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 fatal_signal_block();
301 error = restore_flags(netdev);
302 list_remove(&netdev->node);
303 fatal_signal_unblock();
305 VLOG_WARN("failed to restore network device flags on %s: %s",
306 name, strerror(error));
310 netdev->class->close(netdev);
315 /* Returns true if a network device named 'name' exists and may be opened,
316 * otherwise false. */
318 netdev_exists(const char *name)
320 struct netdev *netdev;
323 error = netdev_open(name, NETDEV_ETH_TYPE_NONE, &netdev);
325 netdev_close(netdev);
328 if (error != ENODEV) {
329 VLOG_WARN("failed to open network device %s: %s",
330 name, strerror(error));
336 /* Initializes 'svec' with a list of the names of all known network devices. */
338 netdev_enumerate(struct svec *svec)
348 for (i = 0; i < n_netdev_classes; i++) {
349 const struct netdev_class *class = netdev_classes[i];
350 if (class->enumerate) {
351 int retval = class->enumerate(svec);
353 VLOG_WARN("failed to enumerate %s network devices: %s",
354 class->type, strerror(retval));
364 /* Attempts to receive a packet from 'netdev' into 'buffer', which the caller
365 * must have initialized with sufficient room for the packet. The space
366 * required to receive any packet is ETH_HEADER_LEN bytes, plus VLAN_HEADER_LEN
367 * bytes, plus the device's MTU (which may be retrieved via netdev_get_mtu()).
368 * (Some devices do not allow for a VLAN header, in which case VLAN_HEADER_LEN
369 * need not be included.)
371 * If a packet is successfully retrieved, returns 0. In this case 'buffer' is
372 * guaranteed to contain at least ETH_TOTAL_MIN bytes. Otherwise, returns a
373 * positive errno value. Returns EAGAIN immediately if no packet is ready to
377 netdev_recv(struct netdev *netdev, struct ofpbuf *buffer)
381 assert(buffer->size == 0);
382 assert(ofpbuf_tailroom(buffer) >= ETH_TOTAL_MIN);
384 retval = netdev->class->recv(netdev,
385 buffer->data, ofpbuf_tailroom(buffer));
387 COVERAGE_INC(netdev_received);
388 buffer->size += retval;
389 if (buffer->size < ETH_TOTAL_MIN) {
390 ofpbuf_put_zeros(buffer, ETH_TOTAL_MIN - buffer->size);
398 /* Registers with the poll loop to wake up from the next call to poll_block()
399 * when a packet is ready to be received with netdev_recv() on 'netdev'. */
401 netdev_recv_wait(struct netdev *netdev)
403 netdev->class->recv_wait(netdev);
406 /* Discards all packets waiting to be received from 'netdev'. */
408 netdev_drain(struct netdev *netdev)
410 return netdev->class->drain(netdev);
413 /* Sends 'buffer' on 'netdev'. Returns 0 if successful, otherwise a positive
414 * errno value. Returns EAGAIN without blocking if the packet cannot be queued
415 * immediately. Returns EMSGSIZE if a partial packet was transmitted or if
416 * the packet is too big or too small to transmit on the device.
418 * The caller retains ownership of 'buffer' in all cases.
420 * The kernel maintains a packet transmission queue, so the caller is not
421 * expected to do additional queuing of packets. */
423 netdev_send(struct netdev *netdev, const struct ofpbuf *buffer)
425 int error = netdev->class->send(netdev, buffer->data, buffer->size);
427 COVERAGE_INC(netdev_sent);
432 /* Registers with the poll loop to wake up from the next call to poll_block()
433 * when the packet transmission queue has sufficient room to transmit a packet
434 * with netdev_send().
436 * The kernel maintains a packet transmission queue, so the client is not
437 * expected to do additional queuing of packets. Thus, this function is
438 * unlikely to ever be used. It is included for completeness. */
440 netdev_send_wait(struct netdev *netdev)
442 return netdev->class->send_wait(netdev);
445 /* Attempts to set 'netdev''s MAC address to 'mac'. Returns 0 if successful,
446 * otherwise a positive errno value. */
448 netdev_set_etheraddr(struct netdev *netdev, const uint8_t mac[ETH_ADDR_LEN])
450 return netdev->class->set_etheraddr(netdev, mac);
453 /* Retrieves 'netdev''s MAC address. If successful, returns 0 and copies the
454 * the MAC address into 'mac'. On failure, returns a positive errno value and
455 * clears 'mac' to all-zeros. */
457 netdev_get_etheraddr(const struct netdev *netdev, uint8_t mac[ETH_ADDR_LEN])
459 return netdev->class->get_etheraddr(netdev, mac);
462 /* Returns the name of the network device that 'netdev' represents,
463 * e.g. "eth0". The caller must not modify or free the returned string. */
465 netdev_get_name(const struct netdev *netdev)
470 /* Retrieves the MTU of 'netdev'. The MTU is the maximum size of transmitted
471 * (and received) packets, in bytes, not including the hardware header; thus,
472 * this is typically 1500 bytes for Ethernet devices.
474 * If successful, returns 0 and stores the MTU size in '*mtup'. On failure,
475 * returns a positive errno value and stores ETH_PAYLOAD_MAX (1500) in
478 netdev_get_mtu(const struct netdev *netdev, int *mtup)
480 int error = netdev->class->get_mtu(netdev, mtup);
482 VLOG_WARN_RL(&rl, "failed to retrieve MTU for network device %s: %s",
483 netdev_get_name(netdev), strerror(error));
484 *mtup = ETH_PAYLOAD_MAX;
489 /* Returns the ifindex of 'netdev', if successful, as a positive number. On
490 * failure, returns a negative errno value.
492 * The desired semantics of the ifindex value are a combination of those
493 * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An ifindex
494 * value should be unique within a host and remain stable at least until
495 * reboot. SNMP says an ifindex "ranges between 1 and the value of ifNumber"
496 * but many systems do not follow this rule anyhow.
499 netdev_get_ifindex(const struct netdev *netdev)
501 return netdev->class->get_ifindex(netdev);
504 /* Stores the features supported by 'netdev' into each of '*current',
505 * '*advertised', '*supported', and '*peer' that are non-null. Each value is a
506 * bitmap of "enum ofp_port_features" bits, in host byte order. Returns 0 if
507 * successful, otherwise a positive errno value. On failure, all of the
508 * passed-in values are set to 0. */
510 netdev_get_features(struct netdev *netdev,
511 uint32_t *current, uint32_t *advertised,
512 uint32_t *supported, uint32_t *peer)
521 advertised = &dummy[1];
524 supported = &dummy[2];
530 error = netdev->class->get_features(netdev, current, advertised, supported,
533 *current = *advertised = *supported = *peer = 0;
538 /* Set the features advertised by 'netdev' to 'advertise'. Returns 0 if
539 * successful, otherwise a positive errno value. */
541 netdev_set_advertisements(struct netdev *netdev, uint32_t advertise)
543 return (netdev->class->set_advertisements
544 ? netdev->class->set_advertisements(netdev, advertise)
548 /* If 'netdev' has an assigned IPv4 address, sets '*address' to that address
549 * and '*netmask' to its netmask and returns 0. Otherwise, returns a positive
550 * errno value and sets '*address' to 0 (INADDR_ANY).
552 * The following error values have well-defined meanings:
554 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv4 address.
556 * - EOPNOTSUPP: No IPv4 network stack attached to 'netdev'.
558 * 'address' or 'netmask' or both may be null, in which case the address or netmask
559 * is not reported. */
561 netdev_get_in4(const struct netdev *netdev,
562 struct in_addr *address_, struct in_addr *netmask_)
564 struct in_addr address;
565 struct in_addr netmask;
568 error = (netdev->class->get_in4
569 ? netdev->class->get_in4(netdev, &address, &netmask)
572 address_->s_addr = error ? 0 : address.s_addr;
575 netmask_->s_addr = error ? 0 : netmask.s_addr;
580 /* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask. If
581 * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared. Returns a
582 * positive errno value. */
584 netdev_set_in4(struct netdev *netdev, struct in_addr addr, struct in_addr mask)
586 return (netdev->class->set_in4
587 ? netdev->class->set_in4(netdev, addr, mask)
591 /* Adds 'router' as a default IP gateway for the TCP/IP stack that corresponds
594 netdev_add_router(struct netdev *netdev, struct in_addr router)
596 COVERAGE_INC(netdev_add_router);
597 return (netdev->class->add_router
598 ? netdev->class->add_router(netdev, router)
602 /* Looks up the next hop for 'host' for the TCP/IP stack that corresponds to
603 * 'netdev'. If a route cannot not be determined, sets '*next_hop' to 0,
604 * '*netdev_name' to null, and returns a positive errno value. Otherwise, if a
605 * next hop is found, stores the next hop gateway's address (0 if 'host' is on
606 * a directly connected network) in '*next_hop' and a copy of the name of the
607 * device to reach 'host' in '*netdev_name', and returns 0. The caller is
608 * responsible for freeing '*netdev_name' (by calling free()). */
610 netdev_get_next_hop(const struct netdev *netdev,
611 const struct in_addr *host, struct in_addr *next_hop,
614 int error = (netdev->class->get_next_hop
615 ? netdev->class->get_next_hop(host, next_hop, netdev_name)
618 next_hop->s_addr = 0;
624 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address and
625 * returns 0. Otherwise, returns a positive errno value and sets '*in6' to
626 * all-zero-bits (in6addr_any).
628 * The following error values have well-defined meanings:
630 * - EADDRNOTAVAIL: 'netdev' has no assigned IPv6 address.
632 * - EOPNOTSUPP: No IPv6 network stack attached to 'netdev'.
634 * 'in6' may be null, in which case the address itself is not reported. */
636 netdev_get_in6(const struct netdev *netdev, struct in6_addr *in6)
638 struct in6_addr dummy;
641 error = (netdev->class->get_in6
642 ? netdev->class->get_in6(netdev, in6 ? in6 : &dummy)
645 memset(in6, 0, sizeof *in6);
650 /* On 'netdev', turns off the flags in 'off' and then turns on the flags in
651 * 'on'. If 'permanent' is true, the changes will persist; otherwise, they
652 * will be reverted when 'netdev' is closed or the program exits. Returns 0 if
653 * successful, otherwise a positive errno value. */
655 do_update_flags(struct netdev *netdev, enum netdev_flags off,
656 enum netdev_flags on, enum netdev_flags *old_flagsp,
659 enum netdev_flags old_flags;
662 error = netdev->class->update_flags(netdev, off & ~on, on, &old_flags);
664 VLOG_WARN_RL(&rl, "failed to %s flags for network device %s: %s",
665 off || on ? "set" : "get", netdev_get_name(netdev),
668 } else if ((off || on) && !permanent) {
669 enum netdev_flags new_flags = (old_flags & ~off) | on;
670 enum netdev_flags changed_flags = old_flags ^ new_flags;
672 if (!netdev->changed_flags) {
673 netdev->save_flags = old_flags;
675 netdev->changed_flags |= changed_flags;
679 *old_flagsp = old_flags;
684 /* Obtains the current flags for 'netdev' and stores them into '*flagsp'.
685 * Returns 0 if successful, otherwise a positive errno value. On failure,
686 * stores 0 into '*flagsp'. */
688 netdev_get_flags(const struct netdev *netdev_, enum netdev_flags *flagsp)
690 struct netdev *netdev = (struct netdev *) netdev_;
691 return do_update_flags(netdev, 0, 0, flagsp, false);
694 /* Sets the flags for 'netdev' to 'flags'.
695 * If 'permanent' is true, the changes will persist; otherwise, they
696 * will be reverted when 'netdev' is closed or the program exits.
697 * Returns 0 if successful, otherwise a positive errno value. */
699 netdev_set_flags(struct netdev *netdev, enum netdev_flags flags,
702 return do_update_flags(netdev, -1, flags, NULL, permanent);
705 /* Turns on the specified 'flags' on 'netdev'.
706 * If 'permanent' is true, the changes will persist; otherwise, they
707 * will be reverted when 'netdev' is closed or the program exits.
708 * Returns 0 if successful, otherwise a positive errno value. */
710 netdev_turn_flags_on(struct netdev *netdev, enum netdev_flags flags,
713 return do_update_flags(netdev, 0, flags, NULL, permanent);
716 /* Turns off the specified 'flags' on 'netdev'.
717 * If 'permanent' is true, the changes will persist; otherwise, they
718 * will be reverted when 'netdev' is closed or the program exits.
719 * Returns 0 if successful, otherwise a positive errno value. */
721 netdev_turn_flags_off(struct netdev *netdev, enum netdev_flags flags,
724 return do_update_flags(netdev, flags, 0, NULL, permanent);
727 /* Looks up the ARP table entry for 'ip' on 'netdev'. If one exists and can be
728 * successfully retrieved, it stores the corresponding MAC address in 'mac' and
729 * returns 0. Otherwise, it returns a positive errno value; in particular,
730 * ENXIO indicates that there is no ARP table entry for 'ip' on 'netdev'. */
732 netdev_arp_lookup(const struct netdev *netdev,
733 uint32_t ip, uint8_t mac[ETH_ADDR_LEN])
735 int error = (netdev->class->arp_lookup
736 ? netdev->class->arp_lookup(netdev, ip, mac)
739 memset(mac, 0, ETH_ADDR_LEN);
744 /* Sets 'carrier' to true if carrier is active (link light is on) on
747 netdev_get_carrier(const struct netdev *netdev, bool *carrier)
749 int error = (netdev->class->get_carrier
750 ? netdev->class->get_carrier(netdev, carrier)
758 /* Retrieves current device stats for 'netdev'. */
760 netdev_get_stats(const struct netdev *netdev, struct netdev_stats *stats)
764 COVERAGE_INC(netdev_get_stats);
765 error = (netdev->class->get_stats
766 ? netdev->class->get_stats(netdev, stats)
769 memset(stats, 0xff, sizeof *stats);
774 /* Attempts to set input rate limiting (policing) policy, such that up to
775 * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative burst
776 * size of 'kbits' kb. */
778 netdev_set_policing(struct netdev *netdev, uint32_t kbits_rate,
779 uint32_t kbits_burst)
781 return (netdev->class->set_policing
782 ? netdev->class->set_policing(netdev, kbits_rate, kbits_burst)
786 /* If 'netdev' is a VLAN network device (e.g. one created with vconfig(8)),
787 * sets '*vlan_vid' to the VLAN VID associated with that device and returns 0.
788 * Otherwise returns a errno value (specifically ENOENT if 'netdev_name' is the
789 * name of a network device that is not a VLAN device) and sets '*vlan_vid' to
792 netdev_get_vlan_vid(const struct netdev *netdev, int *vlan_vid)
794 int error = (netdev->class->get_vlan_vid
795 ? netdev->class->get_vlan_vid(netdev, vlan_vid)
803 /* Returns a network device that has 'in4' as its IP address, if one exists,
804 * otherwise a null pointer. */
806 netdev_find_dev_by_in4(const struct in_addr *in4)
808 struct netdev *netdev;
809 struct svec dev_list;
812 netdev_enumerate(&dev_list);
813 for (i = 0; i < dev_list.n; i++) {
814 const char *name = dev_list.names[i];
815 struct in_addr dev_in4;
817 if (!netdev_open(name, NETDEV_ETH_TYPE_NONE, &netdev)
818 && !netdev_get_in4(netdev, &dev_in4, NULL)
819 && dev_in4.s_addr == in4->s_addr) {
822 netdev_close(netdev);
827 svec_destroy(&dev_list);
831 /* Initializes 'netdev_obj' as a netdev object named 'name' of the
834 * This function adds 'netdev_obj' to a netdev-owned shash, so it is
835 * very important that 'netdev_obj' only be freed after calling
836 * netdev_destroy(). */
838 netdev_obj_init(struct netdev_obj *netdev_obj, const char *name,
839 const struct netdev_class *class, bool created)
841 assert(!shash_find(&netdev_obj_shash, name));
843 netdev_obj->class = class;
844 netdev_obj->ref_cnt = 0;
845 netdev_obj->created = created;
846 netdev_obj->name = xstrdup(name);
847 shash_add(&netdev_obj_shash, name, netdev_obj);
850 /* Returns the class type of 'netdev_obj'.
852 * The caller must not free the returned value. */
853 const char *netdev_obj_get_type(const struct netdev_obj *netdev_obj)
855 return netdev_obj->class->type;
858 /* Returns the name of 'netdev_obj'.
860 * The caller must not free the returned value. */
861 const char *netdev_obj_get_name(const struct netdev_obj *netdev_obj)
863 return netdev_obj->name;
866 /* Initializes 'netdev' as a netdev named 'name' of the specified 'class'.
868 * This function adds 'netdev' to a netdev-owned linked list, so it is very
869 * important that 'netdev' only be freed after calling netdev_close(). */
871 netdev_init(struct netdev *netdev, const char *name,
872 const struct netdev_class *class)
874 netdev->class = class;
875 netdev->name = xstrdup(name);
876 netdev->save_flags = 0;
877 netdev->changed_flags = 0;
878 list_push_back(&netdev_list, &netdev->node);
881 /* Returns the class type of 'netdev'.
883 * The caller must not free the returned value. */
884 const char *netdev_get_type(const struct netdev *netdev)
886 return netdev->class->type;
889 /* Initializes 'notifier' as a netdev notifier for 'netdev', for which
890 * notification will consist of calling 'cb', with auxiliary data 'aux'. */
892 netdev_notifier_init(struct netdev_notifier *notifier, struct netdev *netdev,
893 void (*cb)(struct netdev_notifier *), void *aux)
895 notifier->netdev = netdev;
900 /* Tracks changes in the status of a set of network devices. */
901 struct netdev_monitor {
902 struct shash polled_netdevs;
903 struct shash changed_netdevs;
906 /* Creates and returns a new structure for monitor changes in the status of
907 * network devices. */
908 struct netdev_monitor *
909 netdev_monitor_create(void)
911 struct netdev_monitor *monitor = xmalloc(sizeof *monitor);
912 shash_init(&monitor->polled_netdevs);
913 shash_init(&monitor->changed_netdevs);
917 /* Destroys 'monitor'. */
919 netdev_monitor_destroy(struct netdev_monitor *monitor)
922 struct shash_node *node;
924 SHASH_FOR_EACH (node, &monitor->polled_netdevs) {
925 struct netdev_notifier *notifier = node->data;
926 notifier->netdev->class->poll_remove(notifier);
929 shash_destroy(&monitor->polled_netdevs);
930 shash_destroy(&monitor->changed_netdevs);
936 netdev_monitor_cb(struct netdev_notifier *notifier)
938 struct netdev_monitor *monitor = notifier->aux;
939 const char *name = netdev_get_name(notifier->netdev);
940 if (!shash_find(&monitor->changed_netdevs, name)) {
941 shash_add(&monitor->changed_netdevs, name, NULL);
945 /* Attempts to add 'netdev' as a netdev monitored by 'monitor'. Returns 0 if
946 * successful, otherwise a positive errno value.
948 * Adding a given 'netdev' to a monitor multiple times is equivalent to adding
951 netdev_monitor_add(struct netdev_monitor *monitor, struct netdev *netdev)
953 const char *netdev_name = netdev_get_name(netdev);
955 if (!shash_find(&monitor->polled_netdevs, netdev_name)
956 && netdev->class->poll_add)
958 struct netdev_notifier *notifier;
959 error = netdev->class->poll_add(netdev, netdev_monitor_cb, monitor,
962 assert(notifier->netdev == netdev);
963 shash_add(&monitor->polled_netdevs, netdev_name, notifier);
969 /* Removes 'netdev' from the set of netdevs monitored by 'monitor'. (This has
970 * no effect if 'netdev' is not in the set of devices monitored by
973 netdev_monitor_remove(struct netdev_monitor *monitor, struct netdev *netdev)
975 const char *netdev_name = netdev_get_name(netdev);
976 struct shash_node *node;
978 node = shash_find(&monitor->polled_netdevs, netdev_name);
980 /* Cancel future notifications. */
981 struct netdev_notifier *notifier = node->data;
982 netdev->class->poll_remove(notifier);
983 shash_delete(&monitor->polled_netdevs, node);
985 /* Drop any pending notification. */
986 node = shash_find(&monitor->changed_netdevs, netdev_name);
988 shash_delete(&monitor->changed_netdevs, node);
993 /* Checks for changes to netdevs in the set monitored by 'monitor'. If any of
994 * the attributes (Ethernet address, carrier status, speed or peer-advertised
995 * speed, flags, etc.) of a network device monitored by 'monitor' has changed,
996 * sets '*devnamep' to the name of a device that has changed and returns 0.
997 * The caller is responsible for freeing '*devnamep' (with free()).
999 * If no devices have changed, sets '*devnamep' to NULL and returns EAGAIN.
1002 netdev_monitor_poll(struct netdev_monitor *monitor, char **devnamep)
1004 struct shash_node *node = shash_first(&monitor->changed_netdevs);
1009 *devnamep = xstrdup(node->name);
1010 shash_delete(&monitor->changed_netdevs, node);
1015 /* Registers with the poll loop to wake up from the next call to poll_block()
1016 * when netdev_monitor_poll(monitor) would indicate that a device has
1019 netdev_monitor_poll_wait(const struct netdev_monitor *monitor)
1021 if (!shash_is_empty(&monitor->changed_netdevs)) {
1022 poll_immediate_wake();
1024 /* XXX Nothing needed here for netdev_linux, but maybe other netdev
1025 * classes need help. */
1029 /* Restore the network device flags on 'netdev' to those that were active
1030 * before we changed them. Returns 0 if successful, otherwise a positive
1033 * To avoid reentry, the caller must ensure that fatal signals are blocked. */
1035 restore_flags(struct netdev *netdev)
1037 if (netdev->changed_flags) {
1038 enum netdev_flags restore = netdev->save_flags & netdev->changed_flags;
1039 enum netdev_flags old_flags;
1040 return netdev->class->update_flags(netdev,
1041 netdev->changed_flags & ~restore,
1042 restore, &old_flags);
1047 /* Retores all the flags on all network devices that we modified. Called from
1048 * a signal handler, so it does not attempt to report error conditions. */
1050 restore_all_flags(void *aux UNUSED)
1052 struct netdev *netdev;
1053 LIST_FOR_EACH (netdev, struct netdev, node, &netdev_list) {
1054 restore_flags(netdev);