From: "Duane Griffin" Subject: Re: [RFC, PATCH 6/6] ext3: do not write to the disk when mounting a dirty read-only filesystem Date: Thu, 6 Mar 2008 11:19:03 +0000 Message-ID: References: <20080306071734.GN3616@webber.adilger.int> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, "Theodore Tso" , sct@redhat.com, akpm@linux-foundation.org To: "Andreas Dilger" Return-path: Received: from wf-out-1314.google.com ([209.85.200.174]:8786 "EHLO wf-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754462AbYCFLTG (ORCPT ); Thu, 6 Mar 2008 06:19:06 -0500 Received: by wf-out-1314.google.com with SMTP id 28so2476538wff.4 for ; Thu, 06 Mar 2008 03:19:04 -0800 (PST) In-Reply-To: <20080306071734.GN3616@webber.adilger.int> Content-Disposition: inline Sender: linux-ext4-owner@vger.kernel.org List-ID: On 06/03/2008, Andreas Dilger wrote: > On Mar 06, 2008 01:59 +0000, Duane Griffin wrote: > > NOTE: For now I'm simply preventing filesystems requiring recovery from being > > remounted read-write. This breaks booting with an uncleanly mounted root > > filesystem! > > I was going to ask about this - not being able to remount rw is a serious > problem because many users have only the root filesystem and this > limitation basically prevents this patch from being landable. Yep, I agree. I wanted to post this as an RFC now to get feedback on the overall approach. I'll try and get remount support in there ASAP and post another version. > I'd suggest if the filesystem is going to be remounted read/write that > the journal mapping be discarded and the journal replayed. Depending > on how you do the mapping it may be necessary to invalidate all of the > pages in the cache so that they don't reference the blocks in the journal. That was along the lines I was thinking of, too. Thanks for mentioning invalidating the page cache -- I'll make sure that doesn't get overlooked. > Cheers, Andreas Cheers, Duane. -- "I never could learn to drink that blood and call it wine" - Bob Dylan