diff --git a/drivers/xen/gntdev-dmabuf.c b/drivers/xen/gntdev-dmabuf.c
index da79992..4c13cbc 100644
--- a/drivers/xen/gntdev-dmabuf.c
+++ b/drivers/xen/gntdev-dmabuf.c
@@ -247,10 +247,9 @@
 
 		if (sgt) {
 			if (gntdev_dmabuf_attach->dir != DMA_NONE)
-				dma_unmap_sg_attrs(attach->dev, sgt->sgl,
-						   sgt->nents,
-						   gntdev_dmabuf_attach->dir,
-						   DMA_ATTR_SKIP_CPU_SYNC);
+				dma_unmap_sgtable(attach->dev, sgt,
+						  gntdev_dmabuf_attach->dir,
+						  DMA_ATTR_SKIP_CPU_SYNC);
 			sg_free_table(sgt);
 		}
 
@@ -288,8 +287,8 @@
 	sgt = dmabuf_pages_to_sgt(gntdev_dmabuf->pages,
 				  gntdev_dmabuf->nr_pages);
 	if (!IS_ERR(sgt)) {
-		if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir,
-				      DMA_ATTR_SKIP_CPU_SYNC)) {
+		if (dma_map_sgtable(attach->dev, sgt, dir,
+				    DMA_ATTR_SKIP_CPU_SYNC)) {
 			sg_free_table(sgt);
 			kfree(sgt);
 			sgt = ERR_PTR(-ENOMEM);
@@ -342,35 +341,12 @@
 	mutex_unlock(&priv->lock);
 }
 
-static void *dmabuf_exp_ops_kmap(struct dma_buf *dma_buf,
-				 unsigned long page_num)
-{
-	/* Not implemented. */
-	return NULL;
-}
-
-static void dmabuf_exp_ops_kunmap(struct dma_buf *dma_buf,
-				  unsigned long page_num, void *addr)
-{
-	/* Not implemented. */
-}
-
-static int dmabuf_exp_ops_mmap(struct dma_buf *dma_buf,
-			       struct vm_area_struct *vma)
-{
-	/* Not implemented. */
-	return 0;
-}
-
 static const struct dma_buf_ops dmabuf_exp_ops =  {
 	.attach = dmabuf_exp_ops_attach,
 	.detach = dmabuf_exp_ops_detach,
 	.map_dma_buf = dmabuf_exp_ops_map_dma_buf,
 	.unmap_dma_buf = dmabuf_exp_ops_unmap_dma_buf,
 	.release = dmabuf_exp_ops_release,
-	.map = dmabuf_exp_ops_kmap,
-	.unmap = dmabuf_exp_ops_kunmap,
-	.mmap = dmabuf_exp_ops_mmap,
 };
 
 struct gntdev_dmabuf_export_args {
@@ -446,7 +422,7 @@
 {
 	struct gntdev_grant_map *map;
 
-	if (unlikely(count <= 0))
+	if (unlikely(gntdev_test_page_count(count)))
 		return ERR_PTR(-EINVAL);
 
 	if ((dmabuf_flags & GNTDEV_DMA_FLAG_WC) &&
@@ -459,11 +435,6 @@
 	if (!map)
 		return ERR_PTR(-ENOMEM);
 
-	if (unlikely(gntdev_account_mapped_pages(count))) {
-		pr_debug("can't map %d pages: over limit\n", count);
-		gntdev_put_map(NULL, map);
-		return ERR_PTR(-ENOMEM);
-	}
 	return map;
 }
 
@@ -661,7 +632,7 @@
 
 	/* Now convert sgt to array of pages and check for page validity. */
 	i = 0;
-	for_each_sg_page(sgt->sgl, &sg_iter, sgt->nents, 0) {
+	for_each_sgtable_page(sgt, &sg_iter, 0) {
 		struct page *page = sg_page_iter_page(&sg_iter);
 		/*
 		 * Check if page is valid: this can happen if we are given
@@ -779,7 +750,7 @@
 	if (copy_from_user(&op, u, sizeof(op)) != 0)
 		return -EFAULT;
 
-	if (unlikely(op.count <= 0))
+	if (unlikely(gntdev_test_page_count(op.count)))
 		return -EINVAL;
 
 	refs = kcalloc(op.count, sizeof(*refs), GFP_KERNEL);
@@ -826,7 +797,7 @@
 	if (copy_from_user(&op, u, sizeof(op)) != 0)
 		return -EFAULT;
 
-	if (unlikely(op.count <= 0))
+	if (unlikely(gntdev_test_page_count(op.count)))
 		return -EINVAL;
 
 	gntdev_dmabuf = dmabuf_imp_to_refs(priv->dmabuf_priv,