From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id 2D5FB29E06 for ; Sun, 19 May 2013 18:51:45 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay1.corp.sgi.com (Postfix) with ESMTP id DAF648F8033 for ; Sun, 19 May 2013 16:51:44 -0700 (PDT) Received: from ipmail07.adl2.internode.on.net (ipmail07.adl2.internode.on.net [150.101.137.131]) by cuda.sgi.com with ESMTP id lqzddEBojFoXinE4 for ; Sun, 19 May 2013 16:51:43 -0700 (PDT) Received: from disappointment ([192.168.1.1]) by dastard with esmtp (Exim 4.76) (envelope-from ) id 1UeDO2-00069x-TA for xfs@oss.sgi.com; Mon, 20 May 2013 09:51:34 +1000 Received: from dave by disappointment with local (Exim 4.80) (envelope-from ) id 1UeDO2-0003z3-Qb for xfs@oss.sgi.com; Mon, 20 May 2013 09:51:34 +1000 From: Dave Chinner Subject: [PATCH 11/14] xfs: remote attribute tail zeroing does too much Date: Mon, 20 May 2013 09:51:18 +1000 Message-Id: <1369007481-15185-12-git-send-email-david@fromorbit.com> In-Reply-To: <1369007481-15185-1-git-send-email-david@fromorbit.com> References: <1369007481-15185-1-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 Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com From: Dave Chinner When an attribute data does not fill then entire remote block, we zero the remaining part of the buffer. This, however, needs to take into account that the buffer has a header, and so the offset where zeroing starts and the length of zeroing need to take this into account. Otherwise we end up with zeros over the end of the attribute value when CRCs are enabled. While there, make sure we only ask to map an extent that covers the remaining range of the attribute, rather than asking every time for the full length of remote data. If the remote attribute blocks are contiguous with other parts of the attribute tree, it will map those blocks as well and we can potentially zero them incorrectly. We can also get buffer size mistmatches when trying to read or remove the remote attribute, and this can lead to not finding the correct buffer when looking it up in cache. Signed-off-by: Dave Chinner --- fs/xfs/xfs_attr_remote.c | 37 ++++++++++++++++++------------------- 1 file changed, 18 insertions(+), 19 deletions(-) diff --git a/fs/xfs/xfs_attr_remote.c b/fs/xfs/xfs_attr_remote.c index bcdc07c..e207bf0 100644 --- a/fs/xfs/xfs_attr_remote.c +++ b/fs/xfs/xfs_attr_remote.c @@ -296,10 +296,7 @@ xfs_attr_rmtval_set( * and we may not need that many, so we have to handle this when * allocating the blocks below. */ - if (!crcs) - blkcnt = XFS_B_TO_FSB(mp, args->valuelen); - else - blkcnt = xfs_attr3_rmt_blocks(mp, args->valuelen); + blkcnt = xfs_attr3_rmt_blocks(mp, args->valuelen); error = xfs_bmap_first_unused(args->trans, args->dp, blkcnt, &lfileoff, XFS_ATTR_FORK); @@ -394,8 +391,11 @@ xfs_attr_rmtval_set( */ lblkno = args->rmtblkno; valuelen = args->valuelen; + blkcnt = args->rmtblkcnt; while (valuelen > 0) { int byte_cnt; + int hdr_size; + int dblkcnt; char *buf; /* @@ -404,7 +404,7 @@ xfs_attr_rmtval_set( xfs_bmap_init(args->flist, args->firstblock); nmap = 1; error = xfs_bmapi_read(dp, (xfs_fileoff_t)lblkno, - args->rmtblkcnt, &map, &nmap, + blkcnt, &map, &nmap, XFS_BMAPI_ATTRFORK); if (error) return(error); @@ -413,26 +413,25 @@ xfs_attr_rmtval_set( (map.br_startblock != HOLESTARTBLOCK)); dblkno = XFS_FSB_TO_DADDR(mp, map.br_startblock), - blkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount); + dblkcnt = XFS_FSB_TO_BB(mp, map.br_blockcount); - bp = xfs_buf_get(mp->m_ddev_targp, dblkno, blkcnt, 0); + bp = xfs_buf_get(mp->m_ddev_targp, dblkno, dblkcnt, 0); if (!bp) return ENOMEM; bp->b_ops = &xfs_attr3_rmt_buf_ops; - - byte_cnt = BBTOB(bp->b_length); - byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, byte_cnt); - if (valuelen < byte_cnt) - byte_cnt = valuelen; - buf = bp->b_addr; - buf += xfs_attr3_rmt_hdr_set(mp, dp->i_ino, offset, + + byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, BBTOB(bp->b_length)); + byte_cnt = min_t(int, valuelen, byte_cnt); + hdr_size = xfs_attr3_rmt_hdr_set(mp, dp->i_ino, offset, byte_cnt, bp); - memcpy(buf, src, byte_cnt); + ASSERT(hdr_size + byte_cnt <= BBTOB(bp->b_length)); - if (byte_cnt < BBTOB(bp->b_length)) - xfs_buf_zero(bp, byte_cnt, - BBTOB(bp->b_length) - byte_cnt); + memcpy(buf + hdr_size, src, byte_cnt); + + if (byte_cnt + hdr_size < BBTOB(bp->b_length)) + xfs_buf_zero(bp, byte_cnt + hdr_size, + BBTOB(bp->b_length) - byte_cnt - hdr_size); error = xfs_bwrite(bp); /* GROT: NOTE: synchronous write */ xfs_buf_relse(bp); @@ -442,9 +441,9 @@ xfs_attr_rmtval_set( src += byte_cnt; valuelen -= byte_cnt; offset += byte_cnt; - hdrcnt--; lblkno += map.br_blockcount; + blkcnt -= map.br_blockcount; } ASSERT(valuelen == 0); return 0; -- 1.7.10.4 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs