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/raw-posix.c b/block/raw-posix.c
index d0393e0c44..d0960b85c4 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -734,10 +734,10 @@ static int raw_create(const char *filename, QEMUOptionParameter *options)
     return result;
 }
 
-static void raw_flush(BlockDriverState *bs)
+static int raw_flush(BlockDriverState *bs)
 {
     BDRVRawState *s = bs->opaque;
-    qemu_fdatasync(s->fd);
+    return qemu_fdatasync(s->fd);
 }