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. > > From: Mike Snitzer <snitzer@xxxxxxxxxx> > Date: Tue, 30 Apr 2013 12:24:58 -0400 > Subject: [PATCH] dm table: fix logic bug in dm_table_supports_write_same > > If device_not_write_same_capable() returns true then the iterate_devices > loop in dm_table_supports_write_same() should return false. > > Reported-by: Bharata B Rao <bharata.rao@xxxxxxxxx> > Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx # v3.8+ > --- > drivers/md/dm-table.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c > index 3fe797f..d801682 100644 > --- a/drivers/md/dm-table.c > +++ b/drivers/md/dm-table.c > @@ -1445,7 +1445,7 @@ static bool dm_table_supports_write_same(struct dm_table *t) > return false; > > if (!ti->type->iterate_devices || > - !ti->type->iterate_devices(ti, device_not_write_same_capable, NULL)) > + ti->type->iterate_devices(ti, device_not_write_same_capable, NULL)) > return false; > } > > -- > 1.7.1 > -- http://raobharata.wordpress.com/ -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
