Merge remote-tracking branch 'kwolf/for-anthony' into staging

* kwolf/for-anthony:
  test-coroutine: add performance test for nesting
  coroutine: adding configure option for sigaltstack coroutine backend
  coroutine: adding configure choose mechanism for coroutine backend
  coroutine: adding sigaltstack method (.c source)
  qcow2: Reduce number of I/O requests
  qcow2: Add qcow2_alloc_clusters_at()
  qcow2: Factor out count_cow_clusters
  qmp: convert blockdev-snapshot-sync to a wrapper around transactions
  add mode field to blockdev-snapshot-sync transaction item
  rename blockdev-group-snapshot-sync
  qapi: complete implementation of unions
  use QSIMPLEQ_FOREACH_SAFE when freeing list elements
  Add 'make check-block'
  make check: Add qemu-iotests subset
  qemu-iotests: Mark some tests as quick
  qcow2: Add error messages in qcow2_truncate
  block: handle -EBUSY in bdrv_commit_all()
  qcow2: Add some tracing
  qed: do not evict in-use L2 table cache entries
  Group snapshot: Fix format name for backing file

1 files changed, 6 insertions, 2 deletions

diff --git a/block.c b/block.c
index 52ffe1494a..b88ee90817 100644
--- a/block.c
+++ b/block.c
@@ -1244,13 +1244,17 @@ ro_cleanup:
     return ret;
 }
 
-void bdrv_commit_all(void)
+int bdrv_commit_all(void)
 {
     BlockDriverState *bs;
 
     QTAILQ_FOREACH(bs, &bdrv_states, list) {
-        bdrv_commit(bs);
+        int ret = bdrv_commit(bs);
+        if (ret < 0) {
+            return ret;
+        }
     }
+    return 0;
 }
 
 struct BdrvTrackedRequest {