diff --git a/block.h b/block.h
index 78ecfac..1f55f6d 100644
--- a/block.h
+++ b/block.h
@@ -14,6 +14,8 @@ typedef struct BlockDriverInfo {
     int cluster_size;
     /* offset at which the VM state can be saved (0 if not possible) */
     int64_t vm_state_offset;
+    int drv_type;
+    const char *drv_work;
 } BlockDriverInfo;