main.c revision c951ad3550ab40071bb0f222ba6125845769c08a 
1/*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <net/mac80211.h>
12#include <net/ieee80211_radiotap.h>
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/netdevice.h>
16#include <linux/types.h>
17#include <linux/slab.h>
18#include <linux/skbuff.h>
19#include <linux/etherdevice.h>
20#include <linux/if_arp.h>
21#include <linux/wireless.h>
22#include <linux/rtnetlink.h>
23#include <linux/bitmap.h>
24#include <linux/pm_qos_params.h>
25#include <net/net_namespace.h>
26#include <net/cfg80211.h>
27
28#include "ieee80211_i.h"
29#include "driver-ops.h"
30#include "rate.h"
31#include "mesh.h"
32#include "wep.h"
33#include "wme.h"
34#include "aes_ccm.h"
35#include "led.h"
36#include "cfg.h"
37#include "debugfs.h"
38#include "debugfs_netdev.h"
39
40/*
41 * For seeing transmitted packets on monitor interfaces
42 * we have a radiotap header too.
43 */
44struct ieee80211_tx_status_rtap_hdr {
45	struct ieee80211_radiotap_header hdr;
46	u8 rate;
47	u8 padding_for_rate;
48	__le16 tx_flags;
49	u8 data_retries;
50} __attribute__ ((packed));
51
52
53void ieee80211_configure_filter(struct ieee80211_local *local)
54{
55	u64 mc;
56	unsigned int changed_flags;
57	unsigned int new_flags = 0;
58
59	if (atomic_read(&local->iff_promiscs))
60		new_flags |= FIF_PROMISC_IN_BSS;
61
62	if (atomic_read(&local->iff_allmultis))
63		new_flags |= FIF_ALLMULTI;
64
65	if (local->monitors || local->scanning)
66		new_flags |= FIF_BCN_PRBRESP_PROMISC;
67
68	if (local->fif_fcsfail)
69		new_flags |= FIF_FCSFAIL;
70
71	if (local->fif_plcpfail)
72		new_flags |= FIF_PLCPFAIL;
73
74	if (local->fif_control)
75		new_flags |= FIF_CONTROL;
76
77	if (local->fif_other_bss)
78		new_flags |= FIF_OTHER_BSS;
79
80	if (local->fif_pspoll)
81		new_flags |= FIF_PSPOLL;
82
83	spin_lock_bh(&local->filter_lock);
84	changed_flags = local->filter_flags ^ new_flags;
85
86	mc = drv_prepare_multicast(local, local->mc_count, local->mc_list);
87	spin_unlock_bh(&local->filter_lock);
88
89	/* be a bit nasty */
90	new_flags |= (1<<31);
91
92	drv_configure_filter(local, changed_flags, &new_flags, mc);
93
94	WARN_ON(new_flags & (1<<31));
95
96	local->filter_flags = new_flags & ~(1<<31);
97}
98
99static void ieee80211_reconfig_filter(struct work_struct *work)
100{
101	struct ieee80211_local *local =
102		container_of(work, struct ieee80211_local, reconfig_filter);
103
104	ieee80211_configure_filter(local);
105}
106
107int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
108{
109	struct ieee80211_channel *chan, *scan_chan;
110	int ret = 0;
111	int power;
112	enum nl80211_channel_type channel_type;
113
114	might_sleep();
115
116	scan_chan = local->scan_channel;
117
118	if (scan_chan) {
119		chan = scan_chan;
120		channel_type = NL80211_CHAN_NO_HT;
121	} else {
122		chan = local->oper_channel;
123		channel_type = local->oper_channel_type;
124	}
125
126	if (chan != local->hw.conf.channel ||
127	    channel_type != local->hw.conf.channel_type) {
128		local->hw.conf.channel = chan;
129		local->hw.conf.channel_type = channel_type;
130		changed |= IEEE80211_CONF_CHANGE_CHANNEL;
131	}
132
133	if (scan_chan)
134		power = chan->max_power;
135	else
136		power = local->power_constr_level ?
137			(chan->max_power - local->power_constr_level) :
138			chan->max_power;
139
140	if (local->user_power_level >= 0)
141		power = min(power, local->user_power_level);
142
143	if (local->hw.conf.power_level != power) {
144		changed |= IEEE80211_CONF_CHANGE_POWER;
145		local->hw.conf.power_level = power;
146	}
147
148	if (changed && local->open_count) {
149		ret = drv_config(local, changed);
150		/*
151		 * Goal:
152		 * HW reconfiguration should never fail, the driver has told
153		 * us what it can support so it should live up to that promise.
154		 *
155		 * Current status:
156		 * rfkill is not integrated with mac80211 and a
157		 * configuration command can thus fail if hardware rfkill
158		 * is enabled
159		 *
160		 * FIXME: integrate rfkill with mac80211 and then add this
161		 * WARN_ON() back
162		 *
163		 */
164		/* WARN_ON(ret); */
165	}
166
167	return ret;
168}
169
170void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
171				      u32 changed)
172{
173	struct ieee80211_local *local = sdata->local;
174	static const u8 zero[ETH_ALEN] = { 0 };
175
176	if (!changed)
177		return;
178
179	if (sdata->vif.type == NL80211_IFTYPE_STATION) {
180		/*
181		 * While not associated, claim a BSSID of all-zeroes
182		 * so that drivers don't do any weird things with the
183		 * BSSID at that time.
184		 */
185		if (sdata->vif.bss_conf.assoc)
186			sdata->vif.bss_conf.bssid = sdata->u.mgd.bssid;
187		else
188			sdata->vif.bss_conf.bssid = zero;
189	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
190		sdata->vif.bss_conf.bssid = sdata->u.ibss.bssid;
191	else if (sdata->vif.type == NL80211_IFTYPE_AP)
192		sdata->vif.bss_conf.bssid = sdata->dev->dev_addr;
193	else if (ieee80211_vif_is_mesh(&sdata->vif)) {
194		sdata->vif.bss_conf.bssid = zero;
195	} else {
196		WARN_ON(1);
197		return;
198	}
199
200	switch (sdata->vif.type) {
201	case NL80211_IFTYPE_AP:
202	case NL80211_IFTYPE_ADHOC:
203	case NL80211_IFTYPE_MESH_POINT:
204		break;
205	default:
206		/* do not warn to simplify caller in scan.c */
207		changed &= ~BSS_CHANGED_BEACON_ENABLED;
208		if (WARN_ON(changed & BSS_CHANGED_BEACON))
209			return;
210		break;
211	}
212
213	if (changed & BSS_CHANGED_BEACON_ENABLED) {
214		if (local->quiescing || !netif_running(sdata->dev) ||
215		    test_bit(SCAN_SW_SCANNING, &local->scanning)) {
216			sdata->vif.bss_conf.enable_beacon = false;
217		} else {
218			/*
219			 * Beacon should be enabled, but AP mode must
220			 * check whether there is a beacon configured.
221			 */
222			switch (sdata->vif.type) {
223			case NL80211_IFTYPE_AP:
224				sdata->vif.bss_conf.enable_beacon =
225					!!rcu_dereference(sdata->u.ap.beacon);
226				break;
227			case NL80211_IFTYPE_ADHOC:
228				sdata->vif.bss_conf.enable_beacon =
229					!!rcu_dereference(sdata->u.ibss.presp);
230				break;
231			case NL80211_IFTYPE_MESH_POINT:
232				sdata->vif.bss_conf.enable_beacon = true;
233				break;
234			default:
235				/* not reached */
236				WARN_ON(1);
237				break;
238			}
239		}
240	}
241
242	drv_bss_info_changed(local, &sdata->vif,
243			     &sdata->vif.bss_conf, changed);
244}
245
246u32 ieee80211_reset_erp_info(struct ieee80211_sub_if_data *sdata)
247{
248	sdata->vif.bss_conf.use_cts_prot = false;
249	sdata->vif.bss_conf.use_short_preamble = false;
250	sdata->vif.bss_conf.use_short_slot = false;
251	return BSS_CHANGED_ERP_CTS_PROT |
252	       BSS_CHANGED_ERP_PREAMBLE |
253	       BSS_CHANGED_ERP_SLOT;
254}
255
256void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
257				 struct sk_buff *skb)
258{
259	struct ieee80211_local *local = hw_to_local(hw);
260	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
261	int tmp;
262
263	skb->pkt_type = IEEE80211_TX_STATUS_MSG;
264	skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
265		       &local->skb_queue : &local->skb_queue_unreliable, skb);
266	tmp = skb_queue_len(&local->skb_queue) +
267		skb_queue_len(&local->skb_queue_unreliable);
268	while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
269	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
270		dev_kfree_skb_irq(skb);
271		tmp--;
272		I802_DEBUG_INC(local->tx_status_drop);
273	}
274	tasklet_schedule(&local->tasklet);
275}
276EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
277
278static void ieee80211_tasklet_handler(unsigned long data)
279{
280	struct ieee80211_local *local = (struct ieee80211_local *) data;
281	struct sk_buff *skb;
282	struct ieee80211_ra_tid *ra_tid;
283
284	while ((skb = skb_dequeue(&local->skb_queue)) ||
285	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
286		switch (skb->pkt_type) {
287		case IEEE80211_RX_MSG:
288			/* Clear skb->pkt_type in order to not confuse kernel
289			 * netstack. */
290			skb->pkt_type = 0;
291			ieee80211_rx(local_to_hw(local), skb);
292			break;
293		case IEEE80211_TX_STATUS_MSG:
294			skb->pkt_type = 0;
295			ieee80211_tx_status(local_to_hw(local), skb);
296			break;
297		case IEEE80211_DELBA_MSG:
298			ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
299			ieee80211_stop_tx_ba_cb(ra_tid->vif, ra_tid->ra,
300						ra_tid->tid);
301			dev_kfree_skb(skb);
302			break;
303		case IEEE80211_ADDBA_MSG:
304			ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
305			ieee80211_start_tx_ba_cb(ra_tid->vif, ra_tid->ra,
306						 ra_tid->tid);
307			dev_kfree_skb(skb);
308			break ;
309		default:
310			WARN(1, "mac80211: Packet is of unknown type %d\n",
311			     skb->pkt_type);
312			dev_kfree_skb(skb);
313			break;
314		}
315	}
316}
317
318static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
319					    struct sta_info *sta,
320					    struct sk_buff *skb)
321{
322	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
323
324	/*
325	 * XXX: This is temporary!
326	 *
327	 *	The problem here is that when we get here, the driver will
328	 *	quite likely have pretty much overwritten info->control by
329	 *	using info->driver_data or info->rate_driver_data. Thus,
330	 *	when passing out the frame to the driver again, we would be
331	 *	passing completely bogus data since the driver would then
332	 *	expect a properly filled info->control. In mac80211 itself
333	 *	the same problem occurs, since we need info->control.vif
334	 *	internally.
335	 *
336	 *	To fix this, we should send the frame through TX processing
337	 *	again. However, it's not that simple, since the frame will
338	 *	have been software-encrypted (if applicable) already, and
339	 *	encrypting it again doesn't do much good. So to properly do
340	 *	that, we not only have to skip the actual 'raw' encryption
341	 *	(key selection etc. still has to be done!) but also the
342	 *	sequence number assignment since that impacts the crypto
343	 *	encapsulation, of course.
344	 *
345	 *	Hence, for now, fix the bug by just dropping the frame.
346	 */
347	goto drop;
348
349	sta->tx_filtered_count++;
350
351	/*
352	 * Clear the TX filter mask for this STA when sending the next
353	 * packet. If the STA went to power save mode, this will happen
354	 * when it wakes up for the next time.
355	 */
356	set_sta_flags(sta, WLAN_STA_CLEAR_PS_FILT);
357
358	/*
359	 * This code races in the following way:
360	 *
361	 *  (1) STA sends frame indicating it will go to sleep and does so
362	 *  (2) hardware/firmware adds STA to filter list, passes frame up
363	 *  (3) hardware/firmware processes TX fifo and suppresses a frame
364	 *  (4) we get TX status before having processed the frame and
365	 *	knowing that the STA has gone to sleep.
366	 *
367	 * This is actually quite unlikely even when both those events are
368	 * processed from interrupts coming in quickly after one another or
369	 * even at the same time because we queue both TX status events and
370	 * RX frames to be processed by a tasklet and process them in the
371	 * same order that they were received or TX status last. Hence, there
372	 * is no race as long as the frame RX is processed before the next TX
373	 * status, which drivers can ensure, see below.
374	 *
375	 * Note that this can only happen if the hardware or firmware can
376	 * actually add STAs to the filter list, if this is done by the
377	 * driver in response to set_tim() (which will only reduce the race
378	 * this whole filtering tries to solve, not completely solve it)
379	 * this situation cannot happen.
380	 *
381	 * To completely solve this race drivers need to make sure that they
382	 *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
383	 *	functions and
384	 *  (b) always process RX events before TX status events if ordering
385	 *      can be unknown, for example with different interrupt status
386	 *	bits.
387	 */
388	if (test_sta_flags(sta, WLAN_STA_PS_STA) &&
389	    skb_queue_len(&sta->tx_filtered) < STA_MAX_TX_BUFFER) {
390		skb_queue_tail(&sta->tx_filtered, skb);
391		return;
392	}
393
394	if (!test_sta_flags(sta, WLAN_STA_PS_STA) &&
395	    !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
396		/* Software retry the packet once */
397		info->flags |= IEEE80211_TX_INTFL_RETRIED;
398		ieee80211_add_pending_skb(local, skb);
399		return;
400	}
401
402 drop:
403#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
404	if (net_ratelimit())
405		printk(KERN_DEBUG "%s: dropped TX filtered frame, "
406		       "queue_len=%d PS=%d @%lu\n",
407		       wiphy_name(local->hw.wiphy),
408		       skb_queue_len(&sta->tx_filtered),
409		       !!test_sta_flags(sta, WLAN_STA_PS_STA), jiffies);
410#endif
411	dev_kfree_skb(skb);
412}
413
414void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
415{
416	struct sk_buff *skb2;
417	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
418	struct ieee80211_local *local = hw_to_local(hw);
419	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
420	u16 frag, type;
421	__le16 fc;
422	struct ieee80211_supported_band *sband;
423	struct ieee80211_tx_status_rtap_hdr *rthdr;
424	struct ieee80211_sub_if_data *sdata;
425	struct net_device *prev_dev = NULL;
426	struct sta_info *sta;
427	int retry_count = -1, i;
428
429	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
430		/* the HW cannot have attempted that rate */
431		if (i >= hw->max_rates) {
432			info->status.rates[i].idx = -1;
433			info->status.rates[i].count = 0;
434		}
435
436		retry_count += info->status.rates[i].count;
437	}
438	if (retry_count < 0)
439		retry_count = 0;
440
441	rcu_read_lock();
442
443	sband = local->hw.wiphy->bands[info->band];
444
445	sta = sta_info_get(local, hdr->addr1);
446
447	if (sta) {
448		if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
449		    test_sta_flags(sta, WLAN_STA_PS_STA)) {
450			/*
451			 * The STA is in power save mode, so assume
452			 * that this TX packet failed because of that.
453			 */
454			ieee80211_handle_filtered_frame(local, sta, skb);
455			rcu_read_unlock();
456			return;
457		}
458
459		fc = hdr->frame_control;
460
461		if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
462		    (ieee80211_is_data_qos(fc))) {
463			u16 tid, ssn;
464			u8 *qc;
465
466			qc = ieee80211_get_qos_ctl(hdr);
467			tid = qc[0] & 0xf;
468			ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
469						& IEEE80211_SCTL_SEQ);
470			ieee80211_send_bar(sta->sdata, hdr->addr1,
471					   tid, ssn);
472		}
473
474		if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
475			ieee80211_handle_filtered_frame(local, sta, skb);
476			rcu_read_unlock();
477			return;
478		} else {
479			if (!(info->flags & IEEE80211_TX_STAT_ACK))
480				sta->tx_retry_failed++;
481			sta->tx_retry_count += retry_count;
482		}
483
484		rate_control_tx_status(local, sband, sta, skb);
485		if (ieee80211_vif_is_mesh(&sta->sdata->vif))
486			ieee80211s_update_metric(local, sta, skb);
487	}
488
489	rcu_read_unlock();
490
491	ieee80211_led_tx(local, 0);
492
493	/* SNMP counters
494	 * Fragments are passed to low-level drivers as separate skbs, so these
495	 * are actually fragments, not frames. Update frame counters only for
496	 * the first fragment of the frame. */
497
498	frag = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG;
499	type = le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_FTYPE;
500
501	if (info->flags & IEEE80211_TX_STAT_ACK) {
502		if (frag == 0) {
503			local->dot11TransmittedFrameCount++;
504			if (is_multicast_ether_addr(hdr->addr1))
505				local->dot11MulticastTransmittedFrameCount++;
506			if (retry_count > 0)
507				local->dot11RetryCount++;
508			if (retry_count > 1)
509				local->dot11MultipleRetryCount++;
510		}
511
512		/* This counter shall be incremented for an acknowledged MPDU
513		 * with an individual address in the address 1 field or an MPDU
514		 * with a multicast address in the address 1 field of type Data
515		 * or Management. */
516		if (!is_multicast_ether_addr(hdr->addr1) ||
517		    type == IEEE80211_FTYPE_DATA ||
518		    type == IEEE80211_FTYPE_MGMT)
519			local->dot11TransmittedFragmentCount++;
520	} else {
521		if (frag == 0)
522			local->dot11FailedCount++;
523	}
524
525	/* this was a transmitted frame, but now we want to reuse it */
526	skb_orphan(skb);
527
528	/*
529	 * This is a bit racy but we can avoid a lot of work
530	 * with this test...
531	 */
532	if (!local->monitors && !local->cooked_mntrs) {
533		dev_kfree_skb(skb);
534		return;
535	}
536
537	/* send frame to monitor interfaces now */
538
539	if (skb_headroom(skb) < sizeof(*rthdr)) {
540		printk(KERN_ERR "ieee80211_tx_status: headroom too small\n");
541		dev_kfree_skb(skb);
542		return;
543	}
544
545	rthdr = (struct ieee80211_tx_status_rtap_hdr *)
546				skb_push(skb, sizeof(*rthdr));
547
548	memset(rthdr, 0, sizeof(*rthdr));
549	rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
550	rthdr->hdr.it_present =
551		cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
552			    (1 << IEEE80211_RADIOTAP_DATA_RETRIES) |
553			    (1 << IEEE80211_RADIOTAP_RATE));
554
555	if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
556	    !is_multicast_ether_addr(hdr->addr1))
557		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_FAIL);
558
559	/*
560	 * XXX: Once radiotap gets the bitmap reset thing the vendor
561	 *	extensions proposal contains, we can actually report
562	 *	the whole set of tries we did.
563	 */
564	if ((info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
565	    (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
566		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_CTS);
567	else if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
568		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_RTS);
569	if (info->status.rates[0].idx >= 0 &&
570	    !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS))
571		rthdr->rate = sband->bitrates[
572				info->status.rates[0].idx].bitrate / 5;
573
574	/* for now report the total retry_count */
575	rthdr->data_retries = retry_count;
576
577	/* XXX: is this sufficient for BPF? */
578	skb_set_mac_header(skb, 0);
579	skb->ip_summed = CHECKSUM_UNNECESSARY;
580	skb->pkt_type = PACKET_OTHERHOST;
581	skb->protocol = htons(ETH_P_802_2);
582	memset(skb->cb, 0, sizeof(skb->cb));
583
584	rcu_read_lock();
585	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
586		if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
587			if (!netif_running(sdata->dev))
588				continue;
589
590			if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
591			    !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
592			    (type == IEEE80211_FTYPE_DATA))
593				continue;
594
595			if (prev_dev) {
596				skb2 = skb_clone(skb, GFP_ATOMIC);
597				if (skb2) {
598					skb2->dev = prev_dev;
599					netif_rx(skb2);
600				}
601			}
602
603			prev_dev = sdata->dev;
604		}
605	}
606	if (prev_dev) {
607		skb->dev = prev_dev;
608		netif_rx(skb);
609		skb = NULL;
610	}
611	rcu_read_unlock();
612	dev_kfree_skb(skb);
613}
614EXPORT_SYMBOL(ieee80211_tx_status);
615
616static void ieee80211_restart_work(struct work_struct *work)
617{
618	struct ieee80211_local *local =
619		container_of(work, struct ieee80211_local, restart_work);
620
621	rtnl_lock();
622	ieee80211_reconfig(local);
623	rtnl_unlock();
624}
625
626void ieee80211_restart_hw(struct ieee80211_hw *hw)
627{
628	struct ieee80211_local *local = hw_to_local(hw);
629
630	/* use this reason, __ieee80211_resume will unblock it */
631	ieee80211_stop_queues_by_reason(hw,
632		IEEE80211_QUEUE_STOP_REASON_SUSPEND);
633
634	schedule_work(&local->restart_work);
635}
636EXPORT_SYMBOL(ieee80211_restart_hw);
637
638struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
639					const struct ieee80211_ops *ops)
640{
641	struct ieee80211_local *local;
642	int priv_size, i;
643	struct wiphy *wiphy;
644
645	/* Ensure 32-byte alignment of our private data and hw private data.
646	 * We use the wiphy priv data for both our ieee80211_local and for
647	 * the driver's private data
648	 *
649	 * In memory it'll be like this:
650	 *
651	 * +-------------------------+
652	 * | struct wiphy	    |
653	 * +-------------------------+
654	 * | struct ieee80211_local  |
655	 * +-------------------------+
656	 * | driver's private data   |
657	 * +-------------------------+
658	 *
659	 */
660	priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
661
662	wiphy = wiphy_new(&mac80211_config_ops, priv_size);
663
664	if (!wiphy)
665		return NULL;
666
667	wiphy->netnsok = true;
668	wiphy->privid = mac80211_wiphy_privid;
669
670	/* Yes, putting cfg80211_bss into ieee80211_bss is a hack */
671	wiphy->bss_priv_size = sizeof(struct ieee80211_bss) -
672			       sizeof(struct cfg80211_bss);
673
674	local = wiphy_priv(wiphy);
675
676	local->hw.wiphy = wiphy;
677
678	local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
679
680	BUG_ON(!ops->tx);
681	BUG_ON(!ops->start);
682	BUG_ON(!ops->stop);
683	BUG_ON(!ops->config);
684	BUG_ON(!ops->add_interface);
685	BUG_ON(!ops->remove_interface);
686	BUG_ON(!ops->configure_filter);
687	local->ops = ops;
688
689	/* set up some defaults */
690	local->hw.queues = 1;
691	local->hw.max_rates = 1;
692	local->hw.conf.long_frame_max_tx_count = wiphy->retry_long;
693	local->hw.conf.short_frame_max_tx_count = wiphy->retry_short;
694	local->user_power_level = -1;
695
696	INIT_LIST_HEAD(&local->interfaces);
697	mutex_init(&local->iflist_mtx);
698	mutex_init(&local->scan_mtx);
699
700	spin_lock_init(&local->key_lock);
701	spin_lock_init(&local->filter_lock);
702	spin_lock_init(&local->queue_stop_reason_lock);
703
704	INIT_DELAYED_WORK(&local->scan_work, ieee80211_scan_work);
705
706	INIT_WORK(&local->restart_work, ieee80211_restart_work);
707
708	INIT_WORK(&local->reconfig_filter, ieee80211_reconfig_filter);
709
710	INIT_WORK(&local->dynamic_ps_enable_work,
711		  ieee80211_dynamic_ps_enable_work);
712	INIT_WORK(&local->dynamic_ps_disable_work,
713		  ieee80211_dynamic_ps_disable_work);
714	setup_timer(&local->dynamic_ps_timer,
715		    ieee80211_dynamic_ps_timer, (unsigned long) local);
716
717	sta_info_init(local);
718
719	for (i = 0; i < IEEE80211_MAX_QUEUES; i++)
720		skb_queue_head_init(&local->pending[i]);
721	tasklet_init(&local->tx_pending_tasklet, ieee80211_tx_pending,
722		     (unsigned long)local);
723
724	tasklet_init(&local->tasklet,
725		     ieee80211_tasklet_handler,
726		     (unsigned long) local);
727
728	skb_queue_head_init(&local->skb_queue);
729	skb_queue_head_init(&local->skb_queue_unreliable);
730
731	spin_lock_init(&local->ampdu_lock);
732
733	return local_to_hw(local);
734}
735EXPORT_SYMBOL(ieee80211_alloc_hw);
736
737int ieee80211_register_hw(struct ieee80211_hw *hw)
738{
739	struct ieee80211_local *local = hw_to_local(hw);
740	int result;
741	enum ieee80211_band band;
742	int channels, i, j, max_bitrates;
743	bool supp_ht;
744	static const u32 cipher_suites[] = {
745		WLAN_CIPHER_SUITE_WEP40,
746		WLAN_CIPHER_SUITE_WEP104,
747		WLAN_CIPHER_SUITE_TKIP,
748		WLAN_CIPHER_SUITE_CCMP,
749
750		/* keep last -- depends on hw flags! */
751		WLAN_CIPHER_SUITE_AES_CMAC
752	};
753
754	/*
755	 * generic code guarantees at least one band,
756	 * set this very early because much code assumes
757	 * that hw.conf.channel is assigned
758	 */
759	channels = 0;
760	max_bitrates = 0;
761	supp_ht = false;
762	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
763		struct ieee80211_supported_band *sband;
764
765		sband = local->hw.wiphy->bands[band];
766		if (!sband)
767			continue;
768		if (!local->oper_channel) {
769			/* init channel we're on */
770			local->hw.conf.channel =
771			local->oper_channel = &sband->channels[0];
772			local->hw.conf.channel_type = NL80211_CHAN_NO_HT;
773		}
774		channels += sband->n_channels;
775
776		if (max_bitrates < sband->n_bitrates)
777			max_bitrates = sband->n_bitrates;
778		supp_ht = supp_ht || sband->ht_cap.ht_supported;
779	}
780
781	local->int_scan_req = kzalloc(sizeof(*local->int_scan_req) +
782				      sizeof(void *) * channels, GFP_KERNEL);
783	if (!local->int_scan_req)
784		return -ENOMEM;
785
786	/* if low-level driver supports AP, we also support VLAN */
787	if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_AP))
788		local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_AP_VLAN);
789
790	/* mac80211 always supports monitor */
791	local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_MONITOR);
792
793	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
794		local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
795	else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
796		local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_UNSPEC;
797
798	/*
799	 * Calculate scan IE length -- we need this to alloc
800	 * memory and to subtract from the driver limit. It
801	 * includes the (extended) supported rates and HT
802	 * information -- SSID is the driver's responsibility.
803	 */
804	local->scan_ies_len = 4 + max_bitrates; /* (ext) supp rates */
805	if (supp_ht)
806		local->scan_ies_len += 2 + sizeof(struct ieee80211_ht_cap);
807
808	if (!local->ops->hw_scan) {
809		/* For hw_scan, driver needs to set these up. */
810		local->hw.wiphy->max_scan_ssids = 4;
811		local->hw.wiphy->max_scan_ie_len = IEEE80211_MAX_DATA_LEN;
812	}
813
814	/*
815	 * If the driver supports any scan IEs, then assume the
816	 * limit includes the IEs mac80211 will add, otherwise
817	 * leave it at zero and let the driver sort it out; we
818	 * still pass our IEs to the driver but userspace will
819	 * not be allowed to in that case.
820	 */
821	if (local->hw.wiphy->max_scan_ie_len)
822		local->hw.wiphy->max_scan_ie_len -= local->scan_ies_len;
823
824	local->hw.wiphy->cipher_suites = cipher_suites;
825	local->hw.wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);
826	if (!(local->hw.flags & IEEE80211_HW_MFP_CAPABLE))
827		local->hw.wiphy->n_cipher_suites--;
828
829	result = wiphy_register(local->hw.wiphy);
830	if (result < 0)
831		goto fail_wiphy_register;
832
833	/*
834	 * We use the number of queues for feature tests (QoS, HT) internally
835	 * so restrict them appropriately.
836	 */
837	if (hw->queues > IEEE80211_MAX_QUEUES)
838		hw->queues = IEEE80211_MAX_QUEUES;
839
840	local->workqueue =
841		create_singlethread_workqueue(wiphy_name(local->hw.wiphy));
842	if (!local->workqueue) {
843		result = -ENOMEM;
844		goto fail_workqueue;
845	}
846
847	/*
848	 * The hardware needs headroom for sending the frame,
849	 * and we need some headroom for passing the frame to monitor
850	 * interfaces, but never both at the same time.
851	 */
852	local->tx_headroom = max_t(unsigned int , local->hw.extra_tx_headroom,
853				   sizeof(struct ieee80211_tx_status_rtap_hdr));
854
855	debugfs_hw_add(local);
856
857	if (local->hw.max_listen_interval == 0)
858		local->hw.max_listen_interval = 1;
859
860	local->hw.conf.listen_interval = local->hw.max_listen_interval;
861
862	result = sta_info_start(local);
863	if (result < 0)
864		goto fail_sta_info;
865
866	result = ieee80211_wep_init(local);
867	if (result < 0) {
868		printk(KERN_DEBUG "%s: Failed to initialize wep: %d\n",
869		       wiphy_name(local->hw.wiphy), result);
870		goto fail_wep;
871	}
872
873	rtnl_lock();
874
875	result = ieee80211_init_rate_ctrl_alg(local,
876					      hw->rate_control_algorithm);
877	if (result < 0) {
878		printk(KERN_DEBUG "%s: Failed to initialize rate control "
879		       "algorithm\n", wiphy_name(local->hw.wiphy));
880		goto fail_rate;
881	}
882
883	/* add one default STA interface if supported */
884	if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_STATION)) {
885		result = ieee80211_if_add(local, "wlan%d", NULL,
886					  NL80211_IFTYPE_STATION, NULL);
887		if (result)
888			printk(KERN_WARNING "%s: Failed to add default virtual iface\n",
889			       wiphy_name(local->hw.wiphy));
890	}
891
892	rtnl_unlock();
893
894	ieee80211_led_init(local);
895
896	/* alloc internal scan request */
897	i = 0;
898	local->int_scan_req->ssids = &local->scan_ssid;
899	local->int_scan_req->n_ssids = 1;
900	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
901		if (!hw->wiphy->bands[band])
902			continue;
903		for (j = 0; j < hw->wiphy->bands[band]->n_channels; j++) {
904			local->int_scan_req->channels[i] =
905				&hw->wiphy->bands[band]->channels[j];
906			i++;
907		}
908	}
909	local->int_scan_req->n_channels = i;
910
911	local->network_latency_notifier.notifier_call =
912		ieee80211_max_network_latency;
913	result = pm_qos_add_notifier(PM_QOS_NETWORK_LATENCY,
914				     &local->network_latency_notifier);
915
916	if (result) {
917		rtnl_lock();
918		goto fail_pm_qos;
919	}
920
921	return 0;
922
923 fail_pm_qos:
924	ieee80211_led_exit(local);
925	ieee80211_remove_interfaces(local);
926 fail_rate:
927	rtnl_unlock();
928	ieee80211_wep_free(local);
929 fail_wep:
930	sta_info_stop(local);
931 fail_sta_info:
932	destroy_workqueue(local->workqueue);
933 fail_workqueue:
934	wiphy_unregister(local->hw.wiphy);
935 fail_wiphy_register:
936	kfree(local->int_scan_req);
937	return result;
938}
939EXPORT_SYMBOL(ieee80211_register_hw);
940
941void ieee80211_unregister_hw(struct ieee80211_hw *hw)
942{
943	struct ieee80211_local *local = hw_to_local(hw);
944
945	tasklet_kill(&local->tx_pending_tasklet);
946	tasklet_kill(&local->tasklet);
947
948	pm_qos_remove_notifier(PM_QOS_NETWORK_LATENCY,
949			       &local->network_latency_notifier);
950
951	rtnl_lock();
952
953	/*
954	 * At this point, interface list manipulations are fine
955	 * because the driver cannot be handing us frames any
956	 * more and the tasklet is killed.
957	 */
958	ieee80211_remove_interfaces(local);
959
960	rtnl_unlock();
961
962	cancel_work_sync(&local->reconfig_filter);
963
964	ieee80211_clear_tx_pending(local);
965	sta_info_stop(local);
966	rate_control_deinitialize(local);
967
968	if (skb_queue_len(&local->skb_queue)
969			|| skb_queue_len(&local->skb_queue_unreliable))
970		printk(KERN_WARNING "%s: skb_queue not empty\n",
971		       wiphy_name(local->hw.wiphy));
972	skb_queue_purge(&local->skb_queue);
973	skb_queue_purge(&local->skb_queue_unreliable);
974
975	destroy_workqueue(local->workqueue);
976	wiphy_unregister(local->hw.wiphy);
977	ieee80211_wep_free(local);
978	ieee80211_led_exit(local);
979	kfree(local->int_scan_req);
980}
981EXPORT_SYMBOL(ieee80211_unregister_hw);
982
983void ieee80211_free_hw(struct ieee80211_hw *hw)
984{
985	struct ieee80211_local *local = hw_to_local(hw);
986
987	mutex_destroy(&local->iflist_mtx);
988	mutex_destroy(&local->scan_mtx);
989
990	wiphy_free(local->hw.wiphy);
991}
992EXPORT_SYMBOL(ieee80211_free_hw);
993
994static int __init ieee80211_init(void)
995{
996	struct sk_buff *skb;
997	int ret;
998
999	BUILD_BUG_ON(sizeof(struct ieee80211_tx_info) > sizeof(skb->cb));
1000	BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, driver_data) +
1001		     IEEE80211_TX_INFO_DRIVER_DATA_SIZE > sizeof(skb->cb));
1002
1003	ret = rc80211_minstrel_init();
1004	if (ret)
1005		return ret;
1006
1007	ret = rc80211_pid_init();
1008	if (ret)
1009		return ret;
1010
1011	ieee80211_debugfs_netdev_init();
1012
1013	return 0;
1014}
1015
1016static void __exit ieee80211_exit(void)
1017{
1018	rc80211_pid_exit();
1019	rc80211_minstrel_exit();
1020
1021	/*
1022	 * For key todo, it'll be empty by now but the work
1023	 * might still be scheduled.
1024	 */
1025	flush_scheduled_work();
1026
1027	if (mesh_allocated)
1028		ieee80211s_stop();
1029
1030	ieee80211_debugfs_netdev_exit();
1031}
1032
1033
1034subsys_initcall(ieee80211_init);
1035module_exit(ieee80211_exit);
1036
1037MODULE_DESCRIPTION("IEEE 802.11 subsystem");
1038MODULE_LICENSE("GPL");
1039