2 * Copyright (c) 2010 Nicira Networks.
3 * Distributed under the terms of the GNU GPL version 2.
5 * Significant portions of this file may be copied from parts of the Linux
6 * kernel, by Linus Torvalds and others.
9 #include <linux/dcache.h>
10 #include <linux/etherdevice.h>
12 #include <linux/kernel.h>
13 #include <linux/list.h>
14 #include <linux/mutex.h>
15 #include <linux/percpu.h>
16 #include <linux/rtnetlink.h>
20 extern struct vport_ops netdev_vport_ops;
21 extern struct vport_ops internal_vport_ops;
22 extern struct vport_ops gre_vport_ops;
24 static struct vport_ops *base_vport_ops_list[] = {
30 static const struct vport_ops **vport_ops_list;
31 static int n_vport_types;
33 static struct hlist_head *dev_table;
34 #define VPORT_HASH_BUCKETS 1024
36 /* Both RTNL lock and vport_mutex need to be held when updating dev_table.
38 * If you use vport_locate and then perform some operations, you need to hold
39 * one of these locks if you don't want the vport to be deleted out from under
42 * If you get a reference to a vport through a dp_port, it is protected
43 * by RCU and you need to hold rcu_read_lock instead when reading.
45 * If multiple locks are taken, the hierarchy is:
50 static DEFINE_MUTEX(vport_mutex);
53 * vport_lock - acquire vport lock
55 * Acquire global vport lock. See above comment about locking requirements
56 * and specific function definitions. May sleep.
61 mutex_lock(&vport_mutex);
65 * vport_unlock - release vport lock
67 * Release lock acquired with vport_lock.
72 mutex_unlock(&vport_mutex);
75 #define ASSERT_VPORT() do { \
76 if (unlikely(!mutex_is_locked(&vport_mutex))) { \
77 printk(KERN_ERR "openvswitch: vport lock not held at %s (%d)\n", \
78 __FILE__, __LINE__); \
84 * vport_init - initialize vport subsystem
86 * Called at module load time to initialize the vport subsystem and any
87 * compiled in vport types.
95 dev_table = kzalloc(VPORT_HASH_BUCKETS * sizeof(struct hlist_head),
102 vport_ops_list = kmalloc(ARRAY_SIZE(base_vport_ops_list) *
103 sizeof(struct vport_ops *), GFP_KERNEL);
104 if (!vport_ops_list) {
106 goto error_dev_table;
109 for (i = 0; i < ARRAY_SIZE(base_vport_ops_list); i++) {
110 struct vport_ops *new_ops = base_vport_ops_list[i];
112 if (new_ops->get_stats && new_ops->flags & VPORT_F_GEN_STATS) {
113 printk(KERN_INFO "openvswitch: both get_stats() and VPORT_F_GEN_STATS defined on vport %s, dropping VPORT_F_GEN_STATS\n", new_ops->type);
114 new_ops->flags &= ~VPORT_F_GEN_STATS;
118 err = new_ops->init();
123 vport_ops_list[n_vport_types++] = new_ops;
124 else if (new_ops->flags & VPORT_F_REQUIRED) {
146 for (i = 0; i < VPORT_HASH_BUCKETS; i++) {
147 struct hlist_head *bucket = &dev_table[i];
149 struct hlist_node *node, *next;
151 hlist_for_each_entry_safe(vport, node, next, bucket, hash_node)
160 * vport_exit - shutdown vport subsystem
162 * Called at module exit time to shutdown the vport subsystem and any
163 * initialized vport types.
172 for (i = 0; i < n_vport_types; i++) {
173 if (vport_ops_list[i]->exit)
174 vport_ops_list[i]->exit();
177 kfree(vport_ops_list);
182 * vport_add - add vport device (for userspace callers)
184 * @uvport_config: New port configuration.
186 * Creates a new vport with the specified configuration (which is dependent
187 * on device type). This function is for userspace callers and assumes no
191 do_vport_add(struct odp_vport_add *vport_config)
196 vport_config->port_type[VPORT_TYPE_SIZE - 1] = '\0';
197 vport_config->devname[IFNAMSIZ - 1] = '\0';
201 vport = vport_locate(vport_config->devname);
208 vport = __vport_add(vport_config->devname, vport_config->port_type,
209 vport_config->config);
213 err = PTR_ERR(vport);
221 vport_add(const struct odp_vport_add __user *uvport_config)
223 struct odp_vport_add vport_config;
225 if (copy_from_user(&vport_config, uvport_config, sizeof(struct odp_vport_add)))
228 return do_vport_add(&vport_config);
232 * vport_mod - modify existing vport device (for userspace callers)
234 * @uvport_config: New configuration for vport
236 * Modifies an existing device with the specified configuration (which is
237 * dependent on device type). This function is for userspace callers and
238 * assumes no locks are held.
241 do_vport_mod(struct odp_vport_mod *vport_config)
246 vport_config->devname[IFNAMSIZ - 1] = '\0';
250 vport = vport_locate(vport_config->devname);
257 err = __vport_mod(vport, vport_config->config);
266 vport_mod(const struct odp_vport_mod __user *uvport_config)
268 struct odp_vport_mod vport_config;
270 if (copy_from_user(&vport_config, uvport_config, sizeof(struct odp_vport_mod)))
273 return do_vport_mod(&vport_config);
277 * vport_del - delete existing vport device (for userspace callers)
279 * @udevname: Name of device to delete
281 * Deletes the specified device. Detaches the device from a datapath first
282 * if it is attached. Deleting the device will fail if it does not exist or it
283 * is the datapath local port. It is also possible to fail for less obvious
284 * reasons, such as lack of memory. This function is for userspace callers and
285 * assumes no locks are held.
288 vport_del(const char __user *udevname)
290 char devname[IFNAMSIZ];
292 struct dp_port *dp_port;
296 retval = strncpy_from_user(devname, udevname, IFNAMSIZ);
299 else if (retval >= IFNAMSIZ)
300 return -ENAMETOOLONG;
304 vport = vport_locate(devname);
310 dp_port = vport_get_dp_port(vport);
312 struct datapath *dp = dp_port->dp;
314 mutex_lock(&dp->mutex);
316 if (!strcmp(dp_name(dp), devname)) {
321 err = dp_detach_port(dp_port, 0);
324 mutex_unlock(&dp->mutex);
331 err = __vport_del(vport);
340 * vport_stats_get - retrieve device stats (for userspace callers)
342 * @ustats_req: Stats request parameters.
344 * Retrieves transmit, receive, and error stats for the given device. This
345 * function is for userspace callers and assumes no locks are held.
348 vport_stats_get(struct odp_vport_stats_req __user *ustats_req)
350 struct odp_vport_stats_req stats_req;
354 if (copy_from_user(&stats_req, ustats_req, sizeof(struct odp_vport_stats_req)))
357 stats_req.devname[IFNAMSIZ - 1] = '\0';
361 vport = vport_locate(stats_req.devname);
367 if (vport->ops->get_stats)
368 err = vport->ops->get_stats(vport, &stats_req.stats);
369 else if (vport->ops->flags & VPORT_F_GEN_STATS) {
372 memset(&stats_req.stats, 0, sizeof(struct odp_vport_stats));
374 for_each_possible_cpu(i) {
375 const struct vport_percpu_stats *percpu_stats;
377 percpu_stats = per_cpu_ptr(vport->percpu_stats, i);
378 stats_req.stats.rx_bytes += percpu_stats->rx_bytes;
379 stats_req.stats.rx_packets += percpu_stats->rx_packets;
380 stats_req.stats.tx_bytes += percpu_stats->tx_bytes;
381 stats_req.stats.tx_packets += percpu_stats->tx_packets;
384 spin_lock_bh(&vport->err_stats.lock);
386 stats_req.stats.rx_dropped = vport->err_stats.rx_dropped;
387 stats_req.stats.rx_errors = vport->err_stats.rx_errors
388 + vport->err_stats.rx_frame_err
389 + vport->err_stats.rx_over_err
390 + vport->err_stats.rx_crc_err;
391 stats_req.stats.rx_frame_err = vport->err_stats.rx_frame_err;
392 stats_req.stats.rx_over_err = vport->err_stats.rx_over_err;
393 stats_req.stats.rx_crc_err = vport->err_stats.rx_crc_err;
394 stats_req.stats.tx_dropped = vport->err_stats.tx_dropped;
395 stats_req.stats.tx_errors = vport->err_stats.tx_errors;
396 stats_req.stats.collisions = vport->err_stats.collisions;
398 spin_unlock_bh(&vport->err_stats.lock);
408 if (copy_to_user(ustats_req, &stats_req, sizeof(struct odp_vport_stats_req)))
415 * vport_ether_get - retrieve device Ethernet address (for userspace callers)
417 * @uvport_ether: Ethernet address request parameters.
419 * Retrieves the Ethernet address of the given device. This function is for
420 * userspace callers and assumes no locks are held.
423 vport_ether_get(struct odp_vport_ether __user *uvport_ether)
425 struct odp_vport_ether vport_ether;
429 if (copy_from_user(&vport_ether, uvport_ether, sizeof(struct odp_vport_ether)))
432 vport_ether.devname[IFNAMSIZ - 1] = '\0';
436 vport = vport_locate(vport_ether.devname);
442 memcpy(vport_ether.ether_addr, vport_get_addr(vport), ETH_ALEN);
448 if (copy_to_user(uvport_ether, &vport_ether, sizeof(struct odp_vport_ether)))
455 * vport_ether_set - set device Ethernet address (for userspace callers)
457 * @uvport_ether: Ethernet address request parameters.
459 * Sets the Ethernet address of the given device. Some devices may not support
460 * setting the Ethernet address, in which case the result will always be
461 * -EOPNOTSUPP. This function is for userspace callers and assumes no locks
465 vport_ether_set(struct odp_vport_ether __user *uvport_ether)
467 struct odp_vport_ether vport_ether;
471 if (copy_from_user(&vport_ether, uvport_ether, sizeof(struct odp_vport_ether)))
474 vport_ether.devname[IFNAMSIZ - 1] = '\0';
479 vport = vport_locate(vport_ether.devname);
485 err = vport_set_addr(vport, vport_ether.ether_addr);
494 * vport_mut_get - retrieve device MTU (for userspace callers)
496 * @uvport_mtu: MTU request parameters.
498 * Retrieves the MTU of the given device. This function is for userspace
499 * callers and assumes no locks are held.
502 vport_mtu_get(struct odp_vport_mtu __user *uvport_mtu)
504 struct odp_vport_mtu vport_mtu;
508 if (copy_from_user(&vport_mtu, uvport_mtu, sizeof(struct odp_vport_mtu)))
511 vport_mtu.devname[IFNAMSIZ - 1] = '\0';
515 vport = vport_locate(vport_mtu.devname);
521 vport_mtu.mtu = vport_get_mtu(vport);
527 if (copy_to_user(uvport_mtu, &vport_mtu, sizeof(struct odp_vport_mtu)))
534 * vport_mtu_set - set device MTU (for userspace callers)
536 * @uvport_mtu: MTU request parameters.
538 * Sets the MTU of the given device. Some devices may not support setting the
539 * MTU, in which case the result will always be -EOPNOTSUPP. This function is
540 * for userspace callers and assumes no locks are held.
543 vport_mtu_set(struct odp_vport_mtu __user *uvport_mtu)
545 struct odp_vport_mtu vport_mtu;
549 if (copy_from_user(&vport_mtu, uvport_mtu, sizeof(struct odp_vport_mtu)))
552 vport_mtu.devname[IFNAMSIZ - 1] = '\0';
557 vport = vport_locate(vport_mtu.devname);
563 err = vport_set_mtu(vport, vport_mtu.mtu);
571 static struct hlist_head *
572 hash_bucket(const char *name)
574 unsigned int hash = full_name_hash(name, strlen(name));
575 return &dev_table[hash & (VPORT_HASH_BUCKETS - 1)];
579 * vport_locate - find a port that has already been created
581 * @name: name of port to find
583 * Either RTNL or vport lock must be acquired before calling this function
584 * and held while using the found port. See the locking comments at the
588 vport_locate(const char *name)
590 struct hlist_head *bucket = hash_bucket(name);
592 struct hlist_node *node;
594 if (unlikely(!mutex_is_locked(&vport_mutex) && !rtnl_is_locked())) {
595 printk(KERN_ERR "openvswitch: neither RTNL nor vport lock held in vport_locate\n");
599 hlist_for_each_entry(vport, node, bucket, hash_node)
600 if (!strcmp(name, vport_get_name(vport)))
607 register_vport(struct vport *vport)
609 hlist_add_head(&vport->hash_node, hash_bucket(vport_get_name(vport)));
613 unregister_vport(struct vport *vport)
615 hlist_del(&vport->hash_node);
619 * vport_alloc - allocate and initialize new vport
621 * @priv_size: Size of private data area to allocate.
622 * @ops: vport device ops
624 * Allocate and initialize a new vport defined by @ops. The vport will contain
625 * a private data area of size @priv_size that can be accessed using
626 * vport_priv(). vports that are no longer needed should be released with
630 vport_alloc(int priv_size, const struct vport_ops *ops)
635 alloc_size = sizeof(struct vport);
637 alloc_size = ALIGN(alloc_size, VPORT_ALIGN);
638 alloc_size += priv_size;
641 vport = kzalloc(alloc_size, GFP_KERNEL);
643 return ERR_PTR(-ENOMEM);
647 if (vport->ops->flags & VPORT_F_GEN_STATS) {
648 vport->percpu_stats = alloc_percpu(struct vport_percpu_stats);
649 if (!vport->percpu_stats)
650 return ERR_PTR(-ENOMEM);
652 spin_lock_init(&vport->err_stats.lock);
659 * vport_free - uninitialize and free vport
661 * @vport: vport to free
663 * Frees a vport allocated with vport_alloc() when it is no longer needed.
666 vport_free(struct vport *vport)
668 if (vport->ops->flags & VPORT_F_GEN_STATS)
669 free_percpu(vport->percpu_stats);
675 * __vport_add - add vport device (for kernel callers)
677 * @name: Name of new device.
678 * @type: Type of new device (to be matched against types in registered vport
680 * @config: Device type specific configuration. Userspace pointer.
682 * Creates a new vport with the specified configuration (which is dependent
683 * on device type). Both RTNL and vport locks must be held.
686 __vport_add(const char *name, const char *type, const void __user *config)
695 for (i = 0; i < n_vport_types; i++) {
696 if (!strcmp(vport_ops_list[i]->type, type)) {
697 vport = vport_ops_list[i]->create(name, config);
699 err = PTR_ERR(vport);
703 register_vport(vport);
715 * __vport_mod - modify existing vport device (for kernel callers)
717 * @vport: vport to modify.
718 * @config: Device type specific configuration. Userspace pointer.
720 * Modifies an existing device with the specified configuration (which is
721 * dependent on device type). Both RTNL and vport locks must be held.
724 __vport_mod(struct vport *vport, const void __user *config)
729 if (vport->ops->modify)
730 return vport->ops->modify(vport, config);
736 * __vport_del - delete existing vport device (for kernel callers)
738 * @vport: vport to delete.
740 * Deletes the specified device. The device must not be currently attached to
741 * a datapath. It is possible to fail for reasons such as lack of memory.
742 * Both RTNL and vport locks must be held.
745 __vport_del(struct vport *vport)
749 BUG_ON(vport_get_dp_port(vport));
751 unregister_vport(vport);
753 return vport->ops->destroy(vport);
757 * vport_attach - attach a vport to a datapath
759 * @vport: vport to attach.
760 * @dp_port: Datapath port to attach the vport to.
762 * Attaches a vport to a specific datapath so that packets may be exchanged.
763 * Both ports must be currently unattached. @dp_port must be successfully
764 * attached to a vport before it is connected to a datapath and must not be
765 * modified while connected. RTNL lock and the appropriate DP mutex must be held.
768 vport_attach(struct vport *vport, struct dp_port *dp_port)
775 if (vport_get_dp_port(vport))
778 if (vport->ops->attach) {
781 err = vport->ops->attach(vport);
786 dp_port->vport = vport;
787 rcu_assign_pointer(vport->dp_port, dp_port);
793 * vport_detach - detach a vport from a datapath
795 * @vport: vport to detach.
797 * Detaches a vport from a datapath. May fail for a variety of reasons,
798 * including lack of memory. RTNL lock and the appropriate DP mutex must be held.
801 vport_detach(struct vport *vport)
803 struct dp_port *dp_port;
807 dp_port = vport_get_dp_port(vport);
811 dp_port->vport = NULL;
812 rcu_assign_pointer(vport->dp_port, NULL);
814 if (vport->ops->detach)
815 return vport->ops->detach(vport);
821 * vport_set_mtu - set device MTU (for kernel callers)
823 * @vport: vport on which to set MTU.
826 * Sets the MTU of the given device. Some devices may not support setting the
827 * MTU, in which case the result will always be -EOPNOTSUPP. RTNL lock must
831 vport_set_mtu(struct vport *vport, int mtu)
838 if (vport->ops->set_mtu)
839 return vport->ops->set_mtu(vport, mtu);
845 * vport_set_addr - set device Ethernet address (for kernel callers)
847 * @vport: vport on which to set Ethernet address.
848 * @addr: New address.
850 * Sets the Ethernet address of the given device. Some devices may not support
851 * setting the Ethernet address, in which case the result will always be
852 * -EOPNOTSUPP. RTNL lock must be held.
855 vport_set_addr(struct vport *vport, const unsigned char *addr)
859 if (!is_valid_ether_addr(addr))
860 return -EADDRNOTAVAIL;
862 if (vport->ops->set_addr)
863 return vport->ops->set_addr(vport, addr);
869 * vport_get_name - retrieve device name
871 * @vport: vport from which to retrieve the name.
873 * Retrieves the name of the given device. Either RTNL lock or rcu_read_lock
874 * must be held for the entire duration that the name is in use.
877 vport_get_name(const struct vport *vport)
879 return vport->ops->get_name(vport);
883 * vport_get_type - retrieve device type
885 * @vport: vport from which to retrieve the type.
887 * Retrieves the type of the given device. Either RTNL lock or rcu_read_lock
888 * must be held for the entire duration that the type is in use.
891 vport_get_type(const struct vport *vport)
893 return vport->ops->type;
897 * vport_get_addr - retrieve device Ethernet address (for kernel callers)
899 * @vport: vport from which to retrieve the Ethernet address.
901 * Retrieves the Ethernet address of the given device. Either RTNL lock or
902 * rcu_read_lock must be held for the entire duration that the Ethernet address
905 const unsigned char *
906 vport_get_addr(const struct vport *vport)
908 return vport->ops->get_addr(vport);
912 * vport_get_dp_port - retrieve attached datapath port
914 * @vport: vport from which to retrieve the datapath port.
916 * Retrieves the attached datapath port or null if not attached. Either RTNL
917 * lock or rcu_read_lock must be held for the entire duration that the datapath
918 * port is being accessed.
921 vport_get_dp_port(const struct vport *vport)
923 return rcu_dereference(vport->dp_port);
927 * vport_get_kobj - retrieve associated kobj
929 * @vport: vport from which to retrieve the associated kobj
931 * Retrieves the associated kobj or null if no kobj. The returned kobj is
932 * valid for as long as the vport exists.
935 vport_get_kobj(const struct vport *vport)
937 if (vport->ops->get_kobj)
938 return vport->ops->get_kobj(vport);
944 * vport_get_flags - retrieve device flags
946 * @vport: vport from which to retrieve the flags
948 * Retrieves the flags of the given device. Either RTNL lock or rcu_read_lock
952 vport_get_flags(const struct vport *vport)
954 return vport->ops->get_dev_flags(vport);
958 * vport_get_flags - check whether device is running
960 * @vport: vport on which to check status.
962 * Checks whether the given device is running. Either RTNL lock or
963 * rcu_read_lock must be held.
966 vport_is_running(const struct vport *vport)
968 return vport->ops->is_running(vport);
972 * vport_get_flags - retrieve device operating state
974 * @vport: vport from which to check status
976 * Retrieves the RFC2863 operstate of the given device. Either RTNL lock or
977 * rcu_read_lock must be held.
980 vport_get_operstate(const struct vport *vport)
982 return vport->ops->get_operstate(vport);
986 * vport_get_ifindex - retrieve device system interface index
988 * @vport: vport from which to retrieve index
990 * Retrieves the system interface index of the given device. Not all devices
991 * will have system indexes, in which case the index of the datapath local
992 * port is returned. Returns a negative index on error. Either RTNL lock or
993 * rcu_read_lock must be held.
996 vport_get_ifindex(const struct vport *vport)
998 const struct dp_port *dp_port;
1000 if (vport->ops->get_ifindex)
1001 return vport->ops->get_ifindex(vport);
1003 /* If we don't actually have an ifindex, use the local port's.
1004 * Userspace doesn't check it anyways. */
1005 dp_port = vport_get_dp_port(vport);
1009 return vport_get_ifindex(dp_port->dp->ports[ODPP_LOCAL]->vport);
1013 * vport_get_iflink - retrieve device system link index
1015 * @vport: vport from which to retrieve index
1017 * Retrieves the system link index of the given device. The link is the index
1018 * of the interface on which the packet will actually be sent. In most cases
1019 * this is the same as the ifindex but may be different for tunnel devices.
1020 * Returns a negative index on error. Either RTNL lock or rcu_read_lock must
1024 vport_get_iflink(const struct vport *vport)
1026 if (vport->ops->get_iflink)
1027 return vport->ops->get_iflink(vport);
1029 /* If we don't have an iflink, use the ifindex. In most cases they
1031 return vport_get_ifindex(vport);
1035 * vport_get_mtu - retrieve device MTU (for kernel callers)
1037 * @vport: vport from which to retrieve MTU
1039 * Retrieves the MTU of the given device. Either RTNL lock or rcu_read_lock
1043 vport_get_mtu(const struct vport *vport)
1045 return vport->ops->get_mtu(vport);
1049 * vport_receive - pass up received packet to the datapath for processing
1051 * @vport: vport that received the packet
1052 * @skb: skb that was received
1054 * Must be called with rcu_read_lock and bottom halves disabled. The packet
1055 * cannot be shared and skb->data should point to the Ethernet header. The
1056 * caller must have already called compute_ip_summed() to initialize the
1057 * checksumming fields.
1060 vport_receive(struct vport *vport, struct sk_buff *skb)
1062 struct dp_port *dp_port = vport_get_dp_port(vport);
1065 vport_record_error(vport, VPORT_E_RX_DROPPED);
1071 if (vport->ops->flags & VPORT_F_GEN_STATS) {
1072 struct vport_percpu_stats *stats;
1076 stats = per_cpu_ptr(vport->percpu_stats, smp_processor_id());
1077 stats->rx_packets++;
1078 stats->rx_bytes += skb->len;
1083 if (!(vport->ops->flags & VPORT_F_TUN_ID))
1084 OVS_CB(skb)->tun_id = 0;
1086 dp_process_received_packet(dp_port, skb);
1090 * vport_send - send a packet on a device
1092 * @vport: vport on which to send the packet
1095 * Sends the given packet and returns the length of data sent. Either RTNL
1096 * lock or rcu_read_lock must be held.
1099 vport_send(struct vport *vport, struct sk_buff *skb)
1103 sent = vport->ops->send(vport, skb);
1105 if (vport->ops->flags & VPORT_F_GEN_STATS && sent > 0) {
1106 struct vport_percpu_stats *stats;
1110 stats = per_cpu_ptr(vport->percpu_stats, smp_processor_id());
1111 stats->tx_packets++;
1112 stats->tx_bytes += sent;
1121 * vport_record_error - indicate device error to generic stats layer
1123 * @vport: vport that encountered the error
1124 * @err_type: one of enum vport_err_type types to indicate the error type
1126 * If using the vport generic stats layer indicate that an error of the given
1130 vport_record_error(struct vport *vport, enum vport_err_type err_type)
1132 if (vport->ops->flags & VPORT_F_GEN_STATS) {
1134 spin_lock_bh(&vport->err_stats.lock);
1137 case VPORT_E_RX_DROPPED:
1138 vport->err_stats.rx_dropped++;
1141 case VPORT_E_RX_ERROR:
1142 vport->err_stats.rx_errors++;
1145 case VPORT_E_RX_FRAME:
1146 vport->err_stats.rx_frame_err++;
1149 case VPORT_E_RX_OVER:
1150 vport->err_stats.rx_over_err++;
1153 case VPORT_E_RX_CRC:
1154 vport->err_stats.rx_crc_err++;
1157 case VPORT_E_TX_DROPPED:
1158 vport->err_stats.tx_dropped++;
1161 case VPORT_E_TX_ERROR:
1162 vport->err_stats.tx_errors++;
1165 case VPORT_E_COLLISION:
1166 vport->err_stats.collisions++;
1170 spin_unlock_bh(&vport->err_stats.lock);
1175 * vport_gen_ether_addr - generate an Ethernet address
1177 * @addr: location to store generated address
1179 * Generates a random Ethernet address for use when creating a device that
1180 * has no natural address.
1183 vport_gen_ether_addr(u8 *addr)
1185 random_ether_addr(addr);
1187 /* Set the OUI to the Nicira one. */
1192 /* Set the top bit to indicate random address. */