1 files changed, 1 insertions, 0 deletions
diff --git a/block_int.h b/block_int.h
index 137000e140..27e90b87e1 100644
--- a/block_int.h
+++ b/block_int.h
@@ -97,6 +97,7 @@ struct BlockDriverState {
     int locked;    /* if true, the media cannot temporarily be ejected */
     int encrypted; /* if true, the media is encrypted */
     int sg;        /* if true, the device is a /dev/sg* */
+    int autogrow;  /* if true, the backing store can auto-extend to allocate new extents */
     /* event callback when inserting/removing */
     void (*change_cb)(void *opaque);
     void *change_opaque;