xref: /freebsd/contrib/ofed/librdmacm/rdma_cma.h (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1 /*
2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
3  * Copyright (c) 2005-2014 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_CMA_H)
35 #define RDMA_CMA_H
36 
37 #include <netinet/in.h>
38 #include <sys/socket.h>
39 #include <infiniband/verbs.h>
40 #include <infiniband/sa.h>
41 
42 #ifdef __cplusplus
43 extern "C" {
44 #endif
45 
46 /*
47  * Upon receiving a device removal event, users must destroy the associated
48  * RDMA identifier and release all resources allocated with the device.
49  */
50 enum rdma_cm_event_type {
51 	RDMA_CM_EVENT_ADDR_RESOLVED,
52 	RDMA_CM_EVENT_ADDR_ERROR,
53 	RDMA_CM_EVENT_ROUTE_RESOLVED,
54 	RDMA_CM_EVENT_ROUTE_ERROR,
55 	RDMA_CM_EVENT_CONNECT_REQUEST,
56 	RDMA_CM_EVENT_CONNECT_RESPONSE,
57 	RDMA_CM_EVENT_CONNECT_ERROR,
58 	RDMA_CM_EVENT_UNREACHABLE,
59 	RDMA_CM_EVENT_REJECTED,
60 	RDMA_CM_EVENT_ESTABLISHED,
61 	RDMA_CM_EVENT_DISCONNECTED,
62 	RDMA_CM_EVENT_DEVICE_REMOVAL,
63 	RDMA_CM_EVENT_MULTICAST_JOIN,
64 	RDMA_CM_EVENT_MULTICAST_ERROR,
65 	RDMA_CM_EVENT_ADDR_CHANGE,
66 	RDMA_CM_EVENT_TIMEWAIT_EXIT
67 };
68 
69 enum rdma_port_space {
70 	RDMA_PS_IPOIB = 0x0002,
71 	RDMA_PS_TCP   = 0x0106,
72 	RDMA_PS_UDP   = 0x0111,
73 	RDMA_PS_IB    = 0x013F,
74 };
75 
76 #define RDMA_IB_IP_PS_MASK   0xFFFFFFFFFFFF0000ULL
77 #define RDMA_IB_IP_PORT_MASK 0x000000000000FFFFULL
78 #define RDMA_IB_IP_PS_TCP    0x0000000001060000ULL
79 #define RDMA_IB_IP_PS_UDP    0x0000000001110000ULL
80 #define RDMA_IB_PS_IB        0x00000000013F0000ULL
81 
82 /*
83  * Global qkey value for UDP QPs and multicast groups created via the
84  * RDMA CM.
85  */
86 #define RDMA_UDP_QKEY 0x01234567
87 
88 struct rdma_ib_addr {
89 	union ibv_gid	sgid;
90 	union ibv_gid	dgid;
91 	__be16		pkey;
92 };
93 
94 struct rdma_addr {
95 	union {
96 		struct sockaddr		src_addr;
97 		struct sockaddr_in	src_sin;
98 		struct sockaddr_in6	src_sin6;
99 		struct sockaddr_storage src_storage;
100 	};
101 	union {
102 		struct sockaddr		dst_addr;
103 		struct sockaddr_in	dst_sin;
104 		struct sockaddr_in6	dst_sin6;
105 		struct sockaddr_storage dst_storage;
106 	};
107 	union {
108 		struct rdma_ib_addr	ibaddr;
109 	} addr;
110 };
111 
112 struct rdma_route {
113 	struct rdma_addr	 addr;
114 	struct ibv_sa_path_rec	*path_rec;
115 	int			 num_paths;
116 };
117 
118 struct rdma_event_channel {
119 	int			fd;
120 };
121 
122 struct rdma_cm_id {
123 	struct ibv_context	*verbs;
124 	struct rdma_event_channel *channel;
125 	void			*context;
126 	struct ibv_qp		*qp;
127 	struct rdma_route	 route;
128 	enum rdma_port_space	 ps;
129 	uint8_t			 port_num;
130 	struct rdma_cm_event	*event;
131 	struct ibv_comp_channel *send_cq_channel;
132 	struct ibv_cq		*send_cq;
133 	struct ibv_comp_channel *recv_cq_channel;
134 	struct ibv_cq		*recv_cq;
135 	struct ibv_srq		*srq;
136 	struct ibv_pd		*pd;
137 	enum ibv_qp_type	qp_type;
138 };
139 
140 enum {
141 	RDMA_MAX_RESP_RES = 0xFF,
142 	RDMA_MAX_INIT_DEPTH = 0xFF
143 };
144 
145 struct rdma_conn_param {
146 	const void *private_data;
147 	uint8_t private_data_len;
148 	uint8_t responder_resources;
149 	uint8_t initiator_depth;
150 	uint8_t flow_control;
151 	uint8_t retry_count;		/* ignored when accepting */
152 	uint8_t rnr_retry_count;
153 	/* Fields below ignored if a QP is created on the rdma_cm_id. */
154 	uint8_t srq;
155 	uint32_t qp_num;
156 };
157 
158 struct rdma_ud_param {
159 	const void *private_data;
160 	uint8_t private_data_len;
161 	struct ibv_ah_attr ah_attr;
162 	uint32_t qp_num;
163 	uint32_t qkey;
164 };
165 
166 struct rdma_cm_event {
167 	struct rdma_cm_id	*id;
168 	struct rdma_cm_id	*listen_id;
169 	enum rdma_cm_event_type	 event;
170 	int			 status;
171 	union {
172 		struct rdma_conn_param conn;
173 		struct rdma_ud_param   ud;
174 	} param;
175 };
176 
177 #define RAI_PASSIVE		0x00000001
178 #define RAI_NUMERICHOST		0x00000002
179 #define RAI_NOROUTE		0x00000004
180 #define RAI_FAMILY		0x00000008
181 
182 struct rdma_addrinfo {
183 	int			ai_flags;
184 	int			ai_family;
185 	int			ai_qp_type;
186 	int			ai_port_space;
187 	socklen_t		ai_src_len;
188 	socklen_t		ai_dst_len;
189 	struct sockaddr		*ai_src_addr;
190 	struct sockaddr		*ai_dst_addr;
191 	char			*ai_src_canonname;
192 	char			*ai_dst_canonname;
193 	size_t			ai_route_len;
194 	void			*ai_route;
195 	size_t			ai_connect_len;
196 	void			*ai_connect;
197 	struct rdma_addrinfo	*ai_next;
198 };
199 
200 /**
201  * rdma_create_event_channel - Open a channel used to report communication events.
202  * Description:
203  *   Asynchronous events are reported to users through event channels.  Each
204  *   event channel maps to a file descriptor.
205  * Notes:
206  *   All created event channels must be destroyed by calling
207  *   rdma_destroy_event_channel.  Users should call rdma_get_cm_event to
208  *   retrieve events on an event channel.
209  * See also:
210  *   rdma_get_cm_event, rdma_destroy_event_channel
211  */
212 struct rdma_event_channel *rdma_create_event_channel(void);
213 
214 /**
215  * rdma_destroy_event_channel - Close an event communication channel.
216  * @channel: The communication channel to destroy.
217  * Description:
218  *   Release all resources associated with an event channel and closes the
219  *   associated file descriptor.
220  * Notes:
221  *   All rdma_cm_id's associated with the event channel must be destroyed,
222  *   and all returned events must be acked before calling this function.
223  * See also:
224  *  rdma_create_event_channel, rdma_get_cm_event, rdma_ack_cm_event
225  */
226 void rdma_destroy_event_channel(struct rdma_event_channel *channel);
227 
228 /**
229  * rdma_create_id - Allocate a communication identifier.
230  * @channel: The communication channel that events associated with the
231  *   allocated rdma_cm_id will be reported on.
232  * @id: A reference where the allocated communication identifier will be
233  *   returned.
234  * @context: User specified context associated with the rdma_cm_id.
235  * @ps: RDMA port space.
236  * Description:
237  *   Creates an identifier that is used to track communication information.
238  * Notes:
239  *   Rdma_cm_id's are conceptually equivalent to a socket for RDMA
240  *   communication.  The difference is that RDMA communication requires
241  *   explicitly binding to a specified RDMA device before communication
242  *   can occur, and most operations are asynchronous in nature.  Communication
243  *   events on an rdma_cm_id are reported through the associated event
244  *   channel.  Users must release the rdma_cm_id by calling rdma_destroy_id.
245  * See also:
246  *   rdma_create_event_channel, rdma_destroy_id, rdma_get_devices,
247  *   rdma_bind_addr, rdma_resolve_addr, rdma_connect, rdma_listen,
248  */
249 int rdma_create_id(struct rdma_event_channel *channel,
250 		   struct rdma_cm_id **id, void *context,
251 		   enum rdma_port_space ps);
252 
253 /**
254  * rdma_create_ep - Allocate a communication identifier and qp.
255  * @id: A reference where the allocated communication identifier will be
256  *   returned.
257  * @res: Result from rdma_getaddrinfo, which specifies the source and
258  *   destination addresses, plus optional routing and connection information.
259  * @pd: Optional protection domain.  This parameter is ignored if qp_init_attr
260  *   is NULL.
261  * @qp_init_attr: Optional attributes for a QP created on the rdma_cm_id.
262  * Description:
263  *   Create an identifier and option QP used for communication.
264  * Notes:
265  *   If qp_init_attr is provided, then a queue pair will be allocated and
266  *   associated with the rdma_cm_id.  If a pd is provided, the QP will be
267  *   created on that PD.  Otherwise, the QP will be allocated on a default
268  *   PD.
269  *   The rdma_cm_id will be set to use synchronous operations (connect,
270  *   listen, and get_request).  To convert to asynchronous operation, the
271  *   rdma_cm_id should be migrated to a user allocated event channel.
272  * See also:
273  *   rdma_create_id, rdma_create_qp, rdma_migrate_id, rdma_connect,
274  *   rdma_listen
275  */
276 int rdma_create_ep(struct rdma_cm_id **id, struct rdma_addrinfo *res,
277 		   struct ibv_pd *pd, struct ibv_qp_init_attr *qp_init_attr);
278 
279 /**
280  * rdma_destroy_ep - Deallocates a communication identifier and qp.
281  * @id: The communication identifier to destroy.
282  * Description:
283  *   Destroys the specified rdma_cm_id and any associated QP created
284  *   on that id.
285  * See also:
286  *   rdma_create_ep
287  */
288 void rdma_destroy_ep(struct rdma_cm_id *id);
289 
290 /**
291  * rdma_destroy_id - Release a communication identifier.
292  * @id: The communication identifier to destroy.
293  * Description:
294  *   Destroys the specified rdma_cm_id and cancels any outstanding
295  *   asynchronous operation.
296  * Notes:
297  *   Users must free any associated QP with the rdma_cm_id before
298  *   calling this routine and ack an related events.
299  * See also:
300  *   rdma_create_id, rdma_destroy_qp, rdma_ack_cm_event
301  */
302 int rdma_destroy_id(struct rdma_cm_id *id);
303 
304 /**
305  * rdma_bind_addr - Bind an RDMA identifier to a source address.
306  * @id: RDMA identifier.
307  * @addr: Local address information.  Wildcard values are permitted.
308  * Description:
309  *   Associates a source address with an rdma_cm_id.  The address may be
310  *   wildcarded.  If binding to a specific local address, the rdma_cm_id
311  *   will also be bound to a local RDMA device.
312  * Notes:
313  *   Typically, this routine is called before calling rdma_listen to bind
314  *   to a specific port number, but it may also be called on the active side
315  *   of a connection before calling rdma_resolve_addr to bind to a specific
316  *   address.
317  * See also:
318  *   rdma_create_id, rdma_listen, rdma_resolve_addr, rdma_create_qp
319  */
320 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr);
321 
322 /**
323  * rdma_resolve_addr - Resolve destination and optional source addresses.
324  * @id: RDMA identifier.
325  * @src_addr: Source address information.  This parameter may be NULL.
326  * @dst_addr: Destination address information.
327  * @timeout_ms: Time to wait for resolution to complete.
328  * Description:
329  *   Resolve destination and optional source addresses from IP addresses
330  *   to an RDMA address.  If successful, the specified rdma_cm_id will
331  *   be bound to a local device.
332  * Notes:
333  *   This call is used to map a given destination IP address to a usable RDMA
334  *   address.  If a source address is given, the rdma_cm_id is bound to that
335  *   address, the same as if rdma_bind_addr were called.  If no source
336  *   address is given, and the rdma_cm_id has not yet been bound to a device,
337  *   then the rdma_cm_id will be bound to a source address based on the
338  *   local routing tables.  After this call, the rdma_cm_id will be bound to
339  *   an RDMA device.  This call is typically made from the active side of a
340  *   connection before calling rdma_resolve_route and rdma_connect.
341  * See also:
342  *   rdma_create_id, rdma_resolve_route, rdma_connect, rdma_create_qp,
343  *   rdma_get_cm_event, rdma_bind_addr
344  */
345 int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
346 		      struct sockaddr *dst_addr, int timeout_ms);
347 
348 /**
349  * rdma_resolve_route - Resolve the route information needed to establish a connection.
350  * @id: RDMA identifier.
351  * @timeout_ms: Time to wait for resolution to complete.
352  * Description:
353  *   Resolves an RDMA route to the destination address in order to establish
354  *   a connection.  The destination address must have already been resolved
355  *   by calling rdma_resolve_addr.
356  * Notes:
357  *   This is called on the client side of a connection after calling
358  *   rdma_resolve_addr, but before calling rdma_connect.
359  * See also:
360  *   rdma_resolve_addr, rdma_connect, rdma_get_cm_event
361  */
362 int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms);
363 
364 /**
365  * rdma_create_qp - Allocate a QP.
366  * @id: RDMA identifier.
367  * @pd: Optional protection domain for the QP.
368  * @qp_init_attr: initial QP attributes.
369  * Description:
370  *  Allocate a QP associated with the specified rdma_cm_id and transition it
371  *  for sending and receiving.
372  * Notes:
373  *   The rdma_cm_id must be bound to a local RDMA device before calling this
374  *   function, and the protection domain must be for that same device.
375  *   QPs allocated to an rdma_cm_id are automatically transitioned by the
376  *   librdmacm through their states.  After being allocated, the QP will be
377  *   ready to handle posting of receives.  If the QP is unconnected, it will
378  *   be ready to post sends.
379  *   If pd is NULL, then the QP will be allocated using a default protection
380  *   domain associated with the underlying RDMA device.
381  * See also:
382  *   rdma_bind_addr, rdma_resolve_addr, rdma_destroy_qp, ibv_create_qp,
383  *   ibv_modify_qp
384  */
385 int rdma_create_qp(struct rdma_cm_id *id, struct ibv_pd *pd,
386 		   struct ibv_qp_init_attr *qp_init_attr);
387 int rdma_create_qp_ex(struct rdma_cm_id *id,
388 		      struct ibv_qp_init_attr_ex *qp_init_attr);
389 
390 /**
391  * rdma_destroy_qp - Deallocate a QP.
392  * @id: RDMA identifier.
393  * Description:
394  *   Destroy a QP allocated on the rdma_cm_id.
395  * Notes:
396  *   Users must destroy any QP associated with an rdma_cm_id before
397  *   destroying the ID.
398  * See also:
399  *   rdma_create_qp, rdma_destroy_id, ibv_destroy_qp
400  */
401 void rdma_destroy_qp(struct rdma_cm_id *id);
402 
403 /**
404  * rdma_connect - Initiate an active connection request.
405  * @id: RDMA identifier.
406  * @conn_param: optional connection parameters.
407  * Description:
408  *   For a connected rdma_cm_id, this call initiates a connection request
409  *   to a remote destination.  For an unconnected rdma_cm_id, it initiates
410  *   a lookup of the remote QP providing the datagram service.
411  * Notes:
412  *   Users must have resolved a route to the destination address
413  *   by having called rdma_resolve_route before calling this routine.
414  *   A user may override the default connection parameters and exchange
415  *   private data as part of the connection by using the conn_param parameter.
416  * See also:
417  *   rdma_resolve_route, rdma_disconnect, rdma_listen, rdma_get_cm_event
418  */
419 int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
420 
421 /**
422  * rdma_listen - Listen for incoming connection requests.
423  * @id: RDMA identifier.
424  * @backlog: backlog of incoming connection requests.
425  * Description:
426  *   Initiates a listen for incoming connection requests or datagram service
427  *   lookup.  The listen will be restricted to the locally bound source
428  *   address.
429  * Notes:
430  *   Users must have bound the rdma_cm_id to a local address by calling
431  *   rdma_bind_addr before calling this routine.  If the rdma_cm_id is
432  *   bound to a specific IP address, the listen will be restricted to that
433  *   address and the associated RDMA device.  If the rdma_cm_id is bound
434  *   to an RDMA port number only, the listen will occur across all RDMA
435  *   devices.
436  * See also:
437  *   rdma_bind_addr, rdma_connect, rdma_accept, rdma_reject, rdma_get_cm_event
438  */
439 int rdma_listen(struct rdma_cm_id *id, int backlog);
440 
441 /**
442  * rdma_get_request
443  */
444 int rdma_get_request(struct rdma_cm_id *listen, struct rdma_cm_id **id);
445 
446 /**
447  * rdma_accept - Called to accept a connection request.
448  * @id: Connection identifier associated with the request.
449  * @conn_param: Optional information needed to establish the connection.
450  * Description:
451  *   Called from the listening side to accept a connection or datagram
452  *   service lookup request.
453  * Notes:
454  *   Unlike the socket accept routine, rdma_accept is not called on a
455  *   listening rdma_cm_id.  Instead, after calling rdma_listen, the user
456  *   waits for a connection request event to occur.  Connection request
457  *   events give the user a newly created rdma_cm_id, similar to a new
458  *   socket, but the rdma_cm_id is bound to a specific RDMA device.
459  *   rdma_accept is called on the new rdma_cm_id.
460  *   A user may override the default connection parameters and exchange
461  *   private data as part of the connection by using the conn_param parameter.
462  * See also:
463  *   rdma_listen, rdma_reject, rdma_get_cm_event
464  */
465 int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
466 
467 /**
468  * rdma_reject - Called to reject a connection request.
469  * @id: Connection identifier associated with the request.
470  * @private_data: Optional private data to send with the reject message.
471  * @private_data_len: Size of the private_data to send, in bytes.
472  * Description:
473  *   Called from the listening side to reject a connection or datagram
474  *   service lookup request.
475  * Notes:
476  *   After receiving a connection request event, a user may call rdma_reject
477  *   to reject the request.  If the underlying RDMA transport supports
478  *   private data in the reject message, the specified data will be passed to
479  *   the remote side.
480  * See also:
481  *   rdma_listen, rdma_accept, rdma_get_cm_event
482  */
483 int rdma_reject(struct rdma_cm_id *id, const void *private_data,
484 		uint8_t private_data_len);
485 
486 /**
487  * rdma_notify - Notifies the librdmacm of an asynchronous event.
488  * @id: RDMA identifier.
489  * @event: Asynchronous event.
490  * Description:
491  *   Used to notify the librdmacm of asynchronous events that have occurred
492  *   on a QP associated with the rdma_cm_id.
493  * Notes:
494  *   Asynchronous events that occur on a QP are reported through the user's
495  *   device event handler.  This routine is used to notify the librdmacm of
496  *   communication events.  In most cases, use of this routine is not
497  *   necessary, however if connection establishment is done out of band
498  *   (such as done through Infiniband), it's possible to receive data on a
499  *   QP that is not yet considered connected.  This routine forces the
500  *   connection into an established state in this case in order to handle
501  *   the rare situation where the connection never forms on its own.
502  *   Events that should be reported to the CM are: IB_EVENT_COMM_EST.
503  * See also:
504  *   rdma_connect, rdma_accept, rdma_listen
505  */
506 int rdma_notify(struct rdma_cm_id *id, enum ibv_event_type event);
507 
508 /**
509  * rdma_disconnect - This function disconnects a connection.
510  * @id: RDMA identifier.
511  * Description:
512  *   Disconnects a connection and transitions any associated QP to the
513  *   error state.
514  * See also:
515  *   rdma_connect, rdma_listen, rdma_accept
516  */
517 int rdma_disconnect(struct rdma_cm_id *id);
518 
519 /**
520  * rdma_join_multicast - Joins a multicast group.
521  * @id: Communication identifier associated with the request.
522  * @addr: Multicast address identifying the group to join.
523  * @context: User-defined context associated with the join request.
524  * Description:
525  *   Joins a multicast group and attaches an associated QP to the group.
526  * Notes:
527  *   Before joining a multicast group, the rdma_cm_id must be bound to
528  *   an RDMA device by calling rdma_bind_addr or rdma_resolve_addr.  Use of
529  *   rdma_resolve_addr requires the local routing tables to resolve the
530  *   multicast address to an RDMA device.  The user must call
531  *   rdma_leave_multicast to leave the multicast group and release any
532  *   multicast resources.  The context is returned to the user through
533  *   the private_data field in the rdma_cm_event.
534  * See also:
535  *   rdma_leave_multicast, rdma_bind_addr, rdma_resolve_addr, rdma_create_qp
536  */
537 int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
538 			void *context);
539 
540 /**
541  * rdma_leave_multicast - Leaves a multicast group.
542  * @id: Communication identifier associated with the request.
543  * @addr: Multicast address identifying the group to leave.
544  * Description:
545  *   Leaves a multicast group and detaches an associated QP from the group.
546  * Notes:
547  *   Calling this function before a group has been fully joined results in
548  *   canceling the join operation.  Users should be aware that messages
549  *   received from the multicast group may stilled be queued for
550  *   completion processing immediately after leaving a multicast group.
551  *   Destroying an rdma_cm_id will automatically leave all multicast groups.
552  * See also:
553  *   rdma_join_multicast, rdma_destroy_qp
554  */
555 int rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr);
556 
557 /**
558  * rdma_get_cm_event - Retrieves the next pending communication event.
559  * @channel: Event channel to check for events.
560  * @event: Allocated information about the next communication event.
561  * Description:
562  *   Retrieves a communication event.  If no events are pending, by default,
563  *   the call will block until an event is received.
564  * Notes:
565  *   The default synchronous behavior of this routine can be changed by
566  *   modifying the file descriptor associated with the given channel.  All
567  *   events that are reported must be acknowledged by calling rdma_ack_cm_event.
568  *   Destruction of an rdma_cm_id will block until related events have been
569  *   acknowledged.
570  * See also:
571  *   rdma_ack_cm_event, rdma_create_event_channel, rdma_event_str
572  */
573 int rdma_get_cm_event(struct rdma_event_channel *channel,
574 		      struct rdma_cm_event **event);
575 
576 /**
577  * rdma_ack_cm_event - Free a communication event.
578  * @event: Event to be released.
579  * Description:
580  *   All events which are allocated by rdma_get_cm_event must be released,
581  *   there should be a one-to-one correspondence between successful gets
582  *   and acks.
583  * See also:
584  *   rdma_get_cm_event, rdma_destroy_id
585  */
586 int rdma_ack_cm_event(struct rdma_cm_event *event);
587 
588 __be16 rdma_get_src_port(struct rdma_cm_id *id);
589 __be16 rdma_get_dst_port(struct rdma_cm_id *id);
590 
591 static inline struct sockaddr *rdma_get_local_addr(struct rdma_cm_id *id)
592 {
593 	return &id->route.addr.src_addr;
594 }
595 
596 static inline struct sockaddr *rdma_get_peer_addr(struct rdma_cm_id *id)
597 {
598 	return &id->route.addr.dst_addr;
599 }
600 
601 /**
602  * rdma_get_devices - Get list of RDMA devices currently available.
603  * @num_devices: If non-NULL, set to the number of devices returned.
604  * Description:
605  *   Return a NULL-terminated array of opened RDMA devices.  Callers can use
606  *   this routine to allocate resources on specific RDMA devices that will be
607  *   shared across multiple rdma_cm_id's.
608  * Notes:
609  *   The returned array must be released by calling rdma_free_devices.  Devices
610  *   remain opened while the librdmacm is loaded.
611  * See also:
612  *   rdma_free_devices
613  */
614 struct ibv_context **rdma_get_devices(int *num_devices);
615 
616 /**
617  * rdma_free_devices - Frees the list of devices returned by rdma_get_devices.
618  * @list: List of devices returned from rdma_get_devices.
619  * Description:
620  *   Frees the device array returned by rdma_get_devices.
621  * See also:
622  *   rdma_get_devices
623  */
624 void rdma_free_devices(struct ibv_context **list);
625 
626 /**
627  * rdma_event_str - Returns a string representation of an rdma cm event.
628  * @event: Asynchronous event.
629  * Description:
630  *   Returns a string representation of an asynchronous event.
631  * See also:
632  *   rdma_get_cm_event
633  */
634 const char *rdma_event_str(enum rdma_cm_event_type event);
635 
636 /* Option levels */
637 enum {
638 	RDMA_OPTION_ID		= 0,
639 	RDMA_OPTION_IB		= 1
640 };
641 
642 /* Option details */
643 enum {
644 	RDMA_OPTION_ID_TOS	 = 0,	/* uint8_t: RFC 2474 */
645 	RDMA_OPTION_ID_REUSEADDR = 1,   /* int: ~SO_REUSEADDR */
646 	RDMA_OPTION_ID_AFONLY	 = 2,   /* int: ~IPV6_V6ONLY */
647 	RDMA_OPTION_IB_PATH	 = 1	/* struct ibv_path_data[] */
648 };
649 
650 /**
651  * rdma_set_option - Set options for an rdma_cm_id.
652  * @id: Communication identifier to set option for.
653  * @level: Protocol level of the option to set.
654  * @optname: Name of the option to set.
655  * @optval: Reference to the option data.
656  * @optlen: The size of the %optval buffer.
657  */
658 int rdma_set_option(struct rdma_cm_id *id, int level, int optname,
659 		    void *optval, size_t optlen);
660 
661 /**
662  * rdma_migrate_id - Move an rdma_cm_id to a new event channel.
663  * @id: Communication identifier to migrate.
664  * @channel: New event channel for rdma_cm_id events.
665  */
666 int rdma_migrate_id(struct rdma_cm_id *id, struct rdma_event_channel *channel);
667 
668 /**
669  * rdma_getaddrinfo - RDMA address and route resolution service.
670  */
671 int rdma_getaddrinfo(const char *node, const char *service,
672 		     const struct rdma_addrinfo *hints,
673 		     struct rdma_addrinfo **res);
674 
675 void rdma_freeaddrinfo(struct rdma_addrinfo *res);
676 
677 #ifdef __cplusplus
678 }
679 #endif
680 
681 #endif /* RDMA_CMA_H */
682