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=-11.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 038A9C2D0A8 for ; Wed, 23 Sep 2020 09:10:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8EF4520838 for ; Wed, 23 Sep 2020 09:10:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="L6SXRsnv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726415AbgIWJKY (ORCPT ); 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200921144353.31319-8-rgoldwyn@suse.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 21.09.20 г. 17:43 ч., Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues > > fs_info->fs_state is a filesystem bit check as opposed to inode > and can be performed before we begin with write checks. This eliminates > inode lock/unlock in case of error bit is set. > > Signed-off-by: Goldwyn Rodrigues > --- > fs/btrfs/file.c | 21 +++++++++------------ > 1 file changed, 9 insertions(+), 12 deletions(-) > > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index 4c40a2742aab..ca374cb5ffc9 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -1981,6 +1981,15 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, > size_t count; > loff_t oldsize; > > + /* > + * If BTRFS flips readonly due to some impossible error > + * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR), > + * although we have opened a file as writable, we have > + * to stop this write operation to ensure FS consistency. > + */ > + if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) > + return -EROFS; > + nit: Actually can't this check be eliminated altogether or the comment vastly simplified because BTRFS_SUPER_FLAG_ERROR check is performed only during mount so the description in the parantheses is invalid i.e the fs won't flip to RO because BTRFS_SUPER_FLAG_ERROR is now set in the super block. As a matter of fact how is this flag set - because I don't see it set in the kernel code nor in btrfs-progs ?