diff --git a/linux-user/ioctls.h b/linux-user/ioctls.h
index 5b70f92c030879b0e1653a1fbc8d400f5964fa1f..eb96a084c227aae2752b140c4b363c1e1c2e492d 100644
--- a/linux-user/ioctls.h
+++ b/linux-user/ioctls.h
@@ -75,6 +75,7 @@
      IOCTL(BLKRASET, 0, TYPE_INT)
      IOCTL(BLKRAGET, IOC_R, MK_PTR(TYPE_LONG))
      IOCTL(BLKSSZGET, IOC_R, MK_PTR(TYPE_LONG))
+     IOCTL(BLKBSZGET, IOC_R, MK_PTR(TYPE_INT))
 #ifdef FIBMAP
      IOCTL(FIBMAP, IOC_W | IOC_R, MK_PTR(TYPE_LONG))
 #endif