2 * Copyright (c) 2008, 2009 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
23 #include <netinet/in.h>
29 #include "dynamic-string.h"
30 #include "fatal-signal.h"
32 #include "netdev-provider.h"
35 #include "poll-loop.h"
39 #define THIS_MODULE VLM_netdev
42 static const struct netdev_class *netdev_classes[] = {
47 static int n_netdev_classes = ARRAY_SIZE(netdev_classes);
49 /* All created network devices. */
50 static struct shash netdev_obj_shash = SHASH_INITIALIZER(&netdev_obj_shash);
52 /* All open network devices. */
53 static struct list netdev_list = LIST_INITIALIZER(&netdev_list);
55 /* This is set pretty low because we probably won't learn anything from the
56 * additional log messages. */
57 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
59 static void restore_all_flags(void *aux);
60 static int restore_flags(struct netdev *netdev);
62 /* Attempts to initialize the netdev module. Returns 0 if successful,
63 * otherwise a positive errno value.
65 * Calling this function is optional. If not called explicitly, it will
66 * automatically be called upon the first attempt to open or create a
69 netdev_initialize(void)
71 static int status = -1;
75 fatal_signal_add_hook(restore_all_flags, NULL, true);
78 for (i = j = 0; i < n_netdev_classes; i++) {
79 const struct netdev_class *class = netdev_classes[i];
81 int retval = class->init();
83 netdev_classes[j++] = class;
85 VLOG_ERR("failed to initialize %s network device "
86 "class: %s", class->type, strerror(retval));
92 netdev_classes[j++] = class;
100 /* Performs periodic work needed by all the various kinds of netdevs.
102 * If your program opens any netdevs, it must call this function within its
108 for (i = 0; i < n_netdev_classes; i++) {
109 const struct netdev_class *class = netdev_classes[i];
116 /* Arranges for poll_block() to wake up when netdev_run() needs to be called.
118 * If your program opens any netdevs, it must call this function within its
124 for (i = 0; i < n_netdev_classes; i++) {
125 const struct netdev_class *class = netdev_classes[i];
132 /* Attempts to create a network device object of 'type' with 'name'. 'type'
133 * corresponds to the 'type' field used in the netdev_class * structure.
134 * Arguments for creation are provided in 'args', which may be empty or NULL
135 * if none are needed. */
137 netdev_create(const char *name, const char *type, const struct shash *args)
139 struct shash empty_args = SHASH_INITIALIZER(&empty_args);
148 if (shash_find(&netdev_obj_shash, name)) {
149 VLOG_WARN("attempted to create a netdev object with bound name: %s",
154 for (i = 0; i < n_netdev_classes; i++) {
155 const struct netdev_class *class = netdev_classes[i];
156 if (!strcmp(type, class->type)) {
157 return class->create(name, type, args, true);
161 VLOG_WARN("could not create netdev object of unknown type: %s", type);
166 /* Destroys netdev object 'name'. Netdev objects maintain a reference count
167 * which is incremented on netdev_open() and decremented on netdev_close().
168 * If 'name' has a non-zero reference count, it will not destroy the object
169 * and return EBUSY. */
171 netdev_destroy(const char *name)
173 struct shash_node *node;
174 struct netdev_obj *netdev_obj;
176 node = shash_find(&netdev_obj_shash, name);
181 netdev_obj = node->data;
182 if (netdev_obj->ref_cnt != 0) {
183 VLOG_WARN("attempt to destroy netdev object with %d open handles: %s",
184 netdev_obj->ref_cnt, name);
185 #if 0 /* Temp hack */
190 shash_delete(&netdev_obj_shash, node);
191 netdev_obj->class->destroy(netdev_obj);
196 /* Reconfigures the device object 'name' with 'args'. 'args' may be empty
197 * or NULL if none are needed. */
199 netdev_reconfigure(const char *name, const struct shash *args)
201 struct shash empty_args = SHASH_INITIALIZER(&empty_args);
202 struct netdev_obj *netdev_obj;
208 netdev_obj = shash_find_data(&netdev_obj_shash, name);
213 if (netdev_obj->class->reconfigure) {
214 return netdev_obj->class->reconfigure(netdev_obj, args);
220 /* Opens the network device named 'name' (e.g. "eth0") and returns zero if
221 * successful, otherwise a positive errno value. On success, sets '*netdevp'
222 * to the new network device, otherwise to null.
224 * 'ethertype' may be a 16-bit Ethernet protocol value in host byte order to
225 * capture frames of that type received on the device. It may also be one of
226 * the 'enum netdev_pseudo_ethertype' values to receive frames in one of those
229 netdev_open(const char *name, int ethertype, struct netdev **netdevp)
231 struct netdev_obj *netdev_obj;
232 struct netdev *netdev = NULL;
238 netdev_obj = shash_find_data(&netdev_obj_shash, name);
240 error = netdev_obj->class->open(name, ethertype, &netdev);
242 /* Default to "system". */
243 error = EAFNOSUPPORT;
244 for (i = 0; i < n_netdev_classes; i++) {
245 const struct netdev_class *class = netdev_classes[i];
246 if (!strcmp(class->type, "system")) {
247 struct shash empty_args = SHASH_INITIALIZER(&empty_args);
249 /* Dynamically create the netdev object, but indicate
250 * that it should be destroyed when the the last user
251 * closes its handle. */
252 error = class->create(name, "system", &empty_args, false);
254 error = class->open(name, ethertype, &netdev);
255 netdev_obj = shash_find_data(&netdev_obj_shash, name);
262 netdev_obj->ref_cnt++;
265 *netdevp = error ? NULL : netdev;
269 /* Closes and destroys 'netdev'. */
271 netdev_close(struct netdev *netdev)
274 struct netdev_obj *netdev_obj;
275 char *name = netdev->name;
278 netdev_obj = shash_find_data(&netdev_obj_shash, name);
284 if (netdev_obj->ref_cnt > 0) {
285 netdev_obj->ref_cnt--;
287 VLOG_WARN("netdev %s closed too many times", name);
290 /* If the reference count for the netdev object is zero, and it
291 * was dynamically created by netdev_open(), destroy it. */
292 if (!netdev_obj->ref_cnt && !netdev_obj->created) {
293 netdev_destroy(name);
299 /* Restore flags that we changed, if any. */
300 error = restore_flags(netdev);
301 list_remove(&netdev->node);
303 VLOG_WARN("failed to restore network device flags on %s: %s",
304 name, strerror(error));
308 netdev->class->close(netdev);
313 /* Returns true if a network device named 'name' exists and may be opened,
314 * otherwise false. */
316 netdev_exists(const char *name)
318 struct netdev *netdev;
321 error = netdev_open(name, NETDEV_ETH_TYPE_NONE, &netdev);
323 netdev_close(netdev);
326 if (error != ENODEV) {
327 VLOG_WARN("failed to open network device %s: %s",
328 name, strerror(error));
334 /* Initializes 'svec' with a list of the names of all known network devices. */
336 netdev_enumerate(struct svec *svec)
346 for (i = 0; i < n_netdev_classes; i++) {
347 const struct netdev_class *class = netdev_classes[i];
348 if (class->enumerate) {
349 int retval = class->enumerate(svec);
351 VLOG_WARN("failed to enumerate %s network devices: %s",
352 class->type, strerror(retval));
362 /* Attempts to receive a packet from 'netdev' into 'buffer', which the caller
363 * must have initialized with sufficient room for the packet. The space
364 * required to receive any packet is ETH_HEADER_LEN bytes, plus VLAN_HEADER_LEN
365 * bytes, plus the device's MTU (which may be retrieved via netdev_get_mtu()).
366 * (Some devices do not allow for a VLAN header, in which case VLAN_HEADER_LEN
367 * need not be included.)
369 * If a packet is successfully retrieved, returns 0. In this case 'buffer' is
370 * guaranteed to contain at least ETH_TOTAL_MIN bytes. Otherwise, returns a
371 * positive errno value. Returns EAGAIN immediately if no packet is ready to
375 netdev_recv(struct netdev *netdev, struct ofpbuf *buffer)
379 assert(buffer->size == 0);
380 assert(ofpbuf_tailroom(buffer) >= ETH_TOTAL_MIN);
382 retval = netdev->class->recv(netdev,
383 buffer->data, ofpbuf_tailroom(buffer));
385 COVERAGE_INC(netdev_received);
386 buffer->size += retval;
387 if (buffer->size < ETH_TOTAL_MIN) {
388 ofpbuf_put_zeros(buffer, ETH_TOTAL_MIN - buffer->size);
396 /* Registers with the poll loop to wake up from the next call to poll_block()
397 * when a packet is ready to be received with netdev_recv() on 'netdev'. */
399 netdev_recv_wait(struct netdev *netdev)
401 netdev->class->recv_wait(netdev);
404 /* Discards all packets waiting to be received from 'netdev'. */
406 netdev_drain(struct netdev *netdev)
408 return netdev->class->drain(netdev);
411 /* Sends 'buffer' on 'netdev'. Returns 0 if successful, otherwise a positive
412 * errno value. Returns EAGAIN without blocking if the packet cannot be queued
413 * immediately. Returns EMSGSIZE if a partial packet was transmitted or if
414 * the packet is too big or too small to transmit on the device.
416 * The caller retains ownership of 'buffer' in all cases.
418 * The kernel maintains a packet transmission queue, so the caller is not
419 * expected to do additional queuing of packets. */
421 netdev_send(struct netdev *netdev, const struct ofpbuf *buffer)
423 int error = netdev->class->send(netdev, buffer->data, buffer->size);
425 COVERAGE_INC(netdev_sent);
430 /* Registers with the poll loop to wake up from the next call to poll_block()
431 * when the packet transmission queue has sufficient room to transmit a packet
432 * with netdev_send().
434 * The kernel maintains a packet transmission queue, so the client is not
435 * expected to do additional queuing of packets. Thus, this function is
436 * unlikely to ever be used. It is included for completeness. */
438 netdev_send_wait(struct netdev *netdev)
440 return netdev->class->send_wait(netdev);
443 /* Attempts to set 'netdev''s MAC address to 'mac'. Returns 0 if successful,
444 * otherwise a positive errno value. */
446 netdev_set_etheraddr(struct netdev *netdev, const uint8_t mac[ETH_ADDR_LEN])
448 return netdev->class->set_etheraddr(netdev, mac);
451 /* Retrieves 'netdev''s MAC address. If successful, returns 0 and copies the
452 * the MAC address into 'mac'. On failure, returns a positive errno value and
453 * clears 'mac' to all-zeros. */
455 netdev_get_etheraddr(const struct netdev *netdev, uint8_t mac[ETH_ADDR_LEN])
457 return netdev->class->get_etheraddr(netdev, mac);
460 /* Returns the name of the network device that 'netdev' represents,
461 * e.g. "eth0". The caller must not modify or free the returned string. */
463 netdev_get_name(const struct netdev *netdev)
468 /* Retrieves the MTU of 'netdev'. The MTU is the maximum size of transmitted
469 * (and received) packets, in bytes, not including the hardware header; thus,
470 * this is typically 1500 bytes for Ethernet devices.
472 * If successful, returns 0 and stores the MTU size in '*mtup'. On failure,
473 * returns a positive errno value and stores ETH_PAYLOAD_MAX (1500) in
476 netdev_get_mtu(const struct netdev *netdev, int *mtup)
478 int error = netdev->class->get_mtu(netdev, mtup);
480 VLOG_WARN_RL(&rl, "failed to retrieve MTU for network device %s: %s",
481 netdev_get_name(netdev), strerror(error));
482 *mtup = ETH_PAYLOAD_MAX;
487 /* Returns the ifindex of 'netdev', if successful, as a positive number. On
488 * failure, returns a negative errno value.
490 * The desired semantics of the ifindex value are a combination of those
491 * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An ifindex
492 * value should be unique within a host and remain stable at least until
493 * reboot. SNMP says an ifindex "ranges between 1 and the value of ifNumber"
494 * but many systems do not follow this rule anyhow.
497 netdev_get_ifindex(const struct netdev *netdev)
499 return netdev->class->get_ifindex(netdev);
502 /* Stores the features supported by 'netdev' into each of '*current',
503 * '*advertised', '*supported', and '*peer' that are non-null. Each value is a
504 * bitmap of "enum ofp_port_features" bits, in host byte order. Returns 0 if
505 * successful, otherwise a positive errno value. On failure, all of the
506 * passed-in values are set to 0. */
508 netdev_get_features(struct netdev *netdev,
509 uint32_t *current, uint32_t *advertised,
510 uint32_t *supported, uint32_t *peer)
519 advertised = &dummy[1];
522 supported = &dummy[2];
528 error = netdev->class->get_features(netdev, current, advertised, supported,
531 *current = *advertised = *supported = *peer = 0;
536 /* Set the features advertised by 'netdev' to 'advertise'. Returns 0 if
537 * successful, otherwise a positive errno value. */
539 netdev_set_advertisements(struct netdev *netdev, uint32_t advertise)
541 return (netdev->class->set_advertisements
542 ? netdev->class->set_advertisements(netdev, advertise)
546 /* If 'netdev' has an assigned IPv4 address, sets '*address' to that address
547 * and '*netmask' to its netmask and returns 0. Otherwise, returns a positive
548 * errno value and sets '*address' to 0 (INADDR_ANY).
550 * The following error values have well-defined meanings:
552 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv4 address.
554 * - EOPNOTSUPP: No IPv4 network stack attached to 'netdev'.
556 * 'address' or 'netmask' or both may be null, in which case the address or netmask
557 * is not reported. */
559 netdev_get_in4(const struct netdev *netdev,
560 struct in_addr *address_, struct in_addr *netmask_)
562 struct in_addr address;
563 struct in_addr netmask;
566 error = (netdev->class->get_in4
567 ? netdev->class->get_in4(netdev, &address, &netmask)
570 address_->s_addr = error ? 0 : address.s_addr;
573 netmask_->s_addr = error ? 0 : netmask.s_addr;
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. Returns a
580 * positive errno value. */
582 netdev_set_in4(struct netdev *netdev, struct in_addr addr, struct in_addr mask)
584 return (netdev->class->set_in4
585 ? netdev->class->set_in4(netdev, addr, mask)
589 /* Adds 'router' as a default IP gateway for the TCP/IP stack that corresponds
592 netdev_add_router(struct netdev *netdev, struct in_addr router)
594 COVERAGE_INC(netdev_add_router);
595 return (netdev->class->add_router
596 ? netdev->class->add_router(netdev, router)
600 /* Looks up the next hop for 'host' for the TCP/IP stack that corresponds to
601 * 'netdev'. If a route cannot not be determined, sets '*next_hop' to 0,
602 * '*netdev_name' to null, and returns a positive errno value. Otherwise, if a
603 * next hop is found, stores the next hop gateway's address (0 if 'host' is on
604 * a directly connected network) in '*next_hop' and a copy of the name of the
605 * device to reach 'host' in '*netdev_name', and returns 0. The caller is
606 * responsible for freeing '*netdev_name' (by calling free()). */
608 netdev_get_next_hop(const struct netdev *netdev,
609 const struct in_addr *host, struct in_addr *next_hop,
612 int error = (netdev->class->get_next_hop
613 ? netdev->class->get_next_hop(host, next_hop, netdev_name)
616 next_hop->s_addr = 0;
622 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address and
623 * returns 0. Otherwise, returns a positive errno value and sets '*in6' to
624 * all-zero-bits (in6addr_any).
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 * 'in6' may be null, in which case the address itself is not reported. */
634 netdev_get_in6(const struct netdev *netdev, struct in6_addr *in6)
636 struct in6_addr dummy;
639 error = (netdev->class->get_in6
640 ? netdev->class->get_in6(netdev, in6 ? in6 : &dummy)
643 memset(in6, 0, sizeof *in6);
648 /* On 'netdev', turns off the flags in 'off' and then turns on the flags in
649 * 'on'. If 'permanent' is true, the changes will persist; otherwise, they
650 * will be reverted when 'netdev' is closed or the program exits. Returns 0 if
651 * successful, otherwise a positive errno value. */
653 do_update_flags(struct netdev *netdev, enum netdev_flags off,
654 enum netdev_flags on, enum netdev_flags *old_flagsp,
657 enum netdev_flags old_flags;
660 error = netdev->class->update_flags(netdev, off & ~on, on, &old_flags);
662 VLOG_WARN_RL(&rl, "failed to %s flags for network device %s: %s",
663 off || on ? "set" : "get", netdev_get_name(netdev),
666 } else if ((off || on) && !permanent) {
667 enum netdev_flags new_flags = (old_flags & ~off) | on;
668 enum netdev_flags changed_flags = old_flags ^ new_flags;
670 if (!netdev->changed_flags) {
671 netdev->save_flags = old_flags;
673 netdev->changed_flags |= changed_flags;
677 *old_flagsp = old_flags;
682 /* Obtains the current flags for 'netdev' and stores them into '*flagsp'.
683 * Returns 0 if successful, otherwise a positive errno value. On failure,
684 * stores 0 into '*flagsp'. */
686 netdev_get_flags(const struct netdev *netdev_, enum netdev_flags *flagsp)
688 struct netdev *netdev = (struct netdev *) netdev_;
689 return do_update_flags(netdev, 0, 0, flagsp, false);
692 /* Sets the flags for 'netdev' to 'flags'.
693 * If 'permanent' is true, the changes will persist; otherwise, they
694 * will be reverted when 'netdev' is closed or the program exits.
695 * Returns 0 if successful, otherwise a positive errno value. */
697 netdev_set_flags(struct netdev *netdev, enum netdev_flags flags,
700 return do_update_flags(netdev, -1, flags, NULL, permanent);
703 /* Turns on the specified 'flags' on 'netdev'.
704 * If 'permanent' is true, the changes will persist; otherwise, they
705 * will be reverted when 'netdev' is closed or the program exits.
706 * Returns 0 if successful, otherwise a positive errno value. */
708 netdev_turn_flags_on(struct netdev *netdev, enum netdev_flags flags,
711 return do_update_flags(netdev, 0, flags, NULL, permanent);
714 /* Turns off the specified 'flags' on 'netdev'.
715 * If 'permanent' is true, the changes will persist; otherwise, they
716 * will be reverted when 'netdev' is closed or the program exits.
717 * Returns 0 if successful, otherwise a positive errno value. */
719 netdev_turn_flags_off(struct netdev *netdev, enum netdev_flags flags,
722 return do_update_flags(netdev, flags, 0, NULL, permanent);
725 /* Looks up the ARP table entry for 'ip' on 'netdev'. If one exists and can be
726 * successfully retrieved, it stores the corresponding MAC address in 'mac' and
727 * returns 0. Otherwise, it returns a positive errno value; in particular,
728 * ENXIO indicates that there is no ARP table entry for 'ip' on 'netdev'. */
730 netdev_arp_lookup(const struct netdev *netdev,
731 uint32_t ip, uint8_t mac[ETH_ADDR_LEN])
733 int error = (netdev->class->arp_lookup
734 ? netdev->class->arp_lookup(netdev, ip, mac)
737 memset(mac, 0, ETH_ADDR_LEN);
742 /* Sets 'carrier' to true if carrier is active (link light is on) on
745 netdev_get_carrier(const struct netdev *netdev, bool *carrier)
747 int error = (netdev->class->get_carrier
748 ? netdev->class->get_carrier(netdev, carrier)
756 /* Retrieves current device stats for 'netdev'. */
758 netdev_get_stats(const struct netdev *netdev, struct netdev_stats *stats)
762 COVERAGE_INC(netdev_get_stats);
763 error = (netdev->class->get_stats
764 ? netdev->class->get_stats(netdev, stats)
767 memset(stats, 0xff, sizeof *stats);
772 /* Attempts to set input rate limiting (policing) policy, such that up to
773 * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative burst
774 * size of 'kbits' kb. */
776 netdev_set_policing(struct netdev *netdev, uint32_t kbits_rate,
777 uint32_t kbits_burst)
779 return (netdev->class->set_policing
780 ? netdev->class->set_policing(netdev, kbits_rate, kbits_burst)
784 /* If 'netdev' is a VLAN network device (e.g. one created with vconfig(8)),
785 * sets '*vlan_vid' to the VLAN VID associated with that device and returns 0.
786 * Otherwise returns a errno value (specifically ENOENT if 'netdev_name' is the
787 * name of a network device that is not a VLAN device) and sets '*vlan_vid' to
790 netdev_get_vlan_vid(const struct netdev *netdev, int *vlan_vid)
792 int error = (netdev->class->get_vlan_vid
793 ? netdev->class->get_vlan_vid(netdev, vlan_vid)
801 /* Returns a network device that has 'in4' as its IP address, if one exists,
802 * otherwise a null pointer. */
804 netdev_find_dev_by_in4(const struct in_addr *in4)
806 struct netdev *netdev;
807 struct svec dev_list;
810 netdev_enumerate(&dev_list);
811 for (i = 0; i < dev_list.n; i++) {
812 const char *name = dev_list.names[i];
813 struct in_addr dev_in4;
815 if (!netdev_open(name, NETDEV_ETH_TYPE_NONE, &netdev)
816 && !netdev_get_in4(netdev, &dev_in4, NULL)
817 && dev_in4.s_addr == in4->s_addr) {
820 netdev_close(netdev);
825 svec_destroy(&dev_list);
829 /* Initializes 'netdev_obj' as a netdev object named 'name' of the
832 * This function adds 'netdev_obj' to a netdev-owned shash, so it is
833 * very important that 'netdev_obj' only be freed after calling
834 * netdev_destroy(). */
836 netdev_obj_init(struct netdev_obj *netdev_obj, const char *name,
837 const struct netdev_class *class, bool created)
839 assert(!shash_find(&netdev_obj_shash, name));
841 netdev_obj->class = class;
842 netdev_obj->ref_cnt = 0;
843 netdev_obj->created = created;
844 netdev_obj->name = xstrdup(name);
845 shash_add(&netdev_obj_shash, name, netdev_obj);
848 /* Returns the class type of 'netdev_obj'.
850 * The caller must not free the returned value. */
851 const char *netdev_obj_get_type(const struct netdev_obj *netdev_obj)
853 return netdev_obj->class->type;
856 /* Returns the name of 'netdev_obj'.
858 * The caller must not free the returned value. */
859 const char *netdev_obj_get_name(const struct netdev_obj *netdev_obj)
861 return netdev_obj->name;
864 /* Initializes 'netdev' as a netdev named 'name' of the specified 'class'.
866 * This function adds 'netdev' to a netdev-owned linked list, so it is very
867 * important that 'netdev' only be freed after calling netdev_close(). */
869 netdev_init(struct netdev *netdev, const char *name,
870 const struct netdev_class *class)
872 netdev->class = class;
873 netdev->name = xstrdup(name);
874 netdev->save_flags = 0;
875 netdev->changed_flags = 0;
876 list_push_back(&netdev_list, &netdev->node);
879 /* Returns the class type of 'netdev'.
881 * The caller must not free the returned value. */
882 const char *netdev_get_type(const struct netdev *netdev)
884 return netdev->class->type;
887 /* Initializes 'notifier' as a netdev notifier for 'netdev', for which
888 * notification will consist of calling 'cb', with auxiliary data 'aux'. */
890 netdev_notifier_init(struct netdev_notifier *notifier, struct netdev *netdev,
891 void (*cb)(struct netdev_notifier *), void *aux)
893 notifier->netdev = netdev;
898 /* Tracks changes in the status of a set of network devices. */
899 struct netdev_monitor {
900 struct shash polled_netdevs;
901 struct shash changed_netdevs;
904 /* Creates and returns a new structure for monitor changes in the status of
905 * network devices. */
906 struct netdev_monitor *
907 netdev_monitor_create(void)
909 struct netdev_monitor *monitor = xmalloc(sizeof *monitor);
910 shash_init(&monitor->polled_netdevs);
911 shash_init(&monitor->changed_netdevs);
915 /* Destroys 'monitor'. */
917 netdev_monitor_destroy(struct netdev_monitor *monitor)
920 struct shash_node *node;
922 SHASH_FOR_EACH (node, &monitor->polled_netdevs) {
923 struct netdev_notifier *notifier = node->data;
924 notifier->netdev->class->poll_remove(notifier);
927 shash_destroy(&monitor->polled_netdevs);
928 shash_destroy(&monitor->changed_netdevs);
934 netdev_monitor_cb(struct netdev_notifier *notifier)
936 struct netdev_monitor *monitor = notifier->aux;
937 const char *name = netdev_get_name(notifier->netdev);
938 if (!shash_find(&monitor->changed_netdevs, name)) {
939 shash_add(&monitor->changed_netdevs, name, NULL);
943 /* Attempts to add 'netdev' as a netdev monitored by 'monitor'. Returns 0 if
944 * successful, otherwise a positive errno value.
946 * Adding a given 'netdev' to a monitor multiple times is equivalent to adding
949 netdev_monitor_add(struct netdev_monitor *monitor, struct netdev *netdev)
951 const char *netdev_name = netdev_get_name(netdev);
953 if (!shash_find(&monitor->polled_netdevs, netdev_name)
954 && netdev->class->poll_add)
956 struct netdev_notifier *notifier;
957 error = netdev->class->poll_add(netdev, netdev_monitor_cb, monitor,
960 assert(notifier->netdev == netdev);
961 shash_add(&monitor->polled_netdevs, netdev_name, notifier);
967 /* Removes 'netdev' from the set of netdevs monitored by 'monitor'. (This has
968 * no effect if 'netdev' is not in the set of devices monitored by
971 netdev_monitor_remove(struct netdev_monitor *monitor, struct netdev *netdev)
973 const char *netdev_name = netdev_get_name(netdev);
974 struct shash_node *node;
976 node = shash_find(&monitor->polled_netdevs, netdev_name);
978 /* Cancel future notifications. */
979 struct netdev_notifier *notifier = node->data;
980 netdev->class->poll_remove(notifier);
981 shash_delete(&monitor->polled_netdevs, node);
983 /* Drop any pending notification. */
984 node = shash_find(&monitor->changed_netdevs, netdev_name);
986 shash_delete(&monitor->changed_netdevs, node);
991 /* Checks for changes to netdevs in the set monitored by 'monitor'. If any of
992 * the attributes (Ethernet address, carrier status, speed or peer-advertised
993 * speed, flags, etc.) of a network device monitored by 'monitor' has changed,
994 * sets '*devnamep' to the name of a device that has changed and returns 0.
995 * The caller is responsible for freeing '*devnamep' (with free()).
997 * If no devices have changed, sets '*devnamep' to NULL and returns EAGAIN.
1000 netdev_monitor_poll(struct netdev_monitor *monitor, char **devnamep)
1002 struct shash_node *node = shash_first(&monitor->changed_netdevs);
1007 *devnamep = xstrdup(node->name);
1008 shash_delete(&monitor->changed_netdevs, node);
1013 /* Registers with the poll loop to wake up from the next call to poll_block()
1014 * when netdev_monitor_poll(monitor) would indicate that a device has
1017 netdev_monitor_poll_wait(const struct netdev_monitor *monitor)
1019 if (!shash_is_empty(&monitor->changed_netdevs)) {
1020 poll_immediate_wake();
1022 /* XXX Nothing needed here for netdev_linux, but maybe other netdev
1023 * classes need help. */
1027 /* Restore the network device flags on 'netdev' to those that were active
1028 * before we changed them. Returns 0 if successful, otherwise a positive
1031 * To avoid reentry, the caller must ensure that fatal signals are blocked. */
1033 restore_flags(struct netdev *netdev)
1035 if (netdev->changed_flags) {
1036 enum netdev_flags restore = netdev->save_flags & netdev->changed_flags;
1037 enum netdev_flags old_flags;
1038 return netdev->class->update_flags(netdev,
1039 netdev->changed_flags & ~restore,
1040 restore, &old_flags);
1045 /* Retores all the flags on all network devices that we modified. Called from
1046 * a signal handler, so it does not attempt to report error conditions. */
1048 restore_all_flags(void *aux UNUSED)
1050 struct netdev *netdev;
1051 LIST_FOR_EACH (netdev, struct netdev, node, &netdev_list) {
1052 restore_flags(netdev);