diff --git a/linux-user/ioctls.h b/linux-user/ioctls.h
index 7245ff0..d8caf6f 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