block: Allow bdrv_flush to return errors

This changes bdrv_flush to return 0 on success and -errno in case of failure.
It's a requirement for implementing proper error handle in users of bdrv_flush.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/block/vdi.c b/block/vdi.c
index f72633cf19..3b51e532c4 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -900,10 +900,10 @@ static void vdi_close(BlockDriverState *bs)
 {
 }
 
-static void vdi_flush(BlockDriverState *bs)
+static int vdi_flush(BlockDriverState *bs)
 {
     logout("\n");
-    bdrv_flush(bs->file);
+    return bdrv_flush(bs->file);
 }