Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965995AbXHGV0G (ORCPT ); Tue, 7 Aug 2007 17:26:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935729AbXHGU4r (ORCPT ); Tue, 7 Aug 2007 16:56:47 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:59927 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935554AbXHGU4p (ORCPT ); Tue, 7 Aug 2007 16:56:45 -0400 Date: Tue, 7 Aug 2007 13:49:10 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, Linus Torvalds Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Stefan Bader , Alasdair G Kergon Subject: [2.6.22.2 review 73/84] dm: disable barriers Message-ID: <20070807204910.GW23028@kroah.com> References: <20070807204034.882009319@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="dm-disable-barriers.patch" In-Reply-To: <20070807204157.GA23028@kroah.com> User-Agent: Mutt/1.5.15 (2007-04-06) X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2756 Lines: 91 From: Stefan Bader This patch causes device-mapper to reject any barrier requests. This is done since most of the targets won't handle this correctly anyway. So until the situation improves it is better to reject these requests at the first place. Since barrier requests won't get to the targets, the checks there can be removed. Signed-off-by: Stefan Bader Signed-off-by: Alasdair G Kergon Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-crypt.c | 3 --- drivers/md/dm-mpath.c | 3 --- drivers/md/dm-snap.c | 6 ------ drivers/md/dm.c | 9 +++++++++ 4 files changed, 9 insertions(+), 12 deletions(-) --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -943,9 +943,6 @@ static int crypt_map(struct dm_target *t struct crypt_config *cc = ti->private; struct crypt_io *io; - if (bio_barrier(bio)) - return -EOPNOTSUPP; - io = mempool_alloc(cc->io_pool, GFP_NOIO); io->target = ti; io->base_bio = bio; --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -798,9 +798,6 @@ static int multipath_map(struct dm_targe struct mpath_io *mpio; struct multipath *m = (struct multipath *) ti->private; - if (bio_barrier(bio)) - return -EOPNOTSUPP; - mpio = mempool_alloc(m->mpio_pool, GFP_NOIO); dm_bio_record(&mpio->details, bio); --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -887,9 +887,6 @@ static int snapshot_map(struct dm_target if (!s->valid) return -EIO; - if (unlikely(bio_barrier(bio))) - return -EOPNOTSUPP; - /* FIXME: should only take write lock if we need * to copy an exception */ down_write(&s->lock); @@ -1160,9 +1157,6 @@ static int origin_map(struct dm_target * struct dm_dev *dev = (struct dm_dev *) ti->private; bio->bi_bdev = dev->bdev; - if (unlikely(bio_barrier(bio))) - return -EOPNOTSUPP; - /* Only tell snapshots if this is a write */ return (bio_rw(bio) == WRITE) ? do_origin(dev, bio) : DM_MAPIO_REMAPPED; } --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -802,6 +802,15 @@ static int dm_request(request_queue_t *q int rw = bio_data_dir(bio); struct mapped_device *md = q->queuedata; + /* + * There is no use in forwarding any barrier request since we can't + * guarantee it is (or can be) handled by the targets correctly. + */ + if (unlikely(bio_barrier(bio))) { + bio_endio(bio, bio->bi_size, -EOPNOTSUPP); + return 0; + } + down_read(&md->io_lock); disk_stat_inc(dm_disk(md), ios[rw]); -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/