+static inline void TCP_ECN_send_synack(struct tcp_sock *tp,
+ struct sk_buff *skb)
+{
+ TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_CWR;
+ if (!(tp->ecn_flags&TCP_ECN_OK))
+ TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_ECE;
+}
+
+static inline void TCP_ECN_send_syn(struct sock *sk, struct sk_buff *skb)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ tp->ecn_flags = 0;
+ if (sysctl_tcp_ecn) {
+ TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE|TCPCB_FLAG_CWR;
+ tp->ecn_flags = TCP_ECN_OK;
+ }
+}
+
+static __inline__ void
+TCP_ECN_make_synack(struct request_sock *req, struct tcphdr *th)
+{
+ if (inet_rsk(req)->ecn_ok)
+ th->ece = 1;
+}
+
+static inline void TCP_ECN_send(struct sock *sk, struct sk_buff *skb,
+ int tcp_header_len)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ if (tp->ecn_flags & TCP_ECN_OK) {
+ /* Not-retransmitted data segment: set ECT and inject CWR. */
+ if (skb->len != tcp_header_len &&
+ !before(TCP_SKB_CB(skb)->seq, tp->snd_nxt)) {
+ INET_ECN_xmit(sk);
+ if (tp->ecn_flags&TCP_ECN_QUEUE_CWR) {
+ tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR;
+ tcp_hdr(skb)->cwr = 1;
+ skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
+ }
+ } else {
+ /* ACK or retransmitted segment: clear ECT|CE */
+ INET_ECN_dontxmit(sk);
+ }
+ if (tp->ecn_flags & TCP_ECN_DEMAND_CWR)
+ tcp_hdr(skb)->ece = 1;
+ }
+}
+