summaryrefslogtreecommitdiffstats
path: root/net/rds/rdma_transport.c
blob: b15cf316b23a221d47eaf0e7c38200840cc2442b (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
320
321
322
/*
 * Copyright (c) 2009, 2018 Oracle and/or its affiliates. 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/module.h>
#include <rdma/rdma_cm.h>

#include "rds_single_path.h"
#include "rdma_transport.h"
#include "ib.h"

/* Global IPv4 and IPv6 RDS RDMA listener cm_id */
static struct rdma_cm_id *rds_rdma_listen_id;
#if IS_ENABLED(CONFIG_IPV6)
static struct rdma_cm_id *rds6_rdma_listen_id;
#endif

/* Per IB specification 7.7.3, service level is a 4-bit field. */
#define TOS_TO_SL(tos)		((tos) & 0xF)

static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id,
					 struct rdma_cm_event *event,
					 bool isv6)
{
	/* this can be null in the listening path */
	struct rds_connection *conn = cm_id->context;
	struct rds_transport *trans;
	int ret = 0;
	int *err;
	u8 len;

	rdsdebug("conn %p id %p handling event %u (%s)\n", conn, cm_id,
		 event->event, rdma_event_msg(event->event));

	if (cm_id->device->node_type == RDMA_NODE_IB_CA)
		trans = &rds_ib_transport;

	/* Prevent shutdown from tearing down the connection
	 * while we're executing. */
	if (conn) {
		mutex_lock(&conn->c_cm_lock);

		/* If the connection is being shut down, bail out
		 * right away. We return 0 so cm_id doesn't get
		 * destroyed prematurely */
		if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
			/* Reject incoming connections while we're tearing
			 * down an existing one. */
			if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
				ret = 1;
			goto out;
		}
	}

	switch (event->event) {
	case RDMA_CM_EVENT_CONNECT_REQUEST:
		ret = trans->cm_handle_connect(cm_id, event, isv6);
		break;

	case RDMA_CM_EVENT_ADDR_RESOLVED:
		if (conn) {
			rdma_set_service_type(cm_id, conn->c_tos);
			rdma_set_min_rnr_timer(cm_id, IB_RNR_TIMER_000_32);
			/* XXX do we need to clean up if this fails? */
			ret = rdma_resolve_route(cm_id,
						 RDS_RDMA_RESOLVE_TIMEOUT_MS);
		}
		break;

	case RDMA_CM_EVENT_ROUTE_RESOLVED:
		/* Connection could have been dropped so make sure the
		 * cm_id is valid before proceeding
		 */
		if (conn) {
			struct rds_ib_connection *ibic;

			ibic = conn->c_transport_data;
			if (ibic && ibic->i_cm_id == cm_id) {
				cm_id->route.path_rec[0].sl =
					TOS_TO_SL(conn->c_tos);
				ret = trans->cm_initiate_connect(cm_id, isv6);
			} else {
				rds_conn_drop(conn);
			}
		}
		break;

	case RDMA_CM_EVENT_ESTABLISHED:
		if (conn)
			trans->cm_connect_complete(conn, event);
		break;

	case RDMA_CM_EVENT_REJECTED:
		if (!conn)
			break;
		err = (int *)rdma_consumer_reject_data(cm_id, event, &len);
		if (!err ||
		    (err && len >= sizeof(*err) &&
		     ((*err) <= RDS_RDMA_REJ_INCOMPAT))) {
			pr_warn("RDS/RDMA: conn <%pI6c, %pI6c> rejected, dropping connection\n",
				&conn->c_laddr, &conn->c_faddr);

			if (!conn->c_tos)
				conn->c_proposed_version = RDS_PROTOCOL_COMPAT_VERSION;

			rds_conn_drop(conn);
		}
		rdsdebug("Connection rejected: %s\n",
			 rdma_reject_msg(cm_id, event->status));
		break;
	case RDMA_CM_EVENT_ADDR_ERROR:
	case RDMA_CM_EVENT_ROUTE_ERROR:
	case RDMA_CM_EVENT_CONNECT_ERROR:
	case RDMA_CM_EVENT_UNREACHABLE:
	case RDMA_CM_EVENT_DEVICE_REMOVAL:
	case RDMA_CM_EVENT_ADDR_CHANGE:
		if (conn)
			rds_conn_drop(conn);
		break;

	case RDMA_CM_EVENT_DISCONNECTED:
		if (!conn)
			break;
		rdsdebug("DISCONNECT event - dropping connection "
			 "%pI6c->%pI6c\n", &conn->c_laddr,
			 &conn->c_faddr);
		rds_conn_drop(conn);
		break;

	case RDMA_CM_EVENT_TIMEWAIT_EXIT:
		if (conn) {
			pr_info("RDS: RDMA_CM_EVENT_TIMEWAIT_EXIT event: dropping connection %pI6c->%pI6c\n",
				&conn->c_laddr, &conn->c_faddr);
			rds_conn_drop(conn);
		}
		break;

	default:
		/* things like device disconnect? */
		printk(KERN_ERR "RDS: unknown event %u (%s)!\n",
		       event->event, rdma_event_msg(event->event));
		break;
	}

out:
	if (conn)
		mutex_unlock(&conn->c_cm_lock);

	rdsdebug("id %p event %u (%s) handling ret %d\n", cm_id, event->event,
		 rdma_event_msg(event->event), ret);

	return ret;
}

int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
			      struct rdma_cm_event *event)
{
	return rds_rdma_cm_event_handler_cmn(cm_id, event, false);
}

#if IS_ENABLED(CONFIG_IPV6)
int rds6_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
			       struct rdma_cm_event *event)
{
	return rds_rdma_cm_event_handler_cmn(cm_id, event, true);
}
#endif

static int rds_rdma_listen_init_common(rdma_cm_event_handler handler,
				       struct sockaddr *sa,
				       struct rdma_cm_id **ret_cm_id)
{
	struct rdma_cm_id *cm_id;
	int ret;

	cm_id = rdma_create_id(&init_net, handler, NULL,
			       RDMA_PS_TCP, IB_QPT_RC);
	if (IS_ERR(cm_id)) {
		ret = PTR_ERR(cm_id);
		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
		       "rdma_create_id() returned %d\n", ret);
		return ret;
	}

	/*
	 * XXX I bet this binds the cm_id to a device.  If we want to support
	 * fail-over we'll have to take this into consideration.
	 */
	ret = rdma_bind_addr(cm_id, sa);
	if (ret) {
		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
		       "rdma_bind_addr() returned %d\n", ret);
		goto out;
	}

	ret = rdma_listen(cm_id, 128);
	if (ret) {
		printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
		       "rdma_listen() returned %d\n", ret);
		goto out;
	}

	rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);

	*ret_cm_id = cm_id;
	cm_id = NULL;
out:
	if (cm_id)
		rdma_destroy_id(cm_id);
	return ret;
}

/* Initialize the RDS RDMA listeners.  We create two listeners for
 * compatibility reason.  The one on RDS_PORT is used for IPv4
 * requests only.  The one on RDS_CM_PORT is used for IPv6 requests
 * only.  So only IPv6 enabled RDS module will communicate using this
 * port.
 */
static int rds_rdma_listen_init(void)
{
	int ret;
#if IS_ENABLED(CONFIG_IPV6)
	struct sockaddr_in6 sin6;
#endif
	struct sockaddr_in sin;

	sin.sin_family = PF_INET;
	sin.sin_addr.s_addr = htonl(INADDR_ANY);
	sin.sin_port = htons(RDS_PORT);
	ret = rds_rdma_listen_init_common(rds_rdma_cm_event_handler,
					  (struct sockaddr *)&sin,
					  &rds_rdma_listen_id);
	if (ret != 0)
		return ret;

#if IS_ENABLED(CONFIG_IPV6)
	sin6.sin6_family = PF_INET6;
	sin6.sin6_addr = in6addr_any;
	sin6.sin6_port = htons(RDS_CM_PORT);
	sin6.sin6_scope_id = 0;
	sin6.sin6_flowinfo = 0;
	ret = rds_rdma_listen_init_common(rds6_rdma_cm_event_handler,
					  (struct sockaddr *)&sin6,
					  &rds6_rdma_listen_id);
	/* Keep going even when IPv6 is not enabled in the system. */
	if (ret != 0)
		rdsdebug("Cannot set up IPv6 RDMA listener\n");
#endif
	return 0;
}

static void rds_rdma_listen_stop(void)
{
	if (rds_rdma_listen_id) {
		rdsdebug("cm %p\n", rds_rdma_listen_id);
		rdma_destroy_id(rds_rdma_listen_id);
		rds_rdma_listen_id = NULL;
	}
#if IS_ENABLED(CONFIG_IPV6)
	if (rds6_rdma_listen_id) {
		rdsdebug("cm %p\n", rds6_rdma_listen_id);
		rdma_destroy_id(rds6_rdma_listen_id);
		rds6_rdma_listen_id = NULL;
	}
#endif
}

static int __init rds_rdma_init(void)
{
	int ret;

	ret = rds_ib_init();
	if (ret)
		goto out;

	ret = rds_rdma_listen_init();
	if (ret)
		rds_ib_exit();
out:
	return ret;
}
module_init(rds_rdma_init);

static void __exit rds_rdma_exit(void)
{
	/* stop listening first to ensure no new connections are attempted */
	rds_rdma_listen_stop();
	rds_ib_exit();
}
module_exit(rds_rdma_exit);

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