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Diffstat (limited to 'net/ipv4/tcp_input.c')
-rw-r--r--net/ipv4/tcp_input.c86
1 files changed, 39 insertions, 47 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 548d575e6cc6..3357f69e353d 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -78,10 +78,13 @@ int sysctl_tcp_window_scaling __read_mostly = 1;
int sysctl_tcp_sack __read_mostly = 1;
int sysctl_tcp_fack __read_mostly = 1;
int sysctl_tcp_reordering __read_mostly = TCP_FASTRETRANS_THRESH;
+EXPORT_SYMBOL(sysctl_tcp_reordering);
int sysctl_tcp_ecn __read_mostly = 2;
+EXPORT_SYMBOL(sysctl_tcp_ecn);
int sysctl_tcp_dsack __read_mostly = 1;
int sysctl_tcp_app_win __read_mostly = 31;
int sysctl_tcp_adv_win_scale __read_mostly = 2;
+EXPORT_SYMBOL(sysctl_tcp_adv_win_scale);
int sysctl_tcp_stdurg __read_mostly;
int sysctl_tcp_rfc1337 __read_mostly;
@@ -179,7 +182,7 @@ static void tcp_incr_quickack(struct sock *sk)
icsk->icsk_ack.quick = min(quickacks, TCP_MAX_QUICKACKS);
}
-void tcp_enter_quickack_mode(struct sock *sk)
+static void tcp_enter_quickack_mode(struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
tcp_incr_quickack(sk);
@@ -419,15 +422,16 @@ void tcp_initialize_rcv_mss(struct sock *sk)
inet_csk(sk)->icsk_ack.rcv_mss = hint;
}
+EXPORT_SYMBOL(tcp_initialize_rcv_mss);
/* Receiver "autotuning" code.
*
* The algorithm for RTT estimation w/o timestamps is based on
* Dynamic Right-Sizing (DRS) by Wu Feng and Mike Fisk of LANL.
- * <http://www.lanl.gov/radiant/website/pubs/drs/lacsi2001.ps>
+ * <http://public.lanl.gov/radiant/pubs.html#DRS>
*
* More detail on this code can be found at
- * <http://www.psc.edu/~jheffner/senior_thesis.ps>,
+ * <http://staff.psc.edu/jheffner/>,
* though this reference is out of date. A new paper
* is pending.
*/
@@ -801,25 +805,12 @@ void tcp_update_metrics(struct sock *sk)
}
}
-/* Numbers are taken from RFC3390.
- *
- * John Heffner states:
- *
- * The RFC specifies a window of no more than 4380 bytes
- * unless 2*MSS > 4380. Reading the pseudocode in the RFC
- * is a bit misleading because they use a clamp at 4380 bytes
- * rather than use a multiplier in the relevant range.
- */
__u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst)
{
__u32 cwnd = (dst ? dst_metric(dst, RTAX_INITCWND) : 0);
- if (!cwnd) {
- if (tp->mss_cache > 1460)
- cwnd = 2;
- else
- cwnd = (tp->mss_cache > 1095) ? 3 : 4;
- }
+ if (!cwnd)
+ cwnd = rfc3390_bytes_to_packets(tp->mss_cache);
return min_t(__u32, cwnd, tp->snd_cwnd_clamp);
}
@@ -2310,7 +2301,7 @@ static inline int tcp_dupack_heuristics(struct tcp_sock *tp)
static inline int tcp_skb_timedout(struct sock *sk, struct sk_buff *skb)
{
- return (tcp_time_stamp - TCP_SKB_CB(skb)->when > inet_csk(sk)->icsk_rto);
+ return tcp_time_stamp - TCP_SKB_CB(skb)->when > inet_csk(sk)->icsk_rto;
}
static inline int tcp_head_timedout(struct sock *sk)
@@ -2504,7 +2495,7 @@ static void tcp_timeout_skbs(struct sock *sk)
/* Mark head of queue up as lost. With RFC3517 SACK, the packets is
* is against sacked "cnt", otherwise it's against facked "cnt"
*/
-static void tcp_mark_head_lost(struct sock *sk, int packets)
+static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
@@ -2512,13 +2503,13 @@ static void tcp_mark_head_lost(struct sock *sk, int packets)
int err;
unsigned int mss;
- if (packets == 0)
- return;
-
WARN_ON(packets > tp->packets_out);
if (tp->lost_skb_hint) {
skb = tp->lost_skb_hint;
cnt = tp->lost_cnt_hint;
+ /* Head already handled? */
+ if (mark_head && skb != tcp_write_queue_head(sk))
+ return;
} else {
skb = tcp_write_queue_head(sk);
cnt = 0;
@@ -2541,7 +2532,8 @@ static void tcp_mark_head_lost(struct sock *sk, int packets)
cnt += tcp_skb_pcount(skb);
if (cnt > packets) {
- if (tcp_is_sack(tp) || (oldcnt >= packets))
+ if ((tcp_is_sack(tp) && !tcp_is_fack(tp)) ||
+ (oldcnt >= packets))
break;
mss = skb_shinfo(skb)->gso_size;
@@ -2552,6 +2544,9 @@ static void tcp_mark_head_lost(struct sock *sk, int packets)
}
tcp_skb_mark_lost(tp, skb);
+
+ if (mark_head)
+ break;
}
tcp_verify_left_out(tp);
}
@@ -2563,17 +2558,18 @@ static void tcp_update_scoreboard(struct sock *sk, int fast_rexmit)
struct tcp_sock *tp = tcp_sk(sk);
if (tcp_is_reno(tp)) {
- tcp_mark_head_lost(sk, 1);
+ tcp_mark_head_lost(sk, 1, 1);
} else if (tcp_is_fack(tp)) {
int lost = tp->fackets_out - tp->reordering;
if (lost <= 0)
lost = 1;
- tcp_mark_head_lost(sk, lost);
+ tcp_mark_head_lost(sk, lost, 0);
} else {
int sacked_upto = tp->sacked_out - tp->reordering;
- if (sacked_upto < fast_rexmit)
- sacked_upto = fast_rexmit;
- tcp_mark_head_lost(sk, sacked_upto);
+ if (sacked_upto >= 0)
+ tcp_mark_head_lost(sk, sacked_upto, 0);
+ else if (fast_rexmit)
+ tcp_mark_head_lost(sk, 1, 1);
}
tcp_timeout_skbs(sk);
@@ -2882,7 +2878,7 @@ static void tcp_mtup_probe_success(struct sock *sk)
icsk->icsk_mtup.probe_size;
tp->snd_cwnd_cnt = 0;
tp->snd_cwnd_stamp = tcp_time_stamp;
- tp->rcv_ssthresh = tcp_current_ssthresh(sk);
+ tp->snd_ssthresh = tcp_current_ssthresh(sk);
icsk->icsk_mtup.search_low = icsk->icsk_mtup.probe_size;
icsk->icsk_mtup.probe_size = 0;
@@ -2938,6 +2934,7 @@ void tcp_simple_retransmit(struct sock *sk)
}
tcp_xmit_retransmit_queue(sk);
}
+EXPORT_SYMBOL(tcp_simple_retransmit);
/* Process an event, which can update packets-in-flight not trivially.
* Main goal of this function is to calculate new estimate for left_out,
@@ -2978,7 +2975,7 @@ static void tcp_fastretrans_alert(struct sock *sk, int pkts_acked, int flag)
before(tp->snd_una, tp->high_seq) &&
icsk->icsk_ca_state != TCP_CA_Open &&
tp->fackets_out > tp->reordering) {
- tcp_mark_head_lost(sk, tp->fackets_out - tp->reordering);
+ tcp_mark_head_lost(sk, tp->fackets_out - tp->reordering, 0);
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPLOSS);
}
@@ -3286,7 +3283,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
* connection startup slow start one packet too
* quickly. This is severely frowned upon behavior.
*/
- if (!(scb->flags & TCPCB_FLAG_SYN)) {
+ if (!(scb->flags & TCPHDR_SYN)) {
flag |= FLAG_DATA_ACKED;
} else {
flag |= FLAG_SYN_ACKED;
@@ -3406,8 +3403,8 @@ static void tcp_ack_probe(struct sock *sk)
static inline int tcp_ack_is_dubious(const struct sock *sk, const int flag)
{
- return (!(flag & FLAG_NOT_DUP) || (flag & FLAG_CA_ALERT) ||
- inet_csk(sk)->icsk_ca_state != TCP_CA_Open);
+ return !(flag & FLAG_NOT_DUP) || (flag & FLAG_CA_ALERT) ||
+ inet_csk(sk)->icsk_ca_state != TCP_CA_Open;
}
static inline int tcp_may_raise_cwnd(const struct sock *sk, const int flag)
@@ -3424,9 +3421,9 @@ static inline int tcp_may_update_window(const struct tcp_sock *tp,
const u32 ack, const u32 ack_seq,
const u32 nwin)
{
- return (after(ack, tp->snd_una) ||
+ return after(ack, tp->snd_una) ||
after(ack_seq, tp->snd_wl1) ||
- (ack_seq == tp->snd_wl1 && nwin > tp->snd_wnd));
+ (ack_seq == tp->snd_wl1 && nwin > tp->snd_wnd);
}
/* Update our send window.
@@ -3858,6 +3855,7 @@ void tcp_parse_options(struct sk_buff *skb, struct tcp_options_received *opt_rx,
}
}
}
+EXPORT_SYMBOL(tcp_parse_options);
static int tcp_parse_aligned_timestamp(struct tcp_sock *tp, struct tcphdr *th)
{
@@ -3924,13 +3922,14 @@ u8 *tcp_parse_md5sig_option(struct tcphdr *th)
if (opsize < 2 || opsize > length)
return NULL;
if (opcode == TCPOPT_MD5SIG)
- return ptr;
+ return opsize == TCPOLEN_MD5SIG ? ptr : NULL;
}
ptr += opsize - 2;
length -= opsize;
}
return NULL;
}
+EXPORT_SYMBOL(tcp_parse_md5sig_option);
#endif
static inline void tcp_store_ts_recent(struct tcp_sock *tp)
@@ -4041,6 +4040,8 @@ static void tcp_reset(struct sock *sk)
default:
sk->sk_err = ECONNRESET;
}
+ /* This barrier is coupled with smp_rmb() in tcp_poll() */
+ smp_wmb();
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_error_report(sk);
@@ -5432,6 +5433,7 @@ discard:
__kfree_skb(skb);
return 0;
}
+EXPORT_SYMBOL(tcp_rcv_established);
static int tcp_rcv_synsent_state_process(struct sock *sk, struct sk_buff *skb,
struct tcphdr *th, unsigned len)
@@ -5931,14 +5933,4 @@ discard:
}
return 0;
}
-
-EXPORT_SYMBOL(sysctl_tcp_ecn);
-EXPORT_SYMBOL(sysctl_tcp_reordering);
-EXPORT_SYMBOL(sysctl_tcp_adv_win_scale);
-EXPORT_SYMBOL(tcp_parse_options);
-#ifdef CONFIG_TCP_MD5SIG
-EXPORT_SYMBOL(tcp_parse_md5sig_option);
-#endif
-EXPORT_SYMBOL(tcp_rcv_established);
EXPORT_SYMBOL(tcp_rcv_state_process);
-EXPORT_SYMBOL(tcp_initialize_rcv_mss);
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-06-03 14:22:06 +0200