X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=net%2Fipv4%2Ftcp_output.c;h=a7623ead39a8b6a91fe34b81afd5193d9ed6cce3;hb=ab396e91bfe953db26fa1083d9c3e7a4fbe0334a;hp=029c70dfb585f74e74383faf40c1816b4e6d410d;hpb=a9931a6e37c09f6b76a9fa0cbd777c335548692b;p=linux-2.6-omap-h63xx.git diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 029c70dfb58..a7623ead39a 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -51,8 +51,8 @@ int sysctl_tcp_retrans_collapse = 1; */ int sysctl_tcp_tso_win_divisor = 3; -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 tcp_sock *tp, + struct sk_buff *skb) { sk->sk_send_head = skb->next; if (sk->sk_send_head == (struct sk_buff *)&sk->sk_write_queue) @@ -124,8 +124,8 @@ static void tcp_cwnd_restart(struct sock *sk, struct dst_entry *dst) 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; @@ -142,7 +142,7 @@ static inline void tcp_event_data_sent(struct tcp_sock *tp, 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); @@ -212,7 +212,7 @@ void tcp_select_initial_window(int __space, __u32 mss, * 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); @@ -250,6 +250,75 @@ static __inline__ u16 tcp_select_window(struct sock *sk) 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 @@ -262,122 +331,139 @@ static __inline__ u16 tcp_select_window(struct sock *sk) * We are working here with either a clone of the original * SKB, or a fresh unique copy made by the retransmit engine. */ -static 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) { - const struct inet_connection_sock *icsk = inet_csk(sk); - struct inet_sock *inet = inet_sk(sk); - struct tcp_sock *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; + } - BUG_ON(!tcp_skb_pcount(skb)); + 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 - /* If congestion control is doing timestamping */ - if (icsk->icsk_ca_ops->rtt_sample) - __net_timestamp(skb); - - 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->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)); + 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 (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 (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)); + if (sysctl_tcp_window_scaling) { + tcp_header_size += TCPOLEN_WSCALE_ALIGNED; + sysctl_flags |= SYSCTL_FLAG_WSCALE; } - 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 (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 (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. + */ + th->window = htons(tp->rcv_wnd); + } else { + th->window = htons(tcp_select_window(sk)); + } + th->check = 0; + th->urg_ptr = 0; - 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->rx_opt.rcv_wscale, - tcb->when, - tp->rx_opt.ts_recent); - } else { - tcp_build_and_update_options((__u32 *)(th + 1), - tp, tcb->when); + 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; + } - TCP_ECN_send(sk, tp, skb, tcp_header_size); - } - tp->af_specific->send_check(sk, th, skb->len, skb); + 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); + } - if (tcb->flags & TCPCB_FLAG_ACK) - tcp_event_ack_sent(sk, tcp_skb_pcount(skb)); + icsk->icsk_af_ops->send_check(sk, skb->len, skb); - if (skb->len != tcp_header_size) - tcp_event_data_sent(tp, skb, sk); + if (likely(tcb->flags & TCPCB_FLAG_ACK)) + tcp_event_ack_sent(sk, tcp_skb_pcount(skb)); - TCP_INC_STATS(TCP_MIB_OUTSEGS); + if (skb->len != tcp_header_size) + tcp_event_data_sent(tp, skb, sk); - err = tp->af_specific->queue_xmit(skb, 0); - if (err <= 0) - return err; + TCP_INC_STATS(TCP_MIB_OUTSEGS); - tcp_enter_cwr(sk); + err = icsk->icsk_af_ops->queue_xmit(skb, 0); + if (unlikely(err <= 0)) + return err; + + 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 @@ -604,7 +690,7 @@ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len) 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, @@ -614,26 +700,26 @@ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len) 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) */ unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu) { struct tcp_sock *tp = tcp_sk(sk); - int mss_now; - + 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->rx_opt.mss_clamp) mss_now = tp->rx_opt.mss_clamp; /* Now subtract optional transport overhead */ - mss_now -= tp->ext_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) @@ -647,7 +733,7 @@ unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu) mss_now = max((tp->max_window>>1), 68U - tp->tcp_header_len); /* And store cached results */ - tp->pmtu_cookie = pmtu; + icsk->icsk_pmtu_cookie = pmtu; tp->mss_cache = mss_now; return mss_now; @@ -677,7 +763,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed) if (dst) { u32 mtu = dst_mtu(dst); - if (mtu != tp->pmtu_cookie) + if (mtu != inet_csk(sk)->icsk_pmtu_cookie) mss_now = tcp_sync_mss(sk, mtu); } @@ -688,9 +774,10 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed) xmit_size_goal = mss_now; if (doing_tso) { - xmit_size_goal = 65535 - - tp->af_specific->net_header_len - - tp->ext_header_len - tp->tcp_header_len; + xmit_size_goal = (65535 - + inet_csk(sk)->icsk_af_ops->net_header_len - + inet_csk(sk)->icsk_ext_hdr_len - + tp->tcp_header_len); if (tp->max_window && (xmit_size_goal > (tp->max_window >> 1))) @@ -706,7 +793,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed) /* 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) { __u32 packets_out = tp->packets_out; @@ -755,7 +842,7 @@ static inline unsigned int tcp_cwnd_test(struct tcp_sock *tp, struct sk_buff *sk /* 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); @@ -1036,7 +1123,7 @@ static int tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle) TCP_SKB_CB(skb)->when = tcp_time_stamp; - if (unlikely(tcp_transmit_skb(sk, skb_clone(skb, GFP_ATOMIC)))) + if (unlikely(tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC))) break; /* Advance the send_head. This one is sent out. @@ -1109,7 +1196,7 @@ void tcp_push_one(struct sock *sk, unsigned int mss_now) /* Send it out now. */ TCP_SKB_CB(skb)->when = tcp_time_stamp; - if (likely(!tcp_transmit_skb(sk, skb_clone(skb, sk->sk_allocation)))) { + if (likely(!tcp_transmit_skb(sk, skb, 1, sk->sk_allocation))) { update_send_head(sk, tp, skb); tcp_cwnd_validate(sk, tp); return; @@ -1405,7 +1492,7 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb) (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 @@ -1429,9 +1516,7 @@ int tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb) */ 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. */ @@ -1665,7 +1750,7 @@ void tcp_send_active_reset(struct sock *sk, gfp_t priority) 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)) + if (tcp_transmit_skb(sk, skb, 0, priority)) NET_INC_STATS(LINUX_MIB_TCPABORTFAILED); } @@ -1700,7 +1785,7 @@ int tcp_send_synack(struct sock *sk) 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); } /* @@ -1778,7 +1863,7 @@ struct sk_buff * tcp_make_synack(struct sock *sk, struct dst_entry *dst, /* * 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); @@ -1861,7 +1946,7 @@ int tcp_connect(struct sock *sk) __skb_queue_tail(&sk->sk_write_queue, buff); sk_charge_skb(sk, buff); tp->packets_out += tcp_skb_pcount(buff); - tcp_transmit_skb(sk, skb_clone(buff, GFP_KERNEL)); + tcp_transmit_skb(sk, buff, 1, GFP_KERNEL); TCP_INC_STATS(TCP_MIB_ACTIVEOPENS); /* Timer for repeating the SYN until an answer. */ @@ -1957,7 +2042,7 @@ void tcp_send_ack(struct sock *sk) /* 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); } } @@ -1997,7 +2082,7 @@ static int tcp_xmit_probe_skb(struct sock *sk, int urgent) 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) @@ -2030,7 +2115,7 @@ int tcp_write_wakeup(struct sock *sk) 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); }