xref: /openbmc/linux/net/mac80211/tx.c (revision 930beb5a)
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  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  *
12  * Transmit and frame generation functions.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/skbuff.h>
18 #include <linux/etherdevice.h>
19 #include <linux/bitmap.h>
20 #include <linux/rcupdate.h>
21 #include <linux/export.h>
22 #include <net/net_namespace.h>
23 #include <net/ieee80211_radiotap.h>
24 #include <net/cfg80211.h>
25 #include <net/mac80211.h>
26 #include <asm/unaligned.h>
27 
28 #include "ieee80211_i.h"
29 #include "driver-ops.h"
30 #include "led.h"
31 #include "mesh.h"
32 #include "wep.h"
33 #include "wpa.h"
34 #include "wme.h"
35 #include "rate.h"
36 
37 /* misc utils */
38 
39 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx,
40 				 struct sk_buff *skb, int group_addr,
41 				 int next_frag_len)
42 {
43 	int rate, mrate, erp, dur, i, shift = 0;
44 	struct ieee80211_rate *txrate;
45 	struct ieee80211_local *local = tx->local;
46 	struct ieee80211_supported_band *sband;
47 	struct ieee80211_hdr *hdr;
48 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
49 	struct ieee80211_chanctx_conf *chanctx_conf;
50 	u32 rate_flags = 0;
51 
52 	rcu_read_lock();
53 	chanctx_conf = rcu_dereference(tx->sdata->vif.chanctx_conf);
54 	if (chanctx_conf) {
55 		shift = ieee80211_chandef_get_shift(&chanctx_conf->def);
56 		rate_flags = ieee80211_chandef_rate_flags(&chanctx_conf->def);
57 	}
58 	rcu_read_unlock();
59 
60 	/* assume HW handles this */
61 	if (tx->rate.flags & IEEE80211_TX_RC_MCS)
62 		return 0;
63 
64 	/* uh huh? */
65 	if (WARN_ON_ONCE(tx->rate.idx < 0))
66 		return 0;
67 
68 	sband = local->hw.wiphy->bands[info->band];
69 	txrate = &sband->bitrates[tx->rate.idx];
70 
71 	erp = txrate->flags & IEEE80211_RATE_ERP_G;
72 
73 	/*
74 	 * data and mgmt (except PS Poll):
75 	 * - during CFP: 32768
76 	 * - during contention period:
77 	 *   if addr1 is group address: 0
78 	 *   if more fragments = 0 and addr1 is individual address: time to
79 	 *      transmit one ACK plus SIFS
80 	 *   if more fragments = 1 and addr1 is individual address: time to
81 	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
82 	 *
83 	 * IEEE 802.11, 9.6:
84 	 * - control response frame (CTS or ACK) shall be transmitted using the
85 	 *   same rate as the immediately previous frame in the frame exchange
86 	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
87 	 *   at the highest possible rate belonging to the PHY rates in the
88 	 *   BSSBasicRateSet
89 	 */
90 	hdr = (struct ieee80211_hdr *)skb->data;
91 	if (ieee80211_is_ctl(hdr->frame_control)) {
92 		/* TODO: These control frames are not currently sent by
93 		 * mac80211, but should they be implemented, this function
94 		 * needs to be updated to support duration field calculation.
95 		 *
96 		 * RTS: time needed to transmit pending data/mgmt frame plus
97 		 *    one CTS frame plus one ACK frame plus 3 x SIFS
98 		 * CTS: duration of immediately previous RTS minus time
99 		 *    required to transmit CTS and its SIFS
100 		 * ACK: 0 if immediately previous directed data/mgmt had
101 		 *    more=0, with more=1 duration in ACK frame is duration
102 		 *    from previous frame minus time needed to transmit ACK
103 		 *    and its SIFS
104 		 * PS Poll: BIT(15) | BIT(14) | aid
105 		 */
106 		return 0;
107 	}
108 
109 	/* data/mgmt */
110 	if (0 /* FIX: data/mgmt during CFP */)
111 		return cpu_to_le16(32768);
112 
113 	if (group_addr) /* Group address as the destination - no ACK */
114 		return 0;
115 
116 	/* Individual destination address:
117 	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
118 	 * CTS and ACK frames shall be transmitted using the highest rate in
119 	 * basic rate set that is less than or equal to the rate of the
120 	 * immediately previous frame and that is using the same modulation
121 	 * (CCK or OFDM). If no basic rate set matches with these requirements,
122 	 * the highest mandatory rate of the PHY that is less than or equal to
123 	 * the rate of the previous frame is used.
124 	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
125 	 */
126 	rate = -1;
127 	/* use lowest available if everything fails */
128 	mrate = sband->bitrates[0].bitrate;
129 	for (i = 0; i < sband->n_bitrates; i++) {
130 		struct ieee80211_rate *r = &sband->bitrates[i];
131 
132 		if (r->bitrate > txrate->bitrate)
133 			break;
134 
135 		if ((rate_flags & r->flags) != rate_flags)
136 			continue;
137 
138 		if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
139 			rate = DIV_ROUND_UP(r->bitrate, 1 << shift);
140 
141 		switch (sband->band) {
142 		case IEEE80211_BAND_2GHZ: {
143 			u32 flag;
144 			if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
145 				flag = IEEE80211_RATE_MANDATORY_G;
146 			else
147 				flag = IEEE80211_RATE_MANDATORY_B;
148 			if (r->flags & flag)
149 				mrate = r->bitrate;
150 			break;
151 		}
152 		case IEEE80211_BAND_5GHZ:
153 			if (r->flags & IEEE80211_RATE_MANDATORY_A)
154 				mrate = r->bitrate;
155 			break;
156 		case IEEE80211_BAND_60GHZ:
157 			/* TODO, for now fall through */
158 		case IEEE80211_NUM_BANDS:
159 			WARN_ON(1);
160 			break;
161 		}
162 	}
163 	if (rate == -1) {
164 		/* No matching basic rate found; use highest suitable mandatory
165 		 * PHY rate */
166 		rate = DIV_ROUND_UP(mrate, 1 << shift);
167 	}
168 
169 	/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
170 	if (ieee80211_is_data_qos(hdr->frame_control) &&
171 	    *(ieee80211_get_qos_ctl(hdr)) & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
172 		dur = 0;
173 	else
174 		/* Time needed to transmit ACK
175 		 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
176 		 * to closest integer */
177 		dur = ieee80211_frame_duration(sband->band, 10, rate, erp,
178 				tx->sdata->vif.bss_conf.use_short_preamble,
179 				shift);
180 
181 	if (next_frag_len) {
182 		/* Frame is fragmented: duration increases with time needed to
183 		 * transmit next fragment plus ACK and 2 x SIFS. */
184 		dur *= 2; /* ACK + SIFS */
185 		/* next fragment */
186 		dur += ieee80211_frame_duration(sband->band, next_frag_len,
187 				txrate->bitrate, erp,
188 				tx->sdata->vif.bss_conf.use_short_preamble,
189 				shift);
190 	}
191 
192 	return cpu_to_le16(dur);
193 }
194 
195 /* tx handlers */
196 static ieee80211_tx_result debug_noinline
197 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
198 {
199 	struct ieee80211_local *local = tx->local;
200 	struct ieee80211_if_managed *ifmgd;
201 
202 	/* driver doesn't support power save */
203 	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS))
204 		return TX_CONTINUE;
205 
206 	/* hardware does dynamic power save */
207 	if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)
208 		return TX_CONTINUE;
209 
210 	/* dynamic power save disabled */
211 	if (local->hw.conf.dynamic_ps_timeout <= 0)
212 		return TX_CONTINUE;
213 
214 	/* we are scanning, don't enable power save */
215 	if (local->scanning)
216 		return TX_CONTINUE;
217 
218 	if (!local->ps_sdata)
219 		return TX_CONTINUE;
220 
221 	/* No point if we're going to suspend */
222 	if (local->quiescing)
223 		return TX_CONTINUE;
224 
225 	/* dynamic ps is supported only in managed mode */
226 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
227 		return TX_CONTINUE;
228 
229 	ifmgd = &tx->sdata->u.mgd;
230 
231 	/*
232 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
233 	 * u-apsd enabled and the frame is in voip class. This effectively
234 	 * means that even if all access categories have u-apsd enabled, in
235 	 * practise u-apsd is only used with the voip ac. This is a
236 	 * workaround for the case when received voip class packets do not
237 	 * have correct qos tag for some reason, due the network or the
238 	 * peer application.
239 	 *
240 	 * Note: ifmgd->uapsd_queues access is racy here. If the value is
241 	 * changed via debugfs, user needs to reassociate manually to have
242 	 * everything in sync.
243 	 */
244 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
245 	    (ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
246 	    skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
247 		return TX_CONTINUE;
248 
249 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
250 		ieee80211_stop_queues_by_reason(&local->hw,
251 						IEEE80211_MAX_QUEUE_MAP,
252 						IEEE80211_QUEUE_STOP_REASON_PS);
253 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
254 		ieee80211_queue_work(&local->hw,
255 				     &local->dynamic_ps_disable_work);
256 	}
257 
258 	/* Don't restart the timer if we're not disassociated */
259 	if (!ifmgd->associated)
260 		return TX_CONTINUE;
261 
262 	mod_timer(&local->dynamic_ps_timer, jiffies +
263 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
264 
265 	return TX_CONTINUE;
266 }
267 
268 static ieee80211_tx_result debug_noinline
269 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
270 {
271 
272 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
273 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
274 	bool assoc = false;
275 
276 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
277 		return TX_CONTINUE;
278 
279 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
280 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
281 	    !ieee80211_is_probe_req(hdr->frame_control) &&
282 	    !ieee80211_is_nullfunc(hdr->frame_control))
283 		/*
284 		 * When software scanning only nullfunc frames (to notify
285 		 * the sleep state to the AP) and probe requests (for the
286 		 * active scan) are allowed, all other frames should not be
287 		 * sent and we should not get here, but if we do
288 		 * nonetheless, drop them to avoid sending them
289 		 * off-channel. See the link below and
290 		 * ieee80211_start_scan() for more.
291 		 *
292 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
293 		 */
294 		return TX_DROP;
295 
296 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
297 		return TX_CONTINUE;
298 
299 	if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
300 		return TX_CONTINUE;
301 
302 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
303 		return TX_CONTINUE;
304 
305 	if (tx->sta)
306 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
307 
308 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
309 		if (unlikely(!assoc &&
310 			     ieee80211_is_data(hdr->frame_control))) {
311 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
312 			sdata_info(tx->sdata,
313 				   "dropped data frame to not associated station %pM\n",
314 				   hdr->addr1);
315 #endif
316 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
317 			return TX_DROP;
318 		}
319 	} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
320 			    ieee80211_is_data(hdr->frame_control) &&
321 			    !atomic_read(&tx->sdata->u.ap.num_mcast_sta))) {
322 		/*
323 		 * No associated STAs - no need to send multicast
324 		 * frames.
325 		 */
326 		return TX_DROP;
327 	}
328 
329 	return TX_CONTINUE;
330 }
331 
332 /* This function is called whenever the AP is about to exceed the maximum limit
333  * of buffered frames for power saving STAs. This situation should not really
334  * happen often during normal operation, so dropping the oldest buffered packet
335  * from each queue should be OK to make some room for new frames. */
336 static void purge_old_ps_buffers(struct ieee80211_local *local)
337 {
338 	int total = 0, purged = 0;
339 	struct sk_buff *skb;
340 	struct ieee80211_sub_if_data *sdata;
341 	struct sta_info *sta;
342 
343 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
344 		struct ps_data *ps;
345 
346 		if (sdata->vif.type == NL80211_IFTYPE_AP)
347 			ps = &sdata->u.ap.ps;
348 		else if (ieee80211_vif_is_mesh(&sdata->vif))
349 			ps = &sdata->u.mesh.ps;
350 		else
351 			continue;
352 
353 		skb = skb_dequeue(&ps->bc_buf);
354 		if (skb) {
355 			purged++;
356 			dev_kfree_skb(skb);
357 		}
358 		total += skb_queue_len(&ps->bc_buf);
359 	}
360 
361 	/*
362 	 * Drop one frame from each station from the lowest-priority
363 	 * AC that has frames at all.
364 	 */
365 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
366 		int ac;
367 
368 		for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
369 			skb = skb_dequeue(&sta->ps_tx_buf[ac]);
370 			total += skb_queue_len(&sta->ps_tx_buf[ac]);
371 			if (skb) {
372 				purged++;
373 				ieee80211_free_txskb(&local->hw, skb);
374 				break;
375 			}
376 		}
377 	}
378 
379 	local->total_ps_buffered = total;
380 	ps_dbg_hw(&local->hw, "PS buffers full - purged %d frames\n", purged);
381 }
382 
383 static ieee80211_tx_result
384 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
385 {
386 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
387 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
388 	struct ps_data *ps;
389 
390 	/*
391 	 * broadcast/multicast frame
392 	 *
393 	 * If any of the associated/peer stations is in power save mode,
394 	 * the frame is buffered to be sent after DTIM beacon frame.
395 	 * This is done either by the hardware or us.
396 	 */
397 
398 	/* powersaving STAs currently only in AP/VLAN/mesh mode */
399 	if (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
400 	    tx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
401 		if (!tx->sdata->bss)
402 			return TX_CONTINUE;
403 
404 		ps = &tx->sdata->bss->ps;
405 	} else if (ieee80211_vif_is_mesh(&tx->sdata->vif)) {
406 		ps = &tx->sdata->u.mesh.ps;
407 	} else {
408 		return TX_CONTINUE;
409 	}
410 
411 
412 	/* no buffering for ordered frames */
413 	if (ieee80211_has_order(hdr->frame_control))
414 		return TX_CONTINUE;
415 
416 	if (tx->local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
417 		info->hw_queue = tx->sdata->vif.cab_queue;
418 
419 	/* no stations in PS mode */
420 	if (!atomic_read(&ps->num_sta_ps))
421 		return TX_CONTINUE;
422 
423 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
424 
425 	/* device releases frame after DTIM beacon */
426 	if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
427 		return TX_CONTINUE;
428 
429 	/* buffered in mac80211 */
430 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
431 		purge_old_ps_buffers(tx->local);
432 
433 	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
434 		ps_dbg(tx->sdata,
435 		       "BC TX buffer full - dropping the oldest frame\n");
436 		dev_kfree_skb(skb_dequeue(&ps->bc_buf));
437 	} else
438 		tx->local->total_ps_buffered++;
439 
440 	skb_queue_tail(&ps->bc_buf, tx->skb);
441 
442 	return TX_QUEUED;
443 }
444 
445 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
446 			     struct sk_buff *skb)
447 {
448 	if (!ieee80211_is_mgmt(fc))
449 		return 0;
450 
451 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
452 		return 0;
453 
454 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
455 					    skb->data))
456 		return 0;
457 
458 	return 1;
459 }
460 
461 static ieee80211_tx_result
462 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
463 {
464 	struct sta_info *sta = tx->sta;
465 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
466 	struct ieee80211_local *local = tx->local;
467 
468 	if (unlikely(!sta))
469 		return TX_CONTINUE;
470 
471 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
472 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER)) &&
473 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
474 		int ac = skb_get_queue_mapping(tx->skb);
475 
476 		ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
477 		       sta->sta.addr, sta->sta.aid, ac);
478 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
479 			purge_old_ps_buffers(tx->local);
480 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
481 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
482 			ps_dbg(tx->sdata,
483 			       "STA %pM TX buffer for AC %d full - dropping oldest frame\n",
484 			       sta->sta.addr, ac);
485 			ieee80211_free_txskb(&local->hw, old);
486 		} else
487 			tx->local->total_ps_buffered++;
488 
489 		info->control.jiffies = jiffies;
490 		info->control.vif = &tx->sdata->vif;
491 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
492 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
493 
494 		if (!timer_pending(&local->sta_cleanup))
495 			mod_timer(&local->sta_cleanup,
496 				  round_jiffies(jiffies +
497 						STA_INFO_CLEANUP_INTERVAL));
498 
499 		/*
500 		 * We queued up some frames, so the TIM bit might
501 		 * need to be set, recalculate it.
502 		 */
503 		sta_info_recalc_tim(sta);
504 
505 		return TX_QUEUED;
506 	} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
507 		ps_dbg(tx->sdata,
508 		       "STA %pM in PS mode, but polling/in SP -> send frame\n",
509 		       sta->sta.addr);
510 	}
511 
512 	return TX_CONTINUE;
513 }
514 
515 static ieee80211_tx_result debug_noinline
516 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
517 {
518 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
519 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
520 
521 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
522 		return TX_CONTINUE;
523 
524 	/* only deauth, disassoc and action are bufferable MMPDUs */
525 	if (ieee80211_is_mgmt(hdr->frame_control) &&
526 	    !ieee80211_is_deauth(hdr->frame_control) &&
527 	    !ieee80211_is_disassoc(hdr->frame_control) &&
528 	    !ieee80211_is_action(hdr->frame_control)) {
529 		if (tx->flags & IEEE80211_TX_UNICAST)
530 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
531 		return TX_CONTINUE;
532 	}
533 
534 	if (tx->flags & IEEE80211_TX_UNICAST)
535 		return ieee80211_tx_h_unicast_ps_buf(tx);
536 	else
537 		return ieee80211_tx_h_multicast_ps_buf(tx);
538 }
539 
540 static ieee80211_tx_result debug_noinline
541 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
542 {
543 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
544 
545 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol)) {
546 		if (tx->sdata->control_port_no_encrypt)
547 			info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
548 		info->control.flags |= IEEE80211_TX_CTRL_PORT_CTRL_PROTO;
549 	}
550 
551 	return TX_CONTINUE;
552 }
553 
554 static ieee80211_tx_result debug_noinline
555 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
556 {
557 	struct ieee80211_key *key;
558 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
559 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
560 
561 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
562 		tx->key = NULL;
563 	else if (tx->sta && (key = rcu_dereference(tx->sta->ptk)))
564 		tx->key = key;
565 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
566 		 is_multicast_ether_addr(hdr->addr1) &&
567 		 ieee80211_is_robust_mgmt_frame(hdr) &&
568 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
569 		tx->key = key;
570 	else if (is_multicast_ether_addr(hdr->addr1) &&
571 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
572 		tx->key = key;
573 	else if (!is_multicast_ether_addr(hdr->addr1) &&
574 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
575 		tx->key = key;
576 	else if (info->flags & IEEE80211_TX_CTL_INJECTED)
577 		tx->key = NULL;
578 	else if (!tx->sdata->drop_unencrypted)
579 		tx->key = NULL;
580 	else if (tx->skb->protocol == tx->sdata->control_port_protocol)
581 		tx->key = NULL;
582 	else if (ieee80211_is_robust_mgmt_frame(hdr) &&
583 		 !(ieee80211_is_action(hdr->frame_control) &&
584 		   tx->sta && test_sta_flag(tx->sta, WLAN_STA_MFP)))
585 		tx->key = NULL;
586 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
587 		 !ieee80211_is_robust_mgmt_frame(hdr))
588 		tx->key = NULL;
589 	else {
590 		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
591 		return TX_DROP;
592 	}
593 
594 	if (tx->key) {
595 		bool skip_hw = false;
596 
597 		tx->key->tx_rx_count++;
598 		/* TODO: add threshold stuff again */
599 
600 		switch (tx->key->conf.cipher) {
601 		case WLAN_CIPHER_SUITE_WEP40:
602 		case WLAN_CIPHER_SUITE_WEP104:
603 		case WLAN_CIPHER_SUITE_TKIP:
604 			if (!ieee80211_is_data_present(hdr->frame_control))
605 				tx->key = NULL;
606 			break;
607 		case WLAN_CIPHER_SUITE_CCMP:
608 			if (!ieee80211_is_data_present(hdr->frame_control) &&
609 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
610 					       tx->skb))
611 				tx->key = NULL;
612 			else
613 				skip_hw = (tx->key->conf.flags &
614 					   IEEE80211_KEY_FLAG_SW_MGMT_TX) &&
615 					ieee80211_is_mgmt(hdr->frame_control);
616 			break;
617 		case WLAN_CIPHER_SUITE_AES_CMAC:
618 			if (!ieee80211_is_mgmt(hdr->frame_control))
619 				tx->key = NULL;
620 			break;
621 		}
622 
623 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED &&
624 			     !ieee80211_is_deauth(hdr->frame_control)))
625 			return TX_DROP;
626 
627 		if (!skip_hw && tx->key &&
628 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
629 			info->control.hw_key = &tx->key->conf;
630 	}
631 
632 	return TX_CONTINUE;
633 }
634 
635 static ieee80211_tx_result debug_noinline
636 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
637 {
638 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
639 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
640 	struct ieee80211_supported_band *sband;
641 	u32 len;
642 	struct ieee80211_tx_rate_control txrc;
643 	struct ieee80211_sta_rates *ratetbl = NULL;
644 	bool assoc = false;
645 
646 	memset(&txrc, 0, sizeof(txrc));
647 
648 	sband = tx->local->hw.wiphy->bands[info->band];
649 
650 	len = min_t(u32, tx->skb->len + FCS_LEN,
651 			 tx->local->hw.wiphy->frag_threshold);
652 
653 	/* set up the tx rate control struct we give the RC algo */
654 	txrc.hw = &tx->local->hw;
655 	txrc.sband = sband;
656 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
657 	txrc.skb = tx->skb;
658 	txrc.reported_rate.idx = -1;
659 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
660 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
661 		txrc.max_rate_idx = -1;
662 	else
663 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
664 
665 	if (tx->sdata->rc_has_mcs_mask[info->band])
666 		txrc.rate_idx_mcs_mask =
667 			tx->sdata->rc_rateidx_mcs_mask[info->band];
668 
669 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
670 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
671 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
672 
673 	/* set up RTS protection if desired */
674 	if (len > tx->local->hw.wiphy->rts_threshold) {
675 		txrc.rts = true;
676 	}
677 
678 	info->control.use_rts = txrc.rts;
679 	info->control.use_cts_prot = tx->sdata->vif.bss_conf.use_cts_prot;
680 
681 	/*
682 	 * Use short preamble if the BSS can handle it, but not for
683 	 * management frames unless we know the receiver can handle
684 	 * that -- the management frame might be to a station that
685 	 * just wants a probe response.
686 	 */
687 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
688 	    (ieee80211_is_data(hdr->frame_control) ||
689 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
690 		txrc.short_preamble = true;
691 
692 	info->control.short_preamble = txrc.short_preamble;
693 
694 	if (tx->sta)
695 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
696 
697 	/*
698 	 * Lets not bother rate control if we're associated and cannot
699 	 * talk to the sta. This should not happen.
700 	 */
701 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
702 		 !rate_usable_index_exists(sband, &tx->sta->sta),
703 		 "%s: Dropped data frame as no usable bitrate found while "
704 		 "scanning and associated. Target station: "
705 		 "%pM on %d GHz band\n",
706 		 tx->sdata->name, hdr->addr1,
707 		 info->band ? 5 : 2))
708 		return TX_DROP;
709 
710 	/*
711 	 * If we're associated with the sta at this point we know we can at
712 	 * least send the frame at the lowest bit rate.
713 	 */
714 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
715 
716 	if (tx->sta && !info->control.skip_table)
717 		ratetbl = rcu_dereference(tx->sta->sta.rates);
718 
719 	if (unlikely(info->control.rates[0].idx < 0)) {
720 		if (ratetbl) {
721 			struct ieee80211_tx_rate rate = {
722 				.idx = ratetbl->rate[0].idx,
723 				.flags = ratetbl->rate[0].flags,
724 				.count = ratetbl->rate[0].count
725 			};
726 
727 			if (ratetbl->rate[0].idx < 0)
728 				return TX_DROP;
729 
730 			tx->rate = rate;
731 		} else {
732 			return TX_DROP;
733 		}
734 	} else {
735 		tx->rate = info->control.rates[0];
736 	}
737 
738 	if (txrc.reported_rate.idx < 0) {
739 		txrc.reported_rate = tx->rate;
740 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
741 			tx->sta->last_tx_rate = txrc.reported_rate;
742 	} else if (tx->sta)
743 		tx->sta->last_tx_rate = txrc.reported_rate;
744 
745 	if (ratetbl)
746 		return TX_CONTINUE;
747 
748 	if (unlikely(!info->control.rates[0].count))
749 		info->control.rates[0].count = 1;
750 
751 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
752 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
753 		info->control.rates[0].count = 1;
754 
755 	return TX_CONTINUE;
756 }
757 
758 static ieee80211_tx_result debug_noinline
759 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
760 {
761 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
762 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
763 	u16 *seq;
764 	u8 *qc;
765 	int tid;
766 
767 	/*
768 	 * Packet injection may want to control the sequence
769 	 * number, if we have no matching interface then we
770 	 * neither assign one ourselves nor ask the driver to.
771 	 */
772 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
773 		return TX_CONTINUE;
774 
775 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
776 		return TX_CONTINUE;
777 
778 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
779 		return TX_CONTINUE;
780 
781 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
782 		return TX_CONTINUE;
783 
784 	/*
785 	 * Anything but QoS data that has a sequence number field
786 	 * (is long enough) gets a sequence number from the global
787 	 * counter.  QoS data frames with a multicast destination
788 	 * also use the global counter (802.11-2012 9.3.2.10).
789 	 */
790 	if (!ieee80211_is_data_qos(hdr->frame_control) ||
791 	    is_multicast_ether_addr(hdr->addr1)) {
792 		/* driver should assign sequence number */
793 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
794 		/* for pure STA mode without beacons, we can do it */
795 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
796 		tx->sdata->sequence_number += 0x10;
797 		return TX_CONTINUE;
798 	}
799 
800 	/*
801 	 * This should be true for injected/management frames only, for
802 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
803 	 * above since they are not QoS-data frames.
804 	 */
805 	if (!tx->sta)
806 		return TX_CONTINUE;
807 
808 	/* include per-STA, per-TID sequence counter */
809 
810 	qc = ieee80211_get_qos_ctl(hdr);
811 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
812 	seq = &tx->sta->tid_seq[tid];
813 
814 	hdr->seq_ctrl = cpu_to_le16(*seq);
815 
816 	/* Increase the sequence number. */
817 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
818 
819 	return TX_CONTINUE;
820 }
821 
822 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
823 			      struct sk_buff *skb, int hdrlen,
824 			      int frag_threshold)
825 {
826 	struct ieee80211_local *local = tx->local;
827 	struct ieee80211_tx_info *info;
828 	struct sk_buff *tmp;
829 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
830 	int pos = hdrlen + per_fragm;
831 	int rem = skb->len - hdrlen - per_fragm;
832 
833 	if (WARN_ON(rem < 0))
834 		return -EINVAL;
835 
836 	/* first fragment was already added to queue by caller */
837 
838 	while (rem) {
839 		int fraglen = per_fragm;
840 
841 		if (fraglen > rem)
842 			fraglen = rem;
843 		rem -= fraglen;
844 		tmp = dev_alloc_skb(local->tx_headroom +
845 				    frag_threshold +
846 				    IEEE80211_ENCRYPT_HEADROOM +
847 				    IEEE80211_ENCRYPT_TAILROOM);
848 		if (!tmp)
849 			return -ENOMEM;
850 
851 		__skb_queue_tail(&tx->skbs, tmp);
852 
853 		skb_reserve(tmp, local->tx_headroom +
854 				 IEEE80211_ENCRYPT_HEADROOM);
855 		/* copy control information */
856 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
857 
858 		info = IEEE80211_SKB_CB(tmp);
859 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
860 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
861 
862 		if (rem)
863 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
864 
865 		skb_copy_queue_mapping(tmp, skb);
866 		tmp->priority = skb->priority;
867 		tmp->dev = skb->dev;
868 
869 		/* copy header and data */
870 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
871 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
872 
873 		pos += fraglen;
874 	}
875 
876 	/* adjust first fragment's length */
877 	skb->len = hdrlen + per_fragm;
878 	return 0;
879 }
880 
881 static ieee80211_tx_result debug_noinline
882 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
883 {
884 	struct sk_buff *skb = tx->skb;
885 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
886 	struct ieee80211_hdr *hdr = (void *)skb->data;
887 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
888 	int hdrlen;
889 	int fragnum;
890 
891 	/* no matter what happens, tx->skb moves to tx->skbs */
892 	__skb_queue_tail(&tx->skbs, skb);
893 	tx->skb = NULL;
894 
895 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
896 		return TX_CONTINUE;
897 
898 	if (tx->local->ops->set_frag_threshold)
899 		return TX_CONTINUE;
900 
901 	/*
902 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
903 	 * This scenario is handled in ieee80211_tx_prepare but extra
904 	 * caution taken here as fragmented ampdu may cause Tx stop.
905 	 */
906 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
907 		return TX_DROP;
908 
909 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
910 
911 	/* internal error, why isn't DONTFRAG set? */
912 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
913 		return TX_DROP;
914 
915 	/*
916 	 * Now fragment the frame. This will allocate all the fragments and
917 	 * chain them (using skb as the first fragment) to skb->next.
918 	 * During transmission, we will remove the successfully transmitted
919 	 * fragments from this list. When the low-level driver rejects one
920 	 * of the fragments then we will simply pretend to accept the skb
921 	 * but store it away as pending.
922 	 */
923 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
924 		return TX_DROP;
925 
926 	/* update duration/seq/flags of fragments */
927 	fragnum = 0;
928 
929 	skb_queue_walk(&tx->skbs, skb) {
930 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
931 
932 		hdr = (void *)skb->data;
933 		info = IEEE80211_SKB_CB(skb);
934 
935 		if (!skb_queue_is_last(&tx->skbs, skb)) {
936 			hdr->frame_control |= morefrags;
937 			/*
938 			 * No multi-rate retries for fragmented frames, that
939 			 * would completely throw off the NAV at other STAs.
940 			 */
941 			info->control.rates[1].idx = -1;
942 			info->control.rates[2].idx = -1;
943 			info->control.rates[3].idx = -1;
944 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 4);
945 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
946 		} else {
947 			hdr->frame_control &= ~morefrags;
948 		}
949 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
950 		fragnum++;
951 	}
952 
953 	return TX_CONTINUE;
954 }
955 
956 static ieee80211_tx_result debug_noinline
957 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
958 {
959 	struct sk_buff *skb;
960 	int ac = -1;
961 
962 	if (!tx->sta)
963 		return TX_CONTINUE;
964 
965 	skb_queue_walk(&tx->skbs, skb) {
966 		ac = skb_get_queue_mapping(skb);
967 		tx->sta->tx_fragments++;
968 		tx->sta->tx_bytes[ac] += skb->len;
969 	}
970 	if (ac >= 0)
971 		tx->sta->tx_packets[ac]++;
972 
973 	return TX_CONTINUE;
974 }
975 
976 static ieee80211_tx_result debug_noinline
977 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
978 {
979 	if (!tx->key)
980 		return TX_CONTINUE;
981 
982 	switch (tx->key->conf.cipher) {
983 	case WLAN_CIPHER_SUITE_WEP40:
984 	case WLAN_CIPHER_SUITE_WEP104:
985 		return ieee80211_crypto_wep_encrypt(tx);
986 	case WLAN_CIPHER_SUITE_TKIP:
987 		return ieee80211_crypto_tkip_encrypt(tx);
988 	case WLAN_CIPHER_SUITE_CCMP:
989 		return ieee80211_crypto_ccmp_encrypt(tx);
990 	case WLAN_CIPHER_SUITE_AES_CMAC:
991 		return ieee80211_crypto_aes_cmac_encrypt(tx);
992 	default:
993 		return ieee80211_crypto_hw_encrypt(tx);
994 	}
995 
996 	return TX_DROP;
997 }
998 
999 static ieee80211_tx_result debug_noinline
1000 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
1001 {
1002 	struct sk_buff *skb;
1003 	struct ieee80211_hdr *hdr;
1004 	int next_len;
1005 	bool group_addr;
1006 
1007 	skb_queue_walk(&tx->skbs, skb) {
1008 		hdr = (void *) skb->data;
1009 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
1010 			break; /* must not overwrite AID */
1011 		if (!skb_queue_is_last(&tx->skbs, skb)) {
1012 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
1013 			next_len = next->len;
1014 		} else
1015 			next_len = 0;
1016 		group_addr = is_multicast_ether_addr(hdr->addr1);
1017 
1018 		hdr->duration_id =
1019 			ieee80211_duration(tx, skb, group_addr, next_len);
1020 	}
1021 
1022 	return TX_CONTINUE;
1023 }
1024 
1025 /* actual transmit path */
1026 
1027 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1028 				  struct sk_buff *skb,
1029 				  struct ieee80211_tx_info *info,
1030 				  struct tid_ampdu_tx *tid_tx,
1031 				  int tid)
1032 {
1033 	bool queued = false;
1034 	bool reset_agg_timer = false;
1035 	struct sk_buff *purge_skb = NULL;
1036 
1037 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1038 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1039 		reset_agg_timer = true;
1040 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1041 		/*
1042 		 * nothing -- this aggregation session is being started
1043 		 * but that might still fail with the driver
1044 		 */
1045 	} else {
1046 		spin_lock(&tx->sta->lock);
1047 		/*
1048 		 * Need to re-check now, because we may get here
1049 		 *
1050 		 *  1) in the window during which the setup is actually
1051 		 *     already done, but not marked yet because not all
1052 		 *     packets are spliced over to the driver pending
1053 		 *     queue yet -- if this happened we acquire the lock
1054 		 *     either before or after the splice happens, but
1055 		 *     need to recheck which of these cases happened.
1056 		 *
1057 		 *  2) during session teardown, if the OPERATIONAL bit
1058 		 *     was cleared due to the teardown but the pointer
1059 		 *     hasn't been assigned NULL yet (or we loaded it
1060 		 *     before it was assigned) -- in this case it may
1061 		 *     now be NULL which means we should just let the
1062 		 *     packet pass through because splicing the frames
1063 		 *     back is already done.
1064 		 */
1065 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1066 
1067 		if (!tid_tx) {
1068 			/* do nothing, let packet pass through */
1069 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1070 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1071 			reset_agg_timer = true;
1072 		} else {
1073 			queued = true;
1074 			info->control.vif = &tx->sdata->vif;
1075 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1076 			__skb_queue_tail(&tid_tx->pending, skb);
1077 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1078 				purge_skb = __skb_dequeue(&tid_tx->pending);
1079 		}
1080 		spin_unlock(&tx->sta->lock);
1081 
1082 		if (purge_skb)
1083 			ieee80211_free_txskb(&tx->local->hw, purge_skb);
1084 	}
1085 
1086 	/* reset session timer */
1087 	if (reset_agg_timer && tid_tx->timeout)
1088 		tid_tx->last_tx = jiffies;
1089 
1090 	return queued;
1091 }
1092 
1093 /*
1094  * initialises @tx
1095  */
1096 static ieee80211_tx_result
1097 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1098 		     struct ieee80211_tx_data *tx,
1099 		     struct sk_buff *skb)
1100 {
1101 	struct ieee80211_local *local = sdata->local;
1102 	struct ieee80211_hdr *hdr;
1103 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1104 	int tid;
1105 	u8 *qc;
1106 
1107 	memset(tx, 0, sizeof(*tx));
1108 	tx->skb = skb;
1109 	tx->local = local;
1110 	tx->sdata = sdata;
1111 	__skb_queue_head_init(&tx->skbs);
1112 
1113 	/*
1114 	 * If this flag is set to true anywhere, and we get here,
1115 	 * we are doing the needed processing, so remove the flag
1116 	 * now.
1117 	 */
1118 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1119 
1120 	hdr = (struct ieee80211_hdr *) skb->data;
1121 
1122 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1123 		tx->sta = rcu_dereference(sdata->u.vlan.sta);
1124 		if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
1125 			return TX_DROP;
1126 	} else if (info->flags & (IEEE80211_TX_CTL_INJECTED |
1127 				  IEEE80211_TX_INTFL_NL80211_FRAME_TX) ||
1128 		   tx->sdata->control_port_protocol == tx->skb->protocol) {
1129 		tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1130 	}
1131 	if (!tx->sta)
1132 		tx->sta = sta_info_get(sdata, hdr->addr1);
1133 
1134 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1135 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1136 	    (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) &&
1137 	    !(local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) {
1138 		struct tid_ampdu_tx *tid_tx;
1139 
1140 		qc = ieee80211_get_qos_ctl(hdr);
1141 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1142 
1143 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1144 		if (tid_tx) {
1145 			bool queued;
1146 
1147 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1148 						       tid_tx, tid);
1149 
1150 			if (unlikely(queued))
1151 				return TX_QUEUED;
1152 		}
1153 	}
1154 
1155 	if (is_multicast_ether_addr(hdr->addr1)) {
1156 		tx->flags &= ~IEEE80211_TX_UNICAST;
1157 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1158 	} else
1159 		tx->flags |= IEEE80211_TX_UNICAST;
1160 
1161 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1162 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1163 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1164 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1165 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1166 	}
1167 
1168 	if (!tx->sta)
1169 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1170 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1171 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1172 
1173 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1174 
1175 	return TX_CONTINUE;
1176 }
1177 
1178 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1179 			       struct ieee80211_vif *vif,
1180 			       struct ieee80211_sta *sta,
1181 			       struct sk_buff_head *skbs,
1182 			       bool txpending)
1183 {
1184 	struct ieee80211_tx_control control;
1185 	struct sk_buff *skb, *tmp;
1186 	unsigned long flags;
1187 
1188 	skb_queue_walk_safe(skbs, skb, tmp) {
1189 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1190 		int q = info->hw_queue;
1191 
1192 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1193 		if (WARN_ON_ONCE(q >= local->hw.queues)) {
1194 			__skb_unlink(skb, skbs);
1195 			ieee80211_free_txskb(&local->hw, skb);
1196 			continue;
1197 		}
1198 #endif
1199 
1200 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1201 		if (local->queue_stop_reasons[q] ||
1202 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1203 			if (unlikely(info->flags &
1204 				     IEEE80211_TX_INTFL_OFFCHAN_TX_OK)) {
1205 				if (local->queue_stop_reasons[q] &
1206 				    ~BIT(IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL)) {
1207 					/*
1208 					 * Drop off-channel frames if queues
1209 					 * are stopped for any reason other
1210 					 * than off-channel operation. Never
1211 					 * queue them.
1212 					 */
1213 					spin_unlock_irqrestore(
1214 						&local->queue_stop_reason_lock,
1215 						flags);
1216 					ieee80211_purge_tx_queue(&local->hw,
1217 								 skbs);
1218 					return true;
1219 				}
1220 			} else {
1221 
1222 				/*
1223 				 * Since queue is stopped, queue up frames for
1224 				 * later transmission from the tx-pending
1225 				 * tasklet when the queue is woken again.
1226 				 */
1227 				if (txpending)
1228 					skb_queue_splice_init(skbs,
1229 							      &local->pending[q]);
1230 				else
1231 					skb_queue_splice_tail_init(skbs,
1232 								   &local->pending[q]);
1233 
1234 				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1235 						       flags);
1236 				return false;
1237 			}
1238 		}
1239 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1240 
1241 		info->control.vif = vif;
1242 		control.sta = sta;
1243 
1244 		__skb_unlink(skb, skbs);
1245 		drv_tx(local, &control, skb);
1246 	}
1247 
1248 	return true;
1249 }
1250 
1251 /*
1252  * Returns false if the frame couldn't be transmitted but was queued instead.
1253  */
1254 static bool __ieee80211_tx(struct ieee80211_local *local,
1255 			   struct sk_buff_head *skbs, int led_len,
1256 			   struct sta_info *sta, bool txpending)
1257 {
1258 	struct ieee80211_tx_info *info;
1259 	struct ieee80211_sub_if_data *sdata;
1260 	struct ieee80211_vif *vif;
1261 	struct ieee80211_sta *pubsta;
1262 	struct sk_buff *skb;
1263 	bool result = true;
1264 	__le16 fc;
1265 
1266 	if (WARN_ON(skb_queue_empty(skbs)))
1267 		return true;
1268 
1269 	skb = skb_peek(skbs);
1270 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1271 	info = IEEE80211_SKB_CB(skb);
1272 	sdata = vif_to_sdata(info->control.vif);
1273 	if (sta && !sta->uploaded)
1274 		sta = NULL;
1275 
1276 	if (sta)
1277 		pubsta = &sta->sta;
1278 	else
1279 		pubsta = NULL;
1280 
1281 	switch (sdata->vif.type) {
1282 	case NL80211_IFTYPE_MONITOR:
1283 		if (sdata->u.mntr_flags & MONITOR_FLAG_ACTIVE) {
1284 			vif = &sdata->vif;
1285 			break;
1286 		}
1287 		sdata = rcu_dereference(local->monitor_sdata);
1288 		if (sdata) {
1289 			vif = &sdata->vif;
1290 			info->hw_queue =
1291 				vif->hw_queue[skb_get_queue_mapping(skb)];
1292 		} else if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL) {
1293 			dev_kfree_skb(skb);
1294 			return true;
1295 		} else
1296 			vif = NULL;
1297 		break;
1298 	case NL80211_IFTYPE_AP_VLAN:
1299 		sdata = container_of(sdata->bss,
1300 				     struct ieee80211_sub_if_data, u.ap);
1301 		/* fall through */
1302 	default:
1303 		vif = &sdata->vif;
1304 		break;
1305 	}
1306 
1307 	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1308 				    txpending);
1309 
1310 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1311 
1312 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1313 
1314 	return result;
1315 }
1316 
1317 /*
1318  * Invoke TX handlers, return 0 on success and non-zero if the
1319  * frame was dropped or queued.
1320  */
1321 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1322 {
1323 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1324 	ieee80211_tx_result res = TX_DROP;
1325 
1326 #define CALL_TXH(txh) \
1327 	do {				\
1328 		res = txh(tx);		\
1329 		if (res != TX_CONTINUE)	\
1330 			goto txh_done;	\
1331 	} while (0)
1332 
1333 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1334 	CALL_TXH(ieee80211_tx_h_check_assoc);
1335 	CALL_TXH(ieee80211_tx_h_ps_buf);
1336 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1337 	CALL_TXH(ieee80211_tx_h_select_key);
1338 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1339 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1340 
1341 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1342 		__skb_queue_tail(&tx->skbs, tx->skb);
1343 		tx->skb = NULL;
1344 		goto txh_done;
1345 	}
1346 
1347 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1348 	CALL_TXH(ieee80211_tx_h_sequence);
1349 	CALL_TXH(ieee80211_tx_h_fragment);
1350 	/* handlers after fragment must be aware of tx info fragmentation! */
1351 	CALL_TXH(ieee80211_tx_h_stats);
1352 	CALL_TXH(ieee80211_tx_h_encrypt);
1353 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1354 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1355 #undef CALL_TXH
1356 
1357  txh_done:
1358 	if (unlikely(res == TX_DROP)) {
1359 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1360 		if (tx->skb)
1361 			ieee80211_free_txskb(&tx->local->hw, tx->skb);
1362 		else
1363 			ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
1364 		return -1;
1365 	} else if (unlikely(res == TX_QUEUED)) {
1366 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1367 		return -1;
1368 	}
1369 
1370 	return 0;
1371 }
1372 
1373 bool ieee80211_tx_prepare_skb(struct ieee80211_hw *hw,
1374 			      struct ieee80211_vif *vif, struct sk_buff *skb,
1375 			      int band, struct ieee80211_sta **sta)
1376 {
1377 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1378 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1379 	struct ieee80211_tx_data tx;
1380 
1381 	if (ieee80211_tx_prepare(sdata, &tx, skb) == TX_DROP)
1382 		return false;
1383 
1384 	info->band = band;
1385 	info->control.vif = vif;
1386 	info->hw_queue = vif->hw_queue[skb_get_queue_mapping(skb)];
1387 
1388 	if (invoke_tx_handlers(&tx))
1389 		return false;
1390 
1391 	if (sta) {
1392 		if (tx.sta)
1393 			*sta = &tx.sta->sta;
1394 		else
1395 			*sta = NULL;
1396 	}
1397 
1398 	return true;
1399 }
1400 EXPORT_SYMBOL(ieee80211_tx_prepare_skb);
1401 
1402 /*
1403  * Returns false if the frame couldn't be transmitted but was queued instead.
1404  */
1405 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1406 			 struct sk_buff *skb, bool txpending,
1407 			 enum ieee80211_band band)
1408 {
1409 	struct ieee80211_local *local = sdata->local;
1410 	struct ieee80211_tx_data tx;
1411 	ieee80211_tx_result res_prepare;
1412 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1413 	bool result = true;
1414 	int led_len;
1415 
1416 	if (unlikely(skb->len < 10)) {
1417 		dev_kfree_skb(skb);
1418 		return true;
1419 	}
1420 
1421 	/* initialises tx */
1422 	led_len = skb->len;
1423 	res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1424 
1425 	if (unlikely(res_prepare == TX_DROP)) {
1426 		ieee80211_free_txskb(&local->hw, skb);
1427 		return true;
1428 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1429 		return true;
1430 	}
1431 
1432 	info->band = band;
1433 
1434 	/* set up hw_queue value early */
1435 	if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
1436 	    !(local->hw.flags & IEEE80211_HW_QUEUE_CONTROL))
1437 		info->hw_queue =
1438 			sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
1439 
1440 	if (!invoke_tx_handlers(&tx))
1441 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1442 					tx.sta, txpending);
1443 
1444 	return result;
1445 }
1446 
1447 /* device xmit handlers */
1448 
1449 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1450 				struct sk_buff *skb,
1451 				int head_need, bool may_encrypt)
1452 {
1453 	struct ieee80211_local *local = sdata->local;
1454 	int tail_need = 0;
1455 
1456 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1457 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1458 		tail_need -= skb_tailroom(skb);
1459 		tail_need = max_t(int, tail_need, 0);
1460 	}
1461 
1462 	if (skb_cloned(skb))
1463 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1464 	else if (head_need || tail_need)
1465 		I802_DEBUG_INC(local->tx_expand_skb_head);
1466 	else
1467 		return 0;
1468 
1469 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1470 		wiphy_debug(local->hw.wiphy,
1471 			    "failed to reallocate TX buffer\n");
1472 		return -ENOMEM;
1473 	}
1474 
1475 	return 0;
1476 }
1477 
1478 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
1479 		    enum ieee80211_band band)
1480 {
1481 	struct ieee80211_local *local = sdata->local;
1482 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1483 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1484 	int headroom;
1485 	bool may_encrypt;
1486 
1487 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1488 
1489 	headroom = local->tx_headroom;
1490 	if (may_encrypt)
1491 		headroom += IEEE80211_ENCRYPT_HEADROOM;
1492 	headroom -= skb_headroom(skb);
1493 	headroom = max_t(int, 0, headroom);
1494 
1495 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1496 		ieee80211_free_txskb(&local->hw, skb);
1497 		return;
1498 	}
1499 
1500 	hdr = (struct ieee80211_hdr *) skb->data;
1501 	info->control.vif = &sdata->vif;
1502 
1503 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1504 		if (ieee80211_is_data(hdr->frame_control) &&
1505 		    is_unicast_ether_addr(hdr->addr1)) {
1506 			if (mesh_nexthop_resolve(sdata, skb))
1507 				return; /* skb queued: don't free */
1508 		} else {
1509 			ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
1510 		}
1511 	}
1512 
1513 	ieee80211_set_qos_hdr(sdata, skb);
1514 	ieee80211_tx(sdata, skb, false, band);
1515 }
1516 
1517 static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
1518 {
1519 	struct ieee80211_radiotap_iterator iterator;
1520 	struct ieee80211_radiotap_header *rthdr =
1521 		(struct ieee80211_radiotap_header *) skb->data;
1522 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1523 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1524 						   NULL);
1525 	u16 txflags;
1526 
1527 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1528 		       IEEE80211_TX_CTL_DONTFRAG;
1529 
1530 	/*
1531 	 * for every radiotap entry that is present
1532 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1533 	 * entries present, or -EINVAL on error)
1534 	 */
1535 
1536 	while (!ret) {
1537 		ret = ieee80211_radiotap_iterator_next(&iterator);
1538 
1539 		if (ret)
1540 			continue;
1541 
1542 		/* see if this argument is something we can use */
1543 		switch (iterator.this_arg_index) {
1544 		/*
1545 		 * You must take care when dereferencing iterator.this_arg
1546 		 * for multibyte types... the pointer is not aligned.  Use
1547 		 * get_unaligned((type *)iterator.this_arg) to dereference
1548 		 * iterator.this_arg for type "type" safely on all arches.
1549 		*/
1550 		case IEEE80211_RADIOTAP_FLAGS:
1551 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1552 				/*
1553 				 * this indicates that the skb we have been
1554 				 * handed has the 32-bit FCS CRC at the end...
1555 				 * we should react to that by snipping it off
1556 				 * because it will be recomputed and added
1557 				 * on transmission
1558 				 */
1559 				if (skb->len < (iterator._max_length + FCS_LEN))
1560 					return false;
1561 
1562 				skb_trim(skb, skb->len - FCS_LEN);
1563 			}
1564 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1565 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1566 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1567 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1568 			break;
1569 
1570 		case IEEE80211_RADIOTAP_TX_FLAGS:
1571 			txflags = get_unaligned_le16(iterator.this_arg);
1572 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1573 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1574 			break;
1575 
1576 		/*
1577 		 * Please update the file
1578 		 * Documentation/networking/mac80211-injection.txt
1579 		 * when parsing new fields here.
1580 		 */
1581 
1582 		default:
1583 			break;
1584 		}
1585 	}
1586 
1587 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1588 		return false;
1589 
1590 	/*
1591 	 * remove the radiotap header
1592 	 * iterator->_max_length was sanity-checked against
1593 	 * skb->len by iterator init
1594 	 */
1595 	skb_pull(skb, iterator._max_length);
1596 
1597 	return true;
1598 }
1599 
1600 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1601 					 struct net_device *dev)
1602 {
1603 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1604 	struct ieee80211_chanctx_conf *chanctx_conf;
1605 	struct ieee80211_channel *chan;
1606 	struct ieee80211_radiotap_header *prthdr =
1607 		(struct ieee80211_radiotap_header *)skb->data;
1608 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1609 	struct ieee80211_hdr *hdr;
1610 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1611 	u16 len_rthdr;
1612 	int hdrlen;
1613 
1614 	/* check for not even having the fixed radiotap header part */
1615 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1616 		goto fail; /* too short to be possibly valid */
1617 
1618 	/* is it a header version we can trust to find length from? */
1619 	if (unlikely(prthdr->it_version))
1620 		goto fail; /* only version 0 is supported */
1621 
1622 	/* then there must be a radiotap header with a length we can use */
1623 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1624 
1625 	/* does the skb contain enough to deliver on the alleged length? */
1626 	if (unlikely(skb->len < len_rthdr))
1627 		goto fail; /* skb too short for claimed rt header extent */
1628 
1629 	/*
1630 	 * fix up the pointers accounting for the radiotap
1631 	 * header still being in there.  We are being given
1632 	 * a precooked IEEE80211 header so no need for
1633 	 * normal processing
1634 	 */
1635 	skb_set_mac_header(skb, len_rthdr);
1636 	/*
1637 	 * these are just fixed to the end of the rt area since we
1638 	 * don't have any better information and at this point, nobody cares
1639 	 */
1640 	skb_set_network_header(skb, len_rthdr);
1641 	skb_set_transport_header(skb, len_rthdr);
1642 
1643 	if (skb->len < len_rthdr + 2)
1644 		goto fail;
1645 
1646 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1647 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1648 
1649 	if (skb->len < len_rthdr + hdrlen)
1650 		goto fail;
1651 
1652 	/*
1653 	 * Initialize skb->protocol if the injected frame is a data frame
1654 	 * carrying a rfc1042 header
1655 	 */
1656 	if (ieee80211_is_data(hdr->frame_control) &&
1657 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1658 		u8 *payload = (u8 *)hdr + hdrlen;
1659 
1660 		if (ether_addr_equal(payload, rfc1042_header))
1661 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1662 						    payload[7]);
1663 	}
1664 
1665 	memset(info, 0, sizeof(*info));
1666 
1667 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1668 		      IEEE80211_TX_CTL_INJECTED;
1669 
1670 	/* process and remove the injection radiotap header */
1671 	if (!ieee80211_parse_tx_radiotap(skb))
1672 		goto fail;
1673 
1674 	rcu_read_lock();
1675 
1676 	/*
1677 	 * We process outgoing injected frames that have a local address
1678 	 * we handle as though they are non-injected frames.
1679 	 * This code here isn't entirely correct, the local MAC address
1680 	 * isn't always enough to find the interface to use; for proper
1681 	 * VLAN/WDS support we will need a different mechanism (which
1682 	 * likely isn't going to be monitor interfaces).
1683 	 */
1684 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1685 
1686 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1687 		if (!ieee80211_sdata_running(tmp_sdata))
1688 			continue;
1689 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1690 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1691 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1692 			continue;
1693 		if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
1694 			sdata = tmp_sdata;
1695 			break;
1696 		}
1697 	}
1698 
1699 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1700 	if (!chanctx_conf) {
1701 		tmp_sdata = rcu_dereference(local->monitor_sdata);
1702 		if (tmp_sdata)
1703 			chanctx_conf =
1704 				rcu_dereference(tmp_sdata->vif.chanctx_conf);
1705 	}
1706 
1707 	if (chanctx_conf)
1708 		chan = chanctx_conf->def.chan;
1709 	else if (!local->use_chanctx)
1710 		chan = local->_oper_chandef.chan;
1711 	else
1712 		goto fail_rcu;
1713 
1714 	/*
1715 	 * Frame injection is not allowed if beaconing is not allowed
1716 	 * or if we need radar detection. Beaconing is usually not allowed when
1717 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1718 	 * Passive scan is also used in world regulatory domains where
1719 	 * your country is not known and as such it should be treated as
1720 	 * NO TX unless the channel is explicitly allowed in which case
1721 	 * your current regulatory domain would not have the passive scan
1722 	 * flag.
1723 	 *
1724 	 * Since AP mode uses monitor interfaces to inject/TX management
1725 	 * frames we can make AP mode the exception to this rule once it
1726 	 * supports radar detection as its implementation can deal with
1727 	 * radar detection by itself. We can do that later by adding a
1728 	 * monitor flag interfaces used for AP support.
1729 	 */
1730 	if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1731 			    IEEE80211_CHAN_PASSIVE_SCAN)))
1732 		goto fail_rcu;
1733 
1734 	ieee80211_xmit(sdata, skb, chan->band);
1735 	rcu_read_unlock();
1736 
1737 	return NETDEV_TX_OK;
1738 
1739 fail_rcu:
1740 	rcu_read_unlock();
1741 fail:
1742 	dev_kfree_skb(skb);
1743 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1744 }
1745 
1746 /**
1747  * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1748  * subinterfaces (wlan#, WDS, and VLAN interfaces)
1749  * @skb: packet to be sent
1750  * @dev: incoming interface
1751  *
1752  * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1753  * not be freed, and caller is responsible for either retrying later or freeing
1754  * skb).
1755  *
1756  * This function takes in an Ethernet header and encapsulates it with suitable
1757  * IEEE 802.11 header based on which interface the packet is coming in. The
1758  * encapsulated packet will then be passed to master interface, wlan#.11, for
1759  * transmission (through low-level driver).
1760  */
1761 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1762 				    struct net_device *dev)
1763 {
1764 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1765 	struct ieee80211_local *local = sdata->local;
1766 	struct ieee80211_tx_info *info;
1767 	int head_need;
1768 	u16 ethertype, hdrlen,  meshhdrlen = 0;
1769 	__le16 fc;
1770 	struct ieee80211_hdr hdr;
1771 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
1772 	struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
1773 	const u8 *encaps_data;
1774 	int encaps_len, skip_header_bytes;
1775 	int nh_pos, h_pos;
1776 	struct sta_info *sta = NULL;
1777 	bool wme_sta = false, authorized = false, tdls_auth = false;
1778 	bool tdls_direct = false;
1779 	bool multicast;
1780 	u32 info_flags = 0;
1781 	u16 info_id = 0;
1782 	struct ieee80211_chanctx_conf *chanctx_conf;
1783 	struct ieee80211_sub_if_data *ap_sdata;
1784 	enum ieee80211_band band;
1785 
1786 	if (unlikely(skb->len < ETH_HLEN))
1787 		goto fail;
1788 
1789 	/* convert Ethernet header to proper 802.11 header (based on
1790 	 * operation mode) */
1791 	ethertype = (skb->data[12] << 8) | skb->data[13];
1792 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1793 
1794 	rcu_read_lock();
1795 
1796 	switch (sdata->vif.type) {
1797 	case NL80211_IFTYPE_AP_VLAN:
1798 		sta = rcu_dereference(sdata->u.vlan.sta);
1799 		if (sta) {
1800 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1801 			/* RA TA DA SA */
1802 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
1803 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1804 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1805 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1806 			hdrlen = 30;
1807 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1808 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1809 		}
1810 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
1811 					u.ap);
1812 		chanctx_conf = rcu_dereference(ap_sdata->vif.chanctx_conf);
1813 		if (!chanctx_conf)
1814 			goto fail_rcu;
1815 		band = chanctx_conf->def.chan->band;
1816 		if (sta)
1817 			break;
1818 		/* fall through */
1819 	case NL80211_IFTYPE_AP:
1820 		if (sdata->vif.type == NL80211_IFTYPE_AP)
1821 			chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1822 		if (!chanctx_conf)
1823 			goto fail_rcu;
1824 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1825 		/* DA BSSID SA */
1826 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1827 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1828 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1829 		hdrlen = 24;
1830 		band = chanctx_conf->def.chan->band;
1831 		break;
1832 	case NL80211_IFTYPE_WDS:
1833 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1834 		/* RA TA DA SA */
1835 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1836 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1837 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
1838 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1839 		hdrlen = 30;
1840 		/*
1841 		 * This is the exception! WDS style interfaces are prohibited
1842 		 * when channel contexts are in used so this must be valid
1843 		 */
1844 		band = local->hw.conf.chandef.chan->band;
1845 		break;
1846 #ifdef CONFIG_MAC80211_MESH
1847 	case NL80211_IFTYPE_MESH_POINT:
1848 		if (!is_multicast_ether_addr(skb->data)) {
1849 			struct sta_info *next_hop;
1850 			bool mpp_lookup = true;
1851 
1852 			mpath = mesh_path_lookup(sdata, skb->data);
1853 			if (mpath) {
1854 				mpp_lookup = false;
1855 				next_hop = rcu_dereference(mpath->next_hop);
1856 				if (!next_hop ||
1857 				    !(mpath->flags & (MESH_PATH_ACTIVE |
1858 						      MESH_PATH_RESOLVING)))
1859 					mpp_lookup = true;
1860 			}
1861 
1862 			if (mpp_lookup)
1863 				mppath = mpp_path_lookup(sdata, skb->data);
1864 
1865 			if (mppath && mpath)
1866 				mesh_path_del(mpath->sdata, mpath->dst);
1867 		}
1868 
1869 		/*
1870 		 * Use address extension if it is a packet from
1871 		 * another interface or if we know the destination
1872 		 * is being proxied by a portal (i.e. portal address
1873 		 * differs from proxied address)
1874 		 */
1875 		if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
1876 		    !(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
1877 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1878 					skb->data, skb->data + ETH_ALEN);
1879 			meshhdrlen = ieee80211_new_mesh_header(sdata, &mesh_hdr,
1880 							       NULL, NULL);
1881 		} else {
1882 			/* DS -> MBSS (802.11-2012 13.11.3.3).
1883 			 * For unicast with unknown forwarding information,
1884 			 * destination might be in the MBSS or if that fails
1885 			 * forwarded to another mesh gate. In either case
1886 			 * resolution will be handled in ieee80211_xmit(), so
1887 			 * leave the original DA. This also works for mcast */
1888 			const u8 *mesh_da = skb->data;
1889 
1890 			if (mppath)
1891 				mesh_da = mppath->mpp;
1892 			else if (mpath)
1893 				mesh_da = mpath->dst;
1894 
1895 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1896 					mesh_da, sdata->vif.addr);
1897 			if (is_multicast_ether_addr(mesh_da))
1898 				/* DA TA mSA AE:SA */
1899 				meshhdrlen = ieee80211_new_mesh_header(
1900 						sdata, &mesh_hdr,
1901 						skb->data + ETH_ALEN, NULL);
1902 			else
1903 				/* RA TA mDA mSA AE:DA SA */
1904 				meshhdrlen = ieee80211_new_mesh_header(
1905 						sdata, &mesh_hdr, skb->data,
1906 						skb->data + ETH_ALEN);
1907 
1908 		}
1909 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1910 		if (!chanctx_conf)
1911 			goto fail_rcu;
1912 		band = chanctx_conf->def.chan->band;
1913 		break;
1914 #endif
1915 	case NL80211_IFTYPE_STATION:
1916 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
1917 			bool tdls_peer = false;
1918 
1919 			sta = sta_info_get(sdata, skb->data);
1920 			if (sta) {
1921 				authorized = test_sta_flag(sta,
1922 							WLAN_STA_AUTHORIZED);
1923 				wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1924 				tdls_peer = test_sta_flag(sta,
1925 							 WLAN_STA_TDLS_PEER);
1926 				tdls_auth = test_sta_flag(sta,
1927 						WLAN_STA_TDLS_PEER_AUTH);
1928 			}
1929 
1930 			/*
1931 			 * If the TDLS link is enabled, send everything
1932 			 * directly. Otherwise, allow TDLS setup frames
1933 			 * to be transmitted indirectly.
1934 			 */
1935 			tdls_direct = tdls_peer && (tdls_auth ||
1936 				 !(ethertype == ETH_P_TDLS && skb->len > 14 &&
1937 				   skb->data[14] == WLAN_TDLS_SNAP_RFTYPE));
1938 		}
1939 
1940 		if (tdls_direct) {
1941 			/* link during setup - throw out frames to peer */
1942 			if (!tdls_auth)
1943 				goto fail_rcu;
1944 
1945 			/* DA SA BSSID */
1946 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
1947 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1948 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
1949 			hdrlen = 24;
1950 		}  else if (sdata->u.mgd.use_4addr &&
1951 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
1952 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
1953 					  IEEE80211_FCTL_TODS);
1954 			/* RA TA DA SA */
1955 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1956 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1957 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1958 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1959 			hdrlen = 30;
1960 		} else {
1961 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1962 			/* BSSID SA DA */
1963 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1964 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1965 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1966 			hdrlen = 24;
1967 		}
1968 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1969 		if (!chanctx_conf)
1970 			goto fail_rcu;
1971 		band = chanctx_conf->def.chan->band;
1972 		break;
1973 	case NL80211_IFTYPE_ADHOC:
1974 		/* DA SA BSSID */
1975 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1976 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1977 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1978 		hdrlen = 24;
1979 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1980 		if (!chanctx_conf)
1981 			goto fail_rcu;
1982 		band = chanctx_conf->def.chan->band;
1983 		break;
1984 	default:
1985 		goto fail_rcu;
1986 	}
1987 
1988 	/*
1989 	 * There's no need to try to look up the destination
1990 	 * if it is a multicast address (which can only happen
1991 	 * in AP mode)
1992 	 */
1993 	multicast = is_multicast_ether_addr(hdr.addr1);
1994 	if (!multicast) {
1995 		sta = sta_info_get(sdata, hdr.addr1);
1996 		if (sta) {
1997 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1998 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1999 		}
2000 	}
2001 
2002 	/* For mesh, the use of the QoS header is mandatory */
2003 	if (ieee80211_vif_is_mesh(&sdata->vif))
2004 		wme_sta = true;
2005 
2006 	/* receiver and we are QoS enabled, use a QoS type frame */
2007 	if (wme_sta && local->hw.queues >= IEEE80211_NUM_ACS) {
2008 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2009 		hdrlen += 2;
2010 	}
2011 
2012 	/*
2013 	 * Drop unicast frames to unauthorised stations unless they are
2014 	 * EAPOL frames from the local station.
2015 	 */
2016 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
2017 		     !multicast && !authorized &&
2018 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
2019 		      !ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
2020 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
2021 		net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
2022 				    dev->name, hdr.addr1);
2023 #endif
2024 
2025 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
2026 
2027 		goto fail_rcu;
2028 	}
2029 
2030 	if (unlikely(!multicast && skb->sk &&
2031 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
2032 		struct sk_buff *orig_skb = skb;
2033 
2034 		skb = skb_clone(skb, GFP_ATOMIC);
2035 		if (skb) {
2036 			unsigned long flags;
2037 			int id;
2038 
2039 			spin_lock_irqsave(&local->ack_status_lock, flags);
2040 			id = idr_alloc(&local->ack_status_frames, orig_skb,
2041 				       1, 0x10000, GFP_ATOMIC);
2042 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
2043 
2044 			if (id >= 0) {
2045 				info_id = id;
2046 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
2047 			} else if (skb_shared(skb)) {
2048 				kfree_skb(orig_skb);
2049 			} else {
2050 				kfree_skb(skb);
2051 				skb = orig_skb;
2052 			}
2053 		} else {
2054 			/* couldn't clone -- lose tx status ... */
2055 			skb = orig_skb;
2056 		}
2057 	}
2058 
2059 	/*
2060 	 * If the skb is shared we need to obtain our own copy.
2061 	 */
2062 	if (skb_shared(skb)) {
2063 		struct sk_buff *tmp_skb = skb;
2064 
2065 		/* can't happen -- skb is a clone if info_id != 0 */
2066 		WARN_ON(info_id);
2067 
2068 		skb = skb_clone(skb, GFP_ATOMIC);
2069 		kfree_skb(tmp_skb);
2070 
2071 		if (!skb)
2072 			goto fail_rcu;
2073 	}
2074 
2075 	hdr.frame_control = fc;
2076 	hdr.duration_id = 0;
2077 	hdr.seq_ctrl = 0;
2078 
2079 	skip_header_bytes = ETH_HLEN;
2080 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2081 		encaps_data = bridge_tunnel_header;
2082 		encaps_len = sizeof(bridge_tunnel_header);
2083 		skip_header_bytes -= 2;
2084 	} else if (ethertype >= ETH_P_802_3_MIN) {
2085 		encaps_data = rfc1042_header;
2086 		encaps_len = sizeof(rfc1042_header);
2087 		skip_header_bytes -= 2;
2088 	} else {
2089 		encaps_data = NULL;
2090 		encaps_len = 0;
2091 	}
2092 
2093 	nh_pos = skb_network_header(skb) - skb->data;
2094 	h_pos = skb_transport_header(skb) - skb->data;
2095 
2096 	skb_pull(skb, skip_header_bytes);
2097 	nh_pos -= skip_header_bytes;
2098 	h_pos -= skip_header_bytes;
2099 
2100 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2101 
2102 	/*
2103 	 * So we need to modify the skb header and hence need a copy of
2104 	 * that. The head_need variable above doesn't, so far, include
2105 	 * the needed header space that we don't need right away. If we
2106 	 * can, then we don't reallocate right now but only after the
2107 	 * frame arrives at the master device (if it does...)
2108 	 *
2109 	 * If we cannot, however, then we will reallocate to include all
2110 	 * the ever needed space. Also, if we need to reallocate it anyway,
2111 	 * make it big enough for everything we may ever need.
2112 	 */
2113 
2114 	if (head_need > 0 || skb_cloned(skb)) {
2115 		head_need += IEEE80211_ENCRYPT_HEADROOM;
2116 		head_need += local->tx_headroom;
2117 		head_need = max_t(int, 0, head_need);
2118 		if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
2119 			ieee80211_free_txskb(&local->hw, skb);
2120 			skb = NULL;
2121 			goto fail_rcu;
2122 		}
2123 	}
2124 
2125 	if (encaps_data) {
2126 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2127 		nh_pos += encaps_len;
2128 		h_pos += encaps_len;
2129 	}
2130 
2131 #ifdef CONFIG_MAC80211_MESH
2132 	if (meshhdrlen > 0) {
2133 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2134 		nh_pos += meshhdrlen;
2135 		h_pos += meshhdrlen;
2136 	}
2137 #endif
2138 
2139 	if (ieee80211_is_data_qos(fc)) {
2140 		__le16 *qos_control;
2141 
2142 		qos_control = (__le16*) skb_push(skb, 2);
2143 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2144 		/*
2145 		 * Maybe we could actually set some fields here, for now just
2146 		 * initialise to zero to indicate no special operation.
2147 		 */
2148 		*qos_control = 0;
2149 	} else
2150 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2151 
2152 	nh_pos += hdrlen;
2153 	h_pos += hdrlen;
2154 
2155 	dev->stats.tx_packets++;
2156 	dev->stats.tx_bytes += skb->len;
2157 
2158 	/* Update skb pointers to various headers since this modified frame
2159 	 * is going to go through Linux networking code that may potentially
2160 	 * need things like pointer to IP header. */
2161 	skb_set_mac_header(skb, 0);
2162 	skb_set_network_header(skb, nh_pos);
2163 	skb_set_transport_header(skb, h_pos);
2164 
2165 	info = IEEE80211_SKB_CB(skb);
2166 	memset(info, 0, sizeof(*info));
2167 
2168 	dev->trans_start = jiffies;
2169 
2170 	info->flags = info_flags;
2171 	info->ack_frame_id = info_id;
2172 
2173 	ieee80211_xmit(sdata, skb, band);
2174 	rcu_read_unlock();
2175 
2176 	return NETDEV_TX_OK;
2177 
2178  fail_rcu:
2179 	rcu_read_unlock();
2180  fail:
2181 	dev_kfree_skb(skb);
2182 	return NETDEV_TX_OK;
2183 }
2184 
2185 
2186 /*
2187  * ieee80211_clear_tx_pending may not be called in a context where
2188  * it is possible that it packets could come in again.
2189  */
2190 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2191 {
2192 	struct sk_buff *skb;
2193 	int i;
2194 
2195 	for (i = 0; i < local->hw.queues; i++) {
2196 		while ((skb = skb_dequeue(&local->pending[i])) != NULL)
2197 			ieee80211_free_txskb(&local->hw, skb);
2198 	}
2199 }
2200 
2201 /*
2202  * Returns false if the frame couldn't be transmitted but was queued instead,
2203  * which in this case means re-queued -- take as an indication to stop sending
2204  * more pending frames.
2205  */
2206 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2207 				     struct sk_buff *skb)
2208 {
2209 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2210 	struct ieee80211_sub_if_data *sdata;
2211 	struct sta_info *sta;
2212 	struct ieee80211_hdr *hdr;
2213 	bool result;
2214 	struct ieee80211_chanctx_conf *chanctx_conf;
2215 
2216 	sdata = vif_to_sdata(info->control.vif);
2217 
2218 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
2219 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2220 		if (unlikely(!chanctx_conf)) {
2221 			dev_kfree_skb(skb);
2222 			return true;
2223 		}
2224 		result = ieee80211_tx(sdata, skb, true,
2225 				      chanctx_conf->def.chan->band);
2226 	} else {
2227 		struct sk_buff_head skbs;
2228 
2229 		__skb_queue_head_init(&skbs);
2230 		__skb_queue_tail(&skbs, skb);
2231 
2232 		hdr = (struct ieee80211_hdr *)skb->data;
2233 		sta = sta_info_get(sdata, hdr->addr1);
2234 
2235 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
2236 	}
2237 
2238 	return result;
2239 }
2240 
2241 /*
2242  * Transmit all pending packets. Called from tasklet.
2243  */
2244 void ieee80211_tx_pending(unsigned long data)
2245 {
2246 	struct ieee80211_local *local = (struct ieee80211_local *)data;
2247 	unsigned long flags;
2248 	int i;
2249 	bool txok;
2250 
2251 	rcu_read_lock();
2252 
2253 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
2254 	for (i = 0; i < local->hw.queues; i++) {
2255 		/*
2256 		 * If queue is stopped by something other than due to pending
2257 		 * frames, or we have no pending frames, proceed to next queue.
2258 		 */
2259 		if (local->queue_stop_reasons[i] ||
2260 		    skb_queue_empty(&local->pending[i]))
2261 			continue;
2262 
2263 		while (!skb_queue_empty(&local->pending[i])) {
2264 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
2265 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2266 
2267 			if (WARN_ON(!info->control.vif)) {
2268 				ieee80211_free_txskb(&local->hw, skb);
2269 				continue;
2270 			}
2271 
2272 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
2273 						flags);
2274 
2275 			txok = ieee80211_tx_pending_skb(local, skb);
2276 			spin_lock_irqsave(&local->queue_stop_reason_lock,
2277 					  flags);
2278 			if (!txok)
2279 				break;
2280 		}
2281 
2282 		if (skb_queue_empty(&local->pending[i]))
2283 			ieee80211_propagate_queue_wake(local, i);
2284 	}
2285 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
2286 
2287 	rcu_read_unlock();
2288 }
2289 
2290 /* functions for drivers to get certain frames */
2291 
2292 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2293 				       struct ps_data *ps, struct sk_buff *skb)
2294 {
2295 	u8 *pos, *tim;
2296 	int aid0 = 0;
2297 	int i, have_bits = 0, n1, n2;
2298 
2299 	/* Generate bitmap for TIM only if there are any STAs in power save
2300 	 * mode. */
2301 	if (atomic_read(&ps->num_sta_ps) > 0)
2302 		/* in the hope that this is faster than
2303 		 * checking byte-for-byte */
2304 		have_bits = !bitmap_empty((unsigned long*)ps->tim,
2305 					  IEEE80211_MAX_AID+1);
2306 
2307 	if (ps->dtim_count == 0)
2308 		ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
2309 	else
2310 		ps->dtim_count--;
2311 
2312 	tim = pos = (u8 *) skb_put(skb, 6);
2313 	*pos++ = WLAN_EID_TIM;
2314 	*pos++ = 4;
2315 	*pos++ = ps->dtim_count;
2316 	*pos++ = sdata->vif.bss_conf.dtim_period;
2317 
2318 	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
2319 		aid0 = 1;
2320 
2321 	ps->dtim_bc_mc = aid0 == 1;
2322 
2323 	if (have_bits) {
2324 		/* Find largest even number N1 so that bits numbered 1 through
2325 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2326 		 * (N2 + 1) x 8 through 2007 are 0. */
2327 		n1 = 0;
2328 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2329 			if (ps->tim[i]) {
2330 				n1 = i & 0xfe;
2331 				break;
2332 			}
2333 		}
2334 		n2 = n1;
2335 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2336 			if (ps->tim[i]) {
2337 				n2 = i;
2338 				break;
2339 			}
2340 		}
2341 
2342 		/* Bitmap control */
2343 		*pos++ = n1 | aid0;
2344 		/* Part Virt Bitmap */
2345 		skb_put(skb, n2 - n1);
2346 		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
2347 
2348 		tim[1] = n2 - n1 + 4;
2349 	} else {
2350 		*pos++ = aid0; /* Bitmap control */
2351 		*pos++ = 0; /* Part Virt Bitmap */
2352 	}
2353 }
2354 
2355 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2356 				    struct ps_data *ps, struct sk_buff *skb)
2357 {
2358 	struct ieee80211_local *local = sdata->local;
2359 
2360 	/*
2361 	 * Not very nice, but we want to allow the driver to call
2362 	 * ieee80211_beacon_get() as a response to the set_tim()
2363 	 * callback. That, however, is already invoked under the
2364 	 * sta_lock to guarantee consistent and race-free update
2365 	 * of the tim bitmap in mac80211 and the driver.
2366 	 */
2367 	if (local->tim_in_locked_section) {
2368 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2369 	} else {
2370 		spin_lock_bh(&local->tim_lock);
2371 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2372 		spin_unlock_bh(&local->tim_lock);
2373 	}
2374 
2375 	return 0;
2376 }
2377 
2378 void ieee80211_csa_finish(struct ieee80211_vif *vif)
2379 {
2380 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2381 
2382 	ieee80211_queue_work(&sdata->local->hw,
2383 			     &sdata->csa_finalize_work);
2384 }
2385 EXPORT_SYMBOL(ieee80211_csa_finish);
2386 
2387 static void ieee80211_update_csa(struct ieee80211_sub_if_data *sdata,
2388 				 struct beacon_data *beacon)
2389 {
2390 	struct probe_resp *resp;
2391 	int counter_offset_beacon = sdata->csa_counter_offset_beacon;
2392 	int counter_offset_presp = sdata->csa_counter_offset_presp;
2393 	u8 *beacon_data;
2394 	size_t beacon_data_len;
2395 
2396 	switch (sdata->vif.type) {
2397 	case NL80211_IFTYPE_AP:
2398 		beacon_data = beacon->tail;
2399 		beacon_data_len = beacon->tail_len;
2400 		break;
2401 	case NL80211_IFTYPE_ADHOC:
2402 		beacon_data = beacon->head;
2403 		beacon_data_len = beacon->head_len;
2404 		break;
2405 	case NL80211_IFTYPE_MESH_POINT:
2406 		beacon_data = beacon->head;
2407 		beacon_data_len = beacon->head_len;
2408 		break;
2409 	default:
2410 		return;
2411 	}
2412 	if (WARN_ON(counter_offset_beacon >= beacon_data_len))
2413 		return;
2414 
2415 	/* warn if the driver did not check for/react to csa completeness */
2416 	if (WARN_ON(beacon_data[counter_offset_beacon] == 0))
2417 		return;
2418 
2419 	beacon_data[counter_offset_beacon]--;
2420 
2421 	if (sdata->vif.type == NL80211_IFTYPE_AP && counter_offset_presp) {
2422 		rcu_read_lock();
2423 		resp = rcu_dereference(sdata->u.ap.probe_resp);
2424 
2425 		/* if nl80211 accepted the offset, this should not happen. */
2426 		if (WARN_ON(!resp)) {
2427 			rcu_read_unlock();
2428 			return;
2429 		}
2430 		resp->data[counter_offset_presp]--;
2431 		rcu_read_unlock();
2432 	}
2433 }
2434 
2435 bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
2436 {
2437 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2438 	struct beacon_data *beacon = NULL;
2439 	u8 *beacon_data;
2440 	size_t beacon_data_len;
2441 	int counter_beacon = sdata->csa_counter_offset_beacon;
2442 	int ret = false;
2443 
2444 	if (!ieee80211_sdata_running(sdata))
2445 		return false;
2446 
2447 	rcu_read_lock();
2448 	if (vif->type == NL80211_IFTYPE_AP) {
2449 		struct ieee80211_if_ap *ap = &sdata->u.ap;
2450 
2451 		beacon = rcu_dereference(ap->beacon);
2452 		if (WARN_ON(!beacon || !beacon->tail))
2453 			goto out;
2454 		beacon_data = beacon->tail;
2455 		beacon_data_len = beacon->tail_len;
2456 	} else if (vif->type == NL80211_IFTYPE_ADHOC) {
2457 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2458 
2459 		beacon = rcu_dereference(ifibss->presp);
2460 		if (!beacon)
2461 			goto out;
2462 
2463 		beacon_data = beacon->head;
2464 		beacon_data_len = beacon->head_len;
2465 	} else if (vif->type == NL80211_IFTYPE_MESH_POINT) {
2466 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2467 
2468 		beacon = rcu_dereference(ifmsh->beacon);
2469 		if (!beacon)
2470 			goto out;
2471 
2472 		beacon_data = beacon->head;
2473 		beacon_data_len = beacon->head_len;
2474 	} else {
2475 		WARN_ON(1);
2476 		goto out;
2477 	}
2478 
2479 	if (WARN_ON(counter_beacon > beacon_data_len))
2480 		goto out;
2481 
2482 	if (beacon_data[counter_beacon] == 0)
2483 		ret = true;
2484  out:
2485 	rcu_read_unlock();
2486 
2487 	return ret;
2488 }
2489 EXPORT_SYMBOL(ieee80211_csa_is_complete);
2490 
2491 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2492 					 struct ieee80211_vif *vif,
2493 					 u16 *tim_offset, u16 *tim_length)
2494 {
2495 	struct ieee80211_local *local = hw_to_local(hw);
2496 	struct sk_buff *skb = NULL;
2497 	struct ieee80211_tx_info *info;
2498 	struct ieee80211_sub_if_data *sdata = NULL;
2499 	enum ieee80211_band band;
2500 	struct ieee80211_tx_rate_control txrc;
2501 	struct ieee80211_chanctx_conf *chanctx_conf;
2502 
2503 	rcu_read_lock();
2504 
2505 	sdata = vif_to_sdata(vif);
2506 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2507 
2508 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
2509 		goto out;
2510 
2511 	if (tim_offset)
2512 		*tim_offset = 0;
2513 	if (tim_length)
2514 		*tim_length = 0;
2515 
2516 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2517 		struct ieee80211_if_ap *ap = &sdata->u.ap;
2518 		struct beacon_data *beacon = rcu_dereference(ap->beacon);
2519 
2520 		if (beacon) {
2521 			if (sdata->vif.csa_active)
2522 				ieee80211_update_csa(sdata, beacon);
2523 
2524 			/*
2525 			 * headroom, head length,
2526 			 * tail length and maximum TIM length
2527 			 */
2528 			skb = dev_alloc_skb(local->tx_headroom +
2529 					    beacon->head_len +
2530 					    beacon->tail_len + 256);
2531 			if (!skb)
2532 				goto out;
2533 
2534 			skb_reserve(skb, local->tx_headroom);
2535 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
2536 			       beacon->head_len);
2537 
2538 			ieee80211_beacon_add_tim(sdata, &ap->ps, skb);
2539 
2540 			if (tim_offset)
2541 				*tim_offset = beacon->head_len;
2542 			if (tim_length)
2543 				*tim_length = skb->len - beacon->head_len;
2544 
2545 			if (beacon->tail)
2546 				memcpy(skb_put(skb, beacon->tail_len),
2547 				       beacon->tail, beacon->tail_len);
2548 		} else
2549 			goto out;
2550 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2551 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2552 		struct ieee80211_hdr *hdr;
2553 		struct beacon_data *presp = rcu_dereference(ifibss->presp);
2554 
2555 		if (!presp)
2556 			goto out;
2557 
2558 		if (sdata->vif.csa_active)
2559 			ieee80211_update_csa(sdata, presp);
2560 
2561 
2562 		skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
2563 		if (!skb)
2564 			goto out;
2565 		skb_reserve(skb, local->tx_headroom);
2566 		memcpy(skb_put(skb, presp->head_len), presp->head,
2567 		       presp->head_len);
2568 
2569 		hdr = (struct ieee80211_hdr *) skb->data;
2570 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2571 						 IEEE80211_STYPE_BEACON);
2572 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2573 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2574 		struct beacon_data *bcn = rcu_dereference(ifmsh->beacon);
2575 
2576 		if (!bcn)
2577 			goto out;
2578 
2579 		if (sdata->vif.csa_active)
2580 			ieee80211_update_csa(sdata, bcn);
2581 
2582 		if (ifmsh->sync_ops)
2583 			ifmsh->sync_ops->adjust_tbtt(
2584 						sdata);
2585 
2586 		skb = dev_alloc_skb(local->tx_headroom +
2587 				    bcn->head_len +
2588 				    256 + /* TIM IE */
2589 				    bcn->tail_len);
2590 		if (!skb)
2591 			goto out;
2592 		skb_reserve(skb, local->tx_headroom);
2593 		memcpy(skb_put(skb, bcn->head_len), bcn->head, bcn->head_len);
2594 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb);
2595 		memcpy(skb_put(skb, bcn->tail_len), bcn->tail, bcn->tail_len);
2596 	} else {
2597 		WARN_ON(1);
2598 		goto out;
2599 	}
2600 
2601 	band = chanctx_conf->def.chan->band;
2602 
2603 	info = IEEE80211_SKB_CB(skb);
2604 
2605 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2606 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
2607 	info->band = band;
2608 
2609 	memset(&txrc, 0, sizeof(txrc));
2610 	txrc.hw = hw;
2611 	txrc.sband = local->hw.wiphy->bands[band];
2612 	txrc.bss_conf = &sdata->vif.bss_conf;
2613 	txrc.skb = skb;
2614 	txrc.reported_rate.idx = -1;
2615 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
2616 	if (txrc.rate_idx_mask == (1 << txrc.sband->n_bitrates) - 1)
2617 		txrc.max_rate_idx = -1;
2618 	else
2619 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
2620 	txrc.bss = true;
2621 	rate_control_get_rate(sdata, NULL, &txrc);
2622 
2623 	info->control.vif = vif;
2624 
2625 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
2626 			IEEE80211_TX_CTL_ASSIGN_SEQ |
2627 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
2628  out:
2629 	rcu_read_unlock();
2630 	return skb;
2631 }
2632 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
2633 
2634 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
2635 					struct ieee80211_vif *vif)
2636 {
2637 	struct ieee80211_if_ap *ap = NULL;
2638 	struct sk_buff *skb = NULL;
2639 	struct probe_resp *presp = NULL;
2640 	struct ieee80211_hdr *hdr;
2641 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2642 
2643 	if (sdata->vif.type != NL80211_IFTYPE_AP)
2644 		return NULL;
2645 
2646 	rcu_read_lock();
2647 
2648 	ap = &sdata->u.ap;
2649 	presp = rcu_dereference(ap->probe_resp);
2650 	if (!presp)
2651 		goto out;
2652 
2653 	skb = dev_alloc_skb(presp->len);
2654 	if (!skb)
2655 		goto out;
2656 
2657 	memcpy(skb_put(skb, presp->len), presp->data, presp->len);
2658 
2659 	hdr = (struct ieee80211_hdr *) skb->data;
2660 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
2661 
2662 out:
2663 	rcu_read_unlock();
2664 	return skb;
2665 }
2666 EXPORT_SYMBOL(ieee80211_proberesp_get);
2667 
2668 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
2669 				     struct ieee80211_vif *vif)
2670 {
2671 	struct ieee80211_sub_if_data *sdata;
2672 	struct ieee80211_if_managed *ifmgd;
2673 	struct ieee80211_pspoll *pspoll;
2674 	struct ieee80211_local *local;
2675 	struct sk_buff *skb;
2676 
2677 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2678 		return NULL;
2679 
2680 	sdata = vif_to_sdata(vif);
2681 	ifmgd = &sdata->u.mgd;
2682 	local = sdata->local;
2683 
2684 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
2685 	if (!skb)
2686 		return NULL;
2687 
2688 	skb_reserve(skb, local->hw.extra_tx_headroom);
2689 
2690 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
2691 	memset(pspoll, 0, sizeof(*pspoll));
2692 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
2693 					    IEEE80211_STYPE_PSPOLL);
2694 	pspoll->aid = cpu_to_le16(ifmgd->aid);
2695 
2696 	/* aid in PS-Poll has its two MSBs each set to 1 */
2697 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
2698 
2699 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
2700 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
2701 
2702 	return skb;
2703 }
2704 EXPORT_SYMBOL(ieee80211_pspoll_get);
2705 
2706 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
2707 				       struct ieee80211_vif *vif)
2708 {
2709 	struct ieee80211_hdr_3addr *nullfunc;
2710 	struct ieee80211_sub_if_data *sdata;
2711 	struct ieee80211_if_managed *ifmgd;
2712 	struct ieee80211_local *local;
2713 	struct sk_buff *skb;
2714 
2715 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2716 		return NULL;
2717 
2718 	sdata = vif_to_sdata(vif);
2719 	ifmgd = &sdata->u.mgd;
2720 	local = sdata->local;
2721 
2722 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
2723 	if (!skb)
2724 		return NULL;
2725 
2726 	skb_reserve(skb, local->hw.extra_tx_headroom);
2727 
2728 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
2729 							  sizeof(*nullfunc));
2730 	memset(nullfunc, 0, sizeof(*nullfunc));
2731 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
2732 					      IEEE80211_STYPE_NULLFUNC |
2733 					      IEEE80211_FCTL_TODS);
2734 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
2735 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
2736 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
2737 
2738 	return skb;
2739 }
2740 EXPORT_SYMBOL(ieee80211_nullfunc_get);
2741 
2742 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
2743 				       struct ieee80211_vif *vif,
2744 				       const u8 *ssid, size_t ssid_len,
2745 				       size_t tailroom)
2746 {
2747 	struct ieee80211_sub_if_data *sdata;
2748 	struct ieee80211_local *local;
2749 	struct ieee80211_hdr_3addr *hdr;
2750 	struct sk_buff *skb;
2751 	size_t ie_ssid_len;
2752 	u8 *pos;
2753 
2754 	sdata = vif_to_sdata(vif);
2755 	local = sdata->local;
2756 	ie_ssid_len = 2 + ssid_len;
2757 
2758 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
2759 			    ie_ssid_len + tailroom);
2760 	if (!skb)
2761 		return NULL;
2762 
2763 	skb_reserve(skb, local->hw.extra_tx_headroom);
2764 
2765 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
2766 	memset(hdr, 0, sizeof(*hdr));
2767 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2768 					 IEEE80211_STYPE_PROBE_REQ);
2769 	eth_broadcast_addr(hdr->addr1);
2770 	memcpy(hdr->addr2, vif->addr, ETH_ALEN);
2771 	eth_broadcast_addr(hdr->addr3);
2772 
2773 	pos = skb_put(skb, ie_ssid_len);
2774 	*pos++ = WLAN_EID_SSID;
2775 	*pos++ = ssid_len;
2776 	if (ssid_len)
2777 		memcpy(pos, ssid, ssid_len);
2778 	pos += ssid_len;
2779 
2780 	return skb;
2781 }
2782 EXPORT_SYMBOL(ieee80211_probereq_get);
2783 
2784 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2785 		       const void *frame, size_t frame_len,
2786 		       const struct ieee80211_tx_info *frame_txctl,
2787 		       struct ieee80211_rts *rts)
2788 {
2789 	const struct ieee80211_hdr *hdr = frame;
2790 
2791 	rts->frame_control =
2792 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2793 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2794 					       frame_txctl);
2795 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2796 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2797 }
2798 EXPORT_SYMBOL(ieee80211_rts_get);
2799 
2800 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2801 			     const void *frame, size_t frame_len,
2802 			     const struct ieee80211_tx_info *frame_txctl,
2803 			     struct ieee80211_cts *cts)
2804 {
2805 	const struct ieee80211_hdr *hdr = frame;
2806 
2807 	cts->frame_control =
2808 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2809 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
2810 						     frame_len, frame_txctl);
2811 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2812 }
2813 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2814 
2815 struct sk_buff *
2816 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2817 			  struct ieee80211_vif *vif)
2818 {
2819 	struct ieee80211_local *local = hw_to_local(hw);
2820 	struct sk_buff *skb = NULL;
2821 	struct ieee80211_tx_data tx;
2822 	struct ieee80211_sub_if_data *sdata;
2823 	struct ps_data *ps;
2824 	struct ieee80211_tx_info *info;
2825 	struct ieee80211_chanctx_conf *chanctx_conf;
2826 
2827 	sdata = vif_to_sdata(vif);
2828 
2829 	rcu_read_lock();
2830 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2831 
2832 	if (!chanctx_conf)
2833 		goto out;
2834 
2835 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2836 		struct beacon_data *beacon =
2837 				rcu_dereference(sdata->u.ap.beacon);
2838 
2839 		if (!beacon || !beacon->head)
2840 			goto out;
2841 
2842 		ps = &sdata->u.ap.ps;
2843 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2844 		ps = &sdata->u.mesh.ps;
2845 	} else {
2846 		goto out;
2847 	}
2848 
2849 	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
2850 		goto out; /* send buffered bc/mc only after DTIM beacon */
2851 
2852 	while (1) {
2853 		skb = skb_dequeue(&ps->bc_buf);
2854 		if (!skb)
2855 			goto out;
2856 		local->total_ps_buffered--;
2857 
2858 		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
2859 			struct ieee80211_hdr *hdr =
2860 				(struct ieee80211_hdr *) skb->data;
2861 			/* more buffered multicast/broadcast frames ==> set
2862 			 * MoreData flag in IEEE 802.11 header to inform PS
2863 			 * STAs */
2864 			hdr->frame_control |=
2865 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2866 		}
2867 
2868 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2869 			sdata = IEEE80211_DEV_TO_SUB_IF(skb->dev);
2870 		if (!ieee80211_tx_prepare(sdata, &tx, skb))
2871 			break;
2872 		dev_kfree_skb_any(skb);
2873 	}
2874 
2875 	info = IEEE80211_SKB_CB(skb);
2876 
2877 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
2878 	info->band = chanctx_conf->def.chan->band;
2879 
2880 	if (invoke_tx_handlers(&tx))
2881 		skb = NULL;
2882  out:
2883 	rcu_read_unlock();
2884 
2885 	return skb;
2886 }
2887 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2888 
2889 void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
2890 				 struct sk_buff *skb, int tid,
2891 				 enum ieee80211_band band)
2892 {
2893 	int ac = ieee802_1d_to_ac[tid & 7];
2894 
2895 	skb_set_mac_header(skb, 0);
2896 	skb_set_network_header(skb, 0);
2897 	skb_set_transport_header(skb, 0);
2898 
2899 	skb_set_queue_mapping(skb, ac);
2900 	skb->priority = tid;
2901 
2902 	skb->dev = sdata->dev;
2903 
2904 	/*
2905 	 * The other path calling ieee80211_xmit is from the tasklet,
2906 	 * and while we can handle concurrent transmissions locking
2907 	 * requirements are that we do not come into tx with bhs on.
2908 	 */
2909 	local_bh_disable();
2910 	ieee80211_xmit(sdata, skb, band);
2911 	local_bh_enable();
2912 }
2913