RDMA/siw: Only check attrs->cap.max_send_wr in siw_create_qp

We can just check max_send_wr here given both max_send_wr and
max_recv_wr are defined as u32 type, and we also need to ensure
num_sqe (derived from max_send_wr) shouldn't be zero.
Acked-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20231113115726.12762-16-guoqing.jiang@linux.devSigned-off-by: Leon Romanovsky <leon@kernel.org>

drivers/infiniband/sw/siw/siw_verbs.c

@@ -333,11 +333,10 @@ int siw_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *attrs,
 		goto err_atomic;
 	}
 	/*
-	 * NOTE: we allow for zero element SQ and RQ WQE's SGL's
-	 * but not for a QP unable to hold any WQE (SQ + RQ)
+	 * NOTE: we don't allow for a QP unable to hold any SQ WQE
 	 */
-	if (attrs->cap.max_send_wr + attrs->cap.max_recv_wr == 0) {
-		siw_dbg(base_dev, "QP must have send or receive queue\n");
+	if (attrs->cap.max_send_wr == 0) {
+		siw_dbg(base_dev, "QP must have send queue\n");
 		rv = -EINVAL;
 		goto err_atomic;
 	}
@@ -357,21 +356,14 @@ int siw_create_qp(struct ib_qp *ibqp, struct ib_qp_init_attr *attrs,
 	if (rv)
 		goto err_atomic;
 
-	num_sqe = attrs->cap.max_send_wr;
-	num_rqe = attrs->cap.max_recv_wr;
 
 	/* All queue indices are derived from modulo operations
 	 * on a free running 'get' (consumer) and 'put' (producer)
 	 * unsigned counter. Having queue sizes at power of two
 	 * avoids handling counter wrap around.
 	 */
-	if (num_sqe)
-		num_sqe = roundup_pow_of_two(num_sqe);
-	else {
-		/* Zero sized SQ is not supported */
-		rv = -EINVAL;
-		goto err_out_xa;
-	}
+	num_sqe = roundup_pow_of_two(attrs->cap.max_send_wr);
+	num_rqe = attrs->cap.max_recv_wr;
 	if (num_rqe)
 		num_rqe = roundup_pow_of_two(num_rqe);