2 * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2016 Nicira, Inc.
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 NETDEV_PROVIDER_H
18 #define NETDEV_PROVIDER_H 1
20 /* Generic interface to network devices. */
22 #include "connectivity.h"
24 #include "openvswitch/list.h"
35 #define NETDEV_NUMA_UNSPEC OVS_NUMA_UNSPEC
37 /* A network device (e.g. an Ethernet device).
39 * Network device implementations may read these members but should not modify
42 /* The following do not change during the lifetime of a struct netdev. */
43 char *name; /* Name of network device. */
44 const struct netdev_class *netdev_class; /* Functions to control
47 /* A sequence number which indicates changes in one of 'netdev''s
48 * properties. It must be nonzero so that users have a value which
49 * they may use as a reset when tracking 'netdev'.
51 * Minimally, the sequence number is required to change whenever
52 * 'netdev''s flags, features, ethernet address, or carrier changes. */
55 /* A netdev provider might be unable to change some of the device's
56 * parameter (n_rxq, mtu) when the device is in use. In this case
57 * the provider can notify the upper layer by calling
58 * netdev_request_reconfigure(). The upper layer will react by stopping
59 * the operations on the device and calling netdev_reconfigure() to allow
60 * the configuration changes. 'last_reconfigure_seq' remembers the value
61 * of 'reconfigure_seq' when the last reconfiguration happened. */
62 struct seq *reconfigure_seq;
63 uint64_t last_reconfigure_seq;
65 /* The core netdev code initializes these at netdev construction and only
66 * provide read-only access to its client. Netdev implementations may
70 int ref_cnt; /* Times this devices was opened. */
71 struct shash_node *node; /* Pointer to element in global map. */
72 struct ovs_list saved_flags_list; /* Contains "struct netdev_saved_flags". */
76 netdev_change_seq_changed(const struct netdev *netdev_)
78 struct netdev *netdev = CONST_CAST(struct netdev *, netdev_);
79 seq_change(connectivity_seq_get());
81 if (!netdev->change_seq) {
87 netdev_request_reconfigure(struct netdev *netdev)
89 seq_change(netdev->reconfigure_seq);
92 const char *netdev_get_type(const struct netdev *);
93 const struct netdev_class *netdev_get_class(const struct netdev *);
94 const char *netdev_get_name(const struct netdev *);
95 struct netdev *netdev_from_name(const char *name);
96 void netdev_get_devices(const struct netdev_class *,
97 struct shash *device_list);
98 struct netdev **netdev_get_vports(size_t *size);
100 /* A data structure for capturing packets received by a network device.
102 * Network device implementations may read these members but should not modify
105 * None of these members change during the lifetime of a struct netdev_rxq. */
107 struct netdev *netdev; /* Owns a reference to the netdev. */
111 struct netdev *netdev_rxq_get_netdev(const struct netdev_rxq *);
113 /* Network device class structure, to be defined by each implementation of a
116 * These functions return 0 if successful or a positive errno value on failure,
117 * except where otherwise noted.
123 * These functions work primarily with two different kinds of data structures:
125 * - "struct netdev", which represents a network device.
127 * - "struct netdev_rxq", which represents a handle for capturing packets
128 * received on a network device
130 * Each of these data structures contains all of the implementation-independent
131 * generic state for the respective concept, called the "base" state. None of
132 * them contains any extra space for implementations to use. Instead, each
133 * implementation is expected to declare its own data structure that contains
134 * an instance of the generic data structure plus additional
135 * implementation-specific members, called the "derived" state. The
136 * implementation can use casts or (preferably) the CONTAINER_OF macro to
137 * obtain access to derived state given only a pointer to the embedded generic
144 * Four stylized functions accompany each of these data structures:
146 * "alloc" "construct" "destruct" "dealloc"
147 * ------------ ---------------- --------------- --------------
148 * netdev ->alloc ->construct ->destruct ->dealloc
149 * netdev_rxq ->rxq_alloc ->rxq_construct ->rxq_destruct ->rxq_dealloc
151 * Any instance of a given data structure goes through the following life
154 * 1. The client calls the "alloc" function to obtain raw memory. If "alloc"
155 * fails, skip all the other steps.
157 * 2. The client initializes all of the data structure's base state. If this
158 * fails, skip to step 7.
160 * 3. The client calls the "construct" function. The implementation
161 * initializes derived state. It may refer to the already-initialized
162 * base state. If "construct" fails, skip to step 6.
164 * 4. The data structure is now initialized and in use.
166 * 5. When the data structure is no longer needed, the client calls the
167 * "destruct" function. The implementation uninitializes derived state.
168 * The base state has not been uninitialized yet, so the implementation
169 * may still refer to it.
171 * 6. The client uninitializes all of the data structure's base state.
173 * 7. The client calls the "dealloc" to free the raw memory. The
174 * implementation must not refer to base or derived state in the data
175 * structure, because it has already been uninitialized.
177 * If netdev support multi-queue IO then netdev->construct should set initialize
178 * netdev->n_rxq to number of queues.
180 * Each "alloc" function allocates and returns a new instance of the respective
181 * data structure. The "alloc" function is not given any information about the
182 * use of the new data structure, so it cannot perform much initialization.
183 * Its purpose is just to ensure that the new data structure has enough room
184 * for base and derived state. It may return a null pointer if memory is not
185 * available, in which case none of the other functions is called.
187 * Each "construct" function initializes derived state in its respective data
188 * structure. When "construct" is called, all of the base state has already
189 * been initialized, so the "construct" function may refer to it. The
190 * "construct" function is allowed to fail, in which case the client calls the
191 * "dealloc" function (but not the "destruct" function).
193 * Each "destruct" function uninitializes and frees derived state in its
194 * respective data structure. When "destruct" is called, the base state has
195 * not yet been uninitialized, so the "destruct" function may refer to it. The
196 * "destruct" function is not allowed to fail.
198 * Each "dealloc" function frees raw memory that was allocated by the
199 * "alloc" function. The memory's base and derived members might not have ever
200 * been initialized (but if "construct" returned successfully, then it has been
201 * "destruct"ed already). The "dealloc" function is not allowed to fail.
204 * Device Change Notification
205 * ==========================
207 * Minimally, implementations are required to report changes to netdev flags,
208 * features, ethernet address or carrier through connectivity_seq. Changes to
209 * other properties are allowed to cause notification through this interface,
210 * although implementations should try to avoid this. connectivity_seq_get()
211 * can be used to acquire a reference to the struct seq. The interface is
212 * described in detail in seq.h. */
213 struct netdev_class {
214 /* Type of netdevs in this class, e.g. "system", "tap", "gre", etc.
216 * One of the providers should supply a "system" type, since this is
217 * the type assumed if no type is specified when opening a netdev.
218 * The "system" type corresponds to an existing network device on
222 /* If 'true' then this netdev should be polled by PMD threads. */
225 /* ## ------------------- ## */
226 /* ## Top-Level Functions ## */
227 /* ## ------------------- ## */
229 /* Called when the netdev provider is registered, typically at program
230 * startup. Returning an error from this function will prevent any network
231 * device in this class from being opened.
233 * This function may be set to null if a network device class needs no
234 * initialization at registration time. */
237 /* Performs periodic work needed by netdevs of this class. May be null if
238 * no periodic work is necessary. */
241 /* Arranges for poll_block() to wake up if the "run" member function needs
242 * to be called. Implementations are additionally required to wake
243 * whenever something changes in any of its netdevs which would cause their
244 * ->change_seq() function to change its result. May be null if nothing is
248 /* ## ---------------- ## */
249 /* ## netdev Functions ## */
250 /* ## ---------------- ## */
252 /* Life-cycle functions for a netdev. See the large comment above on
253 * struct netdev_class. */
254 struct netdev *(*alloc)(void);
255 int (*construct)(struct netdev *);
256 void (*destruct)(struct netdev *);
257 void (*dealloc)(struct netdev *);
259 /* Fetches the device 'netdev''s configuration, storing it in 'args'.
260 * The caller owns 'args' and pre-initializes it to an empty smap.
262 * If this netdev class does not have any configuration options, this may
263 * be a null pointer. */
264 int (*get_config)(const struct netdev *netdev, struct smap *args);
266 /* Changes the device 'netdev''s configuration to 'args'.
268 * If this netdev class does not support configuration, this may be a null
270 int (*set_config)(struct netdev *netdev, const struct smap *args);
272 /* Returns the tunnel configuration of 'netdev'. If 'netdev' is
273 * not a tunnel, returns null.
275 * If this function would always return null, it may be null instead. */
276 const struct netdev_tunnel_config *
277 (*get_tunnel_config)(const struct netdev *netdev);
279 /* Build Partial Tunnel header. Ethernet and ip header is already built,
280 * build_header() is suppose build protocol specific part of header. */
281 int (*build_header)(const struct netdev *, struct ovs_action_push_tnl *data,
282 const struct flow *tnl_flow);
284 /* build_header() can not build entire header for all packets for given
285 * flow. Push header is called for packet to build header specific to
286 * a packet on actual transmit. It uses partial header build by
287 * build_header() which is passed as data. */
288 void (*push_header)(struct dp_packet *packet,
289 const struct ovs_action_push_tnl *data);
291 /* Pop tunnel header from packet, build tunnel metadata and resize packet
292 * for further processing.
293 * Returns NULL in case of error or tunnel implementation queued packet for further
295 struct dp_packet * (*pop_header)(struct dp_packet *packet);
297 /* Returns the id of the numa node the 'netdev' is on. If there is no
298 * such info, returns NETDEV_NUMA_UNSPEC. */
299 int (*get_numa_id)(const struct netdev *netdev);
301 /* Configures the number of tx queues of 'netdev'. Returns 0 if successful,
302 * otherwise a positive errno value.
304 * 'n_txq' specifies the exact number of transmission queues to create.
305 * The caller will call netdev_send() concurrently from 'n_txq' different
306 * threads (with different qid). The netdev provider is responsible for
307 * making sure that these concurrent calls do not create a race condition
308 * by using multiple hw queues or locking.
310 * The caller will call netdev_reconfigure() (if necessary) before using
311 * netdev_send() on any of the newly configured queues, giving the provider
312 * a chance to adjust its settings.
314 * On error, the tx queue configuration is unchanged. */
315 int (*set_tx_multiq)(struct netdev *netdev, unsigned int n_txq);
317 /* Sends buffers on 'netdev'.
318 * Returns 0 if successful (for every buffer), otherwise a positive errno
319 * value. Returns EAGAIN without blocking if one or more packets cannot be
320 * queued immediately. Returns EMSGSIZE if a partial packet was transmitted
321 * or if a packet is too big or too small to transmit on the device.
323 * If the function returns a non-zero value, some of the packets might have
326 * If 'may_steal' is false, the caller retains ownership of all the
327 * packets. If 'may_steal' is true, the caller transfers ownership of all
328 * the packets to the network device, regardless of success.
330 * The network device is expected to maintain one or more packet
331 * transmission queues, so that the caller does not ordinarily have to
332 * do additional queuing of packets. 'qid' specifies the queue to use
333 * and can be ignored if the implementation does not support multiple
336 * May return EOPNOTSUPP if a network device does not implement packet
337 * transmission through this interface. This function may be set to null
338 * if it would always return EOPNOTSUPP anyhow. (This will prevent the
339 * network device from being usefully used by the netdev-based "userspace
340 * datapath". It will also prevent the OVS implementation of bonding from
341 * working properly over 'netdev'.) */
342 int (*send)(struct netdev *netdev, int qid, struct dp_packet **buffers,
343 int cnt, bool may_steal);
345 /* Registers with the poll loop to wake up from the next call to
346 * poll_block() when the packet transmission queue for 'netdev' has
347 * sufficient room to transmit a packet with netdev_send().
349 * The network device is expected to maintain one or more packet
350 * transmission queues, so that the caller does not ordinarily have to
351 * do additional queuing of packets. 'qid' specifies the queue to use
352 * and can be ignored if the implementation does not support multiple
355 * May be null if not needed, such as for a network device that does not
356 * implement packet transmission through the 'send' member function. */
357 void (*send_wait)(struct netdev *netdev, int qid);
359 /* Sets 'netdev''s Ethernet address to 'mac' */
360 int (*set_etheraddr)(struct netdev *netdev, const struct eth_addr mac);
362 /* Retrieves 'netdev''s Ethernet address into 'mac'.
364 * This address will be advertised as 'netdev''s MAC address through the
365 * OpenFlow protocol, among other uses. */
366 int (*get_etheraddr)(const struct netdev *netdev, struct eth_addr *mac);
368 /* Retrieves 'netdev''s MTU into '*mtup'.
370 * The MTU is the maximum size of transmitted (and received) packets, in
371 * bytes, not including the hardware header; thus, this is typically 1500
372 * bytes for Ethernet devices.
374 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
375 * this function should return EOPNOTSUPP. This function may be set to
376 * null if it would always return EOPNOTSUPP. */
377 int (*get_mtu)(const struct netdev *netdev, int *mtup);
379 /* Sets 'netdev''s MTU to 'mtu'.
381 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
382 * this function should return EOPNOTSUPP. This function may be set to
383 * null if it would always return EOPNOTSUPP. */
384 int (*set_mtu)(const struct netdev *netdev, int mtu);
386 /* Returns the ifindex of 'netdev', if successful, as a positive number.
387 * On failure, returns a negative errno value.
389 * The desired semantics of the ifindex value are a combination of those
390 * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An
391 * ifindex value should be unique within a host and remain stable at least
392 * until reboot. SNMP says an ifindex "ranges between 1 and the value of
393 * ifNumber" but many systems do not follow this rule anyhow.
395 * This function may be set to null if it would always return -EOPNOTSUPP.
397 int (*get_ifindex)(const struct netdev *netdev);
399 /* Sets 'carrier' to true if carrier is active (link light is on) on
402 * May be null if device does not provide carrier status (will be always
403 * up as long as device is up).
405 int (*get_carrier)(const struct netdev *netdev, bool *carrier);
407 /* Returns the number of times 'netdev''s carrier has changed since being
410 * If null, callers will assume the number of carrier resets is zero. */
411 long long int (*get_carrier_resets)(const struct netdev *netdev);
413 /* Forces ->get_carrier() to poll 'netdev''s MII registers for link status
414 * instead of checking 'netdev''s carrier. 'netdev''s MII registers will
415 * be polled once every 'interval' milliseconds. If 'netdev' does not
416 * support MII, another method may be used as a fallback. If 'interval' is
417 * less than or equal to zero, reverts ->get_carrier() to its normal
420 * Most network devices won't support this feature and will set this
421 * function pointer to NULL, which is equivalent to returning EOPNOTSUPP.
423 int (*set_miimon_interval)(struct netdev *netdev, long long int interval);
425 /* Retrieves current device stats for 'netdev' into 'stats'.
427 * A network device that supports some statistics but not others, it should
428 * set the values of the unsupported statistics to all-1-bits
430 int (*get_stats)(const struct netdev *netdev, struct netdev_stats *);
432 /* Stores the features supported by 'netdev' into each of '*current',
433 * '*advertised', '*supported', and '*peer'. Each value is a bitmap of
436 * This function may be set to null if it would always return EOPNOTSUPP.
438 int (*get_features)(const struct netdev *netdev,
439 enum netdev_features *current,
440 enum netdev_features *advertised,
441 enum netdev_features *supported,
442 enum netdev_features *peer);
444 /* Set the features advertised by 'netdev' to 'advertise', which is a
445 * set of NETDEV_F_* bits.
447 * This function may be set to null for a network device that does not
448 * support configuring advertisements. */
449 int (*set_advertisements)(struct netdev *netdev,
450 enum netdev_features advertise);
452 /* Attempts to set input rate limiting (policing) policy, such that up to
453 * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative
454 * burst size of 'kbits' kb.
456 * This function may be set to null if policing is not supported. */
457 int (*set_policing)(struct netdev *netdev, unsigned int kbits_rate,
458 unsigned int kbits_burst);
460 /* Adds to 'types' all of the forms of QoS supported by 'netdev', or leaves
461 * it empty if 'netdev' does not support QoS. Any names added to 'types'
462 * should be documented as valid for the "type" column in the "QoS" table
463 * in vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
465 * Every network device must support disabling QoS with a type of "", but
466 * this function must not add "" to 'types'.
468 * The caller is responsible for initializing 'types' (e.g. with
469 * sset_init()) before calling this function. The caller retains ownership
472 * May be NULL if 'netdev' does not support QoS at all. */
473 int (*get_qos_types)(const struct netdev *netdev, struct sset *types);
475 /* Queries 'netdev' for its capabilities regarding the specified 'type' of
476 * QoS. On success, initializes 'caps' with the QoS capabilities.
478 * Should return EOPNOTSUPP if 'netdev' does not support 'type'. May be
479 * NULL if 'netdev' does not support QoS at all. */
480 int (*get_qos_capabilities)(const struct netdev *netdev,
482 struct netdev_qos_capabilities *caps);
484 /* Queries 'netdev' about its currently configured form of QoS. If
485 * successful, stores the name of the current form of QoS into '*typep'
486 * and any details of configuration as string key-value pairs in
489 * A '*typep' of "" indicates that QoS is currently disabled on 'netdev'.
491 * The caller initializes 'details' before calling this function. The
492 * caller takes ownership of the string key-values pairs added to
495 * The netdev retains ownership of '*typep'.
497 * '*typep' will be one of the types returned by netdev_get_qos_types() for
498 * 'netdev'. The contents of 'details' should be documented as valid for
499 * '*typep' in the "other_config" column in the "QoS" table in
500 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
502 * May be NULL if 'netdev' does not support QoS at all. */
503 int (*get_qos)(const struct netdev *netdev,
504 const char **typep, struct smap *details);
506 /* Attempts to reconfigure QoS on 'netdev', changing the form of QoS to
507 * 'type' with details of configuration from 'details'.
509 * On error, the previous QoS configuration is retained.
511 * When this function changes the type of QoS (not just 'details'), this
512 * also resets all queue configuration for 'netdev' to their defaults
513 * (which depend on the specific type of QoS). Otherwise, the queue
514 * configuration for 'netdev' is unchanged.
516 * 'type' should be "" (to disable QoS) or one of the types returned by
517 * netdev_get_qos_types() for 'netdev'. The contents of 'details' should
518 * be documented as valid for the given 'type' in the "other_config" column
519 * in the "QoS" table in vswitchd/vswitch.xml (which is built as
520 * ovs-vswitchd.conf.db(8)).
522 * May be NULL if 'netdev' does not support QoS at all. */
523 int (*set_qos)(struct netdev *netdev,
524 const char *type, const struct smap *details);
526 /* Queries 'netdev' for information about the queue numbered 'queue_id'.
527 * If successful, adds that information as string key-value pairs to
528 * 'details'. Returns 0 if successful, otherwise a positive errno value.
530 * Should return EINVAL if 'queue_id' is greater than or equal to the
531 * number of supported queues (as reported in the 'n_queues' member of
532 * struct netdev_qos_capabilities by 'get_qos_capabilities').
534 * The caller initializes 'details' before calling this function. The
535 * caller takes ownership of the string key-values pairs added to
538 * The returned contents of 'details' should be documented as valid for the
539 * given 'type' in the "other_config" column in the "Queue" table in
540 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
542 int (*get_queue)(const struct netdev *netdev,
543 unsigned int queue_id, struct smap *details);
545 /* Configures the queue numbered 'queue_id' on 'netdev' with the key-value
546 * string pairs in 'details'. The contents of 'details' should be
547 * documented as valid for the given 'type' in the "other_config" column in
548 * the "Queue" table in vswitchd/vswitch.xml (which is built as
549 * ovs-vswitchd.conf.db(8)). Returns 0 if successful, otherwise a positive
550 * errno value. On failure, the given queue's configuration should be
553 * Should return EINVAL if 'queue_id' is greater than or equal to the
554 * number of supported queues (as reported in the 'n_queues' member of
555 * struct netdev_qos_capabilities by 'get_qos_capabilities'), or if
556 * 'details' is invalid for the type of queue.
558 * This function does not modify 'details', and the caller retains
561 * May be NULL if 'netdev' does not support QoS at all. */
562 int (*set_queue)(struct netdev *netdev,
563 unsigned int queue_id, const struct smap *details);
565 /* Attempts to delete the queue numbered 'queue_id' from 'netdev'.
567 * Should return EINVAL if 'queue_id' is greater than or equal to the
568 * number of supported queues (as reported in the 'n_queues' member of
569 * struct netdev_qos_capabilities by 'get_qos_capabilities'). Should
570 * return EOPNOTSUPP if 'queue_id' is valid but may not be deleted (e.g. if
571 * 'netdev' has a fixed set of queues with the current QoS mode).
573 * May be NULL if 'netdev' does not support QoS at all, or if all of its
574 * QoS modes have fixed sets of queues. */
575 int (*delete_queue)(struct netdev *netdev, unsigned int queue_id);
577 /* Obtains statistics about 'queue_id' on 'netdev'. Fills 'stats' with the
578 * queue's statistics. May set individual members of 'stats' to all-1-bits
579 * if the statistic is unavailable.
581 * May be NULL if 'netdev' does not support QoS at all. */
582 int (*get_queue_stats)(const struct netdev *netdev, unsigned int queue_id,
583 struct netdev_queue_stats *stats);
585 /* Attempts to begin dumping the queues in 'netdev'. On success, returns 0
586 * and initializes '*statep' with any data needed for iteration. On
587 * failure, returns a positive errno value.
589 * May be NULL if 'netdev' does not support QoS at all. */
590 int (*queue_dump_start)(const struct netdev *netdev, void **statep);
592 /* Attempts to retrieve another queue from 'netdev' for 'state', which was
593 * initialized by a successful call to the 'queue_dump_start' function for
594 * 'netdev'. On success, stores a queue ID into '*queue_id' and fills
595 * 'details' with the configuration of the queue with that ID. Returns EOF
596 * if the last queue has been dumped, or a positive errno value on error.
597 * This function will not be called again once it returns nonzero once for
598 * a given iteration (but the 'queue_dump_done' function will be called
601 * The caller initializes and clears 'details' before calling this
602 * function. The caller takes ownership of the string key-values pairs
603 * added to 'details'.
605 * The returned contents of 'details' should be documented as valid for the
606 * given 'type' in the "other_config" column in the "Queue" table in
607 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
609 * May be NULL if 'netdev' does not support QoS at all. */
610 int (*queue_dump_next)(const struct netdev *netdev, void *state,
611 unsigned int *queue_id, struct smap *details);
613 /* Releases resources from 'netdev' for 'state', which was initialized by a
614 * successful call to the 'queue_dump_start' function for 'netdev'.
616 * May be NULL if 'netdev' does not support QoS at all. */
617 int (*queue_dump_done)(const struct netdev *netdev, void *state);
619 /* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
620 * ID, its statistics, and the 'aux' specified by the caller. The order of
621 * iteration is unspecified, but (when successful) each queue must be
622 * visited exactly once.
624 * 'cb' will not modify or free the statistics passed in. */
625 int (*dump_queue_stats)(const struct netdev *netdev,
626 void (*cb)(unsigned int queue_id,
627 struct netdev_queue_stats *,
631 /* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask. If
632 * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared.
634 * This function may be set to null if it would always return EOPNOTSUPP
636 int (*set_in4)(struct netdev *netdev, struct in_addr addr,
637 struct in_addr mask);
639 /* Returns all assigned IP address to 'netdev' and returns 0.
640 * API allocates array of address and masks and set it to
641 * '*addr' and '*mask'.
642 * Otherwise, returns a positive errno value and sets '*addr', '*mask
643 * and '*n_addr' to NULL.
645 * The following error values have well-defined meanings:
647 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv6 address.
649 * - EOPNOTSUPP: No IPv6 network stack attached to 'netdev'.
651 * 'addr' may be null, in which case the address itself is not reported. */
652 int (*get_addr_list)(const struct netdev *netdev, struct in6_addr **in,
653 struct in6_addr **mask, int *n_in6);
655 /* Adds 'router' as a default IP gateway for the TCP/IP stack that
656 * corresponds to 'netdev'.
658 * This function may be set to null if it would always return EOPNOTSUPP
660 int (*add_router)(struct netdev *netdev, struct in_addr router);
662 /* Looks up the next hop for 'host' in the host's routing table. If
663 * successful, stores the next hop gateway's address (0 if 'host' is on a
664 * directly connected network) in '*next_hop' and a copy of the name of the
665 * device to reach 'host' in '*netdev_name', and returns 0. The caller is
666 * responsible for freeing '*netdev_name' (by calling free()).
668 * This function may be set to null if it would always return EOPNOTSUPP
670 int (*get_next_hop)(const struct in_addr *host, struct in_addr *next_hop,
673 /* Retrieves driver information of the device.
675 * Populates 'smap' with key-value pairs representing the status of the
676 * device. 'smap' is a set of key-value string pairs representing netdev
677 * type specific information. For more information see
678 * ovs-vswitchd.conf.db(5).
680 * The caller is responsible for destroying 'smap' and its data.
682 * This function may be set to null if it would always return EOPNOTSUPP
684 int (*get_status)(const struct netdev *netdev, struct smap *smap);
686 /* Looks up the ARP table entry for 'ip' on 'netdev' and stores the
687 * corresponding MAC address in 'mac'. A return value of ENXIO, in
688 * particular, indicates that there is no ARP table entry for 'ip' on
691 * This function may be set to null if it would always return EOPNOTSUPP
693 int (*arp_lookup)(const struct netdev *netdev, ovs_be32 ip,
694 struct eth_addr *mac);
696 /* Retrieves the current set of flags on 'netdev' into '*old_flags'. Then,
697 * turns off the flags that are set to 1 in 'off' and turns on the flags
698 * that are set to 1 in 'on'. (No bit will be set to 1 in both 'off' and
699 * 'on'; that is, off & on == 0.)
701 * This function may be invoked from a signal handler. Therefore, it
702 * should not do anything that is not signal-safe (such as logging). */
703 int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
704 enum netdev_flags on, enum netdev_flags *old_flags);
706 /* If the provider called netdev_request_reconfigure(), the upper layer
707 * will eventually call this. The provider can update the device
708 * configuration knowing that the upper layer will not call rxq_recv() or
709 * send() until this function returns.
711 * On error, the configuration is indeterminant and the device cannot be
712 * used to send and receive packets until a successful configuration is
714 int (*reconfigure)(struct netdev *netdev);
715 /* ## -------------------- ## */
716 /* ## netdev_rxq Functions ## */
717 /* ## -------------------- ## */
719 /* If a particular netdev class does not support receiving packets, all these
720 * function pointers must be NULL. */
722 /* Life-cycle functions for a netdev_rxq. See the large comment above on
723 * struct netdev_class. */
724 struct netdev_rxq *(*rxq_alloc)(void);
725 int (*rxq_construct)(struct netdev_rxq *);
726 void (*rxq_destruct)(struct netdev_rxq *);
727 void (*rxq_dealloc)(struct netdev_rxq *);
729 /* Attempts to receive a batch of packets from 'rx'. The caller supplies
730 * 'pkts' as the pointer to the beginning of an array of MAX_RX_BATCH
731 * pointers to dp_packet. If successful, the implementation stores
732 * pointers to up to MAX_RX_BATCH dp_packets into the array, transferring
733 * ownership of the packets to the caller, stores the number of received
734 * packets into '*cnt', and returns 0.
736 * The implementation does not necessarily initialize any non-data members
737 * of 'pkts'. That is, the caller must initialize layer pointers and
738 * metadata itself, if desired, e.g. with pkt_metadata_init() and
739 * miniflow_extract().
741 * Implementations should allocate buffers with DP_NETDEV_HEADROOM bytes of
744 * Returns EAGAIN immediately if no packet is ready to be received or
745 * another positive errno value if an error was encountered. */
746 int (*rxq_recv)(struct netdev_rxq *rx, struct dp_packet **pkts,
749 /* Registers with the poll loop to wake up from the next call to
750 * poll_block() when a packet is ready to be received with
751 * netdev_rxq_recv() on 'rx'. */
752 void (*rxq_wait)(struct netdev_rxq *rx);
754 /* Discards all packets waiting to be received from 'rx'. */
755 int (*rxq_drain)(struct netdev_rxq *rx);
758 int netdev_register_provider(const struct netdev_class *);
759 int netdev_unregister_provider(const char *type);
761 #if defined(__FreeBSD__) || defined(__NetBSD__)
762 extern const struct netdev_class netdev_bsd_class;
763 #elif defined(_WIN32)
764 extern const struct netdev_class netdev_windows_class;
766 extern const struct netdev_class netdev_linux_class;
768 extern const struct netdev_class netdev_internal_class;
769 extern const struct netdev_class netdev_tap_class;
775 #endif /* netdev.h */