From patchwork Wed Nov 26 02:43:41 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gui Hecheng X-Patchwork-Id: 5383711 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 9620AC11AD for ; Wed, 26 Nov 2014 02:45:31 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id AA9CB20160 for ; Wed, 26 Nov 2014 02:45:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C3180201CD for ; Wed, 26 Nov 2014 02:45:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752017AbaKZCp1 (ORCPT ); Tue, 25 Nov 2014 21:45:27 -0500 Received: from cn.fujitsu.com ([59.151.112.132]:51513 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751149AbaKZCpZ (ORCPT ); Tue, 25 Nov 2014 21:45:25 -0500 X-IronPort-AV: E=Sophos;i="5.04,848,1406563200"; d="scan'208";a="43992800" Received: from unknown (HELO edo.cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 26 Nov 2014 10:42:09 +0800 Received: from G08CNEXCHPEKD02.g08.fujitsu.local (localhost.localdomain [127.0.0.1]) by edo.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id sAQ2j7kC012896 for ; Wed, 26 Nov 2014 10:45:07 +0800 Received: from localhost.localdomain (10.167.226.111) by G08CNEXCHPEKD02.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.181.6; Wed, 26 Nov 2014 10:45:29 +0800 From: Gui Hecheng To: CC: Gui Hecheng Subject: [PATCH 2/2] btrfs-progs: convert: fix unable to rollback case with removed empty block groups Date: Wed, 26 Nov 2014 10:43:41 +0800 Message-ID: <1416969821-2729-2-git-send-email-guihc.fnst@cn.fujitsu.com> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1416969821-2729-1-git-send-email-guihc.fnst@cn.fujitsu.com> References: <1416969821-2729-1-git-send-email-guihc.fnst@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.111] Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Run fstests: btrfs/012 will fail with message: unable to do rollback It is because the rollback function checks sequentially each piece of space to map to a certain block group. If some piece doesn't, rollback refuses to continue. After kernel commit: commit 47ab2a6c689913db23ccae38349714edf8365e0a Btrfs: remove empty block groups automatically Empty block groups are removed, so there are possible gaps: |--block group 1--| |--block group 2--| ^ | gap So the piece of space of the gap belongs to a removed empty block group, and rollback should detect this case, and feel free to continue. Signed-off-by: Gui Hecheng --- btrfs-convert.c | 13 +++++++++++-- volumes.c | 2 ++ 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/btrfs-convert.c b/btrfs-convert.c index a544fc6..504c7b3 100644 --- a/btrfs-convert.c +++ b/btrfs-convert.c @@ -2368,8 +2368,17 @@ static int may_rollback(struct btrfs_root *root) while (1) { ret = btrfs_map_block(&info->mapping_tree, WRITE, bytenr, &length, &multi, 0, NULL); - if (ret) + if (ret) { + if (ret == -ENOENT) { + /* removed block group at the tail */ + if (length == (u64)-1) + break; + + /* removed block group in the middle */ + goto next; + } goto fail; + } num_stripes = multi->num_stripes; physical = multi->stripes[0].physical; @@ -2377,7 +2386,7 @@ static int may_rollback(struct btrfs_root *root) if (num_stripes != 1 || physical != bytenr) goto fail; - +next: bytenr += length; if (bytenr >= total_bytes) break; diff --git a/volumes.c b/volumes.c index a1fd162..a988cdb 100644 --- a/volumes.c +++ b/volumes.c @@ -1318,10 +1318,12 @@ again: ce = search_cache_extent(&map_tree->cache_tree, logical); if (!ce) { kfree(multi); + *length = (u64)-1; return -ENOENT; } if (ce->start > logical) { kfree(multi); + *length = ce->start - logical; return -ENOENT; }