1 /* 2 * Copyright (c) 2006, 2017 Oracle and/or its affiliates. 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 (rds_addr_cmp(&cp->cp_conn->c_laddr, 70 &cp->cp_conn->c_faddr) >= 0 && 71 rds_conn_path_transition(cp, RDS_CONN_CONNECTING, 72 RDS_CONN_ERROR)) { 73 rds_conn_path_drop(cp, false); 74 } else { 75 rds_connect_path_complete(cp, RDS_CONN_CONNECTING); 76 } 77 break; 78 case TCP_CLOSE_WAIT: 79 case TCP_CLOSE: 80 rds_conn_path_drop(cp, false); 81 break; 82 default: 83 break; 84 } 85 out: 86 read_unlock_bh(&sk->sk_callback_lock); 87 state_change(sk); 88 } 89 90 int rds_tcp_conn_path_connect(struct rds_conn_path *cp) 91 { 92 struct socket *sock = NULL; 93 struct sockaddr_in6 sin6; 94 struct sockaddr_in sin; 95 struct sockaddr *addr; 96 int addrlen; 97 bool isv6; 98 int ret; 99 struct rds_connection *conn = cp->cp_conn; 100 struct rds_tcp_connection *tc = cp->cp_transport_data; 101 102 /* for multipath rds,we only trigger the connection after 103 * the handshake probe has determined the number of paths. 104 */ 105 if (cp->cp_index > 0 && cp->cp_conn->c_npaths < 2) 106 return -EAGAIN; 107 108 mutex_lock(&tc->t_conn_path_lock); 109 110 if (rds_conn_path_up(cp)) { 111 mutex_unlock(&tc->t_conn_path_lock); 112 return 0; 113 } 114 if (ipv6_addr_v4mapped(&conn->c_laddr)) { 115 ret = sock_create_kern(rds_conn_net(conn), PF_INET, 116 SOCK_STREAM, IPPROTO_TCP, &sock); 117 isv6 = false; 118 } else { 119 ret = sock_create_kern(rds_conn_net(conn), PF_INET6, 120 SOCK_STREAM, IPPROTO_TCP, &sock); 121 isv6 = true; 122 } 123 124 if (ret < 0) 125 goto out; 126 127 rds_tcp_tune(sock); 128 129 if (isv6) { 130 sin6.sin6_family = AF_INET6; 131 sin6.sin6_addr = conn->c_laddr; 132 sin6.sin6_port = 0; 133 sin6.sin6_flowinfo = 0; 134 sin6.sin6_scope_id = conn->c_dev_if; 135 addr = (struct sockaddr *)&sin6; 136 addrlen = sizeof(sin6); 137 } else { 138 sin.sin_family = AF_INET; 139 sin.sin_addr.s_addr = conn->c_laddr.s6_addr32[3]; 140 sin.sin_port = 0; 141 addr = (struct sockaddr *)&sin; 142 addrlen = sizeof(sin); 143 } 144 145 ret = sock->ops->bind(sock, addr, addrlen); 146 if (ret) { 147 rdsdebug("bind failed with %d at address %pI6c\n", 148 ret, &conn->c_laddr); 149 goto out; 150 } 151 152 if (isv6) { 153 sin6.sin6_family = AF_INET6; 154 sin6.sin6_addr = conn->c_faddr; 155 sin6.sin6_port = htons(RDS_TCP_PORT); 156 sin6.sin6_flowinfo = 0; 157 sin6.sin6_scope_id = conn->c_dev_if; 158 addr = (struct sockaddr *)&sin6; 159 addrlen = sizeof(sin6); 160 } else { 161 sin.sin_family = AF_INET; 162 sin.sin_addr.s_addr = conn->c_faddr.s6_addr32[3]; 163 sin.sin_port = htons(RDS_TCP_PORT); 164 addr = (struct sockaddr *)&sin; 165 addrlen = sizeof(sin); 166 } 167 168 /* 169 * once we call connect() we can start getting callbacks and they 170 * own the socket 171 */ 172 rds_tcp_set_callbacks(sock, cp); 173 ret = sock->ops->connect(sock, addr, addrlen, O_NONBLOCK); 174 175 rdsdebug("connect to address %pI6c returned %d\n", &conn->c_faddr, ret); 176 if (ret == -EINPROGRESS) 177 ret = 0; 178 if (ret == 0) { 179 rds_tcp_keepalive(sock); 180 sock = NULL; 181 } else { 182 rds_tcp_restore_callbacks(sock, cp->cp_transport_data); 183 } 184 185 out: 186 mutex_unlock(&tc->t_conn_path_lock); 187 if (sock) 188 sock_release(sock); 189 return ret; 190 } 191 192 /* 193 * Before killing the tcp socket this needs to serialize with callbacks. The 194 * caller has already grabbed the sending sem so we're serialized with other 195 * senders. 196 * 197 * TCP calls the callbacks with the sock lock so we hold it while we reset the 198 * callbacks to those set by TCP. Our callbacks won't execute again once we 199 * hold the sock lock. 200 */ 201 void rds_tcp_conn_path_shutdown(struct rds_conn_path *cp) 202 { 203 struct rds_tcp_connection *tc = cp->cp_transport_data; 204 struct socket *sock = tc->t_sock; 205 206 rdsdebug("shutting down conn %p tc %p sock %p\n", 207 cp->cp_conn, tc, sock); 208 209 if (sock) { 210 if (rds_destroy_pending(cp->cp_conn)) 211 sock_no_linger(sock->sk); 212 sock->ops->shutdown(sock, RCV_SHUTDOWN | SEND_SHUTDOWN); 213 lock_sock(sock->sk); 214 rds_tcp_restore_callbacks(sock, tc); /* tc->tc_sock = NULL */ 215 216 release_sock(sock->sk); 217 sock_release(sock); 218 } 219 220 if (tc->t_tinc) { 221 rds_inc_put(&tc->t_tinc->ti_inc); 222 tc->t_tinc = NULL; 223 } 224 tc->t_tinc_hdr_rem = sizeof(struct rds_header); 225 tc->t_tinc_data_rem = 0; 226 } 227