diff options
Diffstat (limited to 'net/rds/tcp_listen.c')
| -rw-r--r-- | net/rds/tcp_listen.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c new file mode 100644 index 00000000000..24b743eb0b1 --- /dev/null +++ b/net/rds/tcp_listen.c @@ -0,0 +1,199 @@ +/* + * Copyright (c) 2006 Oracle. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + */ +#include <linux/kernel.h> +#include <linux/in.h> +#include <net/tcp.h> + +#include "rds.h" +#include "tcp.h" + +/* + * cheesy, but simple.. + */ +static void rds_tcp_accept_worker(struct work_struct *work); +static DECLARE_WORK(rds_tcp_listen_work, rds_tcp_accept_worker); +static struct socket *rds_tcp_listen_sock; + +static int rds_tcp_accept_one(struct socket *sock) +{ + struct socket *new_sock = NULL; + struct rds_connection *conn; + int ret; + struct inet_sock *inet; + + ret = sock_create_lite(sock->sk->sk_family, sock->sk->sk_type, + sock->sk->sk_protocol, &new_sock); + if (ret) + goto out; + + new_sock->type = sock->type; + new_sock->ops = sock->ops; + ret = sock->ops->accept(sock, new_sock, O_NONBLOCK); + if (ret < 0) + goto out; + + rds_tcp_tune(new_sock); + + inet = inet_sk(new_sock->sk); + + rdsdebug("accepted tcp %u.%u.%u.%u:%u -> %u.%u.%u.%u:%u\n", + NIPQUAD(inet->saddr), ntohs(inet->sport), + NIPQUAD(inet->daddr), ntohs(inet->dport)); + + conn = rds_conn_create(inet->saddr, inet->daddr, &rds_tcp_transport, + GFP_KERNEL); + if (IS_ERR(conn)) { + ret = PTR_ERR(conn); + goto out; + } + + /* + * see the comment above rds_queue_delayed_reconnect() + */ + if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) { + if (rds_conn_state(conn) == RDS_CONN_UP) + rds_tcp_stats_inc(s_tcp_listen_closed_stale); + else + rds_tcp_stats_inc(s_tcp_connect_raced); + rds_conn_drop(conn); + ret = 0; + goto out; + } + + rds_tcp_set_callbacks(new_sock, conn); + rds_connect_complete(conn); + new_sock = NULL; + ret = 0; + +out: + if (new_sock) + sock_release(new_sock); + return ret; +} + +static void rds_tcp_accept_worker(struct work_struct *work) +{ + while (rds_tcp_accept_one(rds_tcp_listen_sock) == 0) + cond_resched(); +} + +void rds_tcp_listen_data_ready(struct sock *sk, int bytes) +{ + void (*ready)(struct sock *sk, int bytes); + + rdsdebug("listen data ready sk %p\n", sk); + + read_lock(&sk->sk_callback_lock); + ready = sk->sk_user_data; + if (ready == NULL) { /* check for teardown race */ + ready = sk->sk_data_ready; + goto out; + } + + /* + * ->sk_data_ready is also called for a newly established child socket + * before it has been accepted and the accepter has set up their + * data_ready.. we only want to queue listen work for our listening + * socket + */ + if (sk->sk_state == TCP_LISTEN) + queue_work(rds_wq, &rds_tcp_listen_work); + +out: + read_unlock(&sk->sk_callback_lock); + ready(sk, bytes); +} + +int __init rds_tcp_listen_init(void) +{ + struct sockaddr_in sin; + struct socket *sock = NULL; + int ret; + + ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock); + if (ret < 0) + goto out; + + sock->sk->sk_reuse = 1; + rds_tcp_nonagle(sock); + + write_lock_bh(&sock->sk->sk_callback_lock); + sock->sk->sk_user_data = sock->sk->sk_data_ready; + sock->sk->sk_data_ready = rds_tcp_listen_data_ready; + write_unlock_bh(&sock->sk->sk_callback_lock); + + sin.sin_family = PF_INET, + sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY); + sin.sin_port = (__force u16)htons(RDS_TCP_PORT); + + ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin)); + if (ret < 0) + goto out; + + ret = sock->ops->listen(sock, 64); + if (ret < 0) + goto out; + + rds_tcp_listen_sock = sock; + sock = NULL; +out: + if (sock) + sock_release(sock); + return ret; +} + +void rds_tcp_listen_stop(void) +{ + struct socket *sock = rds_tcp_listen_sock; + struct sock *sk; + + if (sock == NULL) + return; + + sk = sock->sk; + + /* serialize with and prevent further callbacks */ + lock_sock(sk); + write_lock_bh(&sk->sk_callback_lock); + if (sk->sk_user_data) { + sk->sk_data_ready = sk->sk_user_data; + sk->sk_user_data = NULL; + } + write_unlock_bh(&sk->sk_callback_lock); + release_sock(sk); + + /* wait for accepts to stop and close the socket */ + flush_workqueue(rds_wq); + sock_release(sock); + rds_tcp_listen_sock = NULL; +} |