2 * Copyright (c) 2009, 2010, 2011 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
80 /* Enumerates the names of all known created datapaths, if possible, into
81 * 'all_dps'. The caller has already initialized 'all_dps' and other dpif
82 * classes might already have added names to it.
84 * This is used by the vswitch at startup, so that it can delete any
85 * datapaths that are not configured.
87 * Some kinds of datapaths might not be practically enumerable, in which
88 * case this function may be a null pointer. */
89 int (*enumerate
)(struct svec
*all_dps
);
91 /* Attempts to open an existing dpif called 'name', if 'create' is false,
92 * or to open an existing dpif or create a new one, if 'create' is true.
94 * 'dpif_class' is the class of dpif to open.
96 * If successful, stores a pointer to the new dpif in '*dpifp', which must
97 * have class 'dpif_class'. On failure there are no requirements on what
98 * is stored in '*dpifp'. */
99 int (*open
)(const struct dpif_class
*dpif_class
,
100 const char *name
, bool create
, struct dpif
**dpifp
);
102 /* Closes 'dpif' and frees associated memory. */
103 void (*close
)(struct dpif
*dpif
);
105 /* Enumerates all names that may be used to open 'dpif' into 'all_names'.
106 * The Linux datapath, for example, supports opening a datapath both by
107 * number, e.g. "dp0", and by the name of the datapath's local port. For
108 * some datapaths, this might be an infinite set (e.g. in a file name,
109 * slashes may be duplicated any number of times), in which case only the
110 * names most likely to be used should be enumerated.
112 * The caller has already initialized 'all_names' and might already have
113 * added some names to it. This function should not disturb any existing
114 * names in 'all_names'.
116 * If a datapath class does not support multiple names for a datapath, this
117 * function may be a null pointer.
119 * This is used by the vswitch at startup, */
120 int (*get_all_names
)(const struct dpif
*dpif
, struct svec
*all_names
);
122 /* Attempts to destroy the dpif underlying 'dpif'.
124 * If successful, 'dpif' will not be used again except as an argument for
125 * the 'close' member function. */
126 int (*destroy
)(struct dpif
*dpif
);
128 /* Retrieves statistics for 'dpif' into 'stats'. */
129 int (*get_stats
)(const struct dpif
*dpif
, struct odp_stats
*stats
);
131 /* Retrieves 'dpif''s current treatment of IP fragments into '*drop_frags':
132 * true indicates that fragments are dropped, false indicates that
133 * fragments are treated in the same way as other IP packets (except that
134 * the L4 header cannot be read). */
135 int (*get_drop_frags
)(const struct dpif
*dpif
, bool *drop_frags
);
137 /* Changes 'dpif''s treatment of IP fragments to 'drop_frags', whose
138 * meaning is the same as for the get_drop_frags member function. */
139 int (*set_drop_frags
)(struct dpif
*dpif
, bool drop_frags
);
141 /* Adds 'netdev' as a new port in 'dpif'. If successful, sets '*port_no'
142 * to the new port's port number. */
143 int (*port_add
)(struct dpif
*dpif
, struct netdev
*netdev
,
146 /* Removes port numbered 'port_no' from 'dpif'. */
147 int (*port_del
)(struct dpif
*dpif
, uint16_t port_no
);
149 /* Queries 'dpif' for a port with the given 'port_no' or 'devname'. Stores
150 * information about the port into '*port' if successful.
152 * The caller takes ownership of data in 'port' and must free it with
153 * dpif_port_destroy() when it is no longer needed. */
154 int (*port_query_by_number
)(const struct dpif
*dpif
, uint16_t port_no
,
155 struct dpif_port
*port
);
156 int (*port_query_by_name
)(const struct dpif
*dpif
, const char *devname
,
157 struct dpif_port
*port
);
159 /* Returns one greater than the largest port number accepted in flow
161 int (*get_max_ports
)(const struct dpif
*dpif
);
163 /* Attempts to begin dumping the ports in a dpif. On success, returns 0
164 * and initializes '*statep' with any data needed for iteration. On
165 * failure, returns a positive errno value. */
166 int (*port_dump_start
)(const struct dpif
*dpif
, void **statep
);
168 /* Attempts to retrieve another port from 'dpif' for 'state', which was
169 * initialized by a successful call to the 'port_dump_start' function for
170 * 'dpif'. On success, stores a new dpif_port into 'port' and returns 0.
171 * Returns EOF if the end of the port table has been reached, or a positive
172 * errno value on error. This function will not be called again once it
173 * returns nonzero once for a given iteration (but the 'port_dump_done'
174 * function will be called afterward).
176 * The dpif provider retains ownership of the data stored in 'port'. It
177 * must remain valid until at least the next call to 'port_dump_next' or
178 * 'port_dump_done' for 'state'. */
179 int (*port_dump_next
)(const struct dpif
*dpif
, void *state
,
180 struct dpif_port
*port
);
182 /* Releases resources from 'dpif' for 'state', which was initialized by a
183 * successful call to the 'port_dump_start' function for 'dpif'. */
184 int (*port_dump_done
)(const struct dpif
*dpif
, void *state
);
186 /* Polls for changes in the set of ports in 'dpif'. If the set of ports in
187 * 'dpif' has changed, then this function should do one of the
190 * - Preferably: store the name of the device that was added to or deleted
191 * from 'dpif' in '*devnamep' and return 0. The caller is responsible
192 * for freeing '*devnamep' (with free()) when it no longer needs it.
194 * - Alternatively: return ENOBUFS, without indicating the device that was
197 * Occasional 'false positives', in which the function returns 0 while
198 * indicating a device that was not actually added or deleted or returns
199 * ENOBUFS without any change, are acceptable.
201 * If the set of ports in 'dpif' has not changed, returns EAGAIN. May also
202 * return other positive errno values to indicate that something has gone
204 int (*port_poll
)(const struct dpif
*dpif
, char **devnamep
);
206 /* Arranges for the poll loop to wake up when 'port_poll' will return a
207 * value other than EAGAIN. */
208 void (*port_poll_wait
)(const struct dpif
*dpif
);
210 /* Queries 'dpif' for a flow entry. The flow is specified by the Netlink
211 * attributes with types ODP_KEY_ATTR_* in the 'key_len' bytes starting at
214 * Returns 0 if successful. If no flow matches, returns ENOENT. On other
215 * failure, returns a positive errno value.
217 * If 'actionsp' is nonnull, then on success '*actionsp' must be set to an
218 * ofpbuf owned by the caller that contains the Netlink attributes for the
219 * flow's actions. The caller must free the ofpbuf (with ofpbuf_delete())
220 * when it is no longer needed.
222 * If 'stats' is nonnull, then on success it must be updated with the
223 * flow's statistics. */
224 int (*flow_get
)(const struct dpif
*dpif
,
225 const struct nlattr
*key
, size_t key_len
,
226 struct ofpbuf
**actionsp
, struct dpif_flow_stats
*stats
);
228 /* Adds or modifies a flow in 'dpif'. The flow is specified by the Netlink
229 * attributes with types ODP_KEY_ATTR_* in the 'key_len' bytes starting at
230 * 'key'. The associated actions are specified by the Netlink attributes
231 * with types ODPAT_* in the 'actions_len' bytes starting at 'actions'.
233 * - If the flow's key does not exist in 'dpif', then the flow will be
234 * added if 'flags' includes DPIF_FP_CREATE. Otherwise the operation
235 * will fail with ENOENT.
237 * If the operation succeeds, then 'stats', if nonnull, must be zeroed.
239 * - If the flow's key does exist in 'dpif', then the flow's actions will
240 * be updated if 'flags' includes DPIF_FP_MODIFY. Otherwise the
241 * operation will fail with EEXIST. If the flow's actions are updated,
242 * then its statistics will be zeroed if 'flags' includes
243 * DPIF_FP_ZERO_STATS, and left as-is otherwise.
245 * If the operation succeeds, then 'stats', if nonnull, must be set to
246 * the flow's statistics before the update.
248 int (*flow_put
)(struct dpif
*dpif
, enum dpif_flow_put_flags flags
,
249 const struct nlattr
*key
, size_t key_len
,
250 const struct nlattr
*actions
, size_t actions_len
,
251 struct dpif_flow_stats
*stats
);
253 /* Deletes a flow from 'dpif' and returns 0, or returns ENOENT if 'dpif'
254 * does not contain such a flow. The flow is specified by the Netlink
255 * attributes with types ODP_KEY_ATTR_* in the 'key_len' bytes starting at
258 * If the operation succeeds, then 'stats', if nonnull, must be set to the
259 * flow's statistics before its deletion. */
260 int (*flow_del
)(struct dpif
*dpif
,
261 const struct nlattr
*key
, size_t key_len
,
262 struct dpif_flow_stats
*stats
);
264 /* Deletes all flows from 'dpif' and clears all of its queues of received
266 int (*flow_flush
)(struct dpif
*dpif
);
268 /* Attempts to begin dumping the flows in a dpif. On success, returns 0
269 * and initializes '*statep' with any data needed for iteration. On
270 * failure, returns a positive errno value. */
271 int (*flow_dump_start
)(const struct dpif
*dpif
, void **statep
);
273 /* Attempts to retrieve another flow from 'dpif' for 'state', which was
274 * initialized by a successful call to the 'flow_dump_start' function for
275 * 'dpif'. On success, updates the output parameters as described below
276 * and returns 0. Returns EOF if the end of the flow table has been
277 * reached, or a positive errno value on error. This function will not be
278 * called again once it returns nonzero within a given iteration (but the
279 * 'flow_dump_done' function will be called afterward).
281 * On success, if 'key' and 'key_len' are nonnull then '*key' and
282 * '*key_len' must be set to Netlink attributes with types ODP_KEY_ATTR_*
283 * representing the dumped flow's key. If 'actions' and 'actions_len' are
284 * nonnull then they should be set to Netlink attributes with types ODPAT_*
285 * representing the dumped flow's actions. If 'stats' is nonnull then it
286 * should be set to the dumped flow's statistics.
288 * All of the returned data is owned by 'dpif', not by the caller, and the
289 * caller must not modify or free it. 'dpif' must guarantee that it
290 * remains accessible and unchanging until at least the next call to
291 * 'flow_dump_next' or 'flow_dump_done' for 'state'. */
292 int (*flow_dump_next
)(const struct dpif
*dpif
, void *state
,
293 const struct nlattr
**key
, size_t *key_len
,
294 const struct nlattr
**actions
, size_t *actions_len
,
295 const struct dpif_flow_stats
**stats
);
297 /* Releases resources from 'dpif' for 'state', which was initialized by a
298 * successful call to the 'flow_dump_start' function for 'dpif'. */
299 int (*flow_dump_done
)(const struct dpif
*dpif
, void *state
);
301 /* Performs the 'actions_len' bytes of actions in 'actions' on the Ethernet
302 * frame specified in 'packet'. */
303 int (*execute
)(struct dpif
*dpif
, const struct nlattr
*actions
,
304 size_t actions_len
, const struct ofpbuf
*packet
);
306 /* Retrieves 'dpif''s "listen mask" into '*listen_mask'. Each ODPL_* bit
307 * set in '*listen_mask' indicates the 'dpif' will receive messages of the
308 * corresponding type when it calls the recv member function. */
309 int (*recv_get_mask
)(const struct dpif
*dpif
, int *listen_mask
);
311 /* Sets 'dpif''s "listen mask" to 'listen_mask'. Each ODPL_* bit set in
312 * 'listen_mask' indicates the 'dpif' will receive messages of the
313 * corresponding type when it calls the recv member function. */
314 int (*recv_set_mask
)(struct dpif
*dpif
, int listen_mask
);
316 /* Retrieves 'dpif''s sFlow sampling probability into '*probability'.
317 * Return value is 0 or a positive errno value. EOPNOTSUPP indicates that
318 * the datapath does not support sFlow, as does a null pointer.
320 * '*probability' is expressed as the number of packets out of UINT_MAX to
321 * sample, e.g. probability/UINT_MAX is the probability of sampling a given
323 int (*get_sflow_probability
)(const struct dpif
*dpif
,
324 uint32_t *probability
);
326 /* Sets 'dpif''s sFlow sampling probability to 'probability'. Return value
327 * is 0 or a positive errno value. EOPNOTSUPP indicates that the datapath
328 * does not support sFlow, as does a null pointer.
330 * 'probability' is expressed as the number of packets out of UINT_MAX to
331 * sample, e.g. probability/UINT_MAX is the probability of sampling a given
333 int (*set_sflow_probability
)(struct dpif
*dpif
, uint32_t probability
);
335 /* Translates OpenFlow queue ID 'queue_id' (in host byte order) into a
336 * priority value for use in the ODPAT_SET_PRIORITY action in
338 int (*queue_to_priority
)(const struct dpif
*dpif
, uint32_t queue_id
,
341 /* Polls for an upcall from 'dpif'. If successful, stores the upcall into
342 * '*upcall'. Only upcalls of the types selected with the set_listen_mask
343 * member function should be received.
345 * The caller takes ownership of the data that 'upcall' points to.
346 * 'upcall->key' and 'upcall->actions' (if nonnull) point into data owned
347 * by 'upcall->packet', so their memory cannot be freed separately. (This
348 * is hardly a great way to do things but it works out OK for the dpif
349 * providers that exist so far.)
351 * For greatest efficiency, 'upcall->packet' should have at least
352 * offsetof(struct ofp_packet_in, data) bytes of headroom.
354 * This function must not block. If no upcall is pending when it is
355 * called, it should return EAGAIN without blocking. */
356 int (*recv
)(struct dpif
*dpif
, struct dpif_upcall
*upcall
);
358 /* Arranges for the poll loop to wake up when 'dpif' has a message queued
359 * to be received with the recv member function. */
360 void (*recv_wait
)(struct dpif
*dpif
);
362 /* Throws away any queued upcalls that 'dpif' currently has ready to
364 void (*recv_purge
)(struct dpif
*dpif
);
367 extern const struct dpif_class dpif_linux_class
;
368 extern const struct dpif_class dpif_netdev_class
;
374 #endif /* dpif-provider.h */