From patchwork Fri Oct 28 02:31:41 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 9400913 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D863760588 for ; Fri, 28 Oct 2016 02:33:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C8BD62A0E3 for ; Fri, 28 Oct 2016 02:33:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BDAAB2A130; Fri, 28 Oct 2016 02:33:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 36E9D2A0E3 for ; Fri, 28 Oct 2016 02:33:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034406AbcJ1CdH (ORCPT ); Thu, 27 Oct 2016 22:33:07 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:48358 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1034409AbcJ1CdG (ORCPT ); Thu, 27 Oct 2016 22:33:06 -0400 X-IronPort-AV: E=Sophos;i="5.20,367,1444665600"; d="scan'208";a="932118" Received: from unknown (HELO cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 28 Oct 2016 10:32:04 +0800 Received: from adam-work.localdomain (unknown [10.167.226.34]) by cn.fujitsu.com (Postfix) with ESMTP id 655F641B4BC4; Fri, 28 Oct 2016 10:32:03 +0800 (CST) From: Qu Wenruo To: linux-btrfs@vger.kernel.org, dsterba@suse.cz Subject: [PATCH 05/19] btrfs-progs: Introduce wrapper to recover raid56 data Date: Fri, 28 Oct 2016 10:31:41 +0800 Message-Id: <20161028023155.27336-6-quwenruo@cn.fujitsu.com> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20161028023155.27336-1-quwenruo@cn.fujitsu.com> References: <20161028023155.27336-1-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: 655F641B4BC4.AE025 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: quwenruo@cn.fujitsu.com Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Signed-off-by: Qu Wenruo --- raid56.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ raid56.h | 13 +++++++++++ 2 files changed, 89 insertions(+) diff --git a/raid56.c b/raid56.c index 3e471d6..8d54e55 100644 --- a/raid56.c +++ b/raid56.c @@ -269,3 +269,79 @@ int raid6_recov_datap(int nr_devs, size_t stripe_len, int dest1, void **data) } return 0; } + +int raid56_recov(int nr_devs, size_t stripe_len, u64 profile, int dest1, + int dest2, void **data) +{ + int min_devs; + int ret; + + if (profile & BTRFS_BLOCK_GROUP_RAID5) + min_devs = 2; + else if (profile & BTRFS_BLOCK_GROUP_RAID6) + min_devs = 3; + else + return -EINVAL; + if (nr_devs < min_devs) + return -EINVAL; + + /* Nothing to recover */ + if (dest1 == -1 && dest2 == -1) + return 0; + + /* Reorder dest1/2, so only dest2 can be -1 */ + if (dest1 == -1) { + dest1 = dest2; + dest2 = -1; + } else if (dest2 != -1 && dest1 != -1) { + /* Reorder dest1/2, ensure dest2 > dest1 */ + if (dest1 > dest2) { + int tmp; + + tmp = dest2; + dest2 = dest1; + dest1 = tmp; + } + } + + if (profile & BTRFS_BLOCK_GROUP_RAID5) { + if (dest2 != -1) + return 1; + return raid5_gen_result(nr_devs, stripe_len, dest1, data); + } + + /* RAID6 one dev corrupted case*/ + if (dest2 == -1) { + /* Regenerate P/Q */ + if (dest1 == nr_devs - 1 || dest1 == nr_devs - 2) { + raid6_gen_syndrome(nr_devs, stripe_len, data); + return 0; + } + + /* Regerneate data from P */ + return raid5_gen_result(nr_devs - 1, stripe_len, dest1, data); + } + + /* P/Q bot corrupted */ + if (dest1 == nr_devs - 2 && dest2 == nr_devs - 1) { + raid6_gen_syndrome(nr_devs, stripe_len, data); + return 0; + } + + /* 2 Data corrupted */ + if (dest2 < nr_devs - 2) + return raid6_recov_data2(nr_devs, stripe_len, dest1, dest2, + data); + /* Data and P*/ + if (dest2 == nr_devs - 1) + return raid6_recov_datap(nr_devs, stripe_len, dest1, data); + + /* + * Final case, Data and Q, recover data first then regenerate Q + */ + ret = raid5_gen_result(nr_devs - 1, stripe_len, dest1, data); + if (ret < 0) + return ret; + raid6_gen_syndrome(nr_devs, stripe_len, data); + return 0; +} diff --git a/raid56.h b/raid56.h index e30cc28..91d50c5 100644 --- a/raid56.h +++ b/raid56.h @@ -16,6 +16,8 @@ * Boston, MA 021110-1307, USA. */ +#include "kerncompat.h" + void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs); int raid5_gen_result(int nr_devs, size_t stripe_len, int dest, void **data); @@ -26,6 +28,17 @@ int raid6_recov_datap(int nr_devs, size_t stripe_len, int dest1, void **data); int raid6_recov_data2(int nr_devs, size_t stripe_len, int dest1, int dest2, void **data); +/* + * Recover raid56 data + * @dest1/2 can be -1 to indicate non-corrupted case + * + * Return >0 for unrecoverable case. + * Return 0 for recoverable case. And recovered data will be stored into @data + * Return <0 for fatal error + */ +int raid56_recov(int nr_devs, size_t stripe_len, u64 profile, int dest1, + int dest2, void **data); + /* Galois field tables */ extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256))); extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256)));