xref: /openbmc/linux/net/mac80211/tx.c (revision 78700c0a)
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  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  *
13  * Transmit and frame generation functions.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/skbuff.h>
19 #include <linux/etherdevice.h>
20 #include <linux/bitmap.h>
21 #include <linux/rcupdate.h>
22 #include <linux/export.h>
23 #include <net/net_namespace.h>
24 #include <net/ieee80211_radiotap.h>
25 #include <net/cfg80211.h>
26 #include <net/mac80211.h>
27 #include <asm/unaligned.h>
28 
29 #include "ieee80211_i.h"
30 #include "driver-ops.h"
31 #include "led.h"
32 #include "mesh.h"
33 #include "wep.h"
34 #include "wpa.h"
35 #include "wme.h"
36 #include "rate.h"
37 
38 /* misc utils */
39 
40 static inline void ieee80211_tx_stats(struct net_device *dev, u32 len)
41 {
42 	struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
43 
44 	u64_stats_update_begin(&tstats->syncp);
45 	tstats->tx_packets++;
46 	tstats->tx_bytes += len;
47 	u64_stats_update_end(&tstats->syncp);
48 }
49 
50 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx,
51 				 struct sk_buff *skb, int group_addr,
52 				 int next_frag_len)
53 {
54 	int rate, mrate, erp, dur, i, shift = 0;
55 	struct ieee80211_rate *txrate;
56 	struct ieee80211_local *local = tx->local;
57 	struct ieee80211_supported_band *sband;
58 	struct ieee80211_hdr *hdr;
59 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
60 	struct ieee80211_chanctx_conf *chanctx_conf;
61 	u32 rate_flags = 0;
62 
63 	rcu_read_lock();
64 	chanctx_conf = rcu_dereference(tx->sdata->vif.chanctx_conf);
65 	if (chanctx_conf) {
66 		shift = ieee80211_chandef_get_shift(&chanctx_conf->def);
67 		rate_flags = ieee80211_chandef_rate_flags(&chanctx_conf->def);
68 	}
69 	rcu_read_unlock();
70 
71 	/* assume HW handles this */
72 	if (tx->rate.flags & (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))
73 		return 0;
74 
75 	/* uh huh? */
76 	if (WARN_ON_ONCE(tx->rate.idx < 0))
77 		return 0;
78 
79 	sband = local->hw.wiphy->bands[info->band];
80 	txrate = &sband->bitrates[tx->rate.idx];
81 
82 	erp = txrate->flags & IEEE80211_RATE_ERP_G;
83 
84 	/*
85 	 * data and mgmt (except PS Poll):
86 	 * - during CFP: 32768
87 	 * - during contention period:
88 	 *   if addr1 is group address: 0
89 	 *   if more fragments = 0 and addr1 is individual address: time to
90 	 *      transmit one ACK plus SIFS
91 	 *   if more fragments = 1 and addr1 is individual address: time to
92 	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
93 	 *
94 	 * IEEE 802.11, 9.6:
95 	 * - control response frame (CTS or ACK) shall be transmitted using the
96 	 *   same rate as the immediately previous frame in the frame exchange
97 	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
98 	 *   at the highest possible rate belonging to the PHY rates in the
99 	 *   BSSBasicRateSet
100 	 */
101 	hdr = (struct ieee80211_hdr *)skb->data;
102 	if (ieee80211_is_ctl(hdr->frame_control)) {
103 		/* TODO: These control frames are not currently sent by
104 		 * mac80211, but should they be implemented, this function
105 		 * needs to be updated to support duration field calculation.
106 		 *
107 		 * RTS: time needed to transmit pending data/mgmt frame plus
108 		 *    one CTS frame plus one ACK frame plus 3 x SIFS
109 		 * CTS: duration of immediately previous RTS minus time
110 		 *    required to transmit CTS and its SIFS
111 		 * ACK: 0 if immediately previous directed data/mgmt had
112 		 *    more=0, with more=1 duration in ACK frame is duration
113 		 *    from previous frame minus time needed to transmit ACK
114 		 *    and its SIFS
115 		 * PS Poll: BIT(15) | BIT(14) | aid
116 		 */
117 		return 0;
118 	}
119 
120 	/* data/mgmt */
121 	if (0 /* FIX: data/mgmt during CFP */)
122 		return cpu_to_le16(32768);
123 
124 	if (group_addr) /* Group address as the destination - no ACK */
125 		return 0;
126 
127 	/* Individual destination address:
128 	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
129 	 * CTS and ACK frames shall be transmitted using the highest rate in
130 	 * basic rate set that is less than or equal to the rate of the
131 	 * immediately previous frame and that is using the same modulation
132 	 * (CCK or OFDM). If no basic rate set matches with these requirements,
133 	 * the highest mandatory rate of the PHY that is less than or equal to
134 	 * the rate of the previous frame is used.
135 	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
136 	 */
137 	rate = -1;
138 	/* use lowest available if everything fails */
139 	mrate = sband->bitrates[0].bitrate;
140 	for (i = 0; i < sband->n_bitrates; i++) {
141 		struct ieee80211_rate *r = &sband->bitrates[i];
142 
143 		if (r->bitrate > txrate->bitrate)
144 			break;
145 
146 		if ((rate_flags & r->flags) != rate_flags)
147 			continue;
148 
149 		if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
150 			rate = DIV_ROUND_UP(r->bitrate, 1 << shift);
151 
152 		switch (sband->band) {
153 		case NL80211_BAND_2GHZ: {
154 			u32 flag;
155 			if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
156 				flag = IEEE80211_RATE_MANDATORY_G;
157 			else
158 				flag = IEEE80211_RATE_MANDATORY_B;
159 			if (r->flags & flag)
160 				mrate = r->bitrate;
161 			break;
162 		}
163 		case NL80211_BAND_5GHZ:
164 			if (r->flags & IEEE80211_RATE_MANDATORY_A)
165 				mrate = r->bitrate;
166 			break;
167 		case NL80211_BAND_60GHZ:
168 			/* TODO, for now fall through */
169 		case NUM_NL80211_BANDS:
170 			WARN_ON(1);
171 			break;
172 		}
173 	}
174 	if (rate == -1) {
175 		/* No matching basic rate found; use highest suitable mandatory
176 		 * PHY rate */
177 		rate = DIV_ROUND_UP(mrate, 1 << shift);
178 	}
179 
180 	/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
181 	if (ieee80211_is_data_qos(hdr->frame_control) &&
182 	    *(ieee80211_get_qos_ctl(hdr)) & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
183 		dur = 0;
184 	else
185 		/* Time needed to transmit ACK
186 		 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
187 		 * to closest integer */
188 		dur = ieee80211_frame_duration(sband->band, 10, rate, erp,
189 				tx->sdata->vif.bss_conf.use_short_preamble,
190 				shift);
191 
192 	if (next_frag_len) {
193 		/* Frame is fragmented: duration increases with time needed to
194 		 * transmit next fragment plus ACK and 2 x SIFS. */
195 		dur *= 2; /* ACK + SIFS */
196 		/* next fragment */
197 		dur += ieee80211_frame_duration(sband->band, next_frag_len,
198 				txrate->bitrate, erp,
199 				tx->sdata->vif.bss_conf.use_short_preamble,
200 				shift);
201 	}
202 
203 	return cpu_to_le16(dur);
204 }
205 
206 /* tx handlers */
207 static ieee80211_tx_result debug_noinline
208 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
209 {
210 	struct ieee80211_local *local = tx->local;
211 	struct ieee80211_if_managed *ifmgd;
212 
213 	/* driver doesn't support power save */
214 	if (!ieee80211_hw_check(&local->hw, SUPPORTS_PS))
215 		return TX_CONTINUE;
216 
217 	/* hardware does dynamic power save */
218 	if (ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
219 		return TX_CONTINUE;
220 
221 	/* dynamic power save disabled */
222 	if (local->hw.conf.dynamic_ps_timeout <= 0)
223 		return TX_CONTINUE;
224 
225 	/* we are scanning, don't enable power save */
226 	if (local->scanning)
227 		return TX_CONTINUE;
228 
229 	if (!local->ps_sdata)
230 		return TX_CONTINUE;
231 
232 	/* No point if we're going to suspend */
233 	if (local->quiescing)
234 		return TX_CONTINUE;
235 
236 	/* dynamic ps is supported only in managed mode */
237 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
238 		return TX_CONTINUE;
239 
240 	ifmgd = &tx->sdata->u.mgd;
241 
242 	/*
243 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
244 	 * u-apsd enabled and the frame is in voip class. This effectively
245 	 * means that even if all access categories have u-apsd enabled, in
246 	 * practise u-apsd is only used with the voip ac. This is a
247 	 * workaround for the case when received voip class packets do not
248 	 * have correct qos tag for some reason, due the network or the
249 	 * peer application.
250 	 *
251 	 * Note: ifmgd->uapsd_queues access is racy here. If the value is
252 	 * changed via debugfs, user needs to reassociate manually to have
253 	 * everything in sync.
254 	 */
255 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
256 	    (ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
257 	    skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
258 		return TX_CONTINUE;
259 
260 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
261 		ieee80211_stop_queues_by_reason(&local->hw,
262 						IEEE80211_MAX_QUEUE_MAP,
263 						IEEE80211_QUEUE_STOP_REASON_PS,
264 						false);
265 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
266 		ieee80211_queue_work(&local->hw,
267 				     &local->dynamic_ps_disable_work);
268 	}
269 
270 	/* Don't restart the timer if we're not disassociated */
271 	if (!ifmgd->associated)
272 		return TX_CONTINUE;
273 
274 	mod_timer(&local->dynamic_ps_timer, jiffies +
275 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
276 
277 	return TX_CONTINUE;
278 }
279 
280 static ieee80211_tx_result debug_noinline
281 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
282 {
283 
284 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
285 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
286 	bool assoc = false;
287 
288 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
289 		return TX_CONTINUE;
290 
291 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
292 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
293 	    !ieee80211_is_probe_req(hdr->frame_control) &&
294 	    !ieee80211_is_nullfunc(hdr->frame_control))
295 		/*
296 		 * When software scanning only nullfunc frames (to notify
297 		 * the sleep state to the AP) and probe requests (for the
298 		 * active scan) are allowed, all other frames should not be
299 		 * sent and we should not get here, but if we do
300 		 * nonetheless, drop them to avoid sending them
301 		 * off-channel. See the link below and
302 		 * ieee80211_start_scan() for more.
303 		 *
304 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
305 		 */
306 		return TX_DROP;
307 
308 	if (tx->sdata->vif.type == NL80211_IFTYPE_OCB)
309 		return TX_CONTINUE;
310 
311 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
312 		return TX_CONTINUE;
313 
314 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
315 		return TX_CONTINUE;
316 
317 	if (tx->sta)
318 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
319 
320 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
321 		if (unlikely(!assoc &&
322 			     ieee80211_is_data(hdr->frame_control))) {
323 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
324 			sdata_info(tx->sdata,
325 				   "dropped data frame to not associated station %pM\n",
326 				   hdr->addr1);
327 #endif
328 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
329 			return TX_DROP;
330 		}
331 	} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
332 			    ieee80211_is_data(hdr->frame_control) &&
333 			    !atomic_read(&tx->sdata->u.ap.num_mcast_sta))) {
334 		/*
335 		 * No associated STAs - no need to send multicast
336 		 * frames.
337 		 */
338 		return TX_DROP;
339 	}
340 
341 	return TX_CONTINUE;
342 }
343 
344 /* This function is called whenever the AP is about to exceed the maximum limit
345  * of buffered frames for power saving STAs. This situation should not really
346  * happen often during normal operation, so dropping the oldest buffered packet
347  * from each queue should be OK to make some room for new frames. */
348 static void purge_old_ps_buffers(struct ieee80211_local *local)
349 {
350 	int total = 0, purged = 0;
351 	struct sk_buff *skb;
352 	struct ieee80211_sub_if_data *sdata;
353 	struct sta_info *sta;
354 
355 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
356 		struct ps_data *ps;
357 
358 		if (sdata->vif.type == NL80211_IFTYPE_AP)
359 			ps = &sdata->u.ap.ps;
360 		else if (ieee80211_vif_is_mesh(&sdata->vif))
361 			ps = &sdata->u.mesh.ps;
362 		else
363 			continue;
364 
365 		skb = skb_dequeue(&ps->bc_buf);
366 		if (skb) {
367 			purged++;
368 			dev_kfree_skb(skb);
369 		}
370 		total += skb_queue_len(&ps->bc_buf);
371 	}
372 
373 	/*
374 	 * Drop one frame from each station from the lowest-priority
375 	 * AC that has frames at all.
376 	 */
377 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
378 		int ac;
379 
380 		for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
381 			skb = skb_dequeue(&sta->ps_tx_buf[ac]);
382 			total += skb_queue_len(&sta->ps_tx_buf[ac]);
383 			if (skb) {
384 				purged++;
385 				ieee80211_free_txskb(&local->hw, skb);
386 				break;
387 			}
388 		}
389 	}
390 
391 	local->total_ps_buffered = total;
392 	ps_dbg_hw(&local->hw, "PS buffers full - purged %d frames\n", purged);
393 }
394 
395 static ieee80211_tx_result
396 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
397 {
398 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
399 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
400 	struct ps_data *ps;
401 
402 	/*
403 	 * broadcast/multicast frame
404 	 *
405 	 * If any of the associated/peer stations is in power save mode,
406 	 * the frame is buffered to be sent after DTIM beacon frame.
407 	 * This is done either by the hardware or us.
408 	 */
409 
410 	/* powersaving STAs currently only in AP/VLAN/mesh mode */
411 	if (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
412 	    tx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
413 		if (!tx->sdata->bss)
414 			return TX_CONTINUE;
415 
416 		ps = &tx->sdata->bss->ps;
417 	} else if (ieee80211_vif_is_mesh(&tx->sdata->vif)) {
418 		ps = &tx->sdata->u.mesh.ps;
419 	} else {
420 		return TX_CONTINUE;
421 	}
422 
423 
424 	/* no buffering for ordered frames */
425 	if (ieee80211_has_order(hdr->frame_control))
426 		return TX_CONTINUE;
427 
428 	if (ieee80211_is_probe_req(hdr->frame_control))
429 		return TX_CONTINUE;
430 
431 	if (ieee80211_hw_check(&tx->local->hw, QUEUE_CONTROL))
432 		info->hw_queue = tx->sdata->vif.cab_queue;
433 
434 	/* no stations in PS mode */
435 	if (!atomic_read(&ps->num_sta_ps))
436 		return TX_CONTINUE;
437 
438 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
439 
440 	/* device releases frame after DTIM beacon */
441 	if (!ieee80211_hw_check(&tx->local->hw, HOST_BROADCAST_PS_BUFFERING))
442 		return TX_CONTINUE;
443 
444 	/* buffered in mac80211 */
445 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
446 		purge_old_ps_buffers(tx->local);
447 
448 	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
449 		ps_dbg(tx->sdata,
450 		       "BC TX buffer full - dropping the oldest frame\n");
451 		dev_kfree_skb(skb_dequeue(&ps->bc_buf));
452 	} else
453 		tx->local->total_ps_buffered++;
454 
455 	skb_queue_tail(&ps->bc_buf, tx->skb);
456 
457 	return TX_QUEUED;
458 }
459 
460 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
461 			     struct sk_buff *skb)
462 {
463 	if (!ieee80211_is_mgmt(fc))
464 		return 0;
465 
466 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
467 		return 0;
468 
469 	if (!ieee80211_is_robust_mgmt_frame(skb))
470 		return 0;
471 
472 	return 1;
473 }
474 
475 static ieee80211_tx_result
476 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
477 {
478 	struct sta_info *sta = tx->sta;
479 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
480 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
481 	struct ieee80211_local *local = tx->local;
482 
483 	if (unlikely(!sta))
484 		return TX_CONTINUE;
485 
486 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
487 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
488 		      test_sta_flag(sta, WLAN_STA_PS_DELIVER)) &&
489 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
490 		int ac = skb_get_queue_mapping(tx->skb);
491 
492 		if (ieee80211_is_mgmt(hdr->frame_control) &&
493 		    !ieee80211_is_bufferable_mmpdu(hdr->frame_control)) {
494 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
495 			return TX_CONTINUE;
496 		}
497 
498 		ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
499 		       sta->sta.addr, sta->sta.aid, ac);
500 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
501 			purge_old_ps_buffers(tx->local);
502 
503 		/* sync with ieee80211_sta_ps_deliver_wakeup */
504 		spin_lock(&sta->ps_lock);
505 		/*
506 		 * STA woke up the meantime and all the frames on ps_tx_buf have
507 		 * been queued to pending queue. No reordering can happen, go
508 		 * ahead and Tx the packet.
509 		 */
510 		if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
511 		    !test_sta_flag(sta, WLAN_STA_PS_DRIVER) &&
512 		    !test_sta_flag(sta, WLAN_STA_PS_DELIVER)) {
513 			spin_unlock(&sta->ps_lock);
514 			return TX_CONTINUE;
515 		}
516 
517 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
518 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
519 			ps_dbg(tx->sdata,
520 			       "STA %pM TX buffer for AC %d full - dropping oldest frame\n",
521 			       sta->sta.addr, ac);
522 			ieee80211_free_txskb(&local->hw, old);
523 		} else
524 			tx->local->total_ps_buffered++;
525 
526 		info->control.jiffies = jiffies;
527 		info->control.vif = &tx->sdata->vif;
528 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
529 		info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
530 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
531 		spin_unlock(&sta->ps_lock);
532 
533 		if (!timer_pending(&local->sta_cleanup))
534 			mod_timer(&local->sta_cleanup,
535 				  round_jiffies(jiffies +
536 						STA_INFO_CLEANUP_INTERVAL));
537 
538 		/*
539 		 * We queued up some frames, so the TIM bit might
540 		 * need to be set, recalculate it.
541 		 */
542 		sta_info_recalc_tim(sta);
543 
544 		return TX_QUEUED;
545 	} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
546 		ps_dbg(tx->sdata,
547 		       "STA %pM in PS mode, but polling/in SP -> send frame\n",
548 		       sta->sta.addr);
549 	}
550 
551 	return TX_CONTINUE;
552 }
553 
554 static ieee80211_tx_result debug_noinline
555 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
556 {
557 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
558 		return TX_CONTINUE;
559 
560 	if (tx->flags & IEEE80211_TX_UNICAST)
561 		return ieee80211_tx_h_unicast_ps_buf(tx);
562 	else
563 		return ieee80211_tx_h_multicast_ps_buf(tx);
564 }
565 
566 static ieee80211_tx_result debug_noinline
567 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
568 {
569 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
570 
571 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol)) {
572 		if (tx->sdata->control_port_no_encrypt)
573 			info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
574 		info->control.flags |= IEEE80211_TX_CTRL_PORT_CTRL_PROTO;
575 		info->flags |= IEEE80211_TX_CTL_USE_MINRATE;
576 	}
577 
578 	return TX_CONTINUE;
579 }
580 
581 static ieee80211_tx_result debug_noinline
582 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
583 {
584 	struct ieee80211_key *key;
585 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
586 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
587 
588 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
589 		tx->key = NULL;
590 	else if (tx->sta &&
591 		 (key = rcu_dereference(tx->sta->ptk[tx->sta->ptk_idx])))
592 		tx->key = key;
593 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
594 		 is_multicast_ether_addr(hdr->addr1) &&
595 		 ieee80211_is_robust_mgmt_frame(tx->skb) &&
596 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
597 		tx->key = key;
598 	else if (is_multicast_ether_addr(hdr->addr1) &&
599 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
600 		tx->key = key;
601 	else if (!is_multicast_ether_addr(hdr->addr1) &&
602 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
603 		tx->key = key;
604 	else
605 		tx->key = NULL;
606 
607 	if (tx->key) {
608 		bool skip_hw = false;
609 
610 		/* TODO: add threshold stuff again */
611 
612 		switch (tx->key->conf.cipher) {
613 		case WLAN_CIPHER_SUITE_WEP40:
614 		case WLAN_CIPHER_SUITE_WEP104:
615 		case WLAN_CIPHER_SUITE_TKIP:
616 			if (!ieee80211_is_data_present(hdr->frame_control))
617 				tx->key = NULL;
618 			break;
619 		case WLAN_CIPHER_SUITE_CCMP:
620 		case WLAN_CIPHER_SUITE_CCMP_256:
621 		case WLAN_CIPHER_SUITE_GCMP:
622 		case WLAN_CIPHER_SUITE_GCMP_256:
623 			if (!ieee80211_is_data_present(hdr->frame_control) &&
624 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
625 					       tx->skb))
626 				tx->key = NULL;
627 			else
628 				skip_hw = (tx->key->conf.flags &
629 					   IEEE80211_KEY_FLAG_SW_MGMT_TX) &&
630 					ieee80211_is_mgmt(hdr->frame_control);
631 			break;
632 		case WLAN_CIPHER_SUITE_AES_CMAC:
633 		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
634 		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
635 		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
636 			if (!ieee80211_is_mgmt(hdr->frame_control))
637 				tx->key = NULL;
638 			break;
639 		}
640 
641 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED &&
642 			     !ieee80211_is_deauth(hdr->frame_control)))
643 			return TX_DROP;
644 
645 		if (!skip_hw && tx->key &&
646 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
647 			info->control.hw_key = &tx->key->conf;
648 	}
649 
650 	return TX_CONTINUE;
651 }
652 
653 static ieee80211_tx_result debug_noinline
654 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
655 {
656 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
657 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
658 	struct ieee80211_supported_band *sband;
659 	u32 len;
660 	struct ieee80211_tx_rate_control txrc;
661 	struct ieee80211_sta_rates *ratetbl = NULL;
662 	bool assoc = false;
663 
664 	memset(&txrc, 0, sizeof(txrc));
665 
666 	sband = tx->local->hw.wiphy->bands[info->band];
667 
668 	len = min_t(u32, tx->skb->len + FCS_LEN,
669 			 tx->local->hw.wiphy->frag_threshold);
670 
671 	/* set up the tx rate control struct we give the RC algo */
672 	txrc.hw = &tx->local->hw;
673 	txrc.sband = sband;
674 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
675 	txrc.skb = tx->skb;
676 	txrc.reported_rate.idx = -1;
677 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
678 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
679 		txrc.max_rate_idx = -1;
680 	else
681 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
682 
683 	if (tx->sdata->rc_has_mcs_mask[info->band])
684 		txrc.rate_idx_mcs_mask =
685 			tx->sdata->rc_rateidx_mcs_mask[info->band];
686 
687 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
688 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
689 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC ||
690 		    tx->sdata->vif.type == NL80211_IFTYPE_OCB);
691 
692 	/* set up RTS protection if desired */
693 	if (len > tx->local->hw.wiphy->rts_threshold) {
694 		txrc.rts = true;
695 	}
696 
697 	info->control.use_rts = txrc.rts;
698 	info->control.use_cts_prot = tx->sdata->vif.bss_conf.use_cts_prot;
699 
700 	/*
701 	 * Use short preamble if the BSS can handle it, but not for
702 	 * management frames unless we know the receiver can handle
703 	 * that -- the management frame might be to a station that
704 	 * just wants a probe response.
705 	 */
706 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
707 	    (ieee80211_is_data(hdr->frame_control) ||
708 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
709 		txrc.short_preamble = true;
710 
711 	info->control.short_preamble = txrc.short_preamble;
712 
713 	/* don't ask rate control when rate already injected via radiotap */
714 	if (info->control.flags & IEEE80211_TX_CTRL_RATE_INJECT)
715 		return TX_CONTINUE;
716 
717 	if (tx->sta)
718 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
719 
720 	/*
721 	 * Lets not bother rate control if we're associated and cannot
722 	 * talk to the sta. This should not happen.
723 	 */
724 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
725 		 !rate_usable_index_exists(sband, &tx->sta->sta),
726 		 "%s: Dropped data frame as no usable bitrate found while "
727 		 "scanning and associated. Target station: "
728 		 "%pM on %d GHz band\n",
729 		 tx->sdata->name, hdr->addr1,
730 		 info->band ? 5 : 2))
731 		return TX_DROP;
732 
733 	/*
734 	 * If we're associated with the sta at this point we know we can at
735 	 * least send the frame at the lowest bit rate.
736 	 */
737 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
738 
739 	if (tx->sta && !info->control.skip_table)
740 		ratetbl = rcu_dereference(tx->sta->sta.rates);
741 
742 	if (unlikely(info->control.rates[0].idx < 0)) {
743 		if (ratetbl) {
744 			struct ieee80211_tx_rate rate = {
745 				.idx = ratetbl->rate[0].idx,
746 				.flags = ratetbl->rate[0].flags,
747 				.count = ratetbl->rate[0].count
748 			};
749 
750 			if (ratetbl->rate[0].idx < 0)
751 				return TX_DROP;
752 
753 			tx->rate = rate;
754 		} else {
755 			return TX_DROP;
756 		}
757 	} else {
758 		tx->rate = info->control.rates[0];
759 	}
760 
761 	if (txrc.reported_rate.idx < 0) {
762 		txrc.reported_rate = tx->rate;
763 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
764 			tx->sta->tx_stats.last_rate = txrc.reported_rate;
765 	} else if (tx->sta)
766 		tx->sta->tx_stats.last_rate = txrc.reported_rate;
767 
768 	if (ratetbl)
769 		return TX_CONTINUE;
770 
771 	if (unlikely(!info->control.rates[0].count))
772 		info->control.rates[0].count = 1;
773 
774 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
775 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
776 		info->control.rates[0].count = 1;
777 
778 	return TX_CONTINUE;
779 }
780 
781 static __le16 ieee80211_tx_next_seq(struct sta_info *sta, int tid)
782 {
783 	u16 *seq = &sta->tid_seq[tid];
784 	__le16 ret = cpu_to_le16(*seq);
785 
786 	/* Increase the sequence number. */
787 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
788 
789 	return ret;
790 }
791 
792 static ieee80211_tx_result debug_noinline
793 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
794 {
795 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
796 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
797 	u8 *qc;
798 	int tid;
799 
800 	/*
801 	 * Packet injection may want to control the sequence
802 	 * number, if we have no matching interface then we
803 	 * neither assign one ourselves nor ask the driver to.
804 	 */
805 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
806 		return TX_CONTINUE;
807 
808 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
809 		return TX_CONTINUE;
810 
811 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
812 		return TX_CONTINUE;
813 
814 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
815 		return TX_CONTINUE;
816 
817 	/*
818 	 * Anything but QoS data that has a sequence number field
819 	 * (is long enough) gets a sequence number from the global
820 	 * counter.  QoS data frames with a multicast destination
821 	 * also use the global counter (802.11-2012 9.3.2.10).
822 	 */
823 	if (!ieee80211_is_data_qos(hdr->frame_control) ||
824 	    is_multicast_ether_addr(hdr->addr1)) {
825 		/* driver should assign sequence number */
826 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
827 		/* for pure STA mode without beacons, we can do it */
828 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
829 		tx->sdata->sequence_number += 0x10;
830 		if (tx->sta)
831 			tx->sta->tx_stats.msdu[IEEE80211_NUM_TIDS]++;
832 		return TX_CONTINUE;
833 	}
834 
835 	/*
836 	 * This should be true for injected/management frames only, for
837 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
838 	 * above since they are not QoS-data frames.
839 	 */
840 	if (!tx->sta)
841 		return TX_CONTINUE;
842 
843 	/* include per-STA, per-TID sequence counter */
844 
845 	qc = ieee80211_get_qos_ctl(hdr);
846 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
847 	tx->sta->tx_stats.msdu[tid]++;
848 
849 	if (!tx->sta->sta.txq[0])
850 		hdr->seq_ctrl = ieee80211_tx_next_seq(tx->sta, tid);
851 
852 	return TX_CONTINUE;
853 }
854 
855 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
856 			      struct sk_buff *skb, int hdrlen,
857 			      int frag_threshold)
858 {
859 	struct ieee80211_local *local = tx->local;
860 	struct ieee80211_tx_info *info;
861 	struct sk_buff *tmp;
862 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
863 	int pos = hdrlen + per_fragm;
864 	int rem = skb->len - hdrlen - per_fragm;
865 
866 	if (WARN_ON(rem < 0))
867 		return -EINVAL;
868 
869 	/* first fragment was already added to queue by caller */
870 
871 	while (rem) {
872 		int fraglen = per_fragm;
873 
874 		if (fraglen > rem)
875 			fraglen = rem;
876 		rem -= fraglen;
877 		tmp = dev_alloc_skb(local->tx_headroom +
878 				    frag_threshold +
879 				    tx->sdata->encrypt_headroom +
880 				    IEEE80211_ENCRYPT_TAILROOM);
881 		if (!tmp)
882 			return -ENOMEM;
883 
884 		__skb_queue_tail(&tx->skbs, tmp);
885 
886 		skb_reserve(tmp,
887 			    local->tx_headroom + tx->sdata->encrypt_headroom);
888 
889 		/* copy control information */
890 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
891 
892 		info = IEEE80211_SKB_CB(tmp);
893 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
894 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
895 
896 		if (rem)
897 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
898 
899 		skb_copy_queue_mapping(tmp, skb);
900 		tmp->priority = skb->priority;
901 		tmp->dev = skb->dev;
902 
903 		/* copy header and data */
904 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
905 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
906 
907 		pos += fraglen;
908 	}
909 
910 	/* adjust first fragment's length */
911 	skb_trim(skb, hdrlen + per_fragm);
912 	return 0;
913 }
914 
915 static ieee80211_tx_result debug_noinline
916 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
917 {
918 	struct sk_buff *skb = tx->skb;
919 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
920 	struct ieee80211_hdr *hdr = (void *)skb->data;
921 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
922 	int hdrlen;
923 	int fragnum;
924 
925 	/* no matter what happens, tx->skb moves to tx->skbs */
926 	__skb_queue_tail(&tx->skbs, skb);
927 	tx->skb = NULL;
928 
929 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
930 		return TX_CONTINUE;
931 
932 	if (tx->local->ops->set_frag_threshold)
933 		return TX_CONTINUE;
934 
935 	/*
936 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
937 	 * This scenario is handled in ieee80211_tx_prepare but extra
938 	 * caution taken here as fragmented ampdu may cause Tx stop.
939 	 */
940 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
941 		return TX_DROP;
942 
943 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
944 
945 	/* internal error, why isn't DONTFRAG set? */
946 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
947 		return TX_DROP;
948 
949 	/*
950 	 * Now fragment the frame. This will allocate all the fragments and
951 	 * chain them (using skb as the first fragment) to skb->next.
952 	 * During transmission, we will remove the successfully transmitted
953 	 * fragments from this list. When the low-level driver rejects one
954 	 * of the fragments then we will simply pretend to accept the skb
955 	 * but store it away as pending.
956 	 */
957 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
958 		return TX_DROP;
959 
960 	/* update duration/seq/flags of fragments */
961 	fragnum = 0;
962 
963 	skb_queue_walk(&tx->skbs, skb) {
964 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
965 
966 		hdr = (void *)skb->data;
967 		info = IEEE80211_SKB_CB(skb);
968 
969 		if (!skb_queue_is_last(&tx->skbs, skb)) {
970 			hdr->frame_control |= morefrags;
971 			/*
972 			 * No multi-rate retries for fragmented frames, that
973 			 * would completely throw off the NAV at other STAs.
974 			 */
975 			info->control.rates[1].idx = -1;
976 			info->control.rates[2].idx = -1;
977 			info->control.rates[3].idx = -1;
978 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 4);
979 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
980 		} else {
981 			hdr->frame_control &= ~morefrags;
982 		}
983 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
984 		fragnum++;
985 	}
986 
987 	return TX_CONTINUE;
988 }
989 
990 static ieee80211_tx_result debug_noinline
991 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
992 {
993 	struct sk_buff *skb;
994 	int ac = -1;
995 
996 	if (!tx->sta)
997 		return TX_CONTINUE;
998 
999 	skb_queue_walk(&tx->skbs, skb) {
1000 		ac = skb_get_queue_mapping(skb);
1001 		tx->sta->tx_stats.bytes[ac] += skb->len;
1002 	}
1003 	if (ac >= 0)
1004 		tx->sta->tx_stats.packets[ac]++;
1005 
1006 	return TX_CONTINUE;
1007 }
1008 
1009 static ieee80211_tx_result debug_noinline
1010 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
1011 {
1012 	if (!tx->key)
1013 		return TX_CONTINUE;
1014 
1015 	switch (tx->key->conf.cipher) {
1016 	case WLAN_CIPHER_SUITE_WEP40:
1017 	case WLAN_CIPHER_SUITE_WEP104:
1018 		return ieee80211_crypto_wep_encrypt(tx);
1019 	case WLAN_CIPHER_SUITE_TKIP:
1020 		return ieee80211_crypto_tkip_encrypt(tx);
1021 	case WLAN_CIPHER_SUITE_CCMP:
1022 		return ieee80211_crypto_ccmp_encrypt(
1023 			tx, IEEE80211_CCMP_MIC_LEN);
1024 	case WLAN_CIPHER_SUITE_CCMP_256:
1025 		return ieee80211_crypto_ccmp_encrypt(
1026 			tx, IEEE80211_CCMP_256_MIC_LEN);
1027 	case WLAN_CIPHER_SUITE_AES_CMAC:
1028 		return ieee80211_crypto_aes_cmac_encrypt(tx);
1029 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1030 		return ieee80211_crypto_aes_cmac_256_encrypt(tx);
1031 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1032 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1033 		return ieee80211_crypto_aes_gmac_encrypt(tx);
1034 	case WLAN_CIPHER_SUITE_GCMP:
1035 	case WLAN_CIPHER_SUITE_GCMP_256:
1036 		return ieee80211_crypto_gcmp_encrypt(tx);
1037 	default:
1038 		return ieee80211_crypto_hw_encrypt(tx);
1039 	}
1040 
1041 	return TX_DROP;
1042 }
1043 
1044 static ieee80211_tx_result debug_noinline
1045 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
1046 {
1047 	struct sk_buff *skb;
1048 	struct ieee80211_hdr *hdr;
1049 	int next_len;
1050 	bool group_addr;
1051 
1052 	skb_queue_walk(&tx->skbs, skb) {
1053 		hdr = (void *) skb->data;
1054 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
1055 			break; /* must not overwrite AID */
1056 		if (!skb_queue_is_last(&tx->skbs, skb)) {
1057 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
1058 			next_len = next->len;
1059 		} else
1060 			next_len = 0;
1061 		group_addr = is_multicast_ether_addr(hdr->addr1);
1062 
1063 		hdr->duration_id =
1064 			ieee80211_duration(tx, skb, group_addr, next_len);
1065 	}
1066 
1067 	return TX_CONTINUE;
1068 }
1069 
1070 /* actual transmit path */
1071 
1072 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1073 				  struct sk_buff *skb,
1074 				  struct ieee80211_tx_info *info,
1075 				  struct tid_ampdu_tx *tid_tx,
1076 				  int tid)
1077 {
1078 	bool queued = false;
1079 	bool reset_agg_timer = false;
1080 	struct sk_buff *purge_skb = NULL;
1081 
1082 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1083 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1084 		reset_agg_timer = true;
1085 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1086 		/*
1087 		 * nothing -- this aggregation session is being started
1088 		 * but that might still fail with the driver
1089 		 */
1090 	} else if (!tx->sta->sta.txq[tid]) {
1091 		spin_lock(&tx->sta->lock);
1092 		/*
1093 		 * Need to re-check now, because we may get here
1094 		 *
1095 		 *  1) in the window during which the setup is actually
1096 		 *     already done, but not marked yet because not all
1097 		 *     packets are spliced over to the driver pending
1098 		 *     queue yet -- if this happened we acquire the lock
1099 		 *     either before or after the splice happens, but
1100 		 *     need to recheck which of these cases happened.
1101 		 *
1102 		 *  2) during session teardown, if the OPERATIONAL bit
1103 		 *     was cleared due to the teardown but the pointer
1104 		 *     hasn't been assigned NULL yet (or we loaded it
1105 		 *     before it was assigned) -- in this case it may
1106 		 *     now be NULL which means we should just let the
1107 		 *     packet pass through because splicing the frames
1108 		 *     back is already done.
1109 		 */
1110 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1111 
1112 		if (!tid_tx) {
1113 			/* do nothing, let packet pass through */
1114 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1115 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1116 			reset_agg_timer = true;
1117 		} else {
1118 			queued = true;
1119 			if (info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER) {
1120 				clear_sta_flag(tx->sta, WLAN_STA_SP);
1121 				ps_dbg(tx->sta->sdata,
1122 				       "STA %pM aid %d: SP frame queued, close the SP w/o telling the peer\n",
1123 				       tx->sta->sta.addr, tx->sta->sta.aid);
1124 			}
1125 			info->control.vif = &tx->sdata->vif;
1126 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1127 			info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
1128 			__skb_queue_tail(&tid_tx->pending, skb);
1129 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1130 				purge_skb = __skb_dequeue(&tid_tx->pending);
1131 		}
1132 		spin_unlock(&tx->sta->lock);
1133 
1134 		if (purge_skb)
1135 			ieee80211_free_txskb(&tx->local->hw, purge_skb);
1136 	}
1137 
1138 	/* reset session timer */
1139 	if (reset_agg_timer && tid_tx->timeout)
1140 		tid_tx->last_tx = jiffies;
1141 
1142 	return queued;
1143 }
1144 
1145 /*
1146  * initialises @tx
1147  * pass %NULL for the station if unknown, a valid pointer if known
1148  * or an ERR_PTR() if the station is known not to exist
1149  */
1150 static ieee80211_tx_result
1151 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1152 		     struct ieee80211_tx_data *tx,
1153 		     struct sta_info *sta, struct sk_buff *skb)
1154 {
1155 	struct ieee80211_local *local = sdata->local;
1156 	struct ieee80211_hdr *hdr;
1157 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1158 	int tid;
1159 	u8 *qc;
1160 
1161 	memset(tx, 0, sizeof(*tx));
1162 	tx->skb = skb;
1163 	tx->local = local;
1164 	tx->sdata = sdata;
1165 	__skb_queue_head_init(&tx->skbs);
1166 
1167 	/*
1168 	 * If this flag is set to true anywhere, and we get here,
1169 	 * we are doing the needed processing, so remove the flag
1170 	 * now.
1171 	 */
1172 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1173 
1174 	hdr = (struct ieee80211_hdr *) skb->data;
1175 
1176 	if (likely(sta)) {
1177 		if (!IS_ERR(sta))
1178 			tx->sta = sta;
1179 	} else {
1180 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1181 			tx->sta = rcu_dereference(sdata->u.vlan.sta);
1182 			if (!tx->sta && sdata->wdev.use_4addr)
1183 				return TX_DROP;
1184 		} else if (info->flags & (IEEE80211_TX_INTFL_NL80211_FRAME_TX |
1185 					  IEEE80211_TX_CTL_INJECTED) ||
1186 			   tx->sdata->control_port_protocol == tx->skb->protocol) {
1187 			tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1188 		}
1189 		if (!tx->sta && !is_multicast_ether_addr(hdr->addr1))
1190 			tx->sta = sta_info_get(sdata, hdr->addr1);
1191 	}
1192 
1193 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1194 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1195 	    ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
1196 	    !ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW)) {
1197 		struct tid_ampdu_tx *tid_tx;
1198 
1199 		qc = ieee80211_get_qos_ctl(hdr);
1200 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1201 
1202 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1203 		if (tid_tx) {
1204 			bool queued;
1205 
1206 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1207 						       tid_tx, tid);
1208 
1209 			if (unlikely(queued))
1210 				return TX_QUEUED;
1211 		}
1212 	}
1213 
1214 	if (is_multicast_ether_addr(hdr->addr1)) {
1215 		tx->flags &= ~IEEE80211_TX_UNICAST;
1216 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1217 	} else
1218 		tx->flags |= IEEE80211_TX_UNICAST;
1219 
1220 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1221 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1222 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1223 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1224 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1225 	}
1226 
1227 	if (!tx->sta)
1228 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1229 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT)) {
1230 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1231 		ieee80211_check_fast_xmit(tx->sta);
1232 	}
1233 
1234 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1235 
1236 	return TX_CONTINUE;
1237 }
1238 
1239 static void ieee80211_drv_tx(struct ieee80211_local *local,
1240 			     struct ieee80211_vif *vif,
1241 			     struct ieee80211_sta *pubsta,
1242 			     struct sk_buff *skb)
1243 {
1244 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1245 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1246 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1247 	struct ieee80211_tx_control control = {
1248 		.sta = pubsta,
1249 	};
1250 	struct ieee80211_txq *txq = NULL;
1251 	struct txq_info *txqi;
1252 	u8 ac;
1253 
1254 	if ((info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) ||
1255 	    (info->control.flags & IEEE80211_TX_CTRL_PS_RESPONSE))
1256 		goto tx_normal;
1257 
1258 	if (!ieee80211_is_data(hdr->frame_control))
1259 		goto tx_normal;
1260 
1261 	if (pubsta) {
1262 		u8 tid = skb->priority & IEEE80211_QOS_CTL_TID_MASK;
1263 
1264 		txq = pubsta->txq[tid];
1265 	} else if (vif) {
1266 		txq = vif->txq;
1267 	}
1268 
1269 	if (!txq)
1270 		goto tx_normal;
1271 
1272 	ac = txq->ac;
1273 	txqi = to_txq_info(txq);
1274 	atomic_inc(&sdata->txqs_len[ac]);
1275 	if (atomic_read(&sdata->txqs_len[ac]) >= local->hw.txq_ac_max_pending)
1276 		netif_stop_subqueue(sdata->dev, ac);
1277 
1278 	spin_lock_bh(&txqi->queue.lock);
1279 	txqi->byte_cnt += skb->len;
1280 	__skb_queue_tail(&txqi->queue, skb);
1281 	spin_unlock_bh(&txqi->queue.lock);
1282 
1283 	drv_wake_tx_queue(local, txqi);
1284 
1285 	return;
1286 
1287 tx_normal:
1288 	drv_tx(local, &control, skb);
1289 }
1290 
1291 struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
1292 				     struct ieee80211_txq *txq)
1293 {
1294 	struct ieee80211_local *local = hw_to_local(hw);
1295 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->vif);
1296 	struct txq_info *txqi = container_of(txq, struct txq_info, txq);
1297 	struct ieee80211_hdr *hdr;
1298 	struct sk_buff *skb = NULL;
1299 	u8 ac = txq->ac;
1300 
1301 	spin_lock_bh(&txqi->queue.lock);
1302 
1303 	if (test_bit(IEEE80211_TXQ_STOP, &txqi->flags))
1304 		goto out;
1305 
1306 	skb = __skb_dequeue(&txqi->queue);
1307 	if (!skb)
1308 		goto out;
1309 
1310 	txqi->byte_cnt -= skb->len;
1311 
1312 	atomic_dec(&sdata->txqs_len[ac]);
1313 	if (__netif_subqueue_stopped(sdata->dev, ac))
1314 		ieee80211_propagate_queue_wake(local, sdata->vif.hw_queue[ac]);
1315 
1316 	hdr = (struct ieee80211_hdr *)skb->data;
1317 	if (txq->sta && ieee80211_is_data_qos(hdr->frame_control)) {
1318 		struct sta_info *sta = container_of(txq->sta, struct sta_info,
1319 						    sta);
1320 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1321 
1322 		hdr->seq_ctrl = ieee80211_tx_next_seq(sta, txq->tid);
1323 		if (test_bit(IEEE80211_TXQ_AMPDU, &txqi->flags))
1324 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1325 		else
1326 			info->flags &= ~IEEE80211_TX_CTL_AMPDU;
1327 	}
1328 
1329 out:
1330 	spin_unlock_bh(&txqi->queue.lock);
1331 
1332 	if (skb && skb_has_frag_list(skb) &&
1333 	    !ieee80211_hw_check(&local->hw, TX_FRAG_LIST))
1334 		skb_linearize(skb);
1335 
1336 	return skb;
1337 }
1338 EXPORT_SYMBOL(ieee80211_tx_dequeue);
1339 
1340 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1341 			       struct ieee80211_vif *vif,
1342 			       struct ieee80211_sta *sta,
1343 			       struct sk_buff_head *skbs,
1344 			       bool txpending)
1345 {
1346 	struct sk_buff *skb, *tmp;
1347 	unsigned long flags;
1348 
1349 	skb_queue_walk_safe(skbs, skb, tmp) {
1350 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1351 		int q = info->hw_queue;
1352 
1353 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1354 		if (WARN_ON_ONCE(q >= local->hw.queues)) {
1355 			__skb_unlink(skb, skbs);
1356 			ieee80211_free_txskb(&local->hw, skb);
1357 			continue;
1358 		}
1359 #endif
1360 
1361 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1362 		if (local->queue_stop_reasons[q] ||
1363 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1364 			if (unlikely(info->flags &
1365 				     IEEE80211_TX_INTFL_OFFCHAN_TX_OK)) {
1366 				if (local->queue_stop_reasons[q] &
1367 				    ~BIT(IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL)) {
1368 					/*
1369 					 * Drop off-channel frames if queues
1370 					 * are stopped for any reason other
1371 					 * than off-channel operation. Never
1372 					 * queue them.
1373 					 */
1374 					spin_unlock_irqrestore(
1375 						&local->queue_stop_reason_lock,
1376 						flags);
1377 					ieee80211_purge_tx_queue(&local->hw,
1378 								 skbs);
1379 					return true;
1380 				}
1381 			} else {
1382 
1383 				/*
1384 				 * Since queue is stopped, queue up frames for
1385 				 * later transmission from the tx-pending
1386 				 * tasklet when the queue is woken again.
1387 				 */
1388 				if (txpending)
1389 					skb_queue_splice_init(skbs,
1390 							      &local->pending[q]);
1391 				else
1392 					skb_queue_splice_tail_init(skbs,
1393 								   &local->pending[q]);
1394 
1395 				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1396 						       flags);
1397 				return false;
1398 			}
1399 		}
1400 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1401 
1402 		info->control.vif = vif;
1403 
1404 		__skb_unlink(skb, skbs);
1405 		ieee80211_drv_tx(local, vif, sta, skb);
1406 	}
1407 
1408 	return true;
1409 }
1410 
1411 /*
1412  * Returns false if the frame couldn't be transmitted but was queued instead.
1413  */
1414 static bool __ieee80211_tx(struct ieee80211_local *local,
1415 			   struct sk_buff_head *skbs, int led_len,
1416 			   struct sta_info *sta, bool txpending)
1417 {
1418 	struct ieee80211_tx_info *info;
1419 	struct ieee80211_sub_if_data *sdata;
1420 	struct ieee80211_vif *vif;
1421 	struct ieee80211_sta *pubsta;
1422 	struct sk_buff *skb;
1423 	bool result = true;
1424 	__le16 fc;
1425 
1426 	if (WARN_ON(skb_queue_empty(skbs)))
1427 		return true;
1428 
1429 	skb = skb_peek(skbs);
1430 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1431 	info = IEEE80211_SKB_CB(skb);
1432 	sdata = vif_to_sdata(info->control.vif);
1433 	if (sta && !sta->uploaded)
1434 		sta = NULL;
1435 
1436 	if (sta)
1437 		pubsta = &sta->sta;
1438 	else
1439 		pubsta = NULL;
1440 
1441 	switch (sdata->vif.type) {
1442 	case NL80211_IFTYPE_MONITOR:
1443 		if (sdata->u.mntr_flags & MONITOR_FLAG_ACTIVE) {
1444 			vif = &sdata->vif;
1445 			break;
1446 		}
1447 		sdata = rcu_dereference(local->monitor_sdata);
1448 		if (sdata) {
1449 			vif = &sdata->vif;
1450 			info->hw_queue =
1451 				vif->hw_queue[skb_get_queue_mapping(skb)];
1452 		} else if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL)) {
1453 			ieee80211_purge_tx_queue(&local->hw, skbs);
1454 			return true;
1455 		} else
1456 			vif = NULL;
1457 		break;
1458 	case NL80211_IFTYPE_AP_VLAN:
1459 		sdata = container_of(sdata->bss,
1460 				     struct ieee80211_sub_if_data, u.ap);
1461 		/* fall through */
1462 	default:
1463 		vif = &sdata->vif;
1464 		break;
1465 	}
1466 
1467 	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1468 				    txpending);
1469 
1470 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1471 
1472 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1473 
1474 	return result;
1475 }
1476 
1477 /*
1478  * Invoke TX handlers, return 0 on success and non-zero if the
1479  * frame was dropped or queued.
1480  */
1481 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1482 {
1483 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1484 	ieee80211_tx_result res = TX_DROP;
1485 
1486 #define CALL_TXH(txh) \
1487 	do {				\
1488 		res = txh(tx);		\
1489 		if (res != TX_CONTINUE)	\
1490 			goto txh_done;	\
1491 	} while (0)
1492 
1493 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1494 	CALL_TXH(ieee80211_tx_h_check_assoc);
1495 	CALL_TXH(ieee80211_tx_h_ps_buf);
1496 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1497 	CALL_TXH(ieee80211_tx_h_select_key);
1498 	if (!ieee80211_hw_check(&tx->local->hw, HAS_RATE_CONTROL))
1499 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1500 
1501 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1502 		__skb_queue_tail(&tx->skbs, tx->skb);
1503 		tx->skb = NULL;
1504 		goto txh_done;
1505 	}
1506 
1507 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1508 	CALL_TXH(ieee80211_tx_h_sequence);
1509 	CALL_TXH(ieee80211_tx_h_fragment);
1510 	/* handlers after fragment must be aware of tx info fragmentation! */
1511 	CALL_TXH(ieee80211_tx_h_stats);
1512 	CALL_TXH(ieee80211_tx_h_encrypt);
1513 	if (!ieee80211_hw_check(&tx->local->hw, HAS_RATE_CONTROL))
1514 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1515 #undef CALL_TXH
1516 
1517  txh_done:
1518 	if (unlikely(res == TX_DROP)) {
1519 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1520 		if (tx->skb)
1521 			ieee80211_free_txskb(&tx->local->hw, tx->skb);
1522 		else
1523 			ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
1524 		return -1;
1525 	} else if (unlikely(res == TX_QUEUED)) {
1526 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1527 		return -1;
1528 	}
1529 
1530 	return 0;
1531 }
1532 
1533 bool ieee80211_tx_prepare_skb(struct ieee80211_hw *hw,
1534 			      struct ieee80211_vif *vif, struct sk_buff *skb,
1535 			      int band, struct ieee80211_sta **sta)
1536 {
1537 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1538 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1539 	struct ieee80211_tx_data tx;
1540 	struct sk_buff *skb2;
1541 
1542 	if (ieee80211_tx_prepare(sdata, &tx, NULL, skb) == TX_DROP)
1543 		return false;
1544 
1545 	info->band = band;
1546 	info->control.vif = vif;
1547 	info->hw_queue = vif->hw_queue[skb_get_queue_mapping(skb)];
1548 
1549 	if (invoke_tx_handlers(&tx))
1550 		return false;
1551 
1552 	if (sta) {
1553 		if (tx.sta)
1554 			*sta = &tx.sta->sta;
1555 		else
1556 			*sta = NULL;
1557 	}
1558 
1559 	/* this function isn't suitable for fragmented data frames */
1560 	skb2 = __skb_dequeue(&tx.skbs);
1561 	if (WARN_ON(skb2 != skb || !skb_queue_empty(&tx.skbs))) {
1562 		ieee80211_free_txskb(hw, skb2);
1563 		ieee80211_purge_tx_queue(hw, &tx.skbs);
1564 		return false;
1565 	}
1566 
1567 	return true;
1568 }
1569 EXPORT_SYMBOL(ieee80211_tx_prepare_skb);
1570 
1571 /*
1572  * Returns false if the frame couldn't be transmitted but was queued instead.
1573  */
1574 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1575 			 struct sta_info *sta, struct sk_buff *skb,
1576 			 bool txpending)
1577 {
1578 	struct ieee80211_local *local = sdata->local;
1579 	struct ieee80211_tx_data tx;
1580 	ieee80211_tx_result res_prepare;
1581 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1582 	bool result = true;
1583 	int led_len;
1584 
1585 	if (unlikely(skb->len < 10)) {
1586 		dev_kfree_skb(skb);
1587 		return true;
1588 	}
1589 
1590 	/* initialises tx */
1591 	led_len = skb->len;
1592 	res_prepare = ieee80211_tx_prepare(sdata, &tx, sta, skb);
1593 
1594 	if (unlikely(res_prepare == TX_DROP)) {
1595 		ieee80211_free_txskb(&local->hw, skb);
1596 		return true;
1597 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1598 		return true;
1599 	}
1600 
1601 	/* set up hw_queue value early */
1602 	if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
1603 	    !ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
1604 		info->hw_queue =
1605 			sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
1606 
1607 	if (!invoke_tx_handlers(&tx))
1608 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1609 					tx.sta, txpending);
1610 
1611 	return result;
1612 }
1613 
1614 /* device xmit handlers */
1615 
1616 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1617 				struct sk_buff *skb,
1618 				int head_need, bool may_encrypt)
1619 {
1620 	struct ieee80211_local *local = sdata->local;
1621 	int tail_need = 0;
1622 
1623 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1624 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1625 		tail_need -= skb_tailroom(skb);
1626 		tail_need = max_t(int, tail_need, 0);
1627 	}
1628 
1629 	if (skb_cloned(skb) &&
1630 	    (!ieee80211_hw_check(&local->hw, SUPPORTS_CLONED_SKBS) ||
1631 	     !skb_clone_writable(skb, ETH_HLEN) ||
1632 	     (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt)))
1633 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1634 	else if (head_need || tail_need)
1635 		I802_DEBUG_INC(local->tx_expand_skb_head);
1636 	else
1637 		return 0;
1638 
1639 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1640 		wiphy_debug(local->hw.wiphy,
1641 			    "failed to reallocate TX buffer\n");
1642 		return -ENOMEM;
1643 	}
1644 
1645 	return 0;
1646 }
1647 
1648 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1649 		    struct sta_info *sta, struct sk_buff *skb)
1650 {
1651 	struct ieee80211_local *local = sdata->local;
1652 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1653 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1654 	int headroom;
1655 	bool may_encrypt;
1656 
1657 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1658 
1659 	headroom = local->tx_headroom;
1660 	if (may_encrypt)
1661 		headroom += sdata->encrypt_headroom;
1662 	headroom -= skb_headroom(skb);
1663 	headroom = max_t(int, 0, headroom);
1664 
1665 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1666 		ieee80211_free_txskb(&local->hw, skb);
1667 		return;
1668 	}
1669 
1670 	hdr = (struct ieee80211_hdr *) skb->data;
1671 	info->control.vif = &sdata->vif;
1672 
1673 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1674 		if (ieee80211_is_data(hdr->frame_control) &&
1675 		    is_unicast_ether_addr(hdr->addr1)) {
1676 			if (mesh_nexthop_resolve(sdata, skb))
1677 				return; /* skb queued: don't free */
1678 		} else {
1679 			ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
1680 		}
1681 	}
1682 
1683 	ieee80211_set_qos_hdr(sdata, skb);
1684 	ieee80211_tx(sdata, sta, skb, false);
1685 }
1686 
1687 static bool ieee80211_parse_tx_radiotap(struct ieee80211_local *local,
1688 					struct sk_buff *skb)
1689 {
1690 	struct ieee80211_radiotap_iterator iterator;
1691 	struct ieee80211_radiotap_header *rthdr =
1692 		(struct ieee80211_radiotap_header *) skb->data;
1693 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1694 	struct ieee80211_supported_band *sband =
1695 		local->hw.wiphy->bands[info->band];
1696 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1697 						   NULL);
1698 	u16 txflags;
1699 	u16 rate = 0;
1700 	bool rate_found = false;
1701 	u8 rate_retries = 0;
1702 	u16 rate_flags = 0;
1703 	u8 mcs_known, mcs_flags, mcs_bw;
1704 	u16 vht_known;
1705 	u8 vht_mcs = 0, vht_nss = 0;
1706 	int i;
1707 
1708 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1709 		       IEEE80211_TX_CTL_DONTFRAG;
1710 
1711 	/*
1712 	 * for every radiotap entry that is present
1713 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1714 	 * entries present, or -EINVAL on error)
1715 	 */
1716 
1717 	while (!ret) {
1718 		ret = ieee80211_radiotap_iterator_next(&iterator);
1719 
1720 		if (ret)
1721 			continue;
1722 
1723 		/* see if this argument is something we can use */
1724 		switch (iterator.this_arg_index) {
1725 		/*
1726 		 * You must take care when dereferencing iterator.this_arg
1727 		 * for multibyte types... the pointer is not aligned.  Use
1728 		 * get_unaligned((type *)iterator.this_arg) to dereference
1729 		 * iterator.this_arg for type "type" safely on all arches.
1730 		*/
1731 		case IEEE80211_RADIOTAP_FLAGS:
1732 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1733 				/*
1734 				 * this indicates that the skb we have been
1735 				 * handed has the 32-bit FCS CRC at the end...
1736 				 * we should react to that by snipping it off
1737 				 * because it will be recomputed and added
1738 				 * on transmission
1739 				 */
1740 				if (skb->len < (iterator._max_length + FCS_LEN))
1741 					return false;
1742 
1743 				skb_trim(skb, skb->len - FCS_LEN);
1744 			}
1745 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1746 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1747 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1748 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1749 			break;
1750 
1751 		case IEEE80211_RADIOTAP_TX_FLAGS:
1752 			txflags = get_unaligned_le16(iterator.this_arg);
1753 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1754 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1755 			break;
1756 
1757 		case IEEE80211_RADIOTAP_RATE:
1758 			rate = *iterator.this_arg;
1759 			rate_flags = 0;
1760 			rate_found = true;
1761 			break;
1762 
1763 		case IEEE80211_RADIOTAP_DATA_RETRIES:
1764 			rate_retries = *iterator.this_arg;
1765 			break;
1766 
1767 		case IEEE80211_RADIOTAP_MCS:
1768 			mcs_known = iterator.this_arg[0];
1769 			mcs_flags = iterator.this_arg[1];
1770 			if (!(mcs_known & IEEE80211_RADIOTAP_MCS_HAVE_MCS))
1771 				break;
1772 
1773 			rate_found = true;
1774 			rate = iterator.this_arg[2];
1775 			rate_flags = IEEE80211_TX_RC_MCS;
1776 
1777 			if (mcs_known & IEEE80211_RADIOTAP_MCS_HAVE_GI &&
1778 			    mcs_flags & IEEE80211_RADIOTAP_MCS_SGI)
1779 				rate_flags |= IEEE80211_TX_RC_SHORT_GI;
1780 
1781 			mcs_bw = mcs_flags & IEEE80211_RADIOTAP_MCS_BW_MASK;
1782 			if (mcs_known & IEEE80211_RADIOTAP_MCS_HAVE_BW &&
1783 			    mcs_bw == IEEE80211_RADIOTAP_MCS_BW_40)
1784 				rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
1785 			break;
1786 
1787 		case IEEE80211_RADIOTAP_VHT:
1788 			vht_known = get_unaligned_le16(iterator.this_arg);
1789 			rate_found = true;
1790 
1791 			rate_flags = IEEE80211_TX_RC_VHT_MCS;
1792 			if ((vht_known & IEEE80211_RADIOTAP_VHT_KNOWN_GI) &&
1793 			    (iterator.this_arg[2] &
1794 			     IEEE80211_RADIOTAP_VHT_FLAG_SGI))
1795 				rate_flags |= IEEE80211_TX_RC_SHORT_GI;
1796 			if (vht_known &
1797 			    IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH) {
1798 				if (iterator.this_arg[3] == 1)
1799 					rate_flags |=
1800 						IEEE80211_TX_RC_40_MHZ_WIDTH;
1801 				else if (iterator.this_arg[3] == 4)
1802 					rate_flags |=
1803 						IEEE80211_TX_RC_80_MHZ_WIDTH;
1804 				else if (iterator.this_arg[3] == 11)
1805 					rate_flags |=
1806 						IEEE80211_TX_RC_160_MHZ_WIDTH;
1807 			}
1808 
1809 			vht_mcs = iterator.this_arg[4] >> 4;
1810 			vht_nss = iterator.this_arg[4] & 0xF;
1811 			break;
1812 
1813 		/*
1814 		 * Please update the file
1815 		 * Documentation/networking/mac80211-injection.txt
1816 		 * when parsing new fields here.
1817 		 */
1818 
1819 		default:
1820 			break;
1821 		}
1822 	}
1823 
1824 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1825 		return false;
1826 
1827 	if (rate_found) {
1828 		info->control.flags |= IEEE80211_TX_CTRL_RATE_INJECT;
1829 
1830 		for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
1831 			info->control.rates[i].idx = -1;
1832 			info->control.rates[i].flags = 0;
1833 			info->control.rates[i].count = 0;
1834 		}
1835 
1836 		if (rate_flags & IEEE80211_TX_RC_MCS) {
1837 			info->control.rates[0].idx = rate;
1838 		} else if (rate_flags & IEEE80211_TX_RC_VHT_MCS) {
1839 			ieee80211_rate_set_vht(info->control.rates, vht_mcs,
1840 					       vht_nss);
1841 		} else {
1842 			for (i = 0; i < sband->n_bitrates; i++) {
1843 				if (rate * 5 != sband->bitrates[i].bitrate)
1844 					continue;
1845 
1846 				info->control.rates[0].idx = i;
1847 				break;
1848 			}
1849 		}
1850 
1851 		if (info->control.rates[0].idx < 0)
1852 			info->control.flags &= ~IEEE80211_TX_CTRL_RATE_INJECT;
1853 
1854 		info->control.rates[0].flags = rate_flags;
1855 		info->control.rates[0].count = min_t(u8, rate_retries + 1,
1856 						     local->hw.max_rate_tries);
1857 	}
1858 
1859 	/*
1860 	 * remove the radiotap header
1861 	 * iterator->_max_length was sanity-checked against
1862 	 * skb->len by iterator init
1863 	 */
1864 	skb_pull(skb, iterator._max_length);
1865 
1866 	return true;
1867 }
1868 
1869 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1870 					 struct net_device *dev)
1871 {
1872 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1873 	struct ieee80211_chanctx_conf *chanctx_conf;
1874 	struct ieee80211_radiotap_header *prthdr =
1875 		(struct ieee80211_radiotap_header *)skb->data;
1876 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1877 	struct ieee80211_hdr *hdr;
1878 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1879 	struct cfg80211_chan_def *chandef;
1880 	u16 len_rthdr;
1881 	int hdrlen;
1882 
1883 	/* check for not even having the fixed radiotap header part */
1884 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1885 		goto fail; /* too short to be possibly valid */
1886 
1887 	/* is it a header version we can trust to find length from? */
1888 	if (unlikely(prthdr->it_version))
1889 		goto fail; /* only version 0 is supported */
1890 
1891 	/* then there must be a radiotap header with a length we can use */
1892 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1893 
1894 	/* does the skb contain enough to deliver on the alleged length? */
1895 	if (unlikely(skb->len < len_rthdr))
1896 		goto fail; /* skb too short for claimed rt header extent */
1897 
1898 	/*
1899 	 * fix up the pointers accounting for the radiotap
1900 	 * header still being in there.  We are being given
1901 	 * a precooked IEEE80211 header so no need for
1902 	 * normal processing
1903 	 */
1904 	skb_set_mac_header(skb, len_rthdr);
1905 	/*
1906 	 * these are just fixed to the end of the rt area since we
1907 	 * don't have any better information and at this point, nobody cares
1908 	 */
1909 	skb_set_network_header(skb, len_rthdr);
1910 	skb_set_transport_header(skb, len_rthdr);
1911 
1912 	if (skb->len < len_rthdr + 2)
1913 		goto fail;
1914 
1915 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1916 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1917 
1918 	if (skb->len < len_rthdr + hdrlen)
1919 		goto fail;
1920 
1921 	/*
1922 	 * Initialize skb->protocol if the injected frame is a data frame
1923 	 * carrying a rfc1042 header
1924 	 */
1925 	if (ieee80211_is_data(hdr->frame_control) &&
1926 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1927 		u8 *payload = (u8 *)hdr + hdrlen;
1928 
1929 		if (ether_addr_equal(payload, rfc1042_header))
1930 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1931 						    payload[7]);
1932 	}
1933 
1934 	memset(info, 0, sizeof(*info));
1935 
1936 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1937 		      IEEE80211_TX_CTL_INJECTED;
1938 
1939 	rcu_read_lock();
1940 
1941 	/*
1942 	 * We process outgoing injected frames that have a local address
1943 	 * we handle as though they are non-injected frames.
1944 	 * This code here isn't entirely correct, the local MAC address
1945 	 * isn't always enough to find the interface to use; for proper
1946 	 * VLAN/WDS support we will need a different mechanism (which
1947 	 * likely isn't going to be monitor interfaces).
1948 	 */
1949 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1950 
1951 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1952 		if (!ieee80211_sdata_running(tmp_sdata))
1953 			continue;
1954 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1955 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1956 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1957 			continue;
1958 		if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
1959 			sdata = tmp_sdata;
1960 			break;
1961 		}
1962 	}
1963 
1964 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1965 	if (!chanctx_conf) {
1966 		tmp_sdata = rcu_dereference(local->monitor_sdata);
1967 		if (tmp_sdata)
1968 			chanctx_conf =
1969 				rcu_dereference(tmp_sdata->vif.chanctx_conf);
1970 	}
1971 
1972 	if (chanctx_conf)
1973 		chandef = &chanctx_conf->def;
1974 	else if (!local->use_chanctx)
1975 		chandef = &local->_oper_chandef;
1976 	else
1977 		goto fail_rcu;
1978 
1979 	/*
1980 	 * Frame injection is not allowed if beaconing is not allowed
1981 	 * or if we need radar detection. Beaconing is usually not allowed when
1982 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1983 	 * Passive scan is also used in world regulatory domains where
1984 	 * your country is not known and as such it should be treated as
1985 	 * NO TX unless the channel is explicitly allowed in which case
1986 	 * your current regulatory domain would not have the passive scan
1987 	 * flag.
1988 	 *
1989 	 * Since AP mode uses monitor interfaces to inject/TX management
1990 	 * frames we can make AP mode the exception to this rule once it
1991 	 * supports radar detection as its implementation can deal with
1992 	 * radar detection by itself. We can do that later by adding a
1993 	 * monitor flag interfaces used for AP support.
1994 	 */
1995 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, chandef,
1996 				     sdata->vif.type))
1997 		goto fail_rcu;
1998 
1999 	info->band = chandef->chan->band;
2000 
2001 	/* process and remove the injection radiotap header */
2002 	if (!ieee80211_parse_tx_radiotap(local, skb))
2003 		goto fail_rcu;
2004 
2005 	ieee80211_xmit(sdata, NULL, skb);
2006 	rcu_read_unlock();
2007 
2008 	return NETDEV_TX_OK;
2009 
2010 fail_rcu:
2011 	rcu_read_unlock();
2012 fail:
2013 	dev_kfree_skb(skb);
2014 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
2015 }
2016 
2017 static inline bool ieee80211_is_tdls_setup(struct sk_buff *skb)
2018 {
2019 	u16 ethertype = (skb->data[12] << 8) | skb->data[13];
2020 
2021 	return ethertype == ETH_P_TDLS &&
2022 	       skb->len > 14 &&
2023 	       skb->data[14] == WLAN_TDLS_SNAP_RFTYPE;
2024 }
2025 
2026 static int ieee80211_lookup_ra_sta(struct ieee80211_sub_if_data *sdata,
2027 				   struct sk_buff *skb,
2028 				   struct sta_info **sta_out)
2029 {
2030 	struct sta_info *sta;
2031 
2032 	switch (sdata->vif.type) {
2033 	case NL80211_IFTYPE_AP_VLAN:
2034 		sta = rcu_dereference(sdata->u.vlan.sta);
2035 		if (sta) {
2036 			*sta_out = sta;
2037 			return 0;
2038 		} else if (sdata->wdev.use_4addr) {
2039 			return -ENOLINK;
2040 		}
2041 		/* fall through */
2042 	case NL80211_IFTYPE_AP:
2043 	case NL80211_IFTYPE_OCB:
2044 	case NL80211_IFTYPE_ADHOC:
2045 		if (is_multicast_ether_addr(skb->data)) {
2046 			*sta_out = ERR_PTR(-ENOENT);
2047 			return 0;
2048 		}
2049 		sta = sta_info_get_bss(sdata, skb->data);
2050 		break;
2051 	case NL80211_IFTYPE_WDS:
2052 		sta = sta_info_get(sdata, sdata->u.wds.remote_addr);
2053 		break;
2054 #ifdef CONFIG_MAC80211_MESH
2055 	case NL80211_IFTYPE_MESH_POINT:
2056 		/* determined much later */
2057 		*sta_out = NULL;
2058 		return 0;
2059 #endif
2060 	case NL80211_IFTYPE_STATION:
2061 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
2062 			sta = sta_info_get(sdata, skb->data);
2063 			if (sta) {
2064 				bool tdls_peer, tdls_auth;
2065 
2066 				tdls_peer = test_sta_flag(sta,
2067 							  WLAN_STA_TDLS_PEER);
2068 				tdls_auth = test_sta_flag(sta,
2069 						WLAN_STA_TDLS_PEER_AUTH);
2070 
2071 				if (tdls_peer && tdls_auth) {
2072 					*sta_out = sta;
2073 					return 0;
2074 				}
2075 
2076 				/*
2077 				 * TDLS link during setup - throw out frames to
2078 				 * peer. Allow TDLS-setup frames to unauthorized
2079 				 * peers for the special case of a link teardown
2080 				 * after a TDLS sta is removed due to being
2081 				 * unreachable.
2082 				 */
2083 				if (tdls_peer && !tdls_auth &&
2084 				    !ieee80211_is_tdls_setup(skb))
2085 					return -EINVAL;
2086 			}
2087 
2088 		}
2089 
2090 		sta = sta_info_get(sdata, sdata->u.mgd.bssid);
2091 		if (!sta)
2092 			return -ENOLINK;
2093 		break;
2094 	default:
2095 		return -EINVAL;
2096 	}
2097 
2098 	*sta_out = sta ?: ERR_PTR(-ENOENT);
2099 	return 0;
2100 }
2101 
2102 /**
2103  * ieee80211_build_hdr - build 802.11 header in the given frame
2104  * @sdata: virtual interface to build the header for
2105  * @skb: the skb to build the header in
2106  * @info_flags: skb flags to set
2107  *
2108  * This function takes the skb with 802.3 header and reformats the header to
2109  * the appropriate IEEE 802.11 header based on which interface the packet is
2110  * being transmitted on.
2111  *
2112  * Note that this function also takes care of the TX status request and
2113  * potential unsharing of the SKB - this needs to be interleaved with the
2114  * header building.
2115  *
2116  * The function requires the read-side RCU lock held
2117  *
2118  * Returns: the (possibly reallocated) skb or an ERR_PTR() code
2119  */
2120 static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
2121 					   struct sk_buff *skb, u32 info_flags,
2122 					   struct sta_info *sta)
2123 {
2124 	struct ieee80211_local *local = sdata->local;
2125 	struct ieee80211_tx_info *info;
2126 	int head_need;
2127 	u16 ethertype, hdrlen,  meshhdrlen = 0;
2128 	__le16 fc;
2129 	struct ieee80211_hdr hdr;
2130 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
2131 	struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
2132 	const u8 *encaps_data;
2133 	int encaps_len, skip_header_bytes;
2134 	int nh_pos, h_pos;
2135 	bool wme_sta = false, authorized = false;
2136 	bool tdls_peer;
2137 	bool multicast;
2138 	u16 info_id = 0;
2139 	struct ieee80211_chanctx_conf *chanctx_conf;
2140 	struct ieee80211_sub_if_data *ap_sdata;
2141 	enum nl80211_band band;
2142 	int ret;
2143 
2144 	if (IS_ERR(sta))
2145 		sta = NULL;
2146 
2147 	/* convert Ethernet header to proper 802.11 header (based on
2148 	 * operation mode) */
2149 	ethertype = (skb->data[12] << 8) | skb->data[13];
2150 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
2151 
2152 	switch (sdata->vif.type) {
2153 	case NL80211_IFTYPE_AP_VLAN:
2154 		if (sdata->wdev.use_4addr) {
2155 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
2156 			/* RA TA DA SA */
2157 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
2158 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2159 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2160 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2161 			hdrlen = 30;
2162 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
2163 			wme_sta = sta->sta.wme;
2164 		}
2165 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2166 					u.ap);
2167 		chanctx_conf = rcu_dereference(ap_sdata->vif.chanctx_conf);
2168 		if (!chanctx_conf) {
2169 			ret = -ENOTCONN;
2170 			goto free;
2171 		}
2172 		band = chanctx_conf->def.chan->band;
2173 		if (sdata->wdev.use_4addr)
2174 			break;
2175 		/* fall through */
2176 	case NL80211_IFTYPE_AP:
2177 		if (sdata->vif.type == NL80211_IFTYPE_AP)
2178 			chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2179 		if (!chanctx_conf) {
2180 			ret = -ENOTCONN;
2181 			goto free;
2182 		}
2183 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
2184 		/* DA BSSID SA */
2185 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2186 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2187 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
2188 		hdrlen = 24;
2189 		band = chanctx_conf->def.chan->band;
2190 		break;
2191 	case NL80211_IFTYPE_WDS:
2192 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
2193 		/* RA TA DA SA */
2194 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
2195 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2196 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
2197 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2198 		hdrlen = 30;
2199 		/*
2200 		 * This is the exception! WDS style interfaces are prohibited
2201 		 * when channel contexts are in used so this must be valid
2202 		 */
2203 		band = local->hw.conf.chandef.chan->band;
2204 		break;
2205 #ifdef CONFIG_MAC80211_MESH
2206 	case NL80211_IFTYPE_MESH_POINT:
2207 		if (!is_multicast_ether_addr(skb->data)) {
2208 			struct sta_info *next_hop;
2209 			bool mpp_lookup = true;
2210 
2211 			mpath = mesh_path_lookup(sdata, skb->data);
2212 			if (mpath) {
2213 				mpp_lookup = false;
2214 				next_hop = rcu_dereference(mpath->next_hop);
2215 				if (!next_hop ||
2216 				    !(mpath->flags & (MESH_PATH_ACTIVE |
2217 						      MESH_PATH_RESOLVING)))
2218 					mpp_lookup = true;
2219 			}
2220 
2221 			if (mpp_lookup) {
2222 				mppath = mpp_path_lookup(sdata, skb->data);
2223 				if (mppath)
2224 					mppath->exp_time = jiffies;
2225 			}
2226 
2227 			if (mppath && mpath)
2228 				mesh_path_del(sdata, mpath->dst);
2229 		}
2230 
2231 		/*
2232 		 * Use address extension if it is a packet from
2233 		 * another interface or if we know the destination
2234 		 * is being proxied by a portal (i.e. portal address
2235 		 * differs from proxied address)
2236 		 */
2237 		if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
2238 		    !(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
2239 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
2240 					skb->data, skb->data + ETH_ALEN);
2241 			meshhdrlen = ieee80211_new_mesh_header(sdata, &mesh_hdr,
2242 							       NULL, NULL);
2243 		} else {
2244 			/* DS -> MBSS (802.11-2012 13.11.3.3).
2245 			 * For unicast with unknown forwarding information,
2246 			 * destination might be in the MBSS or if that fails
2247 			 * forwarded to another mesh gate. In either case
2248 			 * resolution will be handled in ieee80211_xmit(), so
2249 			 * leave the original DA. This also works for mcast */
2250 			const u8 *mesh_da = skb->data;
2251 
2252 			if (mppath)
2253 				mesh_da = mppath->mpp;
2254 			else if (mpath)
2255 				mesh_da = mpath->dst;
2256 
2257 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
2258 					mesh_da, sdata->vif.addr);
2259 			if (is_multicast_ether_addr(mesh_da))
2260 				/* DA TA mSA AE:SA */
2261 				meshhdrlen = ieee80211_new_mesh_header(
2262 						sdata, &mesh_hdr,
2263 						skb->data + ETH_ALEN, NULL);
2264 			else
2265 				/* RA TA mDA mSA AE:DA SA */
2266 				meshhdrlen = ieee80211_new_mesh_header(
2267 						sdata, &mesh_hdr, skb->data,
2268 						skb->data + ETH_ALEN);
2269 
2270 		}
2271 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2272 		if (!chanctx_conf) {
2273 			ret = -ENOTCONN;
2274 			goto free;
2275 		}
2276 		band = chanctx_conf->def.chan->band;
2277 		break;
2278 #endif
2279 	case NL80211_IFTYPE_STATION:
2280 		/* we already did checks when looking up the RA STA */
2281 		tdls_peer = test_sta_flag(sta, WLAN_STA_TDLS_PEER);
2282 
2283 		if (tdls_peer) {
2284 			/* DA SA BSSID */
2285 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
2286 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2287 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
2288 			hdrlen = 24;
2289 		}  else if (sdata->u.mgd.use_4addr &&
2290 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
2291 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2292 					  IEEE80211_FCTL_TODS);
2293 			/* RA TA DA SA */
2294 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
2295 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2296 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2297 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2298 			hdrlen = 30;
2299 		} else {
2300 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
2301 			/* BSSID SA DA */
2302 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
2303 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2304 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2305 			hdrlen = 24;
2306 		}
2307 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2308 		if (!chanctx_conf) {
2309 			ret = -ENOTCONN;
2310 			goto free;
2311 		}
2312 		band = chanctx_conf->def.chan->band;
2313 		break;
2314 	case NL80211_IFTYPE_OCB:
2315 		/* DA SA BSSID */
2316 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2317 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2318 		eth_broadcast_addr(hdr.addr3);
2319 		hdrlen = 24;
2320 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2321 		if (!chanctx_conf) {
2322 			ret = -ENOTCONN;
2323 			goto free;
2324 		}
2325 		band = chanctx_conf->def.chan->band;
2326 		break;
2327 	case NL80211_IFTYPE_ADHOC:
2328 		/* DA SA BSSID */
2329 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2330 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2331 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
2332 		hdrlen = 24;
2333 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2334 		if (!chanctx_conf) {
2335 			ret = -ENOTCONN;
2336 			goto free;
2337 		}
2338 		band = chanctx_conf->def.chan->band;
2339 		break;
2340 	default:
2341 		ret = -EINVAL;
2342 		goto free;
2343 	}
2344 
2345 	multicast = is_multicast_ether_addr(hdr.addr1);
2346 
2347 	/* sta is always NULL for mesh */
2348 	if (sta) {
2349 		authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
2350 		wme_sta = sta->sta.wme;
2351 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2352 		/* For mesh, the use of the QoS header is mandatory */
2353 		wme_sta = true;
2354 	}
2355 
2356 	/* receiver does QoS (which also means we do) use it */
2357 	if (wme_sta) {
2358 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2359 		hdrlen += 2;
2360 	}
2361 
2362 	/*
2363 	 * Drop unicast frames to unauthorised stations unless they are
2364 	 * EAPOL frames from the local station.
2365 	 */
2366 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
2367 		     (sdata->vif.type != NL80211_IFTYPE_OCB) &&
2368 		     !multicast && !authorized &&
2369 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
2370 		      !ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
2371 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
2372 		net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
2373 				    sdata->name, hdr.addr1);
2374 #endif
2375 
2376 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
2377 
2378 		ret = -EPERM;
2379 		goto free;
2380 	}
2381 
2382 	if (unlikely(!multicast && skb->sk &&
2383 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
2384 		struct sk_buff *ack_skb = skb_clone_sk(skb);
2385 
2386 		if (ack_skb) {
2387 			unsigned long flags;
2388 			int id;
2389 
2390 			spin_lock_irqsave(&local->ack_status_lock, flags);
2391 			id = idr_alloc(&local->ack_status_frames, ack_skb,
2392 				       1, 0x10000, GFP_ATOMIC);
2393 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
2394 
2395 			if (id >= 0) {
2396 				info_id = id;
2397 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
2398 			} else {
2399 				kfree_skb(ack_skb);
2400 			}
2401 		}
2402 	}
2403 
2404 	/*
2405 	 * If the skb is shared we need to obtain our own copy.
2406 	 */
2407 	if (skb_shared(skb)) {
2408 		struct sk_buff *tmp_skb = skb;
2409 
2410 		/* can't happen -- skb is a clone if info_id != 0 */
2411 		WARN_ON(info_id);
2412 
2413 		skb = skb_clone(skb, GFP_ATOMIC);
2414 		kfree_skb(tmp_skb);
2415 
2416 		if (!skb) {
2417 			ret = -ENOMEM;
2418 			goto free;
2419 		}
2420 	}
2421 
2422 	hdr.frame_control = fc;
2423 	hdr.duration_id = 0;
2424 	hdr.seq_ctrl = 0;
2425 
2426 	skip_header_bytes = ETH_HLEN;
2427 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2428 		encaps_data = bridge_tunnel_header;
2429 		encaps_len = sizeof(bridge_tunnel_header);
2430 		skip_header_bytes -= 2;
2431 	} else if (ethertype >= ETH_P_802_3_MIN) {
2432 		encaps_data = rfc1042_header;
2433 		encaps_len = sizeof(rfc1042_header);
2434 		skip_header_bytes -= 2;
2435 	} else {
2436 		encaps_data = NULL;
2437 		encaps_len = 0;
2438 	}
2439 
2440 	nh_pos = skb_network_header(skb) - skb->data;
2441 	h_pos = skb_transport_header(skb) - skb->data;
2442 
2443 	skb_pull(skb, skip_header_bytes);
2444 	nh_pos -= skip_header_bytes;
2445 	h_pos -= skip_header_bytes;
2446 
2447 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2448 
2449 	/*
2450 	 * So we need to modify the skb header and hence need a copy of
2451 	 * that. The head_need variable above doesn't, so far, include
2452 	 * the needed header space that we don't need right away. If we
2453 	 * can, then we don't reallocate right now but only after the
2454 	 * frame arrives at the master device (if it does...)
2455 	 *
2456 	 * If we cannot, however, then we will reallocate to include all
2457 	 * the ever needed space. Also, if we need to reallocate it anyway,
2458 	 * make it big enough for everything we may ever need.
2459 	 */
2460 
2461 	if (head_need > 0 || skb_cloned(skb)) {
2462 		head_need += sdata->encrypt_headroom;
2463 		head_need += local->tx_headroom;
2464 		head_need = max_t(int, 0, head_need);
2465 		if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
2466 			ieee80211_free_txskb(&local->hw, skb);
2467 			skb = NULL;
2468 			return ERR_PTR(-ENOMEM);
2469 		}
2470 	}
2471 
2472 	if (encaps_data) {
2473 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2474 		nh_pos += encaps_len;
2475 		h_pos += encaps_len;
2476 	}
2477 
2478 #ifdef CONFIG_MAC80211_MESH
2479 	if (meshhdrlen > 0) {
2480 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2481 		nh_pos += meshhdrlen;
2482 		h_pos += meshhdrlen;
2483 	}
2484 #endif
2485 
2486 	if (ieee80211_is_data_qos(fc)) {
2487 		__le16 *qos_control;
2488 
2489 		qos_control = (__le16 *) skb_push(skb, 2);
2490 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2491 		/*
2492 		 * Maybe we could actually set some fields here, for now just
2493 		 * initialise to zero to indicate no special operation.
2494 		 */
2495 		*qos_control = 0;
2496 	} else
2497 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2498 
2499 	nh_pos += hdrlen;
2500 	h_pos += hdrlen;
2501 
2502 	/* Update skb pointers to various headers since this modified frame
2503 	 * is going to go through Linux networking code that may potentially
2504 	 * need things like pointer to IP header. */
2505 	skb_reset_mac_header(skb);
2506 	skb_set_network_header(skb, nh_pos);
2507 	skb_set_transport_header(skb, h_pos);
2508 
2509 	info = IEEE80211_SKB_CB(skb);
2510 	memset(info, 0, sizeof(*info));
2511 
2512 	info->flags = info_flags;
2513 	info->ack_frame_id = info_id;
2514 	info->band = band;
2515 
2516 	return skb;
2517  free:
2518 	kfree_skb(skb);
2519 	return ERR_PTR(ret);
2520 }
2521 
2522 /*
2523  * fast-xmit overview
2524  *
2525  * The core idea of this fast-xmit is to remove per-packet checks by checking
2526  * them out of band. ieee80211_check_fast_xmit() implements the out-of-band
2527  * checks that are needed to get the sta->fast_tx pointer assigned, after which
2528  * much less work can be done per packet. For example, fragmentation must be
2529  * disabled or the fast_tx pointer will not be set. All the conditions are seen
2530  * in the code here.
2531  *
2532  * Once assigned, the fast_tx data structure also caches the per-packet 802.11
2533  * header and other data to aid packet processing in ieee80211_xmit_fast().
2534  *
2535  * The most difficult part of this is that when any of these assumptions
2536  * change, an external trigger (i.e. a call to ieee80211_clear_fast_xmit(),
2537  * ieee80211_check_fast_xmit() or friends) is required to reset the data,
2538  * since the per-packet code no longer checks the conditions. This is reflected
2539  * by the calls to these functions throughout the rest of the code, and must be
2540  * maintained if any of the TX path checks change.
2541  */
2542 
2543 void ieee80211_check_fast_xmit(struct sta_info *sta)
2544 {
2545 	struct ieee80211_fast_tx build = {}, *fast_tx = NULL, *old;
2546 	struct ieee80211_local *local = sta->local;
2547 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2548 	struct ieee80211_hdr *hdr = (void *)build.hdr;
2549 	struct ieee80211_chanctx_conf *chanctx_conf;
2550 	__le16 fc;
2551 
2552 	if (!ieee80211_hw_check(&local->hw, SUPPORT_FAST_XMIT))
2553 		return;
2554 
2555 	/* Locking here protects both the pointer itself, and against concurrent
2556 	 * invocations winning data access races to, e.g., the key pointer that
2557 	 * is used.
2558 	 * Without it, the invocation of this function right after the key
2559 	 * pointer changes wouldn't be sufficient, as another CPU could access
2560 	 * the pointer, then stall, and then do the cache update after the CPU
2561 	 * that invalidated the key.
2562 	 * With the locking, such scenarios cannot happen as the check for the
2563 	 * key and the fast-tx assignment are done atomically, so the CPU that
2564 	 * modifies the key will either wait or other one will see the key
2565 	 * cleared/changed already.
2566 	 */
2567 	spin_lock_bh(&sta->lock);
2568 	if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
2569 	    !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
2570 	    sdata->vif.type == NL80211_IFTYPE_STATION)
2571 		goto out;
2572 
2573 	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
2574 		goto out;
2575 
2576 	if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
2577 	    test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
2578 	    test_sta_flag(sta, WLAN_STA_PS_DELIVER) ||
2579 	    test_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT))
2580 		goto out;
2581 
2582 	if (sdata->noack_map)
2583 		goto out;
2584 
2585 	/* fast-xmit doesn't handle fragmentation at all */
2586 	if (local->hw.wiphy->frag_threshold != (u32)-1 &&
2587 	    !local->ops->set_frag_threshold)
2588 		goto out;
2589 
2590 	rcu_read_lock();
2591 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2592 	if (!chanctx_conf) {
2593 		rcu_read_unlock();
2594 		goto out;
2595 	}
2596 	build.band = chanctx_conf->def.chan->band;
2597 	rcu_read_unlock();
2598 
2599 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
2600 
2601 	switch (sdata->vif.type) {
2602 	case NL80211_IFTYPE_ADHOC:
2603 		/* DA SA BSSID */
2604 		build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2605 		build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2606 		memcpy(hdr->addr3, sdata->u.ibss.bssid, ETH_ALEN);
2607 		build.hdr_len = 24;
2608 		break;
2609 	case NL80211_IFTYPE_STATION:
2610 		if (test_sta_flag(sta, WLAN_STA_TDLS_PEER)) {
2611 			/* DA SA BSSID */
2612 			build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2613 			build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2614 			memcpy(hdr->addr3, sdata->u.mgd.bssid, ETH_ALEN);
2615 			build.hdr_len = 24;
2616 			break;
2617 		}
2618 
2619 		if (sdata->u.mgd.use_4addr) {
2620 			/* non-regular ethertype cannot use the fastpath */
2621 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2622 					  IEEE80211_FCTL_TODS);
2623 			/* RA TA DA SA */
2624 			memcpy(hdr->addr1, sdata->u.mgd.bssid, ETH_ALEN);
2625 			memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2626 			build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2627 			build.sa_offs = offsetof(struct ieee80211_hdr, addr4);
2628 			build.hdr_len = 30;
2629 			break;
2630 		}
2631 		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
2632 		/* BSSID SA DA */
2633 		memcpy(hdr->addr1, sdata->u.mgd.bssid, ETH_ALEN);
2634 		build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2635 		build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2636 		build.hdr_len = 24;
2637 		break;
2638 	case NL80211_IFTYPE_AP_VLAN:
2639 		if (sdata->wdev.use_4addr) {
2640 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2641 					  IEEE80211_FCTL_TODS);
2642 			/* RA TA DA SA */
2643 			memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
2644 			memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2645 			build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2646 			build.sa_offs = offsetof(struct ieee80211_hdr, addr4);
2647 			build.hdr_len = 30;
2648 			break;
2649 		}
2650 		/* fall through */
2651 	case NL80211_IFTYPE_AP:
2652 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
2653 		/* DA BSSID SA */
2654 		build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2655 		memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2656 		build.sa_offs = offsetof(struct ieee80211_hdr, addr3);
2657 		build.hdr_len = 24;
2658 		break;
2659 	default:
2660 		/* not handled on fast-xmit */
2661 		goto out;
2662 	}
2663 
2664 	if (sta->sta.wme) {
2665 		build.hdr_len += 2;
2666 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2667 	}
2668 
2669 	/* We store the key here so there's no point in using rcu_dereference()
2670 	 * but that's fine because the code that changes the pointers will call
2671 	 * this function after doing so. For a single CPU that would be enough,
2672 	 * for multiple see the comment above.
2673 	 */
2674 	build.key = rcu_access_pointer(sta->ptk[sta->ptk_idx]);
2675 	if (!build.key)
2676 		build.key = rcu_access_pointer(sdata->default_unicast_key);
2677 	if (build.key) {
2678 		bool gen_iv, iv_spc, mmic;
2679 
2680 		gen_iv = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
2681 		iv_spc = build.key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
2682 		mmic = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC;
2683 
2684 		/* don't handle software crypto */
2685 		if (!(build.key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
2686 			goto out;
2687 
2688 		switch (build.key->conf.cipher) {
2689 		case WLAN_CIPHER_SUITE_CCMP:
2690 		case WLAN_CIPHER_SUITE_CCMP_256:
2691 			/* add fixed key ID */
2692 			if (gen_iv) {
2693 				(build.hdr + build.hdr_len)[3] =
2694 					0x20 | (build.key->conf.keyidx << 6);
2695 				build.pn_offs = build.hdr_len;
2696 			}
2697 			if (gen_iv || iv_spc)
2698 				build.hdr_len += IEEE80211_CCMP_HDR_LEN;
2699 			break;
2700 		case WLAN_CIPHER_SUITE_GCMP:
2701 		case WLAN_CIPHER_SUITE_GCMP_256:
2702 			/* add fixed key ID */
2703 			if (gen_iv) {
2704 				(build.hdr + build.hdr_len)[3] =
2705 					0x20 | (build.key->conf.keyidx << 6);
2706 				build.pn_offs = build.hdr_len;
2707 			}
2708 			if (gen_iv || iv_spc)
2709 				build.hdr_len += IEEE80211_GCMP_HDR_LEN;
2710 			break;
2711 		case WLAN_CIPHER_SUITE_TKIP:
2712 			/* cannot handle MMIC or IV generation in xmit-fast */
2713 			if (mmic || gen_iv)
2714 				goto out;
2715 			if (iv_spc)
2716 				build.hdr_len += IEEE80211_TKIP_IV_LEN;
2717 			break;
2718 		case WLAN_CIPHER_SUITE_WEP40:
2719 		case WLAN_CIPHER_SUITE_WEP104:
2720 			/* cannot handle IV generation in fast-xmit */
2721 			if (gen_iv)
2722 				goto out;
2723 			if (iv_spc)
2724 				build.hdr_len += IEEE80211_WEP_IV_LEN;
2725 			break;
2726 		case WLAN_CIPHER_SUITE_AES_CMAC:
2727 		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
2728 		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
2729 		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
2730 			WARN(1,
2731 			     "management cipher suite 0x%x enabled for data\n",
2732 			     build.key->conf.cipher);
2733 			goto out;
2734 		default:
2735 			/* we don't know how to generate IVs for this at all */
2736 			if (WARN_ON(gen_iv))
2737 				goto out;
2738 			/* pure hardware keys are OK, of course */
2739 			if (!(build.key->flags & KEY_FLAG_CIPHER_SCHEME))
2740 				break;
2741 			/* cipher scheme might require space allocation */
2742 			if (iv_spc &&
2743 			    build.key->conf.iv_len > IEEE80211_FAST_XMIT_MAX_IV)
2744 				goto out;
2745 			if (iv_spc)
2746 				build.hdr_len += build.key->conf.iv_len;
2747 		}
2748 
2749 		fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
2750 	}
2751 
2752 	hdr->frame_control = fc;
2753 
2754 	memcpy(build.hdr + build.hdr_len,
2755 	       rfc1042_header,  sizeof(rfc1042_header));
2756 	build.hdr_len += sizeof(rfc1042_header);
2757 
2758 	fast_tx = kmemdup(&build, sizeof(build), GFP_ATOMIC);
2759 	/* if the kmemdup fails, continue w/o fast_tx */
2760 	if (!fast_tx)
2761 		goto out;
2762 
2763  out:
2764 	/* we might have raced against another call to this function */
2765 	old = rcu_dereference_protected(sta->fast_tx,
2766 					lockdep_is_held(&sta->lock));
2767 	rcu_assign_pointer(sta->fast_tx, fast_tx);
2768 	if (old)
2769 		kfree_rcu(old, rcu_head);
2770 	spin_unlock_bh(&sta->lock);
2771 }
2772 
2773 void ieee80211_check_fast_xmit_all(struct ieee80211_local *local)
2774 {
2775 	struct sta_info *sta;
2776 
2777 	rcu_read_lock();
2778 	list_for_each_entry_rcu(sta, &local->sta_list, list)
2779 		ieee80211_check_fast_xmit(sta);
2780 	rcu_read_unlock();
2781 }
2782 
2783 void ieee80211_check_fast_xmit_iface(struct ieee80211_sub_if_data *sdata)
2784 {
2785 	struct ieee80211_local *local = sdata->local;
2786 	struct sta_info *sta;
2787 
2788 	rcu_read_lock();
2789 
2790 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
2791 		if (sdata != sta->sdata &&
2792 		    (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
2793 			continue;
2794 		ieee80211_check_fast_xmit(sta);
2795 	}
2796 
2797 	rcu_read_unlock();
2798 }
2799 
2800 void ieee80211_clear_fast_xmit(struct sta_info *sta)
2801 {
2802 	struct ieee80211_fast_tx *fast_tx;
2803 
2804 	spin_lock_bh(&sta->lock);
2805 	fast_tx = rcu_dereference_protected(sta->fast_tx,
2806 					    lockdep_is_held(&sta->lock));
2807 	RCU_INIT_POINTER(sta->fast_tx, NULL);
2808 	spin_unlock_bh(&sta->lock);
2809 
2810 	if (fast_tx)
2811 		kfree_rcu(fast_tx, rcu_head);
2812 }
2813 
2814 static bool ieee80211_amsdu_realloc_pad(struct ieee80211_local *local,
2815 					struct sk_buff *skb, int headroom,
2816 					int *subframe_len)
2817 {
2818 	int amsdu_len = *subframe_len + sizeof(struct ethhdr);
2819 	int padding = (4 - amsdu_len) & 3;
2820 
2821 	if (skb_headroom(skb) < headroom || skb_tailroom(skb) < padding) {
2822 		I802_DEBUG_INC(local->tx_expand_skb_head);
2823 
2824 		if (pskb_expand_head(skb, headroom, padding, GFP_ATOMIC)) {
2825 			wiphy_debug(local->hw.wiphy,
2826 				    "failed to reallocate TX buffer\n");
2827 			return false;
2828 		}
2829 	}
2830 
2831 	if (padding) {
2832 		*subframe_len += padding;
2833 		memset(skb_put(skb, padding), 0, padding);
2834 	}
2835 
2836 	return true;
2837 }
2838 
2839 static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata,
2840 					 struct ieee80211_fast_tx *fast_tx,
2841 					 struct sk_buff *skb)
2842 {
2843 	struct ieee80211_local *local = sdata->local;
2844 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2845 	struct ieee80211_hdr *hdr;
2846 	struct ethhdr amsdu_hdr;
2847 	int hdr_len = fast_tx->hdr_len - sizeof(rfc1042_header);
2848 	int subframe_len = skb->len - hdr_len;
2849 	void *data;
2850 	u8 *qc;
2851 
2852 	if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
2853 		return false;
2854 
2855 	if (info->control.flags & IEEE80211_TX_CTRL_AMSDU)
2856 		return true;
2857 
2858 	if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(amsdu_hdr),
2859 					 &subframe_len))
2860 		return false;
2861 
2862 	amsdu_hdr.h_proto = cpu_to_be16(subframe_len);
2863 	memcpy(amsdu_hdr.h_source, skb->data + fast_tx->sa_offs, ETH_ALEN);
2864 	memcpy(amsdu_hdr.h_dest, skb->data + fast_tx->da_offs, ETH_ALEN);
2865 
2866 	data = skb_push(skb, sizeof(amsdu_hdr));
2867 	memmove(data, data + sizeof(amsdu_hdr), hdr_len);
2868 	memcpy(data + hdr_len, &amsdu_hdr, sizeof(amsdu_hdr));
2869 
2870 	hdr = data;
2871 	qc = ieee80211_get_qos_ctl(hdr);
2872 	*qc |= IEEE80211_QOS_CTL_A_MSDU_PRESENT;
2873 
2874 	info->control.flags |= IEEE80211_TX_CTRL_AMSDU;
2875 
2876 	return true;
2877 }
2878 
2879 static bool ieee80211_amsdu_aggregate(struct ieee80211_sub_if_data *sdata,
2880 				      struct sta_info *sta,
2881 				      struct ieee80211_fast_tx *fast_tx,
2882 				      struct sk_buff *skb)
2883 {
2884 	struct ieee80211_local *local = sdata->local;
2885 	u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
2886 	struct ieee80211_txq *txq = sta->sta.txq[tid];
2887 	struct txq_info *txqi;
2888 	struct sk_buff **frag_tail, *head;
2889 	int subframe_len = skb->len - ETH_ALEN;
2890 	u8 max_subframes = sta->sta.max_amsdu_subframes;
2891 	int max_frags = local->hw.max_tx_fragments;
2892 	int max_amsdu_len = sta->sta.max_amsdu_len;
2893 	__be16 len;
2894 	void *data;
2895 	bool ret = false;
2896 	int n = 1, nfrags;
2897 
2898 	if (!ieee80211_hw_check(&local->hw, TX_AMSDU))
2899 		return false;
2900 
2901 	if (!txq)
2902 		return false;
2903 
2904 	txqi = to_txq_info(txq);
2905 	if (test_bit(IEEE80211_TXQ_NO_AMSDU, &txqi->flags))
2906 		return false;
2907 
2908 	if (sta->sta.max_rc_amsdu_len)
2909 		max_amsdu_len = min_t(int, max_amsdu_len,
2910 				      sta->sta.max_rc_amsdu_len);
2911 
2912 	spin_lock_bh(&txqi->queue.lock);
2913 
2914 	head = skb_peek_tail(&txqi->queue);
2915 	if (!head)
2916 		goto out;
2917 
2918 	if (skb->len + head->len > max_amsdu_len)
2919 		goto out;
2920 
2921 	if (!ieee80211_amsdu_prepare_head(sdata, fast_tx, head))
2922 		goto out;
2923 
2924 	nfrags = 1 + skb_shinfo(skb)->nr_frags;
2925 	nfrags += 1 + skb_shinfo(head)->nr_frags;
2926 	frag_tail = &skb_shinfo(head)->frag_list;
2927 	while (*frag_tail) {
2928 		nfrags += 1 + skb_shinfo(*frag_tail)->nr_frags;
2929 		frag_tail = &(*frag_tail)->next;
2930 		n++;
2931 	}
2932 
2933 	if (max_subframes && n > max_subframes)
2934 		goto out;
2935 
2936 	if (max_frags && nfrags > max_frags)
2937 		goto out;
2938 
2939 	if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(rfc1042_header) + 2,
2940 					 &subframe_len))
2941 		goto out;
2942 
2943 	ret = true;
2944 	data = skb_push(skb, ETH_ALEN + 2);
2945 	memmove(data, data + ETH_ALEN + 2, 2 * ETH_ALEN);
2946 
2947 	data += 2 * ETH_ALEN;
2948 	len = cpu_to_be16(subframe_len);
2949 	memcpy(data, &len, 2);
2950 	memcpy(data + 2, rfc1042_header, sizeof(rfc1042_header));
2951 
2952 	head->len += skb->len;
2953 	head->data_len += skb->len;
2954 	*frag_tail = skb;
2955 
2956 out:
2957 	spin_unlock_bh(&txqi->queue.lock);
2958 
2959 	return ret;
2960 }
2961 
2962 static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata,
2963 				struct net_device *dev, struct sta_info *sta,
2964 				struct ieee80211_fast_tx *fast_tx,
2965 				struct sk_buff *skb)
2966 {
2967 	struct ieee80211_local *local = sdata->local;
2968 	u16 ethertype = (skb->data[12] << 8) | skb->data[13];
2969 	int extra_head = fast_tx->hdr_len - (ETH_HLEN - 2);
2970 	int hw_headroom = sdata->local->hw.extra_tx_headroom;
2971 	struct ethhdr eth;
2972 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2973 	struct ieee80211_hdr *hdr = (void *)fast_tx->hdr;
2974 	struct ieee80211_tx_data tx;
2975 	ieee80211_tx_result r;
2976 	struct tid_ampdu_tx *tid_tx = NULL;
2977 	u8 tid = IEEE80211_NUM_TIDS;
2978 
2979 	/* control port protocol needs a lot of special handling */
2980 	if (cpu_to_be16(ethertype) == sdata->control_port_protocol)
2981 		return false;
2982 
2983 	/* only RFC 1042 SNAP */
2984 	if (ethertype < ETH_P_802_3_MIN)
2985 		return false;
2986 
2987 	/* don't handle TX status request here either */
2988 	if (skb->sk && skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)
2989 		return false;
2990 
2991 	if (hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) {
2992 		tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
2993 		tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
2994 		if (tid_tx) {
2995 			if (!test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state))
2996 				return false;
2997 			if (tid_tx->timeout)
2998 				tid_tx->last_tx = jiffies;
2999 		}
3000 	}
3001 
3002 	/* after this point (skb is modified) we cannot return false */
3003 
3004 	if (skb_shared(skb)) {
3005 		struct sk_buff *tmp_skb = skb;
3006 
3007 		skb = skb_clone(skb, GFP_ATOMIC);
3008 		kfree_skb(tmp_skb);
3009 
3010 		if (!skb)
3011 			return true;
3012 	}
3013 
3014 	ieee80211_tx_stats(dev, skb->len + extra_head);
3015 
3016 	if ((hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) &&
3017 	    ieee80211_amsdu_aggregate(sdata, sta, fast_tx, skb))
3018 		return true;
3019 
3020 	/* will not be crypto-handled beyond what we do here, so use false
3021 	 * as the may-encrypt argument for the resize to not account for
3022 	 * more room than we already have in 'extra_head'
3023 	 */
3024 	if (unlikely(ieee80211_skb_resize(sdata, skb,
3025 					  max_t(int, extra_head + hw_headroom -
3026 						     skb_headroom(skb), 0),
3027 					  false))) {
3028 		kfree_skb(skb);
3029 		return true;
3030 	}
3031 
3032 	memcpy(&eth, skb->data, ETH_HLEN - 2);
3033 	hdr = (void *)skb_push(skb, extra_head);
3034 	memcpy(skb->data, fast_tx->hdr, fast_tx->hdr_len);
3035 	memcpy(skb->data + fast_tx->da_offs, eth.h_dest, ETH_ALEN);
3036 	memcpy(skb->data + fast_tx->sa_offs, eth.h_source, ETH_ALEN);
3037 
3038 	memset(info, 0, sizeof(*info));
3039 	info->band = fast_tx->band;
3040 	info->control.vif = &sdata->vif;
3041 	info->flags = IEEE80211_TX_CTL_FIRST_FRAGMENT |
3042 		      IEEE80211_TX_CTL_DONTFRAG |
3043 		      (tid_tx ? IEEE80211_TX_CTL_AMPDU : 0);
3044 
3045 	if (hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) {
3046 		*ieee80211_get_qos_ctl(hdr) = tid;
3047 		if (!sta->sta.txq[0])
3048 			hdr->seq_ctrl = ieee80211_tx_next_seq(sta, tid);
3049 	} else {
3050 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
3051 		hdr->seq_ctrl = cpu_to_le16(sdata->sequence_number);
3052 		sdata->sequence_number += 0x10;
3053 	}
3054 
3055 	if (skb_shinfo(skb)->gso_size)
3056 		sta->tx_stats.msdu[tid] +=
3057 			DIV_ROUND_UP(skb->len, skb_shinfo(skb)->gso_size);
3058 	else
3059 		sta->tx_stats.msdu[tid]++;
3060 
3061 	info->hw_queue = sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
3062 
3063 	__skb_queue_head_init(&tx.skbs);
3064 
3065 	tx.flags = IEEE80211_TX_UNICAST;
3066 	tx.local = local;
3067 	tx.sdata = sdata;
3068 	tx.sta = sta;
3069 	tx.key = fast_tx->key;
3070 
3071 	if (fast_tx->key)
3072 		info->control.hw_key = &fast_tx->key->conf;
3073 
3074 	if (!ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
3075 		tx.skb = skb;
3076 		r = ieee80211_tx_h_rate_ctrl(&tx);
3077 		skb = tx.skb;
3078 		tx.skb = NULL;
3079 
3080 		if (r != TX_CONTINUE) {
3081 			if (r != TX_QUEUED)
3082 				kfree_skb(skb);
3083 			return true;
3084 		}
3085 	}
3086 
3087 	/* statistics normally done by ieee80211_tx_h_stats (but that
3088 	 * has to consider fragmentation, so is more complex)
3089 	 */
3090 	sta->tx_stats.bytes[skb_get_queue_mapping(skb)] += skb->len;
3091 	sta->tx_stats.packets[skb_get_queue_mapping(skb)]++;
3092 
3093 	if (fast_tx->pn_offs) {
3094 		u64 pn;
3095 		u8 *crypto_hdr = skb->data + fast_tx->pn_offs;
3096 
3097 		switch (fast_tx->key->conf.cipher) {
3098 		case WLAN_CIPHER_SUITE_CCMP:
3099 		case WLAN_CIPHER_SUITE_CCMP_256:
3100 		case WLAN_CIPHER_SUITE_GCMP:
3101 		case WLAN_CIPHER_SUITE_GCMP_256:
3102 			pn = atomic64_inc_return(&fast_tx->key->conf.tx_pn);
3103 			crypto_hdr[0] = pn;
3104 			crypto_hdr[1] = pn >> 8;
3105 			crypto_hdr[4] = pn >> 16;
3106 			crypto_hdr[5] = pn >> 24;
3107 			crypto_hdr[6] = pn >> 32;
3108 			crypto_hdr[7] = pn >> 40;
3109 			break;
3110 		}
3111 	}
3112 
3113 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3114 		sdata = container_of(sdata->bss,
3115 				     struct ieee80211_sub_if_data, u.ap);
3116 
3117 	__skb_queue_tail(&tx.skbs, skb);
3118 	ieee80211_tx_frags(local, &sdata->vif, &sta->sta, &tx.skbs, false);
3119 	return true;
3120 }
3121 
3122 void __ieee80211_subif_start_xmit(struct sk_buff *skb,
3123 				  struct net_device *dev,
3124 				  u32 info_flags)
3125 {
3126 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
3127 	struct sta_info *sta;
3128 	struct sk_buff *next;
3129 
3130 	if (unlikely(skb->len < ETH_HLEN)) {
3131 		kfree_skb(skb);
3132 		return;
3133 	}
3134 
3135 	rcu_read_lock();
3136 
3137 	if (ieee80211_lookup_ra_sta(sdata, skb, &sta))
3138 		goto out_free;
3139 
3140 	if (!IS_ERR_OR_NULL(sta)) {
3141 		struct ieee80211_fast_tx *fast_tx;
3142 
3143 		fast_tx = rcu_dereference(sta->fast_tx);
3144 
3145 		if (fast_tx &&
3146 		    ieee80211_xmit_fast(sdata, dev, sta, fast_tx, skb))
3147 			goto out;
3148 	}
3149 
3150 	if (skb_is_gso(skb)) {
3151 		struct sk_buff *segs;
3152 
3153 		segs = skb_gso_segment(skb, 0);
3154 		if (IS_ERR(segs)) {
3155 			goto out_free;
3156 		} else if (segs) {
3157 			consume_skb(skb);
3158 			skb = segs;
3159 		}
3160 	} else {
3161 		/* we cannot process non-linear frames on this path */
3162 		if (skb_linearize(skb)) {
3163 			kfree_skb(skb);
3164 			goto out;
3165 		}
3166 
3167 		/* the frame could be fragmented, software-encrypted, and other
3168 		 * things so we cannot really handle checksum offload with it -
3169 		 * fix it up in software before we handle anything else.
3170 		 */
3171 		if (skb->ip_summed == CHECKSUM_PARTIAL) {
3172 			skb_set_transport_header(skb,
3173 						 skb_checksum_start_offset(skb));
3174 			if (skb_checksum_help(skb))
3175 				goto out_free;
3176 		}
3177 	}
3178 
3179 	next = skb;
3180 	while (next) {
3181 		skb = next;
3182 		next = skb->next;
3183 
3184 		skb->prev = NULL;
3185 		skb->next = NULL;
3186 
3187 		skb = ieee80211_build_hdr(sdata, skb, info_flags, sta);
3188 		if (IS_ERR(skb))
3189 			goto out;
3190 
3191 		ieee80211_tx_stats(dev, skb->len);
3192 
3193 		ieee80211_xmit(sdata, sta, skb);
3194 	}
3195 	goto out;
3196  out_free:
3197 	kfree_skb(skb);
3198  out:
3199 	rcu_read_unlock();
3200 }
3201 
3202 /**
3203  * ieee80211_subif_start_xmit - netif start_xmit function for 802.3 vifs
3204  * @skb: packet to be sent
3205  * @dev: incoming interface
3206  *
3207  * On failure skb will be freed.
3208  */
3209 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
3210 				       struct net_device *dev)
3211 {
3212 	__ieee80211_subif_start_xmit(skb, dev, 0);
3213 	return NETDEV_TX_OK;
3214 }
3215 
3216 struct sk_buff *
3217 ieee80211_build_data_template(struct ieee80211_sub_if_data *sdata,
3218 			      struct sk_buff *skb, u32 info_flags)
3219 {
3220 	struct ieee80211_hdr *hdr;
3221 	struct ieee80211_tx_data tx = {
3222 		.local = sdata->local,
3223 		.sdata = sdata,
3224 	};
3225 	struct sta_info *sta;
3226 
3227 	rcu_read_lock();
3228 
3229 	if (ieee80211_lookup_ra_sta(sdata, skb, &sta)) {
3230 		kfree_skb(skb);
3231 		skb = ERR_PTR(-EINVAL);
3232 		goto out;
3233 	}
3234 
3235 	skb = ieee80211_build_hdr(sdata, skb, info_flags, sta);
3236 	if (IS_ERR(skb))
3237 		goto out;
3238 
3239 	hdr = (void *)skb->data;
3240 	tx.sta = sta_info_get(sdata, hdr->addr1);
3241 	tx.skb = skb;
3242 
3243 	if (ieee80211_tx_h_select_key(&tx) != TX_CONTINUE) {
3244 		rcu_read_unlock();
3245 		kfree_skb(skb);
3246 		return ERR_PTR(-EINVAL);
3247 	}
3248 
3249 out:
3250 	rcu_read_unlock();
3251 	return skb;
3252 }
3253 
3254 /*
3255  * ieee80211_clear_tx_pending may not be called in a context where
3256  * it is possible that it packets could come in again.
3257  */
3258 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
3259 {
3260 	struct sk_buff *skb;
3261 	int i;
3262 
3263 	for (i = 0; i < local->hw.queues; i++) {
3264 		while ((skb = skb_dequeue(&local->pending[i])) != NULL)
3265 			ieee80211_free_txskb(&local->hw, skb);
3266 	}
3267 }
3268 
3269 /*
3270  * Returns false if the frame couldn't be transmitted but was queued instead,
3271  * which in this case means re-queued -- take as an indication to stop sending
3272  * more pending frames.
3273  */
3274 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
3275 				     struct sk_buff *skb)
3276 {
3277 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3278 	struct ieee80211_sub_if_data *sdata;
3279 	struct sta_info *sta;
3280 	struct ieee80211_hdr *hdr;
3281 	bool result;
3282 	struct ieee80211_chanctx_conf *chanctx_conf;
3283 
3284 	sdata = vif_to_sdata(info->control.vif);
3285 
3286 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
3287 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
3288 		if (unlikely(!chanctx_conf)) {
3289 			dev_kfree_skb(skb);
3290 			return true;
3291 		}
3292 		info->band = chanctx_conf->def.chan->band;
3293 		result = ieee80211_tx(sdata, NULL, skb, true);
3294 	} else {
3295 		struct sk_buff_head skbs;
3296 
3297 		__skb_queue_head_init(&skbs);
3298 		__skb_queue_tail(&skbs, skb);
3299 
3300 		hdr = (struct ieee80211_hdr *)skb->data;
3301 		sta = sta_info_get(sdata, hdr->addr1);
3302 
3303 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
3304 	}
3305 
3306 	return result;
3307 }
3308 
3309 /*
3310  * Transmit all pending packets. Called from tasklet.
3311  */
3312 void ieee80211_tx_pending(unsigned long data)
3313 {
3314 	struct ieee80211_local *local = (struct ieee80211_local *)data;
3315 	unsigned long flags;
3316 	int i;
3317 	bool txok;
3318 
3319 	rcu_read_lock();
3320 
3321 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
3322 	for (i = 0; i < local->hw.queues; i++) {
3323 		/*
3324 		 * If queue is stopped by something other than due to pending
3325 		 * frames, or we have no pending frames, proceed to next queue.
3326 		 */
3327 		if (local->queue_stop_reasons[i] ||
3328 		    skb_queue_empty(&local->pending[i]))
3329 			continue;
3330 
3331 		while (!skb_queue_empty(&local->pending[i])) {
3332 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
3333 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3334 
3335 			if (WARN_ON(!info->control.vif)) {
3336 				ieee80211_free_txskb(&local->hw, skb);
3337 				continue;
3338 			}
3339 
3340 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
3341 						flags);
3342 
3343 			txok = ieee80211_tx_pending_skb(local, skb);
3344 			spin_lock_irqsave(&local->queue_stop_reason_lock,
3345 					  flags);
3346 			if (!txok)
3347 				break;
3348 		}
3349 
3350 		if (skb_queue_empty(&local->pending[i]))
3351 			ieee80211_propagate_queue_wake(local, i);
3352 	}
3353 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
3354 
3355 	rcu_read_unlock();
3356 }
3357 
3358 /* functions for drivers to get certain frames */
3359 
3360 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
3361 				       struct ps_data *ps, struct sk_buff *skb,
3362 				       bool is_template)
3363 {
3364 	u8 *pos, *tim;
3365 	int aid0 = 0;
3366 	int i, have_bits = 0, n1, n2;
3367 
3368 	/* Generate bitmap for TIM only if there are any STAs in power save
3369 	 * mode. */
3370 	if (atomic_read(&ps->num_sta_ps) > 0)
3371 		/* in the hope that this is faster than
3372 		 * checking byte-for-byte */
3373 		have_bits = !bitmap_empty((unsigned long *)ps->tim,
3374 					  IEEE80211_MAX_AID+1);
3375 	if (!is_template) {
3376 		if (ps->dtim_count == 0)
3377 			ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
3378 		else
3379 			ps->dtim_count--;
3380 	}
3381 
3382 	tim = pos = (u8 *) skb_put(skb, 6);
3383 	*pos++ = WLAN_EID_TIM;
3384 	*pos++ = 4;
3385 	*pos++ = ps->dtim_count;
3386 	*pos++ = sdata->vif.bss_conf.dtim_period;
3387 
3388 	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
3389 		aid0 = 1;
3390 
3391 	ps->dtim_bc_mc = aid0 == 1;
3392 
3393 	if (have_bits) {
3394 		/* Find largest even number N1 so that bits numbered 1 through
3395 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
3396 		 * (N2 + 1) x 8 through 2007 are 0. */
3397 		n1 = 0;
3398 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
3399 			if (ps->tim[i]) {
3400 				n1 = i & 0xfe;
3401 				break;
3402 			}
3403 		}
3404 		n2 = n1;
3405 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
3406 			if (ps->tim[i]) {
3407 				n2 = i;
3408 				break;
3409 			}
3410 		}
3411 
3412 		/* Bitmap control */
3413 		*pos++ = n1 | aid0;
3414 		/* Part Virt Bitmap */
3415 		skb_put(skb, n2 - n1);
3416 		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
3417 
3418 		tim[1] = n2 - n1 + 4;
3419 	} else {
3420 		*pos++ = aid0; /* Bitmap control */
3421 		*pos++ = 0; /* Part Virt Bitmap */
3422 	}
3423 }
3424 
3425 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
3426 				    struct ps_data *ps, struct sk_buff *skb,
3427 				    bool is_template)
3428 {
3429 	struct ieee80211_local *local = sdata->local;
3430 
3431 	/*
3432 	 * Not very nice, but we want to allow the driver to call
3433 	 * ieee80211_beacon_get() as a response to the set_tim()
3434 	 * callback. That, however, is already invoked under the
3435 	 * sta_lock to guarantee consistent and race-free update
3436 	 * of the tim bitmap in mac80211 and the driver.
3437 	 */
3438 	if (local->tim_in_locked_section) {
3439 		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
3440 	} else {
3441 		spin_lock_bh(&local->tim_lock);
3442 		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
3443 		spin_unlock_bh(&local->tim_lock);
3444 	}
3445 
3446 	return 0;
3447 }
3448 
3449 static void ieee80211_set_csa(struct ieee80211_sub_if_data *sdata,
3450 			      struct beacon_data *beacon)
3451 {
3452 	struct probe_resp *resp;
3453 	u8 *beacon_data;
3454 	size_t beacon_data_len;
3455 	int i;
3456 	u8 count = beacon->csa_current_counter;
3457 
3458 	switch (sdata->vif.type) {
3459 	case NL80211_IFTYPE_AP:
3460 		beacon_data = beacon->tail;
3461 		beacon_data_len = beacon->tail_len;
3462 		break;
3463 	case NL80211_IFTYPE_ADHOC:
3464 		beacon_data = beacon->head;
3465 		beacon_data_len = beacon->head_len;
3466 		break;
3467 	case NL80211_IFTYPE_MESH_POINT:
3468 		beacon_data = beacon->head;
3469 		beacon_data_len = beacon->head_len;
3470 		break;
3471 	default:
3472 		return;
3473 	}
3474 
3475 	rcu_read_lock();
3476 	for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; ++i) {
3477 		resp = rcu_dereference(sdata->u.ap.probe_resp);
3478 
3479 		if (beacon->csa_counter_offsets[i]) {
3480 			if (WARN_ON_ONCE(beacon->csa_counter_offsets[i] >=
3481 					 beacon_data_len)) {
3482 				rcu_read_unlock();
3483 				return;
3484 			}
3485 
3486 			beacon_data[beacon->csa_counter_offsets[i]] = count;
3487 		}
3488 
3489 		if (sdata->vif.type == NL80211_IFTYPE_AP && resp)
3490 			resp->data[resp->csa_counter_offsets[i]] = count;
3491 	}
3492 	rcu_read_unlock();
3493 }
3494 
3495 static u8 __ieee80211_csa_update_counter(struct beacon_data *beacon)
3496 {
3497 	beacon->csa_current_counter--;
3498 
3499 	/* the counter should never reach 0 */
3500 	WARN_ON_ONCE(!beacon->csa_current_counter);
3501 
3502 	return beacon->csa_current_counter;
3503 }
3504 
3505 u8 ieee80211_csa_update_counter(struct ieee80211_vif *vif)
3506 {
3507 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3508 	struct beacon_data *beacon = NULL;
3509 	u8 count = 0;
3510 
3511 	rcu_read_lock();
3512 
3513 	if (sdata->vif.type == NL80211_IFTYPE_AP)
3514 		beacon = rcu_dereference(sdata->u.ap.beacon);
3515 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
3516 		beacon = rcu_dereference(sdata->u.ibss.presp);
3517 	else if (ieee80211_vif_is_mesh(&sdata->vif))
3518 		beacon = rcu_dereference(sdata->u.mesh.beacon);
3519 
3520 	if (!beacon)
3521 		goto unlock;
3522 
3523 	count = __ieee80211_csa_update_counter(beacon);
3524 
3525 unlock:
3526 	rcu_read_unlock();
3527 	return count;
3528 }
3529 EXPORT_SYMBOL(ieee80211_csa_update_counter);
3530 
3531 bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
3532 {
3533 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3534 	struct beacon_data *beacon = NULL;
3535 	u8 *beacon_data;
3536 	size_t beacon_data_len;
3537 	int ret = false;
3538 
3539 	if (!ieee80211_sdata_running(sdata))
3540 		return false;
3541 
3542 	rcu_read_lock();
3543 	if (vif->type == NL80211_IFTYPE_AP) {
3544 		struct ieee80211_if_ap *ap = &sdata->u.ap;
3545 
3546 		beacon = rcu_dereference(ap->beacon);
3547 		if (WARN_ON(!beacon || !beacon->tail))
3548 			goto out;
3549 		beacon_data = beacon->tail;
3550 		beacon_data_len = beacon->tail_len;
3551 	} else if (vif->type == NL80211_IFTYPE_ADHOC) {
3552 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
3553 
3554 		beacon = rcu_dereference(ifibss->presp);
3555 		if (!beacon)
3556 			goto out;
3557 
3558 		beacon_data = beacon->head;
3559 		beacon_data_len = beacon->head_len;
3560 	} else if (vif->type == NL80211_IFTYPE_MESH_POINT) {
3561 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
3562 
3563 		beacon = rcu_dereference(ifmsh->beacon);
3564 		if (!beacon)
3565 			goto out;
3566 
3567 		beacon_data = beacon->head;
3568 		beacon_data_len = beacon->head_len;
3569 	} else {
3570 		WARN_ON(1);
3571 		goto out;
3572 	}
3573 
3574 	if (!beacon->csa_counter_offsets[0])
3575 		goto out;
3576 
3577 	if (WARN_ON_ONCE(beacon->csa_counter_offsets[0] > beacon_data_len))
3578 		goto out;
3579 
3580 	if (beacon_data[beacon->csa_counter_offsets[0]] == 1)
3581 		ret = true;
3582  out:
3583 	rcu_read_unlock();
3584 
3585 	return ret;
3586 }
3587 EXPORT_SYMBOL(ieee80211_csa_is_complete);
3588 
3589 static struct sk_buff *
3590 __ieee80211_beacon_get(struct ieee80211_hw *hw,
3591 		       struct ieee80211_vif *vif,
3592 		       struct ieee80211_mutable_offsets *offs,
3593 		       bool is_template)
3594 {
3595 	struct ieee80211_local *local = hw_to_local(hw);
3596 	struct beacon_data *beacon = NULL;
3597 	struct sk_buff *skb = NULL;
3598 	struct ieee80211_tx_info *info;
3599 	struct ieee80211_sub_if_data *sdata = NULL;
3600 	enum nl80211_band band;
3601 	struct ieee80211_tx_rate_control txrc;
3602 	struct ieee80211_chanctx_conf *chanctx_conf;
3603 	int csa_off_base = 0;
3604 
3605 	rcu_read_lock();
3606 
3607 	sdata = vif_to_sdata(vif);
3608 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
3609 
3610 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
3611 		goto out;
3612 
3613 	if (offs)
3614 		memset(offs, 0, sizeof(*offs));
3615 
3616 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
3617 		struct ieee80211_if_ap *ap = &sdata->u.ap;
3618 
3619 		beacon = rcu_dereference(ap->beacon);
3620 		if (beacon) {
3621 			if (beacon->csa_counter_offsets[0]) {
3622 				if (!is_template)
3623 					__ieee80211_csa_update_counter(beacon);
3624 
3625 				ieee80211_set_csa(sdata, beacon);
3626 			}
3627 
3628 			/*
3629 			 * headroom, head length,
3630 			 * tail length and maximum TIM length
3631 			 */
3632 			skb = dev_alloc_skb(local->tx_headroom +
3633 					    beacon->head_len +
3634 					    beacon->tail_len + 256 +
3635 					    local->hw.extra_beacon_tailroom);
3636 			if (!skb)
3637 				goto out;
3638 
3639 			skb_reserve(skb, local->tx_headroom);
3640 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
3641 			       beacon->head_len);
3642 
3643 			ieee80211_beacon_add_tim(sdata, &ap->ps, skb,
3644 						 is_template);
3645 
3646 			if (offs) {
3647 				offs->tim_offset = beacon->head_len;
3648 				offs->tim_length = skb->len - beacon->head_len;
3649 
3650 				/* for AP the csa offsets are from tail */
3651 				csa_off_base = skb->len;
3652 			}
3653 
3654 			if (beacon->tail)
3655 				memcpy(skb_put(skb, beacon->tail_len),
3656 				       beacon->tail, beacon->tail_len);
3657 		} else
3658 			goto out;
3659 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
3660 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
3661 		struct ieee80211_hdr *hdr;
3662 
3663 		beacon = rcu_dereference(ifibss->presp);
3664 		if (!beacon)
3665 			goto out;
3666 
3667 		if (beacon->csa_counter_offsets[0]) {
3668 			if (!is_template)
3669 				__ieee80211_csa_update_counter(beacon);
3670 
3671 			ieee80211_set_csa(sdata, beacon);
3672 		}
3673 
3674 		skb = dev_alloc_skb(local->tx_headroom + beacon->head_len +
3675 				    local->hw.extra_beacon_tailroom);
3676 		if (!skb)
3677 			goto out;
3678 		skb_reserve(skb, local->tx_headroom);
3679 		memcpy(skb_put(skb, beacon->head_len), beacon->head,
3680 		       beacon->head_len);
3681 
3682 		hdr = (struct ieee80211_hdr *) skb->data;
3683 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
3684 						 IEEE80211_STYPE_BEACON);
3685 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
3686 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
3687 
3688 		beacon = rcu_dereference(ifmsh->beacon);
3689 		if (!beacon)
3690 			goto out;
3691 
3692 		if (beacon->csa_counter_offsets[0]) {
3693 			if (!is_template)
3694 				/* TODO: For mesh csa_counter is in TU, so
3695 				 * decrementing it by one isn't correct, but
3696 				 * for now we leave it consistent with overall
3697 				 * mac80211's behavior.
3698 				 */
3699 				__ieee80211_csa_update_counter(beacon);
3700 
3701 			ieee80211_set_csa(sdata, beacon);
3702 		}
3703 
3704 		if (ifmsh->sync_ops)
3705 			ifmsh->sync_ops->adjust_tbtt(sdata, beacon);
3706 
3707 		skb = dev_alloc_skb(local->tx_headroom +
3708 				    beacon->head_len +
3709 				    256 + /* TIM IE */
3710 				    beacon->tail_len +
3711 				    local->hw.extra_beacon_tailroom);
3712 		if (!skb)
3713 			goto out;
3714 		skb_reserve(skb, local->tx_headroom);
3715 		memcpy(skb_put(skb, beacon->head_len), beacon->head,
3716 		       beacon->head_len);
3717 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb, is_template);
3718 
3719 		if (offs) {
3720 			offs->tim_offset = beacon->head_len;
3721 			offs->tim_length = skb->len - beacon->head_len;
3722 		}
3723 
3724 		memcpy(skb_put(skb, beacon->tail_len), beacon->tail,
3725 		       beacon->tail_len);
3726 	} else {
3727 		WARN_ON(1);
3728 		goto out;
3729 	}
3730 
3731 	/* CSA offsets */
3732 	if (offs && beacon) {
3733 		int i;
3734 
3735 		for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; i++) {
3736 			u16 csa_off = beacon->csa_counter_offsets[i];
3737 
3738 			if (!csa_off)
3739 				continue;
3740 
3741 			offs->csa_counter_offs[i] = csa_off_base + csa_off;
3742 		}
3743 	}
3744 
3745 	band = chanctx_conf->def.chan->band;
3746 
3747 	info = IEEE80211_SKB_CB(skb);
3748 
3749 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
3750 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
3751 	info->band = band;
3752 
3753 	memset(&txrc, 0, sizeof(txrc));
3754 	txrc.hw = hw;
3755 	txrc.sband = local->hw.wiphy->bands[band];
3756 	txrc.bss_conf = &sdata->vif.bss_conf;
3757 	txrc.skb = skb;
3758 	txrc.reported_rate.idx = -1;
3759 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
3760 	if (txrc.rate_idx_mask == (1 << txrc.sband->n_bitrates) - 1)
3761 		txrc.max_rate_idx = -1;
3762 	else
3763 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
3764 	txrc.bss = true;
3765 	rate_control_get_rate(sdata, NULL, &txrc);
3766 
3767 	info->control.vif = vif;
3768 
3769 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
3770 			IEEE80211_TX_CTL_ASSIGN_SEQ |
3771 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
3772  out:
3773 	rcu_read_unlock();
3774 	return skb;
3775 
3776 }
3777 
3778 struct sk_buff *
3779 ieee80211_beacon_get_template(struct ieee80211_hw *hw,
3780 			      struct ieee80211_vif *vif,
3781 			      struct ieee80211_mutable_offsets *offs)
3782 {
3783 	return __ieee80211_beacon_get(hw, vif, offs, true);
3784 }
3785 EXPORT_SYMBOL(ieee80211_beacon_get_template);
3786 
3787 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
3788 					 struct ieee80211_vif *vif,
3789 					 u16 *tim_offset, u16 *tim_length)
3790 {
3791 	struct ieee80211_mutable_offsets offs = {};
3792 	struct sk_buff *bcn = __ieee80211_beacon_get(hw, vif, &offs, false);
3793 	struct sk_buff *copy;
3794 	struct ieee80211_supported_band *sband;
3795 	int shift;
3796 
3797 	if (!bcn)
3798 		return bcn;
3799 
3800 	if (tim_offset)
3801 		*tim_offset = offs.tim_offset;
3802 
3803 	if (tim_length)
3804 		*tim_length = offs.tim_length;
3805 
3806 	if (ieee80211_hw_check(hw, BEACON_TX_STATUS) ||
3807 	    !hw_to_local(hw)->monitors)
3808 		return bcn;
3809 
3810 	/* send a copy to monitor interfaces */
3811 	copy = skb_copy(bcn, GFP_ATOMIC);
3812 	if (!copy)
3813 		return bcn;
3814 
3815 	shift = ieee80211_vif_get_shift(vif);
3816 	sband = hw->wiphy->bands[ieee80211_get_sdata_band(vif_to_sdata(vif))];
3817 	ieee80211_tx_monitor(hw_to_local(hw), copy, sband, 1, shift, false);
3818 
3819 	return bcn;
3820 }
3821 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
3822 
3823 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
3824 					struct ieee80211_vif *vif)
3825 {
3826 	struct ieee80211_if_ap *ap = NULL;
3827 	struct sk_buff *skb = NULL;
3828 	struct probe_resp *presp = NULL;
3829 	struct ieee80211_hdr *hdr;
3830 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3831 
3832 	if (sdata->vif.type != NL80211_IFTYPE_AP)
3833 		return NULL;
3834 
3835 	rcu_read_lock();
3836 
3837 	ap = &sdata->u.ap;
3838 	presp = rcu_dereference(ap->probe_resp);
3839 	if (!presp)
3840 		goto out;
3841 
3842 	skb = dev_alloc_skb(presp->len);
3843 	if (!skb)
3844 		goto out;
3845 
3846 	memcpy(skb_put(skb, presp->len), presp->data, presp->len);
3847 
3848 	hdr = (struct ieee80211_hdr *) skb->data;
3849 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
3850 
3851 out:
3852 	rcu_read_unlock();
3853 	return skb;
3854 }
3855 EXPORT_SYMBOL(ieee80211_proberesp_get);
3856 
3857 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
3858 				     struct ieee80211_vif *vif)
3859 {
3860 	struct ieee80211_sub_if_data *sdata;
3861 	struct ieee80211_if_managed *ifmgd;
3862 	struct ieee80211_pspoll *pspoll;
3863 	struct ieee80211_local *local;
3864 	struct sk_buff *skb;
3865 
3866 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
3867 		return NULL;
3868 
3869 	sdata = vif_to_sdata(vif);
3870 	ifmgd = &sdata->u.mgd;
3871 	local = sdata->local;
3872 
3873 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
3874 	if (!skb)
3875 		return NULL;
3876 
3877 	skb_reserve(skb, local->hw.extra_tx_headroom);
3878 
3879 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
3880 	memset(pspoll, 0, sizeof(*pspoll));
3881 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
3882 					    IEEE80211_STYPE_PSPOLL);
3883 	pspoll->aid = cpu_to_le16(ifmgd->aid);
3884 
3885 	/* aid in PS-Poll has its two MSBs each set to 1 */
3886 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
3887 
3888 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
3889 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
3890 
3891 	return skb;
3892 }
3893 EXPORT_SYMBOL(ieee80211_pspoll_get);
3894 
3895 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
3896 				       struct ieee80211_vif *vif)
3897 {
3898 	struct ieee80211_hdr_3addr *nullfunc;
3899 	struct ieee80211_sub_if_data *sdata;
3900 	struct ieee80211_if_managed *ifmgd;
3901 	struct ieee80211_local *local;
3902 	struct sk_buff *skb;
3903 
3904 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
3905 		return NULL;
3906 
3907 	sdata = vif_to_sdata(vif);
3908 	ifmgd = &sdata->u.mgd;
3909 	local = sdata->local;
3910 
3911 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
3912 	if (!skb)
3913 		return NULL;
3914 
3915 	skb_reserve(skb, local->hw.extra_tx_headroom);
3916 
3917 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
3918 							  sizeof(*nullfunc));
3919 	memset(nullfunc, 0, sizeof(*nullfunc));
3920 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
3921 					      IEEE80211_STYPE_NULLFUNC |
3922 					      IEEE80211_FCTL_TODS);
3923 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
3924 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
3925 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
3926 
3927 	return skb;
3928 }
3929 EXPORT_SYMBOL(ieee80211_nullfunc_get);
3930 
3931 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
3932 				       const u8 *src_addr,
3933 				       const u8 *ssid, size_t ssid_len,
3934 				       size_t tailroom)
3935 {
3936 	struct ieee80211_local *local = hw_to_local(hw);
3937 	struct ieee80211_hdr_3addr *hdr;
3938 	struct sk_buff *skb;
3939 	size_t ie_ssid_len;
3940 	u8 *pos;
3941 
3942 	ie_ssid_len = 2 + ssid_len;
3943 
3944 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
3945 			    ie_ssid_len + tailroom);
3946 	if (!skb)
3947 		return NULL;
3948 
3949 	skb_reserve(skb, local->hw.extra_tx_headroom);
3950 
3951 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
3952 	memset(hdr, 0, sizeof(*hdr));
3953 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
3954 					 IEEE80211_STYPE_PROBE_REQ);
3955 	eth_broadcast_addr(hdr->addr1);
3956 	memcpy(hdr->addr2, src_addr, ETH_ALEN);
3957 	eth_broadcast_addr(hdr->addr3);
3958 
3959 	pos = skb_put(skb, ie_ssid_len);
3960 	*pos++ = WLAN_EID_SSID;
3961 	*pos++ = ssid_len;
3962 	if (ssid_len)
3963 		memcpy(pos, ssid, ssid_len);
3964 	pos += ssid_len;
3965 
3966 	return skb;
3967 }
3968 EXPORT_SYMBOL(ieee80211_probereq_get);
3969 
3970 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
3971 		       const void *frame, size_t frame_len,
3972 		       const struct ieee80211_tx_info *frame_txctl,
3973 		       struct ieee80211_rts *rts)
3974 {
3975 	const struct ieee80211_hdr *hdr = frame;
3976 
3977 	rts->frame_control =
3978 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
3979 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
3980 					       frame_txctl);
3981 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
3982 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
3983 }
3984 EXPORT_SYMBOL(ieee80211_rts_get);
3985 
3986 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
3987 			     const void *frame, size_t frame_len,
3988 			     const struct ieee80211_tx_info *frame_txctl,
3989 			     struct ieee80211_cts *cts)
3990 {
3991 	const struct ieee80211_hdr *hdr = frame;
3992 
3993 	cts->frame_control =
3994 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
3995 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
3996 						     frame_len, frame_txctl);
3997 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
3998 }
3999 EXPORT_SYMBOL(ieee80211_ctstoself_get);
4000 
4001 struct sk_buff *
4002 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
4003 			  struct ieee80211_vif *vif)
4004 {
4005 	struct ieee80211_local *local = hw_to_local(hw);
4006 	struct sk_buff *skb = NULL;
4007 	struct ieee80211_tx_data tx;
4008 	struct ieee80211_sub_if_data *sdata;
4009 	struct ps_data *ps;
4010 	struct ieee80211_tx_info *info;
4011 	struct ieee80211_chanctx_conf *chanctx_conf;
4012 
4013 	sdata = vif_to_sdata(vif);
4014 
4015 	rcu_read_lock();
4016 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
4017 
4018 	if (!chanctx_conf)
4019 		goto out;
4020 
4021 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
4022 		struct beacon_data *beacon =
4023 				rcu_dereference(sdata->u.ap.beacon);
4024 
4025 		if (!beacon || !beacon->head)
4026 			goto out;
4027 
4028 		ps = &sdata->u.ap.ps;
4029 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
4030 		ps = &sdata->u.mesh.ps;
4031 	} else {
4032 		goto out;
4033 	}
4034 
4035 	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
4036 		goto out; /* send buffered bc/mc only after DTIM beacon */
4037 
4038 	while (1) {
4039 		skb = skb_dequeue(&ps->bc_buf);
4040 		if (!skb)
4041 			goto out;
4042 		local->total_ps_buffered--;
4043 
4044 		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
4045 			struct ieee80211_hdr *hdr =
4046 				(struct ieee80211_hdr *) skb->data;
4047 			/* more buffered multicast/broadcast frames ==> set
4048 			 * MoreData flag in IEEE 802.11 header to inform PS
4049 			 * STAs */
4050 			hdr->frame_control |=
4051 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
4052 		}
4053 
4054 		if (sdata->vif.type == NL80211_IFTYPE_AP)
4055 			sdata = IEEE80211_DEV_TO_SUB_IF(skb->dev);
4056 		if (!ieee80211_tx_prepare(sdata, &tx, NULL, skb))
4057 			break;
4058 		dev_kfree_skb_any(skb);
4059 	}
4060 
4061 	info = IEEE80211_SKB_CB(skb);
4062 
4063 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
4064 	info->band = chanctx_conf->def.chan->band;
4065 
4066 	if (invoke_tx_handlers(&tx))
4067 		skb = NULL;
4068  out:
4069 	rcu_read_unlock();
4070 
4071 	return skb;
4072 }
4073 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
4074 
4075 int ieee80211_reserve_tid(struct ieee80211_sta *pubsta, u8 tid)
4076 {
4077 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
4078 	struct ieee80211_sub_if_data *sdata = sta->sdata;
4079 	struct ieee80211_local *local = sdata->local;
4080 	int ret;
4081 	u32 queues;
4082 
4083 	lockdep_assert_held(&local->sta_mtx);
4084 
4085 	/* only some cases are supported right now */
4086 	switch (sdata->vif.type) {
4087 	case NL80211_IFTYPE_STATION:
4088 	case NL80211_IFTYPE_AP:
4089 	case NL80211_IFTYPE_AP_VLAN:
4090 		break;
4091 	default:
4092 		WARN_ON(1);
4093 		return -EINVAL;
4094 	}
4095 
4096 	if (WARN_ON(tid >= IEEE80211_NUM_UPS))
4097 		return -EINVAL;
4098 
4099 	if (sta->reserved_tid == tid) {
4100 		ret = 0;
4101 		goto out;
4102 	}
4103 
4104 	if (sta->reserved_tid != IEEE80211_TID_UNRESERVED) {
4105 		sdata_err(sdata, "TID reservation already active\n");
4106 		ret = -EALREADY;
4107 		goto out;
4108 	}
4109 
4110 	ieee80211_stop_vif_queues(sdata->local, sdata,
4111 				  IEEE80211_QUEUE_STOP_REASON_RESERVE_TID);
4112 
4113 	synchronize_net();
4114 
4115 	/* Tear down BA sessions so we stop aggregating on this TID */
4116 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
4117 		set_sta_flag(sta, WLAN_STA_BLOCK_BA);
4118 		__ieee80211_stop_tx_ba_session(sta, tid,
4119 					       AGG_STOP_LOCAL_REQUEST);
4120 	}
4121 
4122 	queues = BIT(sdata->vif.hw_queue[ieee802_1d_to_ac[tid]]);
4123 	__ieee80211_flush_queues(local, sdata, queues, false);
4124 
4125 	sta->reserved_tid = tid;
4126 
4127 	ieee80211_wake_vif_queues(local, sdata,
4128 				  IEEE80211_QUEUE_STOP_REASON_RESERVE_TID);
4129 
4130 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION))
4131 		clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
4132 
4133 	ret = 0;
4134  out:
4135 	return ret;
4136 }
4137 EXPORT_SYMBOL(ieee80211_reserve_tid);
4138 
4139 void ieee80211_unreserve_tid(struct ieee80211_sta *pubsta, u8 tid)
4140 {
4141 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
4142 	struct ieee80211_sub_if_data *sdata = sta->sdata;
4143 
4144 	lockdep_assert_held(&sdata->local->sta_mtx);
4145 
4146 	/* only some cases are supported right now */
4147 	switch (sdata->vif.type) {
4148 	case NL80211_IFTYPE_STATION:
4149 	case NL80211_IFTYPE_AP:
4150 	case NL80211_IFTYPE_AP_VLAN:
4151 		break;
4152 	default:
4153 		WARN_ON(1);
4154 		return;
4155 	}
4156 
4157 	if (tid != sta->reserved_tid) {
4158 		sdata_err(sdata, "TID to unreserve (%d) isn't reserved\n", tid);
4159 		return;
4160 	}
4161 
4162 	sta->reserved_tid = IEEE80211_TID_UNRESERVED;
4163 }
4164 EXPORT_SYMBOL(ieee80211_unreserve_tid);
4165 
4166 void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
4167 				 struct sk_buff *skb, int tid,
4168 				 enum nl80211_band band)
4169 {
4170 	int ac = ieee802_1d_to_ac[tid & 7];
4171 
4172 	skb_reset_mac_header(skb);
4173 	skb_reset_network_header(skb);
4174 	skb_reset_transport_header(skb);
4175 
4176 	skb_set_queue_mapping(skb, ac);
4177 	skb->priority = tid;
4178 
4179 	skb->dev = sdata->dev;
4180 
4181 	/*
4182 	 * The other path calling ieee80211_xmit is from the tasklet,
4183 	 * and while we can handle concurrent transmissions locking
4184 	 * requirements are that we do not come into tx with bhs on.
4185 	 */
4186 	local_bh_disable();
4187 	IEEE80211_SKB_CB(skb)->band = band;
4188 	ieee80211_xmit(sdata, NULL, skb);
4189 	local_bh_enable();
4190 }
4191