Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches

# gpg: Signature made Thu 19 May 2016 16:09:27 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (31 commits)
  qemu-iotests: Fix regression in 136 on aio_read invalid
  qemu-iotests: Simplify 109 with unaligned qemu-img compare
  qemu-io: Fix recent UI updates
  block: clarify error message for qmp-eject
  qemu-iotests: Some more write_zeroes tests
  qcow2: Fix write_zeroes with partially allocated backing file cluster
  qcow2: fix condition in is_zero_cluster
  block: Propagate AioContext change to all children
  block: Remove BlockDriverState.blk
  block: Don't return throttling info in query-named-block-nodes
  block: Avoid bs->blk in bdrv_next()
  block: Add bdrv_has_blk()
  block: Remove bdrv_aio_multiwrite()
  blockjob: Don't touch BDS iostatus
  blockjob: Don't set iostatus of target
  block: User BdrvChild callback for device name
  block: Use BdrvChild callbacks for change_media/resize
  block: Don't check throttled reqs in bdrv_requests_pending()
  Revert "block: Forbid I/O throttling on nodes with multiple parents for 2.6"
  block: Remove bdrv_move_feature_fields()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

monitor.c

@@ -3431,11 +3431,13 @@ void host_net_remove_completion(ReadLineState *rs, int nb_args, const char *str)
 static void vm_completion(ReadLineState *rs, const char *str)
 {
     size_t len;
-    BlockDriverState *bs = NULL;
+    BlockDriverState *bs;
+    BdrvNextIterator *it = NULL;
 
     len = strlen(str);
     readline_set_completion_index(rs, len);
-    while ((bs = bdrv_next(bs))) {
+
+    while ((it = bdrv_next(it, &bs))) {
         SnapshotInfoList *snapshots, *snapshot;
         AioContext *ctx = bdrv_get_aio_context(bs);
         bool ok = false;