RDMA/siw: Introduce siw_get_page

Add the wrapper function to get either pbl page or umem page.
Acked-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20231113115726.12762-2-guoqing.jiang@linux.devSigned-off-by: Leon Romanovsky <leon@kernel.org>

drivers/infiniband/sw/siw/siw_qp_tx.c

@@ -34,6 +34,15 @@ static struct page *siw_get_pblpage(struct siw_mem *mem, u64 addr, int *idx)
 	return NULL;
 }
 
+static struct page *siw_get_page(struct siw_mem *mem, struct siw_sge *sge,
+				 unsigned long offset, int *pbl_idx)
+{
+	if (!mem->is_pbl)
+		return siw_get_upage(mem->umem, sge->laddr + offset);
+	else
+		return siw_get_pblpage(mem, sge->laddr + offset, pbl_idx);
+}
+
 /*
  * Copy short payload at provided destination payload address
  */
@@ -67,11 +76,7 @@ static int siw_try_1seg(struct siw_iwarp_tx *c_tx, void *paddr)
 			char *buffer;
 			int pbl_idx = 0;
 
-			if (!mem->is_pbl)
-				p = siw_get_upage(mem->umem, sge->laddr);
-			else
-				p = siw_get_pblpage(mem, sge->laddr, &pbl_idx);
-
+			p = siw_get_page(mem, sge, 0, &pbl_idx);
 			if (unlikely(!p))
 				return -EFAULT;
 
@@ -85,13 +90,7 @@ static int siw_try_1seg(struct siw_iwarp_tx *c_tx, void *paddr)
 				memcpy(paddr, buffer + off, part);
 				kunmap_local(buffer);
 
-				if (!mem->is_pbl)
-					p = siw_get_upage(mem->umem,
-							  sge->laddr + part);
-				else
-					p = siw_get_pblpage(mem,
-							    sge->laddr + part,
-							    &pbl_idx);
+				p = siw_get_page(mem, sge, part, &pbl_idx);
 				if (unlikely(!p))
 					return -EFAULT;
 
@@ -498,13 +497,7 @@ static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s)
 			if (!is_kva) {
 				struct page *p;
 
-				if (mem->is_pbl)
-					p = siw_get_pblpage(
-						mem, sge->laddr + sge_off,
-						&pbl_idx);
-				else
-					p = siw_get_upage(mem->umem,
-							  sge->laddr + sge_off);
+				p = siw_get_page(mem, sge, sge_off, &pbl_idx);
 				if (unlikely(!p)) {
 					siw_unmap_pages(iov, kmap_mask, seg);
 					wqe->processed -= c_tx->bytes_unsent;