diff options
Diffstat (limited to 'net/smc')
| -rw-r--r-- | net/smc/af_smc.c | 133 | ||||
| -rw-r--r-- | net/smc/smc.h | 20 |
2 files changed, 137 insertions, 16 deletions
diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index d5ea62b82bb8..8c89d0b0ca18 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -566,17 +566,115 @@ static void smc_stat_fallback(struct smc_sock *smc) mutex_unlock(&net->smc.mutex_fback_rsn); } +/* must be called under rcu read lock */ +static void smc_fback_wakeup_waitqueue(struct smc_sock *smc, void *key) +{ + struct socket_wq *wq; + __poll_t flags; + + wq = rcu_dereference(smc->sk.sk_wq); + if (!skwq_has_sleeper(wq)) + return; + + /* wake up smc sk->sk_wq */ + if (!key) { + /* sk_state_change */ + wake_up_interruptible_all(&wq->wait); + } else { + flags = key_to_poll(key); + if (flags & (EPOLLIN | EPOLLOUT)) + /* sk_data_ready or sk_write_space */ + wake_up_interruptible_sync_poll(&wq->wait, flags); + else if (flags & EPOLLERR) + /* sk_error_report */ + wake_up_interruptible_poll(&wq->wait, flags); + } +} + +static int smc_fback_mark_woken(wait_queue_entry_t *wait, + unsigned int mode, int sync, void *key) +{ + struct smc_mark_woken *mark = + container_of(wait, struct smc_mark_woken, wait_entry); + + mark->woken = true; + mark->key = key; + return 0; +} + +static void smc_fback_forward_wakeup(struct smc_sock *smc, struct sock *clcsk, + void (*clcsock_callback)(struct sock *sk)) +{ + struct smc_mark_woken mark = { .woken = false }; + struct socket_wq *wq; + + init_waitqueue_func_entry(&mark.wait_entry, + smc_fback_mark_woken); + rcu_read_lock(); + wq = rcu_dereference(clcsk->sk_wq); + if (!wq) + goto out; + add_wait_queue(sk_sleep(clcsk), &mark.wait_entry); + clcsock_callback(clcsk); + remove_wait_queue(sk_sleep(clcsk), &mark.wait_entry); + + if (mark.woken) + smc_fback_wakeup_waitqueue(smc, mark.key); +out: + rcu_read_unlock(); +} + +static void smc_fback_state_change(struct sock *clcsk) +{ + struct smc_sock *smc = + smc_clcsock_user_data(clcsk); + + if (!smc) + return; + smc_fback_forward_wakeup(smc, clcsk, smc->clcsk_state_change); +} + +static void smc_fback_data_ready(struct sock *clcsk) +{ + struct smc_sock *smc = + smc_clcsock_user_data(clcsk); + + if (!smc) + return; + smc_fback_forward_wakeup(smc, clcsk, smc->clcsk_data_ready); +} + +static void smc_fback_write_space(struct sock *clcsk) +{ + struct smc_sock *smc = + smc_clcsock_user_data(clcsk); + + if (!smc) + return; + smc_fback_forward_wakeup(smc, clcsk, smc->clcsk_write_space); +} + +static void smc_fback_error_report(struct sock *clcsk) +{ + struct smc_sock *smc = + smc_clcsock_user_data(clcsk); + + if (!smc) + return; + smc_fback_forward_wakeup(smc, clcsk, smc->clcsk_error_report); +} + static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code) { - wait_queue_head_t *smc_wait = sk_sleep(&smc->sk); - wait_queue_head_t *clc_wait; - unsigned long flags; + struct sock *clcsk; mutex_lock(&smc->clcsock_release_lock); if (!smc->clcsock) { mutex_unlock(&smc->clcsock_release_lock); return -EBADF; } + clcsk = smc->clcsock->sk; + smc->use_fallback = true; smc->fallback_rsn = reason_code; smc_stat_fallback(smc); @@ -587,16 +685,22 @@ static int smc_switch_to_fallback(struct smc_sock *smc, int reason_code) smc->clcsock->wq.fasync_list = smc->sk.sk_socket->wq.fasync_list; - /* There may be some entries remaining in - * smc socket->wq, which should be removed - * to clcsocket->wq during the fallback. + /* There might be some wait entries remaining + * in smc sk->sk_wq and they should be woken up + * as clcsock's wait queue is woken up. */ - clc_wait = sk_sleep(smc->clcsock->sk); - spin_lock_irqsave(&smc_wait->lock, flags); - spin_lock_nested(&clc_wait->lock, SINGLE_DEPTH_NESTING); - list_splice_init(&smc_wait->head, &clc_wait->head); - spin_unlock(&clc_wait->lock); - spin_unlock_irqrestore(&smc_wait->lock, flags); + smc->clcsk_state_change = clcsk->sk_state_change; + smc->clcsk_data_ready = clcsk->sk_data_ready; + smc->clcsk_write_space = clcsk->sk_write_space; + smc->clcsk_error_report = clcsk->sk_error_report; + + clcsk->sk_state_change = smc_fback_state_change; + clcsk->sk_data_ready = smc_fback_data_ready; + clcsk->sk_write_space = smc_fback_write_space; + clcsk->sk_error_report = smc_fback_error_report; + + smc->clcsock->sk->sk_user_data = + (void *)((uintptr_t)smc | SK_USER_DATA_NOCOPY); } mutex_unlock(&smc->clcsock_release_lock); return 0; @@ -2115,10 +2219,9 @@ out: static void smc_clcsock_data_ready(struct sock *listen_clcsock) { - struct smc_sock *lsmc; + struct smc_sock *lsmc = + smc_clcsock_user_data(listen_clcsock); - lsmc = (struct smc_sock *) - ((uintptr_t)listen_clcsock->sk_user_data & ~SK_USER_DATA_NOCOPY); if (!lsmc) return; lsmc->clcsk_data_ready(listen_clcsock); diff --git a/net/smc/smc.h b/net/smc/smc.h index 3d0b8e300deb..37b2001a0255 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -139,6 +139,12 @@ enum smc_urg_state { SMC_URG_READ = 3, /* data was already read */ }; +struct smc_mark_woken { + bool woken; + void *key; + wait_queue_entry_t wait_entry; +}; + struct smc_connection { struct rb_node alert_node; struct smc_link_group *lgr; /* link group of connection */ @@ -228,8 +234,14 @@ struct smc_connection { struct smc_sock { /* smc sock container */ struct sock sk; struct socket *clcsock; /* internal tcp socket */ + void (*clcsk_state_change)(struct sock *sk); + /* original stat_change fct. */ void (*clcsk_data_ready)(struct sock *sk); - /* original data_ready fct. **/ + /* original data_ready fct. */ + void (*clcsk_write_space)(struct sock *sk); + /* original write_space fct. */ + void (*clcsk_error_report)(struct sock *sk); + /* original error_report fct. */ struct smc_connection conn; /* smc connection */ struct smc_sock *listen_smc; /* listen parent */ struct work_struct connect_work; /* handle non-blocking connect*/ @@ -264,6 +276,12 @@ 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) +{ + return (struct smc_sock *) + ((uintptr_t)clcsk->sk_user_data & ~SK_USER_DATA_NOCOPY); +} + extern struct workqueue_struct *smc_hs_wq; /* wq for handshake work */ extern struct workqueue_struct *smc_close_wq; /* wq for close work */ |