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 145A27F3F for ; Mon, 18 Mar 2013 18:17:01 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay3.corp.sgi.com (Postfix) with ESMTP id A1A71AC002 for ; Mon, 18 Mar 2013 16:17:00 -0700 (PDT) Received: from ipmail05.adl6.internode.on.net (ipmail05.adl6.internode.on.net [150.101.137.143]) by cuda.sgi.com with ESMTP id ovrQzbPSzY2ALDgO for ; Mon, 18 Mar 2013 16:16:58 -0700 (PDT) Date: Tue, 19 Mar 2013 10:16:57 +1100 From: Dave Chinner Subject: Re: [PATCH] xfsprogs: reduce bb_numrecs in bno/cnt btrees when log consumes all agf space Message-ID: <20130318231657.GR6369@dastard> References: <1363642689-17718-1-git-send-email-bfoster@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1363642689-17718-1-git-send-email-bfoster@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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: Brian Foster Cc: xfs@oss.sgi.com On Mon, Mar 18, 2013 at 05:38:09PM -0400, Brian Foster wrote: > The mkfs code currently creates a single free space extent record > for each of the bno and cnt btrees in each AG. The start block of > the record is pushed forward on the AG that hosts an internal log. > If the log happens to consume all available space in the AG, the > start block becomes equal to sb->sb_agblocks and thus invalid. > This causes xfs_repair to complain. > > For example, the following sequence: > > mkfs.xfs -d file,name=./fs.img,size=50g,agsize=16m > xfs_repair ./fs.img > > ... produces the following xfs_repair output: > > Phase 1 - find and verify superblock... > Phase 2 - using internal log > - scan filesystem freespace and inode maps... > invalid start block 4096 in record 0 of bno btree block 1600/1 > invalid start block 4096 in record 0 of cnt btree block 1600/2 > - found root inode chunk > ... > > xfs_repair appears to correct the numrecs value such that subsequent > checks are successful. The sequence above is pulled from xfstests > > Modify mkfs.xfs such that we check the block count value of the > free space record for the log AG after the log is accounted for. If > no space is left for the record, reset the record count to 0. > > Signed-off-by: Brian Foster > --- > mkfs/xfs_mkfs.c | 6 ++++++ > 1 files changed, 6 insertions(+), 0 deletions(-) > > diff --git a/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c > index c84448e..c4ae15b 100644 > --- a/mkfs/xfs_mkfs.c > +++ b/mkfs/xfs_mkfs.c > @@ -2594,6 +2594,9 @@ an AG size that is one stripe unit smaller, for example %llu.\n"), > } > arec->ar_blockcount = cpu_to_be32(agsize - > be32_to_cpu(arec->ar_startblock)); > + if (!arec->ar_blockcount) > + block->bb_numrecs = cpu_to_be16(0); You don't need to endian swap zero. block->bb_numrecs = 0; is just fine. I'd also add a comment to explain why this is being done.... Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs