RDMA/bnxt_re: Use for_each_sg_dma_page iterator on umem SGL

Use the for_each_sg_dma_page iterator variant to walk the umem DMA-mapped
SGL and get the page DMA address. This avoids the extra loop to iterate
pages in the SGE when for_each_sg iterator is used.

Additionally, purge umem->page_shift usage in the driver as its only
relevant for ODP MRs. Use system page size and shift instead.

Signed-off-by: Shiraz, Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/bnxt_re/ib_verbs.c

@@ -3553,19 +3553,14 @@ static int fill_umem_pbl_tbl(struct ib_umem *umem, u64 *pbl_tbl_orig,
 	u64 *pbl_tbl = pbl_tbl_orig;
 	u64 paddr;
 	u64 page_mask = (1ULL << page_shift) - 1;
-	int i, pages;
-	struct scatterlist *sg;
-	int entry;
-
-	for_each_sg(umem->sg_head.sgl, sg, umem->nmap, entry) {
-		pages = sg_dma_len(sg) >> PAGE_SHIFT;
-		for (i = 0; i < pages; i++) {
-			paddr = sg_dma_address(sg) + (i << PAGE_SHIFT);
-			if (pbl_tbl == pbl_tbl_orig)
-				*pbl_tbl++ = paddr & ~page_mask;
-			else if ((paddr & page_mask) == 0)
-				*pbl_tbl++ = paddr;
-		}
+	struct sg_dma_page_iter sg_iter;
+
+	for_each_sg_dma_page (umem->sg_head.sgl, &sg_iter, umem->nmap, 0) {
+		paddr = sg_page_iter_dma_address(&sg_iter);
+		if (pbl_tbl == pbl_tbl_orig)
+			*pbl_tbl++ = paddr & ~page_mask;
+		else if ((paddr & page_mask) == 0)
+			*pbl_tbl++ = paddr;
 	}
 	return pbl_tbl - pbl_tbl_orig;
 }
@@ -3628,7 +3623,7 @@ struct ib_mr *bnxt_re_reg_user_mr(struct ib_pd *ib_pd, u64 start, u64 length,
 		goto free_umem;
 	}
 
-	page_shift = umem->page_shift;
+	page_shift = PAGE_SHIFT;
 
 	if (!bnxt_re_page_size_ok(page_shift)) {
 		dev_err(rdev_to_dev(rdev), "umem page size unsupported!");

drivers/infiniband/hw/bnxt_re/qplib_res.c

@@ -85,7 +85,7 @@ static void __free_pbl(struct pci_dev *pdev, struct bnxt_qplib_pbl *pbl,
 static int __alloc_pbl(struct pci_dev *pdev, struct bnxt_qplib_pbl *pbl,
 		       struct scatterlist *sghead, u32 pages, u32 pg_size)
 {
-	struct scatterlist *sg;
+	struct sg_dma_page_iter sg_iter;
 	bool is_umem = false;
 	int i;
 
@@ -116,12 +116,13 @@ static int __alloc_pbl(struct pci_dev *pdev, struct bnxt_qplib_pbl *pbl,
 	} else {
 		i = 0;
 		is_umem = true;
-		for_each_sg(sghead, sg, pages, i) {
-			pbl->pg_map_arr[i] = sg_dma_address(sg);
-			pbl->pg_arr[i] = sg_virt(sg);
+		for_each_sg_dma_page (sghead, &sg_iter, pages, 0) {
+			pbl->pg_map_arr[i] = sg_page_iter_dma_address(&sg_iter);
+			pbl->pg_arr[i] = NULL;
 			if (!pbl->pg_arr[i])
 				goto fail;
 
+			i++;
 			pbl->pg_count++;
 		}
 	}