mac80211: Cancel the power save timer in ieee80211_stop.
[linux-2.6] / net / mac80211 / iface.c
1 /*
2  * Interface handling (except master interface)
3  *
4  * Copyright 2002-2005, Instant802 Networks, Inc.
5  * Copyright 2005-2006, Devicescape Software, Inc.
6  * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
7  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/kernel.h>
14 #include <linux/if_arp.h>
15 #include <linux/netdevice.h>
16 #include <linux/rtnetlink.h>
17 #include <net/mac80211.h>
18 #include "ieee80211_i.h"
19 #include "sta_info.h"
20 #include "debugfs_netdev.h"
21 #include "mesh.h"
22 #include "led.h"
23
24 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
25 {
26         int meshhdrlen;
27         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
28
29         meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
30
31         /* FIX: what would be proper limits for MTU?
32          * This interface uses 802.3 frames. */
33         if (new_mtu < 256 ||
34             new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
35                 return -EINVAL;
36         }
37
38 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
39         printk(KERN_DEBUG "%s: setting MTU %d\n", dev->name, new_mtu);
40 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
41         dev->mtu = new_mtu;
42         return 0;
43 }
44
45 static inline int identical_mac_addr_allowed(int type1, int type2)
46 {
47         return type1 == NL80211_IFTYPE_MONITOR ||
48                 type2 == NL80211_IFTYPE_MONITOR ||
49                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
50                 (type1 == NL80211_IFTYPE_WDS &&
51                         (type2 == NL80211_IFTYPE_WDS ||
52                          type2 == NL80211_IFTYPE_AP)) ||
53                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
54                 (type1 == NL80211_IFTYPE_AP_VLAN &&
55                         (type2 == NL80211_IFTYPE_AP ||
56                          type2 == NL80211_IFTYPE_AP_VLAN));
57 }
58
59 static int ieee80211_open(struct net_device *dev)
60 {
61         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
62         struct ieee80211_sub_if_data *nsdata;
63         struct ieee80211_local *local = sdata->local;
64         struct sta_info *sta;
65         struct ieee80211_if_init_conf conf;
66         u32 changed = 0;
67         int res;
68         u32 hw_reconf_flags = 0;
69         u8 null_addr[ETH_ALEN] = {0};
70
71         /* fail early if user set an invalid address */
72         if (compare_ether_addr(dev->dev_addr, null_addr) &&
73             !is_valid_ether_addr(dev->dev_addr))
74                 return -EADDRNOTAVAIL;
75
76         /* we hold the RTNL here so can safely walk the list */
77         list_for_each_entry(nsdata, &local->interfaces, list) {
78                 struct net_device *ndev = nsdata->dev;
79
80                 if (ndev != dev && netif_running(ndev)) {
81                         /*
82                          * Allow only a single IBSS interface to be up at any
83                          * time. This is restricted because beacon distribution
84                          * cannot work properly if both are in the same IBSS.
85                          *
86                          * To remove this restriction we'd have to disallow them
87                          * from setting the same SSID on different IBSS interfaces
88                          * belonging to the same hardware. Then, however, we're
89                          * faced with having to adopt two different TSF timers...
90                          */
91                         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
92                             nsdata->vif.type == NL80211_IFTYPE_ADHOC)
93                                 return -EBUSY;
94
95                         /*
96                          * The remaining checks are only performed for interfaces
97                          * with the same MAC address.
98                          */
99                         if (compare_ether_addr(dev->dev_addr, ndev->dev_addr))
100                                 continue;
101
102                         /*
103                          * check whether it may have the same address
104                          */
105                         if (!identical_mac_addr_allowed(sdata->vif.type,
106                                                         nsdata->vif.type))
107                                 return -ENOTUNIQ;
108
109                         /*
110                          * can only add VLANs to enabled APs
111                          */
112                         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
113                             nsdata->vif.type == NL80211_IFTYPE_AP)
114                                 sdata->bss = &nsdata->u.ap;
115                 }
116         }
117
118         switch (sdata->vif.type) {
119         case NL80211_IFTYPE_WDS:
120                 if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
121                         return -ENOLINK;
122                 break;
123         case NL80211_IFTYPE_AP_VLAN:
124                 if (!sdata->bss)
125                         return -ENOLINK;
126                 list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
127                 break;
128         case NL80211_IFTYPE_AP:
129                 sdata->bss = &sdata->u.ap;
130                 break;
131         case NL80211_IFTYPE_MESH_POINT:
132                 if (!ieee80211_vif_is_mesh(&sdata->vif))
133                         break;
134                 /* mesh ifaces must set allmulti to forward mcast traffic */
135                 atomic_inc(&local->iff_allmultis);
136                 break;
137         case NL80211_IFTYPE_STATION:
138         case NL80211_IFTYPE_MONITOR:
139         case NL80211_IFTYPE_ADHOC:
140                 /* no special treatment */
141                 break;
142         case NL80211_IFTYPE_UNSPECIFIED:
143         case __NL80211_IFTYPE_AFTER_LAST:
144                 /* cannot happen */
145                 WARN_ON(1);
146                 break;
147         }
148
149         if (local->open_count == 0) {
150                 res = 0;
151                 if (local->ops->start)
152                         res = local->ops->start(local_to_hw(local));
153                 if (res)
154                         goto err_del_bss;
155                 /* we're brought up, everything changes */
156                 hw_reconf_flags = ~0;
157                 ieee80211_led_radio(local, local->hw.conf.radio_enabled);
158         }
159
160         /*
161          * Check all interfaces and copy the hopefully now-present
162          * MAC address to those that have the special null one.
163          */
164         list_for_each_entry(nsdata, &local->interfaces, list) {
165                 struct net_device *ndev = nsdata->dev;
166
167                 /*
168                  * No need to check netif_running since we do not allow
169                  * it to start up with this invalid address.
170                  */
171                 if (compare_ether_addr(null_addr, ndev->dev_addr) == 0)
172                         memcpy(ndev->dev_addr,
173                                local->hw.wiphy->perm_addr,
174                                ETH_ALEN);
175         }
176
177         if (compare_ether_addr(null_addr, local->mdev->dev_addr) == 0)
178                 memcpy(local->mdev->dev_addr, local->hw.wiphy->perm_addr,
179                        ETH_ALEN);
180
181         /*
182          * Validate the MAC address for this device.
183          */
184         if (!is_valid_ether_addr(dev->dev_addr)) {
185                 if (!local->open_count && local->ops->stop)
186                         local->ops->stop(local_to_hw(local));
187                 return -EADDRNOTAVAIL;
188         }
189
190         switch (sdata->vif.type) {
191         case NL80211_IFTYPE_AP_VLAN:
192                 /* no need to tell driver */
193                 break;
194         case NL80211_IFTYPE_MONITOR:
195                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
196                         local->cooked_mntrs++;
197                         break;
198                 }
199
200                 /* must be before the call to ieee80211_configure_filter */
201                 local->monitors++;
202                 if (local->monitors == 1) {
203                         local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;
204                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
205                 }
206
207                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
208                         local->fif_fcsfail++;
209                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
210                         local->fif_plcpfail++;
211                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
212                         local->fif_control++;
213                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
214                         local->fif_other_bss++;
215
216                 netif_addr_lock_bh(local->mdev);
217                 ieee80211_configure_filter(local);
218                 netif_addr_unlock_bh(local->mdev);
219                 break;
220         case NL80211_IFTYPE_STATION:
221         case NL80211_IFTYPE_ADHOC:
222                 sdata->u.sta.flags &= ~IEEE80211_STA_PREV_BSSID_SET;
223                 /* fall through */
224         default:
225                 conf.vif = &sdata->vif;
226                 conf.type = sdata->vif.type;
227                 conf.mac_addr = dev->dev_addr;
228                 res = local->ops->add_interface(local_to_hw(local), &conf);
229                 if (res)
230                         goto err_stop;
231
232                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
233                         local->fif_other_bss++;
234                         netif_addr_lock_bh(local->mdev);
235                         ieee80211_configure_filter(local);
236                         netif_addr_unlock_bh(local->mdev);
237
238                         ieee80211_start_mesh(sdata);
239                 }
240                 changed |= ieee80211_reset_erp_info(sdata);
241                 ieee80211_bss_info_change_notify(sdata, changed);
242                 ieee80211_enable_keys(sdata);
243
244                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
245                     !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
246                         netif_carrier_off(dev);
247                 else
248                         netif_carrier_on(dev);
249         }
250
251         if (sdata->vif.type == NL80211_IFTYPE_WDS) {
252                 /* Create STA entry for the WDS peer */
253                 sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
254                                      GFP_KERNEL);
255                 if (!sta) {
256                         res = -ENOMEM;
257                         goto err_del_interface;
258                 }
259
260                 /* no locking required since STA is not live yet */
261                 sta->flags |= WLAN_STA_AUTHORIZED;
262
263                 res = sta_info_insert(sta);
264                 if (res) {
265                         /* STA has been freed */
266                         goto err_del_interface;
267                 }
268         }
269
270         if (local->open_count == 0) {
271                 res = dev_open(local->mdev);
272                 WARN_ON(res);
273                 if (res)
274                         goto err_del_interface;
275                 tasklet_enable(&local->tx_pending_tasklet);
276                 tasklet_enable(&local->tasklet);
277         }
278
279         /*
280          * set_multicast_list will be invoked by the networking core
281          * which will check whether any increments here were done in
282          * error and sync them down to the hardware as filter flags.
283          */
284         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
285                 atomic_inc(&local->iff_allmultis);
286
287         if (sdata->flags & IEEE80211_SDATA_PROMISC)
288                 atomic_inc(&local->iff_promiscs);
289
290         local->open_count++;
291         if (hw_reconf_flags) {
292                 ieee80211_hw_config(local, hw_reconf_flags);
293                 /*
294                  * set default queue parameters so drivers don't
295                  * need to initialise the hardware if the hardware
296                  * doesn't start up with sane defaults
297                  */
298                 ieee80211_set_wmm_default(sdata);
299         }
300
301         /*
302          * ieee80211_sta_work is disabled while network interface
303          * is down. Therefore, some configuration changes may not
304          * yet be effective. Trigger execution of ieee80211_sta_work
305          * to fix this.
306          */
307         if (sdata->vif.type == NL80211_IFTYPE_STATION ||
308             sdata->vif.type == NL80211_IFTYPE_ADHOC) {
309                 struct ieee80211_if_sta *ifsta = &sdata->u.sta;
310                 queue_work(local->hw.workqueue, &ifsta->work);
311         }
312
313         netif_tx_start_all_queues(dev);
314
315         return 0;
316  err_del_interface:
317         local->ops->remove_interface(local_to_hw(local), &conf);
318  err_stop:
319         if (!local->open_count && local->ops->stop)
320                 local->ops->stop(local_to_hw(local));
321  err_del_bss:
322         sdata->bss = NULL;
323         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
324                 list_del(&sdata->u.vlan.list);
325         return res;
326 }
327
328 static int ieee80211_stop(struct net_device *dev)
329 {
330         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
331         struct ieee80211_local *local = sdata->local;
332         struct ieee80211_if_init_conf conf;
333         struct sta_info *sta;
334         u32 hw_reconf_flags = 0;
335
336         /*
337          * Stop TX on this interface first.
338          */
339         netif_tx_stop_all_queues(dev);
340
341         /*
342          * Now delete all active aggregation sessions.
343          */
344         rcu_read_lock();
345
346         list_for_each_entry_rcu(sta, &local->sta_list, list) {
347                 if (sta->sdata == sdata)
348                         ieee80211_sta_tear_down_BA_sessions(sdata,
349                                                             sta->sta.addr);
350         }
351
352         rcu_read_unlock();
353
354         /*
355          * Remove all stations associated with this interface.
356          *
357          * This must be done before calling ops->remove_interface()
358          * because otherwise we can later invoke ops->sta_notify()
359          * whenever the STAs are removed, and that invalidates driver
360          * assumptions about always getting a vif pointer that is valid
361          * (because if we remove a STA after ops->remove_interface()
362          * the driver will have removed the vif info already!)
363          *
364          * We could relax this and only unlink the stations from the
365          * hash table and list but keep them on a per-sdata list that
366          * will be inserted back again when the interface is brought
367          * up again, but I don't currently see a use case for that,
368          * except with WDS which gets a STA entry created when it is
369          * brought up.
370          */
371         sta_info_flush(local, sdata);
372
373         /*
374          * Don't count this interface for promisc/allmulti while it
375          * is down. dev_mc_unsync() will invoke set_multicast_list
376          * on the master interface which will sync these down to the
377          * hardware as filter flags.
378          */
379         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
380                 atomic_dec(&local->iff_allmultis);
381
382         if (sdata->flags & IEEE80211_SDATA_PROMISC)
383                 atomic_dec(&local->iff_promiscs);
384
385         dev_mc_unsync(local->mdev, dev);
386         del_timer_sync(&local->dynamic_ps_timer);
387         cancel_work_sync(&local->dynamic_ps_enable_work);
388
389         /* APs need special treatment */
390         if (sdata->vif.type == NL80211_IFTYPE_AP) {
391                 struct ieee80211_sub_if_data *vlan, *tmp;
392                 struct beacon_data *old_beacon = sdata->u.ap.beacon;
393
394                 /* remove beacon */
395                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
396                 synchronize_rcu();
397                 kfree(old_beacon);
398
399                 /* down all dependent devices, that is VLANs */
400                 list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
401                                          u.vlan.list)
402                         dev_close(vlan->dev);
403                 WARN_ON(!list_empty(&sdata->u.ap.vlans));
404         }
405
406         local->open_count--;
407
408         switch (sdata->vif.type) {
409         case NL80211_IFTYPE_AP_VLAN:
410                 list_del(&sdata->u.vlan.list);
411                 /* no need to tell driver */
412                 break;
413         case NL80211_IFTYPE_MONITOR:
414                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
415                         local->cooked_mntrs--;
416                         break;
417                 }
418
419                 local->monitors--;
420                 if (local->monitors == 0) {
421                         local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
422                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
423                 }
424
425                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
426                         local->fif_fcsfail--;
427                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
428                         local->fif_plcpfail--;
429                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
430                         local->fif_control--;
431                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
432                         local->fif_other_bss--;
433
434                 netif_addr_lock_bh(local->mdev);
435                 ieee80211_configure_filter(local);
436                 netif_addr_unlock_bh(local->mdev);
437                 break;
438         case NL80211_IFTYPE_STATION:
439         case NL80211_IFTYPE_ADHOC:
440                 /* Announce that we are leaving the network. */
441                 if (sdata->u.sta.state != IEEE80211_STA_MLME_DISABLED)
442                         ieee80211_sta_deauthenticate(sdata,
443                                                 WLAN_REASON_DEAUTH_LEAVING);
444
445                 memset(sdata->u.sta.bssid, 0, ETH_ALEN);
446                 del_timer_sync(&sdata->u.sta.timer);
447                 /*
448                  * If the timer fired while we waited for it, it will have
449                  * requeued the work. Now the work will be running again
450                  * but will not rearm the timer again because it checks
451                  * whether the interface is running, which, at this point,
452                  * it no longer is.
453                  */
454                 cancel_work_sync(&sdata->u.sta.work);
455                 /*
456                  * When we get here, the interface is marked down.
457                  * Call synchronize_rcu() to wait for the RX path
458                  * should it be using the interface and enqueuing
459                  * frames at this very time on another CPU.
460                  */
461                 synchronize_rcu();
462                 skb_queue_purge(&sdata->u.sta.skb_queue);
463
464                 sdata->u.sta.flags &= ~(IEEE80211_STA_PRIVACY_INVOKED |
465                                         IEEE80211_STA_TKIP_WEP_USED);
466                 kfree(sdata->u.sta.extra_ie);
467                 sdata->u.sta.extra_ie = NULL;
468                 sdata->u.sta.extra_ie_len = 0;
469                 /* fall through */
470         case NL80211_IFTYPE_MESH_POINT:
471                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
472                         /* other_bss and allmulti are always set on mesh
473                          * ifaces */
474                         local->fif_other_bss--;
475                         atomic_dec(&local->iff_allmultis);
476
477                         netif_addr_lock_bh(local->mdev);
478                         ieee80211_configure_filter(local);
479                         netif_addr_unlock_bh(local->mdev);
480
481                         ieee80211_stop_mesh(sdata);
482                 }
483                 /* fall through */
484         default:
485                 if (local->scan_sdata == sdata) {
486                         if (!local->ops->hw_scan)
487                                 cancel_delayed_work_sync(&local->scan_work);
488                         /*
489                          * The software scan can no longer run now, so we can
490                          * clear out the scan_sdata reference. However, the
491                          * hardware scan may still be running. The complete
492                          * function must be prepared to handle a NULL value.
493                          */
494                         local->scan_sdata = NULL;
495                         /*
496                          * The memory barrier guarantees that another CPU
497                          * that is hardware-scanning will now see the fact
498                          * that this interface is gone.
499                          */
500                         smp_mb();
501                         /*
502                          * If software scanning, complete the scan but since
503                          * the scan_sdata is NULL already don't send out a
504                          * scan event to userspace -- the scan is incomplete.
505                          */
506                         if (local->sw_scanning)
507                                 ieee80211_scan_completed(&local->hw);
508                 }
509
510                 conf.vif = &sdata->vif;
511                 conf.type = sdata->vif.type;
512                 conf.mac_addr = dev->dev_addr;
513                 /* disable all keys for as long as this netdev is down */
514                 ieee80211_disable_keys(sdata);
515                 local->ops->remove_interface(local_to_hw(local), &conf);
516         }
517
518         sdata->bss = NULL;
519
520         if (local->open_count == 0) {
521                 if (netif_running(local->mdev))
522                         dev_close(local->mdev);
523
524                 if (local->ops->stop)
525                         local->ops->stop(local_to_hw(local));
526
527                 ieee80211_led_radio(local, 0);
528
529                 flush_workqueue(local->hw.workqueue);
530
531                 tasklet_disable(&local->tx_pending_tasklet);
532                 tasklet_disable(&local->tasklet);
533
534                 /* no reconfiguring after stop! */
535                 hw_reconf_flags = 0;
536         }
537
538         /* do after stop to avoid reconfiguring when we stop anyway */
539         if (hw_reconf_flags)
540                 ieee80211_hw_config(local, hw_reconf_flags);
541
542         return 0;
543 }
544
545 static void ieee80211_set_multicast_list(struct net_device *dev)
546 {
547         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
548         struct ieee80211_local *local = sdata->local;
549         int allmulti, promisc, sdata_allmulti, sdata_promisc;
550
551         allmulti = !!(dev->flags & IFF_ALLMULTI);
552         promisc = !!(dev->flags & IFF_PROMISC);
553         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
554         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
555
556         if (allmulti != sdata_allmulti) {
557                 if (dev->flags & IFF_ALLMULTI)
558                         atomic_inc(&local->iff_allmultis);
559                 else
560                         atomic_dec(&local->iff_allmultis);
561                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
562         }
563
564         if (promisc != sdata_promisc) {
565                 if (dev->flags & IFF_PROMISC)
566                         atomic_inc(&local->iff_promiscs);
567                 else
568                         atomic_dec(&local->iff_promiscs);
569                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
570         }
571
572         dev_mc_sync(local->mdev, dev);
573 }
574
575 static void ieee80211_if_setup(struct net_device *dev)
576 {
577         ether_setup(dev);
578         dev->hard_start_xmit = ieee80211_subif_start_xmit;
579         dev->wireless_handlers = &ieee80211_iw_handler_def;
580         dev->set_multicast_list = ieee80211_set_multicast_list;
581         dev->change_mtu = ieee80211_change_mtu;
582         dev->open = ieee80211_open;
583         dev->stop = ieee80211_stop;
584         dev->destructor = free_netdev;
585         /* we will validate the address ourselves in ->open */
586         dev->validate_addr = NULL;
587 }
588 /*
589  * Called when the netdev is removed or, by the code below, before
590  * the interface type changes.
591  */
592 static void ieee80211_teardown_sdata(struct net_device *dev)
593 {
594         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
595         struct ieee80211_local *local = sdata->local;
596         struct beacon_data *beacon;
597         struct sk_buff *skb;
598         int flushed;
599         int i;
600
601         /* free extra data */
602         ieee80211_free_keys(sdata);
603
604         ieee80211_debugfs_remove_netdev(sdata);
605
606         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
607                 __skb_queue_purge(&sdata->fragments[i].skb_list);
608         sdata->fragment_next = 0;
609
610         switch (sdata->vif.type) {
611         case NL80211_IFTYPE_AP:
612                 beacon = sdata->u.ap.beacon;
613                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
614                 synchronize_rcu();
615                 kfree(beacon);
616
617                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
618                         local->total_ps_buffered--;
619                         dev_kfree_skb(skb);
620                 }
621
622                 break;
623         case NL80211_IFTYPE_MESH_POINT:
624                 if (ieee80211_vif_is_mesh(&sdata->vif))
625                         mesh_rmc_free(sdata);
626                 break;
627         case NL80211_IFTYPE_STATION:
628         case NL80211_IFTYPE_ADHOC:
629                 kfree(sdata->u.sta.extra_ie);
630                 kfree(sdata->u.sta.assocreq_ies);
631                 kfree(sdata->u.sta.assocresp_ies);
632                 kfree_skb(sdata->u.sta.probe_resp);
633                 break;
634         case NL80211_IFTYPE_WDS:
635         case NL80211_IFTYPE_AP_VLAN:
636         case NL80211_IFTYPE_MONITOR:
637                 break;
638         case NL80211_IFTYPE_UNSPECIFIED:
639         case __NL80211_IFTYPE_AFTER_LAST:
640                 BUG();
641                 break;
642         }
643
644         flushed = sta_info_flush(local, sdata);
645         WARN_ON(flushed);
646 }
647
648 /*
649  * Helper function to initialise an interface to a specific type.
650  */
651 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
652                                   enum nl80211_iftype type)
653 {
654         /* clear type-dependent union */
655         memset(&sdata->u, 0, sizeof(sdata->u));
656
657         /* and set some type-dependent values */
658         sdata->vif.type = type;
659         sdata->dev->hard_start_xmit = ieee80211_subif_start_xmit;
660         sdata->wdev.iftype = type;
661
662         /* only monitor differs */
663         sdata->dev->type = ARPHRD_ETHER;
664
665         switch (type) {
666         case NL80211_IFTYPE_AP:
667                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
668                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
669                 break;
670         case NL80211_IFTYPE_STATION:
671         case NL80211_IFTYPE_ADHOC:
672                 ieee80211_sta_setup_sdata(sdata);
673                 break;
674         case NL80211_IFTYPE_MESH_POINT:
675                 if (ieee80211_vif_is_mesh(&sdata->vif))
676                         ieee80211_mesh_init_sdata(sdata);
677                 break;
678         case NL80211_IFTYPE_MONITOR:
679                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
680                 sdata->dev->hard_start_xmit = ieee80211_monitor_start_xmit;
681                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
682                                       MONITOR_FLAG_OTHER_BSS;
683                 break;
684         case NL80211_IFTYPE_WDS:
685         case NL80211_IFTYPE_AP_VLAN:
686                 break;
687         case NL80211_IFTYPE_UNSPECIFIED:
688         case __NL80211_IFTYPE_AFTER_LAST:
689                 BUG();
690                 break;
691         }
692
693         ieee80211_debugfs_add_netdev(sdata);
694 }
695
696 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
697                              enum nl80211_iftype type)
698 {
699         ASSERT_RTNL();
700
701         if (type == sdata->vif.type)
702                 return 0;
703
704         /* Setting ad-hoc mode on non-IBSS channel is not supported. */
705         if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
706             type == NL80211_IFTYPE_ADHOC)
707                 return -EOPNOTSUPP;
708
709         /*
710          * We could, here, on changes between IBSS/STA/MESH modes,
711          * invoke an MLME function instead that disassociates etc.
712          * and goes into the requested mode.
713          */
714
715         if (netif_running(sdata->dev))
716                 return -EBUSY;
717
718         /* Purge and reset type-dependent state. */
719         ieee80211_teardown_sdata(sdata->dev);
720         ieee80211_setup_sdata(sdata, type);
721
722         /* reset some values that shouldn't be kept across type changes */
723         sdata->vif.bss_conf.basic_rates =
724                 ieee80211_mandatory_rates(sdata->local,
725                         sdata->local->hw.conf.channel->band);
726         sdata->drop_unencrypted = 0;
727
728         return 0;
729 }
730
731 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
732                      struct net_device **new_dev, enum nl80211_iftype type,
733                      struct vif_params *params)
734 {
735         struct net_device *ndev;
736         struct ieee80211_sub_if_data *sdata = NULL;
737         int ret, i;
738
739         ASSERT_RTNL();
740
741         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
742                             name, ieee80211_if_setup);
743         if (!ndev)
744                 return -ENOMEM;
745
746         ndev->needed_headroom = local->tx_headroom +
747                                 4*6 /* four MAC addresses */
748                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
749                                 + 6 /* mesh */
750                                 + 8 /* rfc1042/bridge tunnel */
751                                 - ETH_HLEN /* ethernet hard_header_len */
752                                 + IEEE80211_ENCRYPT_HEADROOM;
753         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
754
755         ret = dev_alloc_name(ndev, ndev->name);
756         if (ret < 0)
757                 goto fail;
758
759         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
760         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
761
762         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
763         sdata = netdev_priv(ndev);
764         ndev->ieee80211_ptr = &sdata->wdev;
765
766         /* initialise type-independent data */
767         sdata->wdev.wiphy = local->hw.wiphy;
768         sdata->local = local;
769         sdata->dev = ndev;
770
771         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
772                 skb_queue_head_init(&sdata->fragments[i].skb_list);
773
774         INIT_LIST_HEAD(&sdata->key_list);
775
776         sdata->force_unicast_rateidx = -1;
777         sdata->max_ratectrl_rateidx = -1;
778
779         /* setup type-dependent data */
780         ieee80211_setup_sdata(sdata, type);
781
782         ret = register_netdevice(ndev);
783         if (ret)
784                 goto fail;
785
786         ndev->uninit = ieee80211_teardown_sdata;
787
788         if (ieee80211_vif_is_mesh(&sdata->vif) &&
789             params && params->mesh_id_len)
790                 ieee80211_sdata_set_mesh_id(sdata,
791                                             params->mesh_id_len,
792                                             params->mesh_id);
793
794         list_add_tail_rcu(&sdata->list, &local->interfaces);
795
796         if (new_dev)
797                 *new_dev = ndev;
798
799         return 0;
800
801  fail:
802         free_netdev(ndev);
803         return ret;
804 }
805
806 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
807 {
808         ASSERT_RTNL();
809
810         list_del_rcu(&sdata->list);
811         synchronize_rcu();
812         unregister_netdevice(sdata->dev);
813 }
814
815 /*
816  * Remove all interfaces, may only be called at hardware unregistration
817  * time because it doesn't do RCU-safe list removals.
818  */
819 void ieee80211_remove_interfaces(struct ieee80211_local *local)
820 {
821         struct ieee80211_sub_if_data *sdata, *tmp;
822
823         ASSERT_RTNL();
824
825         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
826                 list_del(&sdata->list);
827                 unregister_netdevice(sdata->dev);
828         }
829 }