1 /*
2 * Copyright (c) 2009, 2018 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/module.h>
34 #include <rdma/rdma_cm.h>
35
36 #include "rds_single_path.h"
37 #include "rdma_transport.h"
38 #include "ib.h"
39
40 /* Global IPv4 and IPv6 RDS RDMA listener cm_id */
41 static struct rdma_cm_id *rds_rdma_listen_id;
42 #if IS_ENABLED(CONFIG_IPV6)
43 static struct rdma_cm_id *rds6_rdma_listen_id;
44 #endif
45
46 /* Per IB specification 7.7.3, service level is a 4-bit field. */
47 #define TOS_TO_SL(tos) ((tos) & 0xF)
48
49 static int rds_rdma_cm_event_handler_cmn(struct rdma_cm_id *cm_id,
50 struct rdma_cm_event *event,
51 bool isv6)
52 {
53 /* this can be null in the listening path */
54 struct rds_connection *conn = cm_id->context;
55 struct rds_transport *trans;
56 int ret = 0;
57 int *err;
58 u8 len;
59
60 rdsdebug("conn %p id %p handling event %u (%s)\n", conn, cm_id,
61 event->event, rdma_event_msg(event->event));
62
63 if (cm_id->device->node_type == RDMA_NODE_IB_CA)
64 trans = &rds_ib_transport;
65
66 /* Prevent shutdown from tearing down the connection
67 * while we're executing. */
68 if (conn) {
69 mutex_lock(&conn->c_cm_lock);
70
71 /* If the connection is being shut down, bail out
72 * right away. We return 0 so cm_id doesn't get
73 * destroyed prematurely */
74 if (rds_conn_state(conn) == RDS_CONN_DISCONNECTING) {
75 /* Reject incoming connections while we're tearing
76 * down an existing one. */
77 if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
78 ret = 1;
79 goto out;
80 }
81 }
82
83 switch (event->event) {
84 case RDMA_CM_EVENT_CONNECT_REQUEST:
85 ret = trans->cm_handle_connect(cm_id, event, isv6);
86 break;
87
88 case RDMA_CM_EVENT_ADDR_RESOLVED:
89 if (conn) {
90 rdma_set_service_type(cm_id, conn->c_tos);
91 rdma_set_min_rnr_timer(cm_id, IB_RNR_TIMER_000_32);
92 /* XXX do we need to clean up if this fails? */
93 ret = rdma_resolve_route(cm_id,
94 RDS_RDMA_RESOLVE_TIMEOUT_MS);
95 }
96 break;
97
98 case RDMA_CM_EVENT_ROUTE_RESOLVED:
99 /* Connection could have been dropped so make sure the
100 * cm_id is valid before proceeding
101 */
102 if (conn) {
103 struct rds_ib_connection *ibic;
104
105 ibic = conn->c_transport_data;
106 if (ibic && ibic->i_cm_id == cm_id) {
107 cm_id->route.path_rec[0].sl =
108 TOS_TO_SL(conn->c_tos);
109 ret = trans->cm_initiate_connect(cm_id, isv6);
110 } else {
111 rds_conn_drop(conn);
112 }
113 }
114 break;
115
116 case RDMA_CM_EVENT_ESTABLISHED:
117 if (conn)
118 trans->cm_connect_complete(conn, event);
119 break;
120
121 case RDMA_CM_EVENT_REJECTED:
122 if (!conn)
123 break;
124 err = (int *)rdma_consumer_reject_data(cm_id, event, &len);
125 if (!err ||
126 (err && len >= sizeof(*err) &&
127 ((*err) <= RDS_RDMA_REJ_INCOMPAT))) {
128 pr_warn("RDS/RDMA: conn <%pI6c, %pI6c> rejected, dropping connection\n",
129 &conn->c_laddr, &conn->c_faddr);
130
131 if (!conn->c_tos)
132 conn->c_proposed_version = RDS_PROTOCOL_COMPAT_VERSION;
133
134 rds_conn_drop(conn);
135 }
136 rdsdebug("Connection rejected: %s\n",
137 rdma_reject_msg(cm_id, event->status));
138 break;
139 case RDMA_CM_EVENT_ADDR_ERROR:
140 case RDMA_CM_EVENT_ROUTE_ERROR:
141 case RDMA_CM_EVENT_CONNECT_ERROR:
142 case RDMA_CM_EVENT_UNREACHABLE:
143 case RDMA_CM_EVENT_DEVICE_REMOVAL:
144 case RDMA_CM_EVENT_ADDR_CHANGE:
145 if (conn)
146 rds_conn_drop(conn);
147 break;
148
149 case RDMA_CM_EVENT_DISCONNECTED:
150 if (!conn)
151 break;
152 rdsdebug("DISCONNECT event - dropping connection "
153 "%pI6c->%pI6c\n", &conn->c_laddr,
154 &conn->c_faddr);
155 rds_conn_drop(conn);
156 break;
157
158 case RDMA_CM_EVENT_TIMEWAIT_EXIT:
159 if (conn) {
160 pr_info("RDS: RDMA_CM_EVENT_TIMEWAIT_EXIT event: dropping connection %pI6c->%pI6c\n",
161 &conn->c_laddr, &conn->c_faddr);
162 rds_conn_drop(conn);
163 }
164 break;
165
166 default:
167 /* things like device disconnect? */
168 printk(KERN_ERR "RDS: unknown event %u (%s)!\n",
169 event->event, rdma_event_msg(event->event));
170 break;
171 }
172
173 out:
174 if (conn)
175 mutex_unlock(&conn->c_cm_lock);
176
177 rdsdebug("id %p event %u (%s) handling ret %d\n", cm_id, event->event,
178 rdma_event_msg(event->event), ret);
179
180 return ret;
181 }
182
183 int rds_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
184 struct rdma_cm_event *event)
185 {
186 return rds_rdma_cm_event_handler_cmn(cm_id, event, false);
187 }
188
189 #if IS_ENABLED(CONFIG_IPV6)
190 int rds6_rdma_cm_event_handler(struct rdma_cm_id *cm_id,
191 struct rdma_cm_event *event)
192 {
193 return rds_rdma_cm_event_handler_cmn(cm_id, event, true);
194 }
195 #endif
196
197 static int rds_rdma_listen_init_common(rdma_cm_event_handler handler,
198 struct sockaddr *sa,
199 struct rdma_cm_id **ret_cm_id)
200 {
201 struct rdma_cm_id *cm_id;
202 int ret;
203
204 cm_id = rdma_create_id(&init_net, handler, NULL,
205 RDMA_PS_TCP, IB_QPT_RC);
206 if (IS_ERR(cm_id)) {
207 ret = PTR_ERR(cm_id);
208 printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
209 "rdma_create_id() returned %d\n", ret);
210 return ret;
211 }
212
213 /*
214 * XXX I bet this binds the cm_id to a device. If we want to support
215 * fail-over we'll have to take this into consideration.
216 */
217 ret = rdma_bind_addr(cm_id, sa);
218 if (ret) {
219 printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
220 "rdma_bind_addr() returned %d\n", ret);
221 goto out;
222 }
223
224 ret = rdma_listen(cm_id, 128);
225 if (ret) {
226 printk(KERN_ERR "RDS/RDMA: failed to setup listener, "
227 "rdma_listen() returned %d\n", ret);
228 goto out;
229 }
230
231 rdsdebug("cm %p listening on port %u\n", cm_id, RDS_PORT);
232
233 *ret_cm_id = cm_id;
234 cm_id = NULL;
235 out:
236 if (cm_id)
237 rdma_destroy_id(cm_id);
238 return ret;
239 }
240
241 /* Initialize the RDS RDMA listeners. We create two listeners for
242 * compatibility reason. The one on RDS_PORT is used for IPv4
243 * requests only. The one on RDS_CM_PORT is used for IPv6 requests
244 * only. So only IPv6 enabled RDS module will communicate using this
245 * port.
246 */
247 static int rds_rdma_listen_init(void)
248 {
249 int ret;
250 #if IS_ENABLED(CONFIG_IPV6)
251 struct sockaddr_in6 sin6;
252 #endif
253 struct sockaddr_in sin;
254
255 sin.sin_family = PF_INET;
256 sin.sin_addr.s_addr = htonl(INADDR_ANY);
257 sin.sin_port = htons(RDS_PORT);
258 ret = rds_rdma_listen_init_common(rds_rdma_cm_event_handler,
259 (struct sockaddr *)&sin,
260 &rds_rdma_listen_id);
261 if (ret != 0)
262 return ret;
263
264 #if IS_ENABLED(CONFIG_IPV6)
265 sin6.sin6_family = PF_INET6;
266 sin6.sin6_addr = in6addr_any;
267 sin6.sin6_port = htons(RDS_CM_PORT);
268 sin6.sin6_scope_id = 0;
269 sin6.sin6_flowinfo = 0;
270 ret = rds_rdma_listen_init_common(rds6_rdma_cm_event_handler,
271 (struct sockaddr *)&sin6,
272 &rds6_rdma_listen_id);
273 /* Keep going even when IPv6 is not enabled in the system. */
274 if (ret != 0)
275 rdsdebug("Cannot set up IPv6 RDMA listener\n");
276 #endif
277 return 0;
278 }
279
280 static void rds_rdma_listen_stop(void)
281 {
282 if (rds_rdma_listen_id) {
283 rdsdebug("cm %p\n", rds_rdma_listen_id);
284 rdma_destroy_id(rds_rdma_listen_id);
285 rds_rdma_listen_id = NULL;
286 }
287 #if IS_ENABLED(CONFIG_IPV6)
288 if (rds6_rdma_listen_id) {
289 rdsdebug("cm %p\n", rds6_rdma_listen_id);
290 rdma_destroy_id(rds6_rdma_listen_id);
291 rds6_rdma_listen_id = NULL;
292 }
293 #endif
294 }
295
296 static int __init rds_rdma_init(void)
297 {
298 int ret;
299
300 ret = rds_ib_init();
301 if (ret)
302 goto out;
303
304 ret = rds_rdma_listen_init();
305 if (ret)
306 rds_ib_exit();
307 out:
308 return ret;
309 }
310 module_init(rds_rdma_init);
311
312 static void __exit rds_rdma_exit(void)
313 {
314 /* stop listening first to ensure no new connections are attempted */
315 rds_rdma_listen_stop();
316 rds_ib_exit();
317 }
318 module_exit(rds_rdma_exit);
319
320 MODULE_AUTHOR("Oracle Corporation <rds-devel@oss.oracle.com>");
321 MODULE_DESCRIPTION("RDS: IB transport");
322 MODULE_LICENSE("Dual BSD/GPL");
323
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