Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932206AbWATVSI (ORCPT ); Fri, 20 Jan 2006 16:18:08 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932208AbWATVSI (ORCPT ); Fri, 20 Jan 2006 16:18:08 -0500 Received: from mx1.redhat.com ([66.187.233.31]:55776 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S932206AbWATVSH (ORCPT ); Fri, 20 Jan 2006 16:18:07 -0500 Date: Fri, 20 Jan 2006 21:17:59 +0000 From: Alasdair G Kergon To: Andrew Morton Cc: linux-kernel@vger.kernel.org Subject: [PATCH 6/9] device-mapper snapshot: barriers not supported Message-ID: <20060120211759.GG4724@agk.surrey.redhat.com> Mail-Followup-To: Alasdair G Kergon , Andrew Morton , linux-kernel@vger.kernel.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1174 Lines: 34 The snapshot and origin targets are incapable of handling barriers and need to indicate this. Signed-Off-By: Alasdair G Kergon Index: linux-2.6.16-rc1/drivers/md/dm-snap.c =================================================================== --- linux-2.6.16-rc1.orig/drivers/md/dm-snap.c +++ linux-2.6.16-rc1/drivers/md/dm-snap.c @@ -792,6 +792,9 @@ static int snapshot_map(struct dm_target if (!s->valid) return -EIO; + if (unlikely(bio_barrier(bio))) + return -EOPNOTSUPP; + /* * Write to snapshot - higher level takes care of RW/RO * flags so we should only get this if we are @@ -1058,6 +1061,9 @@ 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) : 1; } - 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/