From: Dan Mick <dan.mick@inktank.com>
Date: Tue, 6 Nov 2012 00:13:19 +0000 (-0800)
Subject: rbd: allow removal of image even if rbd_children deletion fails
X-Git-Tag: v0.54~19
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=241569c595a770183fa3597eeb66b709660123ad;p=ceph.git

rbd: allow removal of image even if rbd_children deletion fails

Users have been seeing failures where rbd rm is half-done; could be
because of outstanding watches on the rbd_header object.  The state
is that rbd_children no longer contains the child, but other pieces
remain; remove considers this a failure.

Fix: test for ENOENT from remove_child, and treat that as an ignorable
error and drive on.  Simulate this in copy.sh by removing the
rbd_children object altogether, which also results in ENOENT return
from remove_child.

Signed-off-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
---

diff --git a/qa/workunits/rbd/copy.sh b/qa/workunits/rbd/copy.sh
index b7ca82e6fce5..86a365cbf71f 100755
--- a/qa/workunits/rbd/copy.sh
+++ b/qa/workunits/rbd/copy.sh
@@ -153,6 +153,21 @@ test_remove() {
     rados -p rbd rm rbd_id.test2
     rbd rm test2
     rbd ls | wc -l | grep "^0$"
+
+    # remove with rbd_children object missing (and, by extension,
+    # with child not mentioned in rbd_children)
+    rbd create --new-format -s 1 test2
+    rbd snap create test2@snap
+    rbd snap protect test2@snap
+    rbd clone test2@snap clone
+
+    rados -p rbd rm rbd_children
+    rbd rm clone
+    rbd ls | grep clone | wc -l | grep '^0$'
+
+    rbd snap unprotect test2@snap
+    rbd snap rm test2@snap
+    rbd rm test2
 }
 
 test_locking() {
diff --git a/src/librbd/internal.cc b/src/librbd/internal.cc
index 703566013a78..6bf613cc3620 100644
--- a/src/librbd/internal.cc
+++ b/src/librbd/internal.cc
@@ -1216,7 +1216,7 @@ reprotect_and_return_err:
       if (scan_for_parents(ictx, parent_info.spec, CEPH_NOSNAP) == -ENOENT) {
 	r = cls_client::remove_child(&ictx->md_ctx, RBD_CHILDREN,
 				     parent_info.spec, id);
-	if (r < 0) {
+	if (r < 0 && r != -ENOENT) {
 	  lderr(cct) << "error removing child from children list" << dendl;
 	  return r;
 	}