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"
28 #include "openvswitch/shash.h"
35 struct netdev_tnl_build_header_params;
36 #define NETDEV_NUMA_UNSPEC OVS_NUMA_UNSPEC
38 /* A network device (e.g. an Ethernet device).
40 * Network device implementations may read these members but should not modify
43 /* The following do not change during the lifetime of a struct netdev. */
44 char *name; /* Name of network device. */
45 const struct netdev_class *netdev_class; /* Functions to control
48 /* A sequence number which indicates changes in one of 'netdev''s
49 * properties. It must be nonzero so that users have a value which
50 * they may use as a reset when tracking 'netdev'.
52 * Minimally, the sequence number is required to change whenever
53 * 'netdev''s flags, features, ethernet address, or carrier changes. */
56 /* A netdev provider might be unable to change some of the device's
57 * parameter (n_rxq, mtu) when the device is in use. In this case
58 * the provider can notify the upper layer by calling
59 * netdev_request_reconfigure(). The upper layer will react by stopping
60 * the operations on the device and calling netdev_reconfigure() to allow
61 * the configuration changes. 'last_reconfigure_seq' remembers the value
62 * of 'reconfigure_seq' when the last reconfiguration happened. */
63 struct seq *reconfigure_seq;
64 uint64_t last_reconfigure_seq;
66 /* The core netdev code initializes these at netdev construction and only
67 * provide read-only access to its client. Netdev implementations may
71 int ref_cnt; /* Times this devices was opened. */
72 struct shash_node *node; /* Pointer to element in global map. */
73 struct ovs_list saved_flags_list; /* Contains "struct netdev_saved_flags". */
77 netdev_change_seq_changed(const struct netdev *netdev_)
79 struct netdev *netdev = CONST_CAST(struct netdev *, netdev_);
80 seq_change(connectivity_seq_get());
82 if (!netdev->change_seq) {
88 netdev_request_reconfigure(struct netdev *netdev)
90 seq_change(netdev->reconfigure_seq);
93 const char *netdev_get_type(const struct netdev *);
94 const struct netdev_class *netdev_get_class(const struct netdev *);
95 const char *netdev_get_name(const struct netdev *);
96 struct netdev *netdev_from_name(const char *name);
97 void netdev_get_devices(const struct netdev_class *,
98 struct shash *device_list);
99 struct netdev **netdev_get_vports(size_t *size);
101 /* A data structure for capturing packets received by a network device.
103 * Network device implementations may read these members but should not modify
106 * None of these members change during the lifetime of a struct netdev_rxq. */
108 struct netdev *netdev; /* Owns a reference to the netdev. */
112 struct netdev *netdev_rxq_get_netdev(const struct netdev_rxq *);
114 /* Network device class structure, to be defined by each implementation of a
117 * These functions return 0 if successful or a positive errno value on failure,
118 * except where otherwise noted.
124 * These functions work primarily with two different kinds of data structures:
126 * - "struct netdev", which represents a network device.
128 * - "struct netdev_rxq", which represents a handle for capturing packets
129 * received on a network device
131 * Each of these data structures contains all of the implementation-independent
132 * generic state for the respective concept, called the "base" state. None of
133 * them contains any extra space for implementations to use. Instead, each
134 * implementation is expected to declare its own data structure that contains
135 * an instance of the generic data structure plus additional
136 * implementation-specific members, called the "derived" state. The
137 * implementation can use casts or (preferably) the CONTAINER_OF macro to
138 * obtain access to derived state given only a pointer to the embedded generic
145 * Four stylized functions accompany each of these data structures:
147 * "alloc" "construct" "destruct" "dealloc"
148 * ------------ ---------------- --------------- --------------
149 * netdev ->alloc ->construct ->destruct ->dealloc
150 * netdev_rxq ->rxq_alloc ->rxq_construct ->rxq_destruct ->rxq_dealloc
152 * Any instance of a given data structure goes through the following life
155 * 1. The client calls the "alloc" function to obtain raw memory. If "alloc"
156 * fails, skip all the other steps.
158 * 2. The client initializes all of the data structure's base state. If this
159 * fails, skip to step 7.
161 * 3. The client calls the "construct" function. The implementation
162 * initializes derived state. It may refer to the already-initialized
163 * base state. If "construct" fails, skip to step 6.
165 * 4. The data structure is now initialized and in use.
167 * 5. When the data structure is no longer needed, the client calls the
168 * "destruct" function. The implementation uninitializes derived state.
169 * The base state has not been uninitialized yet, so the implementation
170 * may still refer to it.
172 * 6. The client uninitializes all of the data structure's base state.
174 * 7. The client calls the "dealloc" to free the raw memory. The
175 * implementation must not refer to base or derived state in the data
176 * structure, because it has already been uninitialized.
178 * If netdev support multi-queue IO then netdev->construct should set initialize
179 * netdev->n_rxq to number of queues.
181 * Each "alloc" function allocates and returns a new instance of the respective
182 * data structure. The "alloc" function is not given any information about the
183 * use of the new data structure, so it cannot perform much initialization.
184 * Its purpose is just to ensure that the new data structure has enough room
185 * for base and derived state. It may return a null pointer if memory is not
186 * available, in which case none of the other functions is called.
188 * Each "construct" function initializes derived state in its respective data
189 * structure. When "construct" is called, all of the base state has already
190 * been initialized, so the "construct" function may refer to it. The
191 * "construct" function is allowed to fail, in which case the client calls the
192 * "dealloc" function (but not the "destruct" function).
194 * Each "destruct" function uninitializes and frees derived state in its
195 * respective data structure. When "destruct" is called, the base state has
196 * not yet been uninitialized, so the "destruct" function may refer to it. The
197 * "destruct" function is not allowed to fail.
199 * Each "dealloc" function frees raw memory that was allocated by the
200 * "alloc" function. The memory's base and derived members might not have ever
201 * been initialized (but if "construct" returned successfully, then it has been
202 * "destruct"ed already). The "dealloc" function is not allowed to fail.
205 * Device Change Notification
206 * ==========================
208 * Minimally, implementations are required to report changes to netdev flags,
209 * features, ethernet address or carrier through connectivity_seq. Changes to
210 * other properties are allowed to cause notification through this interface,
211 * although implementations should try to avoid this. connectivity_seq_get()
212 * can be used to acquire a reference to the struct seq. The interface is
213 * described in detail in seq.h. */
214 struct netdev_class {
215 /* Type of netdevs in this class, e.g. "system", "tap", "gre", etc.
217 * One of the providers should supply a "system" type, since this is
218 * the type assumed if no type is specified when opening a netdev.
219 * The "system" type corresponds to an existing network device on
223 /* If 'true' then this netdev should be polled by PMD threads. */
226 /* ## ------------------- ## */
227 /* ## Top-Level Functions ## */
228 /* ## ------------------- ## */
230 /* Called when the netdev provider is registered, typically at program
231 * startup. Returning an error from this function will prevent any network
232 * device in this class from being opened.
234 * This function may be set to null if a network device class needs no
235 * initialization at registration time. */
238 /* Performs periodic work needed by netdevs of this class. May be null if
239 * no periodic work is necessary. */
242 /* Arranges for poll_block() to wake up if the "run" member function needs
243 * to be called. Implementations are additionally required to wake
244 * whenever something changes in any of its netdevs which would cause their
245 * ->change_seq() function to change its result. May be null if nothing is
249 /* ## ---------------- ## */
250 /* ## netdev Functions ## */
251 /* ## ---------------- ## */
253 /* Life-cycle functions for a netdev. See the large comment above on
254 * struct netdev_class. */
255 struct netdev *(*alloc)(void);
256 int (*construct)(struct netdev *);
257 void (*destruct)(struct netdev *);
258 void (*dealloc)(struct netdev *);
260 /* Fetches the device 'netdev''s configuration, storing it in 'args'.
261 * The caller owns 'args' and pre-initializes it to an empty smap.
263 * If this netdev class does not have any configuration options, this may
264 * be a null pointer. */
265 int (*get_config)(const struct netdev *netdev, struct smap *args);
267 /* Changes the device 'netdev''s configuration to 'args'.
269 * If this netdev class does not support configuration, this may be a null
271 int (*set_config)(struct netdev *netdev, const struct smap *args);
273 /* Returns the tunnel configuration of 'netdev'. If 'netdev' is
274 * not a tunnel, returns null.
276 * If this function would always return null, it may be null instead. */
277 const struct netdev_tunnel_config *
278 (*get_tunnel_config)(const struct netdev *netdev);
280 /* Build Tunnel header. Ethernet and ip header parameters are passed to
281 * tunnel implementation to build entire outer header for given flow. */
282 int (*build_header)(const struct netdev *, struct ovs_action_push_tnl *data,
283 const struct netdev_tnl_build_header_params *params);
285 /* build_header() can not build entire header for all packets for given
286 * flow. Push header is called for packet to build header specific to
287 * a packet on actual transmit. It uses partial header build by
288 * build_header() which is passed as data. */
289 void (*push_header)(struct dp_packet *packet,
290 const struct ovs_action_push_tnl *data);
292 /* Pop tunnel header from packet, build tunnel metadata and resize packet
293 * for further processing.
294 * Returns NULL in case of error or tunnel implementation queued packet for further
296 struct dp_packet * (*pop_header)(struct dp_packet *packet);
298 /* Returns the id of the numa node the 'netdev' is on. If there is no
299 * such info, returns NETDEV_NUMA_UNSPEC. */
300 int (*get_numa_id)(const struct netdev *netdev);
302 /* Configures the number of tx queues of 'netdev'. Returns 0 if successful,
303 * otherwise a positive errno value.
305 * 'n_txq' specifies the exact number of transmission queues to create.
306 * The caller will call netdev_send() concurrently from 'n_txq' different
307 * threads (with different qid). The netdev provider is responsible for
308 * making sure that these concurrent calls do not create a race condition
309 * by using multiple hw queues or locking.
311 * The caller will call netdev_reconfigure() (if necessary) before using
312 * netdev_send() on any of the newly configured queues, giving the provider
313 * a chance to adjust its settings.
315 * On error, the tx queue configuration is unchanged. */
316 int (*set_tx_multiq)(struct netdev *netdev, unsigned int n_txq);
318 /* Sends buffers on 'netdev'.
319 * Returns 0 if successful (for every buffer), otherwise a positive errno
320 * value. Returns EAGAIN without blocking if one or more packets cannot be
321 * queued immediately. Returns EMSGSIZE if a partial packet was transmitted
322 * or if a packet is too big or too small to transmit on the device.
324 * If the function returns a non-zero value, some of the packets might have
327 * If 'may_steal' is false, the caller retains ownership of all the
328 * packets. If 'may_steal' is true, the caller transfers ownership of all
329 * the packets to the network device, regardless of success.
331 * The network device is expected to maintain one or more packet
332 * transmission queues, so that the caller does not ordinarily have to
333 * do additional queuing of packets. 'qid' specifies the queue to use
334 * and can be ignored if the implementation does not support multiple
337 * May return EOPNOTSUPP if a network device does not implement packet
338 * transmission through this interface. This function may be set to null
339 * if it would always return EOPNOTSUPP anyhow. (This will prevent the
340 * network device from being usefully used by the netdev-based "userspace
341 * datapath". It will also prevent the OVS implementation of bonding from
342 * working properly over 'netdev'.) */
343 int (*send)(struct netdev *netdev, int qid, struct dp_packet_batch *batch,
346 /* Registers with the poll loop to wake up from the next call to
347 * poll_block() when the packet transmission queue for 'netdev' has
348 * sufficient room to transmit a packet with netdev_send().
350 * The network device is expected to maintain one or more packet
351 * transmission queues, so that the caller does not ordinarily have to
352 * do additional queuing of packets. 'qid' specifies the queue to use
353 * and can be ignored if the implementation does not support multiple
356 * May be null if not needed, such as for a network device that does not
357 * implement packet transmission through the 'send' member function. */
358 void (*send_wait)(struct netdev *netdev, int qid);
360 /* Sets 'netdev''s Ethernet address to 'mac' */
361 int (*set_etheraddr)(struct netdev *netdev, const struct eth_addr mac);
363 /* Retrieves 'netdev''s Ethernet address into 'mac'.
365 * This address will be advertised as 'netdev''s MAC address through the
366 * OpenFlow protocol, among other uses. */
367 int (*get_etheraddr)(const struct netdev *netdev, struct eth_addr *mac);
369 /* Retrieves 'netdev''s MTU into '*mtup'.
371 * The MTU is the maximum size of transmitted (and received) packets, in
372 * bytes, not including the hardware header; thus, this is typically 1500
373 * bytes for Ethernet devices.
375 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
376 * this function should return EOPNOTSUPP. This function may be set to
377 * null if it would always return EOPNOTSUPP. */
378 int (*get_mtu)(const struct netdev *netdev, int *mtup);
380 /* Sets 'netdev''s MTU to 'mtu'.
382 * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
383 * this function should return EOPNOTSUPP. This function may be set to
384 * null if it would always return EOPNOTSUPP. */
385 int (*set_mtu)(const struct netdev *netdev, int mtu);
387 /* Returns the ifindex of 'netdev', if successful, as a positive number.
388 * On failure, returns a negative errno value.
390 * The desired semantics of the ifindex value are a combination of those
391 * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An
392 * ifindex value should be unique within a host and remain stable at least
393 * until reboot. SNMP says an ifindex "ranges between 1 and the value of
394 * ifNumber" but many systems do not follow this rule anyhow.
396 * This function may be set to null if it would always return -EOPNOTSUPP.
398 int (*get_ifindex)(const struct netdev *netdev);
400 /* Sets 'carrier' to true if carrier is active (link light is on) on
403 * May be null if device does not provide carrier status (will be always
404 * up as long as device is up).
406 int (*get_carrier)(const struct netdev *netdev, bool *carrier);
408 /* Returns the number of times 'netdev''s carrier has changed since being
411 * If null, callers will assume the number of carrier resets is zero. */
412 long long int (*get_carrier_resets)(const struct netdev *netdev);
414 /* Forces ->get_carrier() to poll 'netdev''s MII registers for link status
415 * instead of checking 'netdev''s carrier. 'netdev''s MII registers will
416 * be polled once every 'interval' milliseconds. If 'netdev' does not
417 * support MII, another method may be used as a fallback. If 'interval' is
418 * less than or equal to zero, reverts ->get_carrier() to its normal
421 * Most network devices won't support this feature and will set this
422 * function pointer to NULL, which is equivalent to returning EOPNOTSUPP.
424 int (*set_miimon_interval)(struct netdev *netdev, long long int interval);
426 /* Retrieves current device stats for 'netdev' into 'stats'.
428 * A network device that supports some statistics but not others, it should
429 * set the values of the unsupported statistics to all-1-bits
431 int (*get_stats)(const struct netdev *netdev, struct netdev_stats *);
433 /* Stores the features supported by 'netdev' into each of '*current',
434 * '*advertised', '*supported', and '*peer'. Each value is a bitmap of
437 * This function may be set to null if it would always return EOPNOTSUPP.
439 int (*get_features)(const struct netdev *netdev,
440 enum netdev_features *current,
441 enum netdev_features *advertised,
442 enum netdev_features *supported,
443 enum netdev_features *peer);
445 /* Set the features advertised by 'netdev' to 'advertise', which is a
446 * set of NETDEV_F_* bits.
448 * This function may be set to null for a network device that does not
449 * support configuring advertisements. */
450 int (*set_advertisements)(struct netdev *netdev,
451 enum netdev_features advertise);
453 /* Attempts to set input rate limiting (policing) policy, such that up to
454 * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative
455 * burst size of 'kbits' kb.
457 * This function may be set to null if policing is not supported. */
458 int (*set_policing)(struct netdev *netdev, unsigned int kbits_rate,
459 unsigned int kbits_burst);
461 /* Adds to 'types' all of the forms of QoS supported by 'netdev', or leaves
462 * it empty if 'netdev' does not support QoS. Any names added to 'types'
463 * should be documented as valid for the "type" column in the "QoS" table
464 * in vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
466 * Every network device must support disabling QoS with a type of "", but
467 * this function must not add "" to 'types'.
469 * The caller is responsible for initializing 'types' (e.g. with
470 * sset_init()) before calling this function. The caller retains ownership
473 * May be NULL if 'netdev' does not support QoS at all. */
474 int (*get_qos_types)(const struct netdev *netdev, struct sset *types);
476 /* Queries 'netdev' for its capabilities regarding the specified 'type' of
477 * QoS. On success, initializes 'caps' with the QoS capabilities.
479 * Should return EOPNOTSUPP if 'netdev' does not support 'type'. May be
480 * NULL if 'netdev' does not support QoS at all. */
481 int (*get_qos_capabilities)(const struct netdev *netdev,
483 struct netdev_qos_capabilities *caps);
485 /* Queries 'netdev' about its currently configured form of QoS. If
486 * successful, stores the name of the current form of QoS into '*typep'
487 * and any details of configuration as string key-value pairs in
490 * A '*typep' of "" indicates that QoS is currently disabled on 'netdev'.
492 * The caller initializes 'details' before calling this function. The
493 * caller takes ownership of the string key-values pairs added to
496 * The netdev retains ownership of '*typep'.
498 * '*typep' will be one of the types returned by netdev_get_qos_types() for
499 * 'netdev'. The contents of 'details' should be documented as valid for
500 * '*typep' in the "other_config" column in the "QoS" table in
501 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
503 * May be NULL if 'netdev' does not support QoS at all. */
504 int (*get_qos)(const struct netdev *netdev,
505 const char **typep, struct smap *details);
507 /* Attempts to reconfigure QoS on 'netdev', changing the form of QoS to
508 * 'type' with details of configuration from 'details'.
510 * On error, the previous QoS configuration is retained.
512 * When this function changes the type of QoS (not just 'details'), this
513 * also resets all queue configuration for 'netdev' to their defaults
514 * (which depend on the specific type of QoS). Otherwise, the queue
515 * configuration for 'netdev' is unchanged.
517 * 'type' should be "" (to disable QoS) or one of the types returned by
518 * netdev_get_qos_types() for 'netdev'. The contents of 'details' should
519 * be documented as valid for the given 'type' in the "other_config" column
520 * in the "QoS" table in vswitchd/vswitch.xml (which is built as
521 * ovs-vswitchd.conf.db(8)).
523 * May be NULL if 'netdev' does not support QoS at all. */
524 int (*set_qos)(struct netdev *netdev,
525 const char *type, const struct smap *details);
527 /* Queries 'netdev' for information about the queue numbered 'queue_id'.
528 * If successful, adds that information as string key-value pairs to
529 * 'details'. Returns 0 if successful, otherwise a positive errno value.
531 * Should return EINVAL if 'queue_id' is greater than or equal to the
532 * number of supported queues (as reported in the 'n_queues' member of
533 * struct netdev_qos_capabilities by 'get_qos_capabilities').
535 * The caller initializes 'details' before calling this function. The
536 * caller takes ownership of the string key-values pairs added to
539 * The returned contents of 'details' should be documented as valid for the
540 * given 'type' in the "other_config" column in the "Queue" table in
541 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
543 int (*get_queue)(const struct netdev *netdev,
544 unsigned int queue_id, struct smap *details);
546 /* Configures the queue numbered 'queue_id' on 'netdev' with the key-value
547 * string pairs in 'details'. The contents of 'details' should be
548 * documented as valid for the given 'type' in the "other_config" column in
549 * the "Queue" table in vswitchd/vswitch.xml (which is built as
550 * ovs-vswitchd.conf.db(8)). Returns 0 if successful, otherwise a positive
551 * errno value. On failure, the given queue's configuration should be
554 * Should return EINVAL if 'queue_id' is greater than or equal to the
555 * number of supported queues (as reported in the 'n_queues' member of
556 * struct netdev_qos_capabilities by 'get_qos_capabilities'), or if
557 * 'details' is invalid for the type of queue.
559 * This function does not modify 'details', and the caller retains
562 * May be NULL if 'netdev' does not support QoS at all. */
563 int (*set_queue)(struct netdev *netdev,
564 unsigned int queue_id, const struct smap *details);
566 /* Attempts to delete the queue numbered 'queue_id' from 'netdev'.
568 * Should return EINVAL if 'queue_id' is greater than or equal to the
569 * number of supported queues (as reported in the 'n_queues' member of
570 * struct netdev_qos_capabilities by 'get_qos_capabilities'). Should
571 * return EOPNOTSUPP if 'queue_id' is valid but may not be deleted (e.g. if
572 * 'netdev' has a fixed set of queues with the current QoS mode).
574 * May be NULL if 'netdev' does not support QoS at all, or if all of its
575 * QoS modes have fixed sets of queues. */
576 int (*delete_queue)(struct netdev *netdev, unsigned int queue_id);
578 /* Obtains statistics about 'queue_id' on 'netdev'. Fills 'stats' with the
579 * queue's statistics. May set individual members of 'stats' to all-1-bits
580 * if the statistic is unavailable.
582 * May be NULL if 'netdev' does not support QoS at all. */
583 int (*get_queue_stats)(const struct netdev *netdev, unsigned int queue_id,
584 struct netdev_queue_stats *stats);
586 /* Attempts to begin dumping the queues in 'netdev'. On success, returns 0
587 * and initializes '*statep' with any data needed for iteration. On
588 * failure, returns a positive errno value.
590 * May be NULL if 'netdev' does not support QoS at all. */
591 int (*queue_dump_start)(const struct netdev *netdev, void **statep);
593 /* Attempts to retrieve another queue from 'netdev' for 'state', which was
594 * initialized by a successful call to the 'queue_dump_start' function for
595 * 'netdev'. On success, stores a queue ID into '*queue_id' and fills
596 * 'details' with the configuration of the queue with that ID. Returns EOF
597 * if the last queue has been dumped, or a positive errno value on error.
598 * This function will not be called again once it returns nonzero once for
599 * a given iteration (but the 'queue_dump_done' function will be called
602 * The caller initializes and clears 'details' before calling this
603 * function. The caller takes ownership of the string key-values pairs
604 * added to 'details'.
606 * The returned contents of 'details' should be documented as valid for the
607 * given 'type' in the "other_config" column in the "Queue" table in
608 * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
610 * May be NULL if 'netdev' does not support QoS at all. */
611 int (*queue_dump_next)(const struct netdev *netdev, void *state,
612 unsigned int *queue_id, struct smap *details);
614 /* Releases resources from 'netdev' for 'state', which was initialized by a
615 * successful call to the 'queue_dump_start' function for 'netdev'.
617 * May be NULL if 'netdev' does not support QoS at all. */
618 int (*queue_dump_done)(const struct netdev *netdev, void *state);
620 /* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
621 * ID, its statistics, and the 'aux' specified by the caller. The order of
622 * iteration is unspecified, but (when successful) each queue must be
623 * visited exactly once.
625 * 'cb' will not modify or free the statistics passed in. */
626 int (*dump_queue_stats)(const struct netdev *netdev,
627 void (*cb)(unsigned int queue_id,
628 struct netdev_queue_stats *,
632 /* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask. If
633 * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared.
635 * This function may be set to null if it would always return EOPNOTSUPP
637 int (*set_in4)(struct netdev *netdev, struct in_addr addr,
638 struct in_addr mask);
640 /* Returns all assigned IP address to 'netdev' and returns 0.
641 * API allocates array of address and masks and set it to
642 * '*addr' and '*mask'.
643 * Otherwise, returns a positive errno value and sets '*addr', '*mask
644 * and '*n_addr' to NULL.
646 * The following error values have well-defined meanings:
648 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv6 address.
650 * - EOPNOTSUPP: No IPv6 network stack attached to 'netdev'.
652 * 'addr' may be null, in which case the address itself is not reported. */
653 int (*get_addr_list)(const struct netdev *netdev, struct in6_addr **in,
654 struct in6_addr **mask, int *n_in6);
656 /* Adds 'router' as a default IP gateway for the TCP/IP stack that
657 * corresponds to 'netdev'.
659 * This function may be set to null if it would always return EOPNOTSUPP
661 int (*add_router)(struct netdev *netdev, struct in_addr router);
663 /* Looks up the next hop for 'host' in the host's routing table. If
664 * successful, stores the next hop gateway's address (0 if 'host' is on a
665 * directly connected network) in '*next_hop' and a copy of the name of the
666 * device to reach 'host' in '*netdev_name', and returns 0. The caller is
667 * responsible for freeing '*netdev_name' (by calling free()).
669 * This function may be set to null if it would always return EOPNOTSUPP
671 int (*get_next_hop)(const struct in_addr *host, struct in_addr *next_hop,
674 /* Retrieves driver information of the device.
676 * Populates 'smap' with key-value pairs representing the status of the
677 * device. 'smap' is a set of key-value string pairs representing netdev
678 * type specific information. For more information see
679 * ovs-vswitchd.conf.db(5).
681 * The caller is responsible for destroying 'smap' and its data.
683 * This function may be set to null if it would always return EOPNOTSUPP
685 int (*get_status)(const struct netdev *netdev, struct smap *smap);
687 /* Looks up the ARP table entry for 'ip' on 'netdev' and stores the
688 * corresponding MAC address in 'mac'. A return value of ENXIO, in
689 * particular, indicates that there is no ARP table entry for 'ip' on
692 * This function may be set to null if it would always return EOPNOTSUPP
694 int (*arp_lookup)(const struct netdev *netdev, ovs_be32 ip,
695 struct eth_addr *mac);
697 /* Retrieves the current set of flags on 'netdev' into '*old_flags'. Then,
698 * turns off the flags that are set to 1 in 'off' and turns on the flags
699 * that are set to 1 in 'on'. (No bit will be set to 1 in both 'off' and
700 * 'on'; that is, off & on == 0.)
702 * This function may be invoked from a signal handler. Therefore, it
703 * should not do anything that is not signal-safe (such as logging). */
704 int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
705 enum netdev_flags on, enum netdev_flags *old_flags);
707 /* If the provider called netdev_request_reconfigure(), the upper layer
708 * will eventually call this. The provider can update the device
709 * configuration knowing that the upper layer will not call rxq_recv() or
710 * send() until this function returns.
712 * On error, the configuration is indeterminant and the device cannot be
713 * used to send and receive packets until a successful configuration is
715 int (*reconfigure)(struct netdev *netdev);
716 /* ## -------------------- ## */
717 /* ## netdev_rxq Functions ## */
718 /* ## -------------------- ## */
720 /* If a particular netdev class does not support receiving packets, all these
721 * function pointers must be NULL. */
723 /* Life-cycle functions for a netdev_rxq. See the large comment above on
724 * struct netdev_class. */
725 struct netdev_rxq *(*rxq_alloc)(void);
726 int (*rxq_construct)(struct netdev_rxq *);
727 void (*rxq_destruct)(struct netdev_rxq *);
728 void (*rxq_dealloc)(struct netdev_rxq *);
730 /* Attempts to receive a batch of packets from 'rx'. In 'batch', the
731 * caller supplies 'packets' as the pointer to the beginning of an array
732 * of MAX_RX_BATCH pointers to dp_packet. If successful, the
733 * implementation stores pointers to up to MAX_RX_BATCH dp_packets into
734 * the array, transferring ownership of the packets to the caller, stores
735 * the number of received packets into 'count', and returns 0.
737 * The implementation does not necessarily initialize any non-data members
738 * of 'packets' in 'batch'. That is, the caller must initialize layer
739 * pointers and metadata itself, if desired, e.g. with pkt_metadata_init()
740 * and miniflow_extract().
742 * Implementations should allocate buffers with DP_NETDEV_HEADROOM bytes of
745 * Returns EAGAIN immediately if no packet is ready to be received or
746 * another positive errno value if an error was encountered. */
747 int (*rxq_recv)(struct netdev_rxq *rx, struct dp_packet_batch *batch);
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 */