xref: /linux/include/rdma/rdma_cm.h (revision 185000fc556372b7fb7f26516c325f212030dbd3)
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 };
62 
63 enum rdma_port_space {
64 	RDMA_PS_SDP   = 0x0001,
65 	RDMA_PS_IPOIB = 0x0002,
66 	RDMA_PS_TCP   = 0x0106,
67 	RDMA_PS_UDP   = 0x0111,
68 	RDMA_PS_SCTP  = 0x0183
69 };
70 
71 struct rdma_addr {
72 	struct sockaddr src_addr;
73 	u8		src_pad[sizeof(struct sockaddr_in6) -
74 				sizeof(struct sockaddr)];
75 	struct sockaddr dst_addr;
76 	u8		dst_pad[sizeof(struct sockaddr_in6) -
77 				sizeof(struct sockaddr)];
78 	struct rdma_dev_addr dev_addr;
79 };
80 
81 struct rdma_route {
82 	struct rdma_addr addr;
83 	struct ib_sa_path_rec *path_rec;
84 	int num_paths;
85 };
86 
87 struct rdma_conn_param {
88 	const void *private_data;
89 	u8 private_data_len;
90 	u8 responder_resources;
91 	u8 initiator_depth;
92 	u8 flow_control;
93 	u8 retry_count;		/* ignored when accepting */
94 	u8 rnr_retry_count;
95 	/* Fields below ignored if a QP is created on the rdma_cm_id. */
96 	u8 srq;
97 	u32 qp_num;
98 };
99 
100 struct rdma_ud_param {
101 	const void *private_data;
102 	u8 private_data_len;
103 	struct ib_ah_attr ah_attr;
104 	u32 qp_num;
105 	u32 qkey;
106 };
107 
108 struct rdma_cm_event {
109 	enum rdma_cm_event_type	 event;
110 	int			 status;
111 	union {
112 		struct rdma_conn_param	conn;
113 		struct rdma_ud_param	ud;
114 	} param;
115 };
116 
117 struct rdma_cm_id;
118 
119 /**
120  * rdma_cm_event_handler - Callback used to report user events.
121  *
122  * Notes: Users may not call rdma_destroy_id from this callback to destroy
123  *   the passed in id, or a corresponding listen id.  Returning a
124  *   non-zero value from the callback will destroy the passed in id.
125  */
126 typedef int (*rdma_cm_event_handler)(struct rdma_cm_id *id,
127 				     struct rdma_cm_event *event);
128 
129 struct rdma_cm_id {
130 	struct ib_device	*device;
131 	void			*context;
132 	struct ib_qp		*qp;
133 	rdma_cm_event_handler	 event_handler;
134 	struct rdma_route	 route;
135 	enum rdma_port_space	 ps;
136 	u8			 port_num;
137 };
138 
139 /**
140  * rdma_create_id - Create an RDMA identifier.
141  *
142  * @event_handler: User callback invoked to report events associated with the
143  *   returned rdma_id.
144  * @context: User specified context associated with the id.
145  * @ps: RDMA port space.
146  */
147 struct rdma_cm_id *rdma_create_id(rdma_cm_event_handler event_handler,
148 				  void *context, enum rdma_port_space ps);
149 
150 /**
151   * rdma_destroy_id - Destroys an RDMA identifier.
152   *
153   * @id: RDMA identifier.
154   *
155   * Note: calling this function has the effect of canceling in-flight
156   * asynchronous operations associated with the id.
157   */
158 void rdma_destroy_id(struct rdma_cm_id *id);
159 
160 /**
161  * rdma_bind_addr - Bind an RDMA identifier to a source address and
162  *   associated RDMA device, if needed.
163  *
164  * @id: RDMA identifier.
165  * @addr: Local address information.  Wildcard values are permitted.
166  *
167  * This associates a source address with the RDMA identifier before calling
168  * rdma_listen.  If a specific local address is given, the RDMA identifier will
169  * be bound to a local RDMA device.
170  */
171 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr);
172 
173 /**
174  * rdma_resolve_addr - Resolve destination and optional source addresses
175  *   from IP addresses to an RDMA address.  If successful, the specified
176  *   rdma_cm_id will be bound to a local device.
177  *
178  * @id: RDMA identifier.
179  * @src_addr: Source address information.  This parameter may be NULL.
180  * @dst_addr: Destination address information.
181  * @timeout_ms: Time to wait for resolution to complete.
182  */
183 int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
184 		      struct sockaddr *dst_addr, int timeout_ms);
185 
186 /**
187  * rdma_resolve_route - Resolve the RDMA address bound to the RDMA identifier
188  *   into route information needed to establish a connection.
189  *
190  * This is called on the client side of a connection.
191  * Users must have first called rdma_resolve_addr to resolve a dst_addr
192  * into an RDMA address before calling this routine.
193  */
194 int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms);
195 
196 /**
197  * rdma_create_qp - Allocate a QP and associate it with the specified RDMA
198  * identifier.
199  *
200  * QPs allocated to an rdma_cm_id will automatically be transitioned by the CMA
201  * through their states.
202  */
203 int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
204 		   struct ib_qp_init_attr *qp_init_attr);
205 
206 /**
207  * rdma_destroy_qp - Deallocate the QP associated with the specified RDMA
208  * identifier.
209  *
210  * Users must destroy any QP associated with an RDMA identifier before
211  * destroying the RDMA ID.
212  */
213 void rdma_destroy_qp(struct rdma_cm_id *id);
214 
215 /**
216  * rdma_init_qp_attr - Initializes the QP attributes for use in transitioning
217  *   to a specified QP state.
218  * @id: Communication identifier associated with the QP attributes to
219  *   initialize.
220  * @qp_attr: On input, specifies the desired QP state.  On output, the
221  *   mandatory and desired optional attributes will be set in order to
222  *   modify the QP to the specified state.
223  * @qp_attr_mask: The QP attribute mask that may be used to transition the
224  *   QP to the specified state.
225  *
226  * Users must set the @qp_attr->qp_state to the desired QP state.  This call
227  * will set all required attributes for the given transition, along with
228  * known optional attributes.  Users may override the attributes returned from
229  * this call before calling ib_modify_qp.
230  *
231  * Users that wish to have their QP automatically transitioned through its
232  * states can associate a QP with the rdma_cm_id by calling rdma_create_qp().
233  */
234 int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
235 		       int *qp_attr_mask);
236 
237 /**
238  * rdma_connect - Initiate an active connection request.
239  * @id: Connection identifier to connect.
240  * @conn_param: Connection information used for connected QPs.
241  *
242  * Users must have resolved a route for the rdma_cm_id to connect with
243  * by having called rdma_resolve_route before calling this routine.
244  *
245  * This call will either connect to a remote QP or obtain remote QP
246  * information for unconnected rdma_cm_id's.  The actual operation is
247  * based on the rdma_cm_id's port space.
248  */
249 int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
250 
251 /**
252  * rdma_listen - This function is called by the passive side to
253  *   listen for incoming connection requests.
254  *
255  * Users must have bound the rdma_cm_id to a local address by calling
256  * rdma_bind_addr before calling this routine.
257  */
258 int rdma_listen(struct rdma_cm_id *id, int backlog);
259 
260 /**
261  * rdma_accept - Called to accept a connection request or response.
262  * @id: Connection identifier associated with the request.
263  * @conn_param: Information needed to establish the connection.  This must be
264  *   provided if accepting a connection request.  If accepting a connection
265  *   response, this parameter must be NULL.
266  *
267  * Typically, this routine is only called by the listener to accept a connection
268  * request.  It must also be called on the active side of a connection if the
269  * user is performing their own QP transitions.
270  *
271  * In the case of error, a reject message is sent to the remote side and the
272  * state of the qp associated with the id is modified to error, such that any
273  * previously posted receive buffers would be flushed.
274  */
275 int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
276 
277 /**
278  * rdma_notify - Notifies the RDMA CM of an asynchronous event that has
279  * occurred on the connection.
280  * @id: Connection identifier to transition to established.
281  * @event: Asynchronous event.
282  *
283  * This routine should be invoked by users to notify the CM of relevant
284  * communication events.  Events that should be reported to the CM and
285  * when to report them are:
286  *
287  * IB_EVENT_COMM_EST - Used when a message is received on a connected
288  *    QP before an RTU has been received.
289  */
290 int rdma_notify(struct rdma_cm_id *id, enum ib_event_type event);
291 
292 /**
293  * rdma_reject - Called to reject a connection request or response.
294  */
295 int rdma_reject(struct rdma_cm_id *id, const void *private_data,
296 		u8 private_data_len);
297 
298 /**
299  * rdma_disconnect - This function disconnects the associated QP and
300  *   transitions it into the error state.
301  */
302 int rdma_disconnect(struct rdma_cm_id *id);
303 
304 /**
305  * rdma_join_multicast - Join the multicast group specified by the given
306  *   address.
307  * @id: Communication identifier associated with the request.
308  * @addr: Multicast address identifying the group to join.
309  * @context: User-defined context associated with the join request, returned
310  * to the user through the private_data pointer in multicast events.
311  */
312 int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
313 			void *context);
314 
315 /**
316  * rdma_leave_multicast - Leave the multicast group specified by the given
317  *   address.
318  */
319 void rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr);
320 
321 /**
322  * rdma_set_service_type - Set the type of service associated with a
323  *   connection identifier.
324  * @id: Communication identifier to associated with service type.
325  * @tos: Type of service.
326  *
327  * The type of service is interpretted as a differentiated service
328  * field (RFC 2474).  The service type should be specified before
329  * performing route resolution, as existing communication on the
330  * connection identifier may be unaffected.  The type of service
331  * requested may not be supported by the network to all destinations.
332  */
333 void rdma_set_service_type(struct rdma_cm_id *id, int tos);
334 
335 #endif /* RDMA_CM_H */
336