diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index a76a46e94a60..aa47d955de6b 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1296,6 +1296,14 @@ static size_t iommu_dma_opt_mapping_size(void)
 	return iova_rcache_range();
 }
 
+static size_t iommu_dma_max_mapping_size(struct device *dev)
+{
+	if (dev_is_untrusted(dev))
+		return swiotlb_max_mapping_size(dev);
+
+	return SIZE_MAX;
+}
+
 static const struct dma_map_ops iommu_dma_ops = {
 	.alloc			= iommu_dma_alloc,
 	.free			= iommu_dma_free,
@@ -1319,6 +1327,7 @@ static const struct dma_map_ops iommu_dma_ops = {
 	.unmap_resource		= iommu_dma_unmap_resource,
 	.get_merge_boundary	= iommu_dma_get_merge_boundary,
 	.opt_mapping_size	= iommu_dma_opt_mapping_size,
+	.max_mapping_size       = iommu_dma_max_mapping_size,
 };
 
 /*