*
* 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>
/* People can turn this off for buggy TCP's found in printers etc. */
int sysctl_tcp_retrans_collapse = 1;
-static __inline__
-void update_send_head(struct sock *sk, struct tcp_opt *tp, struct sk_buff *skb)
+/* This limits the percentage of the congestion window which we
+ * 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 = 3;
+
+static void update_send_head(struct sock *sk, struct tcp_sock *tp,
+ struct sk_buff *skb)
{
- tp->send_head = skb->next;
- if (tp->send_head == (struct sk_buff *)&sk->sk_write_queue)
- tp->send_head = NULL;
+ sk->sk_send_head = skb->next;
+ if (sk->sk_send_head == (struct sk_buff *)&sk->sk_write_queue)
+ sk->sk_send_head = NULL;
tp->snd_nxt = TCP_SKB_CB(skb)->end_seq;
- if (tp->packets_out++ == 0)
- tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
+ tcp_packets_out_inc(sk, tp, skb);
}
/* SND.NXT, if window was not shrunk.
* Anything in between SND.UNA...SND.UNA+SND.WND also can be already
* invalid. OK, let's make this for now:
*/
-static __inline__ __u32 tcp_acceptable_seq(struct sock *sk, struct tcp_opt *tp)
+static inline __u32 tcp_acceptable_seq(struct sock *sk, struct tcp_sock *tp)
{
if (!before(tp->snd_una+tp->snd_wnd, tp->snd_nxt))
return tp->snd_nxt;
*/
static __u16 tcp_advertise_mss(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct dst_entry *dst = __sk_dst_get(sk);
int mss = tp->advmss;
/* RFC2861. Reset CWND after idle period longer RTO to "restart window".
* This is the first part of cwnd validation mechanism. */
-static void tcp_cwnd_restart(struct tcp_opt *tp, struct dst_entry *dst)
+static void tcp_cwnd_restart(struct sock *sk, struct dst_entry *dst)
{
+ struct tcp_sock *tp = tcp_sk(sk);
s32 delta = tcp_time_stamp - tp->lsndtime;
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(sk, CA_EVENT_CWND_RESTART);
- tp->snd_ssthresh = tcp_current_ssthresh(tp);
+ tp->snd_ssthresh = tcp_current_ssthresh(sk);
restart_cwnd = min(restart_cwnd, cwnd);
- while ((delta -= tp->rto) > 0 && cwnd > restart_cwnd)
+ while ((delta -= inet_csk(sk)->icsk_rto) > 0 && cwnd > restart_cwnd)
cwnd >>= 1;
tp->snd_cwnd = max(cwnd, restart_cwnd);
tp->snd_cwnd_stamp = tcp_time_stamp;
tp->snd_cwnd_used = 0;
}
-static __inline__ void tcp_event_data_sent(struct tcp_opt *tp, struct sk_buff *skb, struct sock *sk)
+static void tcp_event_data_sent(struct tcp_sock *tp,
+ struct sk_buff *skb, struct sock *sk)
{
- u32 now = tcp_time_stamp;
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ const u32 now = tcp_time_stamp;
- if (!tp->packets_out && (s32)(now - tp->lsndtime) > tp->rto)
- tcp_cwnd_restart(tp, __sk_dst_get(sk));
+ if (!tp->packets_out && (s32)(now - tp->lsndtime) > icsk->icsk_rto)
+ tcp_cwnd_restart(sk, __sk_dst_get(sk));
tp->lsndtime = now;
/* If it is a reply for ato after last received
* packet, enter pingpong mode.
*/
- if ((u32)(now - tp->ack.lrcvtime) < tp->ack.ato)
- tp->ack.pingpong = 1;
+ if ((u32)(now - icsk->icsk_ack.lrcvtime) < icsk->icsk_ack.ato)
+ icsk->icsk_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_opt *tp = tcp_sk(sk);
+ tcp_dec_quickack_mode(sk, pkts);
+ inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
+}
- tcp_dec_quickack_mode(tp);
- tcp_clear_xmit_timer(sk, TCP_TIME_DACK);
+/* Determine a window scaling and initial window to offer.
+ * Based on the assumption that the given amount of space
+ * will be offered. Store the results in the tp structure.
+ * NOTE: for smooth operation initial space offering should
+ * be a multiple of mss if possible. We assume here that mss >= 1.
+ * This MUST be enforced by all callers.
+ */
+void tcp_select_initial_window(int __space, __u32 mss,
+ __u32 *rcv_wnd, __u32 *window_clamp,
+ int wscale_ok, __u8 *rcv_wscale)
+{
+ unsigned int space = (__space < 0 ? 0 : __space);
+
+ /* If no clamp set the clamp to the max possible scaled window */
+ if (*window_clamp == 0)
+ (*window_clamp) = (65535 << 14);
+ space = min(*window_clamp, space);
+
+ /* Quantize space offering to a multiple of mss if possible. */
+ if (space > mss)
+ space = (space / mss) * mss;
+
+ /* NOTE: offering an initial window larger than 32767
+ * will break some buggy TCP stacks. We try to be nice.
+ * If we are not window scaling, then this truncates
+ * our initial window offering to 32k. There should also
+ * be a sysctl option to stop being nice.
+ */
+ (*rcv_wnd) = min(space, MAX_TCP_WINDOW);
+ (*rcv_wscale) = 0;
+ if (wscale_ok) {
+ /* Set window scaling on max possible window
+ * See RFC1323 for an explanation of the limit to 14
+ */
+ space = max_t(u32, sysctl_tcp_rmem[2], sysctl_rmem_max);
+ while (space > 65535 && (*rcv_wscale) < 14) {
+ space >>= 1;
+ (*rcv_wscale)++;
+ }
+ }
+
+ /* Set initial window to value enough for senders,
+ * following RFC2414. Senders, not following this RFC,
+ * will be satisfied with 2.
+ */
+ if (mss > (1<<*rcv_wscale)) {
+ int init_cwnd = 4;
+ if (mss > 1460*3)
+ init_cwnd = 2;
+ else if (mss > 1460)
+ init_cwnd = 3;
+ if (*rcv_wnd > init_cwnd*mss)
+ *rcv_wnd = init_cwnd*mss;
+ }
+
+ /* Set the clamp no higher than max representable value */
+ (*window_clamp) = min(65535U << (*rcv_wscale), *window_clamp);
}
-/* Chose a new window to advertise, update state in tcp_opt for the
+/* Chose a new window to advertise, update state in tcp_sock for the
* socket, and return result with RFC1323 scaling applied. The return
* value can be stuffed directly into th->window for an outgoing
* frame.
*/
-static __inline__ u16 tcp_select_window(struct sock *sk)
+static u16 tcp_select_window(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
u32 cur_win = tcp_receive_window(tp);
u32 new_win = __tcp_select_window(sk);
tp->rcv_wnd = new_win;
tp->rcv_wup = tp->rcv_nxt;
+ /* Make sure we do not exceed the maximum possible
+ * scaled window.
+ */
+ if (!tp->rx_opt.rcv_wscale)
+ new_win = min(new_win, MAX_TCP_WINDOW);
+ else
+ new_win = min(new_win, (65535U << tp->rx_opt.rcv_wscale));
+
/* RFC1323 scaling applied */
- new_win >>= tp->rcv_wscale;
+ new_win >>= tp->rx_opt.rcv_wscale;
/* If we advertise zero window, disable fast path. */
if (new_win == 0)
return new_win;
}
+static void tcp_build_and_update_options(__u32 *ptr, struct tcp_sock *tp,
+ __u32 tstamp)
+{
+ if (tp->rx_opt.tstamp_ok) {
+ *ptr++ = __constant_htonl((TCPOPT_NOP << 24) |
+ (TCPOPT_NOP << 16) |
+ (TCPOPT_TIMESTAMP << 8) |
+ TCPOLEN_TIMESTAMP);
+ *ptr++ = htonl(tstamp);
+ *ptr++ = htonl(tp->rx_opt.ts_recent);
+ }
+ if (tp->rx_opt.eff_sacks) {
+ struct tcp_sack_block *sp = tp->rx_opt.dsack ? tp->duplicate_sack : tp->selective_acks;
+ int this_sack;
+
+ *ptr++ = htonl((TCPOPT_NOP << 24) |
+ (TCPOPT_NOP << 16) |
+ (TCPOPT_SACK << 8) |
+ (TCPOLEN_SACK_BASE + (tp->rx_opt.eff_sacks *
+ TCPOLEN_SACK_PERBLOCK)));
+ for(this_sack = 0; this_sack < tp->rx_opt.eff_sacks; this_sack++) {
+ *ptr++ = htonl(sp[this_sack].start_seq);
+ *ptr++ = htonl(sp[this_sack].end_seq);
+ }
+ if (tp->rx_opt.dsack) {
+ tp->rx_opt.dsack = 0;
+ tp->rx_opt.eff_sacks--;
+ }
+ }
+}
+
+/* Construct a tcp options header for a SYN or SYN_ACK packet.
+ * If this is every changed make sure to change the definition of
+ * MAX_SYN_SIZE to match the new maximum number of options that you
+ * can generate.
+ */
+static void tcp_syn_build_options(__u32 *ptr, int mss, int ts, int sack,
+ int offer_wscale, int wscale, __u32 tstamp,
+ __u32 ts_recent)
+{
+ /* We always get an MSS option.
+ * The option bytes which will be seen in normal data
+ * packets should timestamps be used, must be in the MSS
+ * advertised. But we subtract them from tp->mss_cache so
+ * that calculations in tcp_sendmsg are simpler etc.
+ * So account for this fact here if necessary. If we
+ * don't do this correctly, as a receiver we won't
+ * recognize data packets as being full sized when we
+ * should, and thus we won't abide by the delayed ACK
+ * rules correctly.
+ * SACKs don't matter, we never delay an ACK when we
+ * have any of those going out.
+ */
+ *ptr++ = htonl((TCPOPT_MSS << 24) | (TCPOLEN_MSS << 16) | mss);
+ if (ts) {
+ if(sack)
+ *ptr++ = __constant_htonl((TCPOPT_SACK_PERM << 24) | (TCPOLEN_SACK_PERM << 16) |
+ (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
+ else
+ *ptr++ = __constant_htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
+ (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
+ *ptr++ = htonl(tstamp); /* TSVAL */
+ *ptr++ = htonl(ts_recent); /* TSECR */
+ } else if(sack)
+ *ptr++ = __constant_htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
+ (TCPOPT_SACK_PERM << 8) | TCPOLEN_SACK_PERM);
+ if (offer_wscale)
+ *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_WINDOW << 16) | (TCPOLEN_WINDOW << 8) | (wscale));
+}
/* This routine actually transmits TCP packets queued in by
* tcp_do_sendmsg(). This is used by both the initial
* We are working here with either a clone of the original
* SKB, or a fresh unique copy made by the retransmit engine.
*/
-int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb)
+static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it, gfp_t gfp_mask)
{
- if(skb != NULL) {
- struct inet_opt *inet = inet_sk(sk);
- struct tcp_opt *tp = tcp_sk(sk);
- struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
- int tcp_header_size = tp->tcp_header_len;
- struct tcphdr *th;
- int sysctl_flags;
- int err;
+ const struct inet_connection_sock *icsk = inet_csk(sk);
+ struct inet_sock *inet;
+ struct tcp_sock *tp;
+ struct tcp_skb_cb *tcb;
+ int tcp_header_size;
+ struct tcphdr *th;
+ int sysctl_flags;
+ int err;
+
+ BUG_ON(!skb || !tcp_skb_pcount(skb));
+
+ /* If congestion control is doing timestamping, we must
+ * take such a timestamp before we potentially clone/copy.
+ */
+ if (icsk->icsk_ca_ops->rtt_sample)
+ __net_timestamp(skb);
+
+ if (likely(clone_it)) {
+ if (unlikely(skb_cloned(skb)))
+ skb = pskb_copy(skb, gfp_mask);
+ else
+ skb = skb_clone(skb, gfp_mask);
+ if (unlikely(!skb))
+ return -ENOBUFS;
+ }
+
+ inet = inet_sk(sk);
+ tp = tcp_sk(sk);
+ tcb = TCP_SKB_CB(skb);
+ tcp_header_size = tp->tcp_header_len;
#define SYSCTL_FLAG_TSTAMPS 0x1
#define SYSCTL_FLAG_WSCALE 0x2
#define SYSCTL_FLAG_SACK 0x4
- sysctl_flags = 0;
- if (tcb->flags & TCPCB_FLAG_SYN) {
- tcp_header_size = sizeof(struct tcphdr) + TCPOLEN_MSS;
- if(sysctl_tcp_timestamps) {
- tcp_header_size += TCPOLEN_TSTAMP_ALIGNED;
- sysctl_flags |= SYSCTL_FLAG_TSTAMPS;
- }
- if(sysctl_tcp_window_scaling) {
- tcp_header_size += TCPOLEN_WSCALE_ALIGNED;
- sysctl_flags |= SYSCTL_FLAG_WSCALE;
- }
- if(sysctl_tcp_sack) {
- sysctl_flags |= SYSCTL_FLAG_SACK;
- if(!(sysctl_flags & SYSCTL_FLAG_TSTAMPS))
- tcp_header_size += TCPOLEN_SACKPERM_ALIGNED;
- }
- } else if (tp->eff_sacks) {
- /* A SACK is 2 pad bytes, a 2 byte header, plus
- * 2 32-bit sequence numbers for each SACK block.
- */
- tcp_header_size += (TCPOLEN_SACK_BASE_ALIGNED +
- (tp->eff_sacks * TCPOLEN_SACK_PERBLOCK));
+ sysctl_flags = 0;
+ if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) {
+ tcp_header_size = sizeof(struct tcphdr) + TCPOLEN_MSS;
+ if(sysctl_tcp_timestamps) {
+ tcp_header_size += TCPOLEN_TSTAMP_ALIGNED;
+ sysctl_flags |= SYSCTL_FLAG_TSTAMPS;
+ }
+ if (sysctl_tcp_window_scaling) {
+ tcp_header_size += TCPOLEN_WSCALE_ALIGNED;
+ sysctl_flags |= SYSCTL_FLAG_WSCALE;
+ }
+ if (sysctl_tcp_sack) {
+ sysctl_flags |= SYSCTL_FLAG_SACK;
+ if (!(sysctl_flags & SYSCTL_FLAG_TSTAMPS))
+ tcp_header_size += TCPOLEN_SACKPERM_ALIGNED;
}
+ } else if (unlikely(tp->rx_opt.eff_sacks)) {
+ /* A SACK is 2 pad bytes, a 2 byte header, plus
+ * 2 32-bit sequence numbers for each SACK block.
+ */
+ tcp_header_size += (TCPOLEN_SACK_BASE_ALIGNED +
+ (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_packets_in_flight(tp) == 0)
+ tcp_ca_event(sk, CA_EVENT_TX_START);
+
+ th = (struct tcphdr *) skb_push(skb, tcp_header_size);
+ skb->h.th = th;
+ skb_set_owner_w(skb, sk);
+
+ /* Build TCP header and checksum it. */
+ th->source = inet->sport;
+ th->dest = inet->dport;
+ th->seq = htonl(tcb->seq);
+ th->ack_seq = htonl(tp->rcv_nxt);
+ *(((__u16 *)th) + 6) = htons(((tcp_header_size >> 2) << 12) |
+ tcb->flags);
+
+ if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) {
+ /* RFC1323: The window in SYN & SYN/ACK segments
+ * is never scaled.
*/
- if (tcp_is_vegas(tp) && tcp_packets_in_flight(tp) == 0)
- tcp_vegas_enable(tp);
-
- th = (struct tcphdr *) skb_push(skb, tcp_header_size);
- skb->h.th = th;
- skb_set_owner_w(skb, sk);
-
- /* Build TCP header and checksum it. */
- th->source = inet->sport;
- th->dest = inet->dport;
- th->seq = htonl(tcb->seq);
- th->ack_seq = htonl(tp->rcv_nxt);
- *(((__u16 *)th) + 6) = htons(((tcp_header_size >> 2) << 12) | tcb->flags);
- if (tcb->flags & TCPCB_FLAG_SYN) {
- /* RFC1323: The window in SYN & SYN/ACK segments
- * is never scaled.
- */
- th->window = htons(tp->rcv_wnd);
- } else {
- th->window = htons(tcp_select_window(sk));
- }
- th->check = 0;
- th->urg_ptr = 0;
+ th->window = htons(tp->rcv_wnd);
+ } else {
+ th->window = htons(tcp_select_window(sk));
+ }
+ th->check = 0;
+ th->urg_ptr = 0;
- if (tp->urg_mode &&
- between(tp->snd_up, tcb->seq+1, tcb->seq+0xFFFF)) {
- th->urg_ptr = htons(tp->snd_up-tcb->seq);
- th->urg = 1;
- }
+ if (unlikely(tp->urg_mode &&
+ between(tp->snd_up, tcb->seq+1, tcb->seq+0xFFFF))) {
+ th->urg_ptr = htons(tp->snd_up-tcb->seq);
+ th->urg = 1;
+ }
- if (tcb->flags & TCPCB_FLAG_SYN) {
- tcp_syn_build_options((__u32 *)(th + 1),
- tcp_advertise_mss(sk),
- (sysctl_flags & SYSCTL_FLAG_TSTAMPS),
- (sysctl_flags & SYSCTL_FLAG_SACK),
- (sysctl_flags & SYSCTL_FLAG_WSCALE),
- tp->rcv_wscale,
- tcb->when,
- tp->ts_recent);
- } else {
- tcp_build_and_update_options((__u32 *)(th + 1),
- tp, tcb->when);
+ if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) {
+ tcp_syn_build_options((__u32 *)(th + 1),
+ tcp_advertise_mss(sk),
+ (sysctl_flags & SYSCTL_FLAG_TSTAMPS),
+ (sysctl_flags & SYSCTL_FLAG_SACK),
+ (sysctl_flags & SYSCTL_FLAG_WSCALE),
+ tp->rx_opt.rcv_wscale,
+ tcb->when,
+ tp->rx_opt.ts_recent);
+ } else {
+ tcp_build_and_update_options((__u32 *)(th + 1),
+ tp, tcb->when);
+ TCP_ECN_send(sk, tp, skb, tcp_header_size);
+ }
- TCP_ECN_send(sk, tp, skb, tcp_header_size);
- }
- tp->af_specific->send_check(sk, th, skb->len, skb);
+ icsk->icsk_af_ops->send_check(sk, skb->len, skb);
- if (tcb->flags & TCPCB_FLAG_ACK)
- tcp_event_ack_sent(sk);
+ if (likely(tcb->flags & TCPCB_FLAG_ACK))
+ tcp_event_ack_sent(sk, tcp_skb_pcount(skb));
- if (skb->len != tcp_header_size)
- tcp_event_data_sent(tp, skb, sk);
+ if (skb->len != tcp_header_size)
+ tcp_event_data_sent(tp, skb, sk);
- TCP_INC_STATS(TcpOutSegs);
+ TCP_INC_STATS(TCP_MIB_OUTSEGS);
- err = tp->af_specific->queue_xmit(skb, 0);
- if (err <= 0)
- return err;
+ err = icsk->icsk_af_ops->queue_xmit(skb, 0);
+ if (unlikely(err <= 0))
+ return err;
- tcp_enter_cwr(tp);
+ tcp_enter_cwr(sk);
+
+ /* NET_XMIT_CN is special. It does not guarantee,
+ * that this packet is lost. It tells that device
+ * is about to start to drop packets or already
+ * drops some packets of the same priority and
+ * invokes us to send less aggressively.
+ */
+ return err == NET_XMIT_CN ? 0 : err;
- /* NET_XMIT_CN is special. It does not guarantee,
- * that this packet is lost. It tells that device
- * is about to start to drop packets or already
- * drops some packets of the same priority and
- * invokes us to send less aggressively.
- */
- return err == NET_XMIT_CN ? 0 : err;
- }
- return -ENOBUFS;
#undef SYSCTL_FLAG_TSTAMPS
#undef SYSCTL_FLAG_WSCALE
#undef SYSCTL_FLAG_SACK
*/
static void tcp_queue_skb(struct sock *sk, struct sk_buff *skb)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
/* Advance write_seq and place onto the write_queue. */
tp->write_seq = TCP_SKB_CB(skb)->end_seq;
+ skb_header_release(skb);
__skb_queue_tail(&sk->sk_write_queue, skb);
sk_charge_skb(sk, skb);
/* Queue it, remembering where we must start sending. */
- if (tp->send_head == NULL)
- tp->send_head = skb;
-}
-
-/* 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)
-{
- struct tcp_opt *tp = tcp_sk(sk);
- struct sk_buff *skb = tp->send_head;
-
- if (tcp_snd_test(tp, skb, cur_mss, TCP_NAGLE_PUSH)) {
- /* Send it out now. */
- TCP_SKB_CB(skb)->when = tcp_time_stamp;
- if (!tcp_transmit_skb(sk, skb_clone(skb, sk->sk_allocation))) {
- tp->send_head = NULL;
- tp->snd_nxt = TCP_SKB_CB(skb)->end_seq;
- if (tp->packets_out++ == 0)
- tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
- return;
- }
- }
+ if (sk->sk_send_head == NULL)
+ sk->sk_send_head = skb;
}
-/* Split fragmented skb to two parts at length len. */
-
-static void skb_split(struct sk_buff *skb, struct sk_buff *skb1, u32 len)
+static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned int mss_now)
{
- int i;
- int pos = skb_headlen(skb);
-
- if (len < pos) {
- /* Split line is inside header. */
- memcpy(skb_put(skb1, pos-len), skb->data + len, pos-len);
-
- /* And move data appendix as is. */
- for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
- skb_shinfo(skb1)->frags[i] = skb_shinfo(skb)->frags[i];
-
- skb_shinfo(skb1)->nr_frags = skb_shinfo(skb)->nr_frags;
- skb_shinfo(skb)->nr_frags = 0;
-
- skb1->data_len = skb->data_len;
- skb1->len += skb1->data_len;
- skb->data_len = 0;
- skb->len = len;
- skb->tail = skb->data+len;
+ if (skb->len <= mss_now ||
+ !(sk->sk_route_caps & NETIF_F_TSO)) {
+ /* Avoid the costly divide in the normal
+ * non-TSO case.
+ */
+ skb_shinfo(skb)->tso_segs = 1;
+ skb_shinfo(skb)->tso_size = 0;
} else {
- int k = 0;
- int nfrags = skb_shinfo(skb)->nr_frags;
-
- /* Second chunk has no header, nothing to copy. */
-
- skb_shinfo(skb)->nr_frags = 0;
- skb1->len = skb1->data_len = skb->len - len;
- skb->len = len;
- skb->data_len = len - pos;
-
- for (i=0; i<nfrags; i++) {
- int size = skb_shinfo(skb)->frags[i].size;
- if (pos + size > len) {
- skb_shinfo(skb1)->frags[k] = skb_shinfo(skb)->frags[i];
-
- if (pos < len) {
- /* Split frag.
- * We have to variants in this case:
- * 1. Move all the frag to the second
- * part, if it is possible. F.e.
- * this approach is mandatory for TUX,
- * where splitting is expensive.
- * 2. Split is accurately. We make this.
- */
- get_page(skb_shinfo(skb)->frags[i].page);
- skb_shinfo(skb1)->frags[0].page_offset += (len-pos);
- skb_shinfo(skb1)->frags[0].size -= (len-pos);
- skb_shinfo(skb)->frags[i].size = len-pos;
- skb_shinfo(skb)->nr_frags++;
- }
- k++;
- } else {
- skb_shinfo(skb)->nr_frags++;
- }
- pos += size;
- }
- skb_shinfo(skb1)->nr_frags = k;
+ unsigned int factor;
+
+ factor = skb->len + (mss_now - 1);
+ factor /= mss_now;
+ skb_shinfo(skb)->tso_segs = factor;
+ 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)
+int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss_now)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *buff;
- int nsize = skb->len - len;
+ int nsize, old_factor;
u16 flags;
+ BUG_ON(len > skb->len);
+
+ clear_all_retrans_hints(tp);
+ nsize = skb_headlen(skb) - len;
+ if (nsize < 0)
+ nsize = 0;
+
if (skb_cloned(skb) &&
skb_is_nonlinear(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
return -ENOMEM;
/* Get a new skb... force flag on. */
- buff = tcp_alloc_skb(sk, nsize, GFP_ATOMIC);
+ buff = sk_stream_alloc_skb(sk, nsize, GFP_ATOMIC);
if (buff == NULL)
return -ENOMEM; /* We'll just try again later. */
- sk_charge_skb(sk, buff);
+
+ buff->truesize = skb->len - len;
+ skb->truesize -= buff->truesize;
/* Correct the sequence numbers. */
TCP_SKB_CB(buff)->seq = TCP_SKB_CB(skb)->seq + len;
flags = TCP_SKB_CB(skb)->flags;
TCP_SKB_CB(skb)->flags = flags & ~(TCPCB_FLAG_FIN|TCPCB_FLAG_PSH);
TCP_SKB_CB(buff)->flags = flags;
- TCP_SKB_CB(buff)->sacked = TCP_SKB_CB(skb)->sacked&(TCPCB_LOST|TCPCB_EVER_RETRANS|TCPCB_AT_TAIL);
- if (TCP_SKB_CB(buff)->sacked&TCPCB_LOST) {
- tp->lost_out++;
- tp->left_out++;
- }
+ TCP_SKB_CB(buff)->sacked = TCP_SKB_CB(skb)->sacked;
TCP_SKB_CB(skb)->sacked &= ~TCPCB_AT_TAIL;
if (!skb_shinfo(skb)->nr_frags && skb->ip_summed != CHECKSUM_HW) {
* skbs, which it never sent before. --ANK
*/
TCP_SKB_CB(buff)->when = TCP_SKB_CB(skb)->when;
+ buff->tstamp = skb->tstamp;
+
+ old_factor = tcp_skb_pcount(skb);
+
+ /* 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);
+
+ /* If this packet has been sent out already, we must
+ * adjust the various packet counters.
+ */
+ if (!before(tp->snd_nxt, TCP_SKB_CB(buff)->end_seq)) {
+ int diff = old_factor - tcp_skb_pcount(skb) -
+ tcp_skb_pcount(buff);
+
+ tp->packets_out -= diff;
+
+ if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)
+ tp->sacked_out -= diff;
+ if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS)
+ tp->retrans_out -= diff;
+
+ if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST) {
+ tp->lost_out -= diff;
+ tp->left_out -= diff;
+ }
+
+ if (diff > 0) {
+ /* Adjust Reno SACK estimate. */
+ if (!tp->rx_opt.sack_ok) {
+ tp->sacked_out -= diff;
+ if ((int)tp->sacked_out < 0)
+ tp->sacked_out = 0;
+ tcp_sync_left_out(tp);
+ }
+
+ tp->fackets_out -= diff;
+ if ((int)tp->fackets_out < 0)
+ tp->fackets_out = 0;
+ }
+ }
/* Link BUFF into the send queue. */
- __skb_append(skb, buff);
+ skb_header_release(buff);
+ __skb_append(skb, buff, &sk->sk_write_queue);
return 0;
}
* eventually). The difference is that pulled data not copied, but
* immediately discarded.
*/
-unsigned char * __pskb_trim_head(struct sk_buff *skb, int len)
+static unsigned char *__pskb_trim_head(struct sk_buff *skb, int len)
{
int i, k, eat;
return skb->tail;
}
-static int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len)
+int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len)
{
if (skb_cloned(skb) &&
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
TCP_SKB_CB(skb)->seq += len;
skb->ip_summed = CHECKSUM_HW;
+
+ skb->truesize -= len;
+ sk->sk_wmem_queued -= len;
+ sk->sk_forward_alloc += len;
+ sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
+
+ /* Any change of skb->len requires recalculation of tso
+ * factor and mss.
+ */
+ if (tcp_skb_pcount(skb) > 1)
+ tcp_set_skb_tso_segs(sk, skb, tcp_current_mss(sk, 1));
+
return 0;
}
/* This function synchronize snd mss to current pmtu/exthdr set.
- tp->user_mss is mss set by user by TCP_MAXSEG. It does NOT counts
+ tp->rx_opt.user_mss is mss set by user by TCP_MAXSEG. It does NOT counts
for TCP options, but includes only bare TCP header.
- tp->mss_clamp is mss negotiated at connection setup.
- It is minumum of user_mss and mss received with SYN.
+ tp->rx_opt.mss_clamp is mss negotiated at connection setup.
+ It is minimum of user_mss and mss received with SYN.
It also does not include TCP options.
- tp->pmtu_cookie is last pmtu, seen by this function.
+ inet_csk(sk)->icsk_pmtu_cookie is last pmtu, seen by this function.
tp->mss_cache is current effective sending mss, including
all tcp options except for SACKs. It is evaluated,
taking into account current pmtu, but never exceeds
- tp->mss_clamp.
+ tp->rx_opt.mss_clamp.
NOTE1. rfc1122 clearly states that advertised MSS
DOES NOT include either tcp or ip options.
- NOTE2. tp->pmtu_cookie and tp->mss_cache are READ ONLY outside
- this function. --ANK (980731)
+ NOTE2. inet_csk(sk)->icsk_pmtu_cookie and tp->mss_cache
+ are READ ONLY outside this function. --ANK (980731)
*/
-int tcp_sync_mss(struct sock *sk, u32 pmtu)
+unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu)
{
- struct tcp_opt *tp = tcp_sk(sk);
- struct dst_entry *dst = __sk_dst_get(sk);
- int mss_now;
-
- if (dst && dst->ops->get_mss)
- pmtu = dst->ops->get_mss(dst, pmtu);
-
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
/* Calculate base mss without TCP options:
It is MMS_S - sizeof(tcphdr) of rfc1122
*/
- mss_now = pmtu - tp->af_specific->net_header_len - sizeof(struct tcphdr);
+ int mss_now = (pmtu - icsk->icsk_af_ops->net_header_len -
+ sizeof(struct tcphdr));
/* Clamp it (mss_clamp does not include tcp options) */
- if (mss_now > tp->mss_clamp)
- mss_now = tp->mss_clamp;
+ if (mss_now > tp->rx_opt.mss_clamp)
+ mss_now = tp->rx_opt.mss_clamp;
/* Now subtract optional transport overhead */
- mss_now -= tp->ext_header_len + tp->ext2_header_len;
+ mss_now -= icsk->icsk_ext_hdr_len;
/* Then reserve room for full set of TCP options and 8 bytes of data */
if (mss_now < 48)
mss_now = max((tp->max_window>>1), 68U - tp->tcp_header_len);
/* And store cached results */
- tp->pmtu_cookie = pmtu;
- tp->mss_cache = tp->mss_cache_std = mss_now;
+ icsk->icsk_pmtu_cookie = pmtu;
+ tp->mss_cache = mss_now;
+
+ return mss_now;
+}
+
+/* Compute the current effective MSS, taking SACKs and IP options,
+ * and even PMTU discovery events into account.
+ *
+ * LARGESEND note: !urg_mode is overkill, only frames up to snd_up
+ * 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_allowed)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct dst_entry *dst = __sk_dst_get(sk);
+ u32 mss_now;
+ u16 xmit_size_goal;
+ int doing_tso = 0;
+
+ mss_now = tp->mss_cache;
- if (sk->sk_route_caps & NETIF_F_TSO) {
- int large_mss;
+ if (large_allowed &&
+ (sk->sk_route_caps & NETIF_F_TSO) &&
+ !tp->urg_mode)
+ doing_tso = 1;
- large_mss = 65535 - tp->af_specific->net_header_len -
- tp->ext_header_len - tp->ext2_header_len - tp->tcp_header_len;
+ if (dst) {
+ u32 mtu = dst_mtu(dst);
+ if (mtu != inet_csk(sk)->icsk_pmtu_cookie)
+ mss_now = tcp_sync_mss(sk, mtu);
+ }
+
+ if (tp->rx_opt.eff_sacks)
+ mss_now -= (TCPOLEN_SACK_BASE_ALIGNED +
+ (tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK));
+
+ xmit_size_goal = mss_now;
- if (tp->max_window && large_mss > (tp->max_window>>1))
- large_mss = max((tp->max_window>>1), 68U - tp->tcp_header_len);
+ if (doing_tso) {
+ xmit_size_goal = (65535 -
+ inet_csk(sk)->icsk_af_ops->net_header_len -
+ inet_csk(sk)->icsk_ext_hdr_len -
+ tp->tcp_header_len);
- /* Always keep large mss multiple of real mss. */
- tp->mss_cache = mss_now*(large_mss/mss_now);
+ if (tp->max_window &&
+ (xmit_size_goal > (tp->max_window >> 1)))
+ xmit_size_goal = max((tp->max_window >> 1),
+ 68U - tp->tcp_header_len);
+
+ xmit_size_goal -= (xmit_size_goal % mss_now);
}
+ tp->xmit_size_goal = xmit_size_goal;
return mss_now;
}
+/* Congestion window validation. (RFC2861) */
+
+static 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) >= inet_csk(sk)->icsk_rto)
+ tcp_cwnd_application_limited(sk);
+ }
+}
+
+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 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. */
+ if (skb->len != skb->data_len)
+ return tcp_fragment(sk, skb, len, mss_now);
+
+ 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, &sk->sk_write_queue);
+
+ 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)
+{
+ const struct inet_connection_sock *icsk = inet_csk(sk);
+ u32 send_win, cong_win, limit, in_flight;
+
+ if (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN)
+ return 0;
+
+ if (icsk->icsk_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 a full-sized TSO skb can be sent, do it. */
+ if (limit >= 65536)
+ 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
* send_head. This happens as incoming acks open up the remote
* 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_opt *tp = tcp_sk(sk);
- unsigned int mss_now;
+ struct tcp_sock *tp = tcp_sk(sk);
+ 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;
- /* 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);
+ sent_pkts = 0;
+ while ((skb = sk->sk_send_head)) {
+ unsigned int limit;
- while((skb = tp->send_head) &&
- tcp_snd_test(tp, 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))
- break;
- }
+ tso_segs = tcp_init_tso_segs(sk, skb, mss_now);
+ BUG_ON(!tso_segs);
- TCP_SKB_CB(skb)->when = tcp_time_stamp;
- if (tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)))
+ cwnd_quota = tcp_cwnd_test(tp, skb);
+ if (!cwnd_quota)
+ break;
+
+ if (unlikely(!tcp_snd_wnd_test(tp, skb, mss_now)))
+ break;
+
+ 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;
- /* Advance the send_head. This one is sent out. */
- update_send_head(sk, tp, skb);
- tcp_minshall_update(tp, mss_now, skb);
- sent_pkts = 1;
}
- if (sent_pkts) {
- tcp_cwnd_validate(sk, tp);
- return 0;
+ limit = mss_now;
+ if (tso_segs > 1) {
+ 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;
+ }
}
- return !tp->packets_out && tp->send_head;
+ if (skb->len > limit &&
+ unlikely(tso_fragment(sk, skb, limit, mss_now)))
+ break;
+
+ TCP_SKB_CB(skb)->when = tcp_time_stamp;
+
+ if (unlikely(tcp_transmit_skb(sk, skb, 1, 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++;
+ }
+
+ if (likely(sent_pkts)) {
+ tcp_cwnd_validate(sk, tp);
+ return 0;
+ }
+ 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;
+
+ 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)) {
+ unsigned int limit;
+
+ BUG_ON(!tso_segs);
+
+ limit = mss_now;
+ if (tso_segs > 1) {
+ 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 &&
+ unlikely(tso_fragment(sk, skb, limit, mss_now)))
+ return;
+
+ /* Send it out now. */
+ TCP_SKB_CB(skb)->when = tcp_time_stamp;
+
+ if (likely(!tcp_transmit_skb(sk, skb, 1, sk->sk_allocation))) {
+ update_send_head(sk, tp, skb);
+ tcp_cwnd_validate(sk, tp);
+ return;
+ }
}
- return 0;
}
/* This function returns the amount that we can raise the
*/
u32 __tcp_select_window(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
- /* MSS for the peer's data. Previous verions used mss_clamp
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
+ /* MSS for the peer's data. Previous versions used mss_clamp
* here. I don't know if the value based on our guesses
* of peer's MSS is better for the performance. It's more correct
* but may be worse for the performance because of rcv_mss
* fluctuations. --SAW 1998/11/1
*/
- int mss = tp->ack.rcv_mss;
+ int mss = icsk->icsk_ack.rcv_mss;
int free_space = tcp_space(sk);
int full_space = min_t(int, tp->window_clamp, tcp_full_space(sk));
int window;
mss = full_space;
if (free_space < full_space/2) {
- tp->ack.quick = 0;
+ icsk->icsk_ack.quick = 0;
if (tcp_memory_pressure)
tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U*tp->advmss);
if (free_space > tp->rcv_ssthresh)
free_space = tp->rcv_ssthresh;
- /* Get the largest window that is a nice multiple of mss.
- * Window clamp already applied above.
- * If our current window offering is within 1 mss of the
- * free space we just keep it. This prevents the divide
- * and multiply from happening most of the time.
- * We also don't do any window rounding when the free space
- * is too small.
+ /* Don't do rounding if we are using window scaling, since the
+ * scaled window will not line up with the MSS boundary anyway.
*/
window = tp->rcv_wnd;
- if (window <= free_space - mss || window > free_space)
- window = (free_space/mss)*mss;
+ if (tp->rx_opt.rcv_wscale) {
+ window = free_space;
+
+ /* Advertise enough space so that it won't get scaled away.
+ * Import case: prevent zero window announcement if
+ * 1<<rcv_wscale > mss.
+ */
+ if (((window >> tp->rx_opt.rcv_wscale) << tp->rx_opt.rcv_wscale) != window)
+ window = (((window >> tp->rx_opt.rcv_wscale) + 1)
+ << tp->rx_opt.rcv_wscale);
+ } else {
+ /* Get the largest window that is a nice multiple of mss.
+ * Window clamp already applied above.
+ * If our current window offering is within 1 mss of the
+ * free space we just keep it. This prevents the divide
+ * and multiply from happening most of the time.
+ * We also don't do any window rounding when the free space
+ * is too small.
+ */
+ if (window <= free_space - mss || window > free_space)
+ window = (free_space/mss)*mss;
+ }
return window;
}
/* Attempt to collapse two adjacent SKB's during retransmission. */
static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int mss_now)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *next_skb = skb->next;
/* The first test we must make is that neither of these two
* SKB's are still referenced by someone else.
*/
- if(!skb_cloned(skb) && !skb_cloned(next_skb)) {
+ if (!skb_cloned(skb) && !skb_cloned(next_skb)) {
int skb_size = skb->len, next_skb_size = next_skb->len;
u16 flags = TCP_SKB_CB(skb)->flags;
((skb_size + next_skb_size) > mss_now))
return;
- /* Ok. We will be able to collapse the packet. */
- __skb_unlink(next_skb, next_skb->list);
+ BUG_ON(tcp_skb_pcount(skb) != 1 ||
+ tcp_skb_pcount(next_skb) != 1);
+
+ /* changing transmit queue under us so clear hints */
+ clear_all_retrans_hints(tp);
+
+ /* Ok. We will be able to collapse the packet. */
+ __skb_unlink(next_skb, &sk->sk_write_queue);
memcpy(skb_put(skb, next_skb_size), next_skb->data, next_skb_size);
*/
TCP_SKB_CB(skb)->sacked |= TCP_SKB_CB(next_skb)->sacked&(TCPCB_EVER_RETRANS|TCPCB_AT_TAIL);
if (TCP_SKB_CB(next_skb)->sacked&TCPCB_SACKED_RETRANS)
- tp->retrans_out--;
+ tp->retrans_out -= tcp_skb_pcount(next_skb);
if (TCP_SKB_CB(next_skb)->sacked&TCPCB_LOST) {
- tp->lost_out--;
- tp->left_out--;
+ tp->lost_out -= tcp_skb_pcount(next_skb);
+ tp->left_out -= tcp_skb_pcount(next_skb);
}
/* Reno case is special. Sigh... */
- if (!tp->sack_ok && tp->sacked_out) {
- tp->sacked_out--;
- tp->left_out--;
+ if (!tp->rx_opt.sack_ok && tp->sacked_out) {
+ tcp_dec_pcount_approx(&tp->sacked_out, next_skb);
+ tp->left_out -= tcp_skb_pcount(next_skb);
}
/* Not quite right: it can be > snd.fack, but
* it is better to underestimate fackets.
*/
- if (tp->fackets_out)
- tp->fackets_out--;
- tcp_free_skb(sk, next_skb);
- tp->packets_out--;
+ tcp_dec_pcount_approx(&tp->fackets_out, next_skb);
+ tcp_packets_out_dec(tp, next_skb);
+ sk_stream_free_skb(sk, next_skb);
}
}
*/
void tcp_simple_retransmit(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ const struct inet_connection_sock *icsk = inet_csk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
unsigned int mss = tcp_current_mss(sk, 0);
int lost = 0;
- for_retrans_queue(skb, sk, tp) {
+ sk_stream_for_retrans_queue(skb, sk) {
if (skb->len > mss &&
!(TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_ACKED)) {
if (TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_RETRANS) {
TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
- tp->retrans_out--;
+ tp->retrans_out -= tcp_skb_pcount(skb);
}
if (!(TCP_SKB_CB(skb)->sacked&TCPCB_LOST)) {
TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
- tp->lost_out++;
+ tp->lost_out += tcp_skb_pcount(skb);
lost = 1;
}
}
}
+ clear_all_retrans_hints(tp);
+
if (!lost)
return;
* in network, but units changed and effective
* cwnd/ssthresh really reduced now.
*/
- if (tp->ca_state != TCP_CA_Loss) {
+ if (icsk->icsk_ca_state != TCP_CA_Loss) {
tp->high_seq = tp->snd_nxt;
- tp->snd_ssthresh = tcp_current_ssthresh(tp);
+ tp->snd_ssthresh = tcp_current_ssthresh(sk);
tp->prior_ssthresh = 0;
tp->undo_marker = 0;
- tcp_set_ca_state(tp, TCP_CA_Loss);
+ tcp_set_ca_state(sk, TCP_CA_Loss);
}
tcp_xmit_retransmit_queue(sk);
}
*/
int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
unsigned int cur_mss = tcp_current_mss(sk, 0);
int err;
/* Do not sent more than we queued. 1/4 is reserved for possible
- * copying overhead: frgagmentation, tunneling, mangling etc.
+ * copying overhead: fragmentation, tunneling, mangling etc.
*/
if (atomic_read(&sk->sk_wmem_alloc) >
min(sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2), sk->sk_sndbuf))
if (before(TCP_SKB_CB(skb)->seq, tp->snd_una)) {
if (before(TCP_SKB_CB(skb)->end_seq, tp->snd_una))
BUG();
-
- if (sk->sk_route_caps & NETIF_F_TSO) {
- sk->sk_route_caps &= ~NETIF_F_TSO;
- sk->sk_no_largesend = 1;
- tp->mss_cache = tp->mss_cache_std;
- }
-
if (tcp_trim_head(sk, skb, tp->snd_una - TCP_SKB_CB(skb)->seq))
return -ENOMEM;
}
&& TCP_SKB_CB(skb)->seq != tp->snd_una)
return -EAGAIN;
- if(skb->len > cur_mss) {
- if(tcp_fragment(sk, skb, cur_mss))
+ if (skb->len > cur_mss) {
+ if (tcp_fragment(sk, skb, cur_mss, cur_mss))
return -ENOMEM; /* We'll try again later. */
-
- /* New SKB created, account for it. */
- tp->packets_out++;
}
/* Collapse two adjacent packets if worthwhile and we can. */
if(!(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_SYN) &&
(skb->len < (cur_mss >> 1)) &&
- (skb->next != tp->send_head) &&
+ (skb->next != sk->sk_send_head) &&
(skb->next != (struct sk_buff *)&sk->sk_write_queue) &&
(skb_shinfo(skb)->nr_frags == 0 && skb_shinfo(skb->next)->nr_frags == 0) &&
+ (tcp_skb_pcount(skb) == 1 && tcp_skb_pcount(skb->next) == 1) &&
(sysctl_tcp_retrans_collapse != 0))
tcp_retrans_try_collapse(sk, skb, cur_mss);
- if(tp->af_specific->rebuild_header(sk))
+ if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk))
return -EHOSTUNREACH; /* Routing failure or similar. */
/* Some Solaris stacks overoptimize and ignore the FIN on a
tp->snd_una == (TCP_SKB_CB(skb)->end_seq - 1)) {
if (!pskb_trim(skb, 0)) {
TCP_SKB_CB(skb)->seq = TCP_SKB_CB(skb)->end_seq - 1;
+ skb_shinfo(skb)->tso_segs = 1;
+ skb_shinfo(skb)->tso_size = 0;
skb->ip_summed = CHECKSUM_NONE;
skb->csum = 0;
}
*/
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- err = tcp_transmit_skb(sk, (skb_cloned(skb) ?
- pskb_copy(skb, GFP_ATOMIC):
- skb_clone(skb, GFP_ATOMIC)));
+ err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
if (err == 0) {
/* Update global TCP statistics. */
- TCP_INC_STATS(TcpRetransSegs);
+ TCP_INC_STATS(TCP_MIB_RETRANSSEGS);
+
+ tp->total_retrans++;
#if FASTRETRANS_DEBUG > 0
if (TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_RETRANS) {
}
#endif
TCP_SKB_CB(skb)->sacked |= TCPCB_RETRANS;
- tp->retrans_out++;
+ tp->retrans_out += tcp_skb_pcount(skb);
/* Save stamp of the first retransmit. */
if (!tp->retrans_stamp)
*/
void tcp_xmit_retransmit_queue(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ const struct inet_connection_sock *icsk = inet_csk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
- int packet_cnt = tp->lost_out;
+ int packet_cnt;
+
+ if (tp->retransmit_skb_hint) {
+ skb = tp->retransmit_skb_hint;
+ packet_cnt = tp->retransmit_cnt_hint;
+ }else{
+ skb = sk->sk_write_queue.next;
+ packet_cnt = 0;
+ }
/* First pass: retransmit lost packets. */
- if (packet_cnt) {
- for_retrans_queue(skb, sk, tp) {
+ if (tp->lost_out) {
+ sk_stream_for_retrans_queue_from(skb, sk) {
__u8 sacked = TCP_SKB_CB(skb)->sacked;
+ /* we could do better than to assign each time */
+ tp->retransmit_skb_hint = skb;
+ tp->retransmit_cnt_hint = packet_cnt;
+
+ /* Assume this retransmit will generate
+ * only one packet for congestion window
+ * calculation purposes. This works because
+ * tcp_retransmit_skb() will chop up the
+ * packet to be MSS sized and all the
+ * packet counting works out.
+ */
if (tcp_packets_in_flight(tp) >= tp->snd_cwnd)
return;
- if (sacked&TCPCB_LOST) {
+ if (sacked & TCPCB_LOST) {
if (!(sacked&(TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS))) {
- if (tcp_retransmit_skb(sk, skb))
+ if (tcp_retransmit_skb(sk, skb)) {
+ tp->retransmit_skb_hint = NULL;
return;
- if (tp->ca_state != TCP_CA_Loss)
- NET_INC_STATS_BH(TCPFastRetrans);
+ }
+ if (icsk->icsk_ca_state != TCP_CA_Loss)
+ NET_INC_STATS_BH(LINUX_MIB_TCPFASTRETRANS);
else
- NET_INC_STATS_BH(TCPSlowStartRetrans);
+ NET_INC_STATS_BH(LINUX_MIB_TCPSLOWSTARTRETRANS);
if (skb ==
skb_peek(&sk->sk_write_queue))
- tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ inet_csk(sk)->icsk_rto,
+ TCP_RTO_MAX);
}
- if (--packet_cnt <= 0)
+ packet_cnt += tcp_skb_pcount(skb);
+ if (packet_cnt >= tp->lost_out)
break;
}
}
/* OK, demanded retransmission is finished. */
/* Forward retransmissions are possible only during Recovery. */
- if (tp->ca_state != TCP_CA_Recovery)
+ if (icsk->icsk_ca_state != TCP_CA_Recovery)
return;
/* No forward retransmissions in Reno are possible. */
- if (!tp->sack_ok)
+ if (!tp->rx_opt.sack_ok)
return;
/* Yeah, we have to make difficult choice between forward transmission
* and retransmission... Both ways have their merits...
*
- * For now we do not retrnamsit anything, while we have some new
+ * For now we do not retransmit anything, while we have some new
* segments to send.
*/
if (tcp_may_send_now(sk, tp))
return;
- packet_cnt = 0;
+ if (tp->forward_skb_hint) {
+ skb = tp->forward_skb_hint;
+ packet_cnt = tp->forward_cnt_hint;
+ } else{
+ skb = sk->sk_write_queue.next;
+ packet_cnt = 0;
+ }
+
+ sk_stream_for_retrans_queue_from(skb, sk) {
+ tp->forward_cnt_hint = packet_cnt;
+ tp->forward_skb_hint = skb;
- for_retrans_queue(skb, sk, tp) {
- if(++packet_cnt > tp->fackets_out)
+ /* Similar to the retransmit loop above we
+ * can pretend that the retransmitted SKB
+ * we send out here will be composed of one
+ * real MSS sized packet because tcp_retransmit_skb()
+ * will fragment it if necessary.
+ */
+ if (++packet_cnt > tp->fackets_out)
break;
if (tcp_packets_in_flight(tp) >= tp->snd_cwnd)
break;
- if(TCP_SKB_CB(skb)->sacked & TCPCB_TAGBITS)
+ if (TCP_SKB_CB(skb)->sacked & TCPCB_TAGBITS)
continue;
/* Ok, retransmit it. */
- if(tcp_retransmit_skb(sk, skb))
+ if (tcp_retransmit_skb(sk, skb)) {
+ tp->forward_skb_hint = NULL;
break;
+ }
if (skb == skb_peek(&sk->sk_write_queue))
- tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ inet_csk(sk)->icsk_rto,
+ TCP_RTO_MAX);
- NET_INC_STATS_BH(TCPForwardRetrans);
+ NET_INC_STATS_BH(LINUX_MIB_TCPFORWARDRETRANS);
}
}
*/
void tcp_send_fin(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb = skb_peek_tail(&sk->sk_write_queue);
- unsigned int mss_now;
+ int mss_now;
/* Optimization, tack on the FIN if we have a queue of
* unsent frames. But be careful about outgoing SACKS
* and IP options.
*/
- mss_now = tcp_current_mss(sk, 1);
+ mss_now = tcp_current_mss(sk, 1);
- if(tp->send_head != NULL) {
+ if (sk->sk_send_head != NULL) {
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_FIN;
TCP_SKB_CB(skb)->end_seq++;
tp->write_seq++;
} else {
/* Socket is locked, keep trying until memory is available. */
for (;;) {
- skb = alloc_skb(MAX_TCP_HEADER, GFP_KERNEL);
+ skb = alloc_skb_fclone(MAX_TCP_HEADER, GFP_KERNEL);
if (skb)
break;
yield();
skb->csum = 0;
TCP_SKB_CB(skb)->flags = (TCPCB_FLAG_ACK | TCPCB_FLAG_FIN);
TCP_SKB_CB(skb)->sacked = 0;
+ skb_shinfo(skb)->tso_segs = 1;
+ skb_shinfo(skb)->tso_size = 0;
/* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */
TCP_SKB_CB(skb)->seq = tp->write_seq;
* 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, gfp_t priority)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
/* NOTE: No TCP options attached and we never retransmit this. */
skb = alloc_skb(MAX_TCP_HEADER, priority);
if (!skb) {
- NET_INC_STATS(TCPAbortFailed);
+ NET_INC_STATS(LINUX_MIB_TCPABORTFAILED);
return;
}
skb->csum = 0;
TCP_SKB_CB(skb)->flags = (TCPCB_FLAG_ACK | TCPCB_FLAG_RST);
TCP_SKB_CB(skb)->sacked = 0;
+ skb_shinfo(skb)->tso_segs = 1;
+ skb_shinfo(skb)->tso_size = 0;
/* Send it off. */
TCP_SKB_CB(skb)->seq = tcp_acceptable_seq(sk, tp);
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq;
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- if (tcp_transmit_skb(sk, skb))
- NET_INC_STATS(TCPAbortFailed);
+ if (tcp_transmit_skb(sk, skb, 0, priority))
+ NET_INC_STATS(LINUX_MIB_TCPABORTFAILED);
}
/* WARNING: This routine must only be called when we have already sent
if (nskb == NULL)
return -ENOMEM;
__skb_unlink(skb, &sk->sk_write_queue);
+ skb_header_release(nskb);
__skb_queue_head(&sk->sk_write_queue, nskb);
- tcp_free_skb(sk, skb);
+ sk_stream_free_skb(sk, skb);
sk_charge_skb(sk, nskb);
skb = nskb;
}
TCP_ECN_send_synack(tcp_sk(sk), skb);
}
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- return tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC));
+ return tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
}
/*
* 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 tcp_opt *tp = tcp_sk(sk);
+ struct inet_request_sock *ireq = inet_rsk(req);
+ struct tcp_sock *tp = tcp_sk(sk);
struct tcphdr *th;
int tcp_header_size;
struct sk_buff *skb;
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);
skb->csum = 0;
th->doff = (tcp_header_size >> 2);
- TCP_INC_STATS(TcpOutSegs);
+ TCP_INC_STATS(TCP_MIB_OUTSEGS);
return skb;
}
/*
* Do all connect socket setups that can be done AF independent.
*/
-static inline void tcp_connect_init(struct sock *sk)
+static void tcp_connect_init(struct sock *sk)
{
struct dst_entry *dst = __sk_dst_get(sk);
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
+ __u8 rcv_wscale;
/* We'll fix this up when we get a response from the other end.
* See tcp_input.c:tcp_rcv_state_process case TCP_SYN_SENT.
(sysctl_tcp_timestamps ? TCPOLEN_TSTAMP_ALIGNED : 0);
/* If user gave his TCP_MAXSEG, record it to clamp */
- if (tp->user_mss)
- tp->mss_clamp = tp->user_mss;
+ if (tp->rx_opt.user_mss)
+ tp->rx_opt.mss_clamp = tp->rx_opt.user_mss;
tp->max_window = 0;
- tcp_sync_mss(sk, dst_pmtu(dst));
+ tcp_sync_mss(sk, dst_mtu(dst));
if (!tp->window_clamp)
tp->window_clamp = dst_metric(dst, RTAX_WINDOW);
tp->advmss = dst_metric(dst, RTAX_ADVMSS);
tcp_initialize_rcv_mss(sk);
- tcp_vegas_init(tp);
tcp_select_initial_window(tcp_full_space(sk),
- tp->advmss - (tp->ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0),
+ tp->advmss - (tp->rx_opt.ts_recent_stamp ? tp->tcp_header_len - sizeof(struct tcphdr) : 0),
&tp->rcv_wnd,
&tp->window_clamp,
sysctl_tcp_window_scaling,
- &tp->rcv_wscale);
+ &rcv_wscale);
+ tp->rx_opt.rcv_wscale = rcv_wscale;
tp->rcv_ssthresh = tp->rcv_wnd;
sk->sk_err = 0;
tp->rcv_wup = 0;
tp->copied_seq = 0;
- tp->rto = TCP_TIMEOUT_INIT;
- tp->retransmits = 0;
+ inet_csk(sk)->icsk_rto = TCP_TIMEOUT_INIT;
+ inet_csk(sk)->icsk_retransmits = 0;
tcp_clear_retrans(tp);
}
*/
int tcp_connect(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *buff;
tcp_connect_init(sk);
- buff = alloc_skb(MAX_TCP_HEADER + 15, sk->sk_allocation);
+ buff = alloc_skb_fclone(MAX_TCP_HEADER + 15, sk->sk_allocation);
if (unlikely(buff == NULL))
return -ENOBUFS;
TCP_SKB_CB(buff)->flags = TCPCB_FLAG_SYN;
TCP_ECN_send_syn(sk, tp, buff);
TCP_SKB_CB(buff)->sacked = 0;
+ skb_shinfo(buff)->tso_segs = 1;
+ skb_shinfo(buff)->tso_size = 0;
buff->csum = 0;
TCP_SKB_CB(buff)->seq = tp->write_seq++;
TCP_SKB_CB(buff)->end_seq = tp->write_seq;
tp->snd_nxt = tp->write_seq;
tp->pushed_seq = tp->write_seq;
- tcp_vegas_init(tp);
/* Send it off. */
TCP_SKB_CB(buff)->when = tcp_time_stamp;
tp->retrans_stamp = TCP_SKB_CB(buff)->when;
+ skb_header_release(buff);
__skb_queue_tail(&sk->sk_write_queue, buff);
sk_charge_skb(sk, buff);
- tp->packets_out++;
- tcp_transmit_skb(sk, skb_clone(buff, GFP_KERNEL));
- TCP_INC_STATS(TcpActiveOpens);
+ tp->packets_out += tcp_skb_pcount(buff);
+ tcp_transmit_skb(sk, buff, 1, GFP_KERNEL);
+ TCP_INC_STATS(TCP_MIB_ACTIVEOPENS);
/* Timer for repeating the SYN until an answer. */
- tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ inet_csk(sk)->icsk_rto, TCP_RTO_MAX);
return 0;
}
*/
void tcp_send_delayed_ack(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
- int ato = tp->ack.ato;
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ int ato = icsk->icsk_ack.ato;
unsigned long timeout;
if (ato > TCP_DELACK_MIN) {
+ const struct tcp_sock *tp = tcp_sk(sk);
int max_ato = HZ/2;
- if (tp->ack.pingpong || (tp->ack.pending&TCP_ACK_PUSHED))
+ if (icsk->icsk_ack.pingpong || (icsk->icsk_ack.pending & ICSK_ACK_PUSHED))
max_ato = TCP_DELACK_MAX;
/* Slow path, intersegment interval is "high". */
/* If some rtt estimate is known, use it to bound delayed ack.
- * Do not use tp->rto here, use results of rtt measurements
+ * Do not use inet_csk(sk)->icsk_rto here, use results of rtt measurements
* directly.
*/
if (tp->srtt) {
timeout = jiffies + ato;
/* Use new timeout only if there wasn't a older one earlier. */
- if (tp->ack.pending&TCP_ACK_TIMER) {
+ if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) {
/* If delack timer was blocked or is about to expire,
* send ACK now.
*/
- if (tp->ack.blocked || time_before_eq(tp->ack.timeout, jiffies+(ato>>2))) {
+ if (icsk->icsk_ack.blocked ||
+ time_before_eq(icsk->icsk_ack.timeout, jiffies + (ato >> 2))) {
tcp_send_ack(sk);
return;
}
- if (!time_before(timeout, tp->ack.timeout))
- timeout = tp->ack.timeout;
+ if (!time_before(timeout, icsk->icsk_ack.timeout))
+ timeout = icsk->icsk_ack.timeout;
}
- tp->ack.pending |= TCP_ACK_SCHED|TCP_ACK_TIMER;
- tp->ack.timeout = timeout;
- sk_reset_timer(sk, &tp->delack_timer, timeout);
+ icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER;
+ icsk->icsk_ack.timeout = timeout;
+ sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout);
}
/* This routine sends an ack and also updates the window. */
{
/* If we have been reset, we may not send again. */
if (sk->sk_state != TCP_CLOSE) {
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *buff;
/* We are not putting this on the write queue, so
*/
buff = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC);
if (buff == NULL) {
- tcp_schedule_ack(tp);
- tp->ack.ato = TCP_ATO_MIN;
- tcp_reset_xmit_timer(sk, TCP_TIME_DACK, TCP_DELACK_MAX);
+ inet_csk_schedule_ack(sk);
+ inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN;
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
+ TCP_DELACK_MAX, TCP_RTO_MAX);
return;
}
buff->csum = 0;
TCP_SKB_CB(buff)->flags = TCPCB_FLAG_ACK;
TCP_SKB_CB(buff)->sacked = 0;
+ skb_shinfo(buff)->tso_segs = 1;
+ skb_shinfo(buff)->tso_size = 0;
/* Send it off, this clears delayed acks for us. */
TCP_SKB_CB(buff)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk, tp);
TCP_SKB_CB(buff)->when = tcp_time_stamp;
- tcp_transmit_skb(sk, buff);
+ tcp_transmit_skb(sk, buff, 0, GFP_ATOMIC);
}
}
*/
static int tcp_xmit_probe_skb(struct sock *sk, int urgent)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
/* We don't queue it, tcp_transmit_skb() sets ownership. */
skb->csum = 0;
TCP_SKB_CB(skb)->flags = TCPCB_FLAG_ACK;
TCP_SKB_CB(skb)->sacked = urgent;
+ skb_shinfo(skb)->tso_segs = 1;
+ skb_shinfo(skb)->tso_size = 0;
/* Use a previous sequence. This should cause the other
* end to send an ack. Don't queue or clone SKB, just
TCP_SKB_CB(skb)->seq = urgent ? tp->snd_una : tp->snd_una - 1;
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq;
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- return tcp_transmit_skb(sk, skb);
+ return tcp_transmit_skb(sk, skb, 0, GFP_ATOMIC);
}
int tcp_write_wakeup(struct sock *sk)
{
if (sk->sk_state != TCP_CLOSE) {
- struct tcp_opt *tp = tcp_sk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
- if ((skb = tp->send_head) != NULL &&
+ if ((skb = sk->sk_send_head) != NULL &&
before(TCP_SKB_CB(skb)->seq, tp->snd_una+tp->snd_wnd)) {
int err;
- int mss = tcp_current_mss(sk, 0);
- int seg_size = tp->snd_una+tp->snd_wnd-TCP_SKB_CB(skb)->seq;
+ unsigned int mss = tcp_current_mss(sk, 0);
+ unsigned int seg_size = tp->snd_una+tp->snd_wnd-TCP_SKB_CB(skb)->seq;
if (before(tp->pushed_seq, TCP_SKB_CB(skb)->end_seq))
tp->pushed_seq = TCP_SKB_CB(skb)->end_seq;
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) {
- sk->sk_no_largesend = 1;
- 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, mss);
+
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- err = tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC));
+ err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
if (!err) {
update_send_head(sk, tp, skb);
}
*/
void tcp_send_probe0(struct sock *sk)
{
- struct tcp_opt *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ struct tcp_sock *tp = tcp_sk(sk);
int err;
err = tcp_write_wakeup(sk);
- if (tp->packets_out || !tp->send_head) {
+ if (tp->packets_out || !sk->sk_send_head) {
/* Cancel probe timer, if it is not required. */
- tp->probes_out = 0;
- tp->backoff = 0;
+ icsk->icsk_probes_out = 0;
+ icsk->icsk_backoff = 0;
return;
}
if (err <= 0) {
- if (tp->backoff < sysctl_tcp_retries2)
- tp->backoff++;
- tp->probes_out++;
- tcp_reset_xmit_timer (sk, TCP_TIME_PROBE0,
- min(tp->rto << tp->backoff, TCP_RTO_MAX));
+ if (icsk->icsk_backoff < sysctl_tcp_retries2)
+ icsk->icsk_backoff++;
+ icsk->icsk_probes_out++;
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
+ min(icsk->icsk_rto << icsk->icsk_backoff, TCP_RTO_MAX),
+ TCP_RTO_MAX);
} else {
/* If packet was not sent due to local congestion,
- * do not backoff and do not remember probes_out.
+ * do not backoff and do not remember icsk_probes_out.
* Let local senders to fight for local resources.
*
* Use accumulated backoff yet.
*/
- if (!tp->probes_out)
- tp->probes_out=1;
- tcp_reset_xmit_timer (sk, TCP_TIME_PROBE0,
- min(tp->rto << tp->backoff, TCP_RESOURCE_PROBE_INTERVAL));
+ if (!icsk->icsk_probes_out)
+ icsk->icsk_probes_out = 1;
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
+ min(icsk->icsk_rto << icsk->icsk_backoff,
+ TCP_RESOURCE_PROBE_INTERVAL),
+ TCP_RTO_MAX);
}
}
-EXPORT_SYMBOL(tcp_acceptable_seq);
EXPORT_SYMBOL(tcp_connect);
-EXPORT_SYMBOL(tcp_connect_init);
EXPORT_SYMBOL(tcp_make_synack);
-EXPORT_SYMBOL(tcp_send_synack);
EXPORT_SYMBOL(tcp_simple_retransmit);
EXPORT_SYMBOL(tcp_sync_mss);
-EXPORT_SYMBOL(tcp_transmit_skb);
-EXPORT_SYMBOL(tcp_write_wakeup);
-EXPORT_SYMBOL(tcp_write_xmit);
+EXPORT_SYMBOL(sysctl_tcp_tso_win_divisor);