xref: /openbmc/linux/include/rdma/rdma_cm.h (revision 22246614)
1 /*
2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
3  * Copyright (c) 2005 Intel Corporation.  All rights reserved.
4  *
5  * This Software is licensed under one of the following licenses:
6  *
7  * 1) under the terms of the "Common Public License 1.0" a copy of which is
8  *    available from the Open Source Initiative, see
9  *    http://www.opensource.org/licenses/cpl.php.
10  *
11  * 2) under the terms of the "The BSD License" a copy of which is
12  *    available from the Open Source Initiative, see
13  *    http://www.opensource.org/licenses/bsd-license.php.
14  *
15  * 3) under the terms of the "GNU General Public License (GPL) Version 2" a
16  *    copy of which is available from the Open Source Initiative, see
17  *    http://www.opensource.org/licenses/gpl-license.php.
18  *
19  * Licensee has the right to choose one of the above licenses.
20  *
21  * Redistributions of source code must retain the above copyright
22  * notice and one of the license notices.
23  *
24  * Redistributions in binary form must reproduce both the above copyright
25  * notice, one of the license notices in the documentation
26  * and/or other materials provided with the distribution.
27  *
28  */
29 
30 #if !defined(RDMA_CM_H)
31 #define RDMA_CM_H
32 
33 #include <linux/socket.h>
34 #include <linux/in6.h>
35 #include <rdma/ib_addr.h>
36 #include <rdma/ib_sa.h>
37 
38 /*
39  * Upon receiving a device removal event, users must destroy the associated
40  * RDMA identifier and release all resources allocated with the device.
41  */
42 enum rdma_cm_event_type {
43 	RDMA_CM_EVENT_ADDR_RESOLVED,
44 	RDMA_CM_EVENT_ADDR_ERROR,
45 	RDMA_CM_EVENT_ROUTE_RESOLVED,
46 	RDMA_CM_EVENT_ROUTE_ERROR,
47 	RDMA_CM_EVENT_CONNECT_REQUEST,
48 	RDMA_CM_EVENT_CONNECT_RESPONSE,
49 	RDMA_CM_EVENT_CONNECT_ERROR,
50 	RDMA_CM_EVENT_UNREACHABLE,
51 	RDMA_CM_EVENT_REJECTED,
52 	RDMA_CM_EVENT_ESTABLISHED,
53 	RDMA_CM_EVENT_DISCONNECTED,
54 	RDMA_CM_EVENT_DEVICE_REMOVAL,
55 	RDMA_CM_EVENT_MULTICAST_JOIN,
56 	RDMA_CM_EVENT_MULTICAST_ERROR
57 };
58 
59 enum rdma_port_space {
60 	RDMA_PS_SDP  = 0x0001,
61 	RDMA_PS_IPOIB= 0x0002,
62 	RDMA_PS_TCP  = 0x0106,
63 	RDMA_PS_UDP  = 0x0111,
64 	RDMA_PS_SCTP = 0x0183
65 };
66 
67 struct rdma_addr {
68 	struct sockaddr src_addr;
69 	u8		src_pad[sizeof(struct sockaddr_in6) -
70 				sizeof(struct sockaddr)];
71 	struct sockaddr dst_addr;
72 	u8		dst_pad[sizeof(struct sockaddr_in6) -
73 				sizeof(struct sockaddr)];
74 	struct rdma_dev_addr dev_addr;
75 };
76 
77 struct rdma_route {
78 	struct rdma_addr addr;
79 	struct ib_sa_path_rec *path_rec;
80 	int num_paths;
81 };
82 
83 struct rdma_conn_param {
84 	const void *private_data;
85 	u8 private_data_len;
86 	u8 responder_resources;
87 	u8 initiator_depth;
88 	u8 flow_control;
89 	u8 retry_count;		/* ignored when accepting */
90 	u8 rnr_retry_count;
91 	/* Fields below ignored if a QP is created on the rdma_cm_id. */
92 	u8 srq;
93 	u32 qp_num;
94 };
95 
96 struct rdma_ud_param {
97 	const void *private_data;
98 	u8 private_data_len;
99 	struct ib_ah_attr ah_attr;
100 	u32 qp_num;
101 	u32 qkey;
102 };
103 
104 struct rdma_cm_event {
105 	enum rdma_cm_event_type	 event;
106 	int			 status;
107 	union {
108 		struct rdma_conn_param	conn;
109 		struct rdma_ud_param	ud;
110 	} param;
111 };
112 
113 struct rdma_cm_id;
114 
115 /**
116  * rdma_cm_event_handler - Callback used to report user events.
117  *
118  * Notes: Users may not call rdma_destroy_id from this callback to destroy
119  *   the passed in id, or a corresponding listen id.  Returning a
120  *   non-zero value from the callback will destroy the passed in id.
121  */
122 typedef int (*rdma_cm_event_handler)(struct rdma_cm_id *id,
123 				     struct rdma_cm_event *event);
124 
125 struct rdma_cm_id {
126 	struct ib_device	*device;
127 	void			*context;
128 	struct ib_qp		*qp;
129 	rdma_cm_event_handler	 event_handler;
130 	struct rdma_route	 route;
131 	enum rdma_port_space	 ps;
132 	u8			 port_num;
133 };
134 
135 /**
136  * rdma_create_id - Create an RDMA identifier.
137  *
138  * @event_handler: User callback invoked to report events associated with the
139  *   returned rdma_id.
140  * @context: User specified context associated with the id.
141  * @ps: RDMA port space.
142  */
143 struct rdma_cm_id *rdma_create_id(rdma_cm_event_handler event_handler,
144 				  void *context, enum rdma_port_space ps);
145 
146 /**
147   * rdma_destroy_id - Destroys an RDMA identifier.
148   *
149   * @id: RDMA identifier.
150   *
151   * Note: calling this function has the effect of canceling in-flight
152   * asynchronous operations associated with the id.
153   */
154 void rdma_destroy_id(struct rdma_cm_id *id);
155 
156 /**
157  * rdma_bind_addr - Bind an RDMA identifier to a source address and
158  *   associated RDMA device, if needed.
159  *
160  * @id: RDMA identifier.
161  * @addr: Local address information.  Wildcard values are permitted.
162  *
163  * This associates a source address with the RDMA identifier before calling
164  * rdma_listen.  If a specific local address is given, the RDMA identifier will
165  * be bound to a local RDMA device.
166  */
167 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr);
168 
169 /**
170  * rdma_resolve_addr - Resolve destination and optional source addresses
171  *   from IP addresses to an RDMA address.  If successful, the specified
172  *   rdma_cm_id will be bound to a local device.
173  *
174  * @id: RDMA identifier.
175  * @src_addr: Source address information.  This parameter may be NULL.
176  * @dst_addr: Destination address information.
177  * @timeout_ms: Time to wait for resolution to complete.
178  */
179 int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
180 		      struct sockaddr *dst_addr, int timeout_ms);
181 
182 /**
183  * rdma_resolve_route - Resolve the RDMA address bound to the RDMA identifier
184  *   into route information needed to establish a connection.
185  *
186  * This is called on the client side of a connection.
187  * Users must have first called rdma_resolve_addr to resolve a dst_addr
188  * into an RDMA address before calling this routine.
189  */
190 int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms);
191 
192 /**
193  * rdma_create_qp - Allocate a QP and associate it with the specified RDMA
194  * identifier.
195  *
196  * QPs allocated to an rdma_cm_id will automatically be transitioned by the CMA
197  * through their states.
198  */
199 int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
200 		   struct ib_qp_init_attr *qp_init_attr);
201 
202 /**
203  * rdma_destroy_qp - Deallocate the QP associated with the specified RDMA
204  * identifier.
205  *
206  * Users must destroy any QP associated with an RDMA identifier before
207  * destroying the RDMA ID.
208  */
209 void rdma_destroy_qp(struct rdma_cm_id *id);
210 
211 /**
212  * rdma_init_qp_attr - Initializes the QP attributes for use in transitioning
213  *   to a specified QP state.
214  * @id: Communication identifier associated with the QP attributes to
215  *   initialize.
216  * @qp_attr: On input, specifies the desired QP state.  On output, the
217  *   mandatory and desired optional attributes will be set in order to
218  *   modify the QP to the specified state.
219  * @qp_attr_mask: The QP attribute mask that may be used to transition the
220  *   QP to the specified state.
221  *
222  * Users must set the @qp_attr->qp_state to the desired QP state.  This call
223  * will set all required attributes for the given transition, along with
224  * known optional attributes.  Users may override the attributes returned from
225  * this call before calling ib_modify_qp.
226  *
227  * Users that wish to have their QP automatically transitioned through its
228  * states can associate a QP with the rdma_cm_id by calling rdma_create_qp().
229  */
230 int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
231 		       int *qp_attr_mask);
232 
233 /**
234  * rdma_connect - Initiate an active connection request.
235  * @id: Connection identifier to connect.
236  * @conn_param: Connection information used for connected QPs.
237  *
238  * Users must have resolved a route for the rdma_cm_id to connect with
239  * by having called rdma_resolve_route before calling this routine.
240  *
241  * This call will either connect to a remote QP or obtain remote QP
242  * information for unconnected rdma_cm_id's.  The actual operation is
243  * based on the rdma_cm_id's port space.
244  */
245 int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
246 
247 /**
248  * rdma_listen - This function is called by the passive side to
249  *   listen for incoming connection requests.
250  *
251  * Users must have bound the rdma_cm_id to a local address by calling
252  * rdma_bind_addr before calling this routine.
253  */
254 int rdma_listen(struct rdma_cm_id *id, int backlog);
255 
256 /**
257  * rdma_accept - Called to accept a connection request or response.
258  * @id: Connection identifier associated with the request.
259  * @conn_param: Information needed to establish the connection.  This must be
260  *   provided if accepting a connection request.  If accepting a connection
261  *   response, this parameter must be NULL.
262  *
263  * Typically, this routine is only called by the listener to accept a connection
264  * request.  It must also be called on the active side of a connection if the
265  * user is performing their own QP transitions.
266  *
267  * In the case of error, a reject message is sent to the remote side and the
268  * state of the qp associated with the id is modified to error, such that any
269  * previously posted receive buffers would be flushed.
270  */
271 int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
272 
273 /**
274  * rdma_notify - Notifies the RDMA CM of an asynchronous event that has
275  * occurred on the connection.
276  * @id: Connection identifier to transition to established.
277  * @event: Asynchronous event.
278  *
279  * This routine should be invoked by users to notify the CM of relevant
280  * communication events.  Events that should be reported to the CM and
281  * when to report them are:
282  *
283  * IB_EVENT_COMM_EST - Used when a message is received on a connected
284  *    QP before an RTU has been received.
285  */
286 int rdma_notify(struct rdma_cm_id *id, enum ib_event_type event);
287 
288 /**
289  * rdma_reject - Called to reject a connection request or response.
290  */
291 int rdma_reject(struct rdma_cm_id *id, const void *private_data,
292 		u8 private_data_len);
293 
294 /**
295  * rdma_disconnect - This function disconnects the associated QP and
296  *   transitions it into the error state.
297  */
298 int rdma_disconnect(struct rdma_cm_id *id);
299 
300 /**
301  * rdma_join_multicast - Join the multicast group specified by the given
302  *   address.
303  * @id: Communication identifier associated with the request.
304  * @addr: Multicast address identifying the group to join.
305  * @context: User-defined context associated with the join request, returned
306  * to the user through the private_data pointer in multicast events.
307  */
308 int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
309 			void *context);
310 
311 /**
312  * rdma_leave_multicast - Leave the multicast group specified by the given
313  *   address.
314  */
315 void rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr);
316 
317 /**
318  * rdma_set_service_type - Set the type of service associated with a
319  *   connection identifier.
320  * @id: Communication identifier to associated with service type.
321  * @tos: Type of service.
322  *
323  * The type of service is interpretted as a differentiated service
324  * field (RFC 2474).  The service type should be specified before
325  * performing route resolution, as existing communication on the
326  * connection identifier may be unaffected.  The type of service
327  * requested may not be supported by the network to all destinations.
328  */
329 void rdma_set_service_type(struct rdma_cm_id *id, int tos);
330 
331 #endif /* RDMA_CM_H */
332