Update arch/ to use sg helpers

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 306a6f7..2d0c9ef 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -307,7 +307,7 @@
 			continue;
 		}
 		/* Allocate iommu entries for that segment */
-		vaddr = (unsigned long)page_address(s->page) + s->offset;
+		vaddr = (unsigned long) sg_virt(s);
 		npages = iommu_num_pages(vaddr, slen);
 		entry = iommu_range_alloc(tbl, npages, &handle, mask >> IOMMU_PAGE_SHIFT, 0);