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 9308A7CBF for ; Wed, 22 May 2013 15:51:02 -0500 (CDT) Date: Wed, 22 May 2013 15:50:59 -0500 From: Ben Myers Subject: Re: [PATCH 06/11] xfs: fully initialise temp leaf in xfs_attr3_leaf_unbalance Message-ID: <20130522205059.GP20028@sgi.com> References: <1369123330-9579-1-git-send-email-david@fromorbit.com> <1369123330-9579-7-git-send-email-david@fromorbit.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1369123330-9579-7-git-send-email-david@fromorbit.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: Dave Chinner Cc: xfs@oss.sgi.com On Tue, May 21, 2013 at 06:02:05PM +1000, Dave Chinner wrote: > From: Dave Chinner > > xfs_attr3_leaf_unbalance() uses a temporary buffer for recombining > the entries in two leaves when the destination leaf requires > compaction. The temporary buffer ends up being copied back over the > original destination buffer, so the header in the temporary buffer > needs to contain all the information that is in the destination > buffer. > > To make sure the temporary buffer is fully initialised, once we've > set up the temporary incore header appropriately, write is back to > the temporary buffer before starting to move entries around. > > Signed-off-by: Dave Chinner > > --- > fs/xfs/xfs_attr_leaf.c | 16 +++++++++++++--- > 1 file changed, 13 insertions(+), 3 deletions(-) > > diff --git a/fs/xfs/xfs_attr_leaf.c b/fs/xfs/xfs_attr_leaf.c > index 0bce1b3..79ece72 100644 > --- a/fs/xfs/xfs_attr_leaf.c > +++ b/fs/xfs/xfs_attr_leaf.c > @@ -2181,14 +2181,24 @@ xfs_attr3_leaf_unbalance( > struct xfs_attr_leafblock *tmp_leaf; > struct xfs_attr3_icleaf_hdr tmphdr; > > - tmp_leaf = kmem_alloc(state->blocksize, KM_SLEEP); > - memset(tmp_leaf, 0, state->blocksize); > - memset(&tmphdr, 0, sizeof(tmphdr)); > + tmp_leaf = kmem_zalloc(state->blocksize, KM_SLEEP); > + > + /* > + * Copy the header into the temp leaf so that all the stuff > + * not in the incore header is present and gets copied back in > + * once we've moved all the entries. > + */ > + memcpy(tmp_leaf, save_leaf, xfs_attr3_leaf_hdr_size(save_leaf)); > > + memset(&tmphdr, 0, sizeof(tmphdr)); > tmphdr.magic = savehdr.magic; > tmphdr.forw = savehdr.forw; > tmphdr.back = savehdr.back; > tmphdr.firstused = state->blocksize; > + > + /* write the header to the temp buffer to initialise it */ > + xfs_attr3_leaf_hdr_to_disk(tmp_leaf, &tmphdr); > + Hrm. It seemed like the memset 0 for the incore temp header should have been enough for the purposes of moveents. Why did you have to add this additional hdr_to_disk? -Ben _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs