diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index ac8d488..24579a0 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -90,4 +90,11 @@
 	TYPE tmp;						\
 	offsetof(TYPE, MEMBER) + sizeof(tmp.MEMBER); })		\
 
+/*
+ * External user API
+ */
+extern struct vfio_group *vfio_group_get_external_user(struct file *filep);
+extern void vfio_group_put_external_user(struct vfio_group *group);
+extern int vfio_external_user_iommu_id(struct vfio_group *group);
+
 #endif /* VFIO_H */