diff options
| -rw-r--r-- | net/smc/af_smc.c | 45 | ||||
| -rw-r--r-- | net/smc/smc.h | 6 |
2 files changed, 50 insertions, 1 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 4969ac8029a9..858724256078 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -73,6 +73,36 @@ static void smc_set_keepalive(struct sock *sk, int val) smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val); } +static struct sock *smc_tcp_syn_recv_sock(const struct sock *sk, + struct sk_buff *skb, + struct request_sock *req, + struct dst_entry *dst, + struct request_sock *req_unhash, + bool *own_req) +{ + struct smc_sock *smc; + + smc = smc_clcsock_user_data(sk); + + if (READ_ONCE(sk->sk_ack_backlog) + atomic_read(&smc->queued_smc_hs) > + sk->sk_max_ack_backlog) + goto drop; + + if (sk_acceptq_is_full(&smc->sk)) { + NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS); + goto drop; + } + + /* passthrough to original syn recv sock fct */ + return smc->ori_af_ops->syn_recv_sock(sk, skb, req, dst, req_unhash, + own_req); + +drop: + dst_release(dst); + tcp_listendrop(sk); + return NULL; +} + static struct smc_hashinfo smc_v4_hashinfo = { .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock), }; @@ -1595,6 +1625,9 @@ static void smc_listen_out(struct smc_sock *new_smc) struct smc_sock *lsmc = new_smc->listen_smc; struct sock *newsmcsk = &new_smc->sk; + if (tcp_sk(new_smc->clcsock->sk)->syn_smc) + atomic_dec(&lsmc->queued_smc_hs); + if (lsmc->sk.sk_state == SMC_LISTEN) { lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING); smc_accept_enqueue(&lsmc->sk, newsmcsk); @@ -2200,6 +2233,9 @@ static void smc_tcp_listen_work(struct work_struct *work) if (!new_smc) continue; + if (tcp_sk(new_smc->clcsock->sk)->syn_smc) + atomic_inc(&lsmc->queued_smc_hs); + new_smc->listen_smc = lsmc; new_smc->use_fallback = lsmc->use_fallback; new_smc->fallback_rsn = lsmc->fallback_rsn; @@ -2266,6 +2302,15 @@ static int smc_listen(struct socket *sock, int backlog) smc->clcsock->sk->sk_data_ready = smc_clcsock_data_ready; smc->clcsock->sk->sk_user_data = (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY); + + /* save original ops */ + smc->ori_af_ops = inet_csk(smc->clcsock->sk)->icsk_af_ops; + + smc->af_ops = *smc->ori_af_ops; + smc->af_ops.syn_recv_sock = smc_tcp_syn_recv_sock; + + inet_csk(smc->clcsock->sk)->icsk_af_ops = &smc->af_ops; + rc = kernel_listen(smc->clcsock, backlog); if (rc) { smc->clcsock->sk->sk_data_ready = smc->clcsk_data_ready; diff --git a/net/smc/smc.h b/net/smc/smc.h index 37b2001a0255..e91e40040d07 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -252,6 +252,10 @@ struct smc_sock { /* smc sock container */ bool use_fallback; /* fallback to tcp */ int fallback_rsn; /* reason for fallback */ u32 peer_diagnosis; /* decline reason from peer */ + atomic_t queued_smc_hs; /* queued smc handshakes */ + struct inet_connection_sock_af_ops af_ops; + const struct inet_connection_sock_af_ops *ori_af_ops; + /* original af ops */ int sockopt_defer_accept; /* sockopt TCP_DEFER_ACCEPT * value @@ -276,7 +280,7 @@ static inline struct smc_sock *smc_sk(const struct sock *sk) return (struct smc_sock *)sk; } -static inline struct smc_sock *smc_clcsock_user_data(struct sock *clcsk) +static inline struct smc_sock *smc_clcsock_user_data(const struct sock *clcsk) { return (struct smc_sock *) ((uintptr_t)clcsk->sk_user_data & ~SK_USER_DATA_NOCOPY); |