summaryrefslogtreecommitdiff
path: root/net/rds/tcp.c
blob: e0ac9009db1af26891d6e836d99bdd1999f7f969 (plain)
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
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
/*
 * 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"

/* only for info exporting */
static DEFINE_SPINLOCK(rds_tcp_tc_list_lock);
static LIST_HEAD(rds_tcp_tc_list);
unsigned int rds_tcp_tc_count;

/* Track rds_tcp_connection structs so they can be cleaned up */
static DEFINE_SPINLOCK(rds_tcp_conn_lock);
static LIST_HEAD(rds_tcp_conn_list);

static struct kmem_cache *rds_tcp_conn_slab;

#define RDS_TCP_DEFAULT_BUFSIZE (128 * 1024)

/* doing it this way avoids calling tcp_sk() */
void rds_tcp_nonagle(struct socket *sock)
{
	mm_segment_t oldfs = get_fs();
	int val = 1;

	set_fs(KERNEL_DS);
	sock->ops->setsockopt(sock, SOL_TCP, TCP_NODELAY, (char __user *)&val,
			      sizeof(val));
	set_fs(oldfs);
}

void rds_tcp_tune(struct socket *sock)
{
	struct sock *sk = sock->sk;

	rds_tcp_nonagle(sock);

	/*
	 * We're trying to saturate gigabit with the default,
	 * see svc_sock_setbufsize().
	 */
	lock_sock(sk);
	sk->sk_sndbuf = RDS_TCP_DEFAULT_BUFSIZE;
	sk->sk_rcvbuf = RDS_TCP_DEFAULT_BUFSIZE;
	sk->sk_userlocks |= SOCK_SNDBUF_LOCK|SOCK_RCVBUF_LOCK;
	release_sock(sk);
}

u32 rds_tcp_snd_nxt(struct rds_tcp_connection *tc)
{
	return tcp_sk(tc->t_sock->sk)->snd_nxt;
}

u32 rds_tcp_snd_una(struct rds_tcp_connection *tc)
{
	return tcp_sk(tc->t_sock->sk)->snd_una;
}

void rds_tcp_restore_callbacks(struct socket *sock,
			       struct rds_tcp_connection *tc)
{
	rdsdebug("restoring sock %p callbacks from tc %p\n", sock, tc);
	write_lock_bh(&sock->sk->sk_callback_lock);

	/* done under the callback_lock to serialize with write_space */
	spin_lock(&rds_tcp_tc_list_lock);
	list_del_init(&tc->t_list_item);
	rds_tcp_tc_count--;
	spin_unlock(&rds_tcp_tc_list_lock);

	tc->t_sock = NULL;

	sock->sk->sk_write_space = tc->t_orig_write_space;
	sock->sk->sk_data_ready = tc->t_orig_data_ready;
	sock->sk->sk_state_change = tc->t_orig_state_change;
	sock->sk->sk_user_data = NULL;

	write_unlock_bh(&sock->sk->sk_callback_lock);
}

/*
 * This is the only path that sets tc->t_sock.  Send and receive trust that
 * it is set.  The RDS_CONN_CONNECTED bit protects those paths from being
 * called while it isn't set.
 */
void rds_tcp_set_callbacks(struct socket *sock, struct rds_connection *conn)
{
	struct rds_tcp_connection *tc = conn->c_transport_data;

	rdsdebug("setting sock %p callbacks to tc %p\n", sock, tc);
	write_lock_bh(&sock->sk->sk_callback_lock);

	/* done under the callback_lock to serialize with write_space */
	spin_lock(&rds_tcp_tc_list_lock);
	list_add_tail(&tc->t_list_item, &rds_tcp_tc_list);
	rds_tcp_tc_count++;
	spin_unlock(&rds_tcp_tc_list_lock);

	/* accepted sockets need our listen data ready undone */
	if (sock->sk->sk_data_ready == rds_tcp_listen_data_ready)
		sock->sk->sk_data_ready = sock->sk->sk_user_data;

	tc->t_sock = sock;
	tc->conn = conn;
	tc->t_orig_data_ready = sock->sk->sk_data_ready;
	tc->t_orig_write_space = sock->sk->sk_write_space;
	tc->t_orig_state_change = sock->sk->sk_state_change;

	sock->sk->sk_user_data = conn;
	sock->sk->sk_data_ready = rds_tcp_data_ready;
	sock->sk->sk_write_space = rds_tcp_write_space;
	sock->sk->sk_state_change = rds_tcp_state_change;

	write_unlock_bh(&sock->sk->sk_callback_lock);
}

static void rds_tcp_tc_info(struct socket *sock, unsigned int len,
			    struct rds_info_iterator *iter,
			    struct rds_info_lengths *lens)
{
	struct rds_info_tcp_socket tsinfo;
	struct rds_tcp_connection *tc;
	unsigned long flags;
	struct sockaddr_in sin;
	int sinlen;

	spin_lock_irqsave(&rds_tcp_tc_list_lock, flags);

	if (len / sizeof(tsinfo) < rds_tcp_tc_count)
		goto out;

	list_for_each_entry(tc, &rds_tcp_tc_list, t_list_item) {

		sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 0);
		tsinfo.local_addr = sin.sin_addr.s_addr;
		tsinfo.local_port = sin.sin_port;
		sock->ops->getname(sock, (struct sockaddr *)&sin, &sinlen, 1);
		tsinfo.peer_addr = sin.sin_addr.s_addr;
		tsinfo.peer_port = sin.sin_port;

		tsinfo.hdr_rem = tc->t_tinc_hdr_rem;
		tsinfo.data_rem = tc->t_tinc_data_rem;
		tsinfo.last_sent_nxt = tc->t_last_sent_nxt;
		tsinfo.last_expected_una = tc->t_last_expected_una;
		tsinfo.last_seen_una = tc->t_last_seen_una;

		rds_info_copy(iter, &tsinfo, sizeof(tsinfo));
	}

out:
	lens->nr = rds_tcp_tc_count;
	lens->each = sizeof(tsinfo);

	spin_unlock_irqrestore(&rds_tcp_tc_list_lock, flags);
}

static int rds_tcp_laddr_check(__be32 addr)
{
	if (inet_addr_type(&init_net, addr) == RTN_LOCAL)
		return 0;
	return -EADDRNOTAVAIL;
}

static int rds_tcp_conn_alloc(struct rds_connection *conn, gfp_t gfp)
{
	struct rds_tcp_connection *tc;

	tc = kmem_cache_alloc(rds_tcp_conn_slab, gfp);
	if (tc == NULL)
		return -ENOMEM;

	tc->t_sock = NULL;
	tc->t_tinc = NULL;
	tc->t_tinc_hdr_rem = sizeof(struct rds_header);
	tc->t_tinc_data_rem = 0;

	conn->c_transport_data = tc;

	spin_lock_irq(&rds_tcp_conn_lock);
	list_add_tail(&tc->t_tcp_node, &rds_tcp_conn_list);
	spin_unlock_irq(&rds_tcp_conn_lock);

	rdsdebug("alloced tc %p\n", conn->c_transport_data);
	return 0;
}

static void rds_tcp_conn_free(void *arg)
{
	struct rds_tcp_connection *tc = arg;
	rdsdebug("freeing tc %p\n", tc);
	kmem_cache_free(rds_tcp_conn_slab, tc);
}

static void rds_tcp_destroy_conns(void)
{
	struct rds_tcp_connection *tc, *_tc;
	LIST_HEAD(tmp_list);

	/* avoid calling conn_destroy with irqs off */
	spin_lock_irq(&rds_tcp_conn_lock);
	list_splice(&rds_tcp_conn_list, &tmp_list);
	INIT_LIST_HEAD(&rds_tcp_conn_list);
	spin_unlock_irq(&rds_tcp_conn_lock);

	list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) {
		if (tc->conn->c_passive)
			rds_conn_destroy(tc->conn->c_passive);
		rds_conn_destroy(tc->conn);
	}
}

void rds_tcp_exit(void)
{
	rds_info_deregister_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);
	rds_tcp_listen_stop();
	rds_tcp_destroy_conns();
	rds_trans_unregister(&rds_tcp_transport);
	rds_tcp_recv_exit();
	kmem_cache_destroy(rds_tcp_conn_slab);
}
module_exit(rds_tcp_exit);

struct rds_transport rds_tcp_transport = {
	.laddr_check		= rds_tcp_laddr_check,
	.xmit_prepare		= rds_tcp_xmit_prepare,
	.xmit_complete		= rds_tcp_xmit_complete,
	.xmit_cong_map		= rds_tcp_xmit_cong_map,
	.xmit			= rds_tcp_xmit,
	.recv			= rds_tcp_recv,
	.conn_alloc		= rds_tcp_conn_alloc,
	.conn_free		= rds_tcp_conn_free,
	.conn_connect		= rds_tcp_conn_connect,
	.conn_shutdown		= rds_tcp_conn_shutdown,
	.inc_copy_to_user	= rds_tcp_inc_copy_to_user,
	.inc_purge		= rds_tcp_inc_purge,
	.inc_free		= rds_tcp_inc_free,
	.stats_info_copy	= rds_tcp_stats_info_copy,
	.exit			= rds_tcp_exit,
	.t_owner		= THIS_MODULE,
	.t_name			= "tcp",
	.t_prefer_loopback	= 1,
};

int __init rds_tcp_init(void)
{
	int ret;

	rds_tcp_conn_slab = kmem_cache_create("rds_tcp_connection",
					      sizeof(struct rds_tcp_connection),
					      0, 0, NULL);
	if (rds_tcp_conn_slab == NULL) {
		ret = -ENOMEM;
		goto out;
	}

	ret = rds_tcp_recv_init();
	if (ret)
		goto out_slab;

	ret = rds_trans_register(&rds_tcp_transport);
	if (ret)
		goto out_recv;

	ret = rds_tcp_listen_init();
	if (ret)
		goto out_register;

	rds_info_register_func(RDS_INFO_TCP_SOCKETS, rds_tcp_tc_info);

	goto out;

out_register:
	rds_trans_unregister(&rds_tcp_transport);
out_recv:
	rds_tcp_recv_exit();
out_slab:
	kmem_cache_destroy(rds_tcp_conn_slab);
out:
	return ret;
}
module_init(rds_tcp_init);

MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
MODULE_DESCRIPTION("RDS: TCP transport");
MODULE_LICENSE("Dual BSD/GPL");