diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index cf52964f057b..0451e6ebc21a 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -146,7 +146,7 @@ xen_swiotlb_alloc_coherent(struct device *dev, size_t size,
 	void *ret;
 
 	/* Align the allocation to the Xen page size */
-	size = 1UL << (order + XEN_PAGE_SHIFT);
+	size = ALIGN(size, XEN_PAGE_SIZE);
 
 	ret = (void *)__get_free_pages(flags, get_order(size));
 	if (!ret)
@@ -178,7 +178,7 @@ xen_swiotlb_free_coherent(struct device *dev, size_t size, void *vaddr,
 	int order = get_order(size);
 
 	/* Convert the size to actually allocated. */
-	size = 1UL << (order + XEN_PAGE_SHIFT);
+	size = ALIGN(size, XEN_PAGE_SIZE);
 
 	if (WARN_ON_ONCE(dma_handle + size - 1 > dev->coherent_dma_mask) ||
 	    WARN_ON_ONCE(range_straddles_page_boundary(phys, size)))