xref: /openbmc/linux/include/rdma/ib_cm.h (revision 6417f031)
1 /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
2 /*
3  * Copyright (c) 2004, 2005 Intel Corporation.  All rights reserved.
4  * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
5  * Copyright (c) 2004 Voltaire Corporation.  All rights reserved.
6  * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
7  * Copyright (c) 2019, Mellanox Technologies inc.  All rights reserved.
8  */
9 
10 #ifndef IB_CM_H
11 #define IB_CM_H
12 
13 #include <rdma/ib_mad.h>
14 #include <rdma/ib_sa.h>
15 #include <rdma/rdma_cm.h>
16 
17 enum ib_cm_state {
18 	IB_CM_IDLE,
19 	IB_CM_LISTEN,
20 	IB_CM_REQ_SENT,
21 	IB_CM_REQ_RCVD,
22 	IB_CM_MRA_REQ_SENT,
23 	IB_CM_MRA_REQ_RCVD,
24 	IB_CM_REP_SENT,
25 	IB_CM_REP_RCVD,
26 	IB_CM_MRA_REP_SENT,
27 	IB_CM_MRA_REP_RCVD,
28 	IB_CM_ESTABLISHED,
29 	IB_CM_DREQ_SENT,
30 	IB_CM_DREQ_RCVD,
31 	IB_CM_TIMEWAIT,
32 	IB_CM_SIDR_REQ_SENT,
33 	IB_CM_SIDR_REQ_RCVD
34 };
35 
36 enum ib_cm_lap_state {
37 	IB_CM_LAP_UNINIT,
38 	IB_CM_LAP_IDLE,
39 	IB_CM_LAP_SENT,
40 	IB_CM_LAP_RCVD,
41 	IB_CM_MRA_LAP_SENT,
42 	IB_CM_MRA_LAP_RCVD,
43 };
44 
45 enum ib_cm_event_type {
46 	IB_CM_REQ_ERROR,
47 	IB_CM_REQ_RECEIVED,
48 	IB_CM_REP_ERROR,
49 	IB_CM_REP_RECEIVED,
50 	IB_CM_RTU_RECEIVED,
51 	IB_CM_USER_ESTABLISHED,
52 	IB_CM_DREQ_ERROR,
53 	IB_CM_DREQ_RECEIVED,
54 	IB_CM_DREP_RECEIVED,
55 	IB_CM_TIMEWAIT_EXIT,
56 	IB_CM_MRA_RECEIVED,
57 	IB_CM_REJ_RECEIVED,
58 	IB_CM_LAP_ERROR,
59 	IB_CM_LAP_RECEIVED,
60 	IB_CM_APR_RECEIVED,
61 	IB_CM_SIDR_REQ_ERROR,
62 	IB_CM_SIDR_REQ_RECEIVED,
63 	IB_CM_SIDR_REP_RECEIVED
64 };
65 
66 enum ib_cm_data_size {
67 	IB_CM_REQ_PRIVATE_DATA_SIZE	 = 92,
68 	IB_CM_MRA_PRIVATE_DATA_SIZE	 = 222,
69 	IB_CM_REJ_PRIVATE_DATA_SIZE	 = 148,
70 	IB_CM_REP_PRIVATE_DATA_SIZE	 = 196,
71 	IB_CM_RTU_PRIVATE_DATA_SIZE	 = 224,
72 	IB_CM_DREQ_PRIVATE_DATA_SIZE	 = 220,
73 	IB_CM_DREP_PRIVATE_DATA_SIZE	 = 224,
74 	IB_CM_REJ_ARI_LENGTH		 = 72,
75 	IB_CM_LAP_PRIVATE_DATA_SIZE	 = 168,
76 	IB_CM_APR_PRIVATE_DATA_SIZE	 = 148,
77 	IB_CM_APR_INFO_LENGTH		 = 72,
78 	IB_CM_SIDR_REQ_PRIVATE_DATA_SIZE = 216,
79 	IB_CM_SIDR_REP_PRIVATE_DATA_SIZE = 136,
80 	IB_CM_SIDR_REP_INFO_LENGTH	 = 72,
81 };
82 
83 struct ib_cm_id;
84 
85 struct ib_cm_req_event_param {
86 	struct ib_cm_id		*listen_id;
87 
88 	/* P_Key that was used by the GMP's BTH header */
89 	u16			bth_pkey;
90 
91 	u8			port;
92 
93 	struct sa_path_rec	*primary_path;
94 	struct sa_path_rec	*alternate_path;
95 
96 	/*
97 	 * SGID attribute of the primary path. Currently only
98 	 * useful for RoCE. Alternate path GID attributes
99 	 * are not yet supported.
100 	 */
101 	const struct ib_gid_attr *ppath_sgid_attr;
102 
103 	__be64			remote_ca_guid;
104 	u32			remote_qkey;
105 	u32			remote_qpn;
106 	enum ib_qp_type		qp_type;
107 
108 	u32			starting_psn;
109 	u8			responder_resources;
110 	u8			initiator_depth;
111 	unsigned int		local_cm_response_timeout:5;
112 	unsigned int		flow_control:1;
113 	unsigned int		remote_cm_response_timeout:5;
114 	unsigned int		retry_count:3;
115 	unsigned int		rnr_retry_count:3;
116 	unsigned int		srq:1;
117 	struct rdma_ucm_ece	ece;
118 };
119 
120 struct ib_cm_rep_event_param {
121 	__be64			remote_ca_guid;
122 	u32			remote_qkey;
123 	u32			remote_qpn;
124 	u32			starting_psn;
125 	u8			responder_resources;
126 	u8			initiator_depth;
127 	unsigned int		target_ack_delay:5;
128 	unsigned int		failover_accepted:2;
129 	unsigned int		flow_control:1;
130 	unsigned int		rnr_retry_count:3;
131 	unsigned int		srq:1;
132 	struct rdma_ucm_ece	ece;
133 };
134 
135 enum ib_cm_rej_reason {
136 	IB_CM_REJ_NO_QP				= 1,
137 	IB_CM_REJ_NO_EEC			= 2,
138 	IB_CM_REJ_NO_RESOURCES			= 3,
139 	IB_CM_REJ_TIMEOUT			= 4,
140 	IB_CM_REJ_UNSUPPORTED			= 5,
141 	IB_CM_REJ_INVALID_COMM_ID		= 6,
142 	IB_CM_REJ_INVALID_COMM_INSTANCE		= 7,
143 	IB_CM_REJ_INVALID_SERVICE_ID		= 8,
144 	IB_CM_REJ_INVALID_TRANSPORT_TYPE	= 9,
145 	IB_CM_REJ_STALE_CONN			= 10,
146 	IB_CM_REJ_RDC_NOT_EXIST			= 11,
147 	IB_CM_REJ_INVALID_GID			= 12,
148 	IB_CM_REJ_INVALID_LID			= 13,
149 	IB_CM_REJ_INVALID_SL			= 14,
150 	IB_CM_REJ_INVALID_TRAFFIC_CLASS		= 15,
151 	IB_CM_REJ_INVALID_HOP_LIMIT		= 16,
152 	IB_CM_REJ_INVALID_PACKET_RATE		= 17,
153 	IB_CM_REJ_INVALID_ALT_GID		= 18,
154 	IB_CM_REJ_INVALID_ALT_LID		= 19,
155 	IB_CM_REJ_INVALID_ALT_SL		= 20,
156 	IB_CM_REJ_INVALID_ALT_TRAFFIC_CLASS	= 21,
157 	IB_CM_REJ_INVALID_ALT_HOP_LIMIT		= 22,
158 	IB_CM_REJ_INVALID_ALT_PACKET_RATE	= 23,
159 	IB_CM_REJ_PORT_CM_REDIRECT		= 24,
160 	IB_CM_REJ_PORT_REDIRECT			= 25,
161 	IB_CM_REJ_INVALID_MTU			= 26,
162 	IB_CM_REJ_INSUFFICIENT_RESP_RESOURCES	= 27,
163 	IB_CM_REJ_CONSUMER_DEFINED		= 28,
164 	IB_CM_REJ_INVALID_RNR_RETRY		= 29,
165 	IB_CM_REJ_DUPLICATE_LOCAL_COMM_ID	= 30,
166 	IB_CM_REJ_INVALID_CLASS_VERSION		= 31,
167 	IB_CM_REJ_INVALID_FLOW_LABEL		= 32,
168 	IB_CM_REJ_INVALID_ALT_FLOW_LABEL	= 33,
169 	IB_CM_REJ_VENDOR_OPTION_NOT_SUPPORTED	= 35,
170 };
171 
172 struct ib_cm_rej_event_param {
173 	enum ib_cm_rej_reason	reason;
174 	void			*ari;
175 	u8			ari_length;
176 };
177 
178 struct ib_cm_mra_event_param {
179 	u8	service_timeout;
180 };
181 
182 struct ib_cm_lap_event_param {
183 	struct sa_path_rec	*alternate_path;
184 };
185 
186 enum ib_cm_apr_status {
187 	IB_CM_APR_SUCCESS,
188 	IB_CM_APR_INVALID_COMM_ID,
189 	IB_CM_APR_UNSUPPORTED,
190 	IB_CM_APR_REJECT,
191 	IB_CM_APR_REDIRECT,
192 	IB_CM_APR_IS_CURRENT,
193 	IB_CM_APR_INVALID_QPN_EECN,
194 	IB_CM_APR_INVALID_LID,
195 	IB_CM_APR_INVALID_GID,
196 	IB_CM_APR_INVALID_FLOW_LABEL,
197 	IB_CM_APR_INVALID_TCLASS,
198 	IB_CM_APR_INVALID_HOP_LIMIT,
199 	IB_CM_APR_INVALID_PACKET_RATE,
200 	IB_CM_APR_INVALID_SL
201 };
202 
203 struct ib_cm_apr_event_param {
204 	enum ib_cm_apr_status	ap_status;
205 	void			*apr_info;
206 	u8			info_len;
207 };
208 
209 struct ib_cm_sidr_req_event_param {
210 	struct ib_cm_id		*listen_id;
211 	__be64			service_id;
212 
213 	/*
214 	 * SGID attribute of the request. Currently only
215 	 * useful for RoCE.
216 	 */
217 	const struct ib_gid_attr *sgid_attr;
218 	/* P_Key that was used by the GMP's BTH header */
219 	u16			bth_pkey;
220 	u8			port;
221 	u16			pkey;
222 };
223 
224 enum ib_cm_sidr_status {
225 	IB_SIDR_SUCCESS,
226 	IB_SIDR_UNSUPPORTED,
227 	IB_SIDR_REJECT,
228 	IB_SIDR_NO_QP,
229 	IB_SIDR_REDIRECT,
230 	IB_SIDR_UNSUPPORTED_VERSION
231 };
232 
233 struct ib_cm_sidr_rep_event_param {
234 	enum ib_cm_sidr_status	status;
235 	u32			qkey;
236 	u32			qpn;
237 	void			*info;
238 	const struct ib_gid_attr *sgid_attr;
239 	u8			info_len;
240 };
241 
242 struct ib_cm_event {
243 	enum ib_cm_event_type	event;
244 	union {
245 		struct ib_cm_req_event_param	req_rcvd;
246 		struct ib_cm_rep_event_param	rep_rcvd;
247 		/* No data for RTU received events. */
248 		struct ib_cm_rej_event_param	rej_rcvd;
249 		struct ib_cm_mra_event_param	mra_rcvd;
250 		struct ib_cm_lap_event_param	lap_rcvd;
251 		struct ib_cm_apr_event_param	apr_rcvd;
252 		/* No data for DREQ/DREP received events. */
253 		struct ib_cm_sidr_req_event_param sidr_req_rcvd;
254 		struct ib_cm_sidr_rep_event_param sidr_rep_rcvd;
255 		enum ib_wc_status		send_status;
256 	} param;
257 
258 	void			*private_data;
259 };
260 
261 #define CM_REQ_ATTR_ID		cpu_to_be16(0x0010)
262 #define CM_MRA_ATTR_ID		cpu_to_be16(0x0011)
263 #define CM_REJ_ATTR_ID		cpu_to_be16(0x0012)
264 #define CM_REP_ATTR_ID		cpu_to_be16(0x0013)
265 #define CM_RTU_ATTR_ID		cpu_to_be16(0x0014)
266 #define CM_DREQ_ATTR_ID		cpu_to_be16(0x0015)
267 #define CM_DREP_ATTR_ID		cpu_to_be16(0x0016)
268 #define CM_SIDR_REQ_ATTR_ID	cpu_to_be16(0x0017)
269 #define CM_SIDR_REP_ATTR_ID	cpu_to_be16(0x0018)
270 #define CM_LAP_ATTR_ID		cpu_to_be16(0x0019)
271 #define CM_APR_ATTR_ID		cpu_to_be16(0x001A)
272 
273 /**
274  * ib_cm_handler - User-defined callback to process communication events.
275  * @cm_id: Communication identifier associated with the reported event.
276  * @event: Information about the communication event.
277  *
278  * IB_CM_REQ_RECEIVED and IB_CM_SIDR_REQ_RECEIVED communication events
279  * generated as a result of listen requests result in the allocation of a
280  * new @cm_id.  The new @cm_id is returned to the user through this callback.
281  * Clients are responsible for destroying the new @cm_id.  For peer-to-peer
282  * IB_CM_REQ_RECEIVED and all other events, the returned @cm_id corresponds
283  * to a user's existing communication identifier.
284  *
285  * Users may not call ib_destroy_cm_id while in the context of this callback;
286  * however, returning a non-zero value instructs the communication manager to
287  * destroy the @cm_id after the callback completes.
288  */
289 typedef int (*ib_cm_handler)(struct ib_cm_id *cm_id,
290 			     const struct ib_cm_event *event);
291 
292 struct ib_cm_id {
293 	ib_cm_handler		cm_handler;
294 	void			*context;
295 	struct ib_device	*device;
296 	__be64			service_id;
297 	__be64			service_mask;
298 	enum ib_cm_state	state;		/* internal CM/debug use */
299 	enum ib_cm_lap_state	lap_state;	/* internal CM/debug use */
300 	__be32			local_id;
301 	__be32			remote_id;
302 	u32			remote_cm_qpn;  /* 1 unless redirected */
303 };
304 
305 /**
306  * ib_create_cm_id - Allocate a communication identifier.
307  * @device: Device associated with the cm_id.  All related communication will
308  * be associated with the specified device.
309  * @cm_handler: Callback invoked to notify the user of CM events.
310  * @context: User specified context associated with the communication
311  *   identifier.
312  *
313  * Communication identifiers are used to track connection states, service
314  * ID resolution requests, and listen requests.
315  */
316 struct ib_cm_id *ib_create_cm_id(struct ib_device *device,
317 				 ib_cm_handler cm_handler,
318 				 void *context);
319 
320 /**
321  * ib_destroy_cm_id - Destroy a connection identifier.
322  * @cm_id: Connection identifier to destroy.
323  *
324  * This call blocks until the connection identifier is destroyed.
325  */
326 void ib_destroy_cm_id(struct ib_cm_id *cm_id);
327 
328 #define IB_SERVICE_ID_AGN_MASK	cpu_to_be64(0xFF00000000000000ULL)
329 #define IB_CM_ASSIGN_SERVICE_ID	cpu_to_be64(0x0200000000000000ULL)
330 #define IB_CMA_SERVICE_ID	cpu_to_be64(0x0000000001000000ULL)
331 #define IB_CMA_SERVICE_ID_MASK	cpu_to_be64(0xFFFFFFFFFF000000ULL)
332 #define IB_SDP_SERVICE_ID	cpu_to_be64(0x0000000000010000ULL)
333 #define IB_SDP_SERVICE_ID_MASK	cpu_to_be64(0xFFFFFFFFFFFF0000ULL)
334 
335 /**
336  * ib_cm_listen - Initiates listening on the specified service ID for
337  *   connection and service ID resolution requests.
338  * @cm_id: Connection identifier associated with the listen request.
339  * @service_id: Service identifier matched against incoming connection
340  *   and service ID resolution requests.  The service ID should be specified
341  *   network-byte order.  If set to IB_CM_ASSIGN_SERVICE_ID, the CM will
342  *   assign a service ID to the caller.
343  * @service_mask: Mask applied to service ID used to listen across a
344  *   range of service IDs.  If set to 0, the service ID is matched
345  *   exactly.  This parameter is ignored if %service_id is set to
346  *   IB_CM_ASSIGN_SERVICE_ID.
347  */
348 int ib_cm_listen(struct ib_cm_id *cm_id, __be64 service_id,
349 		 __be64 service_mask);
350 
351 struct ib_cm_id *ib_cm_insert_listen(struct ib_device *device,
352 				     ib_cm_handler cm_handler,
353 				     __be64 service_id);
354 
355 struct ib_cm_req_param {
356 	struct sa_path_rec	*primary_path;
357 	struct sa_path_rec	*alternate_path;
358 	const struct ib_gid_attr *ppath_sgid_attr;
359 	__be64			service_id;
360 	u32			qp_num;
361 	enum ib_qp_type		qp_type;
362 	u32			starting_psn;
363 	const void		*private_data;
364 	u8			private_data_len;
365 	u8			responder_resources;
366 	u8			initiator_depth;
367 	u8			remote_cm_response_timeout;
368 	u8			flow_control;
369 	u8			local_cm_response_timeout;
370 	u8			retry_count;
371 	u8			rnr_retry_count;
372 	u8			max_cm_retries;
373 	u8			srq;
374 	struct rdma_ucm_ece	ece;
375 };
376 
377 /**
378  * ib_send_cm_req - Sends a connection request to the remote node.
379  * @cm_id: Connection identifier that will be associated with the
380  *   connection request.
381  * @param: Connection request information needed to establish the
382  *   connection.
383  */
384 int ib_send_cm_req(struct ib_cm_id *cm_id,
385 		   struct ib_cm_req_param *param);
386 
387 struct ib_cm_rep_param {
388 	u32		qp_num;
389 	u32		starting_psn;
390 	const void	*private_data;
391 	u8		private_data_len;
392 	u8		responder_resources;
393 	u8		initiator_depth;
394 	u8		failover_accepted;
395 	u8		flow_control;
396 	u8		rnr_retry_count;
397 	u8		srq;
398 	struct rdma_ucm_ece ece;
399 };
400 
401 /**
402  * ib_send_cm_rep - Sends a connection reply in response to a connection
403  *   request.
404  * @cm_id: Connection identifier that will be associated with the
405  *   connection request.
406  * @param: Connection reply information needed to establish the
407  *   connection.
408  */
409 int ib_send_cm_rep(struct ib_cm_id *cm_id,
410 		   struct ib_cm_rep_param *param);
411 
412 /**
413  * ib_send_cm_rtu - Sends a connection ready to use message in response
414  *   to a connection reply message.
415  * @cm_id: Connection identifier associated with the connection request.
416  * @private_data: Optional user-defined private data sent with the
417  *   ready to use message.
418  * @private_data_len: Size of the private data buffer, in bytes.
419  */
420 int ib_send_cm_rtu(struct ib_cm_id *cm_id,
421 		   const void *private_data,
422 		   u8 private_data_len);
423 
424 /**
425  * ib_send_cm_dreq - Sends a disconnection request for an existing
426  *   connection.
427  * @cm_id: Connection identifier associated with the connection being
428  *   released.
429  * @private_data: Optional user-defined private data sent with the
430  *   disconnection request message.
431  * @private_data_len: Size of the private data buffer, in bytes.
432  */
433 int ib_send_cm_dreq(struct ib_cm_id *cm_id,
434 		    const void *private_data,
435 		    u8 private_data_len);
436 
437 /**
438  * ib_send_cm_drep - Sends a disconnection reply to a disconnection request.
439  * @cm_id: Connection identifier associated with the connection being
440  *   released.
441  * @private_data: Optional user-defined private data sent with the
442  *   disconnection reply message.
443  * @private_data_len: Size of the private data buffer, in bytes.
444  *
445  * If the cm_id is in the correct state, the CM will transition the connection
446  * to the timewait state, even if an error occurs sending the DREP message.
447  */
448 int ib_send_cm_drep(struct ib_cm_id *cm_id,
449 		    const void *private_data,
450 		    u8 private_data_len);
451 
452 /**
453  * ib_cm_notify - Notifies the CM of an event reported to the consumer.
454  * @cm_id: Connection identifier to transition to established.
455  * @event: Type of event.
456  *
457  * This routine should be invoked by users to notify the CM of relevant
458  * communication events.  Events that should be reported to the CM and
459  * when to report them are:
460  *
461  * IB_EVENT_COMM_EST - Used when a message is received on a connected
462  *    QP before an RTU has been received.
463  * IB_EVENT_PATH_MIG - Notifies the CM that the connection has failed over
464  *   to the alternate path.
465  */
466 int ib_cm_notify(struct ib_cm_id *cm_id, enum ib_event_type event);
467 
468 /**
469  * ib_send_cm_rej - Sends a connection rejection message to the
470  *   remote node.
471  * @cm_id: Connection identifier associated with the connection being
472  *   rejected.
473  * @reason: Reason for the connection request rejection.
474  * @ari: Optional additional rejection information.
475  * @ari_length: Size of the additional rejection information, in bytes.
476  * @private_data: Optional user-defined private data sent with the
477  *   rejection message.
478  * @private_data_len: Size of the private data buffer, in bytes.
479  */
480 int ib_send_cm_rej(struct ib_cm_id *cm_id,
481 		   enum ib_cm_rej_reason reason,
482 		   void *ari,
483 		   u8 ari_length,
484 		   const void *private_data,
485 		   u8 private_data_len);
486 
487 #define IB_CM_MRA_FLAG_DELAY 0x80  /* Send MRA only after a duplicate msg */
488 
489 /**
490  * ib_send_cm_mra - Sends a message receipt acknowledgement to a connection
491  *   message.
492  * @cm_id: Connection identifier associated with the connection message.
493  * @service_timeout: The lower 5-bits specify the maximum time required for
494  *   the sender to reply to the connection message.  The upper 3-bits
495  *   specify additional control flags.
496  * @private_data: Optional user-defined private data sent with the
497  *   message receipt acknowledgement.
498  * @private_data_len: Size of the private data buffer, in bytes.
499  */
500 int ib_send_cm_mra(struct ib_cm_id *cm_id,
501 		   u8 service_timeout,
502 		   const void *private_data,
503 		   u8 private_data_len);
504 
505 /**
506  * ib_cm_init_qp_attr - Initializes the QP attributes for use in transitioning
507  *   to a specified QP state.
508  * @cm_id: Communication identifier associated with the QP attributes to
509  *   initialize.
510  * @qp_attr: On input, specifies the desired QP state.  On output, the
511  *   mandatory and desired optional attributes will be set in order to
512  *   modify the QP to the specified state.
513  * @qp_attr_mask: The QP attribute mask that may be used to transition the
514  *   QP to the specified state.
515  *
516  * Users must set the @qp_attr->qp_state to the desired QP state.  This call
517  * will set all required attributes for the given transition, along with
518  * known optional attributes.  Users may override the attributes returned from
519  * this call before calling ib_modify_qp.
520  */
521 int ib_cm_init_qp_attr(struct ib_cm_id *cm_id,
522 		       struct ib_qp_attr *qp_attr,
523 		       int *qp_attr_mask);
524 
525 struct ib_cm_sidr_req_param {
526 	struct sa_path_rec	*path;
527 	const struct ib_gid_attr *sgid_attr;
528 	__be64			service_id;
529 	unsigned long		timeout_ms;
530 	const void		*private_data;
531 	u8			private_data_len;
532 	u8			max_cm_retries;
533 };
534 
535 /**
536  * ib_send_cm_sidr_req - Sends a service ID resolution request to the
537  *   remote node.
538  * @cm_id: Communication identifier that will be associated with the
539  *   service ID resolution request.
540  * @param: Service ID resolution request information.
541  */
542 int ib_send_cm_sidr_req(struct ib_cm_id *cm_id,
543 			struct ib_cm_sidr_req_param *param);
544 
545 struct ib_cm_sidr_rep_param {
546 	u32			qp_num;
547 	u32			qkey;
548 	enum ib_cm_sidr_status	status;
549 	const void		*info;
550 	u8			info_length;
551 	const void		*private_data;
552 	u8			private_data_len;
553 	struct rdma_ucm_ece	ece;
554 };
555 
556 /**
557  * ib_send_cm_sidr_rep - Sends a service ID resolution reply to the
558  *   remote node.
559  * @cm_id: Communication identifier associated with the received service ID
560  *   resolution request.
561  * @param: Service ID resolution reply information.
562  */
563 int ib_send_cm_sidr_rep(struct ib_cm_id *cm_id,
564 			struct ib_cm_sidr_rep_param *param);
565 
566 /**
567  * ibcm_reject_msg - return a pointer to a reject message string.
568  * @reason: Value returned in the REJECT event status field.
569  */
570 const char *__attribute_const__ ibcm_reject_msg(int reason);
571 
572 #endif /* IB_CM_H */
573