Update arch/ to use sg helpers

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
index 29af777..070a484 100644
--- a/arch/sparc64/kernel/iommu.c
+++ b/arch/sparc64/kernel/iommu.c
@@ -472,8 +472,7 @@
 	spin_unlock_irqrestore(&iommu->lock, flags);
 }
 
-#define SG_ENT_PHYS_ADDRESS(SG)	\
-	(__pa(page_address((SG)->page)) + (SG)->offset)
+#define SG_ENT_PHYS_ADDRESS(SG)	(__pa(sg_virt((SG))))
 
 static void fill_sg(iopte_t *iopte, struct scatterlist *sg,
 		    int nused, int nelems,
@@ -565,9 +564,7 @@
 	/* Fast path single entry scatterlists. */
 	if (nelems == 1) {
 		sglist->dma_address =
-			dma_4u_map_single(dev,
-					  (page_address(sglist->page) +
-					   sglist->offset),
+			dma_4u_map_single(dev, sg_virt(sglist),
 					  sglist->length, direction);
 		if (unlikely(sglist->dma_address == DMA_ERROR_CODE))
 			return 0;