2 * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014 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"
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 /* The following are protected by 'netdev_mutex' (internal to netdev.c). */
58 int ref_cnt; /* Times this devices was opened. */
59 struct shash_node *node; /* Pointer to element in global map. */
60 struct ovs_list saved_flags_list; /* Contains "struct netdev_saved_flags". */
64 netdev_change_seq_changed(const struct netdev *netdev_)
66 struct netdev *netdev = CONST_CAST(struct netdev *, netdev_);
67 seq_change(connectivity_seq_get());
69 if (!netdev->change_seq) {
74 const char *netdev_get_type(const struct netdev *);
75 const struct netdev_class *netdev_get_class(const struct netdev *);
76 const char *netdev_get_name(const struct netdev *);
77 struct netdev *netdev_from_name(const char *name);
78 void netdev_get_devices(const struct netdev_class *,
79 struct shash *device_list);
80 struct netdev **netdev_get_vports(size_t *size);
82 /* A data structure for capturing packets received by a network device.
84 * Network device implementations may read these members but should not modify
87 * None of these members change during the lifetime of a struct netdev_rxq. */
89 struct netdev *netdev; /* Owns a reference to the netdev. */
93 struct netdev *netdev_rxq_get_netdev(const struct netdev_rxq *);
95 /* Network device class structure, to be defined by each implementation of a
98 * These functions return 0 if successful or a positive errno value on failure,
99 * except where otherwise noted.
105 * These functions work primarily with two different kinds of data structures:
107 * - "struct netdev", which represents a network device.
109 * - "struct netdev_rxq", which represents a handle for capturing packets
110 * received on a network device
112 * Each of these data structures contains all of the implementation-independent
113 * generic state for the respective concept, called the "base" state. None of
114 * them contains any extra space for implementations to use. Instead, each
115 * implementation is expected to declare its own data structure that contains
116 * an instance of the generic data structure plus additional
117 * implementation-specific members, called the "derived" state. The
118 * implementation can use casts or (preferably) the CONTAINER_OF macro to
119 * obtain access to derived state given only a pointer to the embedded generic
126 * Four stylized functions accompany each of these data structures:
128 * "alloc" "construct" "destruct" "dealloc"
129 * ------------ ---------------- --------------- --------------
130 * netdev ->alloc ->construct ->destruct ->dealloc
131 * netdev_rxq ->rxq_alloc ->rxq_construct ->rxq_destruct ->rxq_dealloc
133 * Any instance of a given data structure goes through the following life
136 * 1. The client calls the "alloc" function to obtain raw memory. If "alloc"
137 * fails, skip all the other steps.
139 * 2. The client initializes all of the data structure's base state. If this
140 * fails, skip to step 7.
142 * 3. The client calls the "construct" function. The implementation
143 * initializes derived state. It may refer to the already-initialized
144 * base state. If "construct" fails, skip to step 6.
146 * 4. The data structure is now initialized and in use.
148 * 5. When the data structure is no longer needed, the client calls the
149 * "destruct" function. The implementation uninitializes derived state.
150 * The base state has not been uninitialized yet, so the implementation
151 * may still refer to it.
153 * 6. The client uninitializes all of the data structure's base state.
155 * 7. The client calls the "dealloc" to free the raw memory. The
156 * implementation must not refer to base or derived state in the data
157 * structure, because it has already been uninitialized.
159 * If netdev support multi-queue IO then netdev->construct should set initialize
160 * netdev->n_rxq to number of queues.
162 * Each "alloc" function allocates and returns a new instance of the respective
163 * data structure. The "alloc" function is not given any information about the
164 * use of the new data structure, so it cannot perform much initialization.
165 * Its purpose is just to ensure that the new data structure has enough room
166 * for base and derived state. It may return a null pointer if memory is not
167 * available, in which case none of the other functions is called.
169 * Each "construct" function initializes derived state in its respective data
170 * structure. When "construct" is called, all of the base state has already
171 * been initialized, so the "construct" function may refer to it. The
172 * "construct" function is allowed to fail, in which case the client calls the
173 * "dealloc" function (but not the "destruct" function).
175 * Each "destruct" function uninitializes and frees derived state in its
176 * respective data structure. When "destruct" is called, the base state has
177 * not yet been uninitialized, so the "destruct" function may refer to it. The
178 * "destruct" function is not allowed to fail.
180 * Each "dealloc" function frees raw memory that was allocated by the the
181 * "alloc" function. The memory's base and derived members might not have ever
182 * been initialized (but if "construct" returned successfully, then it has been
183 * "destruct"ed already). The "dealloc" function is not allowed to fail.
186 * Device Change Notification
187 * ==========================
189 * Minimally, implementations are required to report changes to netdev flags,
190 * features, ethernet address or carrier through connectivity_seq. Changes to
191 * other properties are allowed to cause notification through this interface,
192 * although implementations should try to avoid this. connectivity_seq_get()
193 * can be used to acquire a reference to the struct seq. The interface is
194 * described in detail in seq.h. */
195 struct netdev_class {
196 /* Type of netdevs in this class, e.g. "system", "tap", "gre", etc.
198 * One of the providers should supply a "system" type, since this is
199 * the type assumed if no type is specified when opening a netdev.
200 * The "system" type corresponds to an existing network device on
204 /* ## ------------------- ## */
205 /* ## Top-Level Functions ## */
206 /* ## ------------------- ## */
208 /* Called when the netdev provider is registered, typically at program
209 * startup. Returning an error from this function will prevent any network
210 * device in this class from being opened.
212 * This function may be set to null if a network device class needs no
213 * initialization at registration time. */
216 /* Performs periodic work needed by netdevs of this class. May be null if
217 * no periodic work is necessary. */
220 /* Arranges for poll_block() to wake up if the "run" member function needs
221 * to be called. Implementations are additionally required to wake
222 * whenever something changes in any of its netdevs which would cause their
223 * ->change_seq() function to change its result. May be null if nothing is
227 /* ## ---------------- ## */
228 /* ## netdev Functions ## */
229 /* ## ---------------- ## */
231 /* Life-cycle functions for a netdev. See the large comment above on
232 * struct netdev_class. */
233 struct netdev *(*alloc)(void);
234 int (*construct)(struct netdev *);
235 void (*destruct)(struct netdev *);
236 void (*dealloc)(struct netdev *);
238 /* Fetches the device 'netdev''s configuration, storing it in 'args'.
239 * The caller owns 'args' and pre-initializes it to an empty smap.
241 * If this netdev class does not have any configuration options, this may
242 * be a null pointer. */
243 int (*get_config)(const struct netdev *netdev, struct smap *args);
245 /* Changes the device 'netdev''s configuration to 'args'.
247 * If this netdev class does not support configuration, this may be a null
249 int (*set_config)(struct netdev *netdev, const struct smap *args);
251 /* Returns the tunnel configuration of 'netdev'. If 'netdev' is
252 * not a tunnel, returns null.
254 * If this function would always return null, it may be null instead. */
255 const struct netdev_tunnel_config *
256 (*get_tunnel_config)(const struct netdev *netdev);
258 /* Build Partial Tunnel header. Ethernet and ip header is already built,
259 * build_header() is suppose build protocol specific part of header. */
260 int (*build_header)(const struct netdev *, struct ovs_action_push_tnl *data,
261 const struct flow *tnl_flow);
263 /* build_header() can not build entire header for all packets for given
264 * flow. Push header is called for packet to build header specific to
265 * a packet on actual transmit. It uses partial header build by
266 * build_header() which is passed as data. */
267 void (*push_header)(struct dp_packet *packet,
268 const struct ovs_action_push_tnl *data);
270 /* Pop tunnel header from packet, build tunnel metadata and resize packet
271 * for further processing. */
272 int (*pop_header)(struct dp_packet *packet);
274 /* Returns the id of the numa node the 'netdev' is on. If there is no
275 * such info, returns NETDEV_NUMA_UNSPEC. */
276 int (*get_numa_id)(const struct netdev *netdev);
278 /* Configures the number of tx queues and rx queues of 'netdev'.
279 * Return 0 if successful, otherwise a positive errno value.
281 * On error, the tx queue and rx queue configuration is indeterminant.
282 * Caller should make decision on whether to restore the previous or
283 * the default configuration. Also, caller must make sure there is no
284 * other thread accessing the queues at the same time. */
285 int (*set_multiq)(struct netdev *netdev, unsigned int n_txq,
288 /* Sends buffers on 'netdev'.
289 * Returns 0 if successful (for every buffer), otherwise a positive errno
290 * value. Returns EAGAIN without blocking if one or more packets cannot be
291 * queued immediately. Returns EMSGSIZE if a partial packet was transmitted
292 * or if a packet is too big or too small to transmit on the device.
294 * If the function returns a non-zero value, some of the packets might have
297 * To retain ownership of 'buffers' caller can set may_steal to false.
299 * The network device is expected to maintain one or more packet
300 * transmission queues, so that the caller does not ordinarily have to
301 * do additional queuing of packets. 'qid' specifies the queue to use
302 * and can be ignored if the implementation does not support multiple
305 * May return EOPNOTSUPP if a network device does not implement packet
306 * transmission through this interface. This function may be set to null
307 * if it would always return EOPNOTSUPP anyhow. (This will prevent the
308 * network device from being usefully used by the netdev-based "userspace
309 * datapath". It will also prevent the OVS implementation of bonding from
310 * working properly over 'netdev'.) */
311 int (*send)(struct netdev *netdev, int qid, struct dp_packet **buffers,
312 int cnt, bool may_steal);
314 /* Registers with the poll loop to wake up from the next call to
315 * poll_block() when the packet transmission queue for 'netdev' has
316 * sufficient room to transmit a packet with netdev_send().
318 * The network device is expected to maintain one or more packet
319 * transmission queues, so that the caller does not ordinarily have to
320 * do additional queuing of packets. 'qid' specifies the queue to use
321 * and can be ignored if the implementation does not support multiple
324 * May be null if not needed, such as for a network device that does not
325 * implement packet transmission through the 'send' member function. */
326 void (*send_wait)(struct netdev *netdev, int qid);
328 /* Sets 'netdev''s Ethernet address to 'mac' */
329 int (*set_etheraddr)(struct netdev *netdev,
330 const uint8_t mac[ETH_ADDR_LEN]);
332 /* Retrieves 'netdev''s Ethernet address into 'mac'.
334 * This address will be advertised as 'netdev''s MAC address through the
335 * OpenFlow protocol, among other uses. */
336 int (*get_etheraddr)(const struct netdev *netdev,
337 uint8_t mac[ETH_ADDR_LEN]);
339 /* Retrieves 'netdev''s MTU into '*mtup'.
341 * The MTU is the maximum size of transmitted (and received) packets, in
342 * bytes, not including the hardware header; thus, this is typically 1500
343 * bytes for Ethernet devices.
345 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
346 * this function should return EOPNOTSUPP. This function may be set to
347 * null if it would always return EOPNOTSUPP. */
348 int (*get_mtu)(const struct netdev *netdev, int *mtup);
350 /* Sets 'netdev''s MTU to 'mtu'.
352 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
353 * this function should return EOPNOTSUPP. This function may be set to
354 * null if it would always return EOPNOTSUPP. */
355 int (*set_mtu)(const struct netdev *netdev, int mtu);
357 /* Returns the ifindex of 'netdev', if successful, as a positive number.
358 * On failure, returns a negative errno value.
360 * The desired semantics of the ifindex value are a combination of those
361 * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An
362 * ifindex value should be unique within a host and remain stable at least
363 * until reboot. SNMP says an ifindex "ranges between 1 and the value of
364 * ifNumber" but many systems do not follow this rule anyhow.
366 * This function may be set to null if it would always return -EOPNOTSUPP.
368 int (*get_ifindex)(const struct netdev *netdev);
370 /* Sets 'carrier' to true if carrier is active (link light is on) on
373 * May be null if device does not provide carrier status (will be always
374 * up as long as device is up).
376 int (*get_carrier)(const struct netdev *netdev, bool *carrier);
378 /* Returns the number of times 'netdev''s carrier has changed since being
381 * If null, callers will assume the number of carrier resets is zero. */
382 long long int (*get_carrier_resets)(const struct netdev *netdev);
384 /* Forces ->get_carrier() to poll 'netdev''s MII registers for link status
385 * instead of checking 'netdev''s carrier. 'netdev''s MII registers will
386 * be polled once every 'interval' milliseconds. If 'netdev' does not
387 * support MII, another method may be used as a fallback. If 'interval' is
388 * less than or equal to zero, reverts ->get_carrier() to its normal
391 * Most network devices won't support this feature and will set this
392 * function pointer to NULL, which is equivalent to returning EOPNOTSUPP.
394 int (*set_miimon_interval)(struct netdev *netdev, long long int interval);
396 /* Retrieves current device stats for 'netdev' into 'stats'.
398 * A network device that supports some statistics but not others, it should
399 * set the values of the unsupported statistics to all-1-bits
401 int (*get_stats)(const struct netdev *netdev, struct netdev_stats *);
403 /* Stores the features supported by 'netdev' into each of '*current',
404 * '*advertised', '*supported', and '*peer'. Each value is a bitmap of
407 * This function may be set to null if it would always return EOPNOTSUPP.
409 int (*get_features)(const struct netdev *netdev,
410 enum netdev_features *current,
411 enum netdev_features *advertised,
412 enum netdev_features *supported,
413 enum netdev_features *peer);
415 /* Set the features advertised by 'netdev' to 'advertise', which is a
416 * set of NETDEV_F_* bits.
418 * This function may be set to null for a network device that does not
419 * support configuring advertisements. */
420 int (*set_advertisements)(struct netdev *netdev,
421 enum netdev_features advertise);
423 /* Attempts to set input rate limiting (policing) policy, such that up to
424 * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative
425 * burst size of 'kbits' kb.
427 * This function may be set to null if policing is not supported. */
428 int (*set_policing)(struct netdev *netdev, unsigned int kbits_rate,
429 unsigned int kbits_burst);
431 /* Adds to 'types' all of the forms of QoS supported by 'netdev', or leaves
432 * it empty if 'netdev' does not support QoS. Any names added to 'types'
433 * should be documented as valid for the "type" column in the "QoS" table
434 * in vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
436 * Every network device must support disabling QoS with a type of "", but
437 * this function must not add "" to 'types'.
439 * The caller is responsible for initializing 'types' (e.g. with
440 * sset_init()) before calling this function. The caller retains ownership
443 * May be NULL if 'netdev' does not support QoS at all. */
444 int (*get_qos_types)(const struct netdev *netdev, struct sset *types);
446 /* Queries 'netdev' for its capabilities regarding the specified 'type' of
447 * QoS. On success, initializes 'caps' with the QoS capabilities.
449 * Should return EOPNOTSUPP if 'netdev' does not support 'type'. May be
450 * NULL if 'netdev' does not support QoS at all. */
451 int (*get_qos_capabilities)(const struct netdev *netdev,
453 struct netdev_qos_capabilities *caps);
455 /* Queries 'netdev' about its currently configured form of QoS. If
456 * successful, stores the name of the current form of QoS into '*typep'
457 * and any details of configuration as string key-value pairs in
460 * A '*typep' of "" indicates that QoS is currently disabled on 'netdev'.
462 * The caller initializes 'details' before calling this function. The
463 * caller takes ownership of the string key-values pairs added to
466 * The netdev retains ownership of '*typep'.
468 * '*typep' will be one of the types returned by netdev_get_qos_types() for
469 * 'netdev'. The contents of 'details' should be documented as valid for
470 * '*typep' in the "other_config" column in the "QoS" table in
471 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
473 * May be NULL if 'netdev' does not support QoS at all. */
474 int (*get_qos)(const struct netdev *netdev,
475 const char **typep, struct smap *details);
477 /* Attempts to reconfigure QoS on 'netdev', changing the form of QoS to
478 * 'type' with details of configuration from 'details'.
480 * On error, the previous QoS configuration is retained.
482 * When this function changes the type of QoS (not just 'details'), this
483 * also resets all queue configuration for 'netdev' to their defaults
484 * (which depend on the specific type of QoS). Otherwise, the queue
485 * configuration for 'netdev' is unchanged.
487 * 'type' should be "" (to disable QoS) or one of the types returned by
488 * netdev_get_qos_types() for 'netdev'. The contents of 'details' should
489 * be documented as valid for the given 'type' in the "other_config" column
490 * in the "QoS" table in vswitchd/vswitch.xml (which is built as
491 * ovs-vswitchd.conf.db(8)).
493 * May be NULL if 'netdev' does not support QoS at all. */
494 int (*set_qos)(struct netdev *netdev,
495 const char *type, const struct smap *details);
497 /* Queries 'netdev' for information about the queue numbered 'queue_id'.
498 * If successful, adds that information as string key-value pairs to
499 * 'details'. Returns 0 if successful, otherwise a positive errno value.
501 * Should return EINVAL if 'queue_id' is greater than or equal to the
502 * number of supported queues (as reported in the 'n_queues' member of
503 * struct netdev_qos_capabilities by 'get_qos_capabilities').
505 * The caller initializes 'details' before calling this function. The
506 * caller takes ownership of the string key-values pairs added to
509 * The returned contents of 'details' should be documented as valid for the
510 * given 'type' in the "other_config" column in the "Queue" table in
511 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
513 int (*get_queue)(const struct netdev *netdev,
514 unsigned int queue_id, struct smap *details);
516 /* Configures the queue numbered 'queue_id' on 'netdev' with the key-value
517 * string pairs in 'details'. The contents of 'details' should be
518 * documented as valid for the given 'type' in the "other_config" column in
519 * the "Queue" table in vswitchd/vswitch.xml (which is built as
520 * ovs-vswitchd.conf.db(8)). Returns 0 if successful, otherwise a positive
521 * errno value. On failure, the given queue's configuration should be
524 * Should return EINVAL if 'queue_id' is greater than or equal to the
525 * number of supported queues (as reported in the 'n_queues' member of
526 * struct netdev_qos_capabilities by 'get_qos_capabilities'), or if
527 * 'details' is invalid for the type of queue.
529 * This function does not modify 'details', and the caller retains
532 * May be NULL if 'netdev' does not support QoS at all. */
533 int (*set_queue)(struct netdev *netdev,
534 unsigned int queue_id, const struct smap *details);
536 /* Attempts to delete the queue numbered 'queue_id' from 'netdev'.
538 * Should return EINVAL if 'queue_id' is greater than or equal to the
539 * number of supported queues (as reported in the 'n_queues' member of
540 * struct netdev_qos_capabilities by 'get_qos_capabilities'). Should
541 * return EOPNOTSUPP if 'queue_id' is valid but may not be deleted (e.g. if
542 * 'netdev' has a fixed set of queues with the current QoS mode).
544 * May be NULL if 'netdev' does not support QoS at all, or if all of its
545 * QoS modes have fixed sets of queues. */
546 int (*delete_queue)(struct netdev *netdev, unsigned int queue_id);
548 /* Obtains statistics about 'queue_id' on 'netdev'. Fills 'stats' with the
549 * queue's statistics. May set individual members of 'stats' to all-1-bits
550 * if the statistic is unavailable.
552 * May be NULL if 'netdev' does not support QoS at all. */
553 int (*get_queue_stats)(const struct netdev *netdev, unsigned int queue_id,
554 struct netdev_queue_stats *stats);
556 /* Attempts to begin dumping the queues in 'netdev'. On success, returns 0
557 * and initializes '*statep' with any data needed for iteration. On
558 * failure, returns a positive errno value.
560 * May be NULL if 'netdev' does not support QoS at all. */
561 int (*queue_dump_start)(const struct netdev *netdev, void **statep);
563 /* Attempts to retrieve another queue from 'netdev' for 'state', which was
564 * initialized by a successful call to the 'queue_dump_start' function for
565 * 'netdev'. On success, stores a queue ID into '*queue_id' and fills
566 * 'details' with the configuration of the queue with that ID. Returns EOF
567 * if the last queue has been dumped, or a positive errno value on error.
568 * This function will not be called again once it returns nonzero once for
569 * a given iteration (but the 'queue_dump_done' function will be called
572 * The caller initializes and clears 'details' before calling this
573 * function. The caller takes ownership of the string key-values pairs
574 * added to 'details'.
576 * The returned contents of 'details' should be documented as valid for the
577 * given 'type' in the "other_config" column in the "Queue" table in
578 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
580 * May be NULL if 'netdev' does not support QoS at all. */
581 int (*queue_dump_next)(const struct netdev *netdev, void *state,
582 unsigned int *queue_id, struct smap *details);
584 /* Releases resources from 'netdev' for 'state', which was initialized by a
585 * successful call to the 'queue_dump_start' function for 'netdev'.
587 * May be NULL if 'netdev' does not support QoS at all. */
588 int (*queue_dump_done)(const struct netdev *netdev, void *state);
590 /* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
591 * ID, its statistics, and the 'aux' specified by the caller. The order of
592 * iteration is unspecified, but (when successful) each queue must be
593 * visited exactly once.
595 * 'cb' will not modify or free the statistics passed in. */
596 int (*dump_queue_stats)(const struct netdev *netdev,
597 void (*cb)(unsigned int queue_id,
598 struct netdev_queue_stats *,
602 /* If 'netdev' has an assigned IPv4 address, sets '*address' to that
603 * address and '*netmask' to the associated netmask.
605 * The following error values have well-defined meanings:
607 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv4 address.
609 * - EOPNOTSUPP: No IPv4 network stack attached to 'netdev'.
611 * This function may be set to null if it would always return EOPNOTSUPP
613 int (*get_in4)(const struct netdev *netdev, struct in_addr *address,
614 struct in_addr *netmask);
616 /* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask. If
617 * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared.
619 * This function may be set to null if it would always return EOPNOTSUPP
621 int (*set_in4)(struct netdev *netdev, struct in_addr addr,
622 struct in_addr mask);
624 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address.
626 * The following error values have well-defined meanings:
628 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv6 address.
630 * - EOPNOTSUPP: No IPv6 network stack attached to 'netdev'.
632 * This function may be set to null if it would always return EOPNOTSUPP
634 int (*get_in6)(const struct netdev *netdev, struct in6_addr *in6);
636 /* Adds 'router' as a default IP gateway for the TCP/IP stack that
637 * corresponds to 'netdev'.
639 * This function may be set to null if it would always return EOPNOTSUPP
641 int (*add_router)(struct netdev *netdev, struct in_addr router);
643 /* Looks up the next hop for 'host' in the host's routing table. If
644 * successful, stores the next hop gateway's address (0 if 'host' is on a
645 * directly connected network) in '*next_hop' and a copy of the name of the
646 * device to reach 'host' in '*netdev_name', and returns 0. The caller is
647 * responsible for freeing '*netdev_name' (by calling free()).
649 * This function may be set to null if it would always return EOPNOTSUPP
651 int (*get_next_hop)(const struct in_addr *host, struct in_addr *next_hop,
654 /* Retrieves driver information of the device.
656 * Populates 'smap' with key-value pairs representing the status of the
657 * device. 'smap' is a set of key-value string pairs representing netdev
658 * type specific information. For more information see
659 * ovs-vswitchd.conf.db(5).
661 * The caller is responsible for destroying 'smap' and its data.
663 * This function may be set to null if it would always return EOPNOTSUPP
665 int (*get_status)(const struct netdev *netdev, struct smap *smap);
667 /* Looks up the ARP table entry for 'ip' on 'netdev' and stores the
668 * corresponding MAC address in 'mac'. A return value of ENXIO, in
669 * particular, indicates that there is no ARP table entry for 'ip' on
672 * This function may be set to null if it would always return EOPNOTSUPP
674 int (*arp_lookup)(const struct netdev *netdev, ovs_be32 ip,
675 uint8_t mac[ETH_ADDR_LEN]);
677 /* Retrieves the current set of flags on 'netdev' into '*old_flags'. Then,
678 * turns off the flags that are set to 1 in 'off' and turns on the flags
679 * that are set to 1 in 'on'. (No bit will be set to 1 in both 'off' and
680 * 'on'; that is, off & on == 0.)
682 * This function may be invoked from a signal handler. Therefore, it
683 * should not do anything that is not signal-safe (such as logging). */
684 int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
685 enum netdev_flags on, enum netdev_flags *old_flags);
687 /* ## -------------------- ## */
688 /* ## netdev_rxq Functions ## */
689 /* ## -------------------- ## */
691 /* If a particular netdev class does not support receiving packets, all these
692 * function pointers must be NULL. */
694 /* Life-cycle functions for a netdev_rxq. See the large comment above on
695 * struct netdev_class. */
696 struct netdev_rxq *(*rxq_alloc)(void);
697 int (*rxq_construct)(struct netdev_rxq *);
698 void (*rxq_destruct)(struct netdev_rxq *);
699 void (*rxq_dealloc)(struct netdev_rxq *);
701 /* Attempts to receive batch of packets from 'rx' and place array of
702 * pointers into '*pkts'. netdev is responsible for allocating buffers.
703 * '*cnt' points to packet count for given batch. Once packets are returned
704 * to caller, netdev should give up ownership of ofpbuf data.
706 * Implementations should allocate buffer with DP_NETDEV_HEADROOM headroom
707 * and add a VLAN header which is obtained out-of-band to the packet.
709 * Caller is expected to pass array of size MAX_RX_BATCH.
710 * This function may be set to null if it would always return EOPNOTSUPP
712 int (*rxq_recv)(struct netdev_rxq *rx, struct dp_packet **pkts,
715 /* Registers with the poll loop to wake up from the next call to
716 * poll_block() when a packet is ready to be received with netdev_rxq_recv()
718 void (*rxq_wait)(struct netdev_rxq *rx);
720 /* Discards all packets waiting to be received from 'rx'. */
721 int (*rxq_drain)(struct netdev_rxq *rx);
724 int netdev_register_provider(const struct netdev_class *);
725 int netdev_unregister_provider(const char *type);
727 #if defined(__FreeBSD__) || defined(__NetBSD__)
728 extern const struct netdev_class netdev_bsd_class;
729 #elif defined(_WIN32)
730 extern const struct netdev_class netdev_windows_class;
732 extern const struct netdev_class netdev_linux_class;
734 extern const struct netdev_class netdev_internal_class;
735 extern const struct netdev_class netdev_tap_class;
741 #endif /* netdev.h */