the > user... violating fsync() semantics. > > Still handy for recovering badly broken filesystems, I'd say. While you cannot have that, you'll need to dump the file system (possibly with dd_rescue) to another medium and work on the copy. That's what you should do anyways. ;-) I think if you really want to mount the file system without journal replay, you need to clear the needs-recovery "incompat" flag (on the copy, obviously). -- Matthias Andree -- 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/