dm thin: emit ignore_discard in status when discards disabled

If "ignore_discard" is specified when creating the thin pool device then
discard support is disabled for that device.  The pool device's status
should reflect this fact rather than stating "no_discard_passdown"
(which implies discards are enabled but passdown is disabled).

Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index aeb9e20f5978..063fe04e60e9 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -2391,7 +2391,9 @@ static int pool_status(struct dm_target *ti, status_type_t type,
                 else
                         DMEMIT("rw ");
 
-                if (pool->pf.discard_enabled && pool->pf.discard_passdown)
+                if (!pool->pf.discard_enabled)
+                        DMEMIT("ignore_discard");
+                else if (pool->pf.discard_passdown)
                         DMEMIT("discard_passdown");
                 else
                         DMEMIT("no_discard_passdown");
@@ -2487,7 +2489,7 @@ static struct target_type pool_target = {
         .name = "thin-pool",
         .features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE |
                     DM_TARGET_IMMUTABLE,
-        .version = {1, 5, 0},
+        .version = {1, 6, 0},
         .module = THIS_MODULE,
         .ctr = pool_ctr,
         .dtr = pool_dtr,