diff --git a/drm_hwcomposer.h b/drm_hwcomposer.h
index c82506c..cebdbee 100644
--- a/drm_hwcomposer.h
+++ b/drm_hwcomposer.h
@@ -60,6 +60,7 @@
   uint32_t gem_handles[4];
   uint32_t fb_id;
   int acquire_fence_fd;
+  void *priv;
 } hwc_drm_bo_t;
 
 int hwc_import_init(struct hwc_import_context **ctx);