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 B61D329E10 for ; Mon, 27 May 2013 01:38:55 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay1.corp.sgi.com (Postfix) with ESMTP id 93B598F8033 for ; Sun, 26 May 2013 23:38:55 -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 toZaMzCtptrILUoX for ; Sun, 26 May 2013 23:38:54 -0700 (PDT) Received: from disappointment ([192.168.1.1]) by dastard with esmtp (Exim 4.76) (envelope-from ) id 1Ugr4p-0008Fn-Sr for xfs@oss.sgi.com; Mon, 27 May 2013 16:38:39 +1000 Received: from dave by disappointment with local (Exim 4.80) (envelope-from ) id 1Ugr4p-0003xP-PE for xfs@oss.sgi.com; Mon, 27 May 2013 16:38:39 +1000 From: Dave Chinner Subject: [PATCH 6/9] xfs: disable swap extents ioctl on CRC enabled filesystems Date: Mon, 27 May 2013 16:38:24 +1000 Message-Id: <1369636707-15150-7-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 Currently, swapping extents from one inode to another is a simple act of switching data and attribute forks from one inode to another. This, unfortunately in no longer so simple with CRC enabled filesystems as there is owner information embedded into the BMBT blocks that are swapped between inodes. Hence swapping the forks between inodes results in the inodes having mapping blocks that point to the wrong owner and hence are considered corrupt. To fix this we need an extent tree block or record based swap algorithm so that the BMBT block owner information can be updated atomically in the swap transaction. This is a significant piece of new work, so for the moment simply don't allow swap extent operations to succeed on CRC enabled filesystems. Signed-off-by: Dave Chinner --- fs/xfs/xfs_dfrag.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/xfs/xfs_dfrag.c b/fs/xfs/xfs_dfrag.c index f852b08..c407e1c 100644 --- a/fs/xfs/xfs_dfrag.c +++ b/fs/xfs/xfs_dfrag.c @@ -219,6 +219,14 @@ xfs_swap_extents( int taforkblks = 0; __uint64_t tmp; + /* + * We have no way of updating owner information in the BMBT blocks for + * each inode on CRC enabled filesystems, so to avoid corrupting the + * this metadata we simply don't allow extent swaps to occur. + */ + if (xfs_sb_version_hascrc(&mp->m_sb)) + return XFS_ERROR(EINVAL); + tempifp = kmem_alloc(sizeof(xfs_ifork_t), KM_MAYFAIL); if (!tempifp) { error = XFS_ERROR(ENOMEM); -- 1.7.10.4 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs