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/in.h> 35 #include <net/tcp.h> 36 37 #include "rds.h" 38 #include "tcp.h" 39 40 void rds_tcp_state_change(struct sock *sk) 41 { 42 void (*state_change)(struct sock *sk); 43 struct rds_conn_path *cp; 44 struct rds_tcp_connection *tc; 45 46 read_lock_bh(&sk->sk_callback_lock); 47 cp = sk->sk_user_data; 48 if (!cp) { 49 state_change = sk->sk_state_change; 50 goto out; 51 } 52 tc = cp->cp_transport_data; 53 state_change = tc->t_orig_state_change; 54 55 rdsdebug("sock %p state_change to %d\n", tc->t_sock, sk->sk_state); 56 57 switch (sk->sk_state) { 58 /* ignore connecting sockets as they make progress */ 59 case TCP_SYN_SENT: 60 case TCP_SYN_RECV: 61 break; 62 case TCP_ESTABLISHED: 63 /* Force the peer to reconnect so that we have the 64 * TCP ports going from <smaller-ip>.<transient> to 65 * <larger-ip>.<RDS_TCP_PORT>. We avoid marking the 66 * RDS connection as RDS_CONN_UP until the reconnect, 67 * to avoid RDS datagram loss. 68 */ 69 if (!IS_CANONICAL(cp->cp_conn->c_laddr, cp->cp_conn->c_faddr) && 70 rds_conn_path_transition(cp, RDS_CONN_CONNECTING, 71 RDS_CONN_ERROR)) { 72 rds_conn_path_drop(cp, false); 73 } else { 74 rds_connect_path_complete(cp, RDS_CONN_CONNECTING); 75 } 76 break; 77 case TCP_CLOSE_WAIT: 78 case TCP_CLOSE: 79 rds_conn_path_drop(cp, false); 80 default: 81 break; 82 } 83 out: 84 read_unlock_bh(&sk->sk_callback_lock); 85 state_change(sk); 86 } 87 88 int rds_tcp_conn_path_connect(struct rds_conn_path *cp) 89 { 90 struct socket *sock = NULL; 91 struct sockaddr_in src, dest; 92 int ret; 93 struct rds_connection *conn = cp->cp_conn; 94 struct rds_tcp_connection *tc = cp->cp_transport_data; 95 96 /* for multipath rds,we only trigger the connection after 97 * the handshake probe has determined the number of paths. 98 */ 99 if (cp->cp_index > 0 && cp->cp_conn->c_npaths < 2) 100 return -EAGAIN; 101 102 mutex_lock(&tc->t_conn_path_lock); 103 104 if (rds_conn_path_up(cp)) { 105 mutex_unlock(&tc->t_conn_path_lock); 106 return 0; 107 } 108 ret = sock_create_kern(rds_conn_net(conn), PF_INET, 109 SOCK_STREAM, IPPROTO_TCP, &sock); 110 if (ret < 0) 111 goto out; 112 113 rds_tcp_tune(sock); 114 115 src.sin_family = AF_INET; 116 src.sin_addr.s_addr = (__force u32)conn->c_laddr; 117 src.sin_port = (__force u16)htons(0); 118 119 ret = sock->ops->bind(sock, (struct sockaddr *)&src, sizeof(src)); 120 if (ret) { 121 rdsdebug("bind failed with %d at address %pI4\n", 122 ret, &conn->c_laddr); 123 goto out; 124 } 125 126 dest.sin_family = AF_INET; 127 dest.sin_addr.s_addr = (__force u32)conn->c_faddr; 128 dest.sin_port = (__force u16)htons(RDS_TCP_PORT); 129 130 /* 131 * once we call connect() we can start getting callbacks and they 132 * own the socket 133 */ 134 rds_tcp_set_callbacks(sock, cp); 135 ret = sock->ops->connect(sock, (struct sockaddr *)&dest, sizeof(dest), 136 O_NONBLOCK); 137 138 rdsdebug("connect to address %pI4 returned %d\n", &conn->c_faddr, ret); 139 if (ret == -EINPROGRESS) 140 ret = 0; 141 if (ret == 0) { 142 rds_tcp_keepalive(sock); 143 sock = NULL; 144 } else { 145 rds_tcp_restore_callbacks(sock, cp->cp_transport_data); 146 } 147 148 out: 149 mutex_unlock(&tc->t_conn_path_lock); 150 if (sock) 151 sock_release(sock); 152 return ret; 153 } 154 155 /* 156 * Before killing the tcp socket this needs to serialize with callbacks. The 157 * caller has already grabbed the sending sem so we're serialized with other 158 * senders. 159 * 160 * TCP calls the callbacks with the sock lock so we hold it while we reset the 161 * callbacks to those set by TCP. Our callbacks won't execute again once we 162 * hold the sock lock. 163 */ 164 void rds_tcp_conn_path_shutdown(struct rds_conn_path *cp) 165 { 166 struct rds_tcp_connection *tc = cp->cp_transport_data; 167 struct socket *sock = tc->t_sock; 168 169 rdsdebug("shutting down conn %p tc %p sock %p\n", 170 cp->cp_conn, tc, sock); 171 172 if (sock) { 173 if (rds_destroy_pending(cp->cp_conn)) 174 rds_tcp_set_linger(sock); 175 sock->ops->shutdown(sock, RCV_SHUTDOWN | SEND_SHUTDOWN); 176 lock_sock(sock->sk); 177 rds_tcp_restore_callbacks(sock, tc); /* tc->tc_sock = NULL */ 178 179 release_sock(sock->sk); 180 sock_release(sock); 181 } 182 183 if (tc->t_tinc) { 184 rds_inc_put(&tc->t_tinc->ti_inc); 185 tc->t_tinc = NULL; 186 } 187 tc->t_tinc_hdr_rem = sizeof(struct rds_header); 188 tc->t_tinc_data_rem = 0; 189 } 190