On Wed, May 01 2013 at 2:58am -0400, Bharata B Rao <bharata.rao@xxxxxxxxx> wrote: > On Tue, Apr 30, 2013 at 10:02 PM, Mike Snitzer <snitzer@xxxxxxxxxx> wrote: > > On Tue, Apr 30 2013 at 12:07am -0400, > > Bharata B Rao <bharata.rao@xxxxxxxxx> wrote: > > > >> > >> # lsblk > >> NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT > >> sda 8:0 0 50G 0 disk > >> └─mpathb (dm-12) 252:12 0 50G 0 mpath > >> └─ws_vg-lvol0 (dm-11) 252:11 0 1G 0 lvm > >> sde 8:64 0 50G 0 disk > >> └─mpathb (dm-12) 252:12 0 50G 0 mpath > >> └─ws_vg-lvol0 (dm-11) 252:11 0 1G 0 lvm > >> > > > > > > Anyway, this patch fixes things for me: > > Thanks, this fixes the issue for me too. However if LV/VG/PV are > created on multipath device, then WRITE SAME still doesn't get > advertised for the LV. I had to disable multipath and re-create > LV/VG/PV on a normal device (/dev/sda as against /dev/mapper/mapathb) > to get BLKZEROUT working on LV. The multipath target did not opt-in to supporting WRITE SAME. Please try this patch. From: Mike Snitzer <snitzer@xxxxxxxxxx> Subject: [PATCH] dm mpath: enable WRITE SAME support There is no reason to disallow WRITE SAME support. As far as multipath is concerned it is just another write request. Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> --- drivers/md/dm-mpath.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 51bb816..bdf26f5 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -907,6 +907,7 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc, ti->num_flush_bios = 1; ti->num_discard_bios = 1; + ti->num_write_same_bios = 1; return 0; -- 1.7.1 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
