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 40void 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 default: 82 break; 83 } 84out: 85 read_unlock_bh(&sk->sk_callback_lock); 86 state_change(sk); 87} 88 89int rds_tcp_conn_path_connect(struct rds_conn_path *cp) 90{ 91 struct socket *sock = NULL; 92 struct sockaddr_in6 sin6; 93 struct sockaddr_in sin; 94 struct sockaddr *addr; 95 int addrlen; 96 bool isv6; 97 int ret; 98 struct rds_connection *conn = cp->cp_conn; 99 struct rds_tcp_connection *tc = cp->cp_transport_data; 100 101 /* for multipath rds,we only trigger the connection after 102 * the handshake probe has determined the number of paths. 103 */ 104 if (cp->cp_index > 0 && cp->cp_conn->c_npaths < 2) 105 return -EAGAIN; 106 107 mutex_lock(&tc->t_conn_path_lock); 108 109 if (rds_conn_path_up(cp)) { 110 mutex_unlock(&tc->t_conn_path_lock); 111 return 0; 112 } 113 if (ipv6_addr_v4mapped(&conn->c_laddr)) { 114 ret = sock_create_kern(rds_conn_net(conn), PF_INET, 115 SOCK_STREAM, IPPROTO_TCP, &sock); 116 isv6 = false; 117 } else { 118 ret = sock_create_kern(rds_conn_net(conn), PF_INET6, 119 SOCK_STREAM, IPPROTO_TCP, &sock); 120 isv6 = true; 121 } 122 123 if (ret < 0) 124 goto out; 125 126 rds_tcp_tune(sock); 127 128 if (isv6) { 129 sin6.sin6_family = AF_INET6; 130 sin6.sin6_addr = conn->c_laddr; 131 sin6.sin6_port = 0; 132 sin6.sin6_flowinfo = 0; 133 sin6.sin6_scope_id = conn->c_dev_if; 134 addr = (struct sockaddr *)&sin6; 135 addrlen = sizeof(sin6); 136 } else { 137 sin.sin_family = AF_INET; 138 sin.sin_addr.s_addr = conn->c_laddr.s6_addr32[3]; 139 sin.sin_port = 0; 140 addr = (struct sockaddr *)&sin; 141 addrlen = sizeof(sin); 142 } 143 144 ret = kernel_bind(sock, addr, addrlen); 145 if (ret) { 146 rdsdebug("bind failed with %d at address %pI6c\n", 147 ret, &conn->c_laddr); 148 goto out; 149 } 150 151 if (isv6) { 152 sin6.sin6_family = AF_INET6; 153 sin6.sin6_addr = conn->c_faddr; 154 sin6.sin6_port = htons(RDS_TCP_PORT); 155 sin6.sin6_flowinfo = 0; 156 sin6.sin6_scope_id = conn->c_dev_if; 157 addr = (struct sockaddr *)&sin6; 158 addrlen = sizeof(sin6); 159 } else { 160 sin.sin_family = AF_INET; 161 sin.sin_addr.s_addr = conn->c_faddr.s6_addr32[3]; 162 sin.sin_port = htons(RDS_TCP_PORT); 163 addr = (struct sockaddr *)&sin; 164 addrlen = sizeof(sin); 165 } 166 167 /* 168 * once we call connect() we can start getting callbacks and they 169 * own the socket 170 */ 171 rds_tcp_set_callbacks(sock, cp); 172 ret = kernel_connect(sock, addr, addrlen, O_NONBLOCK); 173 174 rdsdebug("connect to address %pI6c returned %d\n", &conn->c_faddr, ret); 175 if (ret == -EINPROGRESS) 176 ret = 0; 177 if (ret == 0) { 178 rds_tcp_keepalive(sock); 179 sock = NULL; 180 } else { 181 rds_tcp_restore_callbacks(sock, cp->cp_transport_data); 182 } 183 184out: 185 mutex_unlock(&tc->t_conn_path_lock); 186 if (sock) 187 sock_release(sock); 188 return ret; 189} 190 191/* 192 * Before killing the tcp socket this needs to serialize with callbacks. The 193 * caller has already grabbed the sending sem so we're serialized with other 194 * senders. 195 * 196 * TCP calls the callbacks with the sock lock so we hold it while we reset the 197 * callbacks to those set by TCP. Our callbacks won't execute again once we 198 * hold the sock lock. 199 */ 200void rds_tcp_conn_path_shutdown(struct rds_conn_path *cp) 201{ 202 struct rds_tcp_connection *tc = cp->cp_transport_data; 203 struct socket *sock = tc->t_sock; 204 205 rdsdebug("shutting down conn %p tc %p sock %p\n", 206 cp->cp_conn, tc, sock); 207 208 if (sock) { 209 if (rds_destroy_pending(cp->cp_conn)) 210 sock_no_linger(sock->sk); 211 sock->ops->shutdown(sock, RCV_SHUTDOWN | SEND_SHUTDOWN); 212 lock_sock(sock->sk); 213 rds_tcp_restore_callbacks(sock, tc); /* tc->tc_sock = NULL */ 214 215 release_sock(sock->sk); 216 sock_release(sock); 217 } 218 219 if (tc->t_tinc) { 220 rds_inc_put(&tc->t_tinc->ti_inc); 221 tc->t_tinc = NULL; 222 } 223 tc->t_tinc_hdr_rem = sizeof(struct rds_header); 224 tc->t_tinc_data_rem = 0; 225} 226