2 * Copyright (c) 2009, 2010 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #ifndef DPIF_PROVIDER_H
18 #define DPIF_PROVIDER_H 1
20 /* Provider interface to dpifs, which provide an interface to an Open vSwitch
21 * datapath. A datapath is a collection of physical or virtual ports that are
22 * exposed over OpenFlow as a single switch. Datapaths and the collections of
23 * ports that they contain may be fixed or dynamic. */
26 #include "openflow/openflow.h"
34 /* Open vSwitch datapath interface.
36 * This structure should be treated as opaque by dpif implementations. */
38 const struct dpif_class *dpif_class;
41 uint8_t netflow_engine_type;
42 uint8_t netflow_engine_id;
45 void dpif_init(struct dpif *, const struct dpif_class *, const char *name,
46 uint8_t netflow_engine_type, uint8_t netflow_engine_id);
47 void dpif_uninit(struct dpif *dpif, bool close);
49 static inline void dpif_assert_class(const struct dpif *dpif,
50 const struct dpif_class *dpif_class)
52 assert(dpif->dpif_class == dpif_class);
55 /* Datapath interface class structure, to be defined by each implementation of
56 * a datapath interface.
58 * These functions return 0 if successful or a positive errno value on failure,
59 * except where otherwise noted.
61 * These functions are expected to execute synchronously, that is, to block as
62 * necessary to obtain a result. Thus, they may not return EAGAIN or
63 * EWOULDBLOCK or EINPROGRESS. We may relax this requirement in the future if
64 * and when we encounter performance problems. */
66 /* Type of dpif in this class, e.g. "system", "netdev", etc.
68 * One of the providers should supply a "system" type, since this is
69 * the type assumed if no type is specified when opening a dpif. */
72 /* Performs periodic work needed by dpifs of this class, if any is
76 /* Arranges for poll_block() to wake up if the "run" member function needs
81 /* Starts the datapath management. This function is thought for a scenario
82 * in which the datapath and the ofproto modules are managed in different
83 * threads/processes */
86 /* Function called in the arrival of a fatal signal (e.g. SIGTERM) */
87 void (*exit_hook)(void*);
90 /* Enumerates the names of all known created datapaths, if possible, into
91 * 'all_dps'. The caller has already initialized 'all_dps' and other dpif
92 * classes might already have added names to it.
94 * This is used by the vswitch at startup, so that it can delete any
95 * datapaths that are not configured.
97 * Some kinds of datapaths might not be practically enumerable, in which
98 * case this function may be a null pointer. */
99 int (*enumerate)(struct svec *all_dps);
101 /* Attempts to open an existing dpif called 'name', if 'create' is false,
102 * or to open an existing dpif or create a new one, if 'create' is true.
103 * 'type' corresponds to the 'type' field used in the dpif_class
106 * If successful, stores a pointer to the new dpif in '*dpifp'. On failure
107 * there are no requirements on what is stored in '*dpifp'. */
108 int (*open)(const char *name, const char *type, bool create,
109 struct dpif **dpifp);
111 /* Closes 'dpif' and frees associated memory. */
112 void (*close)(struct dpif *dpif);
114 /* Enumerates all names that may be used to open 'dpif' into 'all_names'.
115 * The Linux datapath, for example, supports opening a datapath both by
116 * number, e.g. "dp0", and by the name of the datapath's local port. For
117 * some datapaths, this might be an infinite set (e.g. in a file name,
118 * slashes may be duplicated any number of times), in which case only the
119 * names most likely to be used should be enumerated.
121 * The caller has already initialized 'all_names' and might already have
122 * added some names to it. This function should not disturb any existing
123 * names in 'all_names'.
125 * If a datapath class does not support multiple names for a datapath, this
126 * function may be a null pointer.
128 * This is used by the vswitch at startup, */
129 int (*get_all_names)(const struct dpif *dpif, struct svec *all_names);
131 /* Attempts to destroy the dpif underlying 'dpif'.
133 * If successful, 'dpif' will not be used again except as an argument for
134 * the 'close' member function. */
135 int (*destroy)(struct dpif *dpif);
137 /* Retrieves statistics for 'dpif' into 'stats'. */
138 int (*get_stats)(const struct dpif *dpif, struct odp_stats *stats);
140 /* Retrieves 'dpif''s current treatment of IP fragments into '*drop_frags':
141 * true indicates that fragments are dropped, false indicates that
142 * fragments are treated in the same way as other IP packets (except that
143 * the L4 header cannot be read). */
144 int (*get_drop_frags)(const struct dpif *dpif, bool *drop_frags);
146 /* Changes 'dpif''s treatment of IP fragments to 'drop_frags', whose
147 * meaning is the same as for the get_drop_frags member function. */
148 int (*set_drop_frags)(struct dpif *dpif, bool drop_frags);
150 /* Creates a new port in 'dpif' connected to network device 'devname'.
151 * 'flags' is a set of ODP_PORT_* flags. If successful, sets '*port_no'
152 * to the new port's port number. */
153 int (*port_add)(struct dpif *dpif, const char *devname, uint16_t flags,
156 /* Removes port numbered 'port_no' from 'dpif'. */
157 int (*port_del)(struct dpif *dpif, uint16_t port_no);
159 /* Queries 'dpif' for a port with the given 'port_no' or 'devname'. Stores
160 * information about the port into '*port' if successful. */
161 int (*port_query_by_number)(const struct dpif *dpif, uint16_t port_no,
162 struct odp_port *port);
163 int (*port_query_by_name)(const struct dpif *dpif, const char *devname,
164 struct odp_port *port);
166 /* Stores in 'ports' information about up to 'n' ports attached to 'dpif',
167 * in no particular order. Returns the number of ports attached to 'dpif'
168 * (not the number stored), if successful, otherwise a negative errno
170 int (*port_list)(const struct dpif *dpif, struct odp_port *ports, int n);
172 /* Polls for changes in the set of ports in 'dpif'. If the set of ports in
173 * 'dpif' has changed, then this function should do one of the
176 * - Preferably: store the name of the device that was added to or deleted
177 * from 'dpif' in '*devnamep' and return 0. The caller is responsible
178 * for freeing '*devnamep' (with free()) when it no longer needs it.
180 * - Alternatively: return ENOBUFS, without indicating the device that was
183 * Occasional 'false positives', in which the function returns 0 while
184 * indicating a device that was not actually added or deleted or returns
185 * ENOBUFS without any change, are acceptable.
187 * If the set of ports in 'dpif' has not changed, returns EAGAIN. May also
188 * return other positive errno values to indicate that something has gone
190 int (*port_poll)(const struct dpif *dpif, char **devnamep);
192 /* Arranges for the poll loop to wake up when 'port_poll' will return a
193 * value other than EAGAIN. */
194 void (*port_poll_wait)(const struct dpif *dpif);
196 /* Stores in 'ports' the port numbers of up to 'n' ports that belong to
197 * 'group' in 'dpif'. Returns the number of ports in 'group' (not the
198 * number stored), if successful, otherwise a negative errno value. */
199 int (*port_group_get)(const struct dpif *dpif, int group,
200 uint16_t ports[], int n);
202 /* Changes port group 'group' in 'dpif' to consist of the 'n' ports whose
203 * numbers are given in 'ports'.
205 * Use the get_stats member function to obtain the number of supported port
207 int (*port_group_set)(struct dpif *dpif, int group,
208 const uint16_t ports[], int n);
210 /* For each flow 'flow' in the 'n' flows in 'flows':
212 * - If a flow matching 'flow->key' exists in 'dpif':
214 * Stores 0 into 'flow->stats.error' and stores statistics for the flow
215 * into 'flow->stats'.
217 * If 'flow->n_actions' is zero, then 'flow->actions' is ignored. If
218 * 'flow->n_actions' is nonzero, then 'flow->actions' should point to
219 * an array of the specified number of actions. At most that many of
220 * the flow's actions will be copied into that array.
221 * 'flow->n_actions' will be updated to the number of actions actually
222 * present in the flow, which may be greater than the number stored if
223 * the flow has more actions than space available in the array.
225 * - Flow-specific errors are indicated by a positive errno value in
226 * 'flow->stats.error'. In particular, ENOENT indicates that no flow
227 * matching 'flow->key' exists in 'dpif'. When an error value is stored,
228 * the contents of 'flow->key' are preserved but other members of 'flow'
229 * should be treated as indeterminate.
231 * Returns 0 if all 'n' flows in 'flows' were updated (whether they were
232 * individually successful or not is indicated by 'flow->stats.error',
233 * however). Returns a positive errno value if an error that prevented
234 * this update occurred, in which the caller must not depend on any
235 * elements in 'flows' being updated or not updated.
237 int (*flow_get)(const struct dpif *dpif, struct odp_flow flows[], int n);
239 /* Adds or modifies a flow in 'dpif' as specified in 'put':
241 * - If the flow specified in 'put->flow' does not exist in 'dpif', then
242 * behavior depends on whether ODPPF_CREATE is specified in 'put->flags':
243 * if it is, the flow will be added, otherwise the operation will fail
246 * - Otherwise, the flow specified in 'put->flow' does exist in 'dpif'.
247 * Behavior in this case depends on whether ODPPF_MODIFY is specified in
248 * 'put->flags': if it is, the flow's actions will be updated, otherwise
249 * the operation will fail with EEXIST. If the flow's actions are
250 * updated, then its statistics will be zeroed if ODPPF_ZERO_STATS is set
251 * in 'put->flags', left as-is otherwise.
253 int (*flow_put)(struct dpif *dpif, struct odp_flow_put *put);
255 /* Deletes a flow matching 'flow->key' from 'dpif' or returns ENOENT if
256 * 'dpif' does not contain such a flow.
258 * If successful, updates 'flow->stats', 'flow->n_actions', and
259 * 'flow->actions' as described in more detail under the flow_get member
261 int (*flow_del)(struct dpif *dpif, struct odp_flow *flow);
263 /* Deletes all flows from 'dpif' and clears all of its queues of received
265 int (*flow_flush)(struct dpif *dpif);
267 /* Stores up to 'n' flows in 'dpif' into 'flows', updating their statistics
268 * and actions as described under the flow_get member function. If
269 * successful, returns the number of flows actually present in 'dpif',
270 * which might be greater than the number stored (if 'dpif' has more than
271 * 'n' flows). On failure, returns a negative errno value. */
272 int (*flow_list)(const struct dpif *dpif, struct odp_flow flows[], int n);
274 /* Performs the 'n_actions' actions in 'actions' on the Ethernet frame
275 * specified in 'packet'.
277 * Pretends that the frame was originally received on the port numbered
278 * 'in_port'. This affects only ODPAT_OUTPUT_GROUP actions, which will not
279 * send a packet out their input port. Specify the number of an unused
280 * port (e.g. UINT16_MAX is currently always unused) to avoid this
282 int (*execute)(struct dpif *dpif, uint16_t in_port,
283 const union odp_action actions[], int n_actions,
284 const struct ofpbuf *packet);
286 /* Retrieves 'dpif''s "listen mask" into '*listen_mask'. Each ODPL_* bit
287 * set in '*listen_mask' indicates the 'dpif' will receive messages of the
288 * corresponding type when it calls the recv member function. */
289 int (*recv_get_mask)(const struct dpif *dpif, int *listen_mask);
291 /* Sets 'dpif''s "listen mask" to 'listen_mask'. Each ODPL_* bit set in
292 * 'listen_mask' indicates the 'dpif' will receive messages of the
293 * corresponding type when it calls the recv member function. */
294 int (*recv_set_mask)(struct dpif *dpif, int listen_mask);
296 /* Retrieves 'dpif''s sFlow sampling probability into '*probability'.
297 * Return value is 0 or a positive errno value. EOPNOTSUPP indicates that
298 * the datapath does not support sFlow, as does a null pointer.
300 * '*probability' is expressed as the number of packets out of UINT_MAX to
301 * sample, e.g. probability/UINT_MAX is the probability of sampling a given
303 int (*get_sflow_probability)(const struct dpif *dpif,
304 uint32_t *probability);
306 /* Sets 'dpif''s sFlow sampling probability to 'probability'. Return value
307 * is 0 or a positive errno value. EOPNOTSUPP indicates that the datapath
308 * does not support sFlow, as does a null pointer.
310 * 'probability' is expressed as the number of packets out of UINT_MAX to
311 * sample, e.g. probability/UINT_MAX is the probability of sampling a given
313 int (*set_sflow_probability)(struct dpif *dpif, uint32_t probability);
315 /* Translates OpenFlow queue ID 'queue_id' (in host byte order) into a
316 * priority value for use in the ODPAT_SET_PRIORITY action in
318 int (*queue_to_priority)(const struct dpif *dpif, uint32_t queue_id,
321 /* Attempts to receive a message from 'dpif'. If successful, stores the
322 * message into '*packetp'. The message, if one is received, must begin
323 * with 'struct odp_msg' as a header, and must have at least
324 * DPIF_RECV_MSG_PADDING bytes of headroom (allocated using
325 * e.g. ofpbuf_reserve()). Only messages of the types selected with the
326 * set_listen_mask member function should be received.
328 * This function must not block. If no message is ready to be received
329 * when it is called, it should return EAGAIN without blocking. */
330 int (*recv)(struct dpif *dpif, struct ofpbuf **packetp);
332 /* Arranges for the poll loop to wake up when 'dpif' has a message queued
333 * to be received with the recv member function. */
334 void (*recv_wait)(struct dpif *dpif);
337 extern const struct dpif_class dpif_linux_class;
338 extern const struct dpif_class dpif_netdev_class;
344 #endif /* dpif-provider.h */