1 /* 2 * Copyright (c) 2006 Oracle. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 * 32 */ 33 #include <linux/kernel.h> 34 #include <linux/gfp.h> 35 #include <linux/in.h> 36 #include <net/tcp.h> 37 38 #include "rds.h" 39 #include "tcp.h" 40 41 int rds_tcp_keepalive(struct socket *sock) 42 { 43 /* values below based on xs_udp_default_timeout */ 44 int keepidle = 5; /* send a probe 'keepidle' secs after last data */ 45 int keepcnt = 5; /* number of unack'ed probes before declaring dead */ 46 int keepalive = 1; 47 int ret = 0; 48 49 ret = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, 50 (char *)&keepalive, sizeof(keepalive)); 51 if (ret < 0) 52 goto bail; 53 54 ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT, 55 (char *)&keepcnt, sizeof(keepcnt)); 56 if (ret < 0) 57 goto bail; 58 59 ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPIDLE, 60 (char *)&keepidle, sizeof(keepidle)); 61 if (ret < 0) 62 goto bail; 63 64 /* KEEPINTVL is the interval between successive probes. We follow 65 * the model in xs_tcp_finish_connecting() and re-use keepidle. 66 */ 67 ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPINTVL, 68 (char *)&keepidle, sizeof(keepidle)); 69 bail: 70 return ret; 71 } 72 73 int rds_tcp_accept_one(struct socket *sock) 74 { 75 struct socket *new_sock = NULL; 76 struct rds_connection *conn; 77 int ret; 78 struct inet_sock *inet; 79 struct rds_tcp_connection *rs_tcp; 80 81 ret = sock_create_kern(sock_net(sock->sk), sock->sk->sk_family, 82 sock->sk->sk_type, sock->sk->sk_protocol, 83 &new_sock); 84 if (ret) 85 goto out; 86 87 new_sock->type = sock->type; 88 new_sock->ops = sock->ops; 89 ret = sock->ops->accept(sock, new_sock, O_NONBLOCK); 90 if (ret < 0) 91 goto out; 92 93 ret = rds_tcp_keepalive(new_sock); 94 if (ret < 0) 95 goto out; 96 97 rds_tcp_tune(new_sock); 98 99 inet = inet_sk(new_sock->sk); 100 101 rdsdebug("accepted tcp %pI4:%u -> %pI4:%u\n", 102 &inet->inet_saddr, ntohs(inet->inet_sport), 103 &inet->inet_daddr, ntohs(inet->inet_dport)); 104 105 conn = rds_conn_create(sock_net(sock->sk), 106 inet->inet_saddr, inet->inet_daddr, 107 &rds_tcp_transport, GFP_KERNEL); 108 if (IS_ERR(conn)) { 109 ret = PTR_ERR(conn); 110 goto out; 111 } 112 /* An incoming SYN request came in, and TCP just accepted it. 113 * 114 * If the client reboots, this conn will need to be cleaned up. 115 * rds_tcp_state_change() will do that cleanup 116 */ 117 rs_tcp = (struct rds_tcp_connection *)conn->c_transport_data; 118 if (rs_tcp->t_sock && 119 ntohl(inet->inet_saddr) < ntohl(inet->inet_daddr)) { 120 struct sock *nsk = new_sock->sk; 121 122 nsk->sk_user_data = NULL; 123 nsk->sk_prot->disconnect(nsk, 0); 124 tcp_done(nsk); 125 new_sock = NULL; 126 ret = 0; 127 goto out; 128 } else if (rs_tcp->t_sock) { 129 rds_tcp_restore_callbacks(rs_tcp->t_sock, rs_tcp); 130 conn->c_outgoing = 0; 131 } 132 133 rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING); 134 rds_tcp_set_callbacks(new_sock, conn); 135 rds_connect_complete(conn); 136 new_sock = NULL; 137 ret = 0; 138 139 out: 140 if (new_sock) 141 sock_release(new_sock); 142 return ret; 143 } 144 145 void rds_tcp_listen_data_ready(struct sock *sk) 146 { 147 void (*ready)(struct sock *sk); 148 149 rdsdebug("listen data ready sk %p\n", sk); 150 151 read_lock(&sk->sk_callback_lock); 152 ready = sk->sk_user_data; 153 if (!ready) { /* check for teardown race */ 154 ready = sk->sk_data_ready; 155 goto out; 156 } 157 158 /* 159 * ->sk_data_ready is also called for a newly established child socket 160 * before it has been accepted and the accepter has set up their 161 * data_ready.. we only want to queue listen work for our listening 162 * socket 163 */ 164 if (sk->sk_state == TCP_LISTEN) 165 rds_tcp_accept_work(sk); 166 167 out: 168 read_unlock(&sk->sk_callback_lock); 169 ready(sk); 170 } 171 172 struct socket *rds_tcp_listen_init(struct net *net) 173 { 174 struct sockaddr_in sin; 175 struct socket *sock = NULL; 176 int ret; 177 178 ret = sock_create_kern(net, PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock); 179 if (ret < 0) 180 goto out; 181 182 sock->sk->sk_reuse = SK_CAN_REUSE; 183 rds_tcp_nonagle(sock); 184 185 write_lock_bh(&sock->sk->sk_callback_lock); 186 sock->sk->sk_user_data = sock->sk->sk_data_ready; 187 sock->sk->sk_data_ready = rds_tcp_listen_data_ready; 188 write_unlock_bh(&sock->sk->sk_callback_lock); 189 190 sin.sin_family = PF_INET; 191 sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY); 192 sin.sin_port = (__force u16)htons(RDS_TCP_PORT); 193 194 ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin)); 195 if (ret < 0) 196 goto out; 197 198 ret = sock->ops->listen(sock, 64); 199 if (ret < 0) 200 goto out; 201 202 return sock; 203 out: 204 if (sock) 205 sock_release(sock); 206 return NULL; 207 } 208 209 void rds_tcp_listen_stop(struct socket *sock) 210 { 211 struct sock *sk; 212 213 if (!sock) 214 return; 215 216 sk = sock->sk; 217 218 /* serialize with and prevent further callbacks */ 219 lock_sock(sk); 220 write_lock_bh(&sk->sk_callback_lock); 221 if (sk->sk_user_data) { 222 sk->sk_data_ready = sk->sk_user_data; 223 sk->sk_user_data = NULL; 224 } 225 write_unlock_bh(&sk->sk_callback_lock); 226 release_sock(sk); 227 228 /* wait for accepts to stop and close the socket */ 229 flush_workqueue(rds_wq); 230 sock_release(sock); 231 } 232