RDMA/nes: Fix for incorrect MSS when TSO is on

In TSO handling code, skb_shared_info() is used to get the MSS
instead of the bool function skb_is_gso() (which always returns 1).
Signed-off-by: Tatyana Nikolova <Tatyana.E.Nikolova@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

drivers/infiniband/hw/nes/nes_nic.c

@@ -390,10 +390,10 @@ static int nes_nic_send(struct sk_buff *skb, struct net_device *netdev)
 		tcph = tcp_hdr(skb);
 		if (1) {
 			if (skb_is_gso(skb)) {
-				/* nes_debug(NES_DBG_NIC_TX, "%s: TSO request... seg size = %u\n",
-						netdev->name, skb_is_gso(skb)); */
+				/* nes_debug(NES_DBG_NIC_TX, "%s: TSO request... is_gso = %u seg size = %u\n",
+						netdev->name, skb_is_gso(skb), skb_shinfo(skb)->gso_size); */
 				wqe_misc |= NES_NIC_SQ_WQE_LSO_ENABLE |
-						NES_NIC_SQ_WQE_COMPLETION | (u16)skb_is_gso(skb);
+						NES_NIC_SQ_WQE_COMPLETION | (u16)skb_shinfo(skb)->gso_size;
 				set_wqe_32bit_value(nic_sqe->wqe_words, NES_NIC_SQ_WQE_LSO_INFO_IDX,
 						((u32)tcph->doff) |
 						(((u32)(((unsigned char *)tcph) - skb->data)) << 4));
@@ -597,10 +597,10 @@ static int nes_netdev_start_xmit(struct sk_buff *skb, struct net_device *netdev)
 					nes_debug(NES_DBG_NIC_TX, "ERROR: SKB header too big, headlen=%u, FIRST_FRAG_SIZE=%u\n",
 							original_first_length, NES_FIRST_FRAG_SIZE);
 					nes_debug(NES_DBG_NIC_TX, "%s Request to tx NIC packet length %u, headlen %u,"
-							" (%u frags), tso_size=%u\n",
+							" (%u frags), is_gso = %u tso_size=%u\n",
 							netdev->name,
 							skb->len, skb_headlen(skb),
-							skb_shinfo(skb)->nr_frags, skb_is_gso(skb));
+							skb_shinfo(skb)->nr_frags, skb_is_gso(skb), skb_shinfo(skb)->gso_size);
 				}
 				memcpy(&nesnic->first_frag_vbase[nesnic->sq_head].buffer,
 						skb->data, min(((unsigned int)NES_FIRST_FRAG_SIZE),
@@ -652,8 +652,8 @@ static int nes_netdev_start_xmit(struct sk_buff *skb, struct net_device *netdev)
 				} else {
 					nesnic->tx_skb[nesnic->sq_head] = NULL;
 				}
-				wqe_misc |= NES_NIC_SQ_WQE_COMPLETION | (u16)skb_is_gso(skb);
-				if ((tso_wqe_length + original_first_length) > skb_is_gso(skb)) {
+				wqe_misc |= NES_NIC_SQ_WQE_COMPLETION | (u16)skb_shinfo(skb)->gso_size;
+				if ((tso_wqe_length + original_first_length) > skb_shinfo(skb)->gso_size) {
 					wqe_misc |= NES_NIC_SQ_WQE_LSO_ENABLE;
 				} else {
 					iph->tot_len = htons(tso_wqe_length + original_first_length - nhoffset);