2 * Copyright (c) 2009, 2010, 2011, 2012, 2013 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"
33 /* A network device (e.g. an Ethernet device).
35 * Network device implementations may read these members but should not modify
38 /* The following do not change during the lifetime of a struct netdev. */
39 char *name; /* Name of network device. */
40 const struct netdev_class *netdev_class; /* Functions to control
43 /* A sequence number which indicates changes in one of 'netdev''s
44 * properties. It must be nonzero so that users have a value which
45 * they may use as a reset when tracking 'netdev'.
47 * Minimally, the sequence number is required to change whenever
48 * 'netdev''s flags, features, ethernet address, or carrier changes. */
51 /* The following are protected by 'netdev_mutex' (internal to netdev.c). */
53 int ref_cnt; /* Times this devices was opened. */
54 struct shash_node *node; /* Pointer to element in global map. */
55 struct list saved_flags_list; /* Contains "struct netdev_saved_flags". */
59 netdev_change_seq_changed(struct netdev *netdev)
61 seq_change(connectivity_seq_get());
63 if (!netdev->change_seq) {
68 const char *netdev_get_type(const struct netdev *);
69 const struct netdev_class *netdev_get_class(const struct netdev *);
70 const char *netdev_get_name(const struct netdev *);
71 struct netdev *netdev_from_name(const char *name);
72 void netdev_get_devices(const struct netdev_class *,
73 struct shash *device_list);
74 struct netdev **netdev_get_vports(size_t *size);
76 /* A data structure for capturing packets received by a network device.
78 * Network device implementations may read these members but should not modify
81 * None of these members change during the lifetime of a struct netdev_rxq. */
83 struct netdev *netdev; /* Owns a reference to the netdev. */
87 struct netdev *netdev_rxq_get_netdev(const struct netdev_rxq *);
89 /* Network device class structure, to be defined by each implementation of a
92 * These functions return 0 if successful or a positive errno value on failure,
93 * except where otherwise noted.
99 * These functions work primarily with two different kinds of data structures:
101 * - "struct netdev", which represents a network device.
103 * - "struct netdev_rxq", which represents a handle for capturing packets
104 * received on a network device
106 * Each of these data structures contains all of the implementation-independent
107 * generic state for the respective concept, called the "base" state. None of
108 * them contains any extra space for implementations to use. Instead, each
109 * implementation is expected to declare its own data structure that contains
110 * an instance of the generic data structure plus additional
111 * implementation-specific members, called the "derived" state. The
112 * implementation can use casts or (preferably) the CONTAINER_OF macro to
113 * obtain access to derived state given only a pointer to the embedded generic
120 * Four stylized functions accompany each of these data structures:
122 * "alloc" "construct" "destruct" "dealloc"
123 * ------------ ---------------- --------------- --------------
124 * netdev ->alloc ->construct ->destruct ->dealloc
125 * netdev_rxq ->rxq_alloc ->rxq_construct ->rxq_destruct ->rxq_dealloc
127 * Any instance of a given data structure goes through the following life
130 * 1. The client calls the "alloc" function to obtain raw memory. If "alloc"
131 * fails, skip all the other steps.
133 * 2. The client initializes all of the data structure's base state. If this
134 * fails, skip to step 7.
136 * 3. The client calls the "construct" function. The implementation
137 * initializes derived state. It may refer to the already-initialized
138 * base state. If "construct" fails, skip to step 6.
140 * 4. The data structure is now initialized and in use.
142 * 5. When the data structure is no longer needed, the client calls the
143 * "destruct" function. The implementation uninitializes derived state.
144 * The base state has not been uninitialized yet, so the implementation
145 * may still refer to it.
147 * 6. The client uninitializes all of the data structure's base state.
149 * 7. The client calls the "dealloc" to free the raw memory. The
150 * implementation must not refer to base or derived state in the data
151 * structure, because it has already been uninitialized.
153 * If netdev support multi-queue IO then netdev->construct should set initialize
154 * netdev->n_rxq to number of queues.
156 * Each "alloc" function allocates and returns a new instance of the respective
157 * data structure. The "alloc" function is not given any information about the
158 * use of the new data structure, so it cannot perform much initialization.
159 * Its purpose is just to ensure that the new data structure has enough room
160 * for base and derived state. It may return a null pointer if memory is not
161 * available, in which case none of the other functions is called.
163 * Each "construct" function initializes derived state in its respective data
164 * structure. When "construct" is called, all of the base state has already
165 * been initialized, so the "construct" function may refer to it. The
166 * "construct" function is allowed to fail, in which case the client calls the
167 * "dealloc" function (but not the "destruct" function).
169 * Each "destruct" function uninitializes and frees derived state in its
170 * respective data structure. When "destruct" is called, the base state has
171 * not yet been uninitialized, so the "destruct" function may refer to it. The
172 * "destruct" function is not allowed to fail.
174 * Each "dealloc" function frees raw memory that was allocated by the the
175 * "alloc" function. The memory's base and derived members might not have ever
176 * been initialized (but if "construct" returned successfully, then it has been
177 * "destruct"ed already). The "dealloc" function is not allowed to fail.
180 * Device Change Notification
181 * ==========================
183 * Minimally, implementations are required to report changes to netdev flags,
184 * features, ethernet address or carrier through connectivity_seq. Changes to
185 * other properties are allowed to cause notification through this interface,
186 * although implementations should try to avoid this. connectivity_seq_get()
187 * can be used to acquire a reference to the struct seq. The interface is
188 * described in detail in seq.h. */
189 struct netdev_class {
190 /* Type of netdevs in this class, e.g. "system", "tap", "gre", etc.
192 * One of the providers should supply a "system" type, since this is
193 * the type assumed if no type is specified when opening a netdev.
194 * The "system" type corresponds to an existing network device on
198 /* ## ------------------- ## */
199 /* ## Top-Level Functions ## */
200 /* ## ------------------- ## */
202 /* Called when the netdev provider is registered, typically at program
203 * startup. Returning an error from this function will prevent any network
204 * device in this class from being opened.
206 * This function may be set to null if a network device class needs no
207 * initialization at registration time. */
210 /* Performs periodic work needed by netdevs of this class. May be null if
211 * no periodic work is necessary. */
214 /* Arranges for poll_block() to wake up if the "run" member function needs
215 * to be called. Implementations are additionally required to wake
216 * whenever something changes in any of its netdevs which would cause their
217 * ->change_seq() function to change its result. May be null if nothing is
221 /* ## ---------------- ## */
222 /* ## netdev Functions ## */
223 /* ## ---------------- ## */
225 /* Life-cycle functions for a netdev. See the large comment above on
226 * struct netdev_class. */
227 struct netdev *(*alloc)(void);
228 int (*construct)(struct netdev *);
229 void (*destruct)(struct netdev *);
230 void (*dealloc)(struct netdev *);
232 /* Fetches the device 'netdev''s configuration, storing it in 'args'.
233 * The caller owns 'args' and pre-initializes it to an empty smap.
235 * If this netdev class does not have any configuration options, this may
236 * be a null pointer. */
237 int (*get_config)(const struct netdev *netdev, struct smap *args);
239 /* Changes the device 'netdev''s configuration to 'args'.
241 * If this netdev class does not support configuration, this may be a null
243 int (*set_config)(struct netdev *netdev, const struct smap *args);
245 /* Returns the tunnel configuration of 'netdev'. If 'netdev' is
246 * not a tunnel, returns null.
248 * If this function would always return null, it may be null instead. */
249 const struct netdev_tunnel_config *
250 (*get_tunnel_config)(const struct netdev *netdev);
252 /* Sends the buffer on 'netdev'.
253 * Returns 0 if successful, otherwise a positive errno value. Returns
254 * EAGAIN without blocking if the packet cannot be queued immediately.
255 * Returns EMSGSIZE if a partial packet was transmitted or if the packet
256 * is too big or too small to transmit on the device.
258 * To retain ownership of 'buffer' caller can set may_steal to false.
260 * The network device is expected to maintain a packet transmission queue,
261 * so that the caller does not ordinarily have to do additional queuing of
264 * May return EOPNOTSUPP if a network device does not implement packet
265 * transmission through this interface. This function may be set to null
266 * if it would always return EOPNOTSUPP anyhow. (This will prevent the
267 * network device from being usefully used by the netdev-based "userspace
268 * datapath". It will also prevent the OVS implementation of bonding from
269 * working properly over 'netdev'.) */
270 int (*send)(struct netdev *netdev, struct ofpbuf *buffer, bool may_steal);
272 /* Registers with the poll loop to wake up from the next call to
273 * poll_block() when the packet transmission queue for 'netdev' has
274 * sufficient room to transmit a packet with netdev_send().
276 * The network device is expected to maintain a packet transmission queue,
277 * so that the caller does not ordinarily have to do additional queuing of
278 * packets. Thus, this function is unlikely to ever be useful.
280 * May be null if not needed, such as for a network device that does not
281 * implement packet transmission through the 'send' member function. */
282 void (*send_wait)(struct netdev *netdev);
284 /* Sets 'netdev''s Ethernet address to 'mac' */
285 int (*set_etheraddr)(struct netdev *netdev, const uint8_t mac[6]);
287 /* Retrieves 'netdev''s Ethernet address into 'mac'.
289 * This address will be advertised as 'netdev''s MAC address through the
290 * OpenFlow protocol, among other uses. */
291 int (*get_etheraddr)(const struct netdev *netdev, uint8_t mac[6]);
293 /* Retrieves 'netdev''s MTU into '*mtup'.
295 * The MTU is the maximum size of transmitted (and received) packets, in
296 * bytes, not including the hardware header; thus, this is typically 1500
297 * bytes for Ethernet devices.
299 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
300 * this function should return EOPNOTSUPP. This function may be set to
301 * null if it would always return EOPNOTSUPP. */
302 int (*get_mtu)(const struct netdev *netdev, int *mtup);
304 /* Sets 'netdev''s MTU to 'mtu'.
306 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
307 * this function should return EOPNOTSUPP. This function may be set to
308 * null if it would always return EOPNOTSUPP. */
309 int (*set_mtu)(const struct netdev *netdev, int mtu);
311 /* Returns the ifindex of 'netdev', if successful, as a positive number.
312 * On failure, returns a negative errno value.
314 * The desired semantics of the ifindex value are a combination of those
315 * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An
316 * ifindex value should be unique within a host and remain stable at least
317 * until reboot. SNMP says an ifindex "ranges between 1 and the value of
318 * ifNumber" but many systems do not follow this rule anyhow.
320 * This function may be set to null if it would always return -EOPNOTSUPP.
322 int (*get_ifindex)(const struct netdev *netdev);
324 /* Sets 'carrier' to true if carrier is active (link light is on) on
327 * May be null if device does not provide carrier status (will be always
328 * up as long as device is up).
330 int (*get_carrier)(const struct netdev *netdev, bool *carrier);
332 /* Returns the number of times 'netdev''s carrier has changed since being
335 * If null, callers will assume the number of carrier resets is zero. */
336 long long int (*get_carrier_resets)(const struct netdev *netdev);
338 /* Forces ->get_carrier() to poll 'netdev''s MII registers for link status
339 * instead of checking 'netdev''s carrier. 'netdev''s MII registers will
340 * be polled once ever 'interval' milliseconds. If 'netdev' does not
341 * support MII, another method may be used as a fallback. If 'interval' is
342 * less than or equal to zero, reverts ->get_carrier() to its normal
345 * Most network devices won't support this feature and will set this
346 * function pointer to NULL, which is equivalent to returning EOPNOTSUPP.
348 int (*set_miimon_interval)(struct netdev *netdev, long long int interval);
350 /* Retrieves current device stats for 'netdev' into 'stats'.
352 * A network device that supports some statistics but not others, it should
353 * set the values of the unsupported statistics to all-1-bits
355 int (*get_stats)(const struct netdev *netdev, struct netdev_stats *);
357 /* Sets the device stats for 'netdev' to 'stats'.
359 * Most network devices won't support this feature and will set this
360 * function pointer to NULL, which is equivalent to returning EOPNOTSUPP.
362 * Some network devices might only allow setting their stats to 0. */
363 int (*set_stats)(struct netdev *netdev, const struct netdev_stats *);
365 /* Stores the features supported by 'netdev' into each of '*current',
366 * '*advertised', '*supported', and '*peer'. Each value is a bitmap of
369 * This function may be set to null if it would always return EOPNOTSUPP.
371 int (*get_features)(const struct netdev *netdev,
372 enum netdev_features *current,
373 enum netdev_features *advertised,
374 enum netdev_features *supported,
375 enum netdev_features *peer);
377 /* Set the features advertised by 'netdev' to 'advertise', which is a
378 * set of NETDEV_F_* bits.
380 * This function may be set to null for a network device that does not
381 * support configuring advertisements. */
382 int (*set_advertisements)(struct netdev *netdev,
383 enum netdev_features advertise);
385 /* Attempts to set input rate limiting (policing) policy, such that up to
386 * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative
387 * burst size of 'kbits' kb.
389 * This function may be set to null if policing is not supported. */
390 int (*set_policing)(struct netdev *netdev, unsigned int kbits_rate,
391 unsigned int kbits_burst);
393 /* Adds to 'types' all of the forms of QoS supported by 'netdev', or leaves
394 * it empty if 'netdev' does not support QoS. Any names added to 'types'
395 * should be documented as valid for the "type" column in the "QoS" table
396 * in vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
398 * Every network device must support disabling QoS with a type of "", but
399 * this function must not add "" to 'types'.
401 * The caller is responsible for initializing 'types' (e.g. with
402 * sset_init()) before calling this function. The caller retains ownership
405 * May be NULL if 'netdev' does not support QoS at all. */
406 int (*get_qos_types)(const struct netdev *netdev, struct sset *types);
408 /* Queries 'netdev' for its capabilities regarding the specified 'type' of
409 * QoS. On success, initializes 'caps' with the QoS capabilities.
411 * Should return EOPNOTSUPP if 'netdev' does not support 'type'. May be
412 * NULL if 'netdev' does not support QoS at all. */
413 int (*get_qos_capabilities)(const struct netdev *netdev,
415 struct netdev_qos_capabilities *caps);
417 /* Queries 'netdev' about its currently configured form of QoS. If
418 * successful, stores the name of the current form of QoS into '*typep'
419 * and any details of configuration as string key-value pairs in
422 * A '*typep' of "" indicates that QoS is currently disabled on 'netdev'.
424 * The caller initializes 'details' before calling this function. The
425 * caller takes ownership of the string key-values pairs added to
428 * The netdev retains ownership of '*typep'.
430 * '*typep' will be one of the types returned by netdev_get_qos_types() for
431 * 'netdev'. The contents of 'details' should be documented as valid for
432 * '*typep' in the "other_config" column in the "QoS" table in
433 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
435 * May be NULL if 'netdev' does not support QoS at all. */
436 int (*get_qos)(const struct netdev *netdev,
437 const char **typep, struct smap *details);
439 /* Attempts to reconfigure QoS on 'netdev', changing the form of QoS to
440 * 'type' with details of configuration from 'details'.
442 * On error, the previous QoS configuration is retained.
444 * When this function changes the type of QoS (not just 'details'), this
445 * also resets all queue configuration for 'netdev' to their defaults
446 * (which depend on the specific type of QoS). Otherwise, the queue
447 * configuration for 'netdev' is unchanged.
449 * 'type' should be "" (to disable QoS) or one of the types returned by
450 * netdev_get_qos_types() for 'netdev'. The contents of 'details' should
451 * be documented as valid for the given 'type' in the "other_config" column
452 * in the "QoS" table in vswitchd/vswitch.xml (which is built as
453 * ovs-vswitchd.conf.db(8)).
455 * May be NULL if 'netdev' does not support QoS at all. */
456 int (*set_qos)(struct netdev *netdev,
457 const char *type, const struct smap *details);
459 /* Queries 'netdev' for information about the queue numbered 'queue_id'.
460 * If successful, adds that information as string key-value pairs to
461 * 'details'. Returns 0 if successful, otherwise a positive errno value.
463 * Should return EINVAL if 'queue_id' is greater than or equal to the
464 * number of supported queues (as reported in the 'n_queues' member of
465 * struct netdev_qos_capabilities by 'get_qos_capabilities').
467 * The caller initializes 'details' before calling this function. The
468 * caller takes ownership of the string key-values pairs added to
471 * The returned contents of 'details' should be documented as valid for the
472 * given 'type' in the "other_config" column in the "Queue" table in
473 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
475 int (*get_queue)(const struct netdev *netdev,
476 unsigned int queue_id, struct smap *details);
478 /* Configures the queue numbered 'queue_id' on 'netdev' with the key-value
479 * string pairs in 'details'. The contents of 'details' should be
480 * documented as valid for the given 'type' in the "other_config" column in
481 * the "Queue" table in vswitchd/vswitch.xml (which is built as
482 * ovs-vswitchd.conf.db(8)). Returns 0 if successful, otherwise a positive
483 * errno value. On failure, the given queue's configuration should be
486 * Should return EINVAL if 'queue_id' is greater than or equal to the
487 * number of supported queues (as reported in the 'n_queues' member of
488 * struct netdev_qos_capabilities by 'get_qos_capabilities'), or if
489 * 'details' is invalid for the type of queue.
491 * This function does not modify 'details', and the caller retains
494 * May be NULL if 'netdev' does not support QoS at all. */
495 int (*set_queue)(struct netdev *netdev,
496 unsigned int queue_id, const struct smap *details);
498 /* Attempts to delete the queue numbered 'queue_id' from 'netdev'.
500 * Should return EINVAL if 'queue_id' is greater than or equal to the
501 * number of supported queues (as reported in the 'n_queues' member of
502 * struct netdev_qos_capabilities by 'get_qos_capabilities'). Should
503 * return EOPNOTSUPP if 'queue_id' is valid but may not be deleted (e.g. if
504 * 'netdev' has a fixed set of queues with the current QoS mode).
506 * May be NULL if 'netdev' does not support QoS at all, or if all of its
507 * QoS modes have fixed sets of queues. */
508 int (*delete_queue)(struct netdev *netdev, unsigned int queue_id);
510 /* Obtains statistics about 'queue_id' on 'netdev'. Fills 'stats' with the
511 * queue's statistics. May set individual members of 'stats' to all-1-bits
512 * if the statistic is unavailable.
514 * May be NULL if 'netdev' does not support QoS at all. */
515 int (*get_queue_stats)(const struct netdev *netdev, unsigned int queue_id,
516 struct netdev_queue_stats *stats);
518 /* Attempts to begin dumping the queues in 'netdev'. On success, returns 0
519 * and initializes '*statep' with any data needed for iteration. On
520 * failure, returns a positive errno value.
522 * May be NULL if 'netdev' does not support QoS at all. */
523 int (*queue_dump_start)(const struct netdev *netdev, void **statep);
525 /* Attempts to retrieve another queue from 'netdev' for 'state', which was
526 * initialized by a successful call to the 'queue_dump_start' function for
527 * 'netdev'. On success, stores a queue ID into '*queue_id' and fills
528 * 'details' with the configuration of the queue with that ID. Returns EOF
529 * if the last queue has been dumped, or a positive errno value on error.
530 * This function will not be called again once it returns nonzero once for
531 * a given iteration (but the 'queue_dump_done' function will be called
534 * The caller initializes and clears 'details' before calling this
535 * function. The caller takes ownership of the string key-values pairs
536 * added to 'details'.
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 * May be NULL if 'netdev' does not support QoS at all. */
543 int (*queue_dump_next)(const struct netdev *netdev, void *state,
544 unsigned int *queue_id, struct smap *details);
546 /* Releases resources from 'netdev' for 'state', which was initialized by a
547 * successful call to the 'queue_dump_start' function for 'netdev'.
549 * May be NULL if 'netdev' does not support QoS at all. */
550 int (*queue_dump_done)(const struct netdev *netdev, void *state);
552 /* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
553 * ID, its statistics, and the 'aux' specified by the caller. The order of
554 * iteration is unspecified, but (when successful) each queue must be
555 * visited exactly once.
557 * 'cb' will not modify or free the statistics passed in. */
558 int (*dump_queue_stats)(const struct netdev *netdev,
559 void (*cb)(unsigned int queue_id,
560 struct netdev_queue_stats *,
564 /* If 'netdev' has an assigned IPv4 address, sets '*address' to that
565 * address and '*netmask' to the associated netmask.
567 * The following error values have well-defined meanings:
569 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv4 address.
571 * - EOPNOTSUPP: No IPv4 network stack attached to 'netdev'.
573 * This function may be set to null if it would always return EOPNOTSUPP
575 int (*get_in4)(const struct netdev *netdev, struct in_addr *address,
576 struct in_addr *netmask);
578 /* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask. If
579 * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared.
581 * This function may be set to null if it would always return EOPNOTSUPP
583 int (*set_in4)(struct netdev *netdev, struct in_addr addr,
584 struct in_addr mask);
586 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address.
588 * The following error values have well-defined meanings:
590 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv6 address.
592 * - EOPNOTSUPP: No IPv6 network stack attached to 'netdev'.
594 * This function may be set to null if it would always return EOPNOTSUPP
596 int (*get_in6)(const struct netdev *netdev, struct in6_addr *in6);
598 /* Adds 'router' as a default IP gateway for the TCP/IP stack that
599 * corresponds to 'netdev'.
601 * This function may be set to null if it would always return EOPNOTSUPP
603 int (*add_router)(struct netdev *netdev, struct in_addr router);
605 /* Looks up the next hop for 'host'. If successful, stores the next hop
606 * gateway's address (0 if 'host' is on a directly connected network) in
607 * '*next_hop' and a copy of the name of the device to reach 'host' in
608 * '*netdev_name', and returns 0. The caller is responsible for freeing
609 * '*netdev_name' (by calling free()).
611 * This function may be set to null if it would always return EOPNOTSUPP
613 int (*get_next_hop)(const struct in_addr *host, struct in_addr *next_hop,
616 /* Retrieves driver information of the device.
618 * Populates 'smap' with key-value pairs representing the status of the
619 * device. 'smap' is a set of key-value string pairs representing netdev
620 * type specific information. For more information see
621 * ovs-vswitchd.conf.db(5).
623 * The caller is responsible for destroying 'smap' and its data.
625 * This function may be set to null if it would always return EOPNOTSUPP
627 int (*get_status)(const struct netdev *netdev, struct smap *smap);
629 /* Looks up the ARP table entry for 'ip' on 'netdev' and stores the
630 * corresponding MAC address in 'mac'. A return value of ENXIO, in
631 * particular, indicates that there is no ARP table entry for 'ip' on
634 * This function may be set to null if it would always return EOPNOTSUPP
636 int (*arp_lookup)(const struct netdev *netdev, ovs_be32 ip,
639 /* Retrieves the current set of flags on 'netdev' into '*old_flags'. Then,
640 * turns off the flags that are set to 1 in 'off' and turns on the flags
641 * that are set to 1 in 'on'. (No bit will be set to 1 in both 'off' and
642 * 'on'; that is, off & on == 0.)
644 * This function may be invoked from a signal handler. Therefore, it
645 * should not do anything that is not signal-safe (such as logging). */
646 int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
647 enum netdev_flags on, enum netdev_flags *old_flags);
649 /* ## -------------------- ## */
650 /* ## netdev_rxq Functions ## */
651 /* ## -------------------- ## */
653 /* If a particular netdev class does not support receiving packets, all these
654 * function pointers must be NULL. */
656 /* Life-cycle functions for a netdev_rxq. See the large comment above on
657 * struct netdev_class. */
658 struct netdev_rxq *(*rxq_alloc)(void);
659 int (*rxq_construct)(struct netdev_rxq *);
660 void (*rxq_destruct)(struct netdev_rxq *);
661 void (*rxq_dealloc)(struct netdev_rxq *);
663 /* Attempts to receive batch of packets from 'rx' and place array of pointers
664 * into '*pkt'. netdev is responsible for allocating buffers.
665 * '*cnt' points to packet count for given batch. Once packets are returned
666 * to caller, netdev should give up ownership of ofpbuf data.
668 * Implementations should allocate buffer with DP_NETDEV_HEADROOM headroom
669 * and add a VLAN header which is obtained out-of-band to the packet.
671 * Caller is expected to pass array of size MAX_RX_BATCH.
672 * This function may be set to null if it would always return EOPNOTSUPP
674 int (*rxq_recv)(struct netdev_rxq *rx, struct ofpbuf **pkt, int *cnt);
676 /* Registers with the poll loop to wake up from the next call to
677 * poll_block() when a packet is ready to be received with netdev_rxq_recv()
679 void (*rxq_wait)(struct netdev_rxq *rx);
681 /* Discards all packets waiting to be received from 'rx'. */
682 int (*rxq_drain)(struct netdev_rxq *rx);
685 int netdev_register_provider(const struct netdev_class *);
686 int netdev_unregister_provider(const char *type);
688 extern const struct netdev_class netdev_linux_class;
689 extern const struct netdev_class netdev_internal_class;
690 extern const struct netdev_class netdev_tap_class;
691 #if defined(__FreeBSD__) || defined(__NetBSD__)
692 extern const struct netdev_class netdev_bsd_class;
699 #endif /* netdev.h */