From 50717a37db032ce783f50685a73bb2ac68471a5a Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Fri, 12 Apr 2019 12:57:23 +0200 Subject: [PATCH] net/smc: nonblocking connect rework For nonblocking sockets move the kernel_connect() from the connect worker into the initial smc_connect part to return kernel_connect() errors other than -EINPROGRESS to user space. Reviewed-by: Karsten Graul Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/af_smc.c | 76 ++++++++++++++++++++++++++---------------------- net/smc/smc.h | 11 +++---- 2 files changed, 46 insertions(+), 41 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 77ef53596d18..e1b7b5bdb440 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -134,11 +134,9 @@ static int smc_release(struct socket *sock) smc = smc_sk(sk); /* cleanup for a dangling non-blocking connect */ - if (smc->connect_info && sk->sk_state == SMC_INIT) + if (smc->connect_nonblock && sk->sk_state == SMC_INIT) tcp_abort(smc->clcsock->sk, ECONNABORTED); flush_work(&smc->connect_work); - kfree(smc->connect_info); - smc->connect_info = NULL; if (sk->sk_state == SMC_LISTEN) /* smc_close_non_accepted() is called and acquires @@ -452,6 +450,7 @@ static int smc_connect_fallback(struct smc_sock *smc, int reason_code) smc->use_fallback = true; smc->fallback_rsn = reason_code; smc_copy_sock_settings_to_clc(smc); + smc->connect_nonblock = 0; if (smc->sk.sk_state == SMC_INIT) smc->sk.sk_state = SMC_ACTIVE; return 0; @@ -491,6 +490,7 @@ static int smc_connect_abort(struct smc_sock *smc, int reason_code, mutex_unlock(&smc_client_lgr_pending); smc_conn_free(&smc->conn); + smc->connect_nonblock = 0; return reason_code; } @@ -633,6 +633,7 @@ static int smc_connect_rdma(struct smc_sock *smc, mutex_unlock(&smc_client_lgr_pending); smc_copy_sock_settings_to_clc(smc); + smc->connect_nonblock = 0; if (smc->sk.sk_state == SMC_INIT) smc->sk.sk_state = SMC_ACTIVE; @@ -671,6 +672,7 @@ static int smc_connect_ism(struct smc_sock *smc, mutex_unlock(&smc_server_lgr_pending); smc_copy_sock_settings_to_clc(smc); + smc->connect_nonblock = 0; if (smc->sk.sk_state == SMC_INIT) smc->sk.sk_state = SMC_ACTIVE; @@ -756,17 +758,30 @@ static void smc_connect_work(struct work_struct *work) { struct smc_sock *smc = container_of(work, struct smc_sock, connect_work); - int rc; + long timeo = smc->sk.sk_sndtimeo; + int rc = 0; - lock_sock(&smc->sk); - rc = kernel_connect(smc->clcsock, &smc->connect_info->addr, - smc->connect_info->alen, smc->connect_info->flags); + if (!timeo) + timeo = MAX_SCHEDULE_TIMEOUT; + lock_sock(smc->clcsock->sk); if (smc->clcsock->sk->sk_err) { smc->sk.sk_err = smc->clcsock->sk->sk_err; - goto out; + } else if ((1 << smc->clcsock->sk->sk_state) & + (TCPF_SYN_SENT | TCP_SYN_RECV)) { + rc = sk_stream_wait_connect(smc->clcsock->sk, &timeo); + if ((rc == -EPIPE) && + ((1 << smc->clcsock->sk->sk_state) & + (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT))) + rc = 0; } - if (rc < 0) { - smc->sk.sk_err = -rc; + release_sock(smc->clcsock->sk); + lock_sock(&smc->sk); + if (rc != 0 || smc->sk.sk_err) { + smc->sk.sk_state = SMC_CLOSED; + if (rc == -EPIPE || rc == -EAGAIN) + smc->sk.sk_err = EPIPE; + else if (signal_pending(current)) + smc->sk.sk_err = -sock_intr_errno(timeo); goto out; } @@ -779,8 +794,6 @@ static void smc_connect_work(struct work_struct *work) smc->sk.sk_state_change(&smc->sk); else smc->sk.sk_write_space(&smc->sk); - kfree(smc->connect_info); - smc->connect_info = NULL; release_sock(&smc->sk); } @@ -813,26 +826,18 @@ static int smc_connect(struct socket *sock, struct sockaddr *addr, smc_copy_sock_settings_to_clc(smc); tcp_sk(smc->clcsock->sk)->syn_smc = 1; + if (smc->connect_nonblock) { + rc = -EALREADY; + goto out; + } + rc = kernel_connect(smc->clcsock, addr, alen, flags); + if (rc && rc != -EINPROGRESS) + goto out; if (flags & O_NONBLOCK) { - if (smc->connect_info) { - rc = -EALREADY; - goto out; - } - smc->connect_info = kzalloc(alen + 2 * sizeof(int), GFP_KERNEL); - if (!smc->connect_info) { - rc = -ENOMEM; - goto out; - } - smc->connect_info->alen = alen; - smc->connect_info->flags = flags ^ O_NONBLOCK; - memcpy(&smc->connect_info->addr, addr, alen); - schedule_work(&smc->connect_work); + if (schedule_work(&smc->connect_work)) + smc->connect_nonblock = 1; rc = -EINPROGRESS; } else { - rc = kernel_connect(smc->clcsock, addr, alen, flags); - if (rc) - goto out; - rc = __smc_connect(smc); if (rc < 0) goto out; @@ -1571,8 +1576,8 @@ static __poll_t smc_poll(struct file *file, struct socket *sock, poll_table *wait) { struct sock *sk = sock->sk; - __poll_t mask = 0; struct smc_sock *smc; + __poll_t mask = 0; if (!sk) return EPOLLNVAL; @@ -1582,8 +1587,6 @@ static __poll_t smc_poll(struct file *file, struct socket *sock, /* delegate to CLC child sock */ mask = smc->clcsock->ops->poll(file, smc->clcsock, wait); sk->sk_err = smc->clcsock->sk->sk_err; - if (sk->sk_err) - mask |= EPOLLERR; } else { if (sk->sk_state != SMC_CLOSED) sock_poll_wait(file, sock, wait); @@ -1594,9 +1597,14 @@ static __poll_t smc_poll(struct file *file, struct socket *sock, mask |= EPOLLHUP; if (sk->sk_state == SMC_LISTEN) { /* woken up by sk_data_ready in smc_listen_work() */ - mask = smc_accept_poll(sk); + mask |= smc_accept_poll(sk); + } else if (smc->use_fallback) { /* as result of connect_work()*/ + mask |= smc->clcsock->ops->poll(file, smc->clcsock, + wait); + sk->sk_err = smc->clcsock->sk->sk_err; } else { - if (atomic_read(&smc->conn.sndbuf_space) || + if ((sk->sk_state != SMC_INIT && + atomic_read(&smc->conn.sndbuf_space)) || sk->sk_shutdown & SEND_SHUTDOWN) { mask |= EPOLLOUT | EPOLLWRNORM; } else { diff --git a/net/smc/smc.h b/net/smc/smc.h index adbdf195eb08..878313f8d6c1 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -190,18 +190,11 @@ struct smc_connection { u64 peer_token; /* SMC-D token of peer */ }; -struct smc_connect_info { - int flags; - int alen; - struct sockaddr addr; -}; - struct smc_sock { /* smc sock container */ struct sock sk; struct socket *clcsock; /* internal tcp socket */ struct smc_connection conn; /* smc connection */ struct smc_sock *listen_smc; /* listen parent */ - struct smc_connect_info *connect_info; /* connect address & flags */ struct work_struct connect_work; /* handle non-blocking connect*/ struct work_struct tcp_listen_work;/* handle tcp socket accepts */ struct work_struct smc_listen_work;/* prepare new accept socket */ @@ -219,6 +212,10 @@ struct smc_sock { /* smc sock container */ * started, waiting for unsent * data to be sent */ + u8 connect_nonblock : 1; + /* non-blocking connect in + * flight + */ struct mutex clcsock_release_lock; /* protects clcsock of a listen * socket