diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 54d96e847f16..381b60d9e7ce 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1918,12 +1918,18 @@ static int iommu_dma_iova_link_swiotlb(struct device *dev,
 			return 0;
 	}
 
+	/*
+	 * After removing the partial head and tail, there may be no aligned
+	 * middle left to map.  The tail still gets bounced below.
+	 */
 	size -= iova_end_pad;
-	error = __dma_iova_link(dev, addr + mapped, phys + mapped, size, dir,
-			attrs);
-	if (error)
-		goto out_unmap;
-	mapped += size;
+	if (size) {
+		error = __dma_iova_link(dev, addr + mapped, phys + mapped,
+				size, dir, attrs);
+		if (error)
+			goto out_unmap;
+		mapped += size;
+	}
 
 	if (iova_end_pad) {
 		error = iommu_dma_iova_bounce_and_link(dev, addr + mapped,
@@ -1936,7 +1942,8 @@ static int iommu_dma_iova_link_swiotlb(struct device *dev,
 	return 0;
 
 out_unmap:
-	dma_iova_unlink(dev, state, 0, mapped, dir, attrs);
+	if (mapped)
+		dma_iova_unlink(dev, state, offset, mapped, dir, attrs);
 	return error;
 }