vdi: Assign bs->file->bs to file in vdi_co_get_block_status

Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-10-git-send-email-famz@redhat.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

block/vdi.c

@@ -551,6 +551,7 @@ static int64_t coroutine_fn vdi_co_get_block_status(BlockDriverState *bs,
     offset = s->header.offset_data +
                               (uint64_t)bmap_entry * s->block_size +
                               sector_in_block * SECTOR_SIZE;
+    *file = bs->file->bs;
     return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | offset;
 }