xref: /openbmc/linux/include/rdma/rdma_cm.h (revision 545e4006)
1 /*
2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
3  * Copyright (c) 2005 Intel Corporation.  All rights reserved.
4  *
5  * This software is available to you under a choice of one of two
6  * licenses.  You may choose to be licensed under the terms of the GNU
7  * General Public License (GPL) Version 2, available from the file
8  * COPYING in the main directory of this source tree, or the
9  * OpenIB.org BSD license below:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      - Redistributions of source code must retain the above
16  *        copyright notice, this list of conditions and the following
17  *        disclaimer.
18  *
19  *      - Redistributions in binary form must reproduce the above
20  *        copyright notice, this list of conditions and the following
21  *        disclaimer in the documentation and/or other materials
22  *        provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #if !defined(RDMA_CM_H)
35 #define RDMA_CM_H
36 
37 #include <linux/socket.h>
38 #include <linux/in6.h>
39 #include <rdma/ib_addr.h>
40 #include <rdma/ib_sa.h>
41 
42 /*
43  * Upon receiving a device removal event, users must destroy the associated
44  * RDMA identifier and release all resources allocated with the device.
45  */
46 enum rdma_cm_event_type {
47 	RDMA_CM_EVENT_ADDR_RESOLVED,
48 	RDMA_CM_EVENT_ADDR_ERROR,
49 	RDMA_CM_EVENT_ROUTE_RESOLVED,
50 	RDMA_CM_EVENT_ROUTE_ERROR,
51 	RDMA_CM_EVENT_CONNECT_REQUEST,
52 	RDMA_CM_EVENT_CONNECT_RESPONSE,
53 	RDMA_CM_EVENT_CONNECT_ERROR,
54 	RDMA_CM_EVENT_UNREACHABLE,
55 	RDMA_CM_EVENT_REJECTED,
56 	RDMA_CM_EVENT_ESTABLISHED,
57 	RDMA_CM_EVENT_DISCONNECTED,
58 	RDMA_CM_EVENT_DEVICE_REMOVAL,
59 	RDMA_CM_EVENT_MULTICAST_JOIN,
60 	RDMA_CM_EVENT_MULTICAST_ERROR,
61 	RDMA_CM_EVENT_ADDR_CHANGE,
62 	RDMA_CM_EVENT_TIMEWAIT_EXIT
63 };
64 
65 enum rdma_port_space {
66 	RDMA_PS_SDP   = 0x0001,
67 	RDMA_PS_IPOIB = 0x0002,
68 	RDMA_PS_TCP   = 0x0106,
69 	RDMA_PS_UDP   = 0x0111,
70 	RDMA_PS_SCTP  = 0x0183
71 };
72 
73 struct rdma_addr {
74 	struct sockaddr src_addr;
75 	u8		src_pad[sizeof(struct sockaddr_in6) -
76 				sizeof(struct sockaddr)];
77 	struct sockaddr dst_addr;
78 	u8		dst_pad[sizeof(struct sockaddr_in6) -
79 				sizeof(struct sockaddr)];
80 	struct rdma_dev_addr dev_addr;
81 };
82 
83 struct rdma_route {
84 	struct rdma_addr addr;
85 	struct ib_sa_path_rec *path_rec;
86 	int num_paths;
87 };
88 
89 struct rdma_conn_param {
90 	const void *private_data;
91 	u8 private_data_len;
92 	u8 responder_resources;
93 	u8 initiator_depth;
94 	u8 flow_control;
95 	u8 retry_count;		/* ignored when accepting */
96 	u8 rnr_retry_count;
97 	/* Fields below ignored if a QP is created on the rdma_cm_id. */
98 	u8 srq;
99 	u32 qp_num;
100 };
101 
102 struct rdma_ud_param {
103 	const void *private_data;
104 	u8 private_data_len;
105 	struct ib_ah_attr ah_attr;
106 	u32 qp_num;
107 	u32 qkey;
108 };
109 
110 struct rdma_cm_event {
111 	enum rdma_cm_event_type	 event;
112 	int			 status;
113 	union {
114 		struct rdma_conn_param	conn;
115 		struct rdma_ud_param	ud;
116 	} param;
117 };
118 
119 struct rdma_cm_id;
120 
121 /**
122  * rdma_cm_event_handler - Callback used to report user events.
123  *
124  * Notes: Users may not call rdma_destroy_id from this callback to destroy
125  *   the passed in id, or a corresponding listen id.  Returning a
126  *   non-zero value from the callback will destroy the passed in id.
127  */
128 typedef int (*rdma_cm_event_handler)(struct rdma_cm_id *id,
129 				     struct rdma_cm_event *event);
130 
131 struct rdma_cm_id {
132 	struct ib_device	*device;
133 	void			*context;
134 	struct ib_qp		*qp;
135 	rdma_cm_event_handler	 event_handler;
136 	struct rdma_route	 route;
137 	enum rdma_port_space	 ps;
138 	u8			 port_num;
139 };
140 
141 /**
142  * rdma_create_id - Create an RDMA identifier.
143  *
144  * @event_handler: User callback invoked to report events associated with the
145  *   returned rdma_id.
146  * @context: User specified context associated with the id.
147  * @ps: RDMA port space.
148  */
149 struct rdma_cm_id *rdma_create_id(rdma_cm_event_handler event_handler,
150 				  void *context, enum rdma_port_space ps);
151 
152 /**
153   * rdma_destroy_id - Destroys an RDMA identifier.
154   *
155   * @id: RDMA identifier.
156   *
157   * Note: calling this function has the effect of canceling in-flight
158   * asynchronous operations associated with the id.
159   */
160 void rdma_destroy_id(struct rdma_cm_id *id);
161 
162 /**
163  * rdma_bind_addr - Bind an RDMA identifier to a source address and
164  *   associated RDMA device, if needed.
165  *
166  * @id: RDMA identifier.
167  * @addr: Local address information.  Wildcard values are permitted.
168  *
169  * This associates a source address with the RDMA identifier before calling
170  * rdma_listen.  If a specific local address is given, the RDMA identifier will
171  * be bound to a local RDMA device.
172  */
173 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr);
174 
175 /**
176  * rdma_resolve_addr - Resolve destination and optional source addresses
177  *   from IP addresses to an RDMA address.  If successful, the specified
178  *   rdma_cm_id will be bound to a local device.
179  *
180  * @id: RDMA identifier.
181  * @src_addr: Source address information.  This parameter may be NULL.
182  * @dst_addr: Destination address information.
183  * @timeout_ms: Time to wait for resolution to complete.
184  */
185 int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
186 		      struct sockaddr *dst_addr, int timeout_ms);
187 
188 /**
189  * rdma_resolve_route - Resolve the RDMA address bound to the RDMA identifier
190  *   into route information needed to establish a connection.
191  *
192  * This is called on the client side of a connection.
193  * Users must have first called rdma_resolve_addr to resolve a dst_addr
194  * into an RDMA address before calling this routine.
195  */
196 int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms);
197 
198 /**
199  * rdma_create_qp - Allocate a QP and associate it with the specified RDMA
200  * identifier.
201  *
202  * QPs allocated to an rdma_cm_id will automatically be transitioned by the CMA
203  * through their states.
204  */
205 int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
206 		   struct ib_qp_init_attr *qp_init_attr);
207 
208 /**
209  * rdma_destroy_qp - Deallocate the QP associated with the specified RDMA
210  * identifier.
211  *
212  * Users must destroy any QP associated with an RDMA identifier before
213  * destroying the RDMA ID.
214  */
215 void rdma_destroy_qp(struct rdma_cm_id *id);
216 
217 /**
218  * rdma_init_qp_attr - Initializes the QP attributes for use in transitioning
219  *   to a specified QP state.
220  * @id: Communication identifier associated with the QP attributes to
221  *   initialize.
222  * @qp_attr: On input, specifies the desired QP state.  On output, the
223  *   mandatory and desired optional attributes will be set in order to
224  *   modify the QP to the specified state.
225  * @qp_attr_mask: The QP attribute mask that may be used to transition the
226  *   QP to the specified state.
227  *
228  * Users must set the @qp_attr->qp_state to the desired QP state.  This call
229  * will set all required attributes for the given transition, along with
230  * known optional attributes.  Users may override the attributes returned from
231  * this call before calling ib_modify_qp.
232  *
233  * Users that wish to have their QP automatically transitioned through its
234  * states can associate a QP with the rdma_cm_id by calling rdma_create_qp().
235  */
236 int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
237 		       int *qp_attr_mask);
238 
239 /**
240  * rdma_connect - Initiate an active connection request.
241  * @id: Connection identifier to connect.
242  * @conn_param: Connection information used for connected QPs.
243  *
244  * Users must have resolved a route for the rdma_cm_id to connect with
245  * by having called rdma_resolve_route before calling this routine.
246  *
247  * This call will either connect to a remote QP or obtain remote QP
248  * information for unconnected rdma_cm_id's.  The actual operation is
249  * based on the rdma_cm_id's port space.
250  */
251 int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
252 
253 /**
254  * rdma_listen - This function is called by the passive side to
255  *   listen for incoming connection requests.
256  *
257  * Users must have bound the rdma_cm_id to a local address by calling
258  * rdma_bind_addr before calling this routine.
259  */
260 int rdma_listen(struct rdma_cm_id *id, int backlog);
261 
262 /**
263  * rdma_accept - Called to accept a connection request or response.
264  * @id: Connection identifier associated with the request.
265  * @conn_param: Information needed to establish the connection.  This must be
266  *   provided if accepting a connection request.  If accepting a connection
267  *   response, this parameter must be NULL.
268  *
269  * Typically, this routine is only called by the listener to accept a connection
270  * request.  It must also be called on the active side of a connection if the
271  * user is performing their own QP transitions.
272  *
273  * In the case of error, a reject message is sent to the remote side and the
274  * state of the qp associated with the id is modified to error, such that any
275  * previously posted receive buffers would be flushed.
276  */
277 int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
278 
279 /**
280  * rdma_notify - Notifies the RDMA CM of an asynchronous event that has
281  * occurred on the connection.
282  * @id: Connection identifier to transition to established.
283  * @event: Asynchronous event.
284  *
285  * This routine should be invoked by users to notify the CM of relevant
286  * communication events.  Events that should be reported to the CM and
287  * when to report them are:
288  *
289  * IB_EVENT_COMM_EST - Used when a message is received on a connected
290  *    QP before an RTU has been received.
291  */
292 int rdma_notify(struct rdma_cm_id *id, enum ib_event_type event);
293 
294 /**
295  * rdma_reject - Called to reject a connection request or response.
296  */
297 int rdma_reject(struct rdma_cm_id *id, const void *private_data,
298 		u8 private_data_len);
299 
300 /**
301  * rdma_disconnect - This function disconnects the associated QP and
302  *   transitions it into the error state.
303  */
304 int rdma_disconnect(struct rdma_cm_id *id);
305 
306 /**
307  * rdma_join_multicast - Join the multicast group specified by the given
308  *   address.
309  * @id: Communication identifier associated with the request.
310  * @addr: Multicast address identifying the group to join.
311  * @context: User-defined context associated with the join request, returned
312  * to the user through the private_data pointer in multicast events.
313  */
314 int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
315 			void *context);
316 
317 /**
318  * rdma_leave_multicast - Leave the multicast group specified by the given
319  *   address.
320  */
321 void rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr);
322 
323 /**
324  * rdma_set_service_type - Set the type of service associated with a
325  *   connection identifier.
326  * @id: Communication identifier to associated with service type.
327  * @tos: Type of service.
328  *
329  * The type of service is interpretted as a differentiated service
330  * field (RFC 2474).  The service type should be specified before
331  * performing route resolution, as existing communication on the
332  * connection identifier may be unaffected.  The type of service
333  * requested may not be supported by the network to all destinations.
334  */
335 void rdma_set_service_type(struct rdma_cm_id *id, int tos);
336 
337 #endif /* RDMA_CM_H */
338