netpoll: use GFP_ATOMIC in slave_enable_netpoll() and __netpoll_setup()
[linux-3.10.git] / 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23 #include <linux/capability.h>
24 #include <linux/module.h>
25 #include <linux/netdevice.h>
26 #include <linux/skbuff.h>
27 #include <linux/slab.h>
28 #include <linux/init.h>
29 #include <linux/rculist.h>
30 #include <net/p8022.h>
31 #include <net/arp.h>
32 #include <linux/rtnetlink.h>
33 #include <linux/notifier.h>
34 #include <net/rtnetlink.h>
35 #include <net/net_namespace.h>
36 #include <net/netns/generic.h>
37 #include <asm/uaccess.h>
38
39 #include <linux/if_vlan.h>
40 #include "vlan.h"
41 #include "vlanproc.h"
42
43 #define DRV_VERSION "1.8"
44
45 /* Global VLAN variables */
46
47 int vlan_net_id __read_mostly;
48
49 const char vlan_fullname[] = "802.1Q VLAN Support";
50 const char vlan_version[] = DRV_VERSION;
51
52 /* End of global variables definitions. */
53
54 static int vlan_group_prealloc_vid(struct vlan_group *vg, u16 vlan_id)
55 {
56         struct net_device **array;
57         unsigned int size;
58
59         ASSERT_RTNL();
60
61         array = vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN];
62         if (array != NULL)
63                 return 0;
64
65         size = sizeof(struct net_device *) * VLAN_GROUP_ARRAY_PART_LEN;
66         array = kzalloc(size, GFP_KERNEL);
67         if (array == NULL)
68                 return -ENOBUFS;
69
70         vg->vlan_devices_arrays[vlan_id / VLAN_GROUP_ARRAY_PART_LEN] = array;
71         return 0;
72 }
73
74 void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
75 {
76         struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
77         struct net_device *real_dev = vlan->real_dev;
78         struct vlan_info *vlan_info;
79         struct vlan_group *grp;
80         u16 vlan_id = vlan->vlan_id;
81
82         ASSERT_RTNL();
83
84         vlan_info = rtnl_dereference(real_dev->vlan_info);
85         BUG_ON(!vlan_info);
86
87         grp = &vlan_info->grp;
88
89         /* Take it out of our own structures, but be sure to interlock with
90          * HW accelerating devices or SW vlan input packet processing if
91          * VLAN is not 0 (leave it there for 802.1p).
92          */
93         if (vlan_id)
94                 vlan_vid_del(real_dev, vlan_id);
95
96         grp->nr_vlan_devs--;
97
98         if (vlan->flags & VLAN_FLAG_GVRP)
99                 vlan_gvrp_request_leave(dev);
100
101         vlan_group_set_device(grp, vlan_id, NULL);
102         /* Because unregister_netdevice_queue() makes sure at least one rcu
103          * grace period is respected before device freeing,
104          * we dont need to call synchronize_net() here.
105          */
106         unregister_netdevice_queue(dev, head);
107
108         if (grp->nr_vlan_devs == 0)
109                 vlan_gvrp_uninit_applicant(real_dev);
110
111         /* Get rid of the vlan's reference to real_dev */
112         dev_put(real_dev);
113 }
114
115 int vlan_check_real_dev(struct net_device *real_dev, u16 vlan_id)
116 {
117         const char *name = real_dev->name;
118         const struct net_device_ops *ops = real_dev->netdev_ops;
119
120         if (real_dev->features & NETIF_F_VLAN_CHALLENGED) {
121                 pr_info("VLANs not supported on %s\n", name);
122                 return -EOPNOTSUPP;
123         }
124
125         if ((real_dev->features & NETIF_F_HW_VLAN_FILTER) &&
126             (!ops->ndo_vlan_rx_add_vid || !ops->ndo_vlan_rx_kill_vid)) {
127                 pr_info("Device %s has buggy VLAN hw accel\n", name);
128                 return -EOPNOTSUPP;
129         }
130
131         if (vlan_find_dev(real_dev, vlan_id) != NULL)
132                 return -EEXIST;
133
134         return 0;
135 }
136
137 int register_vlan_dev(struct net_device *dev)
138 {
139         struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
140         struct net_device *real_dev = vlan->real_dev;
141         u16 vlan_id = vlan->vlan_id;
142         struct vlan_info *vlan_info;
143         struct vlan_group *grp;
144         int err;
145
146         err = vlan_vid_add(real_dev, vlan_id);
147         if (err)
148                 return err;
149
150         vlan_info = rtnl_dereference(real_dev->vlan_info);
151         /* vlan_info should be there now. vlan_vid_add took care of it */
152         BUG_ON(!vlan_info);
153
154         grp = &vlan_info->grp;
155         if (grp->nr_vlan_devs == 0) {
156                 err = vlan_gvrp_init_applicant(real_dev);
157                 if (err < 0)
158                         goto out_vid_del;
159         }
160
161         err = vlan_group_prealloc_vid(grp, vlan_id);
162         if (err < 0)
163                 goto out_uninit_applicant;
164
165         err = register_netdevice(dev);
166         if (err < 0)
167                 goto out_uninit_applicant;
168
169         /* Account for reference in struct vlan_dev_priv */
170         dev_hold(real_dev);
171
172         netif_stacked_transfer_operstate(real_dev, dev);
173         linkwatch_fire_event(dev); /* _MUST_ call rfc2863_policy() */
174
175         /* So, got the sucker initialized, now lets place
176          * it into our local structure.
177          */
178         vlan_group_set_device(grp, vlan_id, dev);
179         grp->nr_vlan_devs++;
180
181         return 0;
182
183 out_uninit_applicant:
184         if (grp->nr_vlan_devs == 0)
185                 vlan_gvrp_uninit_applicant(real_dev);
186 out_vid_del:
187         vlan_vid_del(real_dev, vlan_id);
188         return err;
189 }
190
191 /*  Attach a VLAN device to a mac address (ie Ethernet Card).
192  *  Returns 0 if the device was created or a negative error code otherwise.
193  */
194 static int register_vlan_device(struct net_device *real_dev, u16 vlan_id)
195 {
196         struct net_device *new_dev;
197         struct net *net = dev_net(real_dev);
198         struct vlan_net *vn = net_generic(net, vlan_net_id);
199         char name[IFNAMSIZ];
200         int err;
201
202         if (vlan_id >= VLAN_VID_MASK)
203                 return -ERANGE;
204
205         err = vlan_check_real_dev(real_dev, vlan_id);
206         if (err < 0)
207                 return err;
208
209         /* Gotta set up the fields for the device. */
210         switch (vn->name_type) {
211         case VLAN_NAME_TYPE_RAW_PLUS_VID:
212                 /* name will look like:  eth1.0005 */
213                 snprintf(name, IFNAMSIZ, "%s.%.4i", real_dev->name, vlan_id);
214                 break;
215         case VLAN_NAME_TYPE_PLUS_VID_NO_PAD:
216                 /* Put our vlan.VID in the name.
217                  * Name will look like:  vlan5
218                  */
219                 snprintf(name, IFNAMSIZ, "vlan%i", vlan_id);
220                 break;
221         case VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD:
222                 /* Put our vlan.VID in the name.
223                  * Name will look like:  eth0.5
224                  */
225                 snprintf(name, IFNAMSIZ, "%s.%i", real_dev->name, vlan_id);
226                 break;
227         case VLAN_NAME_TYPE_PLUS_VID:
228                 /* Put our vlan.VID in the name.
229                  * Name will look like:  vlan0005
230                  */
231         default:
232                 snprintf(name, IFNAMSIZ, "vlan%.4i", vlan_id);
233         }
234
235         new_dev = alloc_netdev(sizeof(struct vlan_dev_priv), name, vlan_setup);
236
237         if (new_dev == NULL)
238                 return -ENOBUFS;
239
240         dev_net_set(new_dev, net);
241         /* need 4 bytes for extra VLAN header info,
242          * hope the underlying device can handle it.
243          */
244         new_dev->mtu = real_dev->mtu;
245
246         vlan_dev_priv(new_dev)->vlan_id = vlan_id;
247         vlan_dev_priv(new_dev)->real_dev = real_dev;
248         vlan_dev_priv(new_dev)->dent = NULL;
249         vlan_dev_priv(new_dev)->flags = VLAN_FLAG_REORDER_HDR;
250
251         new_dev->rtnl_link_ops = &vlan_link_ops;
252         err = register_vlan_dev(new_dev);
253         if (err < 0)
254                 goto out_free_newdev;
255
256         return 0;
257
258 out_free_newdev:
259         free_netdev(new_dev);
260         return err;
261 }
262
263 static void vlan_sync_address(struct net_device *dev,
264                               struct net_device *vlandev)
265 {
266         struct vlan_dev_priv *vlan = vlan_dev_priv(vlandev);
267
268         /* May be called without an actual change */
269         if (ether_addr_equal(vlan->real_dev_addr, dev->dev_addr))
270                 return;
271
272         /* vlan address was different from the old address and is equal to
273          * the new address */
274         if (!ether_addr_equal(vlandev->dev_addr, vlan->real_dev_addr) &&
275             ether_addr_equal(vlandev->dev_addr, dev->dev_addr))
276                 dev_uc_del(dev, vlandev->dev_addr);
277
278         /* vlan address was equal to the old address and is different from
279          * the new address */
280         if (ether_addr_equal(vlandev->dev_addr, vlan->real_dev_addr) &&
281             !ether_addr_equal(vlandev->dev_addr, dev->dev_addr))
282                 dev_uc_add(dev, vlandev->dev_addr);
283
284         memcpy(vlan->real_dev_addr, dev->dev_addr, ETH_ALEN);
285 }
286
287 static void vlan_transfer_features(struct net_device *dev,
288                                    struct net_device *vlandev)
289 {
290         vlandev->gso_max_size = dev->gso_max_size;
291
292         if (dev->features & NETIF_F_HW_VLAN_TX)
293                 vlandev->hard_header_len = dev->hard_header_len;
294         else
295                 vlandev->hard_header_len = dev->hard_header_len + VLAN_HLEN;
296
297 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
298         vlandev->fcoe_ddp_xid = dev->fcoe_ddp_xid;
299 #endif
300
301         netdev_update_features(vlandev);
302 }
303
304 static void __vlan_device_event(struct net_device *dev, unsigned long event)
305 {
306         switch (event) {
307         case NETDEV_CHANGENAME:
308                 vlan_proc_rem_dev(dev);
309                 if (vlan_proc_add_dev(dev) < 0)
310                         pr_warn("failed to change proc name for %s\n",
311                                 dev->name);
312                 break;
313         case NETDEV_REGISTER:
314                 if (vlan_proc_add_dev(dev) < 0)
315                         pr_warn("failed to add proc entry for %s\n", dev->name);
316                 break;
317         case NETDEV_UNREGISTER:
318                 vlan_proc_rem_dev(dev);
319                 break;
320         }
321 }
322
323 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
324                              void *ptr)
325 {
326         struct net_device *dev = ptr;
327         struct vlan_group *grp;
328         struct vlan_info *vlan_info;
329         int i, flgs;
330         struct net_device *vlandev;
331         struct vlan_dev_priv *vlan;
332         LIST_HEAD(list);
333
334         if (is_vlan_dev(dev))
335                 __vlan_device_event(dev, event);
336
337         if ((event == NETDEV_UP) &&
338             (dev->features & NETIF_F_HW_VLAN_FILTER)) {
339                 pr_info("adding VLAN 0 to HW filter on device %s\n",
340                         dev->name);
341                 vlan_vid_add(dev, 0);
342         }
343
344         vlan_info = rtnl_dereference(dev->vlan_info);
345         if (!vlan_info)
346                 goto out;
347         grp = &vlan_info->grp;
348
349         /* It is OK that we do not hold the group lock right now,
350          * as we run under the RTNL lock.
351          */
352
353         switch (event) {
354         case NETDEV_CHANGE:
355                 /* Propagate real device state to vlan devices */
356                 for (i = 0; i < VLAN_N_VID; i++) {
357                         vlandev = vlan_group_get_device(grp, i);
358                         if (!vlandev)
359                                 continue;
360
361                         netif_stacked_transfer_operstate(dev, vlandev);
362                 }
363                 break;
364
365         case NETDEV_CHANGEADDR:
366                 /* Adjust unicast filters on underlying device */
367                 for (i = 0; i < VLAN_N_VID; i++) {
368                         vlandev = vlan_group_get_device(grp, i);
369                         if (!vlandev)
370                                 continue;
371
372                         flgs = vlandev->flags;
373                         if (!(flgs & IFF_UP))
374                                 continue;
375
376                         vlan_sync_address(dev, vlandev);
377                 }
378                 break;
379
380         case NETDEV_CHANGEMTU:
381                 for (i = 0; i < VLAN_N_VID; i++) {
382                         vlandev = vlan_group_get_device(grp, i);
383                         if (!vlandev)
384                                 continue;
385
386                         if (vlandev->mtu <= dev->mtu)
387                                 continue;
388
389                         dev_set_mtu(vlandev, dev->mtu);
390                 }
391                 break;
392
393         case NETDEV_FEAT_CHANGE:
394                 /* Propagate device features to underlying device */
395                 for (i = 0; i < VLAN_N_VID; i++) {
396                         vlandev = vlan_group_get_device(grp, i);
397                         if (!vlandev)
398                                 continue;
399
400                         vlan_transfer_features(dev, vlandev);
401                 }
402
403                 break;
404
405         case NETDEV_DOWN:
406                 if (dev->features & NETIF_F_HW_VLAN_FILTER)
407                         vlan_vid_del(dev, 0);
408
409                 /* Put all VLANs for this dev in the down state too.  */
410                 for (i = 0; i < VLAN_N_VID; i++) {
411                         vlandev = vlan_group_get_device(grp, i);
412                         if (!vlandev)
413                                 continue;
414
415                         flgs = vlandev->flags;
416                         if (!(flgs & IFF_UP))
417                                 continue;
418
419                         vlan = vlan_dev_priv(vlandev);
420                         if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
421                                 dev_change_flags(vlandev, flgs & ~IFF_UP);
422                         netif_stacked_transfer_operstate(dev, vlandev);
423                 }
424                 break;
425
426         case NETDEV_UP:
427                 /* Put all VLANs for this dev in the up state too.  */
428                 for (i = 0; i < VLAN_N_VID; i++) {
429                         vlandev = vlan_group_get_device(grp, i);
430                         if (!vlandev)
431                                 continue;
432
433                         flgs = vlandev->flags;
434                         if (flgs & IFF_UP)
435                                 continue;
436
437                         vlan = vlan_dev_priv(vlandev);
438                         if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
439                                 dev_change_flags(vlandev, flgs | IFF_UP);
440                         netif_stacked_transfer_operstate(dev, vlandev);
441                 }
442                 break;
443
444         case NETDEV_UNREGISTER:
445                 /* twiddle thumbs on netns device moves */
446                 if (dev->reg_state != NETREG_UNREGISTERING)
447                         break;
448
449                 for (i = 0; i < VLAN_N_VID; i++) {
450                         vlandev = vlan_group_get_device(grp, i);
451                         if (!vlandev)
452                                 continue;
453
454                         /* removal of last vid destroys vlan_info, abort
455                          * afterwards */
456                         if (vlan_info->nr_vids == 1)
457                                 i = VLAN_N_VID;
458
459                         unregister_vlan_dev(vlandev, &list);
460                 }
461                 unregister_netdevice_many(&list);
462                 break;
463
464         case NETDEV_PRE_TYPE_CHANGE:
465                 /* Forbid underlaying device to change its type. */
466                 return NOTIFY_BAD;
467
468         case NETDEV_NOTIFY_PEERS:
469         case NETDEV_BONDING_FAILOVER:
470                 /* Propagate to vlan devices */
471                 for (i = 0; i < VLAN_N_VID; i++) {
472                         vlandev = vlan_group_get_device(grp, i);
473                         if (!vlandev)
474                                 continue;
475
476                         call_netdevice_notifiers(event, vlandev);
477                 }
478                 break;
479         }
480
481 out:
482         return NOTIFY_DONE;
483 }
484
485 static struct notifier_block vlan_notifier_block __read_mostly = {
486         .notifier_call = vlan_device_event,
487 };
488
489 /*
490  *      VLAN IOCTL handler.
491  *      o execute requested action or pass command to the device driver
492  *   arg is really a struct vlan_ioctl_args __user *.
493  */
494 static int vlan_ioctl_handler(struct net *net, void __user *arg)
495 {
496         int err;
497         struct vlan_ioctl_args args;
498         struct net_device *dev = NULL;
499
500         if (copy_from_user(&args, arg, sizeof(struct vlan_ioctl_args)))
501                 return -EFAULT;
502
503         /* Null terminate this sucker, just in case. */
504         args.device1[23] = 0;
505         args.u.device2[23] = 0;
506
507         rtnl_lock();
508
509         switch (args.cmd) {
510         case SET_VLAN_INGRESS_PRIORITY_CMD:
511         case SET_VLAN_EGRESS_PRIORITY_CMD:
512         case SET_VLAN_FLAG_CMD:
513         case ADD_VLAN_CMD:
514         case DEL_VLAN_CMD:
515         case GET_VLAN_REALDEV_NAME_CMD:
516         case GET_VLAN_VID_CMD:
517                 err = -ENODEV;
518                 dev = __dev_get_by_name(net, args.device1);
519                 if (!dev)
520                         goto out;
521
522                 err = -EINVAL;
523                 if (args.cmd != ADD_VLAN_CMD && !is_vlan_dev(dev))
524                         goto out;
525         }
526
527         switch (args.cmd) {
528         case SET_VLAN_INGRESS_PRIORITY_CMD:
529                 err = -EPERM;
530                 if (!capable(CAP_NET_ADMIN))
531                         break;
532                 vlan_dev_set_ingress_priority(dev,
533                                               args.u.skb_priority,
534                                               args.vlan_qos);
535                 err = 0;
536                 break;
537
538         case SET_VLAN_EGRESS_PRIORITY_CMD:
539                 err = -EPERM;
540                 if (!capable(CAP_NET_ADMIN))
541                         break;
542                 err = vlan_dev_set_egress_priority(dev,
543                                                    args.u.skb_priority,
544                                                    args.vlan_qos);
545                 break;
546
547         case SET_VLAN_FLAG_CMD:
548                 err = -EPERM;
549                 if (!capable(CAP_NET_ADMIN))
550                         break;
551                 err = vlan_dev_change_flags(dev,
552                                             args.vlan_qos ? args.u.flag : 0,
553                                             args.u.flag);
554                 break;
555
556         case SET_VLAN_NAME_TYPE_CMD:
557                 err = -EPERM;
558                 if (!capable(CAP_NET_ADMIN))
559                         break;
560                 if ((args.u.name_type >= 0) &&
561                     (args.u.name_type < VLAN_NAME_TYPE_HIGHEST)) {
562                         struct vlan_net *vn;
563
564                         vn = net_generic(net, vlan_net_id);
565                         vn->name_type = args.u.name_type;
566                         err = 0;
567                 } else {
568                         err = -EINVAL;
569                 }
570                 break;
571
572         case ADD_VLAN_CMD:
573                 err = -EPERM;
574                 if (!capable(CAP_NET_ADMIN))
575                         break;
576                 err = register_vlan_device(dev, args.u.VID);
577                 break;
578
579         case DEL_VLAN_CMD:
580                 err = -EPERM;
581                 if (!capable(CAP_NET_ADMIN))
582                         break;
583                 unregister_vlan_dev(dev, NULL);
584                 err = 0;
585                 break;
586
587         case GET_VLAN_REALDEV_NAME_CMD:
588                 err = 0;
589                 vlan_dev_get_realdev_name(dev, args.u.device2);
590                 if (copy_to_user(arg, &args,
591                                  sizeof(struct vlan_ioctl_args)))
592                         err = -EFAULT;
593                 break;
594
595         case GET_VLAN_VID_CMD:
596                 err = 0;
597                 args.u.VID = vlan_dev_vlan_id(dev);
598                 if (copy_to_user(arg, &args,
599                                  sizeof(struct vlan_ioctl_args)))
600                       err = -EFAULT;
601                 break;
602
603         default:
604                 err = -EOPNOTSUPP;
605                 break;
606         }
607 out:
608         rtnl_unlock();
609         return err;
610 }
611
612 static int __net_init vlan_init_net(struct net *net)
613 {
614         struct vlan_net *vn = net_generic(net, vlan_net_id);
615         int err;
616
617         vn->name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD;
618
619         err = vlan_proc_init(net);
620
621         return err;
622 }
623
624 static void __net_exit vlan_exit_net(struct net *net)
625 {
626         vlan_proc_cleanup(net);
627 }
628
629 static struct pernet_operations vlan_net_ops = {
630         .init = vlan_init_net,
631         .exit = vlan_exit_net,
632         .id   = &vlan_net_id,
633         .size = sizeof(struct vlan_net),
634 };
635
636 static int __init vlan_proto_init(void)
637 {
638         int err;
639
640         pr_info("%s v%s\n", vlan_fullname, vlan_version);
641
642         err = register_pernet_subsys(&vlan_net_ops);
643         if (err < 0)
644                 goto err0;
645
646         err = register_netdevice_notifier(&vlan_notifier_block);
647         if (err < 0)
648                 goto err2;
649
650         err = vlan_gvrp_init();
651         if (err < 0)
652                 goto err3;
653
654         err = vlan_netlink_init();
655         if (err < 0)
656                 goto err4;
657
658         vlan_ioctl_set(vlan_ioctl_handler);
659         return 0;
660
661 err4:
662         vlan_gvrp_uninit();
663 err3:
664         unregister_netdevice_notifier(&vlan_notifier_block);
665 err2:
666         unregister_pernet_subsys(&vlan_net_ops);
667 err0:
668         return err;
669 }
670
671 static void __exit vlan_cleanup_module(void)
672 {
673         vlan_ioctl_set(NULL);
674         vlan_netlink_fini();
675
676         unregister_netdevice_notifier(&vlan_notifier_block);
677
678         unregister_pernet_subsys(&vlan_net_ops);
679         rcu_barrier(); /* Wait for completion of call_rcu()'s */
680
681         vlan_gvrp_uninit();
682 }
683
684 module_init(vlan_proto_init);
685 module_exit(vlan_cleanup_module);
686
687 MODULE_LICENSE("GPL");
688 MODULE_VERSION(DRV_VERSION);