From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q9C5iau7072493 for ; Fri, 12 Oct 2012 00:44:37 -0500 Received: from ipmail05.adl6.internode.on.net (ipmail05.adl6.internode.on.net [150.101.137.143]) by cuda.sgi.com with ESMTP id 2PmZns3SrFzeQW97 for ; Thu, 11 Oct 2012 22:46:08 -0700 (PDT) Received: from disappointment ([192.168.1.1]) by dastard with esmtp (Exim 4.76) (envelope-from ) id 1TMY3I-0003aJ-7T for xfs@oss.sgi.com; Fri, 12 Oct 2012 16:44:52 +1100 Received: from dave by disappointment with local (Exim 4.80) (envelope-from ) id 1TMY38-00057A-4G for xfs@oss.sgi.com; Fri, 12 Oct 2012 16:44:42 +1100 From: Dave Chinner Subject: [PATCH 21/23] xfs: add buffer pre-write callback Date: Fri, 12 Oct 2012 16:44:27 +1100 Message-Id: <1350020669-19504-22-git-send-email-david@fromorbit.com> In-Reply-To: <1350020669-19504-1-git-send-email-david@fromorbit.com> References: <1350020669-19504-1-git-send-email-david@fromorbit.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 Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com From: Dave Chinner Add a callback to the buffer write path to enable verification of the buffer and CRC calculation prior to issuing the write to the underlying storage. If the callback function detects some kind of failure or error condition, it must mark the buffer with an error so that the caller can take appropriate action. In the case of xfs_buf_ioapply(), a corrupt metadta buffer willt rigger a shutdown of the filesystem, because something is clearly wrong and we can't allow corrupt metadata to be written to disk. Signed-off-by: Dave Chinner --- fs/xfs/xfs_buf.c | 16 ++++++++++++++++ fs/xfs/xfs_buf.h | 3 +++ 2 files changed, 19 insertions(+) diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 62b7e89..c073236 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -569,7 +569,9 @@ found: */ if (bp->b_flags & XBF_STALE) { ASSERT((bp->b_flags & _XBF_DELWRI_Q) == 0); + ASSERT(bp->b_iodone == NULL); bp->b_flags &= _XBF_KMEM | _XBF_PAGES; + bp->b_pre_io = NULL; } trace_xfs_buf_find(bp, flags, _RET_IP_); @@ -1314,6 +1316,20 @@ _xfs_buf_ioapply( rw |= REQ_META; /* + * run the pre-io callback function if it exists. If this function + * fails it will mark the buffer with an error and the IO should + * not be dispatched. + */ + if (bp->b_pre_io) { + bp->b_pre_io(bp); + if (bp->b_error) { + xfs_force_shutdown(bp->b_target->bt_mount, + SHUTDOWN_CORRUPT_INCORE); + return; + } + } + + /* * Walk all the vectors issuing IO on them. Set up the initial offset * into the buffer and the desired IO size before we start - * _xfs_buf_ioapply_vec() will modify them appropriately for each diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h index 677b1dc..51bc16a 100644 --- a/fs/xfs/xfs_buf.h +++ b/fs/xfs/xfs_buf.h @@ -155,6 +155,9 @@ typedef struct xfs_buf { unsigned int b_offset; /* page offset in first page */ unsigned short b_error; /* error code on I/O */ + void (*b_pre_io)(struct xfs_buf *); + /* pre-io callback function */ + #ifdef XFS_BUF_LOCK_TRACKING int b_last_holder; #endif -- 1.7.10 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs