From: Alasdair G Kergon <agk@redhat.com>

Set the target's split_io field when building a dm-mirror device so
incoming bios won't span the mirror's internal regions.  Without this,
regions can be accessed while not holding correct locks and data corruption
is possible.

Reported-By: "Zhao Qian" <zhaoqian@aaastor.com>
From: Kevin Corry <kevcorry@us.ibm.com>
Signed-Off-By: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 drivers/md/dm-raid1.c |    1 +
 1 files changed, 1 insertion(+)

diff -puN drivers/md/dm-raid1.c~device-mapper-dm-raid1-limit-bios-to-size-of-mirror-region drivers/md/dm-raid1.c
--- devel/drivers/md/dm-raid1.c~device-mapper-dm-raid1-limit-bios-to-size-of-mirror-region	2005-06-30 22:25:16.000000000 -0700
+++ devel-akpm/drivers/md/dm-raid1.c	2005-06-30 22:25:16.000000000 -0700
@@ -1060,6 +1060,7 @@ static int mirror_ctr(struct dm_target *
 	}
 
 	ti->private = ms;
+ 	ti->split_io = ms->rh->region_size;
 
 	r = kcopyd_client_create(DM_IO_PAGES, &ms->kcopyd_client);
 	if (r) {
_