rcu: split list.h and move rcu-protected lists into rculist.h
[linux-2.6/mini2440.git] / net / 8021q / vlan.c
blobe7ddbfa0e02f4a1e24e7d26947aa152506aa401e
1 /*
2 * INET 802.1Q VLAN
3 * Ethernet-type device handling.
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
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>
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.
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>
38 #include <linux/if_vlan.h>
39 #include "vlan.h"
40 #include "vlanproc.h"
42 #define DRV_VERSION "1.8"
44 /* Global VLAN variables */
46 int vlan_net_id;
48 /* Our listing of VLAN group(s) */
49 static struct hlist_head vlan_group_hash[VLAN_GRP_HASH_SIZE];
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>";
56 static struct packet_type vlan_packet_type = {
57 .type = __constant_htons(ETH_P_8021Q),
58 .func = vlan_skb_recv, /* VLAN receive method */
61 /* End of global variables definitions. */
63 static inline unsigned int vlan_grp_hashfn(unsigned int idx)
65 return ((idx >> VLAN_GRP_HASH_SHIFT) ^ idx) & VLAN_GRP_HASH_MASK;
68 /* Must be invoked with RCU read lock (no preempt) */
69 static struct vlan_group *__vlan_find_group(struct net_device *real_dev)
71 struct vlan_group *grp;
72 struct hlist_node *n;
73 int hash = vlan_grp_hashfn(real_dev->ifindex);
75 hlist_for_each_entry_rcu(grp, n, &vlan_group_hash[hash], hlist) {
76 if (grp->real_dev == real_dev)
77 return grp;
80 return NULL;
83 /* Find the protocol handler. Assumes VID < VLAN_VID_MASK.
85 * Must be invoked with RCU read lock (no preempt)
87 struct net_device *__find_vlan_dev(struct net_device *real_dev,
88 unsigned short VID)
90 struct vlan_group *grp = __vlan_find_group(real_dev);
92 if (grp)
93 return vlan_group_get_device(grp, VID);
95 return NULL;
98 static void vlan_group_free(struct vlan_group *grp)
100 int i;
102 for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
103 kfree(grp->vlan_devices_arrays[i]);
104 kfree(grp);
107 static struct vlan_group *vlan_group_alloc(struct net_device *real_dev)
109 struct vlan_group *grp;
111 grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL);
112 if (!grp)
113 return NULL;
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;
121 static int vlan_group_prealloc_vid(struct vlan_group *vg, int vid)
123 struct net_device **array;
124 unsigned int size;
126 ASSERT_RTNL();
128 array = vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN];
129 if (array != NULL)
130 return 0;
132 size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
133 array = kzalloc(size, GFP_KERNEL);
134 if (array == NULL)
135 return -ENOBUFS;
137 vg->vlan_devices_arrays[vid / VLAN_GROUP_ARRAY_PART_LEN] = array;
138 return 0;
141 static void vlan_rcu_free(struct rcu_head *rcu)
143 vlan_group_free(container_of(rcu, struct vlan_group, rcu));
146 void unregister_vlan_dev(struct net_device *dev)
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;
153 ASSERT_RTNL();
155 grp = __vlan_find_group(real_dev);
156 BUG_ON(!grp);
158 /* Take it out of our own structures, but be sure to interlock with
159 * HW accelerating devices or SW vlan input packet processing.
161 if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
162 real_dev->vlan_rx_kill_vid(real_dev, vlan_id);
164 vlan_group_set_device(grp, vlan_id, NULL);
165 grp->nr_vlans--;
167 synchronize_net();
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);
174 hlist_del_rcu(&grp->hlist);
176 /* Free the group, after all cpu's are done. */
177 call_rcu(&grp->rcu, vlan_rcu_free);
180 /* Get rid of the vlan's reference to real_dev */
181 dev_put(real_dev);
183 unregister_netdevice(dev);
186 static void vlan_transfer_operstate(const struct net_device *dev,
187 struct net_device *vlandev)
189 /* Have to respect userspace enforced dormant state
190 * of real device, also must allow supplicant running
191 * on VLAN device
193 if (dev->operstate == IF_OPER_DORMANT)
194 netif_dormant_on(vlandev);
195 else
196 netif_dormant_off(vlandev);
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);
207 int vlan_check_real_dev(struct net_device *real_dev, unsigned short vlan_id)
209 char *name = real_dev->name;
211 if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
212 pr_info("8021q: VLANs not supported on %s\n", name);
213 return -EOPNOTSUPP;
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;
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;
228 /* The real device must be up and operating in order to
229 * assosciate a VLAN device with it.
231 if (!(real_dev->flags & IFF_UP))
232 return -ENETDOWN;
234 if (__find_vlan_dev(real_dev, vlan_id) != NULL)
235 return -EEXIST;
237 return 0;
240 int register_vlan_dev(struct net_device *dev)
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;
248 grp = __vlan_find_group(real_dev);
249 if (!grp) {
250 ngrp = grp = vlan_group_alloc(real_dev);
251 if (!grp)
252 return -ENOBUFS;
255 err = vlan_group_prealloc_vid(grp, vlan_id);
256 if (err < 0)
257 goto out_free_group;
259 err = register_netdevice(dev);
260 if (err < 0)
261 goto out_free_group;
263 /* Account for reference in struct vlan_dev_info */
264 dev_hold(real_dev);
266 vlan_transfer_operstate(real_dev, dev);
267 linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
269 /* So, got the sucker initialized, now lets place
270 * it into our local structure.
272 vlan_group_set_device(grp, vlan_id, dev);
273 grp->nr_vlans++;
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);
280 return 0;
282 out_free_group:
283 if (ngrp)
284 vlan_group_free(ngrp);
285 return err;
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.
291 static int register_vlan_device(struct net_device *real_dev,
292 unsigned short VLAN_ID)
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;
300 if (VLAN_ID >= VLAN_VID_MASK)
301 return -ERANGE;
303 err = vlan_check_real_dev(real_dev, VLAN_ID);
304 if (err < 0)
305 return err;
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
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
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
329 default:
330 snprintf(name, IFNAMSIZ, "vlan%.4i", VLAN_ID);
333 new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name,
334 vlan_setup);
336 if (new_dev == NULL)
337 return -ENOBUFS;
339 dev_net_set(new_dev, net);
340 /* need 4 bytes for extra VLAN header info,
341 * hope the underlying device can handle it.
343 new_dev->mtu = real_dev->mtu;
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;
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;
355 return 0;
357 out_free_newdev:
358 free_netdev(new_dev);
359 return err;
362 static void vlan_sync_address(struct net_device *dev,
363 struct net_device *vlandev)
365 struct vlan_dev_info *vlan = vlan_dev_info(vlandev);
367 /* May be called without an actual change */
368 if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr))
369 return;
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);
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);
383 memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
386 static void __vlan_device_event(struct net_device *dev, unsigned long event)
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;
406 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
407 void *ptr)
409 struct net_device *dev = ptr;
410 struct vlan_group *grp;
411 int i, flgs;
412 struct net_device *vlandev;
414 if (is_vlan_dev(dev)) {
415 __vlan_device_event(dev, event);
416 goto out;
419 grp = __vlan_find_group(dev);
420 if (!grp)
421 goto out;
423 /* It is OK that we do not hold the group lock right now,
424 * as we run under the RTNL lock.
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;
435 vlan_transfer_operstate(dev, vlandev);
437 break;
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;
446 flgs = vlandev->flags;
447 if (!(flgs & IFF_UP))
448 continue;
450 vlan_sync_address(dev, vlandev);
452 break;
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;
461 flgs = vlandev->flags;
462 if (!(flgs & IFF_UP))
463 continue;
465 dev_change_flags(vlandev, flgs & ~IFF_UP);
467 break;
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;
476 flgs = vlandev->flags;
477 if (flgs & IFF_UP)
478 continue;
480 dev_change_flags(vlandev, flgs | IFF_UP);
482 break;
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;
491 /* unregistration of last vlan destroys group, abort
492 * afterwards */
493 if (grp->nr_vlans == 1)
494 i = VLAN_GROUP_ARRAY_LEN;
496 unregister_vlan_dev(vlandev);
498 break;
501 out:
502 return NOTIFY_DONE;
505 static struct notifier_block vlan_notifier_block __read_mostly = {
506 .notifier_call = vlan_device_event,
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 *.
514 static int vlan_ioctl_handler(struct net *net, void __user *arg)
516 int err;
517 unsigned short vid = 0;
518 struct vlan_ioctl_args args;
519 struct net_device *dev = NULL;
521 if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
522 return -EFAULT;
524 /* Null terminate this sucker, just in case. */
525 args.device1[23] = 0;
526 args.u.device2[23] = 0;
528 rtnl_lock();
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;
543 err = -EINVAL;
544 if (args.cmd != ADD_VLAN_CMD &&
545 !(dev->priv_flags & IFF_802_1Q_VLAN))
546 goto out;
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;
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;
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;
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;
586 vn = net_generic(net, vlan_net_id);
587 vn->name_type = args.u.name_type;
588 err = 0;
589 } else {
590 err = -EINVAL;
592 break;
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;
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;
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;
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;
626 default:
627 err = -EOPNOTSUPP;
628 break;
630 out:
631 rtnl_unlock();
632 return err;
635 static int vlan_init_net(struct net *net)
637 int err;
638 struct vlan_net *vn;
640 err = -ENOMEM;
641 vn = kzalloc(sizeof(struct vlan_net), GFP_KERNEL);
642 if (vn == NULL)
643 goto err_alloc;
645 err = net_assign_generic(net, vlan_net_id, vn);
646 if (err < 0)
647 goto err_assign;
649 vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
651 err = vlan_proc_init(net);
652 if (err < 0)
653 goto err_proc;
655 return 0;
657 err_proc:
658 /* nothing */
659 err_assign:
660 kfree(vn);
661 err_alloc:
662 return err;
665 static void vlan_exit_net(struct net *net)
667 struct vlan_net *vn;
669 vn = net_generic(net, vlan_net_id);
670 rtnl_kill_links(net, &vlan_link_ops);
671 vlan_proc_cleanup(net);
672 kfree(vn);
675 static struct pernet_operations vlan_net_ops = {
676 .init = vlan_init_net,
677 .exit = vlan_exit_net,
680 static int __init vlan_proto_init(void)
682 int err;
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);
687 err = register_pernet_gen_device(&vlan_net_id, &vlan_net_ops);
688 if (err < 0)
689 goto err0;
691 err = register_netdevice_notifier(&vlan_notifier_block);
692 if (err < 0)
693 goto err2;
695 err = vlan_netlink_init();
696 if (err < 0)
697 goto err3;
699 dev_add_pack(&vlan_packet_type);
700 vlan_ioctl_set(vlan_ioctl_handler);
701 return 0;
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;
711 static void __exit vlan_cleanup_module(void)
713 unsigned int i;
715 vlan_ioctl_set(NULL);
716 vlan_netlink_fini();
718 unregister_netdevice_notifier(&vlan_notifier_block);
720 dev_remove_pack(&vlan_packet_type);
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]));
726 unregister_pernet_gen_device(vlan_net_id, &vlan_net_ops);
728 synchronize_net();
731 module_init(vlan_proto_init);
732 module_exit(vlan_cleanup_module);
734 MODULE_LICENSE("GPL");
735 MODULE_VERSION(DRV_VERSION);