*
* Version: $Id: tcp_output.c,v 1.146 2002/02/01 22:01:04 davem Exp $
*
- * Authors: Ross Biro, <bir7@leland.Stanford.Edu>
+ * Authors: Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Mark Evans, <evansmp@uhura.aston.ac.uk>
* Corey Minyard <wf-rch!minyard@relay.EU.net>
* will allow a single TSO frame to consume. Building TSO frames
* which are too large can cause TCP streams to be bursty.
*/
-int sysctl_tcp_tso_win_divisor = 8;
+int sysctl_tcp_tso_win_divisor = 3;
static inline void update_send_head(struct sock *sk, struct tcp_sock *tp,
struct sk_buff *skb)
u32 restart_cwnd = tcp_init_cwnd(tp, dst);
u32 cwnd = tp->snd_cwnd;
- if (tcp_is_vegas(tp))
- tcp_vegas_enable(tp);
+ tcp_ca_event(tp, CA_EVENT_CWND_RESTART);
tp->snd_ssthresh = tcp_current_ssthresh(tp);
restart_cwnd = min(restart_cwnd, cwnd);
tp->ack.pingpong = 1;
}
-static __inline__ void tcp_event_ack_sent(struct sock *sk)
+static __inline__ void tcp_event_ack_sent(struct sock *sk, unsigned int pkts)
{
struct tcp_sock *tp = tcp_sk(sk);
- tcp_dec_quickack_mode(tp);
+ tcp_dec_quickack_mode(tp, pkts);
tcp_clear_xmit_timer(sk, TCP_TIME_DACK);
}
#define SYSCTL_FLAG_WSCALE 0x2
#define SYSCTL_FLAG_SACK 0x4
+ /* If congestion control is doing timestamping */
+ if (tp->ca_ops->rtt_sample)
+ do_gettimeofday(&skb->stamp);
+
sysctl_flags = 0;
if (tcb->flags & TCPCB_FLAG_SYN) {
tcp_header_size = sizeof(struct tcphdr) + TCPOLEN_MSS;
(tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK));
}
- /*
- * If the connection is idle and we are restarting,
- * then we don't want to do any Vegas calculations
- * until we get fresh RTT samples. So when we
- * restart, we reset our Vegas state to a clean
- * slate. After we get acks for this flight of
- * packets, _then_ we can make Vegas calculations
- * again.
- */
- if (tcp_is_vegas(tp) && tcp_packets_in_flight(tp) == 0)
- tcp_vegas_enable(tp);
+ if (tcp_packets_in_flight(tp) == 0)
+ tcp_ca_event(tp, CA_EVENT_TX_START);
th = (struct tcphdr *) skb_push(skb, tcp_header_size);
skb->h.th = th;
tp->af_specific->send_check(sk, th, skb->len, skb);
if (tcb->flags & TCPCB_FLAG_ACK)
- tcp_event_ack_sent(sk);
+ tcp_event_ack_sent(sk, tcp_skb_pcount(skb));
if (skb->len != tcp_header_size)
tcp_event_data_sent(tp, skb, sk);
sk->sk_send_head = skb;
}
-static inline void tcp_tso_set_push(struct sk_buff *skb)
-{
- /* Force push to be on for any TSO frames to workaround
- * problems with busted implementations like Mac OS-X that
- * hold off socket receive wakeups until push is seen.
- */
- if (tcp_skb_pcount(skb) > 1)
- TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
-}
-
-/* Send _single_ skb sitting at the send head. This function requires
- * true push pending frames to setup probe timer etc.
- */
-void tcp_push_one(struct sock *sk, unsigned cur_mss)
+static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned int mss_now)
{
- struct tcp_sock *tp = tcp_sk(sk);
- struct sk_buff *skb = sk->sk_send_head;
-
- if (tcp_snd_test(sk, skb, cur_mss, TCP_NAGLE_PUSH)) {
- /* Send it out now. */
- TCP_SKB_CB(skb)->when = tcp_time_stamp;
- tcp_tso_set_push(skb);
- if (!tcp_transmit_skb(sk, skb_clone(skb, sk->sk_allocation))) {
- sk->sk_send_head = NULL;
- tp->snd_nxt = TCP_SKB_CB(skb)->end_seq;
- tcp_packets_out_inc(sk, tp, skb);
- return;
- }
- }
-}
-
-void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb)
-{
- struct tcp_sock *tp = tcp_sk(sk);
-
- if (skb->len <= tp->mss_cache_std ||
+ if (skb->len <= mss_now ||
!(sk->sk_route_caps & NETIF_F_TSO)) {
/* Avoid the costly divide in the normal
* non-TSO case.
} else {
unsigned int factor;
- factor = skb->len + (tp->mss_cache_std - 1);
- factor /= tp->mss_cache_std;
+ factor = skb->len + (mss_now - 1);
+ factor /= mss_now;
skb_shinfo(skb)->tso_segs = factor;
- skb_shinfo(skb)->tso_size = tp->mss_cache_std;
+ skb_shinfo(skb)->tso_size = mss_now;
}
}
* packet to the list. This won't be called frequently, I hope.
* Remember, these are still headerless SKBs at this point.
*/
-static int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len)
+static int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss_now)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *buff;
* skbs, which it never sent before. --ANK
*/
TCP_SKB_CB(buff)->when = TCP_SKB_CB(skb)->when;
+ buff->stamp = skb->stamp;
if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST) {
tp->lost_out -= tcp_skb_pcount(skb);
}
/* Fix up tso_factor for both original and new SKB. */
- tcp_set_skb_tso_segs(sk, skb);
- tcp_set_skb_tso_segs(sk, buff);
+ tcp_set_skb_tso_segs(sk, skb, mss_now);
+ tcp_set_skb_tso_segs(sk, buff, mss_now);
if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST) {
tp->lost_out += tcp_skb_pcount(skb);
}
/* Link BUFF into the send queue. */
+ skb_header_release(buff);
__skb_append(skb, buff);
return 0;
* factor and mss.
*/
if (tcp_skb_pcount(skb) > 1)
- tcp_set_skb_tso_segs(sk, skb);
+ tcp_set_skb_tso_segs(sk, skb, tcp_current_mss(sk, 1));
return 0;
}
/* And store cached results */
tp->pmtu_cookie = pmtu;
- tp->mss_cache = tp->mss_cache_std = mss_now;
+ tp->mss_cache = mss_now;
return mss_now;
}
* cannot be large. However, taking into account rare use of URG, this
* is not a big flaw.
*/
-
-unsigned int tcp_current_mss(struct sock *sk, int large)
+unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
{
struct tcp_sock *tp = tcp_sk(sk);
struct dst_entry *dst = __sk_dst_get(sk);
- unsigned int do_large, mss_now;
+ u32 mss_now;
+ u16 xmit_size_goal;
+ int doing_tso = 0;
+
+ mss_now = tp->mss_cache;
+
+ if (large_allowed &&
+ (sk->sk_route_caps & NETIF_F_TSO) &&
+ !tp->urg_mode)
+ doing_tso = 1;
- mss_now = tp->mss_cache_std;
if (dst) {
u32 mtu = dst_mtu(dst);
if (mtu != tp->pmtu_cookie)
mss_now = tcp_sync_mss(sk, mtu);
}
- do_large = (large &&
- (sk->sk_route_caps & NETIF_F_TSO) &&
- !tp->urg_mode);
+ if (tp->rx_opt.eff_sacks)
+ mss_now -= (TCPOLEN_SACK_BASE_ALIGNED +
+ (tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK));
- if (do_large) {
- unsigned int large_mss, factor, limit;
+ xmit_size_goal = mss_now;
- large_mss = 65535 - tp->af_specific->net_header_len -
+ if (doing_tso) {
+ xmit_size_goal = 65535 -
+ tp->af_specific->net_header_len -
tp->ext_header_len - tp->tcp_header_len;
- if (tp->max_window && large_mss > (tp->max_window>>1))
- large_mss = max((tp->max_window>>1),
- 68U - tp->tcp_header_len);
+ if (tp->max_window &&
+ (xmit_size_goal > (tp->max_window >> 1)))
+ xmit_size_goal = max((tp->max_window >> 1),
+ 68U - tp->tcp_header_len);
- factor = large_mss / mss_now;
+ xmit_size_goal -= (xmit_size_goal % mss_now);
+ }
+ tp->xmit_size_goal = xmit_size_goal;
- /* Always keep large mss multiple of real mss, but
- * do not exceed 1/tso_win_divisor of the congestion window
- * so we can keep the ACK clock ticking and minimize
- * bursting.
- */
- limit = tp->snd_cwnd;
- if (sysctl_tcp_tso_win_divisor)
- limit /= sysctl_tcp_tso_win_divisor;
- limit = max(1U, limit);
- if (factor > limit)
- factor = limit;
+ return mss_now;
+}
- tp->mss_cache = mss_now * factor;
+/* Congestion window validation. (RFC2861) */
- mss_now = tp->mss_cache;
+static inline void tcp_cwnd_validate(struct sock *sk, struct tcp_sock *tp)
+{
+ __u32 packets_out = tp->packets_out;
+
+ if (packets_out >= tp->snd_cwnd) {
+ /* Network is feed fully. */
+ tp->snd_cwnd_used = 0;
+ tp->snd_cwnd_stamp = tcp_time_stamp;
+ } else {
+ /* Network starves. */
+ if (tp->packets_out > tp->snd_cwnd_used)
+ tp->snd_cwnd_used = tp->packets_out;
+
+ if ((s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >= tp->rto)
+ tcp_cwnd_application_limited(sk);
}
+}
- if (tp->rx_opt.eff_sacks)
- mss_now -= (TCPOLEN_SACK_BASE_ALIGNED +
- (tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK));
- return mss_now;
+static unsigned int tcp_window_allows(struct tcp_sock *tp, struct sk_buff *skb, unsigned int mss_now, unsigned int cwnd)
+{
+ u32 window, cwnd_len;
+
+ window = (tp->snd_una + tp->snd_wnd - TCP_SKB_CB(skb)->seq);
+ cwnd_len = mss_now * cwnd;
+ return min(window, cwnd_len);
+}
+
+/* Can at least one segment of SKB be sent right now, according to the
+ * congestion window rules? If so, return how many segments are allowed.
+ */
+static inline unsigned int tcp_cwnd_test(struct tcp_sock *tp, struct sk_buff *skb)
+{
+ u32 in_flight, cwnd;
+
+ /* Don't be strict about the congestion window for the final FIN. */
+ if (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN)
+ return 1;
+
+ in_flight = tcp_packets_in_flight(tp);
+ cwnd = tp->snd_cwnd;
+ if (in_flight < cwnd)
+ return (cwnd - in_flight);
+
+ return 0;
+}
+
+/* This must be invoked the first time we consider transmitting
+ * SKB onto the wire.
+ */
+static inline int tcp_init_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned int mss_now)
+{
+ int tso_segs = tcp_skb_pcount(skb);
+
+ if (!tso_segs ||
+ (tso_segs > 1 &&
+ skb_shinfo(skb)->tso_size != mss_now)) {
+ tcp_set_skb_tso_segs(sk, skb, mss_now);
+ tso_segs = tcp_skb_pcount(skb);
+ }
+ return tso_segs;
+}
+
+static inline int tcp_minshall_check(const struct tcp_sock *tp)
+{
+ return after(tp->snd_sml,tp->snd_una) &&
+ !after(tp->snd_sml, tp->snd_nxt);
+}
+
+/* Return 0, if packet can be sent now without violation Nagle's rules:
+ * 1. It is full sized.
+ * 2. Or it contains FIN. (already checked by caller)
+ * 3. Or TCP_NODELAY was set.
+ * 4. Or TCP_CORK is not set, and all sent packets are ACKed.
+ * With Minshall's modification: all sent small packets are ACKed.
+ */
+
+static inline int tcp_nagle_check(const struct tcp_sock *tp,
+ const struct sk_buff *skb,
+ unsigned mss_now, int nonagle)
+{
+ return (skb->len < mss_now &&
+ ((nonagle&TCP_NAGLE_CORK) ||
+ (!nonagle &&
+ tp->packets_out &&
+ tcp_minshall_check(tp))));
+}
+
+/* Return non-zero if the Nagle test allows this packet to be
+ * sent now.
+ */
+static inline int tcp_nagle_test(struct tcp_sock *tp, struct sk_buff *skb,
+ unsigned int cur_mss, int nonagle)
+{
+ /* Nagle rule does not apply to frames, which sit in the middle of the
+ * write_queue (they have no chances to get new data).
+ *
+ * This is implemented in the callers, where they modify the 'nonagle'
+ * argument based upon the location of SKB in the send queue.
+ */
+ if (nonagle & TCP_NAGLE_PUSH)
+ return 1;
+
+ /* Don't use the nagle rule for urgent data (or for the final FIN). */
+ if (tp->urg_mode ||
+ (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN))
+ return 1;
+
+ if (!tcp_nagle_check(tp, skb, cur_mss, nonagle))
+ return 1;
+
+ return 0;
+}
+
+/* Does at least the first segment of SKB fit into the send window? */
+static inline int tcp_snd_wnd_test(struct tcp_sock *tp, struct sk_buff *skb, unsigned int cur_mss)
+{
+ u32 end_seq = TCP_SKB_CB(skb)->end_seq;
+
+ if (skb->len > cur_mss)
+ end_seq = TCP_SKB_CB(skb)->seq + cur_mss;
+
+ return !after(end_seq, tp->snd_una + tp->snd_wnd);
+}
+
+/* This checks if the data bearing packet SKB (usually sk->sk_send_head)
+ * should be put on the wire right now. If so, it returns the number of
+ * packets allowed by the congestion window.
+ */
+static unsigned int tcp_snd_test(struct sock *sk, struct sk_buff *skb,
+ unsigned int cur_mss, int nonagle)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ unsigned int cwnd_quota;
+
+ tcp_init_tso_segs(sk, skb, cur_mss);
+
+ if (!tcp_nagle_test(tp, skb, cur_mss, nonagle))
+ return 0;
+
+ cwnd_quota = tcp_cwnd_test(tp, skb);
+ if (cwnd_quota &&
+ !tcp_snd_wnd_test(tp, skb, cur_mss))
+ cwnd_quota = 0;
+
+ return cwnd_quota;
+}
+
+static inline int tcp_skb_is_last(const struct sock *sk,
+ const struct sk_buff *skb)
+{
+ return skb->next == (struct sk_buff *)&sk->sk_write_queue;
+}
+
+int tcp_may_send_now(struct sock *sk, struct tcp_sock *tp)
+{
+ struct sk_buff *skb = sk->sk_send_head;
+
+ return (skb &&
+ tcp_snd_test(sk, skb, tcp_current_mss(sk, 1),
+ (tcp_skb_is_last(sk, skb) ?
+ TCP_NAGLE_PUSH :
+ tp->nonagle)));
+}
+
+/* Trim TSO SKB to LEN bytes, put the remaining data into a new packet
+ * which is put after SKB on the list. It is very much like
+ * tcp_fragment() except that it may make several kinds of assumptions
+ * in order to speed up the splitting operation. In particular, we
+ * know that all the data is in scatter-gather pages, and that the
+ * packet has never been sent out before (and thus is not cloned).
+ */
+static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len, unsigned int mss_now)
+{
+ struct sk_buff *buff;
+ int nlen = skb->len - len;
+ u16 flags;
+
+ /* All of a TSO frame must be composed of paged data. */
+ BUG_ON(skb->len != skb->data_len);
+
+ buff = sk_stream_alloc_pskb(sk, 0, 0, GFP_ATOMIC);
+ if (unlikely(buff == NULL))
+ return -ENOMEM;
+
+ buff->truesize = nlen;
+ skb->truesize -= nlen;
+
+ /* Correct the sequence numbers. */
+ TCP_SKB_CB(buff)->seq = TCP_SKB_CB(skb)->seq + len;
+ TCP_SKB_CB(buff)->end_seq = TCP_SKB_CB(skb)->end_seq;
+ TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(buff)->seq;
+
+ /* PSH and FIN should only be set in the second packet. */
+ flags = TCP_SKB_CB(skb)->flags;
+ TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN|TCPCB_FLAG_PSH);
+ TCP_SKB_CB(buff)->flags = flags;
+
+ /* This packet was never sent out yet, so no SACK bits. */
+ TCP_SKB_CB(buff)->sacked = 0;
+
+ buff->ip_summed = skb->ip_summed = CHECKSUM_HW;
+ skb_split(skb, buff, len);
+
+ /* Fix up tso_factor for both original and new SKB. */
+ tcp_set_skb_tso_segs(sk, skb, mss_now);
+ tcp_set_skb_tso_segs(sk, buff, mss_now);
+
+ /* Link BUFF into the send queue. */
+ skb_header_release(buff);
+ __skb_append(skb, buff);
+
+ return 0;
+}
+
+/* Try to defer sending, if possible, in order to minimize the amount
+ * of TSO splitting we do. View it as a kind of TSO Nagle test.
+ *
+ * This algorithm is from John Heffner.
+ */
+static int tcp_tso_should_defer(struct sock *sk, struct tcp_sock *tp, struct sk_buff *skb)
+{
+ u32 send_win, cong_win, limit, in_flight;
+
+ if (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN)
+ return 0;
+
+ if (tp->ca_state != TCP_CA_Open)
+ return 0;
+
+ in_flight = tcp_packets_in_flight(tp);
+
+ BUG_ON(tcp_skb_pcount(skb) <= 1 ||
+ (tp->snd_cwnd <= in_flight));
+
+ send_win = (tp->snd_una + tp->snd_wnd) - TCP_SKB_CB(skb)->seq;
+
+ /* From in_flight test above, we know that cwnd > in_flight. */
+ cong_win = (tp->snd_cwnd - in_flight) * tp->mss_cache;
+
+ limit = min(send_win, cong_win);
+
+ /* If sk_send_head can be sent fully now, just do it. */
+ if (skb->len <= limit)
+ return 0;
+
+ if (sysctl_tcp_tso_win_divisor) {
+ u32 chunk = min(tp->snd_wnd, tp->snd_cwnd * tp->mss_cache);
+
+ /* If at least some fraction of a window is available,
+ * just use it.
+ */
+ chunk /= sysctl_tcp_tso_win_divisor;
+ if (limit >= chunk)
+ return 0;
+ } else {
+ /* Different approach, try not to defer past a single
+ * ACK. Receiver should ACK every other full sized
+ * frame, so if we have space for more than 3 frames
+ * then send now.
+ */
+ if (limit > tcp_max_burst(tp) * tp->mss_cache)
+ return 0;
+ }
+
+ /* Ok, it looks like it is advisable to defer. */
+ return 1;
}
/* This routine writes packets to the network. It advances the
* Returns 1, if no segments are in flight and we have queued segments, but
* cannot send anything now because of SWS or another problem.
*/
-int tcp_write_xmit(struct sock *sk, int nonagle)
+static int tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle)
{
struct tcp_sock *tp = tcp_sk(sk);
- unsigned int mss_now;
+ struct sk_buff *skb;
+ unsigned int tso_segs, sent_pkts;
+ int cwnd_quota;
/* If we are closed, the bytes will have to remain here.
* In time closedown will finish, we empty the write queue and all
* will be happy.
*/
- if (sk->sk_state != TCP_CLOSE) {
- struct sk_buff *skb;
- int sent_pkts = 0;
+ if (unlikely(sk->sk_state == TCP_CLOSE))
+ return 0;
+
+ skb = sk->sk_send_head;
+ if (unlikely(!skb))
+ return 0;
+
+ tso_segs = tcp_init_tso_segs(sk, skb, mss_now);
+ cwnd_quota = tcp_cwnd_test(tp, skb);
+ if (unlikely(!cwnd_quota))
+ goto out;
+
+ sent_pkts = 0;
+ while (likely(tcp_snd_wnd_test(tp, skb, mss_now))) {
+ BUG_ON(!tso_segs);
+
+ if (tso_segs == 1) {
+ if (unlikely(!tcp_nagle_test(tp, skb, mss_now,
+ (tcp_skb_is_last(sk, skb) ?
+ nonagle : TCP_NAGLE_PUSH))))
+ break;
+ } else {
+ if (tcp_tso_should_defer(sk, tp, skb))
+ break;
+ }
- /* Account for SACKS, we may need to fragment due to this.
- * It is just like the real MSS changing on us midstream.
- * We also handle things correctly when the user adds some
- * IP options mid-stream. Silly to do, but cover it.
- */
- mss_now = tcp_current_mss(sk, 1);
-
- while ((skb = sk->sk_send_head) &&
- tcp_snd_test(sk, skb, mss_now,
- tcp_skb_is_last(sk, skb) ? nonagle :
- TCP_NAGLE_PUSH)) {
- if (skb->len > mss_now) {
- if (tcp_fragment(sk, skb, mss_now))
+ if (tso_segs > 1) {
+ u32 limit = tcp_window_allows(tp, skb,
+ mss_now, cwnd_quota);
+
+ if (skb->len < limit) {
+ unsigned int trim = skb->len % mss_now;
+
+ if (trim)
+ limit = skb->len - trim;
+ }
+ if (skb->len > limit) {
+ if (tso_fragment(sk, skb, limit, mss_now))
break;
}
-
- TCP_SKB_CB(skb)->when = tcp_time_stamp;
- tcp_tso_set_push(skb);
- if (tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)))
+ } else if (unlikely(skb->len > mss_now)) {
+ if (unlikely(tcp_fragment(sk, skb, mss_now, mss_now)))
break;
+ }
- /* Advance the send_head. This one is sent out.
- * This call will increment packets_out.
- */
- update_send_head(sk, tp, skb);
+ TCP_SKB_CB(skb)->when = tcp_time_stamp;
+
+ if (unlikely(tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC))))
+ break;
+
+ /* Advance the send_head. This one is sent out.
+ * This call will increment packets_out.
+ */
+ update_send_head(sk, tp, skb);
+
+ tcp_minshall_update(tp, mss_now, skb);
+ sent_pkts++;
+
+ /* Do not optimize this to use tso_segs. If we chopped up
+ * the packet above, tso_segs will no longer be valid.
+ */
+ cwnd_quota -= tcp_skb_pcount(skb);
+
+ BUG_ON(cwnd_quota < 0);
+ if (!cwnd_quota)
+ break;
+
+ skb = sk->sk_send_head;
+ if (!skb)
+ break;
+ tso_segs = tcp_init_tso_segs(sk, skb, mss_now);
+ }
+
+ if (likely(sent_pkts)) {
+ tcp_cwnd_validate(sk, tp);
+ return 0;
+ }
+out:
+ return !tp->packets_out && sk->sk_send_head;
+}
+
+/* Push out any pending frames which were held back due to
+ * TCP_CORK or attempt at coalescing tiny packets.
+ * The socket must be locked by the caller.
+ */
+void __tcp_push_pending_frames(struct sock *sk, struct tcp_sock *tp,
+ unsigned int cur_mss, int nonagle)
+{
+ struct sk_buff *skb = sk->sk_send_head;
- tcp_minshall_update(tp, mss_now, skb);
- sent_pkts = 1;
+ if (skb) {
+ if (tcp_write_xmit(sk, cur_mss, nonagle))
+ tcp_check_probe_timer(sk, tp);
+ }
+}
+
+/* Send _single_ skb sitting at the send head. This function requires
+ * true push pending frames to setup probe timer etc.
+ */
+void tcp_push_one(struct sock *sk, unsigned int mss_now)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct sk_buff *skb = sk->sk_send_head;
+ unsigned int tso_segs, cwnd_quota;
+
+ BUG_ON(!skb || skb->len < mss_now);
+
+ tso_segs = tcp_init_tso_segs(sk, skb, mss_now);
+ cwnd_quota = tcp_snd_test(sk, skb, mss_now, TCP_NAGLE_PUSH);
+
+ if (likely(cwnd_quota)) {
+ BUG_ON(!tso_segs);
+
+ if (tso_segs > 1) {
+ u32 limit = tcp_window_allows(tp, skb,
+ mss_now, cwnd_quota);
+
+ if (skb->len < limit) {
+ unsigned int trim = skb->len % mss_now;
+
+ if (trim)
+ limit = skb->len - trim;
+ }
+ if (skb->len > limit) {
+ if (unlikely(tso_fragment(sk, skb, limit, mss_now)))
+ return;
+ }
+ } else if (unlikely(skb->len > mss_now)) {
+ if (unlikely(tcp_fragment(sk, skb, mss_now, mss_now)))
+ return;
}
- if (sent_pkts) {
+ /* Send it out now. */
+ TCP_SKB_CB(skb)->when = tcp_time_stamp;
+
+ if (likely(!tcp_transmit_skb(sk, skb_clone(skb, sk->sk_allocation)))) {
+ update_send_head(sk, tp, skb);
tcp_cwnd_validate(sk, tp);
- return 0;
+ return;
}
-
- return !tp->packets_out && sk->sk_send_head;
}
- return 0;
}
/* This function returns the amount that we can raise the
if (sk->sk_route_caps & NETIF_F_TSO) {
sk->sk_route_caps &= ~NETIF_F_TSO;
sock_set_flag(sk, SOCK_NO_LARGESEND);
- tp->mss_cache = tp->mss_cache_std;
}
if (tcp_trim_head(sk, skb, tp->snd_una - TCP_SKB_CB(skb)->seq))
int old_factor = tcp_skb_pcount(skb);
int new_factor;
- if (tcp_fragment(sk, skb, cur_mss))
+ if (tcp_fragment(sk, skb, cur_mss, cur_mss))
return -ENOMEM; /* We'll try again later. */
/* New SKB created, account for it. */
* is still in somebody's hands, else make a clone.
*/
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- tcp_tso_set_push(skb);
err = tcp_transmit_skb(sk, (skb_cloned(skb) ?
pskb_copy(skb, GFP_ATOMIC):
* was unread data in the receive queue. This behavior is recommended
* by draft-ietf-tcpimpl-prob-03.txt section 3.10. -DaveM
*/
-void tcp_send_active_reset(struct sock *sk, int priority)
+void tcp_send_active_reset(struct sock *sk, unsigned int __nocast priority)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
* Prepare a SYN-ACK.
*/
struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst,
- struct open_request *req)
+ struct request_sock *req)
{
+ struct inet_request_sock *ireq = inet_rsk(req);
struct tcp_sock *tp = tcp_sk(sk);
struct tcphdr *th;
int tcp_header_size;
skb->dst = dst_clone(dst);
tcp_header_size = (sizeof(struct tcphdr) + TCPOLEN_MSS +
- (req->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0) +
- (req->wscale_ok ? TCPOLEN_WSCALE_ALIGNED : 0) +
+ (ireq->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0) +
+ (ireq->wscale_ok ? TCPOLEN_WSCALE_ALIGNED : 0) +
/* SACK_PERM is in the place of NOP NOP of TS */
- ((req->sack_ok && !req->tstamp_ok) ? TCPOLEN_SACKPERM_ALIGNED : 0));
+ ((ireq->sack_ok && !ireq->tstamp_ok) ? TCPOLEN_SACKPERM_ALIGNED : 0));
skb->h.th = th = (struct tcphdr *) skb_push(skb, tcp_header_size);
memset(th, 0, sizeof(struct tcphdr));
th->syn = 1;
th->ack = 1;
if (dst->dev->features&NETIF_F_TSO)
- req->ecn_ok = 0;
+ ireq->ecn_ok = 0;
TCP_ECN_make_synack(req, th);
th->source = inet_sk(sk)->sport;
- th->dest = req->rmt_port;
- TCP_SKB_CB(skb)->seq = req->snt_isn;
+ th->dest = ireq->rmt_port;
+ TCP_SKB_CB(skb)->seq = tcp_rsk(req)->snt_isn;
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq + 1;
TCP_SKB_CB(skb)->sacked = 0;
skb_shinfo(skb)->tso_segs = 1;
skb_shinfo(skb)->tso_size = 0;
th->seq = htonl(TCP_SKB_CB(skb)->seq);
- th->ack_seq = htonl(req->rcv_isn + 1);
+ th->ack_seq = htonl(tcp_rsk(req)->rcv_isn + 1);
if (req->rcv_wnd == 0) { /* ignored for retransmitted syns */
__u8 rcv_wscale;
/* Set this up on the first call only */
req->window_clamp = tp->window_clamp ? : dst_metric(dst, RTAX_WINDOW);
/* tcp_full_space because it is guaranteed to be the first packet */
tcp_select_initial_window(tcp_full_space(sk),
- dst_metric(dst, RTAX_ADVMSS) - (req->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0),
+ dst_metric(dst, RTAX_ADVMSS) - (ireq->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0),
&req->rcv_wnd,
&req->window_clamp,
- req->wscale_ok,
+ ireq->wscale_ok,
&rcv_wscale);
- req->rcv_wscale = rcv_wscale;
+ ireq->rcv_wscale = rcv_wscale;
}
/* RFC1323: The window in SYN & SYN/ACK segments is never scaled. */
th->window = htons(req->rcv_wnd);
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- tcp_syn_build_options((__u32 *)(th + 1), dst_metric(dst, RTAX_ADVMSS), req->tstamp_ok,
- req->sack_ok, req->wscale_ok, req->rcv_wscale,
+ tcp_syn_build_options((__u32 *)(th + 1), dst_metric(dst, RTAX_ADVMSS), ireq->tstamp_ok,
+ ireq->sack_ok, ireq->wscale_ok, ireq->rcv_wscale,
TCP_SKB_CB(skb)->when,
req->ts_recent);
tp->window_clamp = dst_metric(dst, RTAX_WINDOW);
tp->advmss = dst_metric(dst, RTAX_ADVMSS);
tcp_initialize_rcv_mss(sk);
- tcp_ca_init(tp);
tcp_select_initial_window(tcp_full_space(sk),
tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0),
TCP_SKB_CB(buff)->end_seq = tp->write_seq;
tp->snd_nxt = tp->write_seq;
tp->pushed_seq = tp->write_seq;
- tcp_ca_init(tp);
/* Send it off. */
TCP_SKB_CB(buff)->when = tcp_time_stamp;
skb->len > mss) {
seg_size = min(seg_size, mss);
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
- if (tcp_fragment(sk, skb, seg_size))
+ if (tcp_fragment(sk, skb, seg_size, mss))
return -1;
/* SWS override triggered forced fragmentation.
* Disable TSO, the connection is too sick. */
if (sk->sk_route_caps & NETIF_F_TSO) {
sock_set_flag(sk, SOCK_NO_LARGESEND);
sk->sk_route_caps &= ~NETIF_F_TSO;
- tp->mss_cache = tp->mss_cache_std;
}
} else if (!tcp_skb_pcount(skb))
- tcp_set_skb_tso_segs(sk, skb);
+ tcp_set_skb_tso_segs(sk, skb, mss);
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- tcp_tso_set_push(skb);
err = tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC));
if (!err) {
update_send_head(sk, tp, skb);
projects / linux-2.6-omap-h63xx.git / blobdiff