From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id C95B97F6D for ; Thu, 12 Nov 2015 09:37:32 -0600 (CST) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay3.corp.sgi.com (Postfix) with ESMTP id 3B1DAAC002 for ; Thu, 12 Nov 2015 07:37:32 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id g8gADF2Cji2gpcf2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Thu, 12 Nov 2015 07:37:30 -0800 (PST) Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id D24ACC60EE for ; Thu, 12 Nov 2015 15:37:29 +0000 (UTC) Received: from bfoster.bfoster (dhcp-41-36.bos.redhat.com [10.18.41.36]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tACFbTri032681 for ; Thu, 12 Nov 2015 10:37:29 -0500 From: Brian Foster Subject: [PATCH v2 5/8] xfs: support a crc verification only log record pass Date: Thu, 12 Nov 2015 10:37:25 -0500 Message-Id: <1447342648-40012-6-git-send-email-bfoster@redhat.com> In-Reply-To: <1447342648-40012-1-git-send-email-bfoster@redhat.com> References: <1447342648-40012-1-git-send-email-bfoster@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com Log recovery torn write detection uses CRC verification over a range of the active log to identify torn writes. Since the generic log recovery pass code implements a superset of the functionality required for CRC verification, it can be easily modified to support a CRC verification only pass. Create a new CRC pass type and update the log record processing helper to skip everything beyond CRC verification when in this mode. This pass will be invoked in subsequent patches to implement torn write detection. Signed-off-by: Brian Foster --- fs/xfs/libxfs/xfs_log_recover.h | 1 + fs/xfs/xfs_log_recover.c | 24 +++++++++++++++++++----- 2 files changed, 20 insertions(+), 5 deletions(-) diff --git a/fs/xfs/libxfs/xfs_log_recover.h b/fs/xfs/libxfs/xfs_log_recover.h index 1c55ccb..8e385f9 100644 --- a/fs/xfs/libxfs/xfs_log_recover.h +++ b/fs/xfs/libxfs/xfs_log_recover.h @@ -60,6 +60,7 @@ typedef struct xlog_recover { */ #define XLOG_BC_TABLE_SIZE 64 +#define XLOG_RECOVER_CRCPASS 0 #define XLOG_RECOVER_PASS1 1 #define XLOG_RECOVER_PASS2 2 diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index e0318e8..1be2590 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -4159,13 +4159,27 @@ xlog_recover_process( int error; __le32 crc; + crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len)); + /* - * Check the CRC and issue a warning if and only if the CRC in the - * header is non-zero. This is an advisory warning and the zero CRC - * check prevents warnings from being emitted when upgrading the kernel - * from one that does not add CRCs by default. + * Nothing else to do if this is a CRC verification pass. Just return + * if this a record with a non-zero crc. Unfortunately, mkfs always + * sets h_crc to 0 so we must consider this valid even on v5 supers. + * Otherwise, return EFSBADCRC on failure so the callers up the stack + * know precisely what failed. + */ + if (pass == XLOG_RECOVER_CRCPASS) { + if (rhead->h_crc && crc != le32_to_cpu(rhead->h_crc)) + return -EFSBADCRC; + return 0; + } + + /* + * We're in the normal recovery path. Issue a warning if and only if the + * CRC in the header is non-zero. This is an advisory warning and the + * zero CRC check prevents warnings from being emitted when upgrading + * the kernel from one that does not add CRCs by default. */ - crc = xlog_cksum(log, rhead, dp, be32_to_cpu(rhead->h_len)); if (crc != le32_to_cpu(rhead->h_crc)) { if (rhead->h_crc || xfs_sb_version_hascrc(&log->l_mp->m_sb)) { xfs_alert(log->l_mp, -- 2.1.0 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs