diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 6894999..b944b2b 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -249,6 +249,7 @@
 					   struct notifier_block *nb);
 extern int iommu_group_id(struct iommu_group *group);
 extern struct iommu_group *iommu_group_get_for_dev(struct device *dev);
+extern struct iommu_domain *iommu_group_default_domain(struct iommu_group *);
 
 extern int iommu_domain_get_attr(struct iommu_domain *domain, enum iommu_attr,
 				 void *data);