USB: serial: add special case for processing of empty read urbs
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / rds / tcp_connect.c
blob056256285987dea30ffcb2a93b71bf5af8b904c1
1 /*
2 * Copyright (c) 2006 Oracle. All rights reserved.
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:
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
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.
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.
33 #include <linux/kernel.h>
34 #include <linux/in.h>
35 #include <net/tcp.h>
37 #include "rds.h"
38 #include "tcp.h"
40 void rds_tcp_state_change(struct sock *sk)
42 void (*state_change)(struct sock *sk);
43 struct rds_connection *conn;
44 struct rds_tcp_connection *tc;
46 read_lock(&sk->sk_callback_lock);
47 conn = sk->sk_user_data;
48 if (conn == NULL) {
49 state_change = sk->sk_state_change;
50 goto out;
52 tc = conn->c_transport_data;
53 state_change = tc->t_orig_state_change;
55 rdsdebug("sock %p state_change to %d\n", tc->t_sock, sk->sk_state);
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 rds_connect_complete(conn);
64 break;
65 case TCP_CLOSE:
66 rds_conn_drop(conn);
67 default:
68 break;
70 out:
71 read_unlock(&sk->sk_callback_lock);
72 state_change(sk);
75 int rds_tcp_conn_connect(struct rds_connection *conn)
77 struct socket *sock = NULL;
78 struct sockaddr_in src, dest;
79 int ret;
81 ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
82 if (ret < 0)
83 goto out;
85 rds_tcp_tune(sock);
87 src.sin_family = AF_INET;
88 src.sin_addr.s_addr = (__force u32)conn->c_laddr;
89 src.sin_port = (__force u16)htons(0);
91 ret = sock->ops->bind(sock, (struct sockaddr *)&src, sizeof(src));
92 if (ret) {
93 rdsdebug("bind failed with %d at address %pI4\n",
94 ret, &conn->c_laddr);
95 goto out;
98 dest.sin_family = AF_INET;
99 dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
100 dest.sin_port = (__force u16)htons(RDS_TCP_PORT);
103 * once we call connect() we can start getting callbacks and they
104 * own the socket
106 rds_tcp_set_callbacks(sock, conn);
107 ret = sock->ops->connect(sock, (struct sockaddr *)&dest, sizeof(dest),
108 O_NONBLOCK);
109 sock = NULL;
111 rdsdebug("connect to address %pI4 returned %d\n", &conn->c_faddr, ret);
112 if (ret == -EINPROGRESS)
113 ret = 0;
115 out:
116 if (sock)
117 sock_release(sock);
118 return ret;
122 * Before killing the tcp socket this needs to serialize with callbacks. The
123 * caller has already grabbed the sending sem so we're serialized with other
124 * senders.
126 * TCP calls the callbacks with the sock lock so we hold it while we reset the
127 * callbacks to those set by TCP. Our callbacks won't execute again once we
128 * hold the sock lock.
130 void rds_tcp_conn_shutdown(struct rds_connection *conn)
132 struct rds_tcp_connection *tc = conn->c_transport_data;
133 struct socket *sock = tc->t_sock;
135 rdsdebug("shutting down conn %p tc %p sock %p\n", conn, tc, sock);
137 if (sock) {
138 sock->ops->shutdown(sock, RCV_SHUTDOWN | SEND_SHUTDOWN);
139 lock_sock(sock->sk);
140 rds_tcp_restore_callbacks(sock, tc); /* tc->tc_sock = NULL */
142 release_sock(sock->sk);
143 sock_release(sock);
146 if (tc->t_tinc) {
147 rds_inc_put(&tc->t_tinc->ti_inc);
148 tc->t_tinc = NULL;
150 tc->t_tinc_hdr_rem = sizeof(struct rds_header);
151 tc->t_tinc_data_rem = 0;