--- qemu/block.h	2018/04/24 17:34:49	1.1.1.6
+++ qemu/block.h	2018/04/24 18:16:52	1.1.1.7
@@ -77,6 +77,10 @@ int bdrv_pread(BlockDriverState *bs, int
                void *buf, int count);
 int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
                 const void *buf, int count);
+int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
+    const void *buf, int count);
+int bdrv_write_sync(BlockDriverState *bs, int64_t sector_num,
+    const uint8_t *buf, int nb_sectors);
 int bdrv_truncate(BlockDriverState *bs, int64_t offset);
 int64_t bdrv_getlength(BlockDriverState *bs);
 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);