diff --git a/[refs] b/[refs]
index 513e2453a44c..2bbd1dd74125 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6e03f99803195e5aaf7f247db31b0d11857ccc35
+refs/heads/master: eecfffc154ffbfe70686a9905c090b488778c28e
diff --git a/trunk/include/linux/iommu-helper.h b/trunk/include/linux/iommu-helper.h
index c975caf75385..58f41107e4ae 100644
--- a/trunk/include/linux/iommu-helper.h
+++ b/trunk/include/linux/iommu-helper.h
@@ -1,3 +1,13 @@
+static inline unsigned long iommu_device_max_index(unsigned long size,
+						   unsigned long offset,
+						   u64 dma_mask)
+{
+	if (size + offset > dma_mask)
+		return dma_mask - offset + 1;
+	else
+		return size;
+}
+
 extern int iommu_is_span_boundary(unsigned int index, unsigned int nr,
 				  unsigned long shift,
 				  unsigned long boundary_size);