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=-2.2 required=3.0 tests=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 80A7BC2D0CE for ; Tue, 21 Jan 2020 15:17:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 577FE21569 for ; Tue, 21 Jan 2020 15:17:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728811AbgAUPRK (ORCPT ); Tue, 21 Jan 2020 10:17:10 -0500 Received: from mx2.suse.de ([195.135.220.15]:47072 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727508AbgAUPRK (ORCPT ); Tue, 21 Jan 2020 10:17:10 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 0BD53AC4A; Tue, 21 Jan 2020 15:17:07 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 8EBCADA738; Tue, 21 Jan 2020 16:16:51 +0100 (CET) Date: Tue, 21 Jan 2020 16:16:51 +0100 From: David Sterba To: Nikolay Borisov Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH 3/4] btrfs: Handle another split brain scenario with metadata uuid feature Message-ID: <20200121151651.GW3929@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Nikolay Borisov , linux-btrfs@vger.kernel.org References: <20200110121135.7386-1-nborisov@suse.com> <20200110121135.7386-4-nborisov@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200110121135.7386-4-nborisov@suse.com> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Fri, Jan 10, 2020 at 02:11:34PM +0200, Nikolay Borisov wrote: > list_for_each_entry(fs_devices, &fs_uuids, fs_list) { > - if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, > - BTRFS_FSID_SIZE) != 0 && > - memcmp(fs_devices->metadata_uuid, disk_super->metadata_uuid, > - BTRFS_FSID_SIZE) == 0 && > - memcmp(fs_devices->fsid, disk_super->fsid, > - BTRFS_FSID_SIZE) != 0) { > + bool changed_fsdevices = > + memcmp(fs_devices->metadata_uuid, fs_devices->fsid, > + BTRFS_FSID_SIZE) != 0 && > + memcmp(fs_devices->metadata_uuid, > + disk_super->metadata_uuid, BTRFS_FSID_SIZE) == 0 && > + memcmp(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE) != 0; > + > + bool unchanged_fsdevices = > + memcmp(fs_devices->metadata_uuid, fs_devices->fsid, > + BTRFS_FSID_SIZE) == 0 && > + memcmp(fs_devices->fsid, disk_super->metadata_uuid, BTRFS_FSID_SIZE) == 0; > + if (changed_fsdevices || unchanged_fsdevices) > return fs_devices; This is ugly, I've converted it to if (memcmp) and dropped the variables.