xref: /linux/net/mac80211/main.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
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  */
44 struct 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 
53 /* must be called under mdev tx lock */
54 void ieee80211_configure_filter(struct ieee80211_local *local)
55 {
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)
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 	changed_flags = local->filter_flags ^ new_flags;
81 
82 	/* be a bit nasty */
83 	new_flags |= (1<<31);
84 
85 	drv_configure_filter(local, changed_flags, &new_flags,
86 			     local->mdev->mc_count,
87 			     local->mdev->mc_list);
88 
89 	WARN_ON(new_flags & (1<<31));
90 
91 	local->filter_flags = new_flags & ~(1<<31);
92 }
93 
94 /* master interface */
95 
96 static int header_parse_80211(const struct sk_buff *skb, unsigned char *haddr)
97 {
98 	memcpy(haddr, skb_mac_header(skb) + 10, ETH_ALEN); /* addr2 */
99 	return ETH_ALEN;
100 }
101 
102 static const struct header_ops ieee80211_header_ops = {
103 	.create		= eth_header,
104 	.parse		= header_parse_80211,
105 	.rebuild	= eth_rebuild_header,
106 	.cache		= eth_header_cache,
107 	.cache_update	= eth_header_cache_update,
108 };
109 
110 static int ieee80211_master_open(struct net_device *dev)
111 {
112 	struct ieee80211_master_priv *mpriv = netdev_priv(dev);
113 	struct ieee80211_local *local = mpriv->local;
114 	struct ieee80211_sub_if_data *sdata;
115 	int res = -EOPNOTSUPP;
116 
117 	/* we hold the RTNL here so can safely walk the list */
118 	list_for_each_entry(sdata, &local->interfaces, list) {
119 		if (netif_running(sdata->dev)) {
120 			res = 0;
121 			break;
122 		}
123 	}
124 
125 	if (res)
126 		return res;
127 
128 	netif_tx_start_all_queues(local->mdev);
129 
130 	return 0;
131 }
132 
133 static int ieee80211_master_stop(struct net_device *dev)
134 {
135 	struct ieee80211_master_priv *mpriv = netdev_priv(dev);
136 	struct ieee80211_local *local = mpriv->local;
137 	struct ieee80211_sub_if_data *sdata;
138 
139 	/* we hold the RTNL here so can safely walk the list */
140 	list_for_each_entry(sdata, &local->interfaces, list)
141 		if (netif_running(sdata->dev))
142 			dev_close(sdata->dev);
143 
144 	return 0;
145 }
146 
147 static void ieee80211_master_set_multicast_list(struct net_device *dev)
148 {
149 	struct ieee80211_master_priv *mpriv = netdev_priv(dev);
150 	struct ieee80211_local *local = mpriv->local;
151 
152 	ieee80211_configure_filter(local);
153 }
154 
155 int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
156 {
157 	struct ieee80211_channel *chan, *scan_chan;
158 	int ret = 0;
159 	int power;
160 	enum nl80211_channel_type channel_type;
161 
162 	might_sleep();
163 
164 	scan_chan = local->scan_channel;
165 
166 	if (scan_chan) {
167 		chan = scan_chan;
168 		channel_type = NL80211_CHAN_NO_HT;
169 	} else {
170 		chan = local->oper_channel;
171 		channel_type = local->oper_channel_type;
172 	}
173 
174 	if (chan != local->hw.conf.channel ||
175 	    channel_type != local->hw.conf.channel_type) {
176 		local->hw.conf.channel = chan;
177 		local->hw.conf.channel_type = channel_type;
178 		changed |= IEEE80211_CONF_CHANGE_CHANNEL;
179 	}
180 
181 	if (scan_chan)
182 		power = chan->max_power;
183 	else
184 		power = local->power_constr_level ?
185 			(chan->max_power - local->power_constr_level) :
186 			chan->max_power;
187 
188 	if (local->user_power_level >= 0)
189 		power = min(power, local->user_power_level);
190 
191 	if (local->hw.conf.power_level != power) {
192 		changed |= IEEE80211_CONF_CHANGE_POWER;
193 		local->hw.conf.power_level = power;
194 	}
195 
196 	if (changed && local->open_count) {
197 		ret = drv_config(local, changed);
198 		/*
199 		 * Goal:
200 		 * HW reconfiguration should never fail, the driver has told
201 		 * us what it can support so it should live up to that promise.
202 		 *
203 		 * Current status:
204 		 * rfkill is not integrated with mac80211 and a
205 		 * configuration command can thus fail if hardware rfkill
206 		 * is enabled
207 		 *
208 		 * FIXME: integrate rfkill with mac80211 and then add this
209 		 * WARN_ON() back
210 		 *
211 		 */
212 		/* WARN_ON(ret); */
213 	}
214 
215 	return ret;
216 }
217 
218 void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
219 				      u32 changed)
220 {
221 	struct ieee80211_local *local = sdata->local;
222 	static const u8 zero[ETH_ALEN] = { 0 };
223 
224 	if (!changed)
225 		return;
226 
227 	if (sdata->vif.type == NL80211_IFTYPE_STATION) {
228 		/*
229 		 * While not associated, claim a BSSID of all-zeroes
230 		 * so that drivers don't do any weird things with the
231 		 * BSSID at that time.
232 		 */
233 		if (sdata->vif.bss_conf.assoc)
234 			sdata->vif.bss_conf.bssid = sdata->u.mgd.bssid;
235 		else
236 			sdata->vif.bss_conf.bssid = zero;
237 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
238 		sdata->vif.bss_conf.bssid = sdata->u.ibss.bssid;
239 	else if (sdata->vif.type == NL80211_IFTYPE_AP)
240 		sdata->vif.bss_conf.bssid = sdata->dev->dev_addr;
241 	else if (ieee80211_vif_is_mesh(&sdata->vif)) {
242 		sdata->vif.bss_conf.bssid = zero;
243 	} else {
244 		WARN_ON(1);
245 		return;
246 	}
247 
248 	switch (sdata->vif.type) {
249 	case NL80211_IFTYPE_AP:
250 	case NL80211_IFTYPE_ADHOC:
251 	case NL80211_IFTYPE_MESH_POINT:
252 		break;
253 	default:
254 		/* do not warn to simplify caller in scan.c */
255 		changed &= ~BSS_CHANGED_BEACON_ENABLED;
256 		if (WARN_ON(changed & BSS_CHANGED_BEACON))
257 			return;
258 		break;
259 	}
260 
261 	if (changed & BSS_CHANGED_BEACON_ENABLED) {
262 		if (local->sw_scanning) {
263 			sdata->vif.bss_conf.enable_beacon = false;
264 		} else {
265 			/*
266 			 * Beacon should be enabled, but AP mode must
267 			 * check whether there is a beacon configured.
268 			 */
269 			switch (sdata->vif.type) {
270 			case NL80211_IFTYPE_AP:
271 				sdata->vif.bss_conf.enable_beacon =
272 					!!rcu_dereference(sdata->u.ap.beacon);
273 				break;
274 			case NL80211_IFTYPE_ADHOC:
275 				sdata->vif.bss_conf.enable_beacon =
276 					!!rcu_dereference(sdata->u.ibss.presp);
277 				break;
278 			case NL80211_IFTYPE_MESH_POINT:
279 				sdata->vif.bss_conf.enable_beacon = true;
280 				break;
281 			default:
282 				/* not reached */
283 				WARN_ON(1);
284 				break;
285 			}
286 		}
287 	}
288 
289 	drv_bss_info_changed(local, &sdata->vif,
290 			     &sdata->vif.bss_conf, changed);
291 
292 	/* DEPRECATED */
293 	local->hw.conf.beacon_int = sdata->vif.bss_conf.beacon_int;
294 }
295 
296 u32 ieee80211_reset_erp_info(struct ieee80211_sub_if_data *sdata)
297 {
298 	sdata->vif.bss_conf.use_cts_prot = false;
299 	sdata->vif.bss_conf.use_short_preamble = false;
300 	sdata->vif.bss_conf.use_short_slot = false;
301 	return BSS_CHANGED_ERP_CTS_PROT |
302 	       BSS_CHANGED_ERP_PREAMBLE |
303 	       BSS_CHANGED_ERP_SLOT;
304 }
305 
306 void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
307 				 struct sk_buff *skb)
308 {
309 	struct ieee80211_local *local = hw_to_local(hw);
310 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
311 	int tmp;
312 
313 	skb->dev = local->mdev;
314 	skb->pkt_type = IEEE80211_TX_STATUS_MSG;
315 	skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
316 		       &local->skb_queue : &local->skb_queue_unreliable, skb);
317 	tmp = skb_queue_len(&local->skb_queue) +
318 		skb_queue_len(&local->skb_queue_unreliable);
319 	while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
320 	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
321 		dev_kfree_skb_irq(skb);
322 		tmp--;
323 		I802_DEBUG_INC(local->tx_status_drop);
324 	}
325 	tasklet_schedule(&local->tasklet);
326 }
327 EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
328 
329 static void ieee80211_tasklet_handler(unsigned long data)
330 {
331 	struct ieee80211_local *local = (struct ieee80211_local *) data;
332 	struct sk_buff *skb;
333 	struct ieee80211_rx_status rx_status;
334 	struct ieee80211_ra_tid *ra_tid;
335 
336 	while ((skb = skb_dequeue(&local->skb_queue)) ||
337 	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
338 		switch (skb->pkt_type) {
339 		case IEEE80211_RX_MSG:
340 			/* status is in skb->cb */
341 			memcpy(&rx_status, skb->cb, sizeof(rx_status));
342 			/* Clear skb->pkt_type in order to not confuse kernel
343 			 * netstack. */
344 			skb->pkt_type = 0;
345 			__ieee80211_rx(local_to_hw(local), skb, &rx_status);
346 			break;
347 		case IEEE80211_TX_STATUS_MSG:
348 			skb->pkt_type = 0;
349 			ieee80211_tx_status(local_to_hw(local), skb);
350 			break;
351 		case IEEE80211_DELBA_MSG:
352 			ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
353 			ieee80211_stop_tx_ba_cb(local_to_hw(local),
354 						ra_tid->ra, ra_tid->tid);
355 			dev_kfree_skb(skb);
356 			break;
357 		case IEEE80211_ADDBA_MSG:
358 			ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
359 			ieee80211_start_tx_ba_cb(local_to_hw(local),
360 						 ra_tid->ra, ra_tid->tid);
361 			dev_kfree_skb(skb);
362 			break ;
363 		default:
364 			WARN(1, "mac80211: Packet is of unknown type %d\n",
365 			     skb->pkt_type);
366 			dev_kfree_skb(skb);
367 			break;
368 		}
369 	}
370 }
371 
372 static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
373 					    struct sta_info *sta,
374 					    struct sk_buff *skb)
375 {
376 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
377 
378 	sta->tx_filtered_count++;
379 
380 	/*
381 	 * Clear the TX filter mask for this STA when sending the next
382 	 * packet. If the STA went to power save mode, this will happen
383 	 * when it wakes up for the next time.
384 	 */
385 	set_sta_flags(sta, WLAN_STA_CLEAR_PS_FILT);
386 
387 	/*
388 	 * This code races in the following way:
389 	 *
390 	 *  (1) STA sends frame indicating it will go to sleep and does so
391 	 *  (2) hardware/firmware adds STA to filter list, passes frame up
392 	 *  (3) hardware/firmware processes TX fifo and suppresses a frame
393 	 *  (4) we get TX status before having processed the frame and
394 	 *	knowing that the STA has gone to sleep.
395 	 *
396 	 * This is actually quite unlikely even when both those events are
397 	 * processed from interrupts coming in quickly after one another or
398 	 * even at the same time because we queue both TX status events and
399 	 * RX frames to be processed by a tasklet and process them in the
400 	 * same order that they were received or TX status last. Hence, there
401 	 * is no race as long as the frame RX is processed before the next TX
402 	 * status, which drivers can ensure, see below.
403 	 *
404 	 * Note that this can only happen if the hardware or firmware can
405 	 * actually add STAs to the filter list, if this is done by the
406 	 * driver in response to set_tim() (which will only reduce the race
407 	 * this whole filtering tries to solve, not completely solve it)
408 	 * this situation cannot happen.
409 	 *
410 	 * To completely solve this race drivers need to make sure that they
411 	 *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
412 	 *	functions and
413 	 *  (b) always process RX events before TX status events if ordering
414 	 *      can be unknown, for example with different interrupt status
415 	 *	bits.
416 	 */
417 	if (test_sta_flags(sta, WLAN_STA_PS) &&
418 	    skb_queue_len(&sta->tx_filtered) < STA_MAX_TX_BUFFER) {
419 		skb_queue_tail(&sta->tx_filtered, skb);
420 		return;
421 	}
422 
423 	if (!test_sta_flags(sta, WLAN_STA_PS) &&
424 	    !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
425 		/* Software retry the packet once */
426 		info->flags |= IEEE80211_TX_INTFL_RETRIED;
427 		ieee80211_add_pending_skb(local, skb);
428 		return;
429 	}
430 
431 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
432 	if (net_ratelimit())
433 		printk(KERN_DEBUG "%s: dropped TX filtered frame, "
434 		       "queue_len=%d PS=%d @%lu\n",
435 		       wiphy_name(local->hw.wiphy),
436 		       skb_queue_len(&sta->tx_filtered),
437 		       !!test_sta_flags(sta, WLAN_STA_PS), jiffies);
438 #endif
439 	dev_kfree_skb(skb);
440 }
441 
442 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
443 {
444 	struct sk_buff *skb2;
445 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
446 	struct ieee80211_local *local = hw_to_local(hw);
447 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
448 	u16 frag, type;
449 	__le16 fc;
450 	struct ieee80211_supported_band *sband;
451 	struct ieee80211_tx_status_rtap_hdr *rthdr;
452 	struct ieee80211_sub_if_data *sdata;
453 	struct net_device *prev_dev = NULL;
454 	struct sta_info *sta;
455 	int retry_count = -1, i;
456 
457 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
458 		/* the HW cannot have attempted that rate */
459 		if (i >= hw->max_rates) {
460 			info->status.rates[i].idx = -1;
461 			info->status.rates[i].count = 0;
462 		}
463 
464 		retry_count += info->status.rates[i].count;
465 	}
466 	if (retry_count < 0)
467 		retry_count = 0;
468 
469 	rcu_read_lock();
470 
471 	sband = local->hw.wiphy->bands[info->band];
472 
473 	sta = sta_info_get(local, hdr->addr1);
474 
475 	if (sta) {
476 		if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
477 		    test_sta_flags(sta, WLAN_STA_PS)) {
478 			/*
479 			 * The STA is in power save mode, so assume
480 			 * that this TX packet failed because of that.
481 			 */
482 			ieee80211_handle_filtered_frame(local, sta, skb);
483 			rcu_read_unlock();
484 			return;
485 		}
486 
487 		fc = hdr->frame_control;
488 
489 		if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
490 		    (ieee80211_is_data_qos(fc))) {
491 			u16 tid, ssn;
492 			u8 *qc;
493 
494 			qc = ieee80211_get_qos_ctl(hdr);
495 			tid = qc[0] & 0xf;
496 			ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
497 						& IEEE80211_SCTL_SEQ);
498 			ieee80211_send_bar(sta->sdata, hdr->addr1,
499 					   tid, ssn);
500 		}
501 
502 		if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
503 			ieee80211_handle_filtered_frame(local, sta, skb);
504 			rcu_read_unlock();
505 			return;
506 		} else {
507 			if (!(info->flags & IEEE80211_TX_STAT_ACK))
508 				sta->tx_retry_failed++;
509 			sta->tx_retry_count += retry_count;
510 		}
511 
512 		rate_control_tx_status(local, sband, sta, skb);
513 	}
514 
515 	rcu_read_unlock();
516 
517 	ieee80211_led_tx(local, 0);
518 
519 	/* SNMP counters
520 	 * Fragments are passed to low-level drivers as separate skbs, so these
521 	 * are actually fragments, not frames. Update frame counters only for
522 	 * the first fragment of the frame. */
523 
524 	frag = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG;
525 	type = le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_FTYPE;
526 
527 	if (info->flags & IEEE80211_TX_STAT_ACK) {
528 		if (frag == 0) {
529 			local->dot11TransmittedFrameCount++;
530 			if (is_multicast_ether_addr(hdr->addr1))
531 				local->dot11MulticastTransmittedFrameCount++;
532 			if (retry_count > 0)
533 				local->dot11RetryCount++;
534 			if (retry_count > 1)
535 				local->dot11MultipleRetryCount++;
536 		}
537 
538 		/* This counter shall be incremented for an acknowledged MPDU
539 		 * with an individual address in the address 1 field or an MPDU
540 		 * with a multicast address in the address 1 field of type Data
541 		 * or Management. */
542 		if (!is_multicast_ether_addr(hdr->addr1) ||
543 		    type == IEEE80211_FTYPE_DATA ||
544 		    type == IEEE80211_FTYPE_MGMT)
545 			local->dot11TransmittedFragmentCount++;
546 	} else {
547 		if (frag == 0)
548 			local->dot11FailedCount++;
549 	}
550 
551 	/* this was a transmitted frame, but now we want to reuse it */
552 	skb_orphan(skb);
553 
554 	/*
555 	 * This is a bit racy but we can avoid a lot of work
556 	 * with this test...
557 	 */
558 	if (!local->monitors && !local->cooked_mntrs) {
559 		dev_kfree_skb(skb);
560 		return;
561 	}
562 
563 	/* send frame to monitor interfaces now */
564 
565 	if (skb_headroom(skb) < sizeof(*rthdr)) {
566 		printk(KERN_ERR "ieee80211_tx_status: headroom too small\n");
567 		dev_kfree_skb(skb);
568 		return;
569 	}
570 
571 	rthdr = (struct ieee80211_tx_status_rtap_hdr *)
572 				skb_push(skb, sizeof(*rthdr));
573 
574 	memset(rthdr, 0, sizeof(*rthdr));
575 	rthdr->hdr.it_len = cpu_to_le16(sizeof(*rthdr));
576 	rthdr->hdr.it_present =
577 		cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
578 			    (1 << IEEE80211_RADIOTAP_DATA_RETRIES) |
579 			    (1 << IEEE80211_RADIOTAP_RATE));
580 
581 	if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
582 	    !is_multicast_ether_addr(hdr->addr1))
583 		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_FAIL);
584 
585 	/*
586 	 * XXX: Once radiotap gets the bitmap reset thing the vendor
587 	 *	extensions proposal contains, we can actually report
588 	 *	the whole set of tries we did.
589 	 */
590 	if ((info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
591 	    (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
592 		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_CTS);
593 	else if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
594 		rthdr->tx_flags |= cpu_to_le16(IEEE80211_RADIOTAP_F_TX_RTS);
595 	if (info->status.rates[0].idx >= 0 &&
596 	    !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS))
597 		rthdr->rate = sband->bitrates[
598 				info->status.rates[0].idx].bitrate / 5;
599 
600 	/* for now report the total retry_count */
601 	rthdr->data_retries = retry_count;
602 
603 	/* XXX: is this sufficient for BPF? */
604 	skb_set_mac_header(skb, 0);
605 	skb->ip_summed = CHECKSUM_UNNECESSARY;
606 	skb->pkt_type = PACKET_OTHERHOST;
607 	skb->protocol = htons(ETH_P_802_2);
608 	memset(skb->cb, 0, sizeof(skb->cb));
609 
610 	rcu_read_lock();
611 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
612 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
613 			if (!netif_running(sdata->dev))
614 				continue;
615 
616 			if (prev_dev) {
617 				skb2 = skb_clone(skb, GFP_ATOMIC);
618 				if (skb2) {
619 					skb2->dev = prev_dev;
620 					netif_rx(skb2);
621 				}
622 			}
623 
624 			prev_dev = sdata->dev;
625 		}
626 	}
627 	if (prev_dev) {
628 		skb->dev = prev_dev;
629 		netif_rx(skb);
630 		skb = NULL;
631 	}
632 	rcu_read_unlock();
633 	dev_kfree_skb(skb);
634 }
635 EXPORT_SYMBOL(ieee80211_tx_status);
636 
637 static void ieee80211_restart_work(struct work_struct *work)
638 {
639 	struct ieee80211_local *local =
640 		container_of(work, struct ieee80211_local, restart_work);
641 
642 	rtnl_lock();
643 	ieee80211_reconfig(local);
644 	rtnl_unlock();
645 }
646 
647 void ieee80211_restart_hw(struct ieee80211_hw *hw)
648 {
649 	struct ieee80211_local *local = hw_to_local(hw);
650 
651 	/* use this reason, __ieee80211_resume will unblock it */
652 	ieee80211_stop_queues_by_reason(hw,
653 		IEEE80211_QUEUE_STOP_REASON_SUSPEND);
654 
655 	schedule_work(&local->restart_work);
656 }
657 EXPORT_SYMBOL(ieee80211_restart_hw);
658 
659 struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
660 					const struct ieee80211_ops *ops)
661 {
662 	struct ieee80211_local *local;
663 	int priv_size, i;
664 	struct wiphy *wiphy;
665 
666 	/* Ensure 32-byte alignment of our private data and hw private data.
667 	 * We use the wiphy priv data for both our ieee80211_local and for
668 	 * the driver's private data
669 	 *
670 	 * In memory it'll be like this:
671 	 *
672 	 * +-------------------------+
673 	 * | struct wiphy	    |
674 	 * +-------------------------+
675 	 * | struct ieee80211_local  |
676 	 * +-------------------------+
677 	 * | driver's private data   |
678 	 * +-------------------------+
679 	 *
680 	 */
681 	priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;
682 
683 	wiphy = wiphy_new(&mac80211_config_ops, priv_size);
684 
685 	if (!wiphy)
686 		return NULL;
687 
688 	wiphy->privid = mac80211_wiphy_privid;
689 
690 	/* Yes, putting cfg80211_bss into ieee80211_bss is a hack */
691 	wiphy->bss_priv_size = sizeof(struct ieee80211_bss) -
692 			       sizeof(struct cfg80211_bss);
693 
694 	local = wiphy_priv(wiphy);
695 
696 	local->hw.wiphy = wiphy;
697 
698 	local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);
699 
700 	BUG_ON(!ops->tx);
701 	BUG_ON(!ops->start);
702 	BUG_ON(!ops->stop);
703 	BUG_ON(!ops->config);
704 	BUG_ON(!ops->add_interface);
705 	BUG_ON(!ops->remove_interface);
706 	BUG_ON(!ops->configure_filter);
707 	local->ops = ops;
708 
709 	/* set up some defaults */
710 	local->hw.queues = 1;
711 	local->hw.max_rates = 1;
712 	local->hw.conf.long_frame_max_tx_count = wiphy->retry_long;
713 	local->hw.conf.short_frame_max_tx_count = wiphy->retry_short;
714 	local->hw.conf.radio_enabled = true;
715 	local->user_power_level = -1;
716 
717 	INIT_LIST_HEAD(&local->interfaces);
718 	mutex_init(&local->iflist_mtx);
719 	mutex_init(&local->scan_mtx);
720 
721 	spin_lock_init(&local->key_lock);
722 
723 	spin_lock_init(&local->queue_stop_reason_lock);
724 
725 	INIT_DELAYED_WORK(&local->scan_work, ieee80211_scan_work);
726 
727 	INIT_WORK(&local->restart_work, ieee80211_restart_work);
728 
729 	INIT_WORK(&local->dynamic_ps_enable_work,
730 		  ieee80211_dynamic_ps_enable_work);
731 	INIT_WORK(&local->dynamic_ps_disable_work,
732 		  ieee80211_dynamic_ps_disable_work);
733 	setup_timer(&local->dynamic_ps_timer,
734 		    ieee80211_dynamic_ps_timer, (unsigned long) local);
735 
736 	sta_info_init(local);
737 
738 	for (i = 0; i < IEEE80211_MAX_QUEUES; i++)
739 		skb_queue_head_init(&local->pending[i]);
740 	tasklet_init(&local->tx_pending_tasklet, ieee80211_tx_pending,
741 		     (unsigned long)local);
742 	tasklet_disable(&local->tx_pending_tasklet);
743 
744 	tasklet_init(&local->tasklet,
745 		     ieee80211_tasklet_handler,
746 		     (unsigned long) local);
747 	tasklet_disable(&local->tasklet);
748 
749 	skb_queue_head_init(&local->skb_queue);
750 	skb_queue_head_init(&local->skb_queue_unreliable);
751 
752 	spin_lock_init(&local->ampdu_lock);
753 
754 	return local_to_hw(local);
755 }
756 EXPORT_SYMBOL(ieee80211_alloc_hw);
757 
758 static const struct net_device_ops ieee80211_master_ops = {
759 	.ndo_start_xmit = ieee80211_master_start_xmit,
760 	.ndo_open = ieee80211_master_open,
761 	.ndo_stop = ieee80211_master_stop,
762 	.ndo_set_multicast_list = ieee80211_master_set_multicast_list,
763 	.ndo_select_queue = ieee80211_select_queue,
764 };
765 
766 static void ieee80211_master_setup(struct net_device *mdev)
767 {
768 	mdev->type = ARPHRD_IEEE80211;
769 	mdev->netdev_ops = &ieee80211_master_ops;
770 	mdev->header_ops = &ieee80211_header_ops;
771 	mdev->tx_queue_len = 1000;
772 	mdev->addr_len = ETH_ALEN;
773 }
774 
775 int ieee80211_register_hw(struct ieee80211_hw *hw)
776 {
777 	struct ieee80211_local *local = hw_to_local(hw);
778 	int result;
779 	enum ieee80211_band band;
780 	struct net_device *mdev;
781 	struct ieee80211_master_priv *mpriv;
782 	int channels, i, j, max_bitrates;
783 	bool supp_ht;
784 	static const u32 cipher_suites[] = {
785 		WLAN_CIPHER_SUITE_WEP40,
786 		WLAN_CIPHER_SUITE_WEP104,
787 		WLAN_CIPHER_SUITE_TKIP,
788 		WLAN_CIPHER_SUITE_CCMP,
789 
790 		/* keep last -- depends on hw flags! */
791 		WLAN_CIPHER_SUITE_AES_CMAC
792 	};
793 
794 	/*
795 	 * generic code guarantees at least one band,
796 	 * set this very early because much code assumes
797 	 * that hw.conf.channel is assigned
798 	 */
799 	channels = 0;
800 	max_bitrates = 0;
801 	supp_ht = false;
802 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
803 		struct ieee80211_supported_band *sband;
804 
805 		sband = local->hw.wiphy->bands[band];
806 		if (!sband)
807 			continue;
808 		if (!local->oper_channel) {
809 			/* init channel we're on */
810 			local->hw.conf.channel =
811 			local->oper_channel = &sband->channels[0];
812 			local->hw.conf.channel_type = NL80211_CHAN_NO_HT;
813 		}
814 		channels += sband->n_channels;
815 
816 		if (max_bitrates < sband->n_bitrates)
817 			max_bitrates = sband->n_bitrates;
818 		supp_ht = supp_ht || sband->ht_cap.ht_supported;
819 	}
820 
821 	local->int_scan_req.n_channels = channels;
822 	local->int_scan_req.channels = kzalloc(sizeof(void *) * channels, GFP_KERNEL);
823 	if (!local->int_scan_req.channels)
824 		return -ENOMEM;
825 
826 	/* if low-level driver supports AP, we also support VLAN */
827 	if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_AP))
828 		local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_AP_VLAN);
829 
830 	/* mac80211 always supports monitor */
831 	local->hw.wiphy->interface_modes |= BIT(NL80211_IFTYPE_MONITOR);
832 
833 	if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
834 		local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
835 	else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
836 		local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_UNSPEC;
837 
838 	/*
839 	 * Calculate scan IE length -- we need this to alloc
840 	 * memory and to subtract from the driver limit. It
841 	 * includes the (extended) supported rates and HT
842 	 * information -- SSID is the driver's responsibility.
843 	 */
844 	local->scan_ies_len = 4 + max_bitrates; /* (ext) supp rates */
845 	if (supp_ht)
846 		local->scan_ies_len += 2 + sizeof(struct ieee80211_ht_cap);
847 
848 	if (!local->ops->hw_scan) {
849 		/* For hw_scan, driver needs to set these up. */
850 		local->hw.wiphy->max_scan_ssids = 4;
851 		local->hw.wiphy->max_scan_ie_len = IEEE80211_MAX_DATA_LEN;
852 	}
853 
854 	/*
855 	 * If the driver supports any scan IEs, then assume the
856 	 * limit includes the IEs mac80211 will add, otherwise
857 	 * leave it at zero and let the driver sort it out; we
858 	 * still pass our IEs to the driver but userspace will
859 	 * not be allowed to in that case.
860 	 */
861 	if (local->hw.wiphy->max_scan_ie_len)
862 		local->hw.wiphy->max_scan_ie_len -= local->scan_ies_len;
863 
864 	local->hw.wiphy->cipher_suites = cipher_suites;
865 	local->hw.wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);
866 	if (!(local->hw.flags & IEEE80211_HW_MFP_CAPABLE))
867 		local->hw.wiphy->n_cipher_suites--;
868 
869 	result = wiphy_register(local->hw.wiphy);
870 	if (result < 0)
871 		goto fail_wiphy_register;
872 
873 	/*
874 	 * We use the number of queues for feature tests (QoS, HT) internally
875 	 * so restrict them appropriately.
876 	 */
877 	if (hw->queues > IEEE80211_MAX_QUEUES)
878 		hw->queues = IEEE80211_MAX_QUEUES;
879 
880 	mdev = alloc_netdev_mq(sizeof(struct ieee80211_master_priv),
881 			       "wmaster%d", ieee80211_master_setup,
882 			       hw->queues);
883 	if (!mdev)
884 		goto fail_mdev_alloc;
885 
886 	mpriv = netdev_priv(mdev);
887 	mpriv->local = local;
888 	local->mdev = mdev;
889 
890 	local->hw.workqueue =
891 		create_singlethread_workqueue(wiphy_name(local->hw.wiphy));
892 	if (!local->hw.workqueue) {
893 		result = -ENOMEM;
894 		goto fail_workqueue;
895 	}
896 
897 	/*
898 	 * The hardware needs headroom for sending the frame,
899 	 * and we need some headroom for passing the frame to monitor
900 	 * interfaces, but never both at the same time.
901 	 */
902 	local->tx_headroom = max_t(unsigned int , local->hw.extra_tx_headroom,
903 				   sizeof(struct ieee80211_tx_status_rtap_hdr));
904 
905 	debugfs_hw_add(local);
906 
907 	if (local->hw.max_listen_interval == 0)
908 		local->hw.max_listen_interval = 1;
909 
910 	local->hw.conf.listen_interval = local->hw.max_listen_interval;
911 
912 	result = sta_info_start(local);
913 	if (result < 0)
914 		goto fail_sta_info;
915 
916 	result = ieee80211_wep_init(local);
917 	if (result < 0) {
918 		printk(KERN_DEBUG "%s: Failed to initialize wep: %d\n",
919 		       wiphy_name(local->hw.wiphy), result);
920 		goto fail_wep;
921 	}
922 
923 	rtnl_lock();
924 	result = dev_alloc_name(local->mdev, local->mdev->name);
925 	if (result < 0)
926 		goto fail_dev;
927 
928 	memcpy(local->mdev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
929 	SET_NETDEV_DEV(local->mdev, wiphy_dev(local->hw.wiphy));
930 	local->mdev->features |= NETIF_F_NETNS_LOCAL;
931 
932 	result = register_netdevice(local->mdev);
933 	if (result < 0)
934 		goto fail_dev;
935 
936 	result = ieee80211_init_rate_ctrl_alg(local,
937 					      hw->rate_control_algorithm);
938 	if (result < 0) {
939 		printk(KERN_DEBUG "%s: Failed to initialize rate control "
940 		       "algorithm\n", wiphy_name(local->hw.wiphy));
941 		goto fail_rate;
942 	}
943 
944 	/* add one default STA interface if supported */
945 	if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_STATION)) {
946 		result = ieee80211_if_add(local, "wlan%d", NULL,
947 					  NL80211_IFTYPE_STATION, NULL);
948 		if (result)
949 			printk(KERN_WARNING "%s: Failed to add default virtual iface\n",
950 			       wiphy_name(local->hw.wiphy));
951 	}
952 
953 	rtnl_unlock();
954 
955 	ieee80211_led_init(local);
956 
957 	/* alloc internal scan request */
958 	i = 0;
959 	local->int_scan_req.ssids = &local->scan_ssid;
960 	local->int_scan_req.n_ssids = 1;
961 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
962 		if (!hw->wiphy->bands[band])
963 			continue;
964 		for (j = 0; j < hw->wiphy->bands[band]->n_channels; j++) {
965 			local->int_scan_req.channels[i] =
966 				&hw->wiphy->bands[band]->channels[j];
967 			i++;
968 		}
969 	}
970 
971 	local->network_latency_notifier.notifier_call =
972 		ieee80211_max_network_latency;
973 	result = pm_qos_add_notifier(PM_QOS_NETWORK_LATENCY,
974 				     &local->network_latency_notifier);
975 
976 	if (result) {
977 		rtnl_lock();
978 		goto fail_pm_qos;
979 	}
980 
981 	return 0;
982 
983  fail_pm_qos:
984 	ieee80211_led_exit(local);
985 	ieee80211_remove_interfaces(local);
986  fail_rate:
987 	unregister_netdevice(local->mdev);
988 	local->mdev = NULL;
989  fail_dev:
990 	rtnl_unlock();
991 	ieee80211_wep_free(local);
992  fail_wep:
993 	sta_info_stop(local);
994  fail_sta_info:
995 	debugfs_hw_del(local);
996 	destroy_workqueue(local->hw.workqueue);
997  fail_workqueue:
998 	if (local->mdev)
999 		free_netdev(local->mdev);
1000  fail_mdev_alloc:
1001 	wiphy_unregister(local->hw.wiphy);
1002  fail_wiphy_register:
1003 	kfree(local->int_scan_req.channels);
1004 	return result;
1005 }
1006 EXPORT_SYMBOL(ieee80211_register_hw);
1007 
1008 void ieee80211_unregister_hw(struct ieee80211_hw *hw)
1009 {
1010 	struct ieee80211_local *local = hw_to_local(hw);
1011 
1012 	tasklet_kill(&local->tx_pending_tasklet);
1013 	tasklet_kill(&local->tasklet);
1014 
1015 	pm_qos_remove_notifier(PM_QOS_NETWORK_LATENCY,
1016 			       &local->network_latency_notifier);
1017 
1018 	rtnl_lock();
1019 
1020 	/*
1021 	 * At this point, interface list manipulations are fine
1022 	 * because the driver cannot be handing us frames any
1023 	 * more and the tasklet is killed.
1024 	 */
1025 
1026 	/* First, we remove all virtual interfaces. */
1027 	ieee80211_remove_interfaces(local);
1028 
1029 	/* then, finally, remove the master interface */
1030 	unregister_netdevice(local->mdev);
1031 
1032 	rtnl_unlock();
1033 
1034 	ieee80211_clear_tx_pending(local);
1035 	sta_info_stop(local);
1036 	rate_control_deinitialize(local);
1037 	debugfs_hw_del(local);
1038 
1039 	if (skb_queue_len(&local->skb_queue)
1040 			|| skb_queue_len(&local->skb_queue_unreliable))
1041 		printk(KERN_WARNING "%s: skb_queue not empty\n",
1042 		       wiphy_name(local->hw.wiphy));
1043 	skb_queue_purge(&local->skb_queue);
1044 	skb_queue_purge(&local->skb_queue_unreliable);
1045 
1046 	destroy_workqueue(local->hw.workqueue);
1047 	wiphy_unregister(local->hw.wiphy);
1048 	ieee80211_wep_free(local);
1049 	ieee80211_led_exit(local);
1050 	free_netdev(local->mdev);
1051 	kfree(local->int_scan_req.channels);
1052 }
1053 EXPORT_SYMBOL(ieee80211_unregister_hw);
1054 
1055 void ieee80211_free_hw(struct ieee80211_hw *hw)
1056 {
1057 	struct ieee80211_local *local = hw_to_local(hw);
1058 
1059 	mutex_destroy(&local->iflist_mtx);
1060 	mutex_destroy(&local->scan_mtx);
1061 
1062 	wiphy_free(local->hw.wiphy);
1063 }
1064 EXPORT_SYMBOL(ieee80211_free_hw);
1065 
1066 static int __init ieee80211_init(void)
1067 {
1068 	struct sk_buff *skb;
1069 	int ret;
1070 
1071 	BUILD_BUG_ON(sizeof(struct ieee80211_tx_info) > sizeof(skb->cb));
1072 	BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, driver_data) +
1073 		     IEEE80211_TX_INFO_DRIVER_DATA_SIZE > sizeof(skb->cb));
1074 
1075 	ret = rc80211_minstrel_init();
1076 	if (ret)
1077 		return ret;
1078 
1079 	ret = rc80211_pid_init();
1080 	if (ret)
1081 		return ret;
1082 
1083 	ieee80211_debugfs_netdev_init();
1084 
1085 	return 0;
1086 }
1087 
1088 static void __exit ieee80211_exit(void)
1089 {
1090 	rc80211_pid_exit();
1091 	rc80211_minstrel_exit();
1092 
1093 	/*
1094 	 * For key todo, it'll be empty by now but the work
1095 	 * might still be scheduled.
1096 	 */
1097 	flush_scheduled_work();
1098 
1099 	if (mesh_allocated)
1100 		ieee80211s_stop();
1101 
1102 	ieee80211_debugfs_netdev_exit();
1103 }
1104 
1105 
1106 subsys_initcall(ieee80211_init);
1107 module_exit(ieee80211_exit);
1108 
1109 MODULE_DESCRIPTION("IEEE 802.11 subsystem");
1110 MODULE_LICENSE("GPL");
1111