From patchwork Thu May 25 06:21:49 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 9747755 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 DC4E76032C for ; Thu, 25 May 2017 06:22:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DD072274D0 for ; Thu, 25 May 2017 06:22:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CF81227D4A; Thu, 25 May 2017 06:22:33 +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 48AFE274D0 for ; Thu, 25 May 2017 06:22:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1165144AbdEYGWa (ORCPT ); Thu, 25 May 2017 02:22:30 -0400 Received: from cn.fujitsu.com ([59.151.112.132]:45979 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1031086AbdEYGW2 (ORCPT ); Thu, 25 May 2017 02:22:28 -0400 X-IronPort-AV: E=Sophos;i="5.22,518,1449504000"; d="scan'208";a="19288945" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 25 May 2017 14:22:24 +0800 Received: from G08CNEXCHPEKD02.g08.fujitsu.local (unknown [10.167.33.83]) by cn.fujitsu.com (Postfix) with ESMTP id 3E08F47C6555; Thu, 25 May 2017 14:22:23 +0800 (CST) Received: from localhost.localdomain (10.167.226.34) by G08CNEXCHPEKD02.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.319.2; Thu, 25 May 2017 14:22:22 +0800 From: Qu Wenruo To: CC: , Subject: [PATCH v4 04/20] btrfs-progs: raid56: Allow raid6 to recover data and p Date: Thu, 25 May 2017 14:21:49 +0800 Message-ID: <20170525062205.11660-5-quwenruo@cn.fujitsu.com> X-Mailer: git-send-email 2.13.0 In-Reply-To: <20170525062205.11660-1-quwenruo@cn.fujitsu.com> References: <20170525062205.11660-1-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 X-Originating-IP: [10.167.226.34] X-yoursite-MailScanner-ID: 3E08F47C6555.AD80E 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 Copied from kernel lib/raid6/recov.c. Minor modifications includes: - Rename from raid6_datap_recov_intx() to raid5_recov_datap() - Rename parameter from faila to dest1 Signed-off-by: Qu Wenruo --- kernel-lib/raid56.c | 41 +++++++++++++++++++++++++++++++++++++++++ kernel-lib/raid56.h | 2 ++ 2 files changed, 43 insertions(+) diff --git a/kernel-lib/raid56.c b/kernel-lib/raid56.c index dca8f8d4..e078972b 100644 --- a/kernel-lib/raid56.c +++ b/kernel-lib/raid56.c @@ -239,3 +239,44 @@ int raid6_recov_data2(int nr_devs, size_t stripe_len, int dest1, int dest2, free(zero_mem2); return ret; } + +/* + * Raid 6 recover code copied from kernel lib/raid6/recov.c + * - rename from raid6_datap_recov_intx1() + * - parameter changed from faila to dest1 + */ +int raid6_recov_datap(int nr_devs, size_t stripe_len, int dest1, void **data) +{ + u8 *p, *q, *dq; + const u8 *qmul; /* Q multiplier table */ + char *zero_mem; + + p = (u8 *)data[nr_devs - 2]; + q = (u8 *)data[nr_devs - 1]; + + zero_mem = calloc(1, stripe_len); + if (!zero_mem) + return -ENOMEM; + + /* Compute syndrome with zero for the missing data page + Use the dead data page as temporary storage for delta q */ + dq = (u8 *)data[dest1]; + data[dest1] = (void *)zero_mem; + data[nr_devs - 1] = dq; + + raid6_gen_syndrome(nr_devs, stripe_len, data); + + /* Restore pointer table */ + data[dest1] = dq; + data[nr_devs - 1] = q; + + /* Now, pick the proper data tables */ + qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[dest1]]]; + + /* Now do it... */ + while ( stripe_len-- ) { + *p++ ^= *dq = qmul[*q ^ *dq]; + q++; dq++; + } + return 0; +} diff --git a/kernel-lib/raid56.h b/kernel-lib/raid56.h index 8d64256f..83ac39a1 100644 --- a/kernel-lib/raid56.h +++ b/kernel-lib/raid56.h @@ -42,4 +42,6 @@ extern const u8 raid6_gfexi[256] __attribute__((aligned(256))); /* Recover raid6 with 2 data corrupted */ int raid6_recov_data2(int nr_devs, size_t stripe_len, int dest1, int dest2, void **data); +/* Recover data and P */ +int raid6_recov_datap(int nr_devs, size_t stripe_len, int dest1, void **data); #endif