From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E7356C433E0 for ; Mon, 8 Jun 2020 09:40:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B06672072F for ; Mon, 8 Jun 2020 09:40:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="PzgnHGJV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729206AbgFHJkN (ORCPT ); Mon, 8 Jun 2020 05:40:13 -0400 Received: from mout.gmx.net ([212.227.15.18]:48777 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729172AbgFHJkM (ORCPT ); Mon, 8 Jun 2020 05:40:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1591609202; bh=4izXd3f13y8zmEGnnuaSTYWlmPodQjQ6paYVhGT1i1c=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=PzgnHGJVWqAe67ZarF/ZCpxUq+LhRDxOJzQdNxxwLNEN1SgS/PQjIjVavfn8HK9AA TgYUC+ukW007tJlaxIIT1BN5jpM2eq06XJURa1DsmpiCcTP9XzSBfwMLKiQC3L7lhE OtyhZWV+vW4SGQnMm9NmxHbNsnXbPtnjpvu+7pS0= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.com (mrgmx004 [212.227.17.184]) with ESMTPSA (Nemesis) id 1MwfWa-1ikVrc0kPK-00y7Eq; Mon, 08 Jun 2020 11:40:02 +0200 Subject: Re: [PATCH v7 1/2] btrfs: Introduce "rescue=" mount option To: Anand Jain , dsterba@suse.cz, Qu Wenruo , linux-btrfs@vger.kernel.org References: <20200604071807.61345-1-wqu@suse.com> <20200604071807.61345-2-wqu@suse.com> <3659322f-0687-d179-ff89-f3a303fe2379@oracle.com> <20200605113638.GB27795@twin.jikos.cz> <006ff0d7-517f-e505-e8cd-529029e1e203@oracle.com> From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAU4EEwEIADgCGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1oQAKCRDC PZHzoSX+qCY6CACd+mWu3okGwRKXju6bou+7VkqCaHTdyXwWFTsr+/0ly5nUdDtT3yEVggPJ 3VP70wjlrxUjNjFb6iIvGYxiPOrop1NGwGYvQktgRhaIhALG6rPoSSAhGNjwGVRw0km0PlIN D29BTj/lYEk+jVM1YL0QLgAE1AI3krihg/lp/fQT53wLhR8YZIF8ETXbClQG1vJ0cllPuEEv efKxRyiTSjB+PsozSvYWhXsPeJ+KKjFen7ebE5reQTPFzSHctCdPnoR/4jSPlnTlnEvLeqcD ZTuKfQe1gWrPeevQzgCtgBF/WjIOeJs41klnYzC3DymuQlmFubss0jShLOW8eSOOWhLRuQEN BFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcgaCbPEwhLj 1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj/IrRUUka 68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fNGSsRb+pK EKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0q1eW4Jrv 0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEvABEBAAGJ ATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAKCRDCPZHz oSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gyfmtBnUai fnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsSoCEEynby 72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAkZkA523JG ap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gGUO/iD/T5 oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: Date: Mon, 8 Jun 2020 17:39:58 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.1 MIME-Version: 1.0 In-Reply-To: <006ff0d7-517f-e505-e8cd-529029e1e203@oracle.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="NkPQtwJTcZpcBXNTxS3BCaGd1JwmiCav3" X-Provags-ID: V03:K1:Xkvo9EdMiWiM5nDoXtmQmrNpkQU06BIaaFHETgxxw6OK7guGuSO byDSTpny3OsPH+kGOUXoPiKzY9LI1Q+3QLw2J3gilAjpH+l1v+4+ScYvsv9Tobi9PHvu2oD ZHjuzjOe4xg8m+KY0uIbzb0zMjLxKrGN07x8mftGVlf7xHtvKRxlrXszm8F04kh29S6zwDN 8vXuqWQBoVO/+g6UfKP3A== X-UI-Out-Filterresults: notjunk:1;V03:K0:mkAVODrBYos=:3T6kVELCPXYZujH5Mbj3aw cBpqtZqpccBJigjZHJPXW9fLAH6QCBnNv0Sb4MeHBpXMpQQSsJR+8OihkcQx1/3nk5yS7kQby 32mm7SdNIyXgLusfR9zXW5ErXdlSIqpCdOJ9M4jg2KCT9DUyA7xbgK9vBwR3Duw1R+NWA6+Oa vYWdWUMuzy82yKEpkrQVFF9e5mBnKAu4PJ95bYGFgW2oJWfKgxlmsxmVyBBDZw6eFy7rlGa3b 3LYNQhyrcKkE/1YuFQ3IzSXIBf4BgMpsfGVPhbkEIXTZeSkTIz8E2OihiSY6M3tWCbrUq6vm0 NVmxrAMrsUP6pVFE8wf77djavxbA6vNHyFNo8EsWb+q2gVP5NtjWGz1wfdckJFz54NHnG/ep3 Q/qHEVzCSz7cAEpCKVXCC3t+oCGB5ypg6qLw1jsBLGz7KnwfgrO46FhRqtZ807lSNXGJCvw1j 82q4Z8L8f4h7/27Tley5XxosTMe3ywLZvOUcdkbh/AotX4LNpJpDSnS1KuVZ02hYMUVQVmI1T v2UnJtd6K8s3+sTtfLHym36dxHXGJMKZ1DX61tAbUgxfH739Qvo+oTMkgGI4yzJxB3w0driEC tShtzDQBJQ3zsJtcy0Zd9I02/J0NcjK7OjrDZW2z2Zipgz0kKbgFONNG1L7kmeKOKXPR9azeA PrzKYiyMQ5FzykFUyuqWVPVgyjrjbDUp4OZ5mibLU3yEXQTeD1SdHDE//70oY6mjjntllcJpj DYkbksL9Dt0AW5XNvXSwli+MDvkx4RX0WXEU59Bs3mzC33Bl0tAbMhfjHgKSMHu2gtlUBSoE+ kZ1aNrQ8N1JCqUk5W8LE0pA9sLYgTRBiekJ+BfxP1PI9VDDKxsLBBK9k2kVZ/e0Z3wk82BR5i Lct8wEuvgUMeadVUF33YcHzZclnW1fuKB40YJEepFURtUiNA9c0DE3jPsae69wFTapNsdpjgN op41BLYEW3kNVgFNzve0yRmjSF/Vkeu+yeBVx4cxxEVvuPDFj8x/trFnPqgQ9d+XEAi8FTJ4f 7CYcr0j0ZiVkVt3HbsIb+I2CjaWoQl/o1bhEEjU7XN9h4D95/dgxajIIqFuAPg6zy6w2wravh 20tG8KQbUq7sSQrOjCGrqAbgpJME3RgZuSbG6f1GPfTAu7LTt+J1zXp7ddbiBrCFUz7XnrizC VangjUrY4YMmohBx6rRXjU/c7djOVHLg17zsZGnwJTfMunG1G6GjyXromukelzOczOwVbHdC2 puNh5nGQSD1uHXjrf Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --NkPQtwJTcZpcBXNTxS3BCaGd1JwmiCav3 Content-Type: multipart/mixed; boundary="rrSXec6RYSWcXhNiaGtDF1fpDlcTLNZVq" --rrSXec6RYSWcXhNiaGtDF1fpDlcTLNZVq Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2020/6/8 =E4=B8=8B=E5=8D=884:11, Anand Jain wrote: > On 5/6/20 7:36 pm, David Sterba wrote: >> On Fri, Jun 05, 2020 at 06:04:01PM +0800, Anand Jain wrote: >>> On 4/6/20 3:18 pm, Qu Wenruo wrote: >>>> This patch introduces a new "rescue=3D" mount option group for all t= hose >>>> mount options for data recovery. >>>> >>>> Different rescue sub options are seperated by ':'. E.g >>>> "ro,rescue=3Dnologreplay:usebackuproot". >>>> (The original plan is to use ';', but ';' needs to be escaped/quoted= , >>>> or it will be interpreted by bash) >>> >>> =C2=A0=C2=A0 I fell ':' isn't suitable here. >> >> What do you suggest then? >> >=20 > There isn't any other choice, right? Probably that's the reason for > -o device it is -o device=3Ddev1,device=3Ddev2 still remains separated?= > IMO if there isn't a choice it is ok to leave them separate. >=20 > But as I commented in the other thread instead of > -o rescue=3Dskipbg:another1:another2 why not just -o rescue > and mount thread shall skip the checks that fail and mount the > fs in RO if possible. That would make dependency complex. The skipbg already needs nologreplay and RO, and usebackuproot sometimes doesn't work as expected (in fact, that mount option has fewer success than we thought). I don't want to spend too much code on a salvage mount option group. Thanks, Qu > The dmesg -k must show the checks that > were failed and had to skip to make the RO mount successful. > So, that becomes clear about the errors which lead to the current RO > mount, instead of going through the logs to figure out. This is a more > user-friendly approach as there is one rescue option. But I am not > sure if it is possible? >=20 > Thanks, Anand >=20 >=20 >>>> And obviously, user can specify rescue options one by one like: >>>> "ro,rescue=3Dnologreplay,rescue=3Dusebackuproot" >>> >>> =C2=A0=C2=A0 This should suffice right? >> >> Setting the rescue=3D value separately should be supported, but requir= ing >> to write the option name for each value defeats the purpose to make it= >> compact and user friendly. >> >=20 --rrSXec6RYSWcXhNiaGtDF1fpDlcTLNZVq-- --NkPQtwJTcZpcBXNTxS3BCaGd1JwmiCav3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl7eB24ACgkQwj2R86El /qgv4ggAhOUY4puQ2WySA8yk1UpxQna08dcfM6hjOxchMD2HihEIdZZbSSW9Vz4J slcV1O5uLuJkq7fbjsS2B1TTZp1jXHf+7WRcPd57mT9WdzZbn1QCx7pYH/t9Mn+n 4AokGkGsSielHnF8ao9MqVkFuMElHXp7uyePKnxF/6GF//z/VNAQoDGDllj9pJvP 79CQGOSqU6w1bCvpnZBeecR2ko1CfU8WK/6qy4iLTdrT5iw//hHHSK1vWlcKJMYo eqYDei/r+2pzDFerFECZd0IwPnK0dvhFKSYAWHHtNplokzevrQ6Ds+tDF0VNh3k3 96E7K9Q8wfzi76+UBBOZ8KrJY8tlBA== =GZFC -----END PGP SIGNATURE----- --NkPQtwJTcZpcBXNTxS3BCaGd1JwmiCav3--