xref: /openbmc/linux/include/rdma/rdma_cm.h (revision 54525552)
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 };
71 
72 struct rdma_addr {
73 	struct sockaddr_storage src_addr;
74 	struct sockaddr_storage dst_addr;
75 	struct rdma_dev_addr dev_addr;
76 };
77 
78 struct rdma_route {
79 	struct rdma_addr addr;
80 	struct ib_sa_path_rec *path_rec;
81 	int num_paths;
82 };
83 
84 struct rdma_conn_param {
85 	const void *private_data;
86 	u8 private_data_len;
87 	u8 responder_resources;
88 	u8 initiator_depth;
89 	u8 flow_control;
90 	u8 retry_count;		/* ignored when accepting */
91 	u8 rnr_retry_count;
92 	/* Fields below ignored if a QP is created on the rdma_cm_id. */
93 	u8 srq;
94 	u32 qp_num;
95 };
96 
97 struct rdma_ud_param {
98 	const void *private_data;
99 	u8 private_data_len;
100 	struct ib_ah_attr ah_attr;
101 	u32 qp_num;
102 	u32 qkey;
103 };
104 
105 struct rdma_cm_event {
106 	enum rdma_cm_event_type	 event;
107 	int			 status;
108 	union {
109 		struct rdma_conn_param	conn;
110 		struct rdma_ud_param	ud;
111 	} param;
112 };
113 
114 struct rdma_cm_id;
115 
116 /**
117  * rdma_cm_event_handler - Callback used to report user events.
118  *
119  * Notes: Users may not call rdma_destroy_id from this callback to destroy
120  *   the passed in id, or a corresponding listen id.  Returning a
121  *   non-zero value from the callback will destroy the passed in id.
122  */
123 typedef int (*rdma_cm_event_handler)(struct rdma_cm_id *id,
124 				     struct rdma_cm_event *event);
125 
126 struct rdma_cm_id {
127 	struct ib_device	*device;
128 	void			*context;
129 	struct ib_qp		*qp;
130 	rdma_cm_event_handler	 event_handler;
131 	struct rdma_route	 route;
132 	enum rdma_port_space	 ps;
133 	u8			 port_num;
134 };
135 
136 /**
137  * rdma_create_id - Create an RDMA identifier.
138  *
139  * @event_handler: User callback invoked to report events associated with the
140  *   returned rdma_id.
141  * @context: User specified context associated with the id.
142  * @ps: RDMA port space.
143  */
144 struct rdma_cm_id *rdma_create_id(rdma_cm_event_handler event_handler,
145 				  void *context, enum rdma_port_space ps);
146 
147 /**
148   * rdma_destroy_id - Destroys an RDMA identifier.
149   *
150   * @id: RDMA identifier.
151   *
152   * Note: calling this function has the effect of canceling in-flight
153   * asynchronous operations associated with the id.
154   */
155 void rdma_destroy_id(struct rdma_cm_id *id);
156 
157 /**
158  * rdma_bind_addr - Bind an RDMA identifier to a source address and
159  *   associated RDMA device, if needed.
160  *
161  * @id: RDMA identifier.
162  * @addr: Local address information.  Wildcard values are permitted.
163  *
164  * This associates a source address with the RDMA identifier before calling
165  * rdma_listen.  If a specific local address is given, the RDMA identifier will
166  * be bound to a local RDMA device.
167  */
168 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr);
169 
170 /**
171  * rdma_resolve_addr - Resolve destination and optional source addresses
172  *   from IP addresses to an RDMA address.  If successful, the specified
173  *   rdma_cm_id will be bound to a local device.
174  *
175  * @id: RDMA identifier.
176  * @src_addr: Source address information.  This parameter may be NULL.
177  * @dst_addr: Destination address information.
178  * @timeout_ms: Time to wait for resolution to complete.
179  */
180 int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
181 		      struct sockaddr *dst_addr, int timeout_ms);
182 
183 /**
184  * rdma_resolve_route - Resolve the RDMA address bound to the RDMA identifier
185  *   into route information needed to establish a connection.
186  *
187  * This is called on the client side of a connection.
188  * Users must have first called rdma_resolve_addr to resolve a dst_addr
189  * into an RDMA address before calling this routine.
190  */
191 int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms);
192 
193 /**
194  * rdma_create_qp - Allocate a QP and associate it with the specified RDMA
195  * identifier.
196  *
197  * QPs allocated to an rdma_cm_id will automatically be transitioned by the CMA
198  * through their states.
199  */
200 int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
201 		   struct ib_qp_init_attr *qp_init_attr);
202 
203 /**
204  * rdma_destroy_qp - Deallocate the QP associated with the specified RDMA
205  * identifier.
206  *
207  * Users must destroy any QP associated with an RDMA identifier before
208  * destroying the RDMA ID.
209  */
210 void rdma_destroy_qp(struct rdma_cm_id *id);
211 
212 /**
213  * rdma_init_qp_attr - Initializes the QP attributes for use in transitioning
214  *   to a specified QP state.
215  * @id: Communication identifier associated with the QP attributes to
216  *   initialize.
217  * @qp_attr: On input, specifies the desired QP state.  On output, the
218  *   mandatory and desired optional attributes will be set in order to
219  *   modify the QP to the specified state.
220  * @qp_attr_mask: The QP attribute mask that may be used to transition the
221  *   QP to the specified state.
222  *
223  * Users must set the @qp_attr->qp_state to the desired QP state.  This call
224  * will set all required attributes for the given transition, along with
225  * known optional attributes.  Users may override the attributes returned from
226  * this call before calling ib_modify_qp.
227  *
228  * Users that wish to have their QP automatically transitioned through its
229  * states can associate a QP with the rdma_cm_id by calling rdma_create_qp().
230  */
231 int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
232 		       int *qp_attr_mask);
233 
234 /**
235  * rdma_connect - Initiate an active connection request.
236  * @id: Connection identifier to connect.
237  * @conn_param: Connection information used for connected QPs.
238  *
239  * Users must have resolved a route for the rdma_cm_id to connect with
240  * by having called rdma_resolve_route before calling this routine.
241  *
242  * This call will either connect to a remote QP or obtain remote QP
243  * information for unconnected rdma_cm_id's.  The actual operation is
244  * based on the rdma_cm_id's port space.
245  */
246 int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
247 
248 /**
249  * rdma_listen - This function is called by the passive side to
250  *   listen for incoming connection requests.
251  *
252  * Users must have bound the rdma_cm_id to a local address by calling
253  * rdma_bind_addr before calling this routine.
254  */
255 int rdma_listen(struct rdma_cm_id *id, int backlog);
256 
257 /**
258  * rdma_accept - Called to accept a connection request or response.
259  * @id: Connection identifier associated with the request.
260  * @conn_param: Information needed to establish the connection.  This must be
261  *   provided if accepting a connection request.  If accepting a connection
262  *   response, this parameter must be NULL.
263  *
264  * Typically, this routine is only called by the listener to accept a connection
265  * request.  It must also be called on the active side of a connection if the
266  * user is performing their own QP transitions.
267  *
268  * In the case of error, a reject message is sent to the remote side and the
269  * state of the qp associated with the id is modified to error, such that any
270  * previously posted receive buffers would be flushed.
271  */
272 int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
273 
274 /**
275  * rdma_notify - Notifies the RDMA CM of an asynchronous event that has
276  * occurred on the connection.
277  * @id: Connection identifier to transition to established.
278  * @event: Asynchronous event.
279  *
280  * This routine should be invoked by users to notify the CM of relevant
281  * communication events.  Events that should be reported to the CM and
282  * when to report them are:
283  *
284  * IB_EVENT_COMM_EST - Used when a message is received on a connected
285  *    QP before an RTU has been received.
286  */
287 int rdma_notify(struct rdma_cm_id *id, enum ib_event_type event);
288 
289 /**
290  * rdma_reject - Called to reject a connection request or response.
291  */
292 int rdma_reject(struct rdma_cm_id *id, const void *private_data,
293 		u8 private_data_len);
294 
295 /**
296  * rdma_disconnect - This function disconnects the associated QP and
297  *   transitions it into the error state.
298  */
299 int rdma_disconnect(struct rdma_cm_id *id);
300 
301 /**
302  * rdma_join_multicast - Join the multicast group specified by the given
303  *   address.
304  * @id: Communication identifier associated with the request.
305  * @addr: Multicast address identifying the group to join.
306  * @context: User-defined context associated with the join request, returned
307  * to the user through the private_data pointer in multicast events.
308  */
309 int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
310 			void *context);
311 
312 /**
313  * rdma_leave_multicast - Leave the multicast group specified by the given
314  *   address.
315  */
316 void rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr);
317 
318 /**
319  * rdma_set_service_type - Set the type of service associated with a
320  *   connection identifier.
321  * @id: Communication identifier to associated with service type.
322  * @tos: Type of service.
323  *
324  * The type of service is interpretted as a differentiated service
325  * field (RFC 2474).  The service type should be specified before
326  * performing route resolution, as existing communication on the
327  * connection identifier may be unaffected.  The type of service
328  * requested may not be supported by the network to all destinations.
329  */
330 void rdma_set_service_type(struct rdma_cm_id *id, int tos);
331 
332 /**
333  * rdma_set_reuseaddr - Allow the reuse of local addresses when binding
334  *    the rdma_cm_id.
335  * @id: Communication identifier to configure.
336  * @reuse: Value indicating if the bound address is reusable.
337  *
338  * Reuse must be set before an address is bound to the id.
339  */
340 int rdma_set_reuseaddr(struct rdma_cm_id *id, int reuse);
341 
342 #endif /* RDMA_CM_H */
343