From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id DB9FA29DF8 for ; Mon, 27 May 2013 01:38:45 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay2.corp.sgi.com (Postfix) with ESMTP id A79D1304039 for ; Sun, 26 May 2013 23:38:45 -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 z6XUrdXtA4kDwo09 for ; Sun, 26 May 2013 23:38:43 -0700 (PDT) Received: from disappointment ([192.168.1.1]) by dastard with esmtp (Exim 4.76) (envelope-from ) id 1Ugr4f-0008FX-O7 for xfs@oss.sgi.com; Mon, 27 May 2013 16:38:29 +1000 Received: from dave by disappointment with local (Exim 4.80) (envelope-from ) id 1Ugr4f-0003x7-Kt for xfs@oss.sgi.com; Mon, 27 May 2013 16:38:29 +1000 From: Dave Chinner Subject: [PATCH 2/9] xfs: fix incorrect remote symlink block count Date: Mon, 27 May 2013 16:38:20 +1000 Message-Id: <1369636707-15150-3-git-send-email-david@fromorbit.com> In-Reply-To: <1369636707-15150-1-git-send-email-david@fromorbit.com> References: <1369636707-15150-1-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 CRCs are enabled, the number of blocks needed to hold a remote symlink on a 1k block size filesystem may be 2 instead of 1. The transaction reservation for the allocated bloks was not taking this into account and only allocating one block. hence when trying to read or invalidate such symlinks, we are mapping a hole where there should be a block and things go bad at that point. Fix the reservation to use the correct block count, clean up the block count calculation similar to the remote attribute calculation, and add a debug guard to detect when we don't write the entire symlink to disk. Signed-off-by: Dave Chinner --- fs/xfs/xfs_symlink.c | 20 ++++++-------------- 1 file changed, 6 insertions(+), 14 deletions(-) diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c index 5f234389..195a403 100644 --- a/fs/xfs/xfs_symlink.c +++ b/fs/xfs/xfs_symlink.c @@ -56,16 +56,9 @@ xfs_symlink_blocks( struct xfs_mount *mp, int pathlen) { - int fsblocks = 0; - int len = pathlen; + int buflen = XFS_SYMLINK_BUF_SPACE(mp, mp->m_sb.sb_blocksize); - do { - fsblocks++; - len -= XFS_SYMLINK_BUF_SPACE(mp, mp->m_sb.sb_blocksize); - } while (len > 0); - - ASSERT(fsblocks <= XFS_SYMLINK_MAPS); - return fsblocks; + return (pathlen + buflen - 1) / buflen; } static int @@ -405,7 +398,7 @@ xfs_symlink( if (pathlen <= XFS_LITINO(mp, dp->i_d.di_version)) fs_blocks = 0; else - fs_blocks = XFS_B_TO_FSB(mp, pathlen); + fs_blocks = xfs_symlink_blocks(mp, pathlen); resblks = XFS_SYMLINK_SPACE_RES(mp, link_name->len, fs_blocks); error = xfs_trans_reserve(tp, resblks, XFS_SYMLINK_LOG_RES(mp), 0, XFS_TRANS_PERM_LOG_RES, XFS_SYMLINK_LOG_COUNT); @@ -512,7 +505,7 @@ xfs_symlink( cur_chunk = target_path; offset = 0; for (n = 0; n < nmaps; n++) { - char *buf; + char *buf; d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock); byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount); @@ -525,9 +518,7 @@ xfs_symlink( bp->b_ops = &xfs_symlink_buf_ops; byte_cnt = XFS_SYMLINK_BUF_SPACE(mp, byte_cnt); - if (pathlen < byte_cnt) { - byte_cnt = pathlen; - } + byte_cnt = min(byte_cnt, pathlen); buf = bp->b_addr; buf += xfs_symlink_hdr_set(mp, ip->i_ino, offset, @@ -542,6 +533,7 @@ xfs_symlink( xfs_trans_log_buf(tp, bp, 0, (buf + byte_cnt - 1) - (char *)bp->b_addr); } + ASSERT(pathlen == 0); } /* -- 1.7.10.4 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs