tcp: remove one indentation level in tcp_rcv_state_process()

Remove one level of indentation 'introduced' in commit
c3ae62af8e (tcp: should drop incoming frames without ACK flag set)

if (true) {
        ...
}

@acceptable variable is a boolean.

This patch is a pure cleanup.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2013-05-24 15:03:54 +00:00 committed by David S. Miller
parent 42e52bf9e3
commit 1f6afc8108

View File

@ -5536,6 +5536,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
struct inet_connection_sock *icsk = inet_csk(sk);
struct request_sock *req;
int queued = 0;
bool acceptable;
tp->rx_opt.saw_tstamp = 0;
@ -5606,157 +5607,153 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
return 0;
/* step 5: check the ACK field */
if (true) {
int acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH |
FLAG_UPDATE_TS_RECENT) > 0;
acceptable = tcp_ack(sk, skb, FLAG_SLOWPATH |
FLAG_UPDATE_TS_RECENT) > 0;
switch (sk->sk_state) {
case TCP_SYN_RECV:
if (acceptable) {
/* Once we leave TCP_SYN_RECV, we no longer
* need req so release it.
*/
if (req) {
tcp_synack_rtt_meas(sk, req);
tp->total_retrans = req->num_retrans;
reqsk_fastopen_remove(sk, req, false);
} else {
/* Make sure socket is routed, for
* correct metrics.
*/
icsk->icsk_af_ops->rebuild_header(sk);
tcp_init_congestion_control(sk);
tcp_mtup_init(sk);
tcp_init_buffer_space(sk);
tp->copied_seq = tp->rcv_nxt;
}
smp_mb();
tcp_set_state(sk, TCP_ESTABLISHED);
sk->sk_state_change(sk);
/* Note, that this wakeup is only for marginal
* crossed SYN case. Passively open sockets
* are not waked up, because sk->sk_sleep ==
* NULL and sk->sk_socket == NULL.
*/
if (sk->sk_socket)
sk_wake_async(sk,
SOCK_WAKE_IO, POLL_OUT);
tp->snd_una = TCP_SKB_CB(skb)->ack_seq;
tp->snd_wnd = ntohs(th->window) <<
tp->rx_opt.snd_wscale;
tcp_init_wl(tp, TCP_SKB_CB(skb)->seq);
if (tp->rx_opt.tstamp_ok)
tp->advmss -= TCPOLEN_TSTAMP_ALIGNED;
if (req) {
/* Re-arm the timer because data may
* have been sent out. This is similar
* to the regular data transmission case
* when new data has just been ack'ed.
*
* (TFO) - we could try to be more
* aggressive and retranmitting any data
* sooner based on when they were sent
* out.
*/
tcp_rearm_rto(sk);
} else
tcp_init_metrics(sk);
/* Prevent spurious tcp_cwnd_restart() on
* first data packet.
*/
tp->lsndtime = tcp_time_stamp;
tcp_initialize_rcv_mss(sk);
tcp_fast_path_on(tp);
} else {
return 1;
}
break;
case TCP_FIN_WAIT1:
/* If we enter the TCP_FIN_WAIT1 state and we are a
* Fast Open socket and this is the first acceptable
* ACK we have received, this would have acknowledged
* our SYNACK so stop the SYNACK timer.
switch (sk->sk_state) {
case TCP_SYN_RECV:
if (acceptable) {
/* Once we leave TCP_SYN_RECV, we no longer
* need req so release it.
*/
if (req != NULL) {
/* Return RST if ack_seq is invalid.
* Note that RFC793 only says to generate a
* DUPACK for it but for TCP Fast Open it seems
* better to treat this case like TCP_SYN_RECV
* above.
*/
if (!acceptable)
return 1;
/* We no longer need the request sock. */
if (req) {
tcp_synack_rtt_meas(sk, req);
tp->total_retrans = req->num_retrans;
reqsk_fastopen_remove(sk, req, false);
tcp_rearm_rto(sk);
} else {
/* Make sure socket is routed, for
* correct metrics.
*/
icsk->icsk_af_ops->rebuild_header(sk);
tcp_init_congestion_control(sk);
tcp_mtup_init(sk);
tcp_init_buffer_space(sk);
tp->copied_seq = tp->rcv_nxt;
}
if (tp->snd_una == tp->write_seq) {
struct dst_entry *dst;
smp_mb();
tcp_set_state(sk, TCP_ESTABLISHED);
sk->sk_state_change(sk);
tcp_set_state(sk, TCP_FIN_WAIT2);
sk->sk_shutdown |= SEND_SHUTDOWN;
/* Note, that this wakeup is only for marginal
* crossed SYN case. Passively open sockets
* are not waked up, because sk->sk_sleep ==
* NULL and sk->sk_socket == NULL.
*/
if (sk->sk_socket)
sk_wake_async(sk, SOCK_WAKE_IO, POLL_OUT);
dst = __sk_dst_get(sk);
if (dst)
dst_confirm(dst);
tp->snd_una = TCP_SKB_CB(skb)->ack_seq;
tp->snd_wnd = ntohs(th->window) <<
tp->rx_opt.snd_wscale;
tcp_init_wl(tp, TCP_SKB_CB(skb)->seq);
if (!sock_flag(sk, SOCK_DEAD))
/* Wake up lingering close() */
sk->sk_state_change(sk);
else {
int tmo;
if (tp->rx_opt.tstamp_ok)
tp->advmss -= TCPOLEN_TSTAMP_ALIGNED;
if (tp->linger2 < 0 ||
(TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&
after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt))) {
tcp_done(sk);
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
return 1;
}
if (req) {
/* Re-arm the timer because data may
* have been sent out. This is similar
* to the regular data transmission case
* when new data has just been ack'ed.
*
* (TFO) - we could try to be more aggressive
* and retransmitting any data sooner based
* on when they are sent out.
*/
tcp_rearm_rto(sk);
} else
tcp_init_metrics(sk);
tmo = tcp_fin_time(sk);
if (tmo > TCP_TIMEWAIT_LEN) {
inet_csk_reset_keepalive_timer(sk, tmo - TCP_TIMEWAIT_LEN);
} else if (th->fin || sock_owned_by_user(sk)) {
/* Bad case. We could lose such FIN otherwise.
* It is not a big problem, but it looks confusing
* and not so rare event. We still can lose it now,
* if it spins in bh_lock_sock(), but it is really
* marginal case.
*/
inet_csk_reset_keepalive_timer(sk, tmo);
} else {
tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
goto discard;
}
/* Prevent spurious tcp_cwnd_restart() on
* first data packet.
*/
tp->lsndtime = tcp_time_stamp;
tcp_initialize_rcv_mss(sk);
tcp_fast_path_on(tp);
} else {
return 1;
}
break;
case TCP_FIN_WAIT1:
/* If we enter the TCP_FIN_WAIT1 state and we are a
* Fast Open socket and this is the first acceptable
* ACK we have received, this would have acknowledged
* our SYNACK so stop the SYNACK timer.
*/
if (req != NULL) {
/* Return RST if ack_seq is invalid.
* Note that RFC793 only says to generate a
* DUPACK for it but for TCP Fast Open it seems
* better to treat this case like TCP_SYN_RECV
* above.
*/
if (!acceptable)
return 1;
/* We no longer need the request sock. */
reqsk_fastopen_remove(sk, req, false);
tcp_rearm_rto(sk);
}
if (tp->snd_una == tp->write_seq) {
struct dst_entry *dst;
tcp_set_state(sk, TCP_FIN_WAIT2);
sk->sk_shutdown |= SEND_SHUTDOWN;
dst = __sk_dst_get(sk);
if (dst)
dst_confirm(dst);
if (!sock_flag(sk, SOCK_DEAD)) {
/* Wake up lingering close() */
sk->sk_state_change(sk);
} else {
int tmo;
if (tp->linger2 < 0 ||
(TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq &&
after(TCP_SKB_CB(skb)->end_seq - th->fin, tp->rcv_nxt))) {
tcp_done(sk);
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
return 1;
}
tmo = tcp_fin_time(sk);
if (tmo > TCP_TIMEWAIT_LEN) {
inet_csk_reset_keepalive_timer(sk, tmo - TCP_TIMEWAIT_LEN);
} else if (th->fin || sock_owned_by_user(sk)) {
/* Bad case. We could lose such FIN otherwise.
* It is not a big problem, but it looks confusing
* and not so rare event. We still can lose it now,
* if it spins in bh_lock_sock(), but it is really
* marginal case.
*/
inet_csk_reset_keepalive_timer(sk, tmo);
} else {
tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
goto discard;
}
}
break;
case TCP_CLOSING:
if (tp->snd_una == tp->write_seq) {
tcp_time_wait(sk, TCP_TIME_WAIT, 0);
goto discard;
}
break;
case TCP_LAST_ACK:
if (tp->snd_una == tp->write_seq) {
tcp_update_metrics(sk);
tcp_done(sk);
goto discard;
}
break;
}
break;
case TCP_CLOSING:
if (tp->snd_una == tp->write_seq) {
tcp_time_wait(sk, TCP_TIME_WAIT, 0);
goto discard;
}
break;
case TCP_LAST_ACK:
if (tp->snd_una == tp->write_seq) {
tcp_update_metrics(sk);
tcp_done(sk);
goto discard;
}
break;
}
/* step 6: check the URG bit */