[Qemu-block] [PATCH v4] block/vdi: Use bdrv_flush after metadata updates

[Zhe Qiu]

In reference to b0ad5a45...078a458e, metadata writes to 
qcow2/cow/qcow/vpc/vmdk are all synced prior to succeeding writes.

Only when write is successful that bdrv_flush is called.

Signed-off-by: Zhe Qiu <phoea...@gmail.com>
---
 block/vdi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/block/vdi.c b/block/vdi.c
index 7642ef3..dfe8ade 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -713,6 +713,9 @@ static int vdi_co_write(BlockDriverState *bs,
         logout("will write %u block map sectors starting from entry %u\n",
                n_sectors, bmap_first);
         ret = bdrv_write(bs->file, offset, base, n_sectors);
+        if (ret >= 0) {
+            ret = bdrv_flush(bs->file);
+        }
     }
 
     return ret;
-- 
2.4.0