rbd: tolerate -ENOENT for discard operations

Discard may try to delete an object from a non-layered image that does not exist.
If this occurs, the image already has no data in that range, so change the
result to success.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index de1520ccc0d4..835a96a09a6b 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1767,6 +1767,9 @@ static void rbd_osd_discard_callback(struct rbd_obj_request *obj_request)
          * it to our originally-requested length.
          */
         obj_request->xferred = obj_request->length;
+        /* discarding a non-existent object is not a problem */
+        if (obj_request->result == -ENOENT)
+                obj_request->result = 0;
         obj_request_done_set(obj_request);
 }