From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([59.151.112.132]:61116 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S932820AbbLHGvc (ORCPT ); Tue, 8 Dec 2015 01:51:32 -0500 Subject: Re: [PATCH v2] btrfs: Introduce new mount option to disable tree log replay To: Roman Mamedov References: <1449555033-25075-1-git-send-email-quwenruo@cn.fujitsu.com> <20151208113152.5f8edeaf@natsu> CC: From: Qu Wenruo Message-ID: <56667DC2.6080507@cn.fujitsu.com> Date: Tue, 8 Dec 2015 14:50:42 +0800 MIME-Version: 1.0 In-Reply-To: <20151208113152.5f8edeaf@natsu> Content-Type: text/plain; charset="utf-8"; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: Roman Mamedov wrote on 2015/12/08 11:31 +0500: > On Tue, 8 Dec 2015 14:10:33 +0800 > Qu Wenruo wrote: > >> Introduce a new mount option "nologreplay" to co-operate with "ro" mount >> option to get real readonly mount, like "norecovery" in ext* and xfs. > > Maybe name it "norecovery" too, for simplicity and consistency? That's also our first idea. But the sad fact is, btrfs already has a mount option called "recovery". So "norecovery" here will just be considered as a mount option to disable "recovery", and that will make things more confusing. And finally we choose the name "nologreplay". Thanks, Qu > > The actual effect of "norecovery" in ext* and xfs is to also disable log > replay, but that's an under-the-hood detail not relevant to the user. > > --- > Mount options for ext3 > > norecovery/noload > Don't load the journal on mounting. Note that if the filesystem > was not unmounted cleanly, skipping the journal replay will lead > to the filesystem containing inconsistencies that can lead to > any number of problems. > --- > Mount options for xfs > > norecovery > The filesystem will be mounted without running log recovery. If > the filesystem was not cleanly unmounted, it is likely to be > inconsistent when mounted in norecovery mode. Some files or > directories may not be accessible because of this. Filesystems > mounted norecovery must be mounted read-only or the mount will > fail. > --- >