mac80211: don't try to do anything on unchanged genIE
[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 #include "driver-ops.h"
24
25 /**
26  * DOC: Interface list locking
27  *
28  * The interface list in each struct ieee80211_local is protected
29  * three-fold:
30  *
31  * (1) modifications may only be done under the RTNL
32  * (2) modifications and readers are protected against each other by
33  *     the iflist_mtx.
34  * (3) modifications are done in an RCU manner so atomic readers
35  *     can traverse the list in RCU-safe blocks.
36  *
37  * As a consequence, reads (traversals) of the list can be protected
38  * by either the RTNL, the iflist_mtx or RCU.
39  */
40
41
42 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
43 {
44         int meshhdrlen;
45         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
46
47         meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
48
49         /* FIX: what would be proper limits for MTU?
50          * This interface uses 802.3 frames. */
51         if (new_mtu < 256 ||
52             new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
53                 return -EINVAL;
54         }
55
56 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
57         printk(KERN_DEBUG "%s: setting MTU %d\n", dev->name, new_mtu);
58 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
59         dev->mtu = new_mtu;
60         return 0;
61 }
62
63 static inline int identical_mac_addr_allowed(int type1, int type2)
64 {
65         return type1 == NL80211_IFTYPE_MONITOR ||
66                 type2 == NL80211_IFTYPE_MONITOR ||
67                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
68                 (type1 == NL80211_IFTYPE_WDS &&
69                         (type2 == NL80211_IFTYPE_WDS ||
70                          type2 == NL80211_IFTYPE_AP)) ||
71                 (type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
72                 (type1 == NL80211_IFTYPE_AP_VLAN &&
73                         (type2 == NL80211_IFTYPE_AP ||
74                          type2 == NL80211_IFTYPE_AP_VLAN));
75 }
76
77 static int ieee80211_open(struct net_device *dev)
78 {
79         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
80         struct ieee80211_sub_if_data *nsdata;
81         struct ieee80211_local *local = sdata->local;
82         struct sta_info *sta;
83         struct ieee80211_if_init_conf conf;
84         u32 changed = 0;
85         int res;
86         u32 hw_reconf_flags = 0;
87         u8 null_addr[ETH_ALEN] = {0};
88
89         /* fail early if user set an invalid address */
90         if (compare_ether_addr(dev->dev_addr, null_addr) &&
91             !is_valid_ether_addr(dev->dev_addr))
92                 return -EADDRNOTAVAIL;
93
94         /* we hold the RTNL here so can safely walk the list */
95         list_for_each_entry(nsdata, &local->interfaces, list) {
96                 struct net_device *ndev = nsdata->dev;
97
98                 if (ndev != dev && netif_running(ndev)) {
99                         /*
100                          * Allow only a single IBSS interface to be up at any
101                          * time. This is restricted because beacon distribution
102                          * cannot work properly if both are in the same IBSS.
103                          *
104                          * To remove this restriction we'd have to disallow them
105                          * from setting the same SSID on different IBSS interfaces
106                          * belonging to the same hardware. Then, however, we're
107                          * faced with having to adopt two different TSF timers...
108                          */
109                         if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
110                             nsdata->vif.type == NL80211_IFTYPE_ADHOC)
111                                 return -EBUSY;
112
113                         /*
114                          * The remaining checks are only performed for interfaces
115                          * with the same MAC address.
116                          */
117                         if (compare_ether_addr(dev->dev_addr, ndev->dev_addr))
118                                 continue;
119
120                         /*
121                          * check whether it may have the same address
122                          */
123                         if (!identical_mac_addr_allowed(sdata->vif.type,
124                                                         nsdata->vif.type))
125                                 return -ENOTUNIQ;
126
127                         /*
128                          * can only add VLANs to enabled APs
129                          */
130                         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
131                             nsdata->vif.type == NL80211_IFTYPE_AP)
132                                 sdata->bss = &nsdata->u.ap;
133                 }
134         }
135
136         switch (sdata->vif.type) {
137         case NL80211_IFTYPE_WDS:
138                 if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
139                         return -ENOLINK;
140                 break;
141         case NL80211_IFTYPE_AP_VLAN:
142                 if (!sdata->bss)
143                         return -ENOLINK;
144                 list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
145                 break;
146         case NL80211_IFTYPE_AP:
147                 sdata->bss = &sdata->u.ap;
148                 break;
149         case NL80211_IFTYPE_MESH_POINT:
150                 if (!ieee80211_vif_is_mesh(&sdata->vif))
151                         break;
152                 /* mesh ifaces must set allmulti to forward mcast traffic */
153                 atomic_inc(&local->iff_allmultis);
154                 break;
155         case NL80211_IFTYPE_STATION:
156         case NL80211_IFTYPE_MONITOR:
157         case NL80211_IFTYPE_ADHOC:
158                 /* no special treatment */
159                 break;
160         case NL80211_IFTYPE_UNSPECIFIED:
161         case __NL80211_IFTYPE_AFTER_LAST:
162                 /* cannot happen */
163                 WARN_ON(1);
164                 break;
165         }
166
167         if (local->open_count == 0) {
168                 res = drv_start(local);
169                 if (res)
170                         goto err_del_bss;
171                 /* we're brought up, everything changes */
172                 hw_reconf_flags = ~0;
173                 ieee80211_led_radio(local, local->hw.conf.radio_enabled);
174         }
175
176         /*
177          * Check all interfaces and copy the hopefully now-present
178          * MAC address to those that have the special null one.
179          */
180         list_for_each_entry(nsdata, &local->interfaces, list) {
181                 struct net_device *ndev = nsdata->dev;
182
183                 /*
184                  * No need to check netif_running since we do not allow
185                  * it to start up with this invalid address.
186                  */
187                 if (compare_ether_addr(null_addr, ndev->dev_addr) == 0)
188                         memcpy(ndev->dev_addr,
189                                local->hw.wiphy->perm_addr,
190                                ETH_ALEN);
191         }
192
193         if (compare_ether_addr(null_addr, local->mdev->dev_addr) == 0)
194                 memcpy(local->mdev->dev_addr, local->hw.wiphy->perm_addr,
195                        ETH_ALEN);
196
197         /*
198          * Validate the MAC address for this device.
199          */
200         if (!is_valid_ether_addr(dev->dev_addr)) {
201                 if (!local->open_count)
202                         drv_stop(local);
203                 return -EADDRNOTAVAIL;
204         }
205
206         switch (sdata->vif.type) {
207         case NL80211_IFTYPE_AP_VLAN:
208                 /* no need to tell driver */
209                 break;
210         case NL80211_IFTYPE_MONITOR:
211                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
212                         local->cooked_mntrs++;
213                         break;
214                 }
215
216                 /* must be before the call to ieee80211_configure_filter */
217                 local->monitors++;
218                 if (local->monitors == 1) {
219                         local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;
220                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
221                 }
222
223                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
224                         local->fif_fcsfail++;
225                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
226                         local->fif_plcpfail++;
227                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
228                         local->fif_control++;
229                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
230                         local->fif_other_bss++;
231
232                 netif_addr_lock_bh(local->mdev);
233                 ieee80211_configure_filter(local);
234                 netif_addr_unlock_bh(local->mdev);
235                 break;
236         case NL80211_IFTYPE_STATION:
237                 sdata->u.mgd.flags &= ~IEEE80211_STA_PREV_BSSID_SET;
238                 /* fall through */
239         default:
240                 conf.vif = &sdata->vif;
241                 conf.type = sdata->vif.type;
242                 conf.mac_addr = dev->dev_addr;
243                 res = drv_add_interface(local, &conf);
244                 if (res)
245                         goto err_stop;
246
247                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
248                         local->fif_other_bss++;
249                         netif_addr_lock_bh(local->mdev);
250                         ieee80211_configure_filter(local);
251                         netif_addr_unlock_bh(local->mdev);
252
253                         ieee80211_start_mesh(sdata);
254                 }
255                 changed |= ieee80211_reset_erp_info(sdata);
256                 ieee80211_bss_info_change_notify(sdata, changed);
257                 ieee80211_enable_keys(sdata);
258
259                 if (sdata->vif.type == NL80211_IFTYPE_STATION)
260                         netif_carrier_off(dev);
261                 else
262                         netif_carrier_on(dev);
263         }
264
265         if (sdata->vif.type == NL80211_IFTYPE_WDS) {
266                 /* Create STA entry for the WDS peer */
267                 sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
268                                      GFP_KERNEL);
269                 if (!sta) {
270                         res = -ENOMEM;
271                         goto err_del_interface;
272                 }
273
274                 /* no locking required since STA is not live yet */
275                 sta->flags |= WLAN_STA_AUTHORIZED;
276
277                 res = sta_info_insert(sta);
278                 if (res) {
279                         /* STA has been freed */
280                         goto err_del_interface;
281                 }
282         }
283
284         if (local->open_count == 0) {
285                 res = dev_open(local->mdev);
286                 WARN_ON(res);
287                 if (res)
288                         goto err_del_interface;
289                 tasklet_enable(&local->tx_pending_tasklet);
290                 tasklet_enable(&local->tasklet);
291         }
292
293         /*
294          * set_multicast_list will be invoked by the networking core
295          * which will check whether any increments here were done in
296          * error and sync them down to the hardware as filter flags.
297          */
298         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
299                 atomic_inc(&local->iff_allmultis);
300
301         if (sdata->flags & IEEE80211_SDATA_PROMISC)
302                 atomic_inc(&local->iff_promiscs);
303
304         hw_reconf_flags |= __ieee80211_recalc_idle(local);
305
306         local->open_count++;
307         if (hw_reconf_flags) {
308                 ieee80211_hw_config(local, hw_reconf_flags);
309                 /*
310                  * set default queue parameters so drivers don't
311                  * need to initialise the hardware if the hardware
312                  * doesn't start up with sane defaults
313                  */
314                 ieee80211_set_wmm_default(sdata);
315         }
316
317         ieee80211_recalc_ps(local, -1);
318
319         /*
320          * ieee80211_sta_work is disabled while network interface
321          * is down. Therefore, some configuration changes may not
322          * yet be effective. Trigger execution of ieee80211_sta_work
323          * to fix this.
324          */
325         if (sdata->vif.type == NL80211_IFTYPE_STATION)
326                 queue_work(local->hw.workqueue, &sdata->u.mgd.work);
327
328         netif_tx_start_all_queues(dev);
329
330         return 0;
331  err_del_interface:
332         drv_remove_interface(local, &conf);
333  err_stop:
334         if (!local->open_count)
335                 drv_stop(local);
336  err_del_bss:
337         sdata->bss = NULL;
338         if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
339                 list_del(&sdata->u.vlan.list);
340         return res;
341 }
342
343 static int ieee80211_stop(struct net_device *dev)
344 {
345         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
346         struct ieee80211_local *local = sdata->local;
347         struct ieee80211_if_init_conf conf;
348         struct sta_info *sta;
349         u32 hw_reconf_flags = 0;
350
351         /*
352          * Stop TX on this interface first.
353          */
354         netif_tx_stop_all_queues(dev);
355
356         /*
357          * Now delete all active aggregation sessions.
358          */
359         rcu_read_lock();
360
361         list_for_each_entry_rcu(sta, &local->sta_list, list) {
362                 if (sta->sdata == sdata)
363                         ieee80211_sta_tear_down_BA_sessions(sta);
364         }
365
366         rcu_read_unlock();
367
368         /*
369          * Announce that we are leaving the network, in case we are a
370          * station interface type. This must be done before removing
371          * all stations associated with sta_info_flush, otherwise STA
372          * information will be gone and no announce being done.
373          */
374         if (sdata->vif.type == NL80211_IFTYPE_STATION) {
375                 if (sdata->u.mgd.state != IEEE80211_STA_MLME_DISABLED)
376                         ieee80211_sta_deauthenticate(sdata,
377                                 WLAN_REASON_DEAUTH_LEAVING);
378         }
379
380         /*
381          * Remove all stations associated with this interface.
382          *
383          * This must be done before calling ops->remove_interface()
384          * because otherwise we can later invoke ops->sta_notify()
385          * whenever the STAs are removed, and that invalidates driver
386          * assumptions about always getting a vif pointer that is valid
387          * (because if we remove a STA after ops->remove_interface()
388          * the driver will have removed the vif info already!)
389          *
390          * We could relax this and only unlink the stations from the
391          * hash table and list but keep them on a per-sdata list that
392          * will be inserted back again when the interface is brought
393          * up again, but I don't currently see a use case for that,
394          * except with WDS which gets a STA entry created when it is
395          * brought up.
396          */
397         sta_info_flush(local, sdata);
398
399         /*
400          * Don't count this interface for promisc/allmulti while it
401          * is down. dev_mc_unsync() will invoke set_multicast_list
402          * on the master interface which will sync these down to the
403          * hardware as filter flags.
404          */
405         if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
406                 atomic_dec(&local->iff_allmultis);
407
408         if (sdata->flags & IEEE80211_SDATA_PROMISC)
409                 atomic_dec(&local->iff_promiscs);
410
411         dev_mc_unsync(local->mdev, dev);
412         del_timer_sync(&local->dynamic_ps_timer);
413         cancel_work_sync(&local->dynamic_ps_enable_work);
414
415         /* APs need special treatment */
416         if (sdata->vif.type == NL80211_IFTYPE_AP) {
417                 struct ieee80211_sub_if_data *vlan, *tmp;
418                 struct beacon_data *old_beacon = sdata->u.ap.beacon;
419
420                 /* remove beacon */
421                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
422                 synchronize_rcu();
423                 kfree(old_beacon);
424
425                 /* down all dependent devices, that is VLANs */
426                 list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
427                                          u.vlan.list)
428                         dev_close(vlan->dev);
429                 WARN_ON(!list_empty(&sdata->u.ap.vlans));
430         }
431
432         local->open_count--;
433
434         switch (sdata->vif.type) {
435         case NL80211_IFTYPE_AP_VLAN:
436                 list_del(&sdata->u.vlan.list);
437                 /* no need to tell driver */
438                 break;
439         case NL80211_IFTYPE_MONITOR:
440                 if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
441                         local->cooked_mntrs--;
442                         break;
443                 }
444
445                 local->monitors--;
446                 if (local->monitors == 0) {
447                         local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;
448                         hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
449                 }
450
451                 if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
452                         local->fif_fcsfail--;
453                 if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
454                         local->fif_plcpfail--;
455                 if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
456                         local->fif_control--;
457                 if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
458                         local->fif_other_bss--;
459
460                 netif_addr_lock_bh(local->mdev);
461                 ieee80211_configure_filter(local);
462                 netif_addr_unlock_bh(local->mdev);
463                 break;
464         case NL80211_IFTYPE_STATION:
465                 memset(sdata->u.mgd.bssid, 0, ETH_ALEN);
466                 del_timer_sync(&sdata->u.mgd.chswitch_timer);
467                 del_timer_sync(&sdata->u.mgd.timer);
468                 /*
469                  * If the timer fired while we waited for it, it will have
470                  * requeued the work. Now the work will be running again
471                  * but will not rearm the timer again because it checks
472                  * whether the interface is running, which, at this point,
473                  * it no longer is.
474                  */
475                 cancel_work_sync(&sdata->u.mgd.work);
476                 cancel_work_sync(&sdata->u.mgd.chswitch_work);
477
478                 cancel_work_sync(&sdata->u.mgd.beacon_loss_work);
479
480                 /*
481                  * When we get here, the interface is marked down.
482                  * Call synchronize_rcu() to wait for the RX path
483                  * should it be using the interface and enqueuing
484                  * frames at this very time on another CPU.
485                  */
486                 synchronize_rcu();
487                 skb_queue_purge(&sdata->u.mgd.skb_queue);
488
489                 sdata->u.mgd.flags &= ~(IEEE80211_STA_PRIVACY_INVOKED |
490                                         IEEE80211_STA_TKIP_WEP_USED);
491                 kfree(sdata->u.mgd.extra_ie);
492                 sdata->u.mgd.extra_ie = NULL;
493                 sdata->u.mgd.extra_ie_len = 0;
494                 /* fall through */
495         case NL80211_IFTYPE_ADHOC:
496                 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
497                         del_timer_sync(&sdata->u.ibss.timer);
498                         cancel_work_sync(&sdata->u.ibss.work);
499                         synchronize_rcu();
500                         skb_queue_purge(&sdata->u.ibss.skb_queue);
501                 }
502                 /* fall through */
503         case NL80211_IFTYPE_MESH_POINT:
504                 if (ieee80211_vif_is_mesh(&sdata->vif)) {
505                         /* other_bss and allmulti are always set on mesh
506                          * ifaces */
507                         local->fif_other_bss--;
508                         atomic_dec(&local->iff_allmultis);
509
510                         netif_addr_lock_bh(local->mdev);
511                         ieee80211_configure_filter(local);
512                         netif_addr_unlock_bh(local->mdev);
513
514                         ieee80211_stop_mesh(sdata);
515                 }
516                 /* fall through */
517         default:
518                 if (local->scan_sdata == sdata) {
519                         if (!local->ops->hw_scan)
520                                 cancel_delayed_work_sync(&local->scan_work);
521                         /*
522                          * The software scan can no longer run now, so we can
523                          * clear out the scan_sdata reference. However, the
524                          * hardware scan may still be running. The complete
525                          * function must be prepared to handle a NULL value.
526                          */
527                         local->scan_sdata = NULL;
528                         /*
529                          * The memory barrier guarantees that another CPU
530                          * that is hardware-scanning will now see the fact
531                          * that this interface is gone.
532                          */
533                         smp_mb();
534                         /*
535                          * If software scanning, complete the scan but since
536                          * the scan_sdata is NULL already don't send out a
537                          * scan event to userspace -- the scan is incomplete.
538                          */
539                         if (local->sw_scanning)
540                                 ieee80211_scan_completed(&local->hw, true);
541                 }
542
543                 conf.vif = &sdata->vif;
544                 conf.type = sdata->vif.type;
545                 conf.mac_addr = dev->dev_addr;
546                 /* disable all keys for as long as this netdev is down */
547                 ieee80211_disable_keys(sdata);
548                 drv_remove_interface(local, &conf);
549         }
550
551         sdata->bss = NULL;
552
553         hw_reconf_flags |= __ieee80211_recalc_idle(local);
554
555         ieee80211_recalc_ps(local, -1);
556
557         if (local->open_count == 0) {
558                 if (netif_running(local->mdev))
559                         dev_close(local->mdev);
560
561                 drv_stop(local);
562
563                 ieee80211_led_radio(local, 0);
564
565                 flush_workqueue(local->hw.workqueue);
566
567                 tasklet_disable(&local->tx_pending_tasklet);
568                 tasklet_disable(&local->tasklet);
569
570                 /* no reconfiguring after stop! */
571                 hw_reconf_flags = 0;
572         }
573
574         /* do after stop to avoid reconfiguring when we stop anyway */
575         if (hw_reconf_flags)
576                 ieee80211_hw_config(local, hw_reconf_flags);
577
578         return 0;
579 }
580
581 static void ieee80211_set_multicast_list(struct net_device *dev)
582 {
583         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
584         struct ieee80211_local *local = sdata->local;
585         int allmulti, promisc, sdata_allmulti, sdata_promisc;
586
587         allmulti = !!(dev->flags & IFF_ALLMULTI);
588         promisc = !!(dev->flags & IFF_PROMISC);
589         sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
590         sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
591
592         if (allmulti != sdata_allmulti) {
593                 if (dev->flags & IFF_ALLMULTI)
594                         atomic_inc(&local->iff_allmultis);
595                 else
596                         atomic_dec(&local->iff_allmultis);
597                 sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
598         }
599
600         if (promisc != sdata_promisc) {
601                 if (dev->flags & IFF_PROMISC)
602                         atomic_inc(&local->iff_promiscs);
603                 else
604                         atomic_dec(&local->iff_promiscs);
605                 sdata->flags ^= IEEE80211_SDATA_PROMISC;
606         }
607
608         dev_mc_sync(local->mdev, dev);
609 }
610
611 /*
612  * Called when the netdev is removed or, by the code below, before
613  * the interface type changes.
614  */
615 static void ieee80211_teardown_sdata(struct net_device *dev)
616 {
617         struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
618         struct ieee80211_local *local = sdata->local;
619         struct beacon_data *beacon;
620         struct sk_buff *skb;
621         int flushed;
622         int i;
623
624         /* free extra data */
625         ieee80211_free_keys(sdata);
626
627         ieee80211_debugfs_remove_netdev(sdata);
628
629         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
630                 __skb_queue_purge(&sdata->fragments[i].skb_list);
631         sdata->fragment_next = 0;
632
633         switch (sdata->vif.type) {
634         case NL80211_IFTYPE_AP:
635                 beacon = sdata->u.ap.beacon;
636                 rcu_assign_pointer(sdata->u.ap.beacon, NULL);
637                 synchronize_rcu();
638                 kfree(beacon);
639
640                 while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
641                         local->total_ps_buffered--;
642                         dev_kfree_skb(skb);
643                 }
644
645                 break;
646         case NL80211_IFTYPE_MESH_POINT:
647                 if (ieee80211_vif_is_mesh(&sdata->vif))
648                         mesh_rmc_free(sdata);
649                 break;
650         case NL80211_IFTYPE_ADHOC:
651                 if (WARN_ON(sdata->u.ibss.presp))
652                         kfree_skb(sdata->u.ibss.presp);
653                 break;
654         case NL80211_IFTYPE_STATION:
655                 kfree(sdata->u.mgd.extra_ie);
656                 kfree(sdata->u.mgd.assocreq_ies);
657                 kfree(sdata->u.mgd.assocresp_ies);
658                 kfree(sdata->u.mgd.sme_auth_ie);
659                 break;
660         case NL80211_IFTYPE_WDS:
661         case NL80211_IFTYPE_AP_VLAN:
662         case NL80211_IFTYPE_MONITOR:
663                 break;
664         case NL80211_IFTYPE_UNSPECIFIED:
665         case __NL80211_IFTYPE_AFTER_LAST:
666                 BUG();
667                 break;
668         }
669
670         flushed = sta_info_flush(local, sdata);
671         WARN_ON(flushed);
672 }
673
674 static const struct net_device_ops ieee80211_dataif_ops = {
675         .ndo_open               = ieee80211_open,
676         .ndo_stop               = ieee80211_stop,
677         .ndo_uninit             = ieee80211_teardown_sdata,
678         .ndo_start_xmit         = ieee80211_subif_start_xmit,
679         .ndo_set_multicast_list = ieee80211_set_multicast_list,
680         .ndo_change_mtu         = ieee80211_change_mtu,
681         .ndo_set_mac_address    = eth_mac_addr,
682 };
683
684 static const struct net_device_ops ieee80211_monitorif_ops = {
685         .ndo_open               = ieee80211_open,
686         .ndo_stop               = ieee80211_stop,
687         .ndo_uninit             = ieee80211_teardown_sdata,
688         .ndo_start_xmit         = ieee80211_monitor_start_xmit,
689         .ndo_set_multicast_list = ieee80211_set_multicast_list,
690         .ndo_change_mtu         = ieee80211_change_mtu,
691         .ndo_set_mac_address    = eth_mac_addr,
692 };
693
694 static void ieee80211_if_setup(struct net_device *dev)
695 {
696         ether_setup(dev);
697         dev->netdev_ops = &ieee80211_dataif_ops;
698         dev->wireless_handlers = &ieee80211_iw_handler_def;
699         dev->destructor = free_netdev;
700 }
701
702 /*
703  * Helper function to initialise an interface to a specific type.
704  */
705 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
706                                   enum nl80211_iftype type)
707 {
708         /* clear type-dependent union */
709         memset(&sdata->u, 0, sizeof(sdata->u));
710
711         /* and set some type-dependent values */
712         sdata->vif.type = type;
713         sdata->dev->netdev_ops = &ieee80211_dataif_ops;
714         sdata->wdev.iftype = type;
715
716         /* only monitor differs */
717         sdata->dev->type = ARPHRD_ETHER;
718
719         switch (type) {
720         case NL80211_IFTYPE_AP:
721                 skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
722                 INIT_LIST_HEAD(&sdata->u.ap.vlans);
723                 break;
724         case NL80211_IFTYPE_STATION:
725                 ieee80211_sta_setup_sdata(sdata);
726                 break;
727         case NL80211_IFTYPE_ADHOC:
728                 ieee80211_ibss_setup_sdata(sdata);
729                 break;
730         case NL80211_IFTYPE_MESH_POINT:
731                 if (ieee80211_vif_is_mesh(&sdata->vif))
732                         ieee80211_mesh_init_sdata(sdata);
733                 break;
734         case NL80211_IFTYPE_MONITOR:
735                 sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
736                 sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
737                 sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
738                                       MONITOR_FLAG_OTHER_BSS;
739                 break;
740         case NL80211_IFTYPE_WDS:
741         case NL80211_IFTYPE_AP_VLAN:
742                 break;
743         case NL80211_IFTYPE_UNSPECIFIED:
744         case __NL80211_IFTYPE_AFTER_LAST:
745                 BUG();
746                 break;
747         }
748
749         ieee80211_debugfs_add_netdev(sdata);
750 }
751
752 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
753                              enum nl80211_iftype type)
754 {
755         ASSERT_RTNL();
756
757         if (type == sdata->vif.type)
758                 return 0;
759
760         /* Setting ad-hoc mode on non-IBSS channel is not supported. */
761         if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
762             type == NL80211_IFTYPE_ADHOC)
763                 return -EOPNOTSUPP;
764
765         /*
766          * We could, here, on changes between IBSS/STA/MESH modes,
767          * invoke an MLME function instead that disassociates etc.
768          * and goes into the requested mode.
769          */
770
771         if (netif_running(sdata->dev))
772                 return -EBUSY;
773
774         /* Purge and reset type-dependent state. */
775         ieee80211_teardown_sdata(sdata->dev);
776         ieee80211_setup_sdata(sdata, type);
777
778         /* reset some values that shouldn't be kept across type changes */
779         sdata->vif.bss_conf.basic_rates =
780                 ieee80211_mandatory_rates(sdata->local,
781                         sdata->local->hw.conf.channel->band);
782         sdata->drop_unencrypted = 0;
783
784         return 0;
785 }
786
787 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
788                      struct net_device **new_dev, enum nl80211_iftype type,
789                      struct vif_params *params)
790 {
791         struct net_device *ndev;
792         struct ieee80211_sub_if_data *sdata = NULL;
793         int ret, i;
794
795         ASSERT_RTNL();
796
797         ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,
798                             name, ieee80211_if_setup);
799         if (!ndev)
800                 return -ENOMEM;
801
802         ndev->needed_headroom = local->tx_headroom +
803                                 4*6 /* four MAC addresses */
804                                 + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
805                                 + 6 /* mesh */
806                                 + 8 /* rfc1042/bridge tunnel */
807                                 - ETH_HLEN /* ethernet hard_header_len */
808                                 + IEEE80211_ENCRYPT_HEADROOM;
809         ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
810
811         ret = dev_alloc_name(ndev, ndev->name);
812         if (ret < 0)
813                 goto fail;
814
815         memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
816         SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
817         ndev->features |= NETIF_F_NETNS_LOCAL;
818
819         /* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
820         sdata = netdev_priv(ndev);
821         ndev->ieee80211_ptr = &sdata->wdev;
822
823         /* initialise type-independent data */
824         sdata->wdev.wiphy = local->hw.wiphy;
825         sdata->local = local;
826         sdata->dev = ndev;
827
828         for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
829                 skb_queue_head_init(&sdata->fragments[i].skb_list);
830
831         INIT_LIST_HEAD(&sdata->key_list);
832
833         sdata->force_unicast_rateidx = -1;
834         sdata->max_ratectrl_rateidx = -1;
835
836         /* setup type-dependent data */
837         ieee80211_setup_sdata(sdata, type);
838
839         ret = register_netdevice(ndev);
840         if (ret)
841                 goto fail;
842
843         if (ieee80211_vif_is_mesh(&sdata->vif) &&
844             params && params->mesh_id_len)
845                 ieee80211_sdata_set_mesh_id(sdata,
846                                             params->mesh_id_len,
847                                             params->mesh_id);
848
849         mutex_lock(&local->iflist_mtx);
850         list_add_tail_rcu(&sdata->list, &local->interfaces);
851         mutex_unlock(&local->iflist_mtx);
852
853         if (new_dev)
854                 *new_dev = ndev;
855
856         return 0;
857
858  fail:
859         free_netdev(ndev);
860         return ret;
861 }
862
863 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
864 {
865         ASSERT_RTNL();
866
867         mutex_lock(&sdata->local->iflist_mtx);
868         list_del_rcu(&sdata->list);
869         mutex_unlock(&sdata->local->iflist_mtx);
870
871         synchronize_rcu();
872         unregister_netdevice(sdata->dev);
873 }
874
875 /*
876  * Remove all interfaces, may only be called at hardware unregistration
877  * time because it doesn't do RCU-safe list removals.
878  */
879 void ieee80211_remove_interfaces(struct ieee80211_local *local)
880 {
881         struct ieee80211_sub_if_data *sdata, *tmp;
882
883         ASSERT_RTNL();
884
885         list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
886                 /*
887                  * we cannot hold the iflist_mtx across unregister_netdevice,
888                  * but we only need to hold it for list modifications to lock
889                  * out readers since we're under the RTNL here as all other
890                  * writers.
891                  */
892                 mutex_lock(&local->iflist_mtx);
893                 list_del(&sdata->list);
894                 mutex_unlock(&local->iflist_mtx);
895
896                 unregister_netdevice(sdata->dev);
897         }
898 }
899
900 static u32 ieee80211_idle_off(struct ieee80211_local *local,
901                               const char *reason)
902 {
903         if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
904                 return 0;
905
906 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
907         printk(KERN_DEBUG "%s: device no longer idle - %s\n",
908                wiphy_name(local->hw.wiphy), reason);
909 #endif
910
911         local->hw.conf.flags &= ~IEEE80211_CONF_IDLE;
912         return IEEE80211_CONF_CHANGE_IDLE;
913 }
914
915 static u32 ieee80211_idle_on(struct ieee80211_local *local)
916 {
917         if (local->hw.conf.flags & IEEE80211_CONF_IDLE)
918                 return 0;
919
920 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
921         printk(KERN_DEBUG "%s: device now idle\n",
922                wiphy_name(local->hw.wiphy));
923 #endif
924
925         local->hw.conf.flags |= IEEE80211_CONF_IDLE;
926         return IEEE80211_CONF_CHANGE_IDLE;
927 }
928
929 u32 __ieee80211_recalc_idle(struct ieee80211_local *local)
930 {
931         struct ieee80211_sub_if_data *sdata;
932         int count = 0;
933
934         if (local->hw_scanning || local->sw_scanning)
935                 return ieee80211_idle_off(local, "scanning");
936
937         list_for_each_entry(sdata, &local->interfaces, list) {
938                 if (!netif_running(sdata->dev))
939                         continue;
940                 /* do not count disabled managed interfaces */
941                 if (sdata->vif.type == NL80211_IFTYPE_STATION &&
942                     sdata->u.mgd.state == IEEE80211_STA_MLME_DISABLED)
943                         continue;
944                 /* do not count unused IBSS interfaces */
945                 if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
946                     !sdata->u.ibss.ssid_len)
947                         continue;
948                 /* count everything else */
949                 count++;
950         }
951
952         if (!count)
953                 return ieee80211_idle_on(local);
954         else
955                 return ieee80211_idle_off(local, "in use");
956
957         return 0;
958 }
959
960 void ieee80211_recalc_idle(struct ieee80211_local *local)
961 {
962         u32 chg;
963
964         mutex_lock(&local->iflist_mtx);
965         chg = __ieee80211_recalc_idle(local);
966         mutex_unlock(&local->iflist_mtx);
967         if (chg)
968                 ieee80211_hw_config(local, chg);
969 }