snapshot: correctly check device id of merged thin

When checking device id of a thin device that is just being
merged - the snapshot actually could have been already finished
which means  '-real' suffix for the LV is already gone and just LV
is there - so check explicitely for this condition and use
correct UUID for this case.

diff --git a/lib/activate/dev_manager.c b/lib/activate/dev_manager.c
index a2e9039172a05fc8effeb4744a8fdec75cb1b0c8..c87076c9dfe98f795d424a2335450d4a90d28be4 100644 (file)
--- a/lib/activate/dev_manager.c
+++ b/lib/activate/dev_manager.c
@@ -1679,6 +1679,9 @@ int dev_manager_thin_percent(struct dev_manager *dm,
        return 1;
 }
 
+/*
+ * Explore state of running DM table to obtain currently used deviceId
+ */
 int dev_manager_thin_device_id(struct dev_manager *dm,
                               const struct logical_volume *lv,
                               uint32_t *device_id)
@@ -1688,10 +1691,16 @@ int dev_manager_thin_device_id(struct dev_manager *dm,
        struct dm_info info;
        uint64_t start, length;
        char *params, *target_type = NULL;
+       const char *layer = lv_layer(lv);
        int r = 0;
 
+       if (lv_is_merging_origin(lv) && !lv_info(lv->vg->cmd, lv, 1, NULL, 0, 0))
+               /* If the merge has already happened, that table
+                * can already be using correct LV without -real layer */
+               layer = NULL;
+
        /* Build dlid for the thin layer */
-       if (!(dlid = build_dm_uuid(dm->mem, lv, lv_layer(lv))))
+       if (!(dlid = build_dm_uuid(dm->mem, lv, layer)))
                return_0;
 
        if (!(dmt = _setup_task_run(DM_DEVICE_TABLE, &info, NULL, dlid, 0, 0, 0, 0, 1, 0)))