aboutsummaryrefslogtreecommitdiffstats
path: root/net/rds/tcp_connect.c
blob: f9f564a6c960e47b3c243d11a3e11317c5a56353 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
/*
 * Copyright (c) 2006 Oracle.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */
#include <linux/kernel.h>
#include <linux/in.h>
#include <net/tcp.h>

#include "rds.h"
#include "tcp.h"

void rds_tcp_state_change(struct sock *sk)
{
	void (*state_change)(struct sock *sk);
	struct rds_connection *conn;
	struct rds_tcp_connection *tc;

	read_lock(&sk->sk_callback_lock);
	conn = sk->sk_user_data;
	if (!conn) {
		state_change = sk->sk_state_change;
		goto out;
	}
	tc = conn->c_transport_data;
	state_change = tc->t_orig_state_change;

	rdsdebug("sock %p state_change to %d\n", tc->t_sock, sk->sk_state);

	switch(sk->sk_state) {
		/* ignore connecting sockets as they make progress */
		case TCP_SYN_SENT:
		case TCP_SYN_RECV:
			break;
		case TCP_ESTABLISHED:
			rds_connect_complete(conn);
			break;
		case TCP_CLOSE:
			rds_conn_drop(conn);
		default:
			break;
	}
out:
	read_unlock(&sk->sk_callback_lock);
	state_change(sk);
}

int rds_tcp_conn_connect(struct rds_connection *conn)
{
	struct socket *sock = NULL;
	struct sockaddr_in src, dest;
	int ret;

	ret = sock_create(PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
	if (ret < 0)
		goto out;

	rds_tcp_tune(sock);

	src.sin_family = AF_INET;
	src.sin_addr.s_addr = (__force u32)conn->c_laddr;
	src.sin_port = (__force u16)htons(0);

	ret = sock->ops->bind(sock, (struct sockaddr *)&src, sizeof(src));
	if (ret) {
		rdsdebug("bind failed with %d at address %pI4\n",
			 ret, &conn->c_laddr);
		goto out;
	}

	dest.sin_family = AF_INET;
	dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
	dest.sin_port = (__force u16)htons(RDS_TCP_PORT);

	/*
	 * once we call connect() we can start getting callbacks and they
	 * own the socket
	 */
	rds_tcp_set_callbacks(sock, conn);
	ret = sock->ops->connect(sock, (struct sockaddr *)&dest, sizeof(dest),
				 O_NONBLOCK);

	rdsdebug("connect to address %pI4 returned %d\n", &conn->c_faddr, ret);
	if (ret == -EINPROGRESS)
		ret = 0;
	if (ret == 0)
		sock = NULL;
	else
		rds_tcp_restore_callbacks(sock, conn->c_transport_data);

out:
	if (sock)
		sock_release(sock);
	return ret;
}

/*
 * Before killing the tcp socket this needs to serialize with callbacks.  The
 * caller has already grabbed the sending sem so we're serialized with other
 * senders.
 *
 * TCP calls the callbacks with the sock lock so we hold it while we reset the
 * callbacks to those set by TCP.  Our callbacks won't execute again once we
 * hold the sock lock.
 */
void rds_tcp_conn_shutdown(struct rds_connection *conn)
{
	struct rds_tcp_connection *tc = conn->c_transport_data;
	struct socket *sock = tc->t_sock;

	rdsdebug("shutting down conn %p tc %p sock %p\n", conn, tc, sock);

	if (sock) {
		sock->ops->shutdown(sock, RCV_SHUTDOWN | SEND_SHUTDOWN);
		lock_sock(sock->sk);
		rds_tcp_restore_callbacks(sock, tc); /* tc->tc_sock = NULL */

		release_sock(sock->sk);
		sock_release(sock);
	}

	if (tc->t_tinc) {
		rds_inc_put(&tc->t_tinc->ti_inc);
		tc->t_tinc = NULL;
	}
	tc->t_tinc_hdr_rem = sizeof(struct rds_header);
	tc->t_tinc_data_rem = 0;
}