#include <linux/compiler.h>
#include <linux/module.h>
-#include <linux/smp_lock.h>
/* People can turn this off for buggy TCP's found in printers etc. */
-int sysctl_tcp_retrans_collapse = 1;
+int sysctl_tcp_retrans_collapse __read_mostly = 1;
+
+/* People can turn this on to work with those rare, broken TCPs that
+ * interpret the window field as a signed quantity.
+ */
+int sysctl_tcp_workaround_signed_windows __read_mostly = 0;
/* 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;
+int sysctl_tcp_tso_win_divisor __read_mostly = 3;
+
+int sysctl_tcp_mtu_probing __read_mostly = 0;
+int sysctl_tcp_base_mss __read_mostly = 512;
+
+/* By default, RFC2861 behavior. */
+int sysctl_tcp_slow_start_after_idle __read_mostly = 1;
-static inline void update_send_head(struct sock *sk, struct tcp_sock *tp,
- struct sk_buff *skb)
+static void update_send_head(struct sock *sk, struct sk_buff *skb)
{
- sk->sk_send_head = skb->next;
- if (sk->sk_send_head == (struct sk_buff *)&sk->sk_write_queue)
- sk->sk_send_head = NULL;
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ tcp_advance_send_head(sk, skb);
tp->snd_nxt = TCP_SKB_CB(skb)->end_seq;
- tcp_packets_out_inc(sk, tp, skb);
+ tcp_packets_out_inc(sk, 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_sock *tp)
+static inline __u32 tcp_acceptable_seq(struct sock *sk)
{
+ struct tcp_sock *tp = tcp_sk(sk);
+
if (!before(tp->snd_una+tp->snd_wnd, tp->snd_nxt))
return tp->snd_nxt;
else
tp->snd_cwnd_used = 0;
}
-static inline void tcp_event_data_sent(struct tcp_sock *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)
{
struct inet_connection_sock *icsk = inet_csk(sk);
const u32 now = tcp_time_stamp;
- if (!tp->packets_out && (s32)(now - tp->lsndtime) > icsk->icsk_rto)
+ if (sysctl_tcp_slow_start_after_idle &&
+ (!tp->packets_out && (s32)(now - tp->lsndtime) > icsk->icsk_rto))
tcp_cwnd_restart(sk, __sk_dst_get(sk));
tp->lsndtime = now;
icsk->icsk_ack.pingpong = 1;
}
-static __inline__ void tcp_event_ack_sent(struct sock *sk, unsigned int pkts)
+static inline void tcp_event_ack_sent(struct sock *sk, unsigned int pkts)
{
tcp_dec_quickack_mode(sk, pkts);
inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
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.
+ * will break some buggy TCP stacks. If the admin tells us
+ * it is likely we could be speaking with such a buggy stack
+ * we will truncate our initial window offering to 32K-1
+ * unless the remote has sent us a window scaling option,
+ * which we interpret as a sign the remote TCP is not
+ * misinterpreting the window field as a signed quantity.
*/
- (*rcv_wnd) = min(space, MAX_TCP_WINDOW);
+ if (sysctl_tcp_workaround_signed_windows)
+ (*rcv_wnd) = min(space, MAX_TCP_WINDOW);
+ else
+ (*rcv_wnd) = space;
+
(*rcv_wscale) = 0;
if (wscale_ok) {
/* Set window scaling on max possible window
- * See RFC1323 for an explanation of the limit to 14
+ * See RFC1323 for an explanation of the limit to 14
*/
space = max_t(u32, sysctl_tcp_rmem[2], sysctl_rmem_max);
+ space = min_t(u32, space, *window_clamp);
while (space > 65535 && (*rcv_wscale) < 14) {
space >>= 1;
(*rcv_wscale)++;
* 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_sock *tp = tcp_sk(sk);
u32 cur_win = tcp_receive_window(tp);
u32 new_win = __tcp_select_window(sk);
/* Never shrink the offered window */
- if(new_win < cur_win) {
+ if (new_win < cur_win) {
/* Danger Will Robinson!
* Don't update rcv_wup/rcv_wnd here or else
* we will not be able to advertise a zero
/* Make sure we do not exceed the maximum possible
* scaled window.
*/
- if (!tp->rx_opt.rcv_wscale)
+ if (!tp->rx_opt.rcv_wscale && sysctl_tcp_workaround_signed_windows)
new_win = min(new_win, MAX_TCP_WINDOW);
else
new_win = min(new_win, (65535U << tp->rx_opt.rcv_wscale));
return new_win;
}
+static void tcp_build_and_update_options(__be32 *ptr, struct tcp_sock *tp,
+ __u32 tstamp, __u8 **md5_hash)
+{
+ if (tp->rx_opt.tstamp_ok) {
+ *ptr++ = 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--;
+ }
+ }
+#ifdef CONFIG_TCP_MD5SIG
+ if (md5_hash) {
+ *ptr++ = htonl((TCPOPT_NOP << 24) |
+ (TCPOPT_NOP << 16) |
+ (TCPOPT_MD5SIG << 8) |
+ TCPOLEN_MD5SIG);
+ *md5_hash = (__u8 *)ptr;
+ }
+#endif
+}
+
+/* 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.
+ *
+ * Note - that with the RFC2385 TCP option, we make room for the
+ * 16 byte MD5 hash. This will be filled in later, so the pointer for the
+ * location to be filled is passed back up.
+ */
+static void tcp_syn_build_options(__be32 *ptr, int mss, int ts, int sack,
+ int offer_wscale, int wscale, __u32 tstamp,
+ __u32 ts_recent, __u8 **md5_hash)
+{
+ /* 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++ = htonl((TCPOPT_SACK_PERM << 24) |
+ (TCPOLEN_SACK_PERM << 16) |
+ (TCPOPT_TIMESTAMP << 8) |
+ TCPOLEN_TIMESTAMP);
+ else
+ *ptr++ = 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++ = 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));
+#ifdef CONFIG_TCP_MD5SIG
+ /*
+ * If MD5 is enabled, then we set the option, and include the size
+ * (always 18). The actual MD5 hash is added just before the
+ * packet is sent.
+ */
+ if (md5_hash) {
+ *ptr++ = htonl((TCPOPT_NOP << 24) |
+ (TCPOPT_NOP << 16) |
+ (TCPOPT_MD5SIG << 8) |
+ TCPOLEN_MD5SIG);
+ *md5_hash = (__u8 *) ptr;
+ }
+#endif
+}
/* This routine actually transmits TCP packets queued in by
* tcp_do_sendmsg(). This is used by both the initial
struct tcp_sock *tp;
struct tcp_skb_cb *tcb;
int tcp_header_size;
+#ifdef CONFIG_TCP_MD5SIG
+ struct tcp_md5sig_key *md5;
+ __u8 *md5_hash_location;
+#endif
struct tcphdr *th;
int sysctl_flags;
int err;
/* If congestion control is doing timestamping, we must
* take such a timestamp before we potentially clone/copy.
*/
- if (icsk->icsk_ca_ops->rtt_sample)
+ if (icsk->icsk_ca_ops->flags & TCP_CONG_RTT_STAMP)
__net_timestamp(skb);
if (likely(clone_it)) {
sysctl_flags = 0;
if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) {
tcp_header_size = sizeof(struct tcphdr) + TCPOLEN_MSS;
- if(sysctl_tcp_timestamps) {
+ if (sysctl_tcp_timestamps) {
tcp_header_size += TCPOLEN_TSTAMP_ALIGNED;
sysctl_flags |= SYSCTL_FLAG_TSTAMPS;
}
(tp->rx_opt.eff_sacks *
TCPOLEN_SACK_PERBLOCK));
}
-
+
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;
+#ifdef CONFIG_TCP_MD5SIG
+ /*
+ * Are we doing MD5 on this segment? If so - make
+ * room for it.
+ */
+ md5 = tp->af_specific->md5_lookup(sk, sk);
+ if (md5)
+ tcp_header_size += TCPOLEN_MD5SIG_ALIGNED;
+#endif
+
+ skb_push(skb, tcp_header_size);
+ skb_reset_transport_header(skb);
skb_set_owner_w(skb, sk);
/* Build TCP header and checksum it. */
+ th = tcp_hdr(skb);
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) |
+ *(((__be16 *)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.
*/
- th->window = htons(tp->rcv_wnd);
+ th->window = htons(min(tp->rcv_wnd, 65535U));
} else {
th->window = htons(tcp_select_window(sk));
}
}
if (unlikely(tcb->flags & TCPCB_FLAG_SYN)) {
- tcp_syn_build_options((__u32 *)(th + 1),
+ tcp_syn_build_options((__be32 *)(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);
+ tp->rx_opt.ts_recent,
+
+#ifdef CONFIG_TCP_MD5SIG
+ md5 ? &md5_hash_location :
+#endif
+ NULL);
} else {
- tcp_build_and_update_options((__u32 *)(th + 1),
- tp, tcb->when);
- TCP_ECN_send(sk, tp, skb, tcp_header_size);
+ tcp_build_and_update_options((__be32 *)(th + 1),
+ tp, tcb->when,
+#ifdef CONFIG_TCP_MD5SIG
+ md5 ? &md5_hash_location :
+#endif
+ NULL);
+ TCP_ECN_send(sk, skb, tcp_header_size);
+ }
+
+#ifdef CONFIG_TCP_MD5SIG
+ /* Calculate the MD5 hash, as we have all we need now */
+ if (md5) {
+ tp->af_specific->calc_md5_hash(md5_hash_location,
+ md5,
+ sk, NULL, NULL,
+ tcp_hdr(skb),
+ sk->sk_protocol,
+ skb->len);
}
+#endif
icsk->icsk_af_ops->send_check(sk, skb->len, skb);
if (skb->len != tcp_header_size)
tcp_event_data_sent(tp, skb, sk);
- TCP_INC_STATS(TCP_MIB_OUTSEGS);
+ if (after(tcb->end_seq, tp->snd_nxt) || tcb->seq == tcb->end_seq)
+ TCP_INC_STATS(TCP_MIB_OUTSEGS);
err = icsk->icsk_af_ops->queue_xmit(skb, 0);
- if (unlikely(err <= 0))
+ if (likely(err <= 0))
return err;
- tcp_enter_cwr(sk);
+ tcp_enter_cwr(sk, 1);
- /* 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 net_xmit_eval(err);
#undef SYSCTL_FLAG_TSTAMPS
#undef SYSCTL_FLAG_WSCALE
}
-/* This routine just queue's the buffer
+/* This routine just queue's the buffer
*
* NOTE: probe0 timer is not checked, do not forget tcp_push_pending_frames,
* otherwise socket can stall.
/* 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);
+ tcp_add_write_queue_tail(sk, skb);
sk_charge_skb(sk, skb);
-
- /* Queue it, remembering where we must start sending. */
- if (sk->sk_send_head == NULL)
- sk->sk_send_head = skb;
}
static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned int mss_now)
{
- if (skb->len <= mss_now ||
- !(sk->sk_route_caps & NETIF_F_TSO)) {
+ if (skb->len <= mss_now || !sk_can_gso(sk)) {
/* Avoid the costly divide in the normal
* non-TSO case.
*/
- skb_shinfo(skb)->tso_segs = 1;
- skb_shinfo(skb)->tso_size = 0;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
} else {
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;
+ skb_shinfo(skb)->gso_segs = factor;
+ skb_shinfo(skb)->gso_size = mss_now;
+ skb_shinfo(skb)->gso_type = sk->sk_gso_type;
}
}
/* Function to create two new TCP segments. Shrinks the given segment
* to the specified size and appends a new segment with the rest of the
- * packet to the list. This won't be called frequently, I hope.
+ * packet to the list. This won't be called frequently, I hope.
* Remember, these are still headerless SKBs at this point.
*/
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;
int nsize, old_factor;
+ int nlen;
u16 flags;
BUG_ON(len > skb->len);
- clear_all_retrans_hints(tp);
+ clear_all_retrans_hints(tp);
nsize = skb_headlen(skb) - len;
if (nsize < 0)
nsize = 0;
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);
+ nlen = skb->len - len - nsize;
+ 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)->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) {
+ if (!skb_shinfo(skb)->nr_frags && skb->ip_summed != CHECKSUM_PARTIAL) {
/* Copy and checksum data tail into the new buffer. */
buff->csum = csum_partial_copy_nocheck(skb->data + len, skb_put(buff, nsize),
nsize, 0);
skb->csum = csum_block_sub(skb->csum, buff->csum, len);
} else {
- skb->ip_summed = CHECKSUM_HW;
+ skb->ip_summed = CHECKSUM_PARTIAL;
skb_split(skb, buff, len);
}
tp->fackets_out -= diff;
if ((int)tp->fackets_out < 0)
tp->fackets_out = 0;
+ /* SACK fastpath might overwrite it unless dealt with */
+ if (tp->fastpath_skb_hint != NULL &&
+ after(TCP_SKB_CB(tp->fastpath_skb_hint)->seq,
+ TCP_SKB_CB(skb)->seq)) {
+ tp->fastpath_cnt_hint -= diff;
+ if ((int)tp->fastpath_cnt_hint < 0)
+ tp->fastpath_cnt_hint = 0;
+ }
}
}
/* Link BUFF into the send queue. */
skb_header_release(buff);
- __skb_append(skb, buff, &sk->sk_write_queue);
+ tcp_insert_write_queue_after(skb, buff, sk);
return 0;
}
* eventually). The difference is that pulled data not copied, but
* immediately discarded.
*/
-static unsigned char *__pskb_trim_head(struct sk_buff *skb, int len)
+static void __pskb_trim_head(struct sk_buff *skb, int len)
{
int i, k, eat;
}
skb_shinfo(skb)->nr_frags = k;
- skb->tail = skb->data;
+ skb_reset_tail_pointer(skb);
skb->data_len -= len;
skb->len = skb->data_len;
- return skb->tail;
}
int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len)
pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
return -ENOMEM;
- if (len <= skb_headlen(skb)) {
+ /* If len == headlen, we avoid __skb_pull to preserve alignment. */
+ if (unlikely(len < skb_headlen(skb)))
__skb_pull(skb, len);
- } else {
- if (__pskb_trim_head(skb, len-skb_headlen(skb)) == NULL)
- return -ENOMEM;
- }
+ else
+ __pskb_trim_head(skb, len - skb_headlen(skb));
TCP_SKB_CB(skb)->seq += len;
- skb->ip_summed = CHECKSUM_HW;
+ skb->ip_summed = CHECKSUM_PARTIAL;
skb->truesize -= len;
sk->sk_wmem_queued -= len;
return 0;
}
+/* Not accounting for SACKs here. */
+int tcp_mtu_to_mss(struct sock *sk, int pmtu)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ int mss_now;
+
+ /* Calculate base mss without TCP options:
+ It is MMS_S - sizeof(tcphdr) of rfc1122
+ */
+ 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->rx_opt.mss_clamp)
+ mss_now = tp->rx_opt.mss_clamp;
+
+ /* Now subtract optional transport overhead */
+ 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 = 48;
+
+ /* Now subtract TCP options size, not including SACKs */
+ mss_now -= tp->tcp_header_len - sizeof(struct tcphdr);
+
+ return mss_now;
+}
+
+/* Inverse of above */
+int tcp_mss_to_mtu(struct sock *sk, int mss)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ int mtu;
+
+ mtu = mss +
+ tp->tcp_header_len +
+ icsk->icsk_ext_hdr_len +
+ icsk->icsk_af_ops->net_header_len;
+
+ return mtu;
+}
+
+void tcp_mtup_init(struct sock *sk)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
+
+ icsk->icsk_mtup.enabled = sysctl_tcp_mtu_probing > 1;
+ icsk->icsk_mtup.search_high = tp->rx_opt.mss_clamp + sizeof(struct tcphdr) +
+ icsk->icsk_af_ops->net_header_len;
+ icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, sysctl_tcp_base_mss);
+ icsk->icsk_mtup.probe_size = 0;
+}
+
/* This function synchronize snd mss to current pmtu/exthdr set.
tp->rx_opt.user_mss is mss set by user by TCP_MAXSEG. It does NOT counts
{
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
- */
- 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->rx_opt.mss_clamp)
- mss_now = tp->rx_opt.mss_clamp;
+ int mss_now;
- /* Now subtract optional transport overhead */
- mss_now -= icsk->icsk_ext_hdr_len;
+ if (icsk->icsk_mtup.search_high > pmtu)
+ icsk->icsk_mtup.search_high = pmtu;
- /* Then reserve room for full set of TCP options and 8 bytes of data */
- if (mss_now < 48)
- mss_now = 48;
-
- /* Now subtract TCP options size, not including SACKs */
- mss_now -= tp->tcp_header_len - sizeof(struct tcphdr);
+ mss_now = tcp_mtu_to_mss(sk, pmtu);
/* Bound mss with half of window */
if (tp->max_window && mss_now > (tp->max_window>>1))
/* And store cached results */
icsk->icsk_pmtu_cookie = pmtu;
+ if (icsk->icsk_mtup.enabled)
+ mss_now = min(mss_now, tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low));
tp->mss_cache = mss_now;
return mss_now;
mss_now = tp->mss_cache;
- if (large_allowed &&
- (sk->sk_route_caps & NETIF_F_TSO) &&
- !tp->urg_mode)
+ if (large_allowed && sk_can_gso(sk) && !tp->urg_mode)
doing_tso = 1;
if (dst) {
mss_now -= (TCPOLEN_SACK_BASE_ALIGNED +
(tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK));
+#ifdef CONFIG_TCP_MD5SIG
+ if (tp->af_specific->md5_lookup(sk, sk))
+ mss_now -= TCPOLEN_MD5SIG_ALIGNED;
+#endif
+
xmit_size_goal = mss_now;
if (doing_tso) {
/* Congestion window validation. (RFC2861) */
-static inline void tcp_cwnd_validate(struct sock *sk, struct tcp_sock *tp)
+static void tcp_cwnd_validate(struct sock *sk)
{
+ struct tcp_sock *tp = tcp_sk(sk);
__u32 packets_out = tp->packets_out;
if (packets_out >= tp->snd_cwnd) {
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)
+ if (sysctl_tcp_slow_start_after_idle &&
+ (s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >= inet_csk(sk)->icsk_rto)
tcp_cwnd_application_limited(sk);
}
}
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)
+ if ((TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN) &&
+ tcp_skb_pcount(skb) == 1)
return 1;
in_flight = tcp_packets_in_flight(tp);
/* 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)
+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_skb_mss(skb) != mss_now)) {
tcp_set_skb_tso_segs(sk, skb, mss_now);
tso_segs = tcp_skb_pcount(skb);
}
*/
static inline int tcp_nagle_check(const struct tcp_sock *tp,
- const struct sk_buff *skb,
+ const struct sk_buff *skb,
unsigned mss_now, int nonagle)
{
return (skb->len < mss_now &&
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 ||
+ /* Don't use the nagle rule for urgent data (or for the final FIN).
+ * Nagle can be ignored during F-RTO too (see RFC4138).
+ */
+ if (tp->urg_mode || (tp->frto_counter == 2) ||
(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN))
return 1;
return !after(end_seq, tp->snd_una + tp->snd_wnd);
}
-/* This checks if the data bearing packet SKB (usually sk->sk_send_head)
+/* This checks if the data bearing packet SKB (usually tcp_send_head(sk))
* should be put on the wire right now. If so, it returns the number of
* packets allowed by the congestion window.
*/
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)
+int tcp_may_send_now(struct sock *sk)
{
- struct sk_buff *skb = sk->sk_send_head;
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct sk_buff *skb = tcp_send_head(sk);
return (skb &&
tcp_snd_test(sk, skb, tcp_current_mss(sk, 1),
if (unlikely(buff == NULL))
return -ENOMEM;
- buff->truesize = nlen;
+ sk_charge_skb(sk, buff);
+ buff->truesize += nlen;
skb->truesize -= nlen;
/* Correct the sequence numbers. */
/* 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;
+ buff->ip_summed = skb->ip_summed = CHECKSUM_PARTIAL;
skb_split(skb, buff, len);
/* Fix up tso_factor for both original and new SKB. */
/* Link BUFF into the send queue. */
skb_header_release(buff);
- __skb_append(skb, buff, &sk->sk_write_queue);
+ tcp_insert_write_queue_after(skb, buff, sk);
return 0;
}
*
* This algorithm is from John Heffner.
*/
-static int tcp_tso_should_defer(struct sock *sk, struct tcp_sock *tp, struct sk_buff *skb)
+static int tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb)
{
+ struct tcp_sock *tp = tcp_sk(sk);
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;
+ goto send_now;
if (icsk->icsk_ca_state != TCP_CA_Open)
- return 0;
+ goto send_now;
+
+ /* Defer for less than two clock ticks. */
+ if (!tp->tso_deferred && ((jiffies<<1)>>1) - (tp->tso_deferred>>1) > 1)
+ goto send_now;
in_flight = tcp_packets_in_flight(tp);
limit = min(send_win, cong_win);
+ /* If a full-sized TSO skb can be sent, do it. */
+ if (limit >= 65536)
+ goto send_now;
+
if (sysctl_tcp_tso_win_divisor) {
u32 chunk = min(tp->snd_wnd, tp->snd_cwnd * tp->mss_cache);
*/
chunk /= sysctl_tcp_tso_win_divisor;
if (limit >= chunk)
- return 0;
+ goto send_now;
} else {
/* Different approach, try not to defer past a single
* ACK. Receiver should ACK every other full sized
* then send now.
*/
if (limit > tcp_max_burst(tp) * tp->mss_cache)
- return 0;
+ goto send_now;
}
/* Ok, it looks like it is advisable to defer. */
+ tp->tso_deferred = 1 | (jiffies<<1);
+
return 1;
+
+send_now:
+ tp->tso_deferred = 0;
+ return 0;
+}
+
+/* Create a new MTU probe if we are ready.
+ * Returns 0 if we should wait to probe (no cwnd available),
+ * 1 if a probe was sent,
+ * -1 otherwise */
+static int tcp_mtu_probe(struct sock *sk)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ struct sk_buff *skb, *nskb, *next;
+ int len;
+ int probe_size;
+ unsigned int pif;
+ int copy;
+ int mss_now;
+
+ /* Not currently probing/verifying,
+ * not in recovery,
+ * have enough cwnd, and
+ * not SACKing (the variable headers throw things off) */
+ if (!icsk->icsk_mtup.enabled ||
+ icsk->icsk_mtup.probe_size ||
+ inet_csk(sk)->icsk_ca_state != TCP_CA_Open ||
+ tp->snd_cwnd < 11 ||
+ tp->rx_opt.eff_sacks)
+ return -1;
+
+ /* Very simple search strategy: just double the MSS. */
+ mss_now = tcp_current_mss(sk, 0);
+ probe_size = 2*tp->mss_cache;
+ if (probe_size > tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_high)) {
+ /* TODO: set timer for probe_converge_event */
+ return -1;
+ }
+
+ /* Have enough data in the send queue to probe? */
+ len = 0;
+ if ((skb = tcp_send_head(sk)) == NULL)
+ return -1;
+ while ((len += skb->len) < probe_size && !tcp_skb_is_last(sk, skb))
+ skb = tcp_write_queue_next(sk, skb);
+ if (len < probe_size)
+ return -1;
+
+ /* Receive window check. */
+ if (after(TCP_SKB_CB(skb)->seq + probe_size, tp->snd_una + tp->snd_wnd)) {
+ if (tp->snd_wnd < probe_size)
+ return -1;
+ else
+ return 0;
+ }
+
+ /* Do we need to wait to drain cwnd? */
+ pif = tcp_packets_in_flight(tp);
+ if (pif + 2 > tp->snd_cwnd) {
+ /* With no packets in flight, don't stall. */
+ if (pif == 0)
+ return -1;
+ else
+ return 0;
+ }
+
+ /* We're allowed to probe. Build it now. */
+ if ((nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC)) == NULL)
+ return -1;
+ sk_charge_skb(sk, nskb);
+
+ skb = tcp_send_head(sk);
+ tcp_insert_write_queue_before(nskb, skb, sk);
+ tcp_advance_send_head(sk, skb);
+
+ TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(skb)->seq;
+ TCP_SKB_CB(nskb)->end_seq = TCP_SKB_CB(skb)->seq + probe_size;
+ TCP_SKB_CB(nskb)->flags = TCPCB_FLAG_ACK;
+ TCP_SKB_CB(nskb)->sacked = 0;
+ nskb->csum = 0;
+ nskb->ip_summed = skb->ip_summed;
+
+ len = 0;
+ while (len < probe_size) {
+ next = tcp_write_queue_next(sk, skb);
+
+ copy = min_t(int, skb->len, probe_size - len);
+ if (nskb->ip_summed)
+ skb_copy_bits(skb, 0, skb_put(nskb, copy), copy);
+ else
+ nskb->csum = skb_copy_and_csum_bits(skb, 0,
+ skb_put(nskb, copy), copy, nskb->csum);
+
+ if (skb->len <= copy) {
+ /* We've eaten all the data from this skb.
+ * Throw it away. */
+ TCP_SKB_CB(nskb)->flags |= TCP_SKB_CB(skb)->flags;
+ tcp_unlink_write_queue(skb, sk);
+ sk_stream_free_skb(sk, skb);
+ } else {
+ TCP_SKB_CB(nskb)->flags |= TCP_SKB_CB(skb)->flags &
+ ~(TCPCB_FLAG_FIN|TCPCB_FLAG_PSH);
+ if (!skb_shinfo(skb)->nr_frags) {
+ skb_pull(skb, copy);
+ if (skb->ip_summed != CHECKSUM_PARTIAL)
+ skb->csum = csum_partial(skb->data, skb->len, 0);
+ } else {
+ __pskb_trim_head(skb, copy);
+ tcp_set_skb_tso_segs(sk, skb, mss_now);
+ }
+ TCP_SKB_CB(skb)->seq += copy;
+ }
+
+ len += copy;
+ skb = next;
+ }
+ tcp_init_tso_segs(sk, nskb, nskb->len);
+
+ /* We're ready to send. If this fails, the probe will
+ * be resegmented into mss-sized pieces by tcp_write_xmit(). */
+ TCP_SKB_CB(nskb)->when = tcp_time_stamp;
+ if (!tcp_transmit_skb(sk, nskb, 1, GFP_ATOMIC)) {
+ /* Decrement cwnd here because we are sending
+ * effectively two packets. */
+ tp->snd_cwnd--;
+ update_send_head(sk, nskb);
+
+ icsk->icsk_mtup.probe_size = tcp_mss_to_mtu(sk, nskb->len);
+ tp->mtu_probe.probe_seq_start = TCP_SKB_CB(nskb)->seq;
+ tp->mtu_probe.probe_seq_end = TCP_SKB_CB(nskb)->end_seq;
+
+ return 1;
+ }
+
+ return -1;
}
+
/* This routine writes packets to the network. It advances the
* send_head. This happens as incoming acks open up the remote
* window for us.
struct sk_buff *skb;
unsigned int tso_segs, sent_pkts;
int cwnd_quota;
+ int result;
/* If we are closed, the bytes will have to remain here.
* In time closedown will finish, we empty the write queue and all
return 0;
sent_pkts = 0;
- while ((skb = sk->sk_send_head)) {
+
+ /* Do MTU probing. */
+ if ((result = tcp_mtu_probe(sk)) == 0) {
+ return 0;
+ } else if (result > 0) {
+ sent_pkts = 1;
+ }
+
+ while ((skb = tcp_send_head(sk))) {
unsigned int limit;
tso_segs = tcp_init_tso_segs(sk, skb, mss_now);
nonagle : TCP_NAGLE_PUSH))))
break;
} else {
- if (tcp_tso_should_defer(sk, tp, skb))
+ if (tcp_tso_should_defer(sk, skb))
break;
}
/* Advance the send_head. This one is sent out.
* This call will increment packets_out.
*/
- update_send_head(sk, tp, skb);
+ update_send_head(sk, skb);
tcp_minshall_update(tp, mss_now, skb);
sent_pkts++;
}
if (likely(sent_pkts)) {
- tcp_cwnd_validate(sk, tp);
+ tcp_cwnd_validate(sk);
return 0;
}
- return !tp->packets_out && sk->sk_send_head;
+ return !tp->packets_out && tcp_send_head(sk);
}
/* 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)
+void __tcp_push_pending_frames(struct sock *sk, unsigned int cur_mss,
+ int nonagle)
{
- struct sk_buff *skb = sk->sk_send_head;
+ struct sk_buff *skb = tcp_send_head(sk);
if (skb) {
if (tcp_write_xmit(sk, cur_mss, nonagle))
- tcp_check_probe_timer(sk, tp);
+ tcp_check_probe_timer(sk);
}
}
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;
+ struct sk_buff *skb = tcp_send_head(sk);
unsigned int tso_segs, cwnd_quota;
BUG_ON(!skb || skb->len < mss_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);
+ update_send_head(sk, skb);
+ tcp_cwnd_validate(sk);
return;
}
}
/* This function returns the amount that we can raise the
* usable window based on the following constraints
- *
+ *
* 1. The window can never be shrunk once it is offered (RFC 793)
* 2. We limit memory per socket
*
* side SWS prevention criteria. The problem is that under this rule
* a stream of single byte packets will cause the right side of the
* window to always advance by a single byte.
- *
+ *
* Of course, if the sender implements sender side SWS prevention
* then this will not be a problem.
- *
+ *
* BSD seems to make the following compromise:
- *
+ *
* If the free space is less than the 1/4 of the maximum
* space available and the free space is less than 1/2 mss,
* then set the window to 0.
int window;
if (mss > full_space)
- mss = full_space;
+ mss = full_space;
if (free_space < full_space/2) {
icsk->icsk_ack.quick = 0;
*/
if (window <= free_space - mss || window > free_space)
window = (free_space/mss)*mss;
+ else if (mss == full_space &&
+ free_space > window + full_space/2)
+ window = free_space;
}
return window;
static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int mss_now)
{
struct tcp_sock *tp = tcp_sk(sk);
- struct sk_buff *next_skb = skb->next;
+ struct sk_buff *next_skb = tcp_write_queue_next(sk, skb);
/* The first test we must make is that neither of these two
* SKB's are still referenced by someone else.
u16 flags = TCP_SKB_CB(skb)->flags;
/* Also punt if next skb has been SACK'd. */
- if(TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_ACKED)
+ if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_ACKED)
return;
/* Next skb is out of window. */
clear_all_retrans_hints(tp);
/* Ok. We will be able to collapse the packet. */
- __skb_unlink(next_skb, &sk->sk_write_queue);
+ tcp_unlink_write_queue(next_skb, sk);
- memcpy(skb_put(skb, next_skb_size), next_skb->data, next_skb_size);
+ skb_copy_from_linear_data(next_skb,
+ skb_put(skb, next_skb_size),
+ next_skb_size);
- if (next_skb->ip_summed == CHECKSUM_HW)
- skb->ip_summed = CHECKSUM_HW;
+ if (next_skb->ip_summed == CHECKSUM_PARTIAL)
+ skb->ip_summed = CHECKSUM_PARTIAL;
- if (skb->ip_summed != CHECKSUM_HW)
+ if (skb->ip_summed != CHECKSUM_PARTIAL)
skb->csum = csum_block_add(skb->csum, next_skb->csum, skb_size);
/* Update sequence range on original skb. */
}
/* Do a simple retransmit without using the backoff mechanisms in
- * tcp_timer. This is used for path mtu discovery.
+ * tcp_timer. This is used for path mtu discovery.
* The socket is already locked here.
- */
+ */
void tcp_simple_retransmit(struct sock *sk)
{
const struct inet_connection_sock *icsk = inet_csk(sk);
unsigned int mss = tcp_current_mss(sk, 0);
int lost = 0;
- sk_stream_for_retrans_queue(skb, sk) {
- if (skb->len > mss &&
+ tcp_for_write_queue(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
+ 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;
tcp_sync_left_out(tp);
- /* Don't muck with the congestion window here.
+ /* Don't muck with the congestion window here.
* Reason is that we do not increase amount of _data_
* in network, but units changed and effective
* cwnd/ssthresh really reduced now.
int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb)
{
struct tcp_sock *tp = tcp_sk(sk);
- unsigned int cur_mss = tcp_current_mss(sk, 0);
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ unsigned int cur_mss = tcp_current_mss(sk, 0);
int err;
+ /* Inconslusive MTU probe */
+ if (icsk->icsk_mtup.probe_size) {
+ icsk->icsk_mtup.probe_size = 0;
+ }
+
/* Do not sent more than we queued. 1/4 is reserved for possible
* copying overhead: fragmentation, tunneling, mangling etc.
*/
}
/* 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 != 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))
+ if (!(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_SYN) &&
+ (skb->len < (cur_mss >> 1)) &&
+ (tcp_write_queue_next(sk, skb) != tcp_send_head(sk)) &&
+ (!tcp_skb_is_last(sk, skb)) &&
+ (skb_shinfo(skb)->nr_frags == 0 && skb_shinfo(tcp_write_queue_next(sk, skb))->nr_frags == 0) &&
+ (tcp_skb_pcount(skb) == 1 && tcp_skb_pcount(tcp_write_queue_next(sk, skb)) == 1) &&
+ (sysctl_tcp_retrans_collapse != 0))
tcp_retrans_try_collapse(sk, skb, cur_mss);
if (inet_csk(sk)->icsk_af_ops->rebuild_header(sk))
* retransmit when old data is attached. So strip it off
* since it is cheap to do so and saves bytes on the network.
*/
- if(skb->len > 0 &&
- (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN) &&
- tp->snd_una == (TCP_SKB_CB(skb)->end_seq - 1)) {
+ if (skb->len > 0 &&
+ (TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN) &&
+ 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_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
skb->ip_summed = CHECKSUM_NONE;
skb->csum = 0;
}
skb = tp->retransmit_skb_hint;
packet_cnt = tp->retransmit_cnt_hint;
}else{
- skb = sk->sk_write_queue.next;
+ skb = tcp_write_queue_head(sk);
packet_cnt = 0;
}
/* First pass: retransmit lost packets. */
if (tp->lost_out) {
- sk_stream_for_retrans_queue_from(skb, sk) {
+ tcp_for_write_queue_from(skb, sk) {
__u8 sacked = TCP_SKB_CB(skb)->sacked;
+ if (skb == tcp_send_head(sk))
+ break;
/* we could do better than to assign each time */
tp->retransmit_skb_hint = skb;
tp->retransmit_cnt_hint = packet_cnt;
else
NET_INC_STATS_BH(LINUX_MIB_TCPSLOWSTARTRETRANS);
- if (skb ==
- skb_peek(&sk->sk_write_queue))
+ if (skb == tcp_write_queue_head(sk))
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
inet_csk(sk)->icsk_rto,
TCP_RTO_MAX);
* segments to send.
*/
- if (tcp_may_send_now(sk, tp))
+ if (tcp_may_send_now(sk))
return;
if (tp->forward_skb_hint) {
skb = tp->forward_skb_hint;
packet_cnt = tp->forward_cnt_hint;
} else{
- skb = sk->sk_write_queue.next;
+ skb = tcp_write_queue_head(sk);
packet_cnt = 0;
}
- sk_stream_for_retrans_queue_from(skb, sk) {
+ tcp_for_write_queue_from(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
tp->forward_cnt_hint = packet_cnt;
tp->forward_skb_hint = skb;
break;
}
- if (skb == skb_peek(&sk->sk_write_queue))
+ if (skb == tcp_write_queue_head(sk))
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
inet_csk(sk)->icsk_rto,
TCP_RTO_MAX);
*/
void tcp_send_fin(struct sock *sk)
{
- struct tcp_sock *tp = tcp_sk(sk);
- struct sk_buff *skb = skb_peek_tail(&sk->sk_write_queue);
+ struct tcp_sock *tp = tcp_sk(sk);
+ struct sk_buff *skb = tcp_write_queue_tail(sk);
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);
- if (sk->sk_send_head != NULL) {
+ if (tcp_send_head(sk) != NULL) {
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_FIN;
TCP_SKB_CB(skb)->end_seq++;
tp->write_seq++;
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;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
/* FIN eats a sequence byte, write_seq advanced by tcp_queue_skb(). */
TCP_SKB_CB(skb)->seq = tp->write_seq;
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(skb)->seq + 1;
tcp_queue_skb(sk, skb);
}
- __tcp_push_pending_frames(sk, tp, mss_now, TCP_NAGLE_OFF);
+ __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_OFF);
}
/* We get here when a process closes a file descriptor (either due to
* an explicit close() or as a byproduct of exit()'ing) and there
* was unread data in the receive queue. This behavior is recommended
- * by draft-ietf-tcpimpl-prob-03.txt section 3.10. -DaveM
+ * by RFC 2525, section 2.17. -DaveM
*/
void tcp_send_active_reset(struct sock *sk, gfp_t priority)
{
- struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
/* NOTE: No TCP options attached and we never retransmit this. */
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;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
/* Send it off. */
- TCP_SKB_CB(skb)->seq = tcp_acceptable_seq(sk, tp);
+ TCP_SKB_CB(skb)->seq = tcp_acceptable_seq(sk);
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, 0, priority))
{
struct sk_buff* skb;
- skb = skb_peek(&sk->sk_write_queue);
+ skb = tcp_write_queue_head(sk);
if (skb == NULL || !(TCP_SKB_CB(skb)->flags&TCPCB_FLAG_SYN)) {
printk(KERN_DEBUG "tcp_send_synack: wrong queue state\n");
return -EFAULT;
struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
if (nskb == NULL)
return -ENOMEM;
- __skb_unlink(skb, &sk->sk_write_queue);
+ tcp_unlink_write_queue(skb, sk);
skb_header_release(nskb);
- __skb_queue_head(&sk->sk_write_queue, nskb);
+ __tcp_add_write_queue_head(sk, nskb);
sk_stream_free_skb(sk, skb);
sk_charge_skb(sk, nskb);
skb = nskb;
struct tcphdr *th;
int tcp_header_size;
struct sk_buff *skb;
+#ifdef CONFIG_TCP_MD5SIG
+ struct tcp_md5sig_key *md5;
+ __u8 *md5_hash_location;
+#endif
skb = sock_wmalloc(sk, MAX_TCP_HEADER + 15, 1, GFP_ATOMIC);
if (skb == NULL)
(ireq->wscale_ok ? TCPOLEN_WSCALE_ALIGNED : 0) +
/* SACK_PERM is in the place of NOP NOP of TS */
((ireq->sack_ok && !ireq->tstamp_ok) ? TCPOLEN_SACKPERM_ALIGNED : 0));
- skb->h.th = th = (struct tcphdr *) skb_push(skb, tcp_header_size);
+#ifdef CONFIG_TCP_MD5SIG
+ /* Are we doing MD5 on this segment? If so - make room for it */
+ md5 = tcp_rsk(req)->af_specific->md5_lookup(sk, req);
+ if (md5)
+ tcp_header_size += TCPOLEN_MD5SIG_ALIGNED;
+#endif
+ skb_push(skb, tcp_header_size);
+ skb_reset_transport_header(skb);
+
+ th = tcp_hdr(skb);
memset(th, 0, sizeof(struct tcphdr));
th->syn = 1;
th->ack = 1;
- if (dst->dev->features&NETIF_F_TSO)
- ireq->ecn_ok = 0;
TCP_ECN_make_synack(req, th);
th->source = inet_sk(sk)->sport;
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;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
th->seq = htonl(TCP_SKB_CB(skb)->seq);
th->ack_seq = htonl(tcp_rsk(req)->rcv_isn + 1);
if (req->rcv_wnd == 0) { /* ignored for retransmitted syns */
- __u8 rcv_wscale;
+ __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),
+ tcp_select_initial_window(tcp_full_space(sk),
dst_metric(dst, RTAX_ADVMSS) - (ireq->tstamp_ok ? TCPOLEN_TSTAMP_ALIGNED : 0),
&req->rcv_wnd,
&req->window_clamp,
ireq->wscale_ok,
&rcv_wscale);
- ireq->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);
+ th->window = htons(min(req->rcv_wnd, 65535U));
TCP_SKB_CB(skb)->when = tcp_time_stamp;
- tcp_syn_build_options((__u32 *)(th + 1), dst_metric(dst, RTAX_ADVMSS), ireq->tstamp_ok,
+ tcp_syn_build_options((__be32 *)(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);
+ req->ts_recent,
+ (
+#ifdef CONFIG_TCP_MD5SIG
+ md5 ? &md5_hash_location :
+#endif
+ NULL)
+ );
skb->csum = 0;
th->doff = (tcp_header_size >> 2);
TCP_INC_STATS(TCP_MIB_OUTSEGS);
+
+#ifdef CONFIG_TCP_MD5SIG
+ /* Okay, we have all we need - do the md5 hash if needed */
+ if (md5) {
+ tp->af_specific->calc_md5_hash(md5_hash_location,
+ md5,
+ NULL, dst, req,
+ tcp_hdr(skb), sk->sk_protocol,
+ skb->len);
+ }
+#endif
+
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_sock *tp = tcp_sk(sk);
tp->tcp_header_len = sizeof(struct tcphdr) +
(sysctl_tcp_timestamps ? TCPOLEN_TSTAMP_ALIGNED : 0);
+#ifdef CONFIG_TCP_MD5SIG
+ if (tp->af_specific->md5_lookup(sk, sk) != NULL)
+ tp->tcp_header_len += TCPOLEN_MD5SIG_ALIGNED;
+#endif
+
/* If user gave his TCP_MAXSEG, record it to clamp */
if (tp->rx_opt.user_mss)
tp->rx_opt.mss_clamp = tp->rx_opt.user_mss;
tp->max_window = 0;
+ tcp_mtup_init(sk);
tcp_sync_mss(sk, dst_mtu(dst));
if (!tp->window_clamp)
/*
* Build a SYN and send it off.
- */
+ */
int tcp_connect(struct sock *sk)
{
struct tcp_sock *tp = tcp_sk(sk);
skb_reserve(buff, MAX_TCP_HEADER);
TCP_SKB_CB(buff)->flags = TCPCB_FLAG_SYN;
- TCP_ECN_send_syn(sk, tp, buff);
+ TCP_ECN_send_syn(sk, buff);
TCP_SKB_CB(buff)->sacked = 0;
- skb_shinfo(buff)->tso_segs = 1;
- skb_shinfo(buff)->tso_size = 0;
+ skb_shinfo(buff)->gso_segs = 1;
+ skb_shinfo(buff)->gso_size = 0;
+ skb_shinfo(buff)->gso_type = 0;
buff->csum = 0;
+ tp->snd_nxt = tp->write_seq;
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;
/* 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);
+ __tcp_add_write_queue_tail(sk, buff);
sk_charge_skb(sk, buff);
tp->packets_out += tcp_skb_pcount(buff);
tcp_transmit_skb(sk, buff, 1, GFP_KERNEL);
+
+ /* We change tp->snd_nxt after the tcp_transmit_skb() call
+ * in order to make this packet get counted in tcpOutSegs.
+ */
+ tp->snd_nxt = tp->write_seq;
+ tp->pushed_seq = tp->write_seq;
TCP_INC_STATS(TCP_MIB_ACTIVEOPENS);
/* Timer for repeating the SYN until an answer. */
{
/* If we have been reset, we may not send again. */
if (sk->sk_state != TCP_CLOSE) {
- struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *buff;
/* We are not putting this on the write queue, so
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;
+ skb_shinfo(buff)->gso_segs = 1;
+ skb_shinfo(buff)->gso_size = 0;
+ skb_shinfo(buff)->gso_type = 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)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk);
TCP_SKB_CB(buff)->when = tcp_time_stamp;
tcp_transmit_skb(sk, buff, 0, GFP_ATOMIC);
}
/* We don't queue it, tcp_transmit_skb() sets ownership. */
skb = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC);
- if (skb == NULL)
+ if (skb == NULL)
return -1;
/* Reserve space for headers and set control bits. */
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;
+ skb_shinfo(skb)->gso_segs = 1;
+ skb_shinfo(skb)->gso_size = 0;
+ skb_shinfo(skb)->gso_type = 0;
/* Use a previous sequence. This should cause the other
* end to send an ack. Don't queue or clone SKB, just
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
- if ((skb = sk->sk_send_head) != NULL &&
+ if ((skb = tcp_send_head(sk)) != NULL &&
before(TCP_SKB_CB(skb)->seq, tp->snd_una+tp->snd_wnd)) {
int err;
unsigned int mss = tcp_current_mss(sk, 0);
TCP_SKB_CB(skb)->when = tcp_time_stamp;
err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
if (!err) {
- update_send_head(sk, tp, skb);
+ update_send_head(sk, skb);
}
return err;
} else {
err = tcp_write_wakeup(sk);
- if (tp->packets_out || !sk->sk_send_head) {
+ if (tp->packets_out || !tcp_send_head(sk)) {
/* Cancel probe timer, if it is not required. */
icsk->icsk_probes_out = 0;
icsk->icsk_backoff = 0;
if (icsk->icsk_backoff < sysctl_tcp_retries2)
icsk->icsk_backoff++;
icsk->icsk_probes_out++;
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
min(icsk->icsk_rto << icsk->icsk_backoff, TCP_RTO_MAX),
TCP_RTO_MAX);
} else {
*/
if (!icsk->icsk_probes_out)
icsk->icsk_probes_out = 1;
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
+ 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_simple_retransmit);
EXPORT_SYMBOL(tcp_sync_mss);
EXPORT_SYMBOL(sysctl_tcp_tso_win_divisor);
+EXPORT_SYMBOL(tcp_mtup_init);