rcu: split list.h and move rcu-protected lists into rculist.h
[safe/jmp/linux-2.6] / net / 8021q / vlan.c
1 /*
2  * INET         802.1Q VLAN
3  *              Ethernet-type device handling.
4  *
5  * Authors:     Ben Greear <greearb@candelatech.com>
6  *              Please send support related email to: netdev@vger.kernel.org
7  *              VLAN Home Page: http://www.candelatech.com/~greear/vlan.html
8  *
9  * Fixes:
10  *              Fix for packet capture - Nick Eggleston <nick@dccinc.com>;
11  *              Add HW acceleration hooks - David S. Miller <davem@redhat.com>;
12  *              Correct all the locking - David S. Miller <davem@redhat.com>;
13  *              Use hash table for VLAN groups - David S. Miller <davem@redhat.com>
14  *
15  *              This program is free software; you can redistribute it and/or
16  *              modify it under the terms of the GNU General Public License
17  *              as published by the Free Software Foundation; either version
18  *              2 of the License, or (at your option) any later version.
19  */
20
21 #include <asm/uaccess.h> /* for copy_from_user */
22 #include <linux/capability.h>
23 #include <linux/module.h>
24 #include <linux/netdevice.h>
25 #include <linux/skbuff.h>
26 #include <net/datalink.h>
27 #include <linux/mm.h>
28 #include <linux/in.h>
29 #include <linux/init.h>
30 #include <linux/rculist.h>
31 #include <net/p8022.h>
32 #include <net/arp.h>
33 #include <linux/rtnetlink.h>
34 #include <linux/notifier.h>
35 #include <net/net_namespace.h>
36 #include <net/netns/generic.h>
37
38 #include <linux/if_vlan.h>
39 #include "vlan.h"
40 #include "vlanproc.h"
41
42 #define DRV_VERSION "1.8"
43
44 /* Global VLAN variables */
45
46 int vlan_net_id;
47
48 /* Our listing of VLAN group(s) */
49 static struct hlist_head vlan_group_hash[VLAN_GRP_HASH_SIZE];
50
51 static char vlan_fullname[] = "802.1Q VLAN Support";
52 static char vlan_version[] = DRV_VERSION;
53 static char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
54 static char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";
55
56 static struct packet_type vlan_packet_type = {
57         .type = __constant_htons(ETH_P_8021Q),
58         .func = vlan_skb_recv, /* VLAN receive method */
59 };
60
61 /* End of global variables definitions. */
62
63 static inline unsigned int vlan_grp_hashfn(unsigned int idx)
64 {
65         return ((idx >> VLAN_GRP_HASH_SHIFT) ^ idx) & VLAN_GRP_HASH_MASK;
66 }
67
68 /* Must be invoked with RCU read lock (no preempt) */
69 static struct vlan_group *__vlan_find_group(struct net_device *real_dev)
70 {
71         struct vlan_group *grp;
72         struct hlist_node *n;
73         int hash = vlan_grp_hashfn(real_dev->ifindex);
74
75         hlist_for_each_entry_rcu(grp, n, &vlan_group_hash[hash], hlist) {
76                 if (grp->real_dev == real_dev)
77                         return grp;
78         }
79
80         return NULL;
81 }
82
83 /*  Find the protocol handler.  Assumes VID < VLAN_VID_MASK.
84  *
85  * Must be invoked with RCU read lock (no preempt)
86  */
87 struct net_device *__find_vlan_dev(struct net_device *real_dev,
88                                    unsigned short VID)
89 {
90         struct vlan_group *grp = __vlan_find_group(real_dev);
91
92         if (grp)
93                 return vlan_group_get_device(grp, VID);
94
95         return NULL;
96 }
97
98 static void vlan_group_free(struct vlan_group *grp)
99 {
100         int i;
101
102         for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
103                 kfree(grp->vlan_devices_arrays[i]);
104         kfree(grp);
105 }
106
107 static struct vlan_group *vlan_group_alloc(struct net_device *real_dev)
108 {
109         struct vlan_group *grp;
110
111         grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL);
112         if (!grp)
113                 return NULL;
114
115         grp->real_dev = real_dev;
116         hlist_add_head_rcu(&grp->hlist,
117                         &vlan_group_hash[vlan_grp_hashfn(real_dev->ifindex)]);
118         return grp;
119 }
120
121 static int vlan_group_prealloc_vid(struct vlan_group *vg, int vid)
122 {
123         struct net_device **array;
124         unsigned int size;
125
126         ASSERT_RTNL();
127
128         array = vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN];
129         if (array != NULL)
130                 return 0;
131
132         size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
133         array = kzalloc(size, GFP_KERNEL);
134         if (array == NULL)
135                 return -ENOBUFS;
136
137         vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN] = array;
138         return 0;
139 }
140
141 static void vlan_rcu_free(struct rcu_head *rcu)
142 {
143         vlan_group_free(container_of(rcu, struct vlan_group, rcu));
144 }
145
146 void unregister_vlan_dev(struct net_device *dev)
147 {
148         struct vlan_dev_info *vlan = vlan_dev_info(dev);
149         struct net_device *real_dev = vlan->real_dev;
150         struct vlan_group *grp;
151         unsigned short vlan_id = vlan->vlan_id;
152
153         ASSERT_RTNL();
154
155         grp = __vlan_find_group(real_dev);
156         BUG_ON(!grp);
157
158         /* Take it out of our own structures, but be sure to interlock with
159          * HW accelerating devices or SW vlan input packet processing.
160          */
161         if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
162                 real_dev->vlan_rx_kill_vid(real_dev, vlan_id);
163
164         vlan_group_set_device(grp, vlan_id, NULL);
165         grp->nr_vlans--;
166
167         synchronize_net();
168
169         /* If the group is now empty, kill off the group. */
170         if (grp->nr_vlans == 0) {
171                 if (real_dev->features & NETIF_F_HW_VLAN_RX)
172                         real_dev->vlan_rx_register(real_dev, NULL);
173
174                 hlist_del_rcu(&grp->hlist);
175
176                 /* Free the group, after all cpu's are done. */
177                 call_rcu(&grp->rcu, vlan_rcu_free);
178         }
179
180         /* Get rid of the vlan's reference to real_dev */
181         dev_put(real_dev);
182
183         unregister_netdevice(dev);
184 }
185
186 static void vlan_transfer_operstate(const struct net_device *dev,
187                                     struct net_device *vlandev)
188 {
189         /* Have to respect userspace enforced dormant state
190          * of real device, also must allow supplicant running
191          * on VLAN device
192          */
193         if (dev->operstate == IF_OPER_DORMANT)
194                 netif_dormant_on(vlandev);
195         else
196                 netif_dormant_off(vlandev);
197
198         if (netif_carrier_ok(dev)) {
199                 if (!netif_carrier_ok(vlandev))
200                         netif_carrier_on(vlandev);
201         } else {
202                 if (netif_carrier_ok(vlandev))
203                         netif_carrier_off(vlandev);
204         }
205 }
206
207 int vlan_check_real_dev(struct net_device *real_dev, unsigned short vlan_id)
208 {
209         char *name = real_dev->name;
210
211         if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
212                 pr_info("8021q: VLANs not supported on %s\n", name);
213                 return -EOPNOTSUPP;
214         }
215
216         if ((real_dev->features & NETIF_F_HW_VLAN_RX) &&
217             !real_dev->vlan_rx_register) {
218                 pr_info("8021q: device %s has buggy VLAN hw accel\n", name);
219                 return -EOPNOTSUPP;
220         }
221
222         if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
223             (!real_dev->vlan_rx_add_vid || !real_dev->vlan_rx_kill_vid)) {
224                 pr_info("8021q: Device %s has buggy VLAN hw accel\n", name);
225                 return -EOPNOTSUPP;
226         }
227
228         /* The real device must be up and operating in order to
229          * assosciate a VLAN device with it.
230          */
231         if (!(real_dev->flags & IFF_UP))
232                 return -ENETDOWN;
233
234         if (__find_vlan_dev(real_dev, vlan_id) != NULL)
235                 return -EEXIST;
236
237         return 0;
238 }
239
240 int register_vlan_dev(struct net_device *dev)
241 {
242         struct vlan_dev_info *vlan = vlan_dev_info(dev);
243         struct net_device *real_dev = vlan->real_dev;
244         unsigned short vlan_id = vlan->vlan_id;
245         struct vlan_group *grp, *ngrp = NULL;
246         int err;
247
248         grp = __vlan_find_group(real_dev);
249         if (!grp) {
250                 ngrp = grp = vlan_group_alloc(real_dev);
251                 if (!grp)
252                         return -ENOBUFS;
253         }
254
255         err = vlan_group_prealloc_vid(grp, vlan_id);
256         if (err < 0)
257                 goto out_free_group;
258
259         err = register_netdevice(dev);
260         if (err < 0)
261                 goto out_free_group;
262
263         /* Account for reference in struct vlan_dev_info */
264         dev_hold(real_dev);
265
266         vlan_transfer_operstate(real_dev, dev);
267         linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
268
269         /* So, got the sucker initialized, now lets place
270          * it into our local structure.
271          */
272         vlan_group_set_device(grp, vlan_id, dev);
273         grp->nr_vlans++;
274
275         if (ngrp && real_dev->features & NETIF_F_HW_VLAN_RX)
276                 real_dev->vlan_rx_register(real_dev, ngrp);
277         if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
278                 real_dev->vlan_rx_add_vid(real_dev, vlan_id);
279
280         return 0;
281
282 out_free_group:
283         if (ngrp)
284                 vlan_group_free(ngrp);
285         return err;
286 }
287
288 /*  Attach a VLAN device to a mac address (ie Ethernet Card).
289  *  Returns 0 if the device was created or a negative error code otherwise.
290  */
291 static int register_vlan_device(struct net_device *real_dev,
292                                 unsigned short VLAN_ID)
293 {
294         struct net_device *new_dev;
295         struct net *net = dev_net(real_dev);
296         struct vlan_net *vn = net_generic(net, vlan_net_id);
297         char name[IFNAMSIZ];
298         int err;
299
300         if (VLAN_ID >= VLAN_VID_MASK)
301                 return -ERANGE;
302
303         err = vlan_check_real_dev(real_dev, VLAN_ID);
304         if (err < 0)
305                 return err;
306
307         /* Gotta set up the fields for the device. */
308         switch (vn->name_type) {
309         case VLAN_NAME_TYPE_RAW_PLUS_VID:
310                 /* name will look like:  eth1.0005 */
311                 snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, VLAN_ID);
312                 break;
313         case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
314                 /* Put our vlan.VID in the name.
315                  * Name will look like:  vlan5
316                  */
317                 snprintf(name, IFNAMSIZ, "vlan%i", VLAN_ID);
318                 break;
319         case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
320                 /* Put our vlan.VID in the name.
321                  * Name will look like:  eth0.5
322                  */
323                 snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, VLAN_ID);
324                 break;
325         case VLAN_NAME_TYPE_PLUS_VID:
326                 /* Put our vlan.VID in the name.
327                  * Name will look like:  vlan0005
328                  */
329         default:
330                 snprintf(name, IFNAMSIZ, "vlan%.4i", VLAN_ID);
331         }
332
333         new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name,
334                                vlan_setup);
335
336         if (new_dev == NULL)
337                 return -ENOBUFS;
338
339         dev_net_set(new_dev, net);
340         /* need 4 bytes for extra VLAN header info,
341          * hope the underlying device can handle it.
342          */
343         new_dev->mtu = real_dev->mtu;
344
345         vlan_dev_info(new_dev)->vlan_id = VLAN_ID; /* 1 through VLAN_VID_MASK */
346         vlan_dev_info(new_dev)->real_dev = real_dev;
347         vlan_dev_info(new_dev)->dent = NULL;
348         vlan_dev_info(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
349
350         new_dev->rtnl_link_ops = &vlan_link_ops;
351         err = register_vlan_dev(new_dev);
352         if (err < 0)
353                 goto out_free_newdev;
354
355         return 0;
356
357 out_free_newdev:
358         free_netdev(new_dev);
359         return err;
360 }
361
362 static void vlan_sync_address(struct net_device *dev,
363                               struct net_device *vlandev)
364 {
365         struct vlan_dev_info *vlan = vlan_dev_info(vlandev);
366
367         /* May be called without an actual change */
368         if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr))
369                 return;
370
371         /* vlan address was different from the old address and is equal to
372          * the new address */
373         if (compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
374             !compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
375                 dev_unicast_delete(dev, vlandev->dev_addr, ETH_ALEN);
376
377         /* vlan address was equal to the old address and is different from
378          * the new address */
379         if (!compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
380             compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
381                 dev_unicast_add(dev, vlandev->dev_addr, ETH_ALEN);
382
383         memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
384 }
385
386 static void __vlan_device_event(struct net_device *dev, unsigned long event)
387 {
388         switch (event) {
389         case NETDEV_CHANGENAME:
390                 vlan_proc_rem_dev(dev);
391                 if (vlan_proc_add_dev(dev) < 0)
392                         pr_warning("8021q: failed to change proc name for %s\n",
393                                         dev->name);
394                 break;
395         case NETDEV_REGISTER:
396                 if (vlan_proc_add_dev(dev) < 0)
397                         pr_warning("8021q: failed to add proc entry for %s\n",
398                                         dev->name);
399                 break;
400         case NETDEV_UNREGISTER:
401                 vlan_proc_rem_dev(dev);
402                 break;
403         }
404 }
405
406 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
407                              void *ptr)
408 {
409         struct net_device *dev = ptr;
410         struct vlan_group *grp;
411         int i, flgs;
412         struct net_device *vlandev;
413
414         if (is_vlan_dev(dev)) {
415                 __vlan_device_event(dev, event);
416                 goto out;
417         }
418
419         grp = __vlan_find_group(dev);
420         if (!grp)
421                 goto out;
422
423         /* It is OK that we do not hold the group lock right now,
424          * as we run under the RTNL lock.
425          */
426
427         switch (event) {
428         case NETDEV_CHANGE:
429                 /* Propagate real device state to vlan devices */
430                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
431                         vlandev = vlan_group_get_device(grp, i);
432                         if (!vlandev)
433                                 continue;
434
435                         vlan_transfer_operstate(dev, vlandev);
436                 }
437                 break;
438
439         case NETDEV_CHANGEADDR:
440                 /* Adjust unicast filters on underlying device */
441                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
442                         vlandev = vlan_group_get_device(grp, i);
443                         if (!vlandev)
444                                 continue;
445
446                         flgs = vlandev->flags;
447                         if (!(flgs & IFF_UP))
448                                 continue;
449
450                         vlan_sync_address(dev, vlandev);
451                 }
452                 break;
453
454         case NETDEV_DOWN:
455                 /* Put all VLANs for this dev in the down state too.  */
456                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
457                         vlandev = vlan_group_get_device(grp, i);
458                         if (!vlandev)
459                                 continue;
460
461                         flgs = vlandev->flags;
462                         if (!(flgs & IFF_UP))
463                                 continue;
464
465                         dev_change_flags(vlandev, flgs & ~IFF_UP);
466                 }
467                 break;
468
469         case NETDEV_UP:
470                 /* Put all VLANs for this dev in the up state too.  */
471                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
472                         vlandev = vlan_group_get_device(grp, i);
473                         if (!vlandev)
474                                 continue;
475
476                         flgs = vlandev->flags;
477                         if (flgs & IFF_UP)
478                                 continue;
479
480                         dev_change_flags(vlandev, flgs | IFF_UP);
481                 }
482                 break;
483
484         case NETDEV_UNREGISTER:
485                 /* Delete all VLANs for this dev. */
486                 for (i = 0; i < VLAN_GROUP_ARRAY_LEN; i++) {
487                         vlandev = vlan_group_get_device(grp, i);
488                         if (!vlandev)
489                                 continue;
490
491                         /* unregistration of last vlan destroys group, abort
492                          * afterwards */
493                         if (grp->nr_vlans == 1)
494                                 i = VLAN_GROUP_ARRAY_LEN;
495
496                         unregister_vlan_dev(vlandev);
497                 }
498                 break;
499         }
500
501 out:
502         return NOTIFY_DONE;
503 }
504
505 static struct notifier_block vlan_notifier_block __read_mostly = {
506         .notifier_call = vlan_device_event,
507 };
508
509 /*
510  *      VLAN IOCTL handler.
511  *      o execute requested action or pass command to the device driver
512  *   arg is really a struct vlan_ioctl_args __user *.
513  */
514 static int vlan_ioctl_handler(struct net *net, void __user *arg)
515 {
516         int err;
517         unsigned short vid = 0;
518         struct vlan_ioctl_args args;
519         struct net_device *dev = NULL;
520
521         if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
522                 return -EFAULT;
523
524         /* Null terminate this sucker, just in case. */
525         args.device1[23] = 0;
526         args.u.device2[23] = 0;
527
528         rtnl_lock();
529
530         switch (args.cmd) {
531         case SET_VLAN_INGRESS_PRIORITY_CMD:
532         case SET_VLAN_EGRESS_PRIORITY_CMD:
533         case SET_VLAN_FLAG_CMD:
534         case ADD_VLAN_CMD:
535         case DEL_VLAN_CMD:
536         case GET_VLAN_REALDEV_NAME_CMD:
537         case GET_VLAN_VID_CMD:
538                 err = -ENODEV;
539                 dev = __dev_get_by_name(net, args.device1);
540                 if (!dev)
541                         goto out;
542
543                 err = -EINVAL;
544                 if (args.cmd != ADD_VLAN_CMD &&
545                     !(dev->priv_flags & IFF_802_1Q_VLAN))
546                         goto out;
547         }
548
549         switch (args.cmd) {
550         case SET_VLAN_INGRESS_PRIORITY_CMD:
551                 err = -EPERM;
552                 if (!capable(CAP_NET_ADMIN))
553                         break;
554                 vlan_dev_set_ingress_priority(dev,
555                                               args.u.skb_priority,
556                                               args.vlan_qos);
557                 err = 0;
558                 break;
559
560         case SET_VLAN_EGRESS_PRIORITY_CMD:
561                 err = -EPERM;
562                 if (!capable(CAP_NET_ADMIN))
563                         break;
564                 err = vlan_dev_set_egress_priority(dev,
565                                                    args.u.skb_priority,
566                                                    args.vlan_qos);
567                 break;
568
569         case SET_VLAN_FLAG_CMD:
570                 err = -EPERM;
571                 if (!capable(CAP_NET_ADMIN))
572                         break;
573                 err = vlan_dev_set_vlan_flag(dev,
574                                              args.u.flag,
575                                              args.vlan_qos);
576                 break;
577
578         case SET_VLAN_NAME_TYPE_CMD:
579                 err = -EPERM;
580                 if (!capable(CAP_NET_ADMIN))
581                         break;
582                 if ((args.u.name_type >= 0) &&
583                     (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
584                         struct vlan_net *vn;
585
586                         vn = net_generic(net, vlan_net_id);
587                         vn->name_type = args.u.name_type;
588                         err = 0;
589                 } else {
590                         err = -EINVAL;
591                 }
592                 break;
593
594         case ADD_VLAN_CMD:
595                 err = -EPERM;
596                 if (!capable(CAP_NET_ADMIN))
597                         break;
598                 err = register_vlan_device(dev, args.u.VID);
599                 break;
600
601         case DEL_VLAN_CMD:
602                 err = -EPERM;
603                 if (!capable(CAP_NET_ADMIN))
604                         break;
605                 unregister_vlan_dev(dev);
606                 err = 0;
607                 break;
608
609         case GET_VLAN_REALDEV_NAME_CMD:
610                 err = 0;
611                 vlan_dev_get_realdev_name(dev, args.u.device2);
612                 if (copy_to_user(arg, &args,
613                                  sizeof(struct vlan_ioctl_args)))
614                         err = -EFAULT;
615                 break;
616
617         case GET_VLAN_VID_CMD:
618                 err = 0;
619                 vlan_dev_get_vid(dev, &vid);
620                 args.u.VID = vid;
621                 if (copy_to_user(arg, &args,
622                                  sizeof(struct vlan_ioctl_args)))
623                       err = -EFAULT;
624                 break;
625
626         default:
627                 err = -EOPNOTSUPP;
628                 break;
629         }
630 out:
631         rtnl_unlock();
632         return err;
633 }
634
635 static int vlan_init_net(struct net *net)
636 {
637         int err;
638         struct vlan_net *vn;
639
640         err = -ENOMEM;
641         vn = kzalloc(sizeof(struct vlan_net), GFP_KERNEL);
642         if (vn == NULL)
643                 goto err_alloc;
644
645         err = net_assign_generic(net, vlan_net_id, vn);
646         if (err < 0)
647                 goto err_assign;
648
649         vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
650
651         err = vlan_proc_init(net);
652         if (err < 0)
653                 goto err_proc;
654
655         return 0;
656
657 err_proc:
658         /* nothing */
659 err_assign:
660         kfree(vn);
661 err_alloc:
662         return err;
663 }
664
665 static void vlan_exit_net(struct net *net)
666 {
667         struct vlan_net *vn;
668
669         vn = net_generic(net, vlan_net_id);
670         rtnl_kill_links(net, &vlan_link_ops);
671         vlan_proc_cleanup(net);
672         kfree(vn);
673 }
674
675 static struct pernet_operations vlan_net_ops = {
676         .init = vlan_init_net,
677         .exit = vlan_exit_net,
678 };
679
680 static int __init vlan_proto_init(void)
681 {
682         int err;
683
684         pr_info("%s v%s %s\n", vlan_fullname, vlan_version, vlan_copyright);
685         pr_info("All bugs added by %s\n", vlan_buggyright);
686
687         err = register_pernet_gen_device(&vlan_net_id, &vlan_net_ops);
688         if (err < 0)
689                 goto err0;
690
691         err = register_netdevice_notifier(&vlan_notifier_block);
692         if (err < 0)
693                 goto err2;
694
695         err = vlan_netlink_init();
696         if (err < 0)
697                 goto err3;
698
699         dev_add_pack(&vlan_packet_type);
700         vlan_ioctl_set(vlan_ioctl_handler);
701         return 0;
702
703 err3:
704         unregister_netdevice_notifier(&vlan_notifier_block);
705 err2:
706         unregister_pernet_gen_device(vlan_net_id, &vlan_net_ops);
707 err0:
708         return err;
709 }
710
711 static void __exit vlan_cleanup_module(void)
712 {
713         unsigned int i;
714
715         vlan_ioctl_set(NULL);
716         vlan_netlink_fini();
717
718         unregister_netdevice_notifier(&vlan_notifier_block);
719
720         dev_remove_pack(&vlan_packet_type);
721
722         /* This table must be empty if there are no module references left. */
723         for (i = 0; i < VLAN_GRP_HASH_SIZE; i++)
724                 BUG_ON(!hlist_empty(&vlan_group_hash[i]));
725
726         unregister_pernet_gen_device(vlan_net_id, &vlan_net_ops);
727
728         synchronize_net();
729 }
730
731 module_init(vlan_proto_init);
732 module_exit(vlan_cleanup_module);
733
734 MODULE_LICENSE("GPL");
735 MODULE_VERSION(DRV_VERSION);