diff --git a/include/linux/dma_remapping.h b/include/linux/dma_remapping.h
index bbd8661..aaa12cb 100644
--- a/include/linux/dma_remapping.h
+++ b/include/linux/dma_remapping.h
@@ -25,9 +25,9 @@
 struct dmar_domain;
 struct root_entry;
 
-extern void free_dmar_iommu(struct intel_iommu *iommu);
 
 #ifdef CONFIG_DMAR
+extern void free_dmar_iommu(struct intel_iommu *iommu);
 extern int iommu_calculate_agaw(struct intel_iommu *iommu);
 extern int iommu_calculate_max_sagaw(struct intel_iommu *iommu);
 #else
@@ -39,6 +39,9 @@
 {
 	return 0;
 }
+static inline void free_dmar_iommu(struct intel_iommu *iommu)
+{
+}
 #endif
 
 extern int dmar_disabled;