From patchwork Sat Jul 31 07:42:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 12412345 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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 0031BC4338F for ; Sat, 31 Jul 2021 07:42:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D76FA60EE6 for ; Sat, 31 Jul 2021 07:42:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232225AbhGaHmw (ORCPT ); Sat, 31 Jul 2021 03:42:52 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:47460 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229703AbhGaHmv (ORCPT ); Sat, 31 Jul 2021 03:42:51 -0400 Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 588FD2240F; Sat, 31 Jul 2021 07:42:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1627717365; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=49genXamuWPUfnqIYM9MpAmLFv/BVUjt+YD0HL9o2qg=; b=YXgbCwW6U0+G8TrtV35Fr6aHCJdg2W0iV/VxBzmOHTEHy2XLLL5jAwWtKiplKQvlmZny+d 2DsOKzOJbcFcgnF3D+lgNJUEyQSCyNLjtlQXy0XdkziFjgH8XVss1msVJDQVNHEVVVkwVL rK/Uc6AorEsTOA3ourl3e4aQXLb7/uM= Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap1.suse-dmz.suse.de (Postfix) with ESMTPS id 15710136B6; Sat, 31 Jul 2021 07:42:43 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap1.suse-dmz.suse.de with ESMTPSA id kE3AMfP+BGFPPQAAGKfGzw (envelope-from ); Sat, 31 Jul 2021 07:42:43 +0000 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: Chris Murphy Subject: [PATCH] btrfs-progs: mkfs: set super_cache_generation to 0 if we're using free space tree Date: Sat, 31 Jul 2021 15:42:40 +0800 Message-Id: <20210731074240.206263-1-wqu@suse.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org [HICCUP] There is a bug report that mkfs.btrfs -R free-space-tree still makes kernel to try to cleanup the v1 space cache: # mkfs.btrfs -R free-space-tree -f /dev/test/scratch1 # mount /dev/test/scratch1 /mnt/btrfs # dmesg | grep cleaning BTRFS info (device dm-6): cleaning free space cache v1 [CAUSE] By default, mkfs.btrfs will set super cache generation to (u64)-1, which will inform kernel that the v1 space cache is invalid, needs to regenerate it. But for free space cache tree, kernel will set super cache generation to 0, to indicate v1 space cache is not in use. This means, even we enabled free space tree with all the RO compatible bits and new tree, as long as super cache generation is not 0, kernel still consider the fs has some invalid v1 space cache, and will try to remove them. [FIX] This is not a big deal, but to make the "-R free-space-tree" to really work as kernel, we also need to set super cache generation to 0. Reported-by: Chris Murphy Link: https://lore.kernel.org/linux-btrfs/CAJCQCtSvgzyOnxtrqQZZirSycEHp+g0eDH5c+Kw9mW=PgxuXmw@mail.gmail.com/ Signed-off-by: Qu Wenruo Reviewed-by: Anand Jain Reviewed-by: Nikolay Borisov --- kernel-shared/free-space-tree.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel-shared/free-space-tree.c b/kernel-shared/free-space-tree.c index 2edc7fc716f5..7f589dfef950 100644 --- a/kernel-shared/free-space-tree.c +++ b/kernel-shared/free-space-tree.c @@ -1447,6 +1447,7 @@ int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info) btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE); btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); + btrfs_set_super_cache_generation(fs_info->super_copy, 0); ret = btrfs_commit_transaction(trans, tree_root); if (ret)