xref: /linux/include/rdma/rdma_cm.h (revision b454cc6636d254fbf6049b73e9560aee76fb04a3)
1 /*
2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
3  * Copyright (c) 2005 Intel Corporation.  All rights reserved.
4  *
5  * This Software is licensed under one of the following licenses:
6  *
7  * 1) under the terms of the "Common Public License 1.0" a copy of which is
8  *    available from the Open Source Initiative, see
9  *    http://www.opensource.org/licenses/cpl.php.
10  *
11  * 2) under the terms of the "The BSD License" a copy of which is
12  *    available from the Open Source Initiative, see
13  *    http://www.opensource.org/licenses/bsd-license.php.
14  *
15  * 3) under the terms of the "GNU General Public License (GPL) Version 2" a
16  *    copy of which is available from the Open Source Initiative, see
17  *    http://www.opensource.org/licenses/gpl-license.php.
18  *
19  * Licensee has the right to choose one of the above licenses.
20  *
21  * Redistributions of source code must retain the above copyright
22  * notice and one of the license notices.
23  *
24  * Redistributions in binary form must reproduce both the above copyright
25  * notice, one of the license notices in the documentation
26  * and/or other materials provided with the distribution.
27  *
28  */
29 
30 #if !defined(RDMA_CM_H)
31 #define RDMA_CM_H
32 
33 #include <linux/socket.h>
34 #include <linux/in6.h>
35 #include <rdma/ib_addr.h>
36 #include <rdma/ib_sa.h>
37 
38 /*
39  * Upon receiving a device removal event, users must destroy the associated
40  * RDMA identifier and release all resources allocated with the device.
41  */
42 enum rdma_cm_event_type {
43 	RDMA_CM_EVENT_ADDR_RESOLVED,
44 	RDMA_CM_EVENT_ADDR_ERROR,
45 	RDMA_CM_EVENT_ROUTE_RESOLVED,
46 	RDMA_CM_EVENT_ROUTE_ERROR,
47 	RDMA_CM_EVENT_CONNECT_REQUEST,
48 	RDMA_CM_EVENT_CONNECT_RESPONSE,
49 	RDMA_CM_EVENT_CONNECT_ERROR,
50 	RDMA_CM_EVENT_UNREACHABLE,
51 	RDMA_CM_EVENT_REJECTED,
52 	RDMA_CM_EVENT_ESTABLISHED,
53 	RDMA_CM_EVENT_DISCONNECTED,
54 	RDMA_CM_EVENT_DEVICE_REMOVAL,
55 };
56 
57 enum rdma_port_space {
58 	RDMA_PS_SDP  = 0x0001,
59 	RDMA_PS_TCP  = 0x0106,
60 	RDMA_PS_UDP  = 0x0111,
61 	RDMA_PS_SCTP = 0x0183
62 };
63 
64 struct rdma_addr {
65 	struct sockaddr src_addr;
66 	u8		src_pad[sizeof(struct sockaddr_in6) -
67 				sizeof(struct sockaddr)];
68 	struct sockaddr dst_addr;
69 	u8		dst_pad[sizeof(struct sockaddr_in6) -
70 				sizeof(struct sockaddr)];
71 	struct rdma_dev_addr dev_addr;
72 };
73 
74 struct rdma_route {
75 	struct rdma_addr addr;
76 	struct ib_sa_path_rec *path_rec;
77 	int num_paths;
78 };
79 
80 struct rdma_conn_param {
81 	const void *private_data;
82 	u8 private_data_len;
83 	u8 responder_resources;
84 	u8 initiator_depth;
85 	u8 flow_control;
86 	u8 retry_count;		/* ignored when accepting */
87 	u8 rnr_retry_count;
88 	/* Fields below ignored if a QP is created on the rdma_cm_id. */
89 	u8 srq;
90 	u32 qp_num;
91 };
92 
93 struct rdma_ud_param {
94 	const void *private_data;
95 	u8 private_data_len;
96 	struct ib_ah_attr ah_attr;
97 	u32 qp_num;
98 	u32 qkey;
99 };
100 
101 struct rdma_cm_event {
102 	enum rdma_cm_event_type	 event;
103 	int			 status;
104 	union {
105 		struct rdma_conn_param	conn;
106 		struct rdma_ud_param	ud;
107 	} param;
108 };
109 
110 struct rdma_cm_id;
111 
112 /**
113  * rdma_cm_event_handler - Callback used to report user events.
114  *
115  * Notes: Users may not call rdma_destroy_id from this callback to destroy
116  *   the passed in id, or a corresponding listen id.  Returning a
117  *   non-zero value from the callback will destroy the passed in id.
118  */
119 typedef int (*rdma_cm_event_handler)(struct rdma_cm_id *id,
120 				     struct rdma_cm_event *event);
121 
122 struct rdma_cm_id {
123 	struct ib_device	*device;
124 	void			*context;
125 	struct ib_qp		*qp;
126 	rdma_cm_event_handler	 event_handler;
127 	struct rdma_route	 route;
128 	enum rdma_port_space	 ps;
129 	u8			 port_num;
130 };
131 
132 /**
133  * rdma_create_id - Create an RDMA identifier.
134  *
135  * @event_handler: User callback invoked to report events associated with the
136  *   returned rdma_id.
137  * @context: User specified context associated with the id.
138  * @ps: RDMA port space.
139  */
140 struct rdma_cm_id *rdma_create_id(rdma_cm_event_handler event_handler,
141 				  void *context, enum rdma_port_space ps);
142 
143 /**
144   * rdma_destroy_id - Destroys an RDMA identifier.
145   *
146   * @id: RDMA identifier.
147   *
148   * Note: calling this function has the effect of canceling in-flight
149   * asynchronous operations associated with the id.
150   */
151 void rdma_destroy_id(struct rdma_cm_id *id);
152 
153 /**
154  * rdma_bind_addr - Bind an RDMA identifier to a source address and
155  *   associated RDMA device, if needed.
156  *
157  * @id: RDMA identifier.
158  * @addr: Local address information.  Wildcard values are permitted.
159  *
160  * This associates a source address with the RDMA identifier before calling
161  * rdma_listen.  If a specific local address is given, the RDMA identifier will
162  * be bound to a local RDMA device.
163  */
164 int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr);
165 
166 /**
167  * rdma_resolve_addr - Resolve destination and optional source addresses
168  *   from IP addresses to an RDMA address.  If successful, the specified
169  *   rdma_cm_id will be bound to a local device.
170  *
171  * @id: RDMA identifier.
172  * @src_addr: Source address information.  This parameter may be NULL.
173  * @dst_addr: Destination address information.
174  * @timeout_ms: Time to wait for resolution to complete.
175  */
176 int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
177 		      struct sockaddr *dst_addr, int timeout_ms);
178 
179 /**
180  * rdma_resolve_route - Resolve the RDMA address bound to the RDMA identifier
181  *   into route information needed to establish a connection.
182  *
183  * This is called on the client side of a connection.
184  * Users must have first called rdma_resolve_addr to resolve a dst_addr
185  * into an RDMA address before calling this routine.
186  */
187 int rdma_resolve_route(struct rdma_cm_id *id, int timeout_ms);
188 
189 /**
190  * rdma_create_qp - Allocate a QP and associate it with the specified RDMA
191  * identifier.
192  *
193  * QPs allocated to an rdma_cm_id will automatically be transitioned by the CMA
194  * through their states.
195  */
196 int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
197 		   struct ib_qp_init_attr *qp_init_attr);
198 
199 /**
200  * rdma_destroy_qp - Deallocate the QP associated with the specified RDMA
201  * identifier.
202  *
203  * Users must destroy any QP associated with an RDMA identifier before
204  * destroying the RDMA ID.
205  */
206 void rdma_destroy_qp(struct rdma_cm_id *id);
207 
208 /**
209  * rdma_init_qp_attr - Initializes the QP attributes for use in transitioning
210  *   to a specified QP state.
211  * @id: Communication identifier associated with the QP attributes to
212  *   initialize.
213  * @qp_attr: On input, specifies the desired QP state.  On output, the
214  *   mandatory and desired optional attributes will be set in order to
215  *   modify the QP to the specified state.
216  * @qp_attr_mask: The QP attribute mask that may be used to transition the
217  *   QP to the specified state.
218  *
219  * Users must set the @qp_attr->qp_state to the desired QP state.  This call
220  * will set all required attributes for the given transition, along with
221  * known optional attributes.  Users may override the attributes returned from
222  * this call before calling ib_modify_qp.
223  *
224  * Users that wish to have their QP automatically transitioned through its
225  * states can associate a QP with the rdma_cm_id by calling rdma_create_qp().
226  */
227 int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
228 		       int *qp_attr_mask);
229 
230 /**
231  * rdma_connect - Initiate an active connection request.
232  * @id: Connection identifier to connect.
233  * @conn_param: Connection information used for connected QPs.
234  *
235  * Users must have resolved a route for the rdma_cm_id to connect with
236  * by having called rdma_resolve_route before calling this routine.
237  *
238  * This call will either connect to a remote QP or obtain remote QP
239  * information for unconnected rdma_cm_id's.  The actual operation is
240  * based on the rdma_cm_id's port space.
241  */
242 int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
243 
244 /**
245  * rdma_listen - This function is called by the passive side to
246  *   listen for incoming connection requests.
247  *
248  * Users must have bound the rdma_cm_id to a local address by calling
249  * rdma_bind_addr before calling this routine.
250  */
251 int rdma_listen(struct rdma_cm_id *id, int backlog);
252 
253 /**
254  * rdma_accept - Called to accept a connection request or response.
255  * @id: Connection identifier associated with the request.
256  * @conn_param: Information needed to establish the connection.  This must be
257  *   provided if accepting a connection request.  If accepting a connection
258  *   response, this parameter must be NULL.
259  *
260  * Typically, this routine is only called by the listener to accept a connection
261  * request.  It must also be called on the active side of a connection if the
262  * user is performing their own QP transitions.
263  *
264  * In the case of error, a reject message is sent to the remote side and the
265  * state of the qp associated with the id is modified to error, such that any
266  * previously posted receive buffers would be flushed.
267  */
268 int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
269 
270 /**
271  * rdma_notify - Notifies the RDMA CM of an asynchronous event that has
272  * occurred on the connection.
273  * @id: Connection identifier to transition to established.
274  * @event: Asynchronous event.
275  *
276  * This routine should be invoked by users to notify the CM of relevant
277  * communication events.  Events that should be reported to the CM and
278  * when to report them are:
279  *
280  * IB_EVENT_COMM_EST - Used when a message is received on a connected
281  *    QP before an RTU has been received.
282  */
283 int rdma_notify(struct rdma_cm_id *id, enum ib_event_type event);
284 
285 /**
286  * rdma_reject - Called to reject a connection request or response.
287  */
288 int rdma_reject(struct rdma_cm_id *id, const void *private_data,
289 		u8 private_data_len);
290 
291 /**
292  * rdma_disconnect - This function disconnects the associated QP and
293  *   transitions it into the error state.
294  */
295 int rdma_disconnect(struct rdma_cm_id *id);
296 
297 #endif /* RDMA_CM_H */
298 
299