flex_array: avoid divisions when accessing elements
[linux-2.6/libata-dev.git] / net / 8021q / vlan.c
blobb2274d1fd605b90cdeeb14a72cc909acd9e55001
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 <linux/capability.h>
22 #include <linux/module.h>
23 #include <linux/netdevice.h>
24 #include <linux/skbuff.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/rculist.h>
28 #include <net/p8022.h>
29 #include <net/arp.h>
30 #include <linux/rtnetlink.h>
31 #include <linux/notifier.h>
32 #include <net/rtnetlink.h>
33 #include <net/net_namespace.h>
34 #include <net/netns/generic.h>
35 #include <asm/uaccess.h>
37 #include <linux/if_vlan.h>
38 #include "vlan.h"
39 #include "vlanproc.h"
41 #define DRV_VERSION "1.8"
43 /* Global VLAN variables */
45 int vlan_net_id __read_mostly;
47 const char vlan_fullname[] = "802.1Q VLAN Support";
48 const char vlan_version[] = DRV_VERSION;
49 static const char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
50 static const char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";
52 /* End of global variables definitions. */
54 static void vlan_group_free(struct vlan_group *grp)
56 int i;
58 for (i = 0; i < VLAN_GROUP_ARRAY_SPLIT_PARTS; i++)
59 kfree(grp->vlan_devices_arrays[i]);
60 kfree(grp);
63 static struct vlan_group *vlan_group_alloc(struct net_device *real_dev)
65 struct vlan_group *grp;
67 grp = kzalloc(sizeof(struct vlan_group), GFP_KERNEL);
68 if (!grp)
69 return NULL;
71 grp->real_dev = real_dev;
72 return grp;
75 static int vlan_group_prealloc_vid(struct vlan_group *vg, u16 vlan_id)
77 struct net_device **array;
78 unsigned int size;
80 ASSERT_RTNL();
82 array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
83 if (array != NULL)
84 return 0;
86 size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
87 array = kzalloc(size, GFP_KERNEL);
88 if (array == NULL)
89 return -ENOBUFS;
91 vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN] = array;
92 return 0;
95 static void vlan_rcu_free(struct rcu_head *rcu)
97 vlan_group_free(container_of(rcu, struct vlan_group, rcu));
100 void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
102 struct vlan_dev_info *vlan = vlan_dev_info(dev);
103 struct net_device *real_dev = vlan->real_dev;
104 const struct net_device_ops *ops = real_dev->netdev_ops;
105 struct vlan_group *grp;
106 u16 vlan_id = vlan->vlan_id;
108 ASSERT_RTNL();
110 grp = rtnl_dereference(real_dev->vlgrp);
111 BUG_ON(!grp);
113 /* Take it out of our own structures, but be sure to interlock with
114 * HW accelerating devices or SW vlan input packet processing if
115 * VLAN is not 0 (leave it there for 802.1p).
117 if (vlan_id && (real_dev->features & NETIF_F_HW_VLAN_FILTER))
118 ops->ndo_vlan_rx_kill_vid(real_dev, vlan_id);
120 grp->nr_vlans--;
122 if (vlan->flags & VLAN_FLAG_GVRP)
123 vlan_gvrp_request_leave(dev);
125 vlan_group_set_device(grp, vlan_id, NULL);
126 /* Because unregister_netdevice_queue() makes sure at least one rcu
127 * grace period is respected before device freeing,
128 * we dont need to call synchronize_net() here.
130 unregister_netdevice_queue(dev, head);
132 /* If the group is now empty, kill off the group. */
133 if (grp->nr_vlans == 0) {
134 vlan_gvrp_uninit_applicant(real_dev);
136 rcu_assign_pointer(real_dev->vlgrp, NULL);
137 if (ops->ndo_vlan_rx_register)
138 ops->ndo_vlan_rx_register(real_dev, NULL);
140 /* Free the group, after all cpu's are done. */
141 call_rcu(&grp->rcu, vlan_rcu_free);
144 /* Get rid of the vlan's reference to real_dev */
145 dev_put(real_dev);
148 int vlan_check_real_dev(struct net_device *real_dev, u16 vlan_id)
150 const char *name = real_dev->name;
151 const struct net_device_ops *ops = real_dev->netdev_ops;
153 if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
154 pr_info("8021q: VLANs not supported on %s\n", name);
155 return -EOPNOTSUPP;
158 if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
159 (!ops->ndo_vlan_rx_add_vid || !ops->ndo_vlan_rx_kill_vid)) {
160 pr_info("8021q: Device %s has buggy VLAN hw accel\n", name);
161 return -EOPNOTSUPP;
164 if (vlan_find_dev(real_dev, vlan_id) != NULL)
165 return -EEXIST;
167 return 0;
170 int register_vlan_dev(struct net_device *dev)
172 struct vlan_dev_info *vlan = vlan_dev_info(dev);
173 struct net_device *real_dev = vlan->real_dev;
174 const struct net_device_ops *ops = real_dev->netdev_ops;
175 u16 vlan_id = vlan->vlan_id;
176 struct vlan_group *grp, *ngrp = NULL;
177 int err;
179 grp = rtnl_dereference(real_dev->vlgrp);
180 if (!grp) {
181 ngrp = grp = vlan_group_alloc(real_dev);
182 if (!grp)
183 return -ENOBUFS;
184 err = vlan_gvrp_init_applicant(real_dev);
185 if (err < 0)
186 goto out_free_group;
189 err = vlan_group_prealloc_vid(grp, vlan_id);
190 if (err < 0)
191 goto out_uninit_applicant;
193 err = register_netdevice(dev);
194 if (err < 0)
195 goto out_uninit_applicant;
197 /* Account for reference in struct vlan_dev_info */
198 dev_hold(real_dev);
200 netif_stacked_transfer_operstate(real_dev, dev);
201 linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
203 /* So, got the sucker initialized, now lets place
204 * it into our local structure.
206 vlan_group_set_device(grp, vlan_id, dev);
207 grp->nr_vlans++;
209 if (ngrp) {
210 if (ops->ndo_vlan_rx_register)
211 ops->ndo_vlan_rx_register(real_dev, ngrp);
212 rcu_assign_pointer(real_dev->vlgrp, ngrp);
214 if (real_dev->features & NETIF_F_HW_VLAN_FILTER)
215 ops->ndo_vlan_rx_add_vid(real_dev, vlan_id);
217 return 0;
219 out_uninit_applicant:
220 if (ngrp)
221 vlan_gvrp_uninit_applicant(real_dev);
222 out_free_group:
223 if (ngrp) {
224 /* Free the group, after all cpu's are done. */
225 call_rcu(&ngrp->rcu, vlan_rcu_free);
227 return err;
230 /* Attach a VLAN device to a mac address (ie Ethernet Card).
231 * Returns 0 if the device was created or a negative error code otherwise.
233 static int register_vlan_device(struct net_device *real_dev, u16 vlan_id)
235 struct net_device *new_dev;
236 struct net *net = dev_net(real_dev);
237 struct vlan_net *vn = net_generic(net, vlan_net_id);
238 char name[IFNAMSIZ];
239 int err;
241 if (vlan_id >= VLAN_VID_MASK)
242 return -ERANGE;
244 err = vlan_check_real_dev(real_dev, vlan_id);
245 if (err < 0)
246 return err;
248 /* Gotta set up the fields for the device. */
249 switch (vn->name_type) {
250 case VLAN_NAME_TYPE_RAW_PLUS_VID:
251 /* name will look like: eth1.0005 */
252 snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, vlan_id);
253 break;
254 case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
255 /* Put our vlan.VID in the name.
256 * Name will look like: vlan5
258 snprintf(name, IFNAMSIZ, "vlan%i", vlan_id);
259 break;
260 case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
261 /* Put our vlan.VID in the name.
262 * Name will look like: eth0.5
264 snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, vlan_id);
265 break;
266 case VLAN_NAME_TYPE_PLUS_VID:
267 /* Put our vlan.VID in the name.
268 * Name will look like: vlan0005
270 default:
271 snprintf(name, IFNAMSIZ, "vlan%.4i", vlan_id);
274 new_dev = alloc_netdev(sizeof(struct vlan_dev_info), name, vlan_setup);
276 if (new_dev == NULL)
277 return -ENOBUFS;
279 dev_net_set(new_dev, net);
280 /* need 4 bytes for extra VLAN header info,
281 * hope the underlying device can handle it.
283 new_dev->mtu = real_dev->mtu;
285 vlan_dev_info(new_dev)->vlan_id = vlan_id;
286 vlan_dev_info(new_dev)->real_dev = real_dev;
287 vlan_dev_info(new_dev)->dent = NULL;
288 vlan_dev_info(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
290 new_dev->rtnl_link_ops = &vlan_link_ops;
291 err = register_vlan_dev(new_dev);
292 if (err < 0)
293 goto out_free_newdev;
295 return 0;
297 out_free_newdev:
298 free_netdev(new_dev);
299 return err;
302 static void vlan_sync_address(struct net_device *dev,
303 struct net_device *vlandev)
305 struct vlan_dev_info *vlan = vlan_dev_info(vlandev);
307 /* May be called without an actual change */
308 if (!compare_ether_addr(vlan->real_dev_addr, dev->dev_addr))
309 return;
311 /* vlan address was different from the old address and is equal to
312 * the new address */
313 if (compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
314 !compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
315 dev_uc_del(dev, vlandev->dev_addr);
317 /* vlan address was equal to the old address and is different from
318 * the new address */
319 if (!compare_ether_addr(vlandev->dev_addr, vlan->real_dev_addr) &&
320 compare_ether_addr(vlandev->dev_addr, dev->dev_addr))
321 dev_uc_add(dev, vlandev->dev_addr);
323 memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
326 static void vlan_transfer_features(struct net_device *dev,
327 struct net_device *vlandev)
329 vlandev->gso_max_size = dev->gso_max_size;
331 if (dev->features & NETIF_F_HW_VLAN_TX)
332 vlandev->hard_header_len = dev->hard_header_len;
333 else
334 vlandev->hard_header_len = dev->hard_header_len + VLAN_HLEN;
336 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
337 vlandev->fcoe_ddp_xid = dev->fcoe_ddp_xid;
338 #endif
340 netdev_update_features(vlandev);
343 static void __vlan_device_event(struct net_device *dev, unsigned long event)
345 switch (event) {
346 case NETDEV_CHANGENAME:
347 vlan_proc_rem_dev(dev);
348 if (vlan_proc_add_dev(dev) < 0)
349 pr_warning("8021q: failed to change proc name for %s\n",
350 dev->name);
351 break;
352 case NETDEV_REGISTER:
353 if (vlan_proc_add_dev(dev) < 0)
354 pr_warning("8021q: failed to add proc entry for %s\n",
355 dev->name);
356 break;
357 case NETDEV_UNREGISTER:
358 vlan_proc_rem_dev(dev);
359 break;
363 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
364 void *ptr)
366 struct net_device *dev = ptr;
367 struct vlan_group *grp;
368 int i, flgs;
369 struct net_device *vlandev;
370 struct vlan_dev_info *vlan;
371 LIST_HEAD(list);
373 if (is_vlan_dev(dev))
374 __vlan_device_event(dev, event);
376 if ((event == NETDEV_UP) &&
377 (dev->features & NETIF_F_HW_VLAN_FILTER) &&
378 dev->netdev_ops->ndo_vlan_rx_add_vid) {
379 pr_info("8021q: adding VLAN 0 to HW filter on device %s\n",
380 dev->name);
381 dev->netdev_ops->ndo_vlan_rx_add_vid(dev, 0);
384 grp = rtnl_dereference(dev->vlgrp);
385 if (!grp)
386 goto out;
388 /* It is OK that we do not hold the group lock right now,
389 * as we run under the RTNL lock.
392 switch (event) {
393 case NETDEV_CHANGE:
394 /* Propagate real device state to vlan devices */
395 for (i = 0; i < VLAN_N_VID; i++) {
396 vlandev = vlan_group_get_device(grp, i);
397 if (!vlandev)
398 continue;
400 netif_stacked_transfer_operstate(dev, vlandev);
402 break;
404 case NETDEV_CHANGEADDR:
405 /* Adjust unicast filters on underlying device */
406 for (i = 0; i < VLAN_N_VID; i++) {
407 vlandev = vlan_group_get_device(grp, i);
408 if (!vlandev)
409 continue;
411 flgs = vlandev->flags;
412 if (!(flgs & IFF_UP))
413 continue;
415 vlan_sync_address(dev, vlandev);
417 break;
419 case NETDEV_CHANGEMTU:
420 for (i = 0; i < VLAN_N_VID; i++) {
421 vlandev = vlan_group_get_device(grp, i);
422 if (!vlandev)
423 continue;
425 if (vlandev->mtu <= dev->mtu)
426 continue;
428 dev_set_mtu(vlandev, dev->mtu);
430 break;
432 case NETDEV_FEAT_CHANGE:
433 /* Propagate device features to underlying device */
434 for (i = 0; i < VLAN_N_VID; i++) {
435 vlandev = vlan_group_get_device(grp, i);
436 if (!vlandev)
437 continue;
439 vlan_transfer_features(dev, vlandev);
442 break;
444 case NETDEV_DOWN:
445 /* Put all VLANs for this dev in the down state too. */
446 for (i = 0; i < VLAN_N_VID; i++) {
447 vlandev = vlan_group_get_device(grp, i);
448 if (!vlandev)
449 continue;
451 flgs = vlandev->flags;
452 if (!(flgs & IFF_UP))
453 continue;
455 vlan = vlan_dev_info(vlandev);
456 if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
457 dev_change_flags(vlandev, flgs & ~IFF_UP);
458 netif_stacked_transfer_operstate(dev, vlandev);
460 break;
462 case NETDEV_UP:
463 /* Put all VLANs for this dev in the up state too. */
464 for (i = 0; i < VLAN_N_VID; i++) {
465 vlandev = vlan_group_get_device(grp, i);
466 if (!vlandev)
467 continue;
469 flgs = vlandev->flags;
470 if (flgs & IFF_UP)
471 continue;
473 vlan = vlan_dev_info(vlandev);
474 if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
475 dev_change_flags(vlandev, flgs | IFF_UP);
476 netif_stacked_transfer_operstate(dev, vlandev);
478 break;
480 case NETDEV_UNREGISTER:
481 /* twiddle thumbs on netns device moves */
482 if (dev->reg_state != NETREG_UNREGISTERING)
483 break;
485 for (i = 0; i < VLAN_N_VID; i++) {
486 vlandev = vlan_group_get_device(grp, i);
487 if (!vlandev)
488 continue;
490 /* unregistration of last vlan destroys group, abort
491 * afterwards */
492 if (grp->nr_vlans == 1)
493 i = VLAN_N_VID;
495 unregister_vlan_dev(vlandev, &list);
497 unregister_netdevice_many(&list);
498 break;
500 case NETDEV_PRE_TYPE_CHANGE:
501 /* Forbid underlaying device to change its type. */
502 return NOTIFY_BAD;
504 case NETDEV_NOTIFY_PEERS:
505 case NETDEV_BONDING_FAILOVER:
506 /* Propagate to vlan devices */
507 for (i = 0; i < VLAN_N_VID; i++) {
508 vlandev = vlan_group_get_device(grp, i);
509 if (!vlandev)
510 continue;
512 call_netdevice_notifiers(event, vlandev);
514 break;
517 out:
518 return NOTIFY_DONE;
521 static struct notifier_block vlan_notifier_block __read_mostly = {
522 .notifier_call = vlan_device_event,
526 * VLAN IOCTL handler.
527 * o execute requested action or pass command to the device driver
528 * arg is really a struct vlan_ioctl_args __user *.
530 static int vlan_ioctl_handler(struct net *net, void __user *arg)
532 int err;
533 struct vlan_ioctl_args args;
534 struct net_device *dev = NULL;
536 if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
537 return -EFAULT;
539 /* Null terminate this sucker, just in case. */
540 args.device1[23] = 0;
541 args.u.device2[23] = 0;
543 rtnl_lock();
545 switch (args.cmd) {
546 case SET_VLAN_INGRESS_PRIORITY_CMD:
547 case SET_VLAN_EGRESS_PRIORITY_CMD:
548 case SET_VLAN_FLAG_CMD:
549 case ADD_VLAN_CMD:
550 case DEL_VLAN_CMD:
551 case GET_VLAN_REALDEV_NAME_CMD:
552 case GET_VLAN_VID_CMD:
553 err = -ENODEV;
554 dev = __dev_get_by_name(net, args.device1);
555 if (!dev)
556 goto out;
558 err = -EINVAL;
559 if (args.cmd != ADD_VLAN_CMD && !is_vlan_dev(dev))
560 goto out;
563 switch (args.cmd) {
564 case SET_VLAN_INGRESS_PRIORITY_CMD:
565 err = -EPERM;
566 if (!capable(CAP_NET_ADMIN))
567 break;
568 vlan_dev_set_ingress_priority(dev,
569 args.u.skb_priority,
570 args.vlan_qos);
571 err = 0;
572 break;
574 case SET_VLAN_EGRESS_PRIORITY_CMD:
575 err = -EPERM;
576 if (!capable(CAP_NET_ADMIN))
577 break;
578 err = vlan_dev_set_egress_priority(dev,
579 args.u.skb_priority,
580 args.vlan_qos);
581 break;
583 case SET_VLAN_FLAG_CMD:
584 err = -EPERM;
585 if (!capable(CAP_NET_ADMIN))
586 break;
587 err = vlan_dev_change_flags(dev,
588 args.vlan_qos ? args.u.flag : 0,
589 args.u.flag);
590 break;
592 case SET_VLAN_NAME_TYPE_CMD:
593 err = -EPERM;
594 if (!capable(CAP_NET_ADMIN))
595 break;
596 if ((args.u.name_type >= 0) &&
597 (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
598 struct vlan_net *vn;
600 vn = net_generic(net, vlan_net_id);
601 vn->name_type = args.u.name_type;
602 err = 0;
603 } else {
604 err = -EINVAL;
606 break;
608 case ADD_VLAN_CMD:
609 err = -EPERM;
610 if (!capable(CAP_NET_ADMIN))
611 break;
612 err = register_vlan_device(dev, args.u.VID);
613 break;
615 case DEL_VLAN_CMD:
616 err = -EPERM;
617 if (!capable(CAP_NET_ADMIN))
618 break;
619 unregister_vlan_dev(dev, NULL);
620 err = 0;
621 break;
623 case GET_VLAN_REALDEV_NAME_CMD:
624 err = 0;
625 vlan_dev_get_realdev_name(dev, args.u.device2);
626 if (copy_to_user(arg, &args,
627 sizeof(struct vlan_ioctl_args)))
628 err = -EFAULT;
629 break;
631 case GET_VLAN_VID_CMD:
632 err = 0;
633 args.u.VID = vlan_dev_vlan_id(dev);
634 if (copy_to_user(arg, &args,
635 sizeof(struct vlan_ioctl_args)))
636 err = -EFAULT;
637 break;
639 default:
640 err = -EOPNOTSUPP;
641 break;
643 out:
644 rtnl_unlock();
645 return err;
648 static int __net_init vlan_init_net(struct net *net)
650 struct vlan_net *vn = net_generic(net, vlan_net_id);
651 int err;
653 vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
655 err = vlan_proc_init(net);
657 return err;
660 static void __net_exit vlan_exit_net(struct net *net)
662 vlan_proc_cleanup(net);
665 static struct pernet_operations vlan_net_ops = {
666 .init = vlan_init_net,
667 .exit = vlan_exit_net,
668 .id = &vlan_net_id,
669 .size = sizeof(struct vlan_net),
672 static int __init vlan_proto_init(void)
674 int err;
676 pr_info("%s v%s %s\n", vlan_fullname, vlan_version, vlan_copyright);
677 pr_info("All bugs added by %s\n", vlan_buggyright);
679 err = register_pernet_subsys(&vlan_net_ops);
680 if (err < 0)
681 goto err0;
683 err = register_netdevice_notifier(&vlan_notifier_block);
684 if (err < 0)
685 goto err2;
687 err = vlan_gvrp_init();
688 if (err < 0)
689 goto err3;
691 err = vlan_netlink_init();
692 if (err < 0)
693 goto err4;
695 vlan_ioctl_set(vlan_ioctl_handler);
696 return 0;
698 err4:
699 vlan_gvrp_uninit();
700 err3:
701 unregister_netdevice_notifier(&vlan_notifier_block);
702 err2:
703 unregister_pernet_subsys(&vlan_net_ops);
704 err0:
705 return err;
708 static void __exit vlan_cleanup_module(void)
710 vlan_ioctl_set(NULL);
711 vlan_netlink_fini();
713 unregister_netdevice_notifier(&vlan_notifier_block);
715 unregister_pernet_subsys(&vlan_net_ops);
716 rcu_barrier(); /* Wait for completion of call_rcu()'s */
718 vlan_gvrp_uninit();
721 module_init(vlan_proto_init);
722 module_exit(vlan_cleanup_module);
724 MODULE_LICENSE("GPL");
725 MODULE_VERSION(DRV_VERSION);