xref: /linux/net/mac80211/tx.c (revision 9ee0034b8f49aaaa7e7c2da8db1038915db99c19)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  *
13  * Transmit and frame generation functions.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/skbuff.h>
19 #include <linux/etherdevice.h>
20 #include <linux/bitmap.h>
21 #include <linux/rcupdate.h>
22 #include <linux/export.h>
23 #include <net/net_namespace.h>
24 #include <net/ieee80211_radiotap.h>
25 #include <net/cfg80211.h>
26 #include <net/mac80211.h>
27 #include <net/codel.h>
28 #include <net/codel_impl.h>
29 #include <asm/unaligned.h>
30 #include <net/fq_impl.h>
31 
32 #include "ieee80211_i.h"
33 #include "driver-ops.h"
34 #include "led.h"
35 #include "mesh.h"
36 #include "wep.h"
37 #include "wpa.h"
38 #include "wme.h"
39 #include "rate.h"
40 
41 /* misc utils */
42 
43 static inline void ieee80211_tx_stats(struct net_device *dev, u32 len)
44 {
45 	struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
46 
47 	u64_stats_update_begin(&tstats->syncp);
48 	tstats->tx_packets++;
49 	tstats->tx_bytes += len;
50 	u64_stats_update_end(&tstats->syncp);
51 }
52 
53 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx,
54 				 struct sk_buff *skb, int group_addr,
55 				 int next_frag_len)
56 {
57 	int rate, mrate, erp, dur, i, shift = 0;
58 	struct ieee80211_rate *txrate;
59 	struct ieee80211_local *local = tx->local;
60 	struct ieee80211_supported_band *sband;
61 	struct ieee80211_hdr *hdr;
62 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
63 	struct ieee80211_chanctx_conf *chanctx_conf;
64 	u32 rate_flags = 0;
65 
66 	rcu_read_lock();
67 	chanctx_conf = rcu_dereference(tx->sdata->vif.chanctx_conf);
68 	if (chanctx_conf) {
69 		shift = ieee80211_chandef_get_shift(&chanctx_conf->def);
70 		rate_flags = ieee80211_chandef_rate_flags(&chanctx_conf->def);
71 	}
72 	rcu_read_unlock();
73 
74 	/* assume HW handles this */
75 	if (tx->rate.flags & (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))
76 		return 0;
77 
78 	/* uh huh? */
79 	if (WARN_ON_ONCE(tx->rate.idx < 0))
80 		return 0;
81 
82 	sband = local->hw.wiphy->bands[info->band];
83 	txrate = &sband->bitrates[tx->rate.idx];
84 
85 	erp = txrate->flags & IEEE80211_RATE_ERP_G;
86 
87 	/*
88 	 * data and mgmt (except PS Poll):
89 	 * - during CFP: 32768
90 	 * - during contention period:
91 	 *   if addr1 is group address: 0
92 	 *   if more fragments = 0 and addr1 is individual address: time to
93 	 *      transmit one ACK plus SIFS
94 	 *   if more fragments = 1 and addr1 is individual address: time to
95 	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
96 	 *
97 	 * IEEE 802.11, 9.6:
98 	 * - control response frame (CTS or ACK) shall be transmitted using the
99 	 *   same rate as the immediately previous frame in the frame exchange
100 	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
101 	 *   at the highest possible rate belonging to the PHY rates in the
102 	 *   BSSBasicRateSet
103 	 */
104 	hdr = (struct ieee80211_hdr *)skb->data;
105 	if (ieee80211_is_ctl(hdr->frame_control)) {
106 		/* TODO: These control frames are not currently sent by
107 		 * mac80211, but should they be implemented, this function
108 		 * needs to be updated to support duration field calculation.
109 		 *
110 		 * RTS: time needed to transmit pending data/mgmt frame plus
111 		 *    one CTS frame plus one ACK frame plus 3 x SIFS
112 		 * CTS: duration of immediately previous RTS minus time
113 		 *    required to transmit CTS and its SIFS
114 		 * ACK: 0 if immediately previous directed data/mgmt had
115 		 *    more=0, with more=1 duration in ACK frame is duration
116 		 *    from previous frame minus time needed to transmit ACK
117 		 *    and its SIFS
118 		 * PS Poll: BIT(15) | BIT(14) | aid
119 		 */
120 		return 0;
121 	}
122 
123 	/* data/mgmt */
124 	if (0 /* FIX: data/mgmt during CFP */)
125 		return cpu_to_le16(32768);
126 
127 	if (group_addr) /* Group address as the destination - no ACK */
128 		return 0;
129 
130 	/* Individual destination address:
131 	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
132 	 * CTS and ACK frames shall be transmitted using the highest rate in
133 	 * basic rate set that is less than or equal to the rate of the
134 	 * immediately previous frame and that is using the same modulation
135 	 * (CCK or OFDM). If no basic rate set matches with these requirements,
136 	 * the highest mandatory rate of the PHY that is less than or equal to
137 	 * the rate of the previous frame is used.
138 	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
139 	 */
140 	rate = -1;
141 	/* use lowest available if everything fails */
142 	mrate = sband->bitrates[0].bitrate;
143 	for (i = 0; i < sband->n_bitrates; i++) {
144 		struct ieee80211_rate *r = &sband->bitrates[i];
145 
146 		if (r->bitrate > txrate->bitrate)
147 			break;
148 
149 		if ((rate_flags & r->flags) != rate_flags)
150 			continue;
151 
152 		if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
153 			rate = DIV_ROUND_UP(r->bitrate, 1 << shift);
154 
155 		switch (sband->band) {
156 		case NL80211_BAND_2GHZ: {
157 			u32 flag;
158 			if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
159 				flag = IEEE80211_RATE_MANDATORY_G;
160 			else
161 				flag = IEEE80211_RATE_MANDATORY_B;
162 			if (r->flags & flag)
163 				mrate = r->bitrate;
164 			break;
165 		}
166 		case NL80211_BAND_5GHZ:
167 			if (r->flags & IEEE80211_RATE_MANDATORY_A)
168 				mrate = r->bitrate;
169 			break;
170 		case NL80211_BAND_60GHZ:
171 			/* TODO, for now fall through */
172 		case NUM_NL80211_BANDS:
173 			WARN_ON(1);
174 			break;
175 		}
176 	}
177 	if (rate == -1) {
178 		/* No matching basic rate found; use highest suitable mandatory
179 		 * PHY rate */
180 		rate = DIV_ROUND_UP(mrate, 1 << shift);
181 	}
182 
183 	/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
184 	if (ieee80211_is_data_qos(hdr->frame_control) &&
185 	    *(ieee80211_get_qos_ctl(hdr)) & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
186 		dur = 0;
187 	else
188 		/* Time needed to transmit ACK
189 		 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
190 		 * to closest integer */
191 		dur = ieee80211_frame_duration(sband->band, 10, rate, erp,
192 				tx->sdata->vif.bss_conf.use_short_preamble,
193 				shift);
194 
195 	if (next_frag_len) {
196 		/* Frame is fragmented: duration increases with time needed to
197 		 * transmit next fragment plus ACK and 2 x SIFS. */
198 		dur *= 2; /* ACK + SIFS */
199 		/* next fragment */
200 		dur += ieee80211_frame_duration(sband->band, next_frag_len,
201 				txrate->bitrate, erp,
202 				tx->sdata->vif.bss_conf.use_short_preamble,
203 				shift);
204 	}
205 
206 	return cpu_to_le16(dur);
207 }
208 
209 /* tx handlers */
210 static ieee80211_tx_result debug_noinline
211 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
212 {
213 	struct ieee80211_local *local = tx->local;
214 	struct ieee80211_if_managed *ifmgd;
215 
216 	/* driver doesn't support power save */
217 	if (!ieee80211_hw_check(&local->hw, SUPPORTS_PS))
218 		return TX_CONTINUE;
219 
220 	/* hardware does dynamic power save */
221 	if (ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
222 		return TX_CONTINUE;
223 
224 	/* dynamic power save disabled */
225 	if (local->hw.conf.dynamic_ps_timeout <= 0)
226 		return TX_CONTINUE;
227 
228 	/* we are scanning, don't enable power save */
229 	if (local->scanning)
230 		return TX_CONTINUE;
231 
232 	if (!local->ps_sdata)
233 		return TX_CONTINUE;
234 
235 	/* No point if we're going to suspend */
236 	if (local->quiescing)
237 		return TX_CONTINUE;
238 
239 	/* dynamic ps is supported only in managed mode */
240 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
241 		return TX_CONTINUE;
242 
243 	ifmgd = &tx->sdata->u.mgd;
244 
245 	/*
246 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
247 	 * u-apsd enabled and the frame is in voip class. This effectively
248 	 * means that even if all access categories have u-apsd enabled, in
249 	 * practise u-apsd is only used with the voip ac. This is a
250 	 * workaround for the case when received voip class packets do not
251 	 * have correct qos tag for some reason, due the network or the
252 	 * peer application.
253 	 *
254 	 * Note: ifmgd->uapsd_queues access is racy here. If the value is
255 	 * changed via debugfs, user needs to reassociate manually to have
256 	 * everything in sync.
257 	 */
258 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
259 	    (ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
260 	    skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
261 		return TX_CONTINUE;
262 
263 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
264 		ieee80211_stop_queues_by_reason(&local->hw,
265 						IEEE80211_MAX_QUEUE_MAP,
266 						IEEE80211_QUEUE_STOP_REASON_PS,
267 						false);
268 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
269 		ieee80211_queue_work(&local->hw,
270 				     &local->dynamic_ps_disable_work);
271 	}
272 
273 	/* Don't restart the timer if we're not disassociated */
274 	if (!ifmgd->associated)
275 		return TX_CONTINUE;
276 
277 	mod_timer(&local->dynamic_ps_timer, jiffies +
278 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
279 
280 	return TX_CONTINUE;
281 }
282 
283 static ieee80211_tx_result debug_noinline
284 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
285 {
286 
287 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
288 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
289 	bool assoc = false;
290 
291 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
292 		return TX_CONTINUE;
293 
294 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
295 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
296 	    !ieee80211_is_probe_req(hdr->frame_control) &&
297 	    !ieee80211_is_nullfunc(hdr->frame_control))
298 		/*
299 		 * When software scanning only nullfunc frames (to notify
300 		 * the sleep state to the AP) and probe requests (for the
301 		 * active scan) are allowed, all other frames should not be
302 		 * sent and we should not get here, but if we do
303 		 * nonetheless, drop them to avoid sending them
304 		 * off-channel. See the link below and
305 		 * ieee80211_start_scan() for more.
306 		 *
307 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
308 		 */
309 		return TX_DROP;
310 
311 	if (tx->sdata->vif.type == NL80211_IFTYPE_OCB)
312 		return TX_CONTINUE;
313 
314 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
315 		return TX_CONTINUE;
316 
317 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
318 		return TX_CONTINUE;
319 
320 	if (tx->sta)
321 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
322 
323 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
324 		if (unlikely(!assoc &&
325 			     ieee80211_is_data(hdr->frame_control))) {
326 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
327 			sdata_info(tx->sdata,
328 				   "dropped data frame to not associated station %pM\n",
329 				   hdr->addr1);
330 #endif
331 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
332 			return TX_DROP;
333 		}
334 	} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
335 			    ieee80211_is_data(hdr->frame_control) &&
336 			    !atomic_read(&tx->sdata->u.ap.num_mcast_sta))) {
337 		/*
338 		 * No associated STAs - no need to send multicast
339 		 * frames.
340 		 */
341 		return TX_DROP;
342 	}
343 
344 	return TX_CONTINUE;
345 }
346 
347 /* This function is called whenever the AP is about to exceed the maximum limit
348  * of buffered frames for power saving STAs. This situation should not really
349  * happen often during normal operation, so dropping the oldest buffered packet
350  * from each queue should be OK to make some room for new frames. */
351 static void purge_old_ps_buffers(struct ieee80211_local *local)
352 {
353 	int total = 0, purged = 0;
354 	struct sk_buff *skb;
355 	struct ieee80211_sub_if_data *sdata;
356 	struct sta_info *sta;
357 
358 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
359 		struct ps_data *ps;
360 
361 		if (sdata->vif.type == NL80211_IFTYPE_AP)
362 			ps = &sdata->u.ap.ps;
363 		else if (ieee80211_vif_is_mesh(&sdata->vif))
364 			ps = &sdata->u.mesh.ps;
365 		else
366 			continue;
367 
368 		skb = skb_dequeue(&ps->bc_buf);
369 		if (skb) {
370 			purged++;
371 			ieee80211_free_txskb(&local->hw, skb);
372 		}
373 		total += skb_queue_len(&ps->bc_buf);
374 	}
375 
376 	/*
377 	 * Drop one frame from each station from the lowest-priority
378 	 * AC that has frames at all.
379 	 */
380 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
381 		int ac;
382 
383 		for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
384 			skb = skb_dequeue(&sta->ps_tx_buf[ac]);
385 			total += skb_queue_len(&sta->ps_tx_buf[ac]);
386 			if (skb) {
387 				purged++;
388 				ieee80211_free_txskb(&local->hw, skb);
389 				break;
390 			}
391 		}
392 	}
393 
394 	local->total_ps_buffered = total;
395 	ps_dbg_hw(&local->hw, "PS buffers full - purged %d frames\n", purged);
396 }
397 
398 static ieee80211_tx_result
399 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
400 {
401 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
402 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
403 	struct ps_data *ps;
404 
405 	/*
406 	 * broadcast/multicast frame
407 	 *
408 	 * If any of the associated/peer stations is in power save mode,
409 	 * the frame is buffered to be sent after DTIM beacon frame.
410 	 * This is done either by the hardware or us.
411 	 */
412 
413 	/* powersaving STAs currently only in AP/VLAN/mesh mode */
414 	if (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
415 	    tx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
416 		if (!tx->sdata->bss)
417 			return TX_CONTINUE;
418 
419 		ps = &tx->sdata->bss->ps;
420 	} else if (ieee80211_vif_is_mesh(&tx->sdata->vif)) {
421 		ps = &tx->sdata->u.mesh.ps;
422 	} else {
423 		return TX_CONTINUE;
424 	}
425 
426 
427 	/* no buffering for ordered frames */
428 	if (ieee80211_has_order(hdr->frame_control))
429 		return TX_CONTINUE;
430 
431 	if (ieee80211_is_probe_req(hdr->frame_control))
432 		return TX_CONTINUE;
433 
434 	if (ieee80211_hw_check(&tx->local->hw, QUEUE_CONTROL))
435 		info->hw_queue = tx->sdata->vif.cab_queue;
436 
437 	/* no stations in PS mode */
438 	if (!atomic_read(&ps->num_sta_ps))
439 		return TX_CONTINUE;
440 
441 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
442 
443 	/* device releases frame after DTIM beacon */
444 	if (!ieee80211_hw_check(&tx->local->hw, HOST_BROADCAST_PS_BUFFERING))
445 		return TX_CONTINUE;
446 
447 	/* buffered in mac80211 */
448 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
449 		purge_old_ps_buffers(tx->local);
450 
451 	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
452 		ps_dbg(tx->sdata,
453 		       "BC TX buffer full - dropping the oldest frame\n");
454 		ieee80211_free_txskb(&tx->local->hw, skb_dequeue(&ps->bc_buf));
455 	} else
456 		tx->local->total_ps_buffered++;
457 
458 	skb_queue_tail(&ps->bc_buf, tx->skb);
459 
460 	return TX_QUEUED;
461 }
462 
463 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
464 			     struct sk_buff *skb)
465 {
466 	if (!ieee80211_is_mgmt(fc))
467 		return 0;
468 
469 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
470 		return 0;
471 
472 	if (!ieee80211_is_robust_mgmt_frame(skb))
473 		return 0;
474 
475 	return 1;
476 }
477 
478 static ieee80211_tx_result
479 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
480 {
481 	struct sta_info *sta = tx->sta;
482 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
483 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
484 	struct ieee80211_local *local = tx->local;
485 
486 	if (unlikely(!sta))
487 		return TX_CONTINUE;
488 
489 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
490 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
491 		      test_sta_flag(sta, WLAN_STA_PS_DELIVER)) &&
492 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
493 		int ac = skb_get_queue_mapping(tx->skb);
494 
495 		if (ieee80211_is_mgmt(hdr->frame_control) &&
496 		    !ieee80211_is_bufferable_mmpdu(hdr->frame_control)) {
497 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
498 			return TX_CONTINUE;
499 		}
500 
501 		ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
502 		       sta->sta.addr, sta->sta.aid, ac);
503 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
504 			purge_old_ps_buffers(tx->local);
505 
506 		/* sync with ieee80211_sta_ps_deliver_wakeup */
507 		spin_lock(&sta->ps_lock);
508 		/*
509 		 * STA woke up the meantime and all the frames on ps_tx_buf have
510 		 * been queued to pending queue. No reordering can happen, go
511 		 * ahead and Tx the packet.
512 		 */
513 		if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
514 		    !test_sta_flag(sta, WLAN_STA_PS_DRIVER) &&
515 		    !test_sta_flag(sta, WLAN_STA_PS_DELIVER)) {
516 			spin_unlock(&sta->ps_lock);
517 			return TX_CONTINUE;
518 		}
519 
520 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
521 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
522 			ps_dbg(tx->sdata,
523 			       "STA %pM TX buffer for AC %d full - dropping oldest frame\n",
524 			       sta->sta.addr, ac);
525 			ieee80211_free_txskb(&local->hw, old);
526 		} else
527 			tx->local->total_ps_buffered++;
528 
529 		info->control.jiffies = jiffies;
530 		info->control.vif = &tx->sdata->vif;
531 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
532 		info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
533 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
534 		spin_unlock(&sta->ps_lock);
535 
536 		if (!timer_pending(&local->sta_cleanup))
537 			mod_timer(&local->sta_cleanup,
538 				  round_jiffies(jiffies +
539 						STA_INFO_CLEANUP_INTERVAL));
540 
541 		/*
542 		 * We queued up some frames, so the TIM bit might
543 		 * need to be set, recalculate it.
544 		 */
545 		sta_info_recalc_tim(sta);
546 
547 		return TX_QUEUED;
548 	} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
549 		ps_dbg(tx->sdata,
550 		       "STA %pM in PS mode, but polling/in SP -> send frame\n",
551 		       sta->sta.addr);
552 	}
553 
554 	return TX_CONTINUE;
555 }
556 
557 static ieee80211_tx_result debug_noinline
558 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
559 {
560 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
561 		return TX_CONTINUE;
562 
563 	if (tx->flags & IEEE80211_TX_UNICAST)
564 		return ieee80211_tx_h_unicast_ps_buf(tx);
565 	else
566 		return ieee80211_tx_h_multicast_ps_buf(tx);
567 }
568 
569 static ieee80211_tx_result debug_noinline
570 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
571 {
572 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
573 
574 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol)) {
575 		if (tx->sdata->control_port_no_encrypt)
576 			info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
577 		info->control.flags |= IEEE80211_TX_CTRL_PORT_CTRL_PROTO;
578 		info->flags |= IEEE80211_TX_CTL_USE_MINRATE;
579 	}
580 
581 	return TX_CONTINUE;
582 }
583 
584 static ieee80211_tx_result debug_noinline
585 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
586 {
587 	struct ieee80211_key *key;
588 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
589 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
590 
591 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
592 		tx->key = NULL;
593 	else if (tx->sta &&
594 		 (key = rcu_dereference(tx->sta->ptk[tx->sta->ptk_idx])))
595 		tx->key = key;
596 	else if (ieee80211_is_group_privacy_action(tx->skb) &&
597 		(key = rcu_dereference(tx->sdata->default_multicast_key)))
598 		tx->key = key;
599 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
600 		 is_multicast_ether_addr(hdr->addr1) &&
601 		 ieee80211_is_robust_mgmt_frame(tx->skb) &&
602 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
603 		tx->key = key;
604 	else if (is_multicast_ether_addr(hdr->addr1) &&
605 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
606 		tx->key = key;
607 	else if (!is_multicast_ether_addr(hdr->addr1) &&
608 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
609 		tx->key = key;
610 	else
611 		tx->key = NULL;
612 
613 	if (tx->key) {
614 		bool skip_hw = false;
615 
616 		/* TODO: add threshold stuff again */
617 
618 		switch (tx->key->conf.cipher) {
619 		case WLAN_CIPHER_SUITE_WEP40:
620 		case WLAN_CIPHER_SUITE_WEP104:
621 		case WLAN_CIPHER_SUITE_TKIP:
622 			if (!ieee80211_is_data_present(hdr->frame_control))
623 				tx->key = NULL;
624 			break;
625 		case WLAN_CIPHER_SUITE_CCMP:
626 		case WLAN_CIPHER_SUITE_CCMP_256:
627 		case WLAN_CIPHER_SUITE_GCMP:
628 		case WLAN_CIPHER_SUITE_GCMP_256:
629 			if (!ieee80211_is_data_present(hdr->frame_control) &&
630 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
631 					       tx->skb) &&
632 			    !ieee80211_is_group_privacy_action(tx->skb))
633 				tx->key = NULL;
634 			else
635 				skip_hw = (tx->key->conf.flags &
636 					   IEEE80211_KEY_FLAG_SW_MGMT_TX) &&
637 					ieee80211_is_mgmt(hdr->frame_control);
638 			break;
639 		case WLAN_CIPHER_SUITE_AES_CMAC:
640 		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
641 		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
642 		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
643 			if (!ieee80211_is_mgmt(hdr->frame_control))
644 				tx->key = NULL;
645 			break;
646 		}
647 
648 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED &&
649 			     !ieee80211_is_deauth(hdr->frame_control)))
650 			return TX_DROP;
651 
652 		if (!skip_hw && tx->key &&
653 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
654 			info->control.hw_key = &tx->key->conf;
655 	}
656 
657 	return TX_CONTINUE;
658 }
659 
660 static ieee80211_tx_result debug_noinline
661 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
662 {
663 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
664 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
665 	struct ieee80211_supported_band *sband;
666 	u32 len;
667 	struct ieee80211_tx_rate_control txrc;
668 	struct ieee80211_sta_rates *ratetbl = NULL;
669 	bool assoc = false;
670 
671 	memset(&txrc, 0, sizeof(txrc));
672 
673 	sband = tx->local->hw.wiphy->bands[info->band];
674 
675 	len = min_t(u32, tx->skb->len + FCS_LEN,
676 			 tx->local->hw.wiphy->frag_threshold);
677 
678 	/* set up the tx rate control struct we give the RC algo */
679 	txrc.hw = &tx->local->hw;
680 	txrc.sband = sband;
681 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
682 	txrc.skb = tx->skb;
683 	txrc.reported_rate.idx = -1;
684 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
685 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
686 		txrc.max_rate_idx = -1;
687 	else
688 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
689 
690 	if (tx->sdata->rc_has_mcs_mask[info->band])
691 		txrc.rate_idx_mcs_mask =
692 			tx->sdata->rc_rateidx_mcs_mask[info->band];
693 
694 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
695 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
696 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC ||
697 		    tx->sdata->vif.type == NL80211_IFTYPE_OCB);
698 
699 	/* set up RTS protection if desired */
700 	if (len > tx->local->hw.wiphy->rts_threshold) {
701 		txrc.rts = true;
702 	}
703 
704 	info->control.use_rts = txrc.rts;
705 	info->control.use_cts_prot = tx->sdata->vif.bss_conf.use_cts_prot;
706 
707 	/*
708 	 * Use short preamble if the BSS can handle it, but not for
709 	 * management frames unless we know the receiver can handle
710 	 * that -- the management frame might be to a station that
711 	 * just wants a probe response.
712 	 */
713 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
714 	    (ieee80211_is_data(hdr->frame_control) ||
715 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
716 		txrc.short_preamble = true;
717 
718 	info->control.short_preamble = txrc.short_preamble;
719 
720 	/* don't ask rate control when rate already injected via radiotap */
721 	if (info->control.flags & IEEE80211_TX_CTRL_RATE_INJECT)
722 		return TX_CONTINUE;
723 
724 	if (tx->sta)
725 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
726 
727 	/*
728 	 * Lets not bother rate control if we're associated and cannot
729 	 * talk to the sta. This should not happen.
730 	 */
731 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
732 		 !rate_usable_index_exists(sband, &tx->sta->sta),
733 		 "%s: Dropped data frame as no usable bitrate found while "
734 		 "scanning and associated. Target station: "
735 		 "%pM on %d GHz band\n",
736 		 tx->sdata->name, hdr->addr1,
737 		 info->band ? 5 : 2))
738 		return TX_DROP;
739 
740 	/*
741 	 * If we're associated with the sta at this point we know we can at
742 	 * least send the frame at the lowest bit rate.
743 	 */
744 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
745 
746 	if (tx->sta && !info->control.skip_table)
747 		ratetbl = rcu_dereference(tx->sta->sta.rates);
748 
749 	if (unlikely(info->control.rates[0].idx < 0)) {
750 		if (ratetbl) {
751 			struct ieee80211_tx_rate rate = {
752 				.idx = ratetbl->rate[0].idx,
753 				.flags = ratetbl->rate[0].flags,
754 				.count = ratetbl->rate[0].count
755 			};
756 
757 			if (ratetbl->rate[0].idx < 0)
758 				return TX_DROP;
759 
760 			tx->rate = rate;
761 		} else {
762 			return TX_DROP;
763 		}
764 	} else {
765 		tx->rate = info->control.rates[0];
766 	}
767 
768 	if (txrc.reported_rate.idx < 0) {
769 		txrc.reported_rate = tx->rate;
770 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
771 			tx->sta->tx_stats.last_rate = txrc.reported_rate;
772 	} else if (tx->sta)
773 		tx->sta->tx_stats.last_rate = txrc.reported_rate;
774 
775 	if (ratetbl)
776 		return TX_CONTINUE;
777 
778 	if (unlikely(!info->control.rates[0].count))
779 		info->control.rates[0].count = 1;
780 
781 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
782 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
783 		info->control.rates[0].count = 1;
784 
785 	return TX_CONTINUE;
786 }
787 
788 static __le16 ieee80211_tx_next_seq(struct sta_info *sta, int tid)
789 {
790 	u16 *seq = &sta->tid_seq[tid];
791 	__le16 ret = cpu_to_le16(*seq);
792 
793 	/* Increase the sequence number. */
794 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
795 
796 	return ret;
797 }
798 
799 static ieee80211_tx_result debug_noinline
800 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
801 {
802 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
803 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
804 	u8 *qc;
805 	int tid;
806 
807 	/*
808 	 * Packet injection may want to control the sequence
809 	 * number, if we have no matching interface then we
810 	 * neither assign one ourselves nor ask the driver to.
811 	 */
812 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
813 		return TX_CONTINUE;
814 
815 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
816 		return TX_CONTINUE;
817 
818 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
819 		return TX_CONTINUE;
820 
821 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
822 		return TX_CONTINUE;
823 
824 	/*
825 	 * Anything but QoS data that has a sequence number field
826 	 * (is long enough) gets a sequence number from the global
827 	 * counter.  QoS data frames with a multicast destination
828 	 * also use the global counter (802.11-2012 9.3.2.10).
829 	 */
830 	if (!ieee80211_is_data_qos(hdr->frame_control) ||
831 	    is_multicast_ether_addr(hdr->addr1)) {
832 		/* driver should assign sequence number */
833 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
834 		/* for pure STA mode without beacons, we can do it */
835 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
836 		tx->sdata->sequence_number += 0x10;
837 		if (tx->sta)
838 			tx->sta->tx_stats.msdu[IEEE80211_NUM_TIDS]++;
839 		return TX_CONTINUE;
840 	}
841 
842 	/*
843 	 * This should be true for injected/management frames only, for
844 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
845 	 * above since they are not QoS-data frames.
846 	 */
847 	if (!tx->sta)
848 		return TX_CONTINUE;
849 
850 	/* include per-STA, per-TID sequence counter */
851 
852 	qc = ieee80211_get_qos_ctl(hdr);
853 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
854 	tx->sta->tx_stats.msdu[tid]++;
855 
856 	if (!tx->sta->sta.txq[0])
857 		hdr->seq_ctrl = ieee80211_tx_next_seq(tx->sta, tid);
858 
859 	return TX_CONTINUE;
860 }
861 
862 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
863 			      struct sk_buff *skb, int hdrlen,
864 			      int frag_threshold)
865 {
866 	struct ieee80211_local *local = tx->local;
867 	struct ieee80211_tx_info *info;
868 	struct sk_buff *tmp;
869 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
870 	int pos = hdrlen + per_fragm;
871 	int rem = skb->len - hdrlen - per_fragm;
872 
873 	if (WARN_ON(rem < 0))
874 		return -EINVAL;
875 
876 	/* first fragment was already added to queue by caller */
877 
878 	while (rem) {
879 		int fraglen = per_fragm;
880 
881 		if (fraglen > rem)
882 			fraglen = rem;
883 		rem -= fraglen;
884 		tmp = dev_alloc_skb(local->tx_headroom +
885 				    frag_threshold +
886 				    tx->sdata->encrypt_headroom +
887 				    IEEE80211_ENCRYPT_TAILROOM);
888 		if (!tmp)
889 			return -ENOMEM;
890 
891 		__skb_queue_tail(&tx->skbs, tmp);
892 
893 		skb_reserve(tmp,
894 			    local->tx_headroom + tx->sdata->encrypt_headroom);
895 
896 		/* copy control information */
897 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
898 
899 		info = IEEE80211_SKB_CB(tmp);
900 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
901 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
902 
903 		if (rem)
904 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
905 
906 		skb_copy_queue_mapping(tmp, skb);
907 		tmp->priority = skb->priority;
908 		tmp->dev = skb->dev;
909 
910 		/* copy header and data */
911 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
912 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
913 
914 		pos += fraglen;
915 	}
916 
917 	/* adjust first fragment's length */
918 	skb_trim(skb, hdrlen + per_fragm);
919 	return 0;
920 }
921 
922 static ieee80211_tx_result debug_noinline
923 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
924 {
925 	struct sk_buff *skb = tx->skb;
926 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
927 	struct ieee80211_hdr *hdr = (void *)skb->data;
928 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
929 	int hdrlen;
930 	int fragnum;
931 
932 	/* no matter what happens, tx->skb moves to tx->skbs */
933 	__skb_queue_tail(&tx->skbs, skb);
934 	tx->skb = NULL;
935 
936 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
937 		return TX_CONTINUE;
938 
939 	if (tx->local->ops->set_frag_threshold)
940 		return TX_CONTINUE;
941 
942 	/*
943 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
944 	 * This scenario is handled in ieee80211_tx_prepare but extra
945 	 * caution taken here as fragmented ampdu may cause Tx stop.
946 	 */
947 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
948 		return TX_DROP;
949 
950 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
951 
952 	/* internal error, why isn't DONTFRAG set? */
953 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
954 		return TX_DROP;
955 
956 	/*
957 	 * Now fragment the frame. This will allocate all the fragments and
958 	 * chain them (using skb as the first fragment) to skb->next.
959 	 * During transmission, we will remove the successfully transmitted
960 	 * fragments from this list. When the low-level driver rejects one
961 	 * of the fragments then we will simply pretend to accept the skb
962 	 * but store it away as pending.
963 	 */
964 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
965 		return TX_DROP;
966 
967 	/* update duration/seq/flags of fragments */
968 	fragnum = 0;
969 
970 	skb_queue_walk(&tx->skbs, skb) {
971 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
972 
973 		hdr = (void *)skb->data;
974 		info = IEEE80211_SKB_CB(skb);
975 
976 		if (!skb_queue_is_last(&tx->skbs, skb)) {
977 			hdr->frame_control |= morefrags;
978 			/*
979 			 * No multi-rate retries for fragmented frames, that
980 			 * would completely throw off the NAV at other STAs.
981 			 */
982 			info->control.rates[1].idx = -1;
983 			info->control.rates[2].idx = -1;
984 			info->control.rates[3].idx = -1;
985 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 4);
986 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
987 		} else {
988 			hdr->frame_control &= ~morefrags;
989 		}
990 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
991 		fragnum++;
992 	}
993 
994 	return TX_CONTINUE;
995 }
996 
997 static ieee80211_tx_result debug_noinline
998 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
999 {
1000 	struct sk_buff *skb;
1001 	int ac = -1;
1002 
1003 	if (!tx->sta)
1004 		return TX_CONTINUE;
1005 
1006 	skb_queue_walk(&tx->skbs, skb) {
1007 		ac = skb_get_queue_mapping(skb);
1008 		tx->sta->tx_stats.bytes[ac] += skb->len;
1009 	}
1010 	if (ac >= 0)
1011 		tx->sta->tx_stats.packets[ac]++;
1012 
1013 	return TX_CONTINUE;
1014 }
1015 
1016 static ieee80211_tx_result debug_noinline
1017 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
1018 {
1019 	if (!tx->key)
1020 		return TX_CONTINUE;
1021 
1022 	switch (tx->key->conf.cipher) {
1023 	case WLAN_CIPHER_SUITE_WEP40:
1024 	case WLAN_CIPHER_SUITE_WEP104:
1025 		return ieee80211_crypto_wep_encrypt(tx);
1026 	case WLAN_CIPHER_SUITE_TKIP:
1027 		return ieee80211_crypto_tkip_encrypt(tx);
1028 	case WLAN_CIPHER_SUITE_CCMP:
1029 		return ieee80211_crypto_ccmp_encrypt(
1030 			tx, IEEE80211_CCMP_MIC_LEN);
1031 	case WLAN_CIPHER_SUITE_CCMP_256:
1032 		return ieee80211_crypto_ccmp_encrypt(
1033 			tx, IEEE80211_CCMP_256_MIC_LEN);
1034 	case WLAN_CIPHER_SUITE_AES_CMAC:
1035 		return ieee80211_crypto_aes_cmac_encrypt(tx);
1036 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1037 		return ieee80211_crypto_aes_cmac_256_encrypt(tx);
1038 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1039 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1040 		return ieee80211_crypto_aes_gmac_encrypt(tx);
1041 	case WLAN_CIPHER_SUITE_GCMP:
1042 	case WLAN_CIPHER_SUITE_GCMP_256:
1043 		return ieee80211_crypto_gcmp_encrypt(tx);
1044 	default:
1045 		return ieee80211_crypto_hw_encrypt(tx);
1046 	}
1047 
1048 	return TX_DROP;
1049 }
1050 
1051 static ieee80211_tx_result debug_noinline
1052 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
1053 {
1054 	struct sk_buff *skb;
1055 	struct ieee80211_hdr *hdr;
1056 	int next_len;
1057 	bool group_addr;
1058 
1059 	skb_queue_walk(&tx->skbs, skb) {
1060 		hdr = (void *) skb->data;
1061 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
1062 			break; /* must not overwrite AID */
1063 		if (!skb_queue_is_last(&tx->skbs, skb)) {
1064 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
1065 			next_len = next->len;
1066 		} else
1067 			next_len = 0;
1068 		group_addr = is_multicast_ether_addr(hdr->addr1);
1069 
1070 		hdr->duration_id =
1071 			ieee80211_duration(tx, skb, group_addr, next_len);
1072 	}
1073 
1074 	return TX_CONTINUE;
1075 }
1076 
1077 /* actual transmit path */
1078 
1079 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1080 				  struct sk_buff *skb,
1081 				  struct ieee80211_tx_info *info,
1082 				  struct tid_ampdu_tx *tid_tx,
1083 				  int tid)
1084 {
1085 	bool queued = false;
1086 	bool reset_agg_timer = false;
1087 	struct sk_buff *purge_skb = NULL;
1088 
1089 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1090 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1091 		reset_agg_timer = true;
1092 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1093 		/*
1094 		 * nothing -- this aggregation session is being started
1095 		 * but that might still fail with the driver
1096 		 */
1097 	} else if (!tx->sta->sta.txq[tid]) {
1098 		spin_lock(&tx->sta->lock);
1099 		/*
1100 		 * Need to re-check now, because we may get here
1101 		 *
1102 		 *  1) in the window during which the setup is actually
1103 		 *     already done, but not marked yet because not all
1104 		 *     packets are spliced over to the driver pending
1105 		 *     queue yet -- if this happened we acquire the lock
1106 		 *     either before or after the splice happens, but
1107 		 *     need to recheck which of these cases happened.
1108 		 *
1109 		 *  2) during session teardown, if the OPERATIONAL bit
1110 		 *     was cleared due to the teardown but the pointer
1111 		 *     hasn't been assigned NULL yet (or we loaded it
1112 		 *     before it was assigned) -- in this case it may
1113 		 *     now be NULL which means we should just let the
1114 		 *     packet pass through because splicing the frames
1115 		 *     back is already done.
1116 		 */
1117 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1118 
1119 		if (!tid_tx) {
1120 			/* do nothing, let packet pass through */
1121 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1122 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1123 			reset_agg_timer = true;
1124 		} else {
1125 			queued = true;
1126 			if (info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER) {
1127 				clear_sta_flag(tx->sta, WLAN_STA_SP);
1128 				ps_dbg(tx->sta->sdata,
1129 				       "STA %pM aid %d: SP frame queued, close the SP w/o telling the peer\n",
1130 				       tx->sta->sta.addr, tx->sta->sta.aid);
1131 			}
1132 			info->control.vif = &tx->sdata->vif;
1133 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1134 			info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
1135 			__skb_queue_tail(&tid_tx->pending, skb);
1136 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1137 				purge_skb = __skb_dequeue(&tid_tx->pending);
1138 		}
1139 		spin_unlock(&tx->sta->lock);
1140 
1141 		if (purge_skb)
1142 			ieee80211_free_txskb(&tx->local->hw, purge_skb);
1143 	}
1144 
1145 	/* reset session timer */
1146 	if (reset_agg_timer && tid_tx->timeout)
1147 		tid_tx->last_tx = jiffies;
1148 
1149 	return queued;
1150 }
1151 
1152 /*
1153  * initialises @tx
1154  * pass %NULL for the station if unknown, a valid pointer if known
1155  * or an ERR_PTR() if the station is known not to exist
1156  */
1157 static ieee80211_tx_result
1158 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1159 		     struct ieee80211_tx_data *tx,
1160 		     struct sta_info *sta, struct sk_buff *skb)
1161 {
1162 	struct ieee80211_local *local = sdata->local;
1163 	struct ieee80211_hdr *hdr;
1164 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1165 	int tid;
1166 	u8 *qc;
1167 
1168 	memset(tx, 0, sizeof(*tx));
1169 	tx->skb = skb;
1170 	tx->local = local;
1171 	tx->sdata = sdata;
1172 	__skb_queue_head_init(&tx->skbs);
1173 
1174 	/*
1175 	 * If this flag is set to true anywhere, and we get here,
1176 	 * we are doing the needed processing, so remove the flag
1177 	 * now.
1178 	 */
1179 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1180 
1181 	hdr = (struct ieee80211_hdr *) skb->data;
1182 
1183 	if (likely(sta)) {
1184 		if (!IS_ERR(sta))
1185 			tx->sta = sta;
1186 	} else {
1187 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1188 			tx->sta = rcu_dereference(sdata->u.vlan.sta);
1189 			if (!tx->sta && sdata->wdev.use_4addr)
1190 				return TX_DROP;
1191 		} else if (info->flags & (IEEE80211_TX_INTFL_NL80211_FRAME_TX |
1192 					  IEEE80211_TX_CTL_INJECTED) ||
1193 			   tx->sdata->control_port_protocol == tx->skb->protocol) {
1194 			tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1195 		}
1196 		if (!tx->sta && !is_multicast_ether_addr(hdr->addr1))
1197 			tx->sta = sta_info_get(sdata, hdr->addr1);
1198 	}
1199 
1200 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1201 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1202 	    ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
1203 	    !ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW)) {
1204 		struct tid_ampdu_tx *tid_tx;
1205 
1206 		qc = ieee80211_get_qos_ctl(hdr);
1207 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1208 
1209 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1210 		if (tid_tx) {
1211 			bool queued;
1212 
1213 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1214 						       tid_tx, tid);
1215 
1216 			if (unlikely(queued))
1217 				return TX_QUEUED;
1218 		}
1219 	}
1220 
1221 	if (is_multicast_ether_addr(hdr->addr1)) {
1222 		tx->flags &= ~IEEE80211_TX_UNICAST;
1223 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1224 	} else
1225 		tx->flags |= IEEE80211_TX_UNICAST;
1226 
1227 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1228 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1229 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1230 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1231 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1232 	}
1233 
1234 	if (!tx->sta)
1235 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1236 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT)) {
1237 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1238 		ieee80211_check_fast_xmit(tx->sta);
1239 	}
1240 
1241 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1242 
1243 	return TX_CONTINUE;
1244 }
1245 
1246 static struct txq_info *ieee80211_get_txq(struct ieee80211_local *local,
1247 					  struct ieee80211_vif *vif,
1248 					  struct ieee80211_sta *pubsta,
1249 					  struct sk_buff *skb)
1250 {
1251 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1252 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1253 	struct ieee80211_txq *txq = NULL;
1254 
1255 	if ((info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) ||
1256 	    (info->control.flags & IEEE80211_TX_CTRL_PS_RESPONSE))
1257 		return NULL;
1258 
1259 	if (!ieee80211_is_data(hdr->frame_control))
1260 		return NULL;
1261 
1262 	if (pubsta) {
1263 		u8 tid = skb->priority & IEEE80211_QOS_CTL_TID_MASK;
1264 
1265 		txq = pubsta->txq[tid];
1266 	} else if (vif) {
1267 		txq = vif->txq;
1268 	}
1269 
1270 	if (!txq)
1271 		return NULL;
1272 
1273 	return to_txq_info(txq);
1274 }
1275 
1276 static void ieee80211_set_skb_enqueue_time(struct sk_buff *skb)
1277 {
1278 	IEEE80211_SKB_CB(skb)->control.enqueue_time = codel_get_time();
1279 }
1280 
1281 static void ieee80211_set_skb_vif(struct sk_buff *skb, struct txq_info *txqi)
1282 {
1283 	IEEE80211_SKB_CB(skb)->control.vif = txqi->txq.vif;
1284 }
1285 
1286 static u32 codel_skb_len_func(const struct sk_buff *skb)
1287 {
1288 	return skb->len;
1289 }
1290 
1291 static codel_time_t codel_skb_time_func(const struct sk_buff *skb)
1292 {
1293 	const struct ieee80211_tx_info *info;
1294 
1295 	info = (const struct ieee80211_tx_info *)skb->cb;
1296 	return info->control.enqueue_time;
1297 }
1298 
1299 static struct sk_buff *codel_dequeue_func(struct codel_vars *cvars,
1300 					  void *ctx)
1301 {
1302 	struct ieee80211_local *local;
1303 	struct txq_info *txqi;
1304 	struct fq *fq;
1305 	struct fq_flow *flow;
1306 
1307 	txqi = ctx;
1308 	local = vif_to_sdata(txqi->txq.vif)->local;
1309 	fq = &local->fq;
1310 
1311 	if (cvars == &txqi->def_cvars)
1312 		flow = &txqi->def_flow;
1313 	else
1314 		flow = &fq->flows[cvars - local->cvars];
1315 
1316 	return fq_flow_dequeue(fq, flow);
1317 }
1318 
1319 static void codel_drop_func(struct sk_buff *skb,
1320 			    void *ctx)
1321 {
1322 	struct ieee80211_local *local;
1323 	struct ieee80211_hw *hw;
1324 	struct txq_info *txqi;
1325 
1326 	txqi = ctx;
1327 	local = vif_to_sdata(txqi->txq.vif)->local;
1328 	hw = &local->hw;
1329 
1330 	ieee80211_free_txskb(hw, skb);
1331 }
1332 
1333 static struct sk_buff *fq_tin_dequeue_func(struct fq *fq,
1334 					   struct fq_tin *tin,
1335 					   struct fq_flow *flow)
1336 {
1337 	struct ieee80211_local *local;
1338 	struct txq_info *txqi;
1339 	struct codel_vars *cvars;
1340 	struct codel_params *cparams;
1341 	struct codel_stats *cstats;
1342 
1343 	local = container_of(fq, struct ieee80211_local, fq);
1344 	txqi = container_of(tin, struct txq_info, tin);
1345 	cparams = &local->cparams;
1346 	cstats = &local->cstats;
1347 
1348 	if (flow == &txqi->def_flow)
1349 		cvars = &txqi->def_cvars;
1350 	else
1351 		cvars = &local->cvars[flow - fq->flows];
1352 
1353 	return codel_dequeue(txqi,
1354 			     &flow->backlog,
1355 			     cparams,
1356 			     cvars,
1357 			     cstats,
1358 			     codel_skb_len_func,
1359 			     codel_skb_time_func,
1360 			     codel_drop_func,
1361 			     codel_dequeue_func);
1362 }
1363 
1364 static void fq_skb_free_func(struct fq *fq,
1365 			     struct fq_tin *tin,
1366 			     struct fq_flow *flow,
1367 			     struct sk_buff *skb)
1368 {
1369 	struct ieee80211_local *local;
1370 
1371 	local = container_of(fq, struct ieee80211_local, fq);
1372 	ieee80211_free_txskb(&local->hw, skb);
1373 }
1374 
1375 static struct fq_flow *fq_flow_get_default_func(struct fq *fq,
1376 						struct fq_tin *tin,
1377 						int idx,
1378 						struct sk_buff *skb)
1379 {
1380 	struct txq_info *txqi;
1381 
1382 	txqi = container_of(tin, struct txq_info, tin);
1383 	return &txqi->def_flow;
1384 }
1385 
1386 static void ieee80211_txq_enqueue(struct ieee80211_local *local,
1387 				  struct txq_info *txqi,
1388 				  struct sk_buff *skb)
1389 {
1390 	struct fq *fq = &local->fq;
1391 	struct fq_tin *tin = &txqi->tin;
1392 
1393 	ieee80211_set_skb_enqueue_time(skb);
1394 	fq_tin_enqueue(fq, tin, skb,
1395 		       fq_skb_free_func,
1396 		       fq_flow_get_default_func);
1397 }
1398 
1399 void ieee80211_txq_init(struct ieee80211_sub_if_data *sdata,
1400 			struct sta_info *sta,
1401 			struct txq_info *txqi, int tid)
1402 {
1403 	fq_tin_init(&txqi->tin);
1404 	fq_flow_init(&txqi->def_flow);
1405 	codel_vars_init(&txqi->def_cvars);
1406 
1407 	txqi->txq.vif = &sdata->vif;
1408 
1409 	if (sta) {
1410 		txqi->txq.sta = &sta->sta;
1411 		sta->sta.txq[tid] = &txqi->txq;
1412 		txqi->txq.tid = tid;
1413 		txqi->txq.ac = ieee802_1d_to_ac[tid & 7];
1414 	} else {
1415 		sdata->vif.txq = &txqi->txq;
1416 		txqi->txq.tid = 0;
1417 		txqi->txq.ac = IEEE80211_AC_BE;
1418 	}
1419 }
1420 
1421 void ieee80211_txq_purge(struct ieee80211_local *local,
1422 			 struct txq_info *txqi)
1423 {
1424 	struct fq *fq = &local->fq;
1425 	struct fq_tin *tin = &txqi->tin;
1426 
1427 	fq_tin_reset(fq, tin, fq_skb_free_func);
1428 }
1429 
1430 int ieee80211_txq_setup_flows(struct ieee80211_local *local)
1431 {
1432 	struct fq *fq = &local->fq;
1433 	int ret;
1434 	int i;
1435 
1436 	if (!local->ops->wake_tx_queue)
1437 		return 0;
1438 
1439 	ret = fq_init(fq, 4096);
1440 	if (ret)
1441 		return ret;
1442 
1443 	codel_params_init(&local->cparams);
1444 	codel_stats_init(&local->cstats);
1445 	local->cparams.interval = MS2TIME(100);
1446 	local->cparams.target = MS2TIME(20);
1447 	local->cparams.ecn = true;
1448 
1449 	local->cvars = kcalloc(fq->flows_cnt, sizeof(local->cvars[0]),
1450 			       GFP_KERNEL);
1451 	if (!local->cvars) {
1452 		spin_lock_bh(&fq->lock);
1453 		fq_reset(fq, fq_skb_free_func);
1454 		spin_unlock_bh(&fq->lock);
1455 		return -ENOMEM;
1456 	}
1457 
1458 	for (i = 0; i < fq->flows_cnt; i++)
1459 		codel_vars_init(&local->cvars[i]);
1460 
1461 	return 0;
1462 }
1463 
1464 void ieee80211_txq_teardown_flows(struct ieee80211_local *local)
1465 {
1466 	struct fq *fq = &local->fq;
1467 
1468 	if (!local->ops->wake_tx_queue)
1469 		return;
1470 
1471 	kfree(local->cvars);
1472 	local->cvars = NULL;
1473 
1474 	spin_lock_bh(&fq->lock);
1475 	fq_reset(fq, fq_skb_free_func);
1476 	spin_unlock_bh(&fq->lock);
1477 }
1478 
1479 struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
1480 				     struct ieee80211_txq *txq)
1481 {
1482 	struct ieee80211_local *local = hw_to_local(hw);
1483 	struct txq_info *txqi = container_of(txq, struct txq_info, txq);
1484 	struct ieee80211_hdr *hdr;
1485 	struct sk_buff *skb = NULL;
1486 	struct fq *fq = &local->fq;
1487 	struct fq_tin *tin = &txqi->tin;
1488 
1489 	spin_lock_bh(&fq->lock);
1490 
1491 	if (test_bit(IEEE80211_TXQ_STOP, &txqi->flags))
1492 		goto out;
1493 
1494 	skb = fq_tin_dequeue(fq, tin, fq_tin_dequeue_func);
1495 	if (!skb)
1496 		goto out;
1497 
1498 	ieee80211_set_skb_vif(skb, txqi);
1499 
1500 	hdr = (struct ieee80211_hdr *)skb->data;
1501 	if (txq->sta && ieee80211_is_data_qos(hdr->frame_control)) {
1502 		struct sta_info *sta = container_of(txq->sta, struct sta_info,
1503 						    sta);
1504 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1505 
1506 		hdr->seq_ctrl = ieee80211_tx_next_seq(sta, txq->tid);
1507 		if (test_bit(IEEE80211_TXQ_AMPDU, &txqi->flags))
1508 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1509 		else
1510 			info->flags &= ~IEEE80211_TX_CTL_AMPDU;
1511 	}
1512 
1513 out:
1514 	spin_unlock_bh(&fq->lock);
1515 
1516 	if (skb && skb_has_frag_list(skb) &&
1517 	    !ieee80211_hw_check(&local->hw, TX_FRAG_LIST))
1518 		skb_linearize(skb);
1519 
1520 	return skb;
1521 }
1522 EXPORT_SYMBOL(ieee80211_tx_dequeue);
1523 
1524 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1525 			       struct ieee80211_vif *vif,
1526 			       struct ieee80211_sta *sta,
1527 			       struct sk_buff_head *skbs,
1528 			       bool txpending)
1529 {
1530 	struct ieee80211_tx_control control = {};
1531 	struct fq *fq = &local->fq;
1532 	struct sk_buff *skb, *tmp;
1533 	struct txq_info *txqi;
1534 	unsigned long flags;
1535 
1536 	skb_queue_walk_safe(skbs, skb, tmp) {
1537 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1538 		int q = info->hw_queue;
1539 
1540 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1541 		if (WARN_ON_ONCE(q >= local->hw.queues)) {
1542 			__skb_unlink(skb, skbs);
1543 			ieee80211_free_txskb(&local->hw, skb);
1544 			continue;
1545 		}
1546 #endif
1547 
1548 		txqi = ieee80211_get_txq(local, vif, sta, skb);
1549 		if (txqi) {
1550 			info->control.vif = vif;
1551 
1552 			__skb_unlink(skb, skbs);
1553 
1554 			spin_lock_bh(&fq->lock);
1555 			ieee80211_txq_enqueue(local, txqi, skb);
1556 			spin_unlock_bh(&fq->lock);
1557 
1558 			drv_wake_tx_queue(local, txqi);
1559 
1560 			continue;
1561 		}
1562 
1563 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1564 		if (local->queue_stop_reasons[q] ||
1565 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1566 			if (unlikely(info->flags &
1567 				     IEEE80211_TX_INTFL_OFFCHAN_TX_OK)) {
1568 				if (local->queue_stop_reasons[q] &
1569 				    ~BIT(IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL)) {
1570 					/*
1571 					 * Drop off-channel frames if queues
1572 					 * are stopped for any reason other
1573 					 * than off-channel operation. Never
1574 					 * queue them.
1575 					 */
1576 					spin_unlock_irqrestore(
1577 						&local->queue_stop_reason_lock,
1578 						flags);
1579 					ieee80211_purge_tx_queue(&local->hw,
1580 								 skbs);
1581 					return true;
1582 				}
1583 			} else {
1584 
1585 				/*
1586 				 * Since queue is stopped, queue up frames for
1587 				 * later transmission from the tx-pending
1588 				 * tasklet when the queue is woken again.
1589 				 */
1590 				if (txpending)
1591 					skb_queue_splice_init(skbs,
1592 							      &local->pending[q]);
1593 				else
1594 					skb_queue_splice_tail_init(skbs,
1595 								   &local->pending[q]);
1596 
1597 				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1598 						       flags);
1599 				return false;
1600 			}
1601 		}
1602 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1603 
1604 		info->control.vif = vif;
1605 		control.sta = sta;
1606 
1607 		__skb_unlink(skb, skbs);
1608 		drv_tx(local, &control, skb);
1609 	}
1610 
1611 	return true;
1612 }
1613 
1614 /*
1615  * Returns false if the frame couldn't be transmitted but was queued instead.
1616  */
1617 static bool __ieee80211_tx(struct ieee80211_local *local,
1618 			   struct sk_buff_head *skbs, int led_len,
1619 			   struct sta_info *sta, bool txpending)
1620 {
1621 	struct ieee80211_tx_info *info;
1622 	struct ieee80211_sub_if_data *sdata;
1623 	struct ieee80211_vif *vif;
1624 	struct ieee80211_sta *pubsta;
1625 	struct sk_buff *skb;
1626 	bool result = true;
1627 	__le16 fc;
1628 
1629 	if (WARN_ON(skb_queue_empty(skbs)))
1630 		return true;
1631 
1632 	skb = skb_peek(skbs);
1633 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1634 	info = IEEE80211_SKB_CB(skb);
1635 	sdata = vif_to_sdata(info->control.vif);
1636 	if (sta && !sta->uploaded)
1637 		sta = NULL;
1638 
1639 	if (sta)
1640 		pubsta = &sta->sta;
1641 	else
1642 		pubsta = NULL;
1643 
1644 	switch (sdata->vif.type) {
1645 	case NL80211_IFTYPE_MONITOR:
1646 		if (sdata->u.mntr_flags & MONITOR_FLAG_ACTIVE) {
1647 			vif = &sdata->vif;
1648 			break;
1649 		}
1650 		sdata = rcu_dereference(local->monitor_sdata);
1651 		if (sdata) {
1652 			vif = &sdata->vif;
1653 			info->hw_queue =
1654 				vif->hw_queue[skb_get_queue_mapping(skb)];
1655 		} else if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL)) {
1656 			ieee80211_purge_tx_queue(&local->hw, skbs);
1657 			return true;
1658 		} else
1659 			vif = NULL;
1660 		break;
1661 	case NL80211_IFTYPE_AP_VLAN:
1662 		sdata = container_of(sdata->bss,
1663 				     struct ieee80211_sub_if_data, u.ap);
1664 		/* fall through */
1665 	default:
1666 		vif = &sdata->vif;
1667 		break;
1668 	}
1669 
1670 	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1671 				    txpending);
1672 
1673 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1674 
1675 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1676 
1677 	return result;
1678 }
1679 
1680 /*
1681  * Invoke TX handlers, return 0 on success and non-zero if the
1682  * frame was dropped or queued.
1683  */
1684 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1685 {
1686 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1687 	ieee80211_tx_result res = TX_DROP;
1688 
1689 #define CALL_TXH(txh) \
1690 	do {				\
1691 		res = txh(tx);		\
1692 		if (res != TX_CONTINUE)	\
1693 			goto txh_done;	\
1694 	} while (0)
1695 
1696 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1697 	CALL_TXH(ieee80211_tx_h_check_assoc);
1698 	CALL_TXH(ieee80211_tx_h_ps_buf);
1699 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1700 	CALL_TXH(ieee80211_tx_h_select_key);
1701 	if (!ieee80211_hw_check(&tx->local->hw, HAS_RATE_CONTROL))
1702 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1703 
1704 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1705 		__skb_queue_tail(&tx->skbs, tx->skb);
1706 		tx->skb = NULL;
1707 		goto txh_done;
1708 	}
1709 
1710 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1711 	CALL_TXH(ieee80211_tx_h_sequence);
1712 	CALL_TXH(ieee80211_tx_h_fragment);
1713 	/* handlers after fragment must be aware of tx info fragmentation! */
1714 	CALL_TXH(ieee80211_tx_h_stats);
1715 	CALL_TXH(ieee80211_tx_h_encrypt);
1716 	if (!ieee80211_hw_check(&tx->local->hw, HAS_RATE_CONTROL))
1717 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1718 #undef CALL_TXH
1719 
1720  txh_done:
1721 	if (unlikely(res == TX_DROP)) {
1722 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1723 		if (tx->skb)
1724 			ieee80211_free_txskb(&tx->local->hw, tx->skb);
1725 		else
1726 			ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
1727 		return -1;
1728 	} else if (unlikely(res == TX_QUEUED)) {
1729 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1730 		return -1;
1731 	}
1732 
1733 	return 0;
1734 }
1735 
1736 bool ieee80211_tx_prepare_skb(struct ieee80211_hw *hw,
1737 			      struct ieee80211_vif *vif, struct sk_buff *skb,
1738 			      int band, struct ieee80211_sta **sta)
1739 {
1740 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1741 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1742 	struct ieee80211_tx_data tx;
1743 	struct sk_buff *skb2;
1744 
1745 	if (ieee80211_tx_prepare(sdata, &tx, NULL, skb) == TX_DROP)
1746 		return false;
1747 
1748 	info->band = band;
1749 	info->control.vif = vif;
1750 	info->hw_queue = vif->hw_queue[skb_get_queue_mapping(skb)];
1751 
1752 	if (invoke_tx_handlers(&tx))
1753 		return false;
1754 
1755 	if (sta) {
1756 		if (tx.sta)
1757 			*sta = &tx.sta->sta;
1758 		else
1759 			*sta = NULL;
1760 	}
1761 
1762 	/* this function isn't suitable for fragmented data frames */
1763 	skb2 = __skb_dequeue(&tx.skbs);
1764 	if (WARN_ON(skb2 != skb || !skb_queue_empty(&tx.skbs))) {
1765 		ieee80211_free_txskb(hw, skb2);
1766 		ieee80211_purge_tx_queue(hw, &tx.skbs);
1767 		return false;
1768 	}
1769 
1770 	return true;
1771 }
1772 EXPORT_SYMBOL(ieee80211_tx_prepare_skb);
1773 
1774 /*
1775  * Returns false if the frame couldn't be transmitted but was queued instead.
1776  */
1777 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1778 			 struct sta_info *sta, struct sk_buff *skb,
1779 			 bool txpending)
1780 {
1781 	struct ieee80211_local *local = sdata->local;
1782 	struct ieee80211_tx_data tx;
1783 	ieee80211_tx_result res_prepare;
1784 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1785 	bool result = true;
1786 	int led_len;
1787 
1788 	if (unlikely(skb->len < 10)) {
1789 		dev_kfree_skb(skb);
1790 		return true;
1791 	}
1792 
1793 	/* initialises tx */
1794 	led_len = skb->len;
1795 	res_prepare = ieee80211_tx_prepare(sdata, &tx, sta, skb);
1796 
1797 	if (unlikely(res_prepare == TX_DROP)) {
1798 		ieee80211_free_txskb(&local->hw, skb);
1799 		return true;
1800 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1801 		return true;
1802 	}
1803 
1804 	/* set up hw_queue value early */
1805 	if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
1806 	    !ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
1807 		info->hw_queue =
1808 			sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
1809 
1810 	if (!invoke_tx_handlers(&tx))
1811 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1812 					tx.sta, txpending);
1813 
1814 	return result;
1815 }
1816 
1817 /* device xmit handlers */
1818 
1819 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1820 				struct sk_buff *skb,
1821 				int head_need, bool may_encrypt)
1822 {
1823 	struct ieee80211_local *local = sdata->local;
1824 	int tail_need = 0;
1825 
1826 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1827 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1828 		tail_need -= skb_tailroom(skb);
1829 		tail_need = max_t(int, tail_need, 0);
1830 	}
1831 
1832 	if (skb_cloned(skb) &&
1833 	    (!ieee80211_hw_check(&local->hw, SUPPORTS_CLONED_SKBS) ||
1834 	     !skb_clone_writable(skb, ETH_HLEN) ||
1835 	     (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt)))
1836 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1837 	else if (head_need || tail_need)
1838 		I802_DEBUG_INC(local->tx_expand_skb_head);
1839 	else
1840 		return 0;
1841 
1842 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1843 		wiphy_debug(local->hw.wiphy,
1844 			    "failed to reallocate TX buffer\n");
1845 		return -ENOMEM;
1846 	}
1847 
1848 	return 0;
1849 }
1850 
1851 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1852 		    struct sta_info *sta, struct sk_buff *skb)
1853 {
1854 	struct ieee80211_local *local = sdata->local;
1855 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1856 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1857 	int headroom;
1858 	bool may_encrypt;
1859 
1860 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1861 
1862 	headroom = local->tx_headroom;
1863 	if (may_encrypt)
1864 		headroom += sdata->encrypt_headroom;
1865 	headroom -= skb_headroom(skb);
1866 	headroom = max_t(int, 0, headroom);
1867 
1868 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1869 		ieee80211_free_txskb(&local->hw, skb);
1870 		return;
1871 	}
1872 
1873 	hdr = (struct ieee80211_hdr *) skb->data;
1874 	info->control.vif = &sdata->vif;
1875 
1876 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1877 		if (ieee80211_is_data(hdr->frame_control) &&
1878 		    is_unicast_ether_addr(hdr->addr1)) {
1879 			if (mesh_nexthop_resolve(sdata, skb))
1880 				return; /* skb queued: don't free */
1881 		} else {
1882 			ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
1883 		}
1884 	}
1885 
1886 	ieee80211_set_qos_hdr(sdata, skb);
1887 	ieee80211_tx(sdata, sta, skb, false);
1888 }
1889 
1890 static bool ieee80211_parse_tx_radiotap(struct ieee80211_local *local,
1891 					struct sk_buff *skb)
1892 {
1893 	struct ieee80211_radiotap_iterator iterator;
1894 	struct ieee80211_radiotap_header *rthdr =
1895 		(struct ieee80211_radiotap_header *) skb->data;
1896 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1897 	struct ieee80211_supported_band *sband =
1898 		local->hw.wiphy->bands[info->band];
1899 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1900 						   NULL);
1901 	u16 txflags;
1902 	u16 rate = 0;
1903 	bool rate_found = false;
1904 	u8 rate_retries = 0;
1905 	u16 rate_flags = 0;
1906 	u8 mcs_known, mcs_flags, mcs_bw;
1907 	u16 vht_known;
1908 	u8 vht_mcs = 0, vht_nss = 0;
1909 	int i;
1910 
1911 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1912 		       IEEE80211_TX_CTL_DONTFRAG;
1913 
1914 	/*
1915 	 * for every radiotap entry that is present
1916 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1917 	 * entries present, or -EINVAL on error)
1918 	 */
1919 
1920 	while (!ret) {
1921 		ret = ieee80211_radiotap_iterator_next(&iterator);
1922 
1923 		if (ret)
1924 			continue;
1925 
1926 		/* see if this argument is something we can use */
1927 		switch (iterator.this_arg_index) {
1928 		/*
1929 		 * You must take care when dereferencing iterator.this_arg
1930 		 * for multibyte types... the pointer is not aligned.  Use
1931 		 * get_unaligned((type *)iterator.this_arg) to dereference
1932 		 * iterator.this_arg for type "type" safely on all arches.
1933 		*/
1934 		case IEEE80211_RADIOTAP_FLAGS:
1935 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1936 				/*
1937 				 * this indicates that the skb we have been
1938 				 * handed has the 32-bit FCS CRC at the end...
1939 				 * we should react to that by snipping it off
1940 				 * because it will be recomputed and added
1941 				 * on transmission
1942 				 */
1943 				if (skb->len < (iterator._max_length + FCS_LEN))
1944 					return false;
1945 
1946 				skb_trim(skb, skb->len - FCS_LEN);
1947 			}
1948 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1949 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1950 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1951 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1952 			break;
1953 
1954 		case IEEE80211_RADIOTAP_TX_FLAGS:
1955 			txflags = get_unaligned_le16(iterator.this_arg);
1956 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1957 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1958 			break;
1959 
1960 		case IEEE80211_RADIOTAP_RATE:
1961 			rate = *iterator.this_arg;
1962 			rate_flags = 0;
1963 			rate_found = true;
1964 			break;
1965 
1966 		case IEEE80211_RADIOTAP_DATA_RETRIES:
1967 			rate_retries = *iterator.this_arg;
1968 			break;
1969 
1970 		case IEEE80211_RADIOTAP_MCS:
1971 			mcs_known = iterator.this_arg[0];
1972 			mcs_flags = iterator.this_arg[1];
1973 			if (!(mcs_known & IEEE80211_RADIOTAP_MCS_HAVE_MCS))
1974 				break;
1975 
1976 			rate_found = true;
1977 			rate = iterator.this_arg[2];
1978 			rate_flags = IEEE80211_TX_RC_MCS;
1979 
1980 			if (mcs_known & IEEE80211_RADIOTAP_MCS_HAVE_GI &&
1981 			    mcs_flags & IEEE80211_RADIOTAP_MCS_SGI)
1982 				rate_flags |= IEEE80211_TX_RC_SHORT_GI;
1983 
1984 			mcs_bw = mcs_flags & IEEE80211_RADIOTAP_MCS_BW_MASK;
1985 			if (mcs_known & IEEE80211_RADIOTAP_MCS_HAVE_BW &&
1986 			    mcs_bw == IEEE80211_RADIOTAP_MCS_BW_40)
1987 				rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
1988 			break;
1989 
1990 		case IEEE80211_RADIOTAP_VHT:
1991 			vht_known = get_unaligned_le16(iterator.this_arg);
1992 			rate_found = true;
1993 
1994 			rate_flags = IEEE80211_TX_RC_VHT_MCS;
1995 			if ((vht_known & IEEE80211_RADIOTAP_VHT_KNOWN_GI) &&
1996 			    (iterator.this_arg[2] &
1997 			     IEEE80211_RADIOTAP_VHT_FLAG_SGI))
1998 				rate_flags |= IEEE80211_TX_RC_SHORT_GI;
1999 			if (vht_known &
2000 			    IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH) {
2001 				if (iterator.this_arg[3] == 1)
2002 					rate_flags |=
2003 						IEEE80211_TX_RC_40_MHZ_WIDTH;
2004 				else if (iterator.this_arg[3] == 4)
2005 					rate_flags |=
2006 						IEEE80211_TX_RC_80_MHZ_WIDTH;
2007 				else if (iterator.this_arg[3] == 11)
2008 					rate_flags |=
2009 						IEEE80211_TX_RC_160_MHZ_WIDTH;
2010 			}
2011 
2012 			vht_mcs = iterator.this_arg[4] >> 4;
2013 			vht_nss = iterator.this_arg[4] & 0xF;
2014 			break;
2015 
2016 		/*
2017 		 * Please update the file
2018 		 * Documentation/networking/mac80211-injection.txt
2019 		 * when parsing new fields here.
2020 		 */
2021 
2022 		default:
2023 			break;
2024 		}
2025 	}
2026 
2027 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
2028 		return false;
2029 
2030 	if (rate_found) {
2031 		info->control.flags |= IEEE80211_TX_CTRL_RATE_INJECT;
2032 
2033 		for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
2034 			info->control.rates[i].idx = -1;
2035 			info->control.rates[i].flags = 0;
2036 			info->control.rates[i].count = 0;
2037 		}
2038 
2039 		if (rate_flags & IEEE80211_TX_RC_MCS) {
2040 			info->control.rates[0].idx = rate;
2041 		} else if (rate_flags & IEEE80211_TX_RC_VHT_MCS) {
2042 			ieee80211_rate_set_vht(info->control.rates, vht_mcs,
2043 					       vht_nss);
2044 		} else {
2045 			for (i = 0; i < sband->n_bitrates; i++) {
2046 				if (rate * 5 != sband->bitrates[i].bitrate)
2047 					continue;
2048 
2049 				info->control.rates[0].idx = i;
2050 				break;
2051 			}
2052 		}
2053 
2054 		if (info->control.rates[0].idx < 0)
2055 			info->control.flags &= ~IEEE80211_TX_CTRL_RATE_INJECT;
2056 
2057 		info->control.rates[0].flags = rate_flags;
2058 		info->control.rates[0].count = min_t(u8, rate_retries + 1,
2059 						     local->hw.max_rate_tries);
2060 	}
2061 
2062 	/*
2063 	 * remove the radiotap header
2064 	 * iterator->_max_length was sanity-checked against
2065 	 * skb->len by iterator init
2066 	 */
2067 	skb_pull(skb, iterator._max_length);
2068 
2069 	return true;
2070 }
2071 
2072 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
2073 					 struct net_device *dev)
2074 {
2075 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
2076 	struct ieee80211_chanctx_conf *chanctx_conf;
2077 	struct ieee80211_radiotap_header *prthdr =
2078 		(struct ieee80211_radiotap_header *)skb->data;
2079 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2080 	struct ieee80211_hdr *hdr;
2081 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
2082 	struct cfg80211_chan_def *chandef;
2083 	u16 len_rthdr;
2084 	int hdrlen;
2085 
2086 	/* check for not even having the fixed radiotap header part */
2087 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
2088 		goto fail; /* too short to be possibly valid */
2089 
2090 	/* is it a header version we can trust to find length from? */
2091 	if (unlikely(prthdr->it_version))
2092 		goto fail; /* only version 0 is supported */
2093 
2094 	/* then there must be a radiotap header with a length we can use */
2095 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
2096 
2097 	/* does the skb contain enough to deliver on the alleged length? */
2098 	if (unlikely(skb->len < len_rthdr))
2099 		goto fail; /* skb too short for claimed rt header extent */
2100 
2101 	/*
2102 	 * fix up the pointers accounting for the radiotap
2103 	 * header still being in there.  We are being given
2104 	 * a precooked IEEE80211 header so no need for
2105 	 * normal processing
2106 	 */
2107 	skb_set_mac_header(skb, len_rthdr);
2108 	/*
2109 	 * these are just fixed to the end of the rt area since we
2110 	 * don't have any better information and at this point, nobody cares
2111 	 */
2112 	skb_set_network_header(skb, len_rthdr);
2113 	skb_set_transport_header(skb, len_rthdr);
2114 
2115 	if (skb->len < len_rthdr + 2)
2116 		goto fail;
2117 
2118 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
2119 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
2120 
2121 	if (skb->len < len_rthdr + hdrlen)
2122 		goto fail;
2123 
2124 	/*
2125 	 * Initialize skb->protocol if the injected frame is a data frame
2126 	 * carrying a rfc1042 header
2127 	 */
2128 	if (ieee80211_is_data(hdr->frame_control) &&
2129 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
2130 		u8 *payload = (u8 *)hdr + hdrlen;
2131 
2132 		if (ether_addr_equal(payload, rfc1042_header))
2133 			skb->protocol = cpu_to_be16((payload[6] << 8) |
2134 						    payload[7]);
2135 	}
2136 
2137 	memset(info, 0, sizeof(*info));
2138 
2139 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
2140 		      IEEE80211_TX_CTL_INJECTED;
2141 
2142 	rcu_read_lock();
2143 
2144 	/*
2145 	 * We process outgoing injected frames that have a local address
2146 	 * we handle as though they are non-injected frames.
2147 	 * This code here isn't entirely correct, the local MAC address
2148 	 * isn't always enough to find the interface to use; for proper
2149 	 * VLAN/WDS support we will need a different mechanism (which
2150 	 * likely isn't going to be monitor interfaces).
2151 	 */
2152 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
2153 
2154 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
2155 		if (!ieee80211_sdata_running(tmp_sdata))
2156 			continue;
2157 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
2158 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
2159 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
2160 			continue;
2161 		if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
2162 			sdata = tmp_sdata;
2163 			break;
2164 		}
2165 	}
2166 
2167 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2168 	if (!chanctx_conf) {
2169 		tmp_sdata = rcu_dereference(local->monitor_sdata);
2170 		if (tmp_sdata)
2171 			chanctx_conf =
2172 				rcu_dereference(tmp_sdata->vif.chanctx_conf);
2173 	}
2174 
2175 	if (chanctx_conf)
2176 		chandef = &chanctx_conf->def;
2177 	else if (!local->use_chanctx)
2178 		chandef = &local->_oper_chandef;
2179 	else
2180 		goto fail_rcu;
2181 
2182 	/*
2183 	 * Frame injection is not allowed if beaconing is not allowed
2184 	 * or if we need radar detection. Beaconing is usually not allowed when
2185 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
2186 	 * Passive scan is also used in world regulatory domains where
2187 	 * your country is not known and as such it should be treated as
2188 	 * NO TX unless the channel is explicitly allowed in which case
2189 	 * your current regulatory domain would not have the passive scan
2190 	 * flag.
2191 	 *
2192 	 * Since AP mode uses monitor interfaces to inject/TX management
2193 	 * frames we can make AP mode the exception to this rule once it
2194 	 * supports radar detection as its implementation can deal with
2195 	 * radar detection by itself. We can do that later by adding a
2196 	 * monitor flag interfaces used for AP support.
2197 	 */
2198 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, chandef,
2199 				     sdata->vif.type))
2200 		goto fail_rcu;
2201 
2202 	info->band = chandef->chan->band;
2203 
2204 	/* process and remove the injection radiotap header */
2205 	if (!ieee80211_parse_tx_radiotap(local, skb))
2206 		goto fail_rcu;
2207 
2208 	ieee80211_xmit(sdata, NULL, skb);
2209 	rcu_read_unlock();
2210 
2211 	return NETDEV_TX_OK;
2212 
2213 fail_rcu:
2214 	rcu_read_unlock();
2215 fail:
2216 	dev_kfree_skb(skb);
2217 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
2218 }
2219 
2220 static inline bool ieee80211_is_tdls_setup(struct sk_buff *skb)
2221 {
2222 	u16 ethertype = (skb->data[12] << 8) | skb->data[13];
2223 
2224 	return ethertype == ETH_P_TDLS &&
2225 	       skb->len > 14 &&
2226 	       skb->data[14] == WLAN_TDLS_SNAP_RFTYPE;
2227 }
2228 
2229 static int ieee80211_lookup_ra_sta(struct ieee80211_sub_if_data *sdata,
2230 				   struct sk_buff *skb,
2231 				   struct sta_info **sta_out)
2232 {
2233 	struct sta_info *sta;
2234 
2235 	switch (sdata->vif.type) {
2236 	case NL80211_IFTYPE_AP_VLAN:
2237 		sta = rcu_dereference(sdata->u.vlan.sta);
2238 		if (sta) {
2239 			*sta_out = sta;
2240 			return 0;
2241 		} else if (sdata->wdev.use_4addr) {
2242 			return -ENOLINK;
2243 		}
2244 		/* fall through */
2245 	case NL80211_IFTYPE_AP:
2246 	case NL80211_IFTYPE_OCB:
2247 	case NL80211_IFTYPE_ADHOC:
2248 		if (is_multicast_ether_addr(skb->data)) {
2249 			*sta_out = ERR_PTR(-ENOENT);
2250 			return 0;
2251 		}
2252 		sta = sta_info_get_bss(sdata, skb->data);
2253 		break;
2254 	case NL80211_IFTYPE_WDS:
2255 		sta = sta_info_get(sdata, sdata->u.wds.remote_addr);
2256 		break;
2257 #ifdef CONFIG_MAC80211_MESH
2258 	case NL80211_IFTYPE_MESH_POINT:
2259 		/* determined much later */
2260 		*sta_out = NULL;
2261 		return 0;
2262 #endif
2263 	case NL80211_IFTYPE_STATION:
2264 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
2265 			sta = sta_info_get(sdata, skb->data);
2266 			if (sta) {
2267 				bool tdls_peer, tdls_auth;
2268 
2269 				tdls_peer = test_sta_flag(sta,
2270 							  WLAN_STA_TDLS_PEER);
2271 				tdls_auth = test_sta_flag(sta,
2272 						WLAN_STA_TDLS_PEER_AUTH);
2273 
2274 				if (tdls_peer && tdls_auth) {
2275 					*sta_out = sta;
2276 					return 0;
2277 				}
2278 
2279 				/*
2280 				 * TDLS link during setup - throw out frames to
2281 				 * peer. Allow TDLS-setup frames to unauthorized
2282 				 * peers for the special case of a link teardown
2283 				 * after a TDLS sta is removed due to being
2284 				 * unreachable.
2285 				 */
2286 				if (tdls_peer && !tdls_auth &&
2287 				    !ieee80211_is_tdls_setup(skb))
2288 					return -EINVAL;
2289 			}
2290 
2291 		}
2292 
2293 		sta = sta_info_get(sdata, sdata->u.mgd.bssid);
2294 		if (!sta)
2295 			return -ENOLINK;
2296 		break;
2297 	default:
2298 		return -EINVAL;
2299 	}
2300 
2301 	*sta_out = sta ?: ERR_PTR(-ENOENT);
2302 	return 0;
2303 }
2304 
2305 /**
2306  * ieee80211_build_hdr - build 802.11 header in the given frame
2307  * @sdata: virtual interface to build the header for
2308  * @skb: the skb to build the header in
2309  * @info_flags: skb flags to set
2310  *
2311  * This function takes the skb with 802.3 header and reformats the header to
2312  * the appropriate IEEE 802.11 header based on which interface the packet is
2313  * being transmitted on.
2314  *
2315  * Note that this function also takes care of the TX status request and
2316  * potential unsharing of the SKB - this needs to be interleaved with the
2317  * header building.
2318  *
2319  * The function requires the read-side RCU lock held
2320  *
2321  * Returns: the (possibly reallocated) skb or an ERR_PTR() code
2322  */
2323 static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
2324 					   struct sk_buff *skb, u32 info_flags,
2325 					   struct sta_info *sta)
2326 {
2327 	struct ieee80211_local *local = sdata->local;
2328 	struct ieee80211_tx_info *info;
2329 	int head_need;
2330 	u16 ethertype, hdrlen,  meshhdrlen = 0;
2331 	__le16 fc;
2332 	struct ieee80211_hdr hdr;
2333 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
2334 	struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
2335 	const u8 *encaps_data;
2336 	int encaps_len, skip_header_bytes;
2337 	bool wme_sta = false, authorized = false;
2338 	bool tdls_peer;
2339 	bool multicast;
2340 	u16 info_id = 0;
2341 	struct ieee80211_chanctx_conf *chanctx_conf;
2342 	struct ieee80211_sub_if_data *ap_sdata;
2343 	enum nl80211_band band;
2344 	int ret;
2345 
2346 	if (IS_ERR(sta))
2347 		sta = NULL;
2348 
2349 	/* convert Ethernet header to proper 802.11 header (based on
2350 	 * operation mode) */
2351 	ethertype = (skb->data[12] << 8) | skb->data[13];
2352 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
2353 
2354 	switch (sdata->vif.type) {
2355 	case NL80211_IFTYPE_AP_VLAN:
2356 		if (sdata->wdev.use_4addr) {
2357 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
2358 			/* RA TA DA SA */
2359 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
2360 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2361 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2362 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2363 			hdrlen = 30;
2364 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
2365 			wme_sta = sta->sta.wme;
2366 		}
2367 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2368 					u.ap);
2369 		chanctx_conf = rcu_dereference(ap_sdata->vif.chanctx_conf);
2370 		if (!chanctx_conf) {
2371 			ret = -ENOTCONN;
2372 			goto free;
2373 		}
2374 		band = chanctx_conf->def.chan->band;
2375 		if (sdata->wdev.use_4addr)
2376 			break;
2377 		/* fall through */
2378 	case NL80211_IFTYPE_AP:
2379 		if (sdata->vif.type == NL80211_IFTYPE_AP)
2380 			chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2381 		if (!chanctx_conf) {
2382 			ret = -ENOTCONN;
2383 			goto free;
2384 		}
2385 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
2386 		/* DA BSSID SA */
2387 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2388 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2389 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
2390 		hdrlen = 24;
2391 		band = chanctx_conf->def.chan->band;
2392 		break;
2393 	case NL80211_IFTYPE_WDS:
2394 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
2395 		/* RA TA DA SA */
2396 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
2397 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2398 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
2399 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2400 		hdrlen = 30;
2401 		/*
2402 		 * This is the exception! WDS style interfaces are prohibited
2403 		 * when channel contexts are in used so this must be valid
2404 		 */
2405 		band = local->hw.conf.chandef.chan->band;
2406 		break;
2407 #ifdef CONFIG_MAC80211_MESH
2408 	case NL80211_IFTYPE_MESH_POINT:
2409 		if (!is_multicast_ether_addr(skb->data)) {
2410 			struct sta_info *next_hop;
2411 			bool mpp_lookup = true;
2412 
2413 			mpath = mesh_path_lookup(sdata, skb->data);
2414 			if (mpath) {
2415 				mpp_lookup = false;
2416 				next_hop = rcu_dereference(mpath->next_hop);
2417 				if (!next_hop ||
2418 				    !(mpath->flags & (MESH_PATH_ACTIVE |
2419 						      MESH_PATH_RESOLVING)))
2420 					mpp_lookup = true;
2421 			}
2422 
2423 			if (mpp_lookup) {
2424 				mppath = mpp_path_lookup(sdata, skb->data);
2425 				if (mppath)
2426 					mppath->exp_time = jiffies;
2427 			}
2428 
2429 			if (mppath && mpath)
2430 				mesh_path_del(sdata, mpath->dst);
2431 		}
2432 
2433 		/*
2434 		 * Use address extension if it is a packet from
2435 		 * another interface or if we know the destination
2436 		 * is being proxied by a portal (i.e. portal address
2437 		 * differs from proxied address)
2438 		 */
2439 		if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
2440 		    !(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
2441 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
2442 					skb->data, skb->data + ETH_ALEN);
2443 			meshhdrlen = ieee80211_new_mesh_header(sdata, &mesh_hdr,
2444 							       NULL, NULL);
2445 		} else {
2446 			/* DS -> MBSS (802.11-2012 13.11.3.3).
2447 			 * For unicast with unknown forwarding information,
2448 			 * destination might be in the MBSS or if that fails
2449 			 * forwarded to another mesh gate. In either case
2450 			 * resolution will be handled in ieee80211_xmit(), so
2451 			 * leave the original DA. This also works for mcast */
2452 			const u8 *mesh_da = skb->data;
2453 
2454 			if (mppath)
2455 				mesh_da = mppath->mpp;
2456 			else if (mpath)
2457 				mesh_da = mpath->dst;
2458 
2459 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
2460 					mesh_da, sdata->vif.addr);
2461 			if (is_multicast_ether_addr(mesh_da))
2462 				/* DA TA mSA AE:SA */
2463 				meshhdrlen = ieee80211_new_mesh_header(
2464 						sdata, &mesh_hdr,
2465 						skb->data + ETH_ALEN, NULL);
2466 			else
2467 				/* RA TA mDA mSA AE:DA SA */
2468 				meshhdrlen = ieee80211_new_mesh_header(
2469 						sdata, &mesh_hdr, skb->data,
2470 						skb->data + ETH_ALEN);
2471 
2472 		}
2473 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2474 		if (!chanctx_conf) {
2475 			ret = -ENOTCONN;
2476 			goto free;
2477 		}
2478 		band = chanctx_conf->def.chan->band;
2479 		break;
2480 #endif
2481 	case NL80211_IFTYPE_STATION:
2482 		/* we already did checks when looking up the RA STA */
2483 		tdls_peer = test_sta_flag(sta, WLAN_STA_TDLS_PEER);
2484 
2485 		if (tdls_peer) {
2486 			/* DA SA BSSID */
2487 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
2488 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2489 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
2490 			hdrlen = 24;
2491 		}  else if (sdata->u.mgd.use_4addr &&
2492 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
2493 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2494 					  IEEE80211_FCTL_TODS);
2495 			/* RA TA DA SA */
2496 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
2497 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2498 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2499 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2500 			hdrlen = 30;
2501 		} else {
2502 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
2503 			/* BSSID SA DA */
2504 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
2505 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2506 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2507 			hdrlen = 24;
2508 		}
2509 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2510 		if (!chanctx_conf) {
2511 			ret = -ENOTCONN;
2512 			goto free;
2513 		}
2514 		band = chanctx_conf->def.chan->band;
2515 		break;
2516 	case NL80211_IFTYPE_OCB:
2517 		/* DA SA BSSID */
2518 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2519 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2520 		eth_broadcast_addr(hdr.addr3);
2521 		hdrlen = 24;
2522 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2523 		if (!chanctx_conf) {
2524 			ret = -ENOTCONN;
2525 			goto free;
2526 		}
2527 		band = chanctx_conf->def.chan->band;
2528 		break;
2529 	case NL80211_IFTYPE_ADHOC:
2530 		/* DA SA BSSID */
2531 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2532 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2533 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
2534 		hdrlen = 24;
2535 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2536 		if (!chanctx_conf) {
2537 			ret = -ENOTCONN;
2538 			goto free;
2539 		}
2540 		band = chanctx_conf->def.chan->band;
2541 		break;
2542 	default:
2543 		ret = -EINVAL;
2544 		goto free;
2545 	}
2546 
2547 	multicast = is_multicast_ether_addr(hdr.addr1);
2548 
2549 	/* sta is always NULL for mesh */
2550 	if (sta) {
2551 		authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
2552 		wme_sta = sta->sta.wme;
2553 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2554 		/* For mesh, the use of the QoS header is mandatory */
2555 		wme_sta = true;
2556 	}
2557 
2558 	/* receiver does QoS (which also means we do) use it */
2559 	if (wme_sta) {
2560 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2561 		hdrlen += 2;
2562 	}
2563 
2564 	/*
2565 	 * Drop unicast frames to unauthorised stations unless they are
2566 	 * EAPOL frames from the local station.
2567 	 */
2568 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
2569 		     (sdata->vif.type != NL80211_IFTYPE_OCB) &&
2570 		     !multicast && !authorized &&
2571 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
2572 		      !ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
2573 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
2574 		net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
2575 				    sdata->name, hdr.addr1);
2576 #endif
2577 
2578 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
2579 
2580 		ret = -EPERM;
2581 		goto free;
2582 	}
2583 
2584 	if (unlikely(!multicast && skb->sk &&
2585 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
2586 		struct sk_buff *ack_skb = skb_clone_sk(skb);
2587 
2588 		if (ack_skb) {
2589 			unsigned long flags;
2590 			int id;
2591 
2592 			spin_lock_irqsave(&local->ack_status_lock, flags);
2593 			id = idr_alloc(&local->ack_status_frames, ack_skb,
2594 				       1, 0x10000, GFP_ATOMIC);
2595 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
2596 
2597 			if (id >= 0) {
2598 				info_id = id;
2599 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
2600 			} else {
2601 				kfree_skb(ack_skb);
2602 			}
2603 		}
2604 	}
2605 
2606 	/*
2607 	 * If the skb is shared we need to obtain our own copy.
2608 	 */
2609 	if (skb_shared(skb)) {
2610 		struct sk_buff *tmp_skb = skb;
2611 
2612 		/* can't happen -- skb is a clone if info_id != 0 */
2613 		WARN_ON(info_id);
2614 
2615 		skb = skb_clone(skb, GFP_ATOMIC);
2616 		kfree_skb(tmp_skb);
2617 
2618 		if (!skb) {
2619 			ret = -ENOMEM;
2620 			goto free;
2621 		}
2622 	}
2623 
2624 	hdr.frame_control = fc;
2625 	hdr.duration_id = 0;
2626 	hdr.seq_ctrl = 0;
2627 
2628 	skip_header_bytes = ETH_HLEN;
2629 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2630 		encaps_data = bridge_tunnel_header;
2631 		encaps_len = sizeof(bridge_tunnel_header);
2632 		skip_header_bytes -= 2;
2633 	} else if (ethertype >= ETH_P_802_3_MIN) {
2634 		encaps_data = rfc1042_header;
2635 		encaps_len = sizeof(rfc1042_header);
2636 		skip_header_bytes -= 2;
2637 	} else {
2638 		encaps_data = NULL;
2639 		encaps_len = 0;
2640 	}
2641 
2642 	skb_pull(skb, skip_header_bytes);
2643 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2644 
2645 	/*
2646 	 * So we need to modify the skb header and hence need a copy of
2647 	 * that. The head_need variable above doesn't, so far, include
2648 	 * the needed header space that we don't need right away. If we
2649 	 * can, then we don't reallocate right now but only after the
2650 	 * frame arrives at the master device (if it does...)
2651 	 *
2652 	 * If we cannot, however, then we will reallocate to include all
2653 	 * the ever needed space. Also, if we need to reallocate it anyway,
2654 	 * make it big enough for everything we may ever need.
2655 	 */
2656 
2657 	if (head_need > 0 || skb_cloned(skb)) {
2658 		head_need += sdata->encrypt_headroom;
2659 		head_need += local->tx_headroom;
2660 		head_need = max_t(int, 0, head_need);
2661 		if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
2662 			ieee80211_free_txskb(&local->hw, skb);
2663 			skb = NULL;
2664 			return ERR_PTR(-ENOMEM);
2665 		}
2666 	}
2667 
2668 	if (encaps_data)
2669 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2670 
2671 #ifdef CONFIG_MAC80211_MESH
2672 	if (meshhdrlen > 0)
2673 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2674 #endif
2675 
2676 	if (ieee80211_is_data_qos(fc)) {
2677 		__le16 *qos_control;
2678 
2679 		qos_control = (__le16 *) skb_push(skb, 2);
2680 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2681 		/*
2682 		 * Maybe we could actually set some fields here, for now just
2683 		 * initialise to zero to indicate no special operation.
2684 		 */
2685 		*qos_control = 0;
2686 	} else
2687 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2688 
2689 	skb_reset_mac_header(skb);
2690 
2691 	info = IEEE80211_SKB_CB(skb);
2692 	memset(info, 0, sizeof(*info));
2693 
2694 	info->flags = info_flags;
2695 	info->ack_frame_id = info_id;
2696 	info->band = band;
2697 
2698 	return skb;
2699  free:
2700 	kfree_skb(skb);
2701 	return ERR_PTR(ret);
2702 }
2703 
2704 /*
2705  * fast-xmit overview
2706  *
2707  * The core idea of this fast-xmit is to remove per-packet checks by checking
2708  * them out of band. ieee80211_check_fast_xmit() implements the out-of-band
2709  * checks that are needed to get the sta->fast_tx pointer assigned, after which
2710  * much less work can be done per packet. For example, fragmentation must be
2711  * disabled or the fast_tx pointer will not be set. All the conditions are seen
2712  * in the code here.
2713  *
2714  * Once assigned, the fast_tx data structure also caches the per-packet 802.11
2715  * header and other data to aid packet processing in ieee80211_xmit_fast().
2716  *
2717  * The most difficult part of this is that when any of these assumptions
2718  * change, an external trigger (i.e. a call to ieee80211_clear_fast_xmit(),
2719  * ieee80211_check_fast_xmit() or friends) is required to reset the data,
2720  * since the per-packet code no longer checks the conditions. This is reflected
2721  * by the calls to these functions throughout the rest of the code, and must be
2722  * maintained if any of the TX path checks change.
2723  */
2724 
2725 void ieee80211_check_fast_xmit(struct sta_info *sta)
2726 {
2727 	struct ieee80211_fast_tx build = {}, *fast_tx = NULL, *old;
2728 	struct ieee80211_local *local = sta->local;
2729 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2730 	struct ieee80211_hdr *hdr = (void *)build.hdr;
2731 	struct ieee80211_chanctx_conf *chanctx_conf;
2732 	__le16 fc;
2733 
2734 	if (!ieee80211_hw_check(&local->hw, SUPPORT_FAST_XMIT))
2735 		return;
2736 
2737 	/* Locking here protects both the pointer itself, and against concurrent
2738 	 * invocations winning data access races to, e.g., the key pointer that
2739 	 * is used.
2740 	 * Without it, the invocation of this function right after the key
2741 	 * pointer changes wouldn't be sufficient, as another CPU could access
2742 	 * the pointer, then stall, and then do the cache update after the CPU
2743 	 * that invalidated the key.
2744 	 * With the locking, such scenarios cannot happen as the check for the
2745 	 * key and the fast-tx assignment are done atomically, so the CPU that
2746 	 * modifies the key will either wait or other one will see the key
2747 	 * cleared/changed already.
2748 	 */
2749 	spin_lock_bh(&sta->lock);
2750 	if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
2751 	    !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
2752 	    sdata->vif.type == NL80211_IFTYPE_STATION)
2753 		goto out;
2754 
2755 	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
2756 		goto out;
2757 
2758 	if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
2759 	    test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
2760 	    test_sta_flag(sta, WLAN_STA_PS_DELIVER) ||
2761 	    test_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT))
2762 		goto out;
2763 
2764 	if (sdata->noack_map)
2765 		goto out;
2766 
2767 	/* fast-xmit doesn't handle fragmentation at all */
2768 	if (local->hw.wiphy->frag_threshold != (u32)-1 &&
2769 	    !local->ops->set_frag_threshold)
2770 		goto out;
2771 
2772 	rcu_read_lock();
2773 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2774 	if (!chanctx_conf) {
2775 		rcu_read_unlock();
2776 		goto out;
2777 	}
2778 	build.band = chanctx_conf->def.chan->band;
2779 	rcu_read_unlock();
2780 
2781 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
2782 
2783 	switch (sdata->vif.type) {
2784 	case NL80211_IFTYPE_ADHOC:
2785 		/* DA SA BSSID */
2786 		build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2787 		build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2788 		memcpy(hdr->addr3, sdata->u.ibss.bssid, ETH_ALEN);
2789 		build.hdr_len = 24;
2790 		break;
2791 	case NL80211_IFTYPE_STATION:
2792 		if (test_sta_flag(sta, WLAN_STA_TDLS_PEER)) {
2793 			/* DA SA BSSID */
2794 			build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2795 			build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2796 			memcpy(hdr->addr3, sdata->u.mgd.bssid, ETH_ALEN);
2797 			build.hdr_len = 24;
2798 			break;
2799 		}
2800 
2801 		if (sdata->u.mgd.use_4addr) {
2802 			/* non-regular ethertype cannot use the fastpath */
2803 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2804 					  IEEE80211_FCTL_TODS);
2805 			/* RA TA DA SA */
2806 			memcpy(hdr->addr1, sdata->u.mgd.bssid, ETH_ALEN);
2807 			memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2808 			build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2809 			build.sa_offs = offsetof(struct ieee80211_hdr, addr4);
2810 			build.hdr_len = 30;
2811 			break;
2812 		}
2813 		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
2814 		/* BSSID SA DA */
2815 		memcpy(hdr->addr1, sdata->u.mgd.bssid, ETH_ALEN);
2816 		build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2817 		build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2818 		build.hdr_len = 24;
2819 		break;
2820 	case NL80211_IFTYPE_AP_VLAN:
2821 		if (sdata->wdev.use_4addr) {
2822 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2823 					  IEEE80211_FCTL_TODS);
2824 			/* RA TA DA SA */
2825 			memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
2826 			memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2827 			build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2828 			build.sa_offs = offsetof(struct ieee80211_hdr, addr4);
2829 			build.hdr_len = 30;
2830 			break;
2831 		}
2832 		/* fall through */
2833 	case NL80211_IFTYPE_AP:
2834 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
2835 		/* DA BSSID SA */
2836 		build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2837 		memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2838 		build.sa_offs = offsetof(struct ieee80211_hdr, addr3);
2839 		build.hdr_len = 24;
2840 		break;
2841 	default:
2842 		/* not handled on fast-xmit */
2843 		goto out;
2844 	}
2845 
2846 	if (sta->sta.wme) {
2847 		build.hdr_len += 2;
2848 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2849 	}
2850 
2851 	/* We store the key here so there's no point in using rcu_dereference()
2852 	 * but that's fine because the code that changes the pointers will call
2853 	 * this function after doing so. For a single CPU that would be enough,
2854 	 * for multiple see the comment above.
2855 	 */
2856 	build.key = rcu_access_pointer(sta->ptk[sta->ptk_idx]);
2857 	if (!build.key)
2858 		build.key = rcu_access_pointer(sdata->default_unicast_key);
2859 	if (build.key) {
2860 		bool gen_iv, iv_spc, mmic;
2861 
2862 		gen_iv = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
2863 		iv_spc = build.key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
2864 		mmic = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC;
2865 
2866 		/* don't handle software crypto */
2867 		if (!(build.key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
2868 			goto out;
2869 
2870 		switch (build.key->conf.cipher) {
2871 		case WLAN_CIPHER_SUITE_CCMP:
2872 		case WLAN_CIPHER_SUITE_CCMP_256:
2873 			/* add fixed key ID */
2874 			if (gen_iv) {
2875 				(build.hdr + build.hdr_len)[3] =
2876 					0x20 | (build.key->conf.keyidx << 6);
2877 				build.pn_offs = build.hdr_len;
2878 			}
2879 			if (gen_iv || iv_spc)
2880 				build.hdr_len += IEEE80211_CCMP_HDR_LEN;
2881 			break;
2882 		case WLAN_CIPHER_SUITE_GCMP:
2883 		case WLAN_CIPHER_SUITE_GCMP_256:
2884 			/* add fixed key ID */
2885 			if (gen_iv) {
2886 				(build.hdr + build.hdr_len)[3] =
2887 					0x20 | (build.key->conf.keyidx << 6);
2888 				build.pn_offs = build.hdr_len;
2889 			}
2890 			if (gen_iv || iv_spc)
2891 				build.hdr_len += IEEE80211_GCMP_HDR_LEN;
2892 			break;
2893 		case WLAN_CIPHER_SUITE_TKIP:
2894 			/* cannot handle MMIC or IV generation in xmit-fast */
2895 			if (mmic || gen_iv)
2896 				goto out;
2897 			if (iv_spc)
2898 				build.hdr_len += IEEE80211_TKIP_IV_LEN;
2899 			break;
2900 		case WLAN_CIPHER_SUITE_WEP40:
2901 		case WLAN_CIPHER_SUITE_WEP104:
2902 			/* cannot handle IV generation in fast-xmit */
2903 			if (gen_iv)
2904 				goto out;
2905 			if (iv_spc)
2906 				build.hdr_len += IEEE80211_WEP_IV_LEN;
2907 			break;
2908 		case WLAN_CIPHER_SUITE_AES_CMAC:
2909 		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
2910 		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
2911 		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
2912 			WARN(1,
2913 			     "management cipher suite 0x%x enabled for data\n",
2914 			     build.key->conf.cipher);
2915 			goto out;
2916 		default:
2917 			/* we don't know how to generate IVs for this at all */
2918 			if (WARN_ON(gen_iv))
2919 				goto out;
2920 			/* pure hardware keys are OK, of course */
2921 			if (!(build.key->flags & KEY_FLAG_CIPHER_SCHEME))
2922 				break;
2923 			/* cipher scheme might require space allocation */
2924 			if (iv_spc &&
2925 			    build.key->conf.iv_len > IEEE80211_FAST_XMIT_MAX_IV)
2926 				goto out;
2927 			if (iv_spc)
2928 				build.hdr_len += build.key->conf.iv_len;
2929 		}
2930 
2931 		fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
2932 	}
2933 
2934 	hdr->frame_control = fc;
2935 
2936 	memcpy(build.hdr + build.hdr_len,
2937 	       rfc1042_header,  sizeof(rfc1042_header));
2938 	build.hdr_len += sizeof(rfc1042_header);
2939 
2940 	fast_tx = kmemdup(&build, sizeof(build), GFP_ATOMIC);
2941 	/* if the kmemdup fails, continue w/o fast_tx */
2942 	if (!fast_tx)
2943 		goto out;
2944 
2945  out:
2946 	/* we might have raced against another call to this function */
2947 	old = rcu_dereference_protected(sta->fast_tx,
2948 					lockdep_is_held(&sta->lock));
2949 	rcu_assign_pointer(sta->fast_tx, fast_tx);
2950 	if (old)
2951 		kfree_rcu(old, rcu_head);
2952 	spin_unlock_bh(&sta->lock);
2953 }
2954 
2955 void ieee80211_check_fast_xmit_all(struct ieee80211_local *local)
2956 {
2957 	struct sta_info *sta;
2958 
2959 	rcu_read_lock();
2960 	list_for_each_entry_rcu(sta, &local->sta_list, list)
2961 		ieee80211_check_fast_xmit(sta);
2962 	rcu_read_unlock();
2963 }
2964 
2965 void ieee80211_check_fast_xmit_iface(struct ieee80211_sub_if_data *sdata)
2966 {
2967 	struct ieee80211_local *local = sdata->local;
2968 	struct sta_info *sta;
2969 
2970 	rcu_read_lock();
2971 
2972 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
2973 		if (sdata != sta->sdata &&
2974 		    (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
2975 			continue;
2976 		ieee80211_check_fast_xmit(sta);
2977 	}
2978 
2979 	rcu_read_unlock();
2980 }
2981 
2982 void ieee80211_clear_fast_xmit(struct sta_info *sta)
2983 {
2984 	struct ieee80211_fast_tx *fast_tx;
2985 
2986 	spin_lock_bh(&sta->lock);
2987 	fast_tx = rcu_dereference_protected(sta->fast_tx,
2988 					    lockdep_is_held(&sta->lock));
2989 	RCU_INIT_POINTER(sta->fast_tx, NULL);
2990 	spin_unlock_bh(&sta->lock);
2991 
2992 	if (fast_tx)
2993 		kfree_rcu(fast_tx, rcu_head);
2994 }
2995 
2996 static bool ieee80211_amsdu_realloc_pad(struct ieee80211_local *local,
2997 					struct sk_buff *skb, int headroom,
2998 					int *subframe_len)
2999 {
3000 	int amsdu_len = *subframe_len + sizeof(struct ethhdr);
3001 	int padding = (4 - amsdu_len) & 3;
3002 
3003 	if (skb_headroom(skb) < headroom || skb_tailroom(skb) < padding) {
3004 		I802_DEBUG_INC(local->tx_expand_skb_head);
3005 
3006 		if (pskb_expand_head(skb, headroom, padding, GFP_ATOMIC)) {
3007 			wiphy_debug(local->hw.wiphy,
3008 				    "failed to reallocate TX buffer\n");
3009 			return false;
3010 		}
3011 	}
3012 
3013 	if (padding) {
3014 		*subframe_len += padding;
3015 		memset(skb_put(skb, padding), 0, padding);
3016 	}
3017 
3018 	return true;
3019 }
3020 
3021 static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata,
3022 					 struct ieee80211_fast_tx *fast_tx,
3023 					 struct sk_buff *skb)
3024 {
3025 	struct ieee80211_local *local = sdata->local;
3026 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3027 	struct ieee80211_hdr *hdr;
3028 	struct ethhdr amsdu_hdr;
3029 	int hdr_len = fast_tx->hdr_len - sizeof(rfc1042_header);
3030 	int subframe_len = skb->len - hdr_len;
3031 	void *data;
3032 	u8 *qc;
3033 
3034 	if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
3035 		return false;
3036 
3037 	if (info->control.flags & IEEE80211_TX_CTRL_AMSDU)
3038 		return true;
3039 
3040 	if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(amsdu_hdr),
3041 					 &subframe_len))
3042 		return false;
3043 
3044 	amsdu_hdr.h_proto = cpu_to_be16(subframe_len);
3045 	memcpy(amsdu_hdr.h_source, skb->data + fast_tx->sa_offs, ETH_ALEN);
3046 	memcpy(amsdu_hdr.h_dest, skb->data + fast_tx->da_offs, ETH_ALEN);
3047 
3048 	data = skb_push(skb, sizeof(amsdu_hdr));
3049 	memmove(data, data + sizeof(amsdu_hdr), hdr_len);
3050 	memcpy(data + hdr_len, &amsdu_hdr, sizeof(amsdu_hdr));
3051 
3052 	hdr = data;
3053 	qc = ieee80211_get_qos_ctl(hdr);
3054 	*qc |= IEEE80211_QOS_CTL_A_MSDU_PRESENT;
3055 
3056 	info->control.flags |= IEEE80211_TX_CTRL_AMSDU;
3057 
3058 	return true;
3059 }
3060 
3061 static bool ieee80211_amsdu_aggregate(struct ieee80211_sub_if_data *sdata,
3062 				      struct sta_info *sta,
3063 				      struct ieee80211_fast_tx *fast_tx,
3064 				      struct sk_buff *skb)
3065 {
3066 	struct ieee80211_local *local = sdata->local;
3067 	struct fq *fq = &local->fq;
3068 	struct fq_tin *tin;
3069 	struct fq_flow *flow;
3070 	u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
3071 	struct ieee80211_txq *txq = sta->sta.txq[tid];
3072 	struct txq_info *txqi;
3073 	struct sk_buff **frag_tail, *head;
3074 	int subframe_len = skb->len - ETH_ALEN;
3075 	u8 max_subframes = sta->sta.max_amsdu_subframes;
3076 	int max_frags = local->hw.max_tx_fragments;
3077 	int max_amsdu_len = sta->sta.max_amsdu_len;
3078 	__be16 len;
3079 	void *data;
3080 	bool ret = false;
3081 	unsigned int orig_len;
3082 	int n = 1, nfrags;
3083 
3084 	if (!ieee80211_hw_check(&local->hw, TX_AMSDU))
3085 		return false;
3086 
3087 	if (!txq)
3088 		return false;
3089 
3090 	txqi = to_txq_info(txq);
3091 	if (test_bit(IEEE80211_TXQ_NO_AMSDU, &txqi->flags))
3092 		return false;
3093 
3094 	if (sta->sta.max_rc_amsdu_len)
3095 		max_amsdu_len = min_t(int, max_amsdu_len,
3096 				      sta->sta.max_rc_amsdu_len);
3097 
3098 	spin_lock_bh(&fq->lock);
3099 
3100 	/* TODO: Ideally aggregation should be done on dequeue to remain
3101 	 * responsive to environment changes.
3102 	 */
3103 
3104 	tin = &txqi->tin;
3105 	flow = fq_flow_classify(fq, tin, skb, fq_flow_get_default_func);
3106 	head = skb_peek_tail(&flow->queue);
3107 	if (!head)
3108 		goto out;
3109 
3110 	orig_len = head->len;
3111 
3112 	if (skb->len + head->len > max_amsdu_len)
3113 		goto out;
3114 
3115 	if (!ieee80211_amsdu_prepare_head(sdata, fast_tx, head))
3116 		goto out;
3117 
3118 	nfrags = 1 + skb_shinfo(skb)->nr_frags;
3119 	nfrags += 1 + skb_shinfo(head)->nr_frags;
3120 	frag_tail = &skb_shinfo(head)->frag_list;
3121 	while (*frag_tail) {
3122 		nfrags += 1 + skb_shinfo(*frag_tail)->nr_frags;
3123 		frag_tail = &(*frag_tail)->next;
3124 		n++;
3125 	}
3126 
3127 	if (max_subframes && n > max_subframes)
3128 		goto out;
3129 
3130 	if (max_frags && nfrags > max_frags)
3131 		goto out;
3132 
3133 	if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(rfc1042_header) + 2,
3134 					 &subframe_len))
3135 		goto out;
3136 
3137 	ret = true;
3138 	data = skb_push(skb, ETH_ALEN + 2);
3139 	memmove(data, data + ETH_ALEN + 2, 2 * ETH_ALEN);
3140 
3141 	data += 2 * ETH_ALEN;
3142 	len = cpu_to_be16(subframe_len);
3143 	memcpy(data, &len, 2);
3144 	memcpy(data + 2, rfc1042_header, sizeof(rfc1042_header));
3145 
3146 	head->len += skb->len;
3147 	head->data_len += skb->len;
3148 	*frag_tail = skb;
3149 
3150 	flow->backlog += head->len - orig_len;
3151 	tin->backlog_bytes += head->len - orig_len;
3152 
3153 	fq_recalc_backlog(fq, tin, flow);
3154 
3155 out:
3156 	spin_unlock_bh(&fq->lock);
3157 
3158 	return ret;
3159 }
3160 
3161 static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata,
3162 				struct net_device *dev, struct sta_info *sta,
3163 				struct ieee80211_fast_tx *fast_tx,
3164 				struct sk_buff *skb)
3165 {
3166 	struct ieee80211_local *local = sdata->local;
3167 	u16 ethertype = (skb->data[12] << 8) | skb->data[13];
3168 	int extra_head = fast_tx->hdr_len - (ETH_HLEN - 2);
3169 	int hw_headroom = sdata->local->hw.extra_tx_headroom;
3170 	struct ethhdr eth;
3171 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3172 	struct ieee80211_hdr *hdr = (void *)fast_tx->hdr;
3173 	struct ieee80211_tx_data tx;
3174 	ieee80211_tx_result r;
3175 	struct tid_ampdu_tx *tid_tx = NULL;
3176 	u8 tid = IEEE80211_NUM_TIDS;
3177 
3178 	/* control port protocol needs a lot of special handling */
3179 	if (cpu_to_be16(ethertype) == sdata->control_port_protocol)
3180 		return false;
3181 
3182 	/* only RFC 1042 SNAP */
3183 	if (ethertype < ETH_P_802_3_MIN)
3184 		return false;
3185 
3186 	/* don't handle TX status request here either */
3187 	if (skb->sk && skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)
3188 		return false;
3189 
3190 	if (hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) {
3191 		tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
3192 		tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
3193 		if (tid_tx) {
3194 			if (!test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state))
3195 				return false;
3196 			if (tid_tx->timeout)
3197 				tid_tx->last_tx = jiffies;
3198 		}
3199 	}
3200 
3201 	/* after this point (skb is modified) we cannot return false */
3202 
3203 	if (skb_shared(skb)) {
3204 		struct sk_buff *tmp_skb = skb;
3205 
3206 		skb = skb_clone(skb, GFP_ATOMIC);
3207 		kfree_skb(tmp_skb);
3208 
3209 		if (!skb)
3210 			return true;
3211 	}
3212 
3213 	ieee80211_tx_stats(dev, skb->len + extra_head);
3214 
3215 	if ((hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) &&
3216 	    ieee80211_amsdu_aggregate(sdata, sta, fast_tx, skb))
3217 		return true;
3218 
3219 	/* will not be crypto-handled beyond what we do here, so use false
3220 	 * as the may-encrypt argument for the resize to not account for
3221 	 * more room than we already have in 'extra_head'
3222 	 */
3223 	if (unlikely(ieee80211_skb_resize(sdata, skb,
3224 					  max_t(int, extra_head + hw_headroom -
3225 						     skb_headroom(skb), 0),
3226 					  false))) {
3227 		kfree_skb(skb);
3228 		return true;
3229 	}
3230 
3231 	memcpy(&eth, skb->data, ETH_HLEN - 2);
3232 	hdr = (void *)skb_push(skb, extra_head);
3233 	memcpy(skb->data, fast_tx->hdr, fast_tx->hdr_len);
3234 	memcpy(skb->data + fast_tx->da_offs, eth.h_dest, ETH_ALEN);
3235 	memcpy(skb->data + fast_tx->sa_offs, eth.h_source, ETH_ALEN);
3236 
3237 	memset(info, 0, sizeof(*info));
3238 	info->band = fast_tx->band;
3239 	info->control.vif = &sdata->vif;
3240 	info->flags = IEEE80211_TX_CTL_FIRST_FRAGMENT |
3241 		      IEEE80211_TX_CTL_DONTFRAG |
3242 		      (tid_tx ? IEEE80211_TX_CTL_AMPDU : 0);
3243 
3244 	if (hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) {
3245 		*ieee80211_get_qos_ctl(hdr) = tid;
3246 		if (!sta->sta.txq[0])
3247 			hdr->seq_ctrl = ieee80211_tx_next_seq(sta, tid);
3248 	} else {
3249 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
3250 		hdr->seq_ctrl = cpu_to_le16(sdata->sequence_number);
3251 		sdata->sequence_number += 0x10;
3252 	}
3253 
3254 	if (skb_shinfo(skb)->gso_size)
3255 		sta->tx_stats.msdu[tid] +=
3256 			DIV_ROUND_UP(skb->len, skb_shinfo(skb)->gso_size);
3257 	else
3258 		sta->tx_stats.msdu[tid]++;
3259 
3260 	info->hw_queue = sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
3261 
3262 	__skb_queue_head_init(&tx.skbs);
3263 
3264 	tx.flags = IEEE80211_TX_UNICAST;
3265 	tx.local = local;
3266 	tx.sdata = sdata;
3267 	tx.sta = sta;
3268 	tx.key = fast_tx->key;
3269 
3270 	if (fast_tx->key)
3271 		info->control.hw_key = &fast_tx->key->conf;
3272 
3273 	if (!ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
3274 		tx.skb = skb;
3275 		r = ieee80211_tx_h_rate_ctrl(&tx);
3276 		skb = tx.skb;
3277 		tx.skb = NULL;
3278 
3279 		if (r != TX_CONTINUE) {
3280 			if (r != TX_QUEUED)
3281 				kfree_skb(skb);
3282 			return true;
3283 		}
3284 	}
3285 
3286 	/* statistics normally done by ieee80211_tx_h_stats (but that
3287 	 * has to consider fragmentation, so is more complex)
3288 	 */
3289 	sta->tx_stats.bytes[skb_get_queue_mapping(skb)] += skb->len;
3290 	sta->tx_stats.packets[skb_get_queue_mapping(skb)]++;
3291 
3292 	if (fast_tx->pn_offs) {
3293 		u64 pn;
3294 		u8 *crypto_hdr = skb->data + fast_tx->pn_offs;
3295 
3296 		switch (fast_tx->key->conf.cipher) {
3297 		case WLAN_CIPHER_SUITE_CCMP:
3298 		case WLAN_CIPHER_SUITE_CCMP_256:
3299 		case WLAN_CIPHER_SUITE_GCMP:
3300 		case WLAN_CIPHER_SUITE_GCMP_256:
3301 			pn = atomic64_inc_return(&fast_tx->key->conf.tx_pn);
3302 			crypto_hdr[0] = pn;
3303 			crypto_hdr[1] = pn >> 8;
3304 			crypto_hdr[4] = pn >> 16;
3305 			crypto_hdr[5] = pn >> 24;
3306 			crypto_hdr[6] = pn >> 32;
3307 			crypto_hdr[7] = pn >> 40;
3308 			break;
3309 		}
3310 	}
3311 
3312 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
3313 		sdata = container_of(sdata->bss,
3314 				     struct ieee80211_sub_if_data, u.ap);
3315 
3316 	__skb_queue_tail(&tx.skbs, skb);
3317 	ieee80211_tx_frags(local, &sdata->vif, &sta->sta, &tx.skbs, false);
3318 	return true;
3319 }
3320 
3321 void __ieee80211_subif_start_xmit(struct sk_buff *skb,
3322 				  struct net_device *dev,
3323 				  u32 info_flags)
3324 {
3325 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
3326 	struct sta_info *sta;
3327 	struct sk_buff *next;
3328 
3329 	if (unlikely(skb->len < ETH_HLEN)) {
3330 		kfree_skb(skb);
3331 		return;
3332 	}
3333 
3334 	rcu_read_lock();
3335 
3336 	if (ieee80211_lookup_ra_sta(sdata, skb, &sta))
3337 		goto out_free;
3338 
3339 	if (!IS_ERR_OR_NULL(sta)) {
3340 		struct ieee80211_fast_tx *fast_tx;
3341 
3342 		fast_tx = rcu_dereference(sta->fast_tx);
3343 
3344 		if (fast_tx &&
3345 		    ieee80211_xmit_fast(sdata, dev, sta, fast_tx, skb))
3346 			goto out;
3347 	}
3348 
3349 	if (skb_is_gso(skb)) {
3350 		struct sk_buff *segs;
3351 
3352 		segs = skb_gso_segment(skb, 0);
3353 		if (IS_ERR(segs)) {
3354 			goto out_free;
3355 		} else if (segs) {
3356 			consume_skb(skb);
3357 			skb = segs;
3358 		}
3359 	} else {
3360 		/* we cannot process non-linear frames on this path */
3361 		if (skb_linearize(skb)) {
3362 			kfree_skb(skb);
3363 			goto out;
3364 		}
3365 
3366 		/* the frame could be fragmented, software-encrypted, and other
3367 		 * things so we cannot really handle checksum offload with it -
3368 		 * fix it up in software before we handle anything else.
3369 		 */
3370 		if (skb->ip_summed == CHECKSUM_PARTIAL) {
3371 			skb_set_transport_header(skb,
3372 						 skb_checksum_start_offset(skb));
3373 			if (skb_checksum_help(skb))
3374 				goto out_free;
3375 		}
3376 	}
3377 
3378 	next = skb;
3379 	while (next) {
3380 		skb = next;
3381 		next = skb->next;
3382 
3383 		skb->prev = NULL;
3384 		skb->next = NULL;
3385 
3386 		skb = ieee80211_build_hdr(sdata, skb, info_flags, sta);
3387 		if (IS_ERR(skb))
3388 			goto out;
3389 
3390 		ieee80211_tx_stats(dev, skb->len);
3391 
3392 		ieee80211_xmit(sdata, sta, skb);
3393 	}
3394 	goto out;
3395  out_free:
3396 	kfree_skb(skb);
3397  out:
3398 	rcu_read_unlock();
3399 }
3400 
3401 /**
3402  * ieee80211_subif_start_xmit - netif start_xmit function for 802.3 vifs
3403  * @skb: packet to be sent
3404  * @dev: incoming interface
3405  *
3406  * On failure skb will be freed.
3407  */
3408 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
3409 				       struct net_device *dev)
3410 {
3411 	__ieee80211_subif_start_xmit(skb, dev, 0);
3412 	return NETDEV_TX_OK;
3413 }
3414 
3415 struct sk_buff *
3416 ieee80211_build_data_template(struct ieee80211_sub_if_data *sdata,
3417 			      struct sk_buff *skb, u32 info_flags)
3418 {
3419 	struct ieee80211_hdr *hdr;
3420 	struct ieee80211_tx_data tx = {
3421 		.local = sdata->local,
3422 		.sdata = sdata,
3423 	};
3424 	struct sta_info *sta;
3425 
3426 	rcu_read_lock();
3427 
3428 	if (ieee80211_lookup_ra_sta(sdata, skb, &sta)) {
3429 		kfree_skb(skb);
3430 		skb = ERR_PTR(-EINVAL);
3431 		goto out;
3432 	}
3433 
3434 	skb = ieee80211_build_hdr(sdata, skb, info_flags, sta);
3435 	if (IS_ERR(skb))
3436 		goto out;
3437 
3438 	hdr = (void *)skb->data;
3439 	tx.sta = sta_info_get(sdata, hdr->addr1);
3440 	tx.skb = skb;
3441 
3442 	if (ieee80211_tx_h_select_key(&tx) != TX_CONTINUE) {
3443 		rcu_read_unlock();
3444 		kfree_skb(skb);
3445 		return ERR_PTR(-EINVAL);
3446 	}
3447 
3448 out:
3449 	rcu_read_unlock();
3450 	return skb;
3451 }
3452 
3453 /*
3454  * ieee80211_clear_tx_pending may not be called in a context where
3455  * it is possible that it packets could come in again.
3456  */
3457 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
3458 {
3459 	struct sk_buff *skb;
3460 	int i;
3461 
3462 	for (i = 0; i < local->hw.queues; i++) {
3463 		while ((skb = skb_dequeue(&local->pending[i])) != NULL)
3464 			ieee80211_free_txskb(&local->hw, skb);
3465 	}
3466 }
3467 
3468 /*
3469  * Returns false if the frame couldn't be transmitted but was queued instead,
3470  * which in this case means re-queued -- take as an indication to stop sending
3471  * more pending frames.
3472  */
3473 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
3474 				     struct sk_buff *skb)
3475 {
3476 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3477 	struct ieee80211_sub_if_data *sdata;
3478 	struct sta_info *sta;
3479 	struct ieee80211_hdr *hdr;
3480 	bool result;
3481 	struct ieee80211_chanctx_conf *chanctx_conf;
3482 
3483 	sdata = vif_to_sdata(info->control.vif);
3484 
3485 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
3486 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
3487 		if (unlikely(!chanctx_conf)) {
3488 			dev_kfree_skb(skb);
3489 			return true;
3490 		}
3491 		info->band = chanctx_conf->def.chan->band;
3492 		result = ieee80211_tx(sdata, NULL, skb, true);
3493 	} else {
3494 		struct sk_buff_head skbs;
3495 
3496 		__skb_queue_head_init(&skbs);
3497 		__skb_queue_tail(&skbs, skb);
3498 
3499 		hdr = (struct ieee80211_hdr *)skb->data;
3500 		sta = sta_info_get(sdata, hdr->addr1);
3501 
3502 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
3503 	}
3504 
3505 	return result;
3506 }
3507 
3508 /*
3509  * Transmit all pending packets. Called from tasklet.
3510  */
3511 void ieee80211_tx_pending(unsigned long data)
3512 {
3513 	struct ieee80211_local *local = (struct ieee80211_local *)data;
3514 	unsigned long flags;
3515 	int i;
3516 	bool txok;
3517 
3518 	rcu_read_lock();
3519 
3520 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
3521 	for (i = 0; i < local->hw.queues; i++) {
3522 		/*
3523 		 * If queue is stopped by something other than due to pending
3524 		 * frames, or we have no pending frames, proceed to next queue.
3525 		 */
3526 		if (local->queue_stop_reasons[i] ||
3527 		    skb_queue_empty(&local->pending[i]))
3528 			continue;
3529 
3530 		while (!skb_queue_empty(&local->pending[i])) {
3531 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
3532 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3533 
3534 			if (WARN_ON(!info->control.vif)) {
3535 				ieee80211_free_txskb(&local->hw, skb);
3536 				continue;
3537 			}
3538 
3539 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
3540 						flags);
3541 
3542 			txok = ieee80211_tx_pending_skb(local, skb);
3543 			spin_lock_irqsave(&local->queue_stop_reason_lock,
3544 					  flags);
3545 			if (!txok)
3546 				break;
3547 		}
3548 
3549 		if (skb_queue_empty(&local->pending[i]))
3550 			ieee80211_propagate_queue_wake(local, i);
3551 	}
3552 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
3553 
3554 	rcu_read_unlock();
3555 }
3556 
3557 /* functions for drivers to get certain frames */
3558 
3559 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
3560 				       struct ps_data *ps, struct sk_buff *skb,
3561 				       bool is_template)
3562 {
3563 	u8 *pos, *tim;
3564 	int aid0 = 0;
3565 	int i, have_bits = 0, n1, n2;
3566 
3567 	/* Generate bitmap for TIM only if there are any STAs in power save
3568 	 * mode. */
3569 	if (atomic_read(&ps->num_sta_ps) > 0)
3570 		/* in the hope that this is faster than
3571 		 * checking byte-for-byte */
3572 		have_bits = !bitmap_empty((unsigned long *)ps->tim,
3573 					  IEEE80211_MAX_AID+1);
3574 	if (!is_template) {
3575 		if (ps->dtim_count == 0)
3576 			ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
3577 		else
3578 			ps->dtim_count--;
3579 	}
3580 
3581 	tim = pos = (u8 *) skb_put(skb, 6);
3582 	*pos++ = WLAN_EID_TIM;
3583 	*pos++ = 4;
3584 	*pos++ = ps->dtim_count;
3585 	*pos++ = sdata->vif.bss_conf.dtim_period;
3586 
3587 	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
3588 		aid0 = 1;
3589 
3590 	ps->dtim_bc_mc = aid0 == 1;
3591 
3592 	if (have_bits) {
3593 		/* Find largest even number N1 so that bits numbered 1 through
3594 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
3595 		 * (N2 + 1) x 8 through 2007 are 0. */
3596 		n1 = 0;
3597 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
3598 			if (ps->tim[i]) {
3599 				n1 = i & 0xfe;
3600 				break;
3601 			}
3602 		}
3603 		n2 = n1;
3604 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
3605 			if (ps->tim[i]) {
3606 				n2 = i;
3607 				break;
3608 			}
3609 		}
3610 
3611 		/* Bitmap control */
3612 		*pos++ = n1 | aid0;
3613 		/* Part Virt Bitmap */
3614 		skb_put(skb, n2 - n1);
3615 		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
3616 
3617 		tim[1] = n2 - n1 + 4;
3618 	} else {
3619 		*pos++ = aid0; /* Bitmap control */
3620 		*pos++ = 0; /* Part Virt Bitmap */
3621 	}
3622 }
3623 
3624 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
3625 				    struct ps_data *ps, struct sk_buff *skb,
3626 				    bool is_template)
3627 {
3628 	struct ieee80211_local *local = sdata->local;
3629 
3630 	/*
3631 	 * Not very nice, but we want to allow the driver to call
3632 	 * ieee80211_beacon_get() as a response to the set_tim()
3633 	 * callback. That, however, is already invoked under the
3634 	 * sta_lock to guarantee consistent and race-free update
3635 	 * of the tim bitmap in mac80211 and the driver.
3636 	 */
3637 	if (local->tim_in_locked_section) {
3638 		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
3639 	} else {
3640 		spin_lock_bh(&local->tim_lock);
3641 		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
3642 		spin_unlock_bh(&local->tim_lock);
3643 	}
3644 
3645 	return 0;
3646 }
3647 
3648 static void ieee80211_set_csa(struct ieee80211_sub_if_data *sdata,
3649 			      struct beacon_data *beacon)
3650 {
3651 	struct probe_resp *resp;
3652 	u8 *beacon_data;
3653 	size_t beacon_data_len;
3654 	int i;
3655 	u8 count = beacon->csa_current_counter;
3656 
3657 	switch (sdata->vif.type) {
3658 	case NL80211_IFTYPE_AP:
3659 		beacon_data = beacon->tail;
3660 		beacon_data_len = beacon->tail_len;
3661 		break;
3662 	case NL80211_IFTYPE_ADHOC:
3663 		beacon_data = beacon->head;
3664 		beacon_data_len = beacon->head_len;
3665 		break;
3666 	case NL80211_IFTYPE_MESH_POINT:
3667 		beacon_data = beacon->head;
3668 		beacon_data_len = beacon->head_len;
3669 		break;
3670 	default:
3671 		return;
3672 	}
3673 
3674 	rcu_read_lock();
3675 	for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; ++i) {
3676 		resp = rcu_dereference(sdata->u.ap.probe_resp);
3677 
3678 		if (beacon->csa_counter_offsets[i]) {
3679 			if (WARN_ON_ONCE(beacon->csa_counter_offsets[i] >=
3680 					 beacon_data_len)) {
3681 				rcu_read_unlock();
3682 				return;
3683 			}
3684 
3685 			beacon_data[beacon->csa_counter_offsets[i]] = count;
3686 		}
3687 
3688 		if (sdata->vif.type == NL80211_IFTYPE_AP && resp)
3689 			resp->data[resp->csa_counter_offsets[i]] = count;
3690 	}
3691 	rcu_read_unlock();
3692 }
3693 
3694 static u8 __ieee80211_csa_update_counter(struct beacon_data *beacon)
3695 {
3696 	beacon->csa_current_counter--;
3697 
3698 	/* the counter should never reach 0 */
3699 	WARN_ON_ONCE(!beacon->csa_current_counter);
3700 
3701 	return beacon->csa_current_counter;
3702 }
3703 
3704 u8 ieee80211_csa_update_counter(struct ieee80211_vif *vif)
3705 {
3706 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3707 	struct beacon_data *beacon = NULL;
3708 	u8 count = 0;
3709 
3710 	rcu_read_lock();
3711 
3712 	if (sdata->vif.type == NL80211_IFTYPE_AP)
3713 		beacon = rcu_dereference(sdata->u.ap.beacon);
3714 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
3715 		beacon = rcu_dereference(sdata->u.ibss.presp);
3716 	else if (ieee80211_vif_is_mesh(&sdata->vif))
3717 		beacon = rcu_dereference(sdata->u.mesh.beacon);
3718 
3719 	if (!beacon)
3720 		goto unlock;
3721 
3722 	count = __ieee80211_csa_update_counter(beacon);
3723 
3724 unlock:
3725 	rcu_read_unlock();
3726 	return count;
3727 }
3728 EXPORT_SYMBOL(ieee80211_csa_update_counter);
3729 
3730 bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
3731 {
3732 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3733 	struct beacon_data *beacon = NULL;
3734 	u8 *beacon_data;
3735 	size_t beacon_data_len;
3736 	int ret = false;
3737 
3738 	if (!ieee80211_sdata_running(sdata))
3739 		return false;
3740 
3741 	rcu_read_lock();
3742 	if (vif->type == NL80211_IFTYPE_AP) {
3743 		struct ieee80211_if_ap *ap = &sdata->u.ap;
3744 
3745 		beacon = rcu_dereference(ap->beacon);
3746 		if (WARN_ON(!beacon || !beacon->tail))
3747 			goto out;
3748 		beacon_data = beacon->tail;
3749 		beacon_data_len = beacon->tail_len;
3750 	} else if (vif->type == NL80211_IFTYPE_ADHOC) {
3751 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
3752 
3753 		beacon = rcu_dereference(ifibss->presp);
3754 		if (!beacon)
3755 			goto out;
3756 
3757 		beacon_data = beacon->head;
3758 		beacon_data_len = beacon->head_len;
3759 	} else if (vif->type == NL80211_IFTYPE_MESH_POINT) {
3760 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
3761 
3762 		beacon = rcu_dereference(ifmsh->beacon);
3763 		if (!beacon)
3764 			goto out;
3765 
3766 		beacon_data = beacon->head;
3767 		beacon_data_len = beacon->head_len;
3768 	} else {
3769 		WARN_ON(1);
3770 		goto out;
3771 	}
3772 
3773 	if (!beacon->csa_counter_offsets[0])
3774 		goto out;
3775 
3776 	if (WARN_ON_ONCE(beacon->csa_counter_offsets[0] > beacon_data_len))
3777 		goto out;
3778 
3779 	if (beacon_data[beacon->csa_counter_offsets[0]] == 1)
3780 		ret = true;
3781  out:
3782 	rcu_read_unlock();
3783 
3784 	return ret;
3785 }
3786 EXPORT_SYMBOL(ieee80211_csa_is_complete);
3787 
3788 static struct sk_buff *
3789 __ieee80211_beacon_get(struct ieee80211_hw *hw,
3790 		       struct ieee80211_vif *vif,
3791 		       struct ieee80211_mutable_offsets *offs,
3792 		       bool is_template)
3793 {
3794 	struct ieee80211_local *local = hw_to_local(hw);
3795 	struct beacon_data *beacon = NULL;
3796 	struct sk_buff *skb = NULL;
3797 	struct ieee80211_tx_info *info;
3798 	struct ieee80211_sub_if_data *sdata = NULL;
3799 	enum nl80211_band band;
3800 	struct ieee80211_tx_rate_control txrc;
3801 	struct ieee80211_chanctx_conf *chanctx_conf;
3802 	int csa_off_base = 0;
3803 
3804 	rcu_read_lock();
3805 
3806 	sdata = vif_to_sdata(vif);
3807 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
3808 
3809 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
3810 		goto out;
3811 
3812 	if (offs)
3813 		memset(offs, 0, sizeof(*offs));
3814 
3815 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
3816 		struct ieee80211_if_ap *ap = &sdata->u.ap;
3817 
3818 		beacon = rcu_dereference(ap->beacon);
3819 		if (beacon) {
3820 			if (beacon->csa_counter_offsets[0]) {
3821 				if (!is_template)
3822 					__ieee80211_csa_update_counter(beacon);
3823 
3824 				ieee80211_set_csa(sdata, beacon);
3825 			}
3826 
3827 			/*
3828 			 * headroom, head length,
3829 			 * tail length and maximum TIM length
3830 			 */
3831 			skb = dev_alloc_skb(local->tx_headroom +
3832 					    beacon->head_len +
3833 					    beacon->tail_len + 256 +
3834 					    local->hw.extra_beacon_tailroom);
3835 			if (!skb)
3836 				goto out;
3837 
3838 			skb_reserve(skb, local->tx_headroom);
3839 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
3840 			       beacon->head_len);
3841 
3842 			ieee80211_beacon_add_tim(sdata, &ap->ps, skb,
3843 						 is_template);
3844 
3845 			if (offs) {
3846 				offs->tim_offset = beacon->head_len;
3847 				offs->tim_length = skb->len - beacon->head_len;
3848 
3849 				/* for AP the csa offsets are from tail */
3850 				csa_off_base = skb->len;
3851 			}
3852 
3853 			if (beacon->tail)
3854 				memcpy(skb_put(skb, beacon->tail_len),
3855 				       beacon->tail, beacon->tail_len);
3856 		} else
3857 			goto out;
3858 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
3859 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
3860 		struct ieee80211_hdr *hdr;
3861 
3862 		beacon = rcu_dereference(ifibss->presp);
3863 		if (!beacon)
3864 			goto out;
3865 
3866 		if (beacon->csa_counter_offsets[0]) {
3867 			if (!is_template)
3868 				__ieee80211_csa_update_counter(beacon);
3869 
3870 			ieee80211_set_csa(sdata, beacon);
3871 		}
3872 
3873 		skb = dev_alloc_skb(local->tx_headroom + beacon->head_len +
3874 				    local->hw.extra_beacon_tailroom);
3875 		if (!skb)
3876 			goto out;
3877 		skb_reserve(skb, local->tx_headroom);
3878 		memcpy(skb_put(skb, beacon->head_len), beacon->head,
3879 		       beacon->head_len);
3880 
3881 		hdr = (struct ieee80211_hdr *) skb->data;
3882 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
3883 						 IEEE80211_STYPE_BEACON);
3884 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
3885 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
3886 
3887 		beacon = rcu_dereference(ifmsh->beacon);
3888 		if (!beacon)
3889 			goto out;
3890 
3891 		if (beacon->csa_counter_offsets[0]) {
3892 			if (!is_template)
3893 				/* TODO: For mesh csa_counter is in TU, so
3894 				 * decrementing it by one isn't correct, but
3895 				 * for now we leave it consistent with overall
3896 				 * mac80211's behavior.
3897 				 */
3898 				__ieee80211_csa_update_counter(beacon);
3899 
3900 			ieee80211_set_csa(sdata, beacon);
3901 		}
3902 
3903 		if (ifmsh->sync_ops)
3904 			ifmsh->sync_ops->adjust_tbtt(sdata, beacon);
3905 
3906 		skb = dev_alloc_skb(local->tx_headroom +
3907 				    beacon->head_len +
3908 				    256 + /* TIM IE */
3909 				    beacon->tail_len +
3910 				    local->hw.extra_beacon_tailroom);
3911 		if (!skb)
3912 			goto out;
3913 		skb_reserve(skb, local->tx_headroom);
3914 		memcpy(skb_put(skb, beacon->head_len), beacon->head,
3915 		       beacon->head_len);
3916 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb, is_template);
3917 
3918 		if (offs) {
3919 			offs->tim_offset = beacon->head_len;
3920 			offs->tim_length = skb->len - beacon->head_len;
3921 		}
3922 
3923 		memcpy(skb_put(skb, beacon->tail_len), beacon->tail,
3924 		       beacon->tail_len);
3925 	} else {
3926 		WARN_ON(1);
3927 		goto out;
3928 	}
3929 
3930 	/* CSA offsets */
3931 	if (offs && beacon) {
3932 		int i;
3933 
3934 		for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; i++) {
3935 			u16 csa_off = beacon->csa_counter_offsets[i];
3936 
3937 			if (!csa_off)
3938 				continue;
3939 
3940 			offs->csa_counter_offs[i] = csa_off_base + csa_off;
3941 		}
3942 	}
3943 
3944 	band = chanctx_conf->def.chan->band;
3945 
3946 	info = IEEE80211_SKB_CB(skb);
3947 
3948 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
3949 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
3950 	info->band = band;
3951 
3952 	memset(&txrc, 0, sizeof(txrc));
3953 	txrc.hw = hw;
3954 	txrc.sband = local->hw.wiphy->bands[band];
3955 	txrc.bss_conf = &sdata->vif.bss_conf;
3956 	txrc.skb = skb;
3957 	txrc.reported_rate.idx = -1;
3958 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
3959 	if (txrc.rate_idx_mask == (1 << txrc.sband->n_bitrates) - 1)
3960 		txrc.max_rate_idx = -1;
3961 	else
3962 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
3963 	txrc.bss = true;
3964 	rate_control_get_rate(sdata, NULL, &txrc);
3965 
3966 	info->control.vif = vif;
3967 
3968 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
3969 			IEEE80211_TX_CTL_ASSIGN_SEQ |
3970 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
3971  out:
3972 	rcu_read_unlock();
3973 	return skb;
3974 
3975 }
3976 
3977 struct sk_buff *
3978 ieee80211_beacon_get_template(struct ieee80211_hw *hw,
3979 			      struct ieee80211_vif *vif,
3980 			      struct ieee80211_mutable_offsets *offs)
3981 {
3982 	return __ieee80211_beacon_get(hw, vif, offs, true);
3983 }
3984 EXPORT_SYMBOL(ieee80211_beacon_get_template);
3985 
3986 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
3987 					 struct ieee80211_vif *vif,
3988 					 u16 *tim_offset, u16 *tim_length)
3989 {
3990 	struct ieee80211_mutable_offsets offs = {};
3991 	struct sk_buff *bcn = __ieee80211_beacon_get(hw, vif, &offs, false);
3992 	struct sk_buff *copy;
3993 	struct ieee80211_supported_band *sband;
3994 	int shift;
3995 
3996 	if (!bcn)
3997 		return bcn;
3998 
3999 	if (tim_offset)
4000 		*tim_offset = offs.tim_offset;
4001 
4002 	if (tim_length)
4003 		*tim_length = offs.tim_length;
4004 
4005 	if (ieee80211_hw_check(hw, BEACON_TX_STATUS) ||
4006 	    !hw_to_local(hw)->monitors)
4007 		return bcn;
4008 
4009 	/* send a copy to monitor interfaces */
4010 	copy = skb_copy(bcn, GFP_ATOMIC);
4011 	if (!copy)
4012 		return bcn;
4013 
4014 	shift = ieee80211_vif_get_shift(vif);
4015 	sband = hw->wiphy->bands[ieee80211_get_sdata_band(vif_to_sdata(vif))];
4016 	ieee80211_tx_monitor(hw_to_local(hw), copy, sband, 1, shift, false);
4017 
4018 	return bcn;
4019 }
4020 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
4021 
4022 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
4023 					struct ieee80211_vif *vif)
4024 {
4025 	struct ieee80211_if_ap *ap = NULL;
4026 	struct sk_buff *skb = NULL;
4027 	struct probe_resp *presp = NULL;
4028 	struct ieee80211_hdr *hdr;
4029 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
4030 
4031 	if (sdata->vif.type != NL80211_IFTYPE_AP)
4032 		return NULL;
4033 
4034 	rcu_read_lock();
4035 
4036 	ap = &sdata->u.ap;
4037 	presp = rcu_dereference(ap->probe_resp);
4038 	if (!presp)
4039 		goto out;
4040 
4041 	skb = dev_alloc_skb(presp->len);
4042 	if (!skb)
4043 		goto out;
4044 
4045 	memcpy(skb_put(skb, presp->len), presp->data, presp->len);
4046 
4047 	hdr = (struct ieee80211_hdr *) skb->data;
4048 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
4049 
4050 out:
4051 	rcu_read_unlock();
4052 	return skb;
4053 }
4054 EXPORT_SYMBOL(ieee80211_proberesp_get);
4055 
4056 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
4057 				     struct ieee80211_vif *vif)
4058 {
4059 	struct ieee80211_sub_if_data *sdata;
4060 	struct ieee80211_if_managed *ifmgd;
4061 	struct ieee80211_pspoll *pspoll;
4062 	struct ieee80211_local *local;
4063 	struct sk_buff *skb;
4064 
4065 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
4066 		return NULL;
4067 
4068 	sdata = vif_to_sdata(vif);
4069 	ifmgd = &sdata->u.mgd;
4070 	local = sdata->local;
4071 
4072 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
4073 	if (!skb)
4074 		return NULL;
4075 
4076 	skb_reserve(skb, local->hw.extra_tx_headroom);
4077 
4078 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
4079 	memset(pspoll, 0, sizeof(*pspoll));
4080 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
4081 					    IEEE80211_STYPE_PSPOLL);
4082 	pspoll->aid = cpu_to_le16(ifmgd->aid);
4083 
4084 	/* aid in PS-Poll has its two MSBs each set to 1 */
4085 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
4086 
4087 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
4088 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
4089 
4090 	return skb;
4091 }
4092 EXPORT_SYMBOL(ieee80211_pspoll_get);
4093 
4094 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
4095 				       struct ieee80211_vif *vif)
4096 {
4097 	struct ieee80211_hdr_3addr *nullfunc;
4098 	struct ieee80211_sub_if_data *sdata;
4099 	struct ieee80211_if_managed *ifmgd;
4100 	struct ieee80211_local *local;
4101 	struct sk_buff *skb;
4102 
4103 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
4104 		return NULL;
4105 
4106 	sdata = vif_to_sdata(vif);
4107 	ifmgd = &sdata->u.mgd;
4108 	local = sdata->local;
4109 
4110 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
4111 	if (!skb)
4112 		return NULL;
4113 
4114 	skb_reserve(skb, local->hw.extra_tx_headroom);
4115 
4116 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
4117 							  sizeof(*nullfunc));
4118 	memset(nullfunc, 0, sizeof(*nullfunc));
4119 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
4120 					      IEEE80211_STYPE_NULLFUNC |
4121 					      IEEE80211_FCTL_TODS);
4122 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
4123 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
4124 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
4125 
4126 	return skb;
4127 }
4128 EXPORT_SYMBOL(ieee80211_nullfunc_get);
4129 
4130 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
4131 				       const u8 *src_addr,
4132 				       const u8 *ssid, size_t ssid_len,
4133 				       size_t tailroom)
4134 {
4135 	struct ieee80211_local *local = hw_to_local(hw);
4136 	struct ieee80211_hdr_3addr *hdr;
4137 	struct sk_buff *skb;
4138 	size_t ie_ssid_len;
4139 	u8 *pos;
4140 
4141 	ie_ssid_len = 2 + ssid_len;
4142 
4143 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
4144 			    ie_ssid_len + tailroom);
4145 	if (!skb)
4146 		return NULL;
4147 
4148 	skb_reserve(skb, local->hw.extra_tx_headroom);
4149 
4150 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
4151 	memset(hdr, 0, sizeof(*hdr));
4152 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
4153 					 IEEE80211_STYPE_PROBE_REQ);
4154 	eth_broadcast_addr(hdr->addr1);
4155 	memcpy(hdr->addr2, src_addr, ETH_ALEN);
4156 	eth_broadcast_addr(hdr->addr3);
4157 
4158 	pos = skb_put(skb, ie_ssid_len);
4159 	*pos++ = WLAN_EID_SSID;
4160 	*pos++ = ssid_len;
4161 	if (ssid_len)
4162 		memcpy(pos, ssid, ssid_len);
4163 	pos += ssid_len;
4164 
4165 	return skb;
4166 }
4167 EXPORT_SYMBOL(ieee80211_probereq_get);
4168 
4169 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
4170 		       const void *frame, size_t frame_len,
4171 		       const struct ieee80211_tx_info *frame_txctl,
4172 		       struct ieee80211_rts *rts)
4173 {
4174 	const struct ieee80211_hdr *hdr = frame;
4175 
4176 	rts->frame_control =
4177 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
4178 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
4179 					       frame_txctl);
4180 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
4181 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
4182 }
4183 EXPORT_SYMBOL(ieee80211_rts_get);
4184 
4185 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
4186 			     const void *frame, size_t frame_len,
4187 			     const struct ieee80211_tx_info *frame_txctl,
4188 			     struct ieee80211_cts *cts)
4189 {
4190 	const struct ieee80211_hdr *hdr = frame;
4191 
4192 	cts->frame_control =
4193 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
4194 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
4195 						     frame_len, frame_txctl);
4196 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
4197 }
4198 EXPORT_SYMBOL(ieee80211_ctstoself_get);
4199 
4200 struct sk_buff *
4201 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
4202 			  struct ieee80211_vif *vif)
4203 {
4204 	struct ieee80211_local *local = hw_to_local(hw);
4205 	struct sk_buff *skb = NULL;
4206 	struct ieee80211_tx_data tx;
4207 	struct ieee80211_sub_if_data *sdata;
4208 	struct ps_data *ps;
4209 	struct ieee80211_tx_info *info;
4210 	struct ieee80211_chanctx_conf *chanctx_conf;
4211 
4212 	sdata = vif_to_sdata(vif);
4213 
4214 	rcu_read_lock();
4215 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
4216 
4217 	if (!chanctx_conf)
4218 		goto out;
4219 
4220 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
4221 		struct beacon_data *beacon =
4222 				rcu_dereference(sdata->u.ap.beacon);
4223 
4224 		if (!beacon || !beacon->head)
4225 			goto out;
4226 
4227 		ps = &sdata->u.ap.ps;
4228 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
4229 		ps = &sdata->u.mesh.ps;
4230 	} else {
4231 		goto out;
4232 	}
4233 
4234 	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
4235 		goto out; /* send buffered bc/mc only after DTIM beacon */
4236 
4237 	while (1) {
4238 		skb = skb_dequeue(&ps->bc_buf);
4239 		if (!skb)
4240 			goto out;
4241 		local->total_ps_buffered--;
4242 
4243 		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
4244 			struct ieee80211_hdr *hdr =
4245 				(struct ieee80211_hdr *) skb->data;
4246 			/* more buffered multicast/broadcast frames ==> set
4247 			 * MoreData flag in IEEE 802.11 header to inform PS
4248 			 * STAs */
4249 			hdr->frame_control |=
4250 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
4251 		}
4252 
4253 		if (sdata->vif.type == NL80211_IFTYPE_AP)
4254 			sdata = IEEE80211_DEV_TO_SUB_IF(skb->dev);
4255 		if (!ieee80211_tx_prepare(sdata, &tx, NULL, skb))
4256 			break;
4257 		ieee80211_free_txskb(hw, skb);
4258 	}
4259 
4260 	info = IEEE80211_SKB_CB(skb);
4261 
4262 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
4263 	info->band = chanctx_conf->def.chan->band;
4264 
4265 	if (invoke_tx_handlers(&tx))
4266 		skb = NULL;
4267  out:
4268 	rcu_read_unlock();
4269 
4270 	return skb;
4271 }
4272 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
4273 
4274 int ieee80211_reserve_tid(struct ieee80211_sta *pubsta, u8 tid)
4275 {
4276 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
4277 	struct ieee80211_sub_if_data *sdata = sta->sdata;
4278 	struct ieee80211_local *local = sdata->local;
4279 	int ret;
4280 	u32 queues;
4281 
4282 	lockdep_assert_held(&local->sta_mtx);
4283 
4284 	/* only some cases are supported right now */
4285 	switch (sdata->vif.type) {
4286 	case NL80211_IFTYPE_STATION:
4287 	case NL80211_IFTYPE_AP:
4288 	case NL80211_IFTYPE_AP_VLAN:
4289 		break;
4290 	default:
4291 		WARN_ON(1);
4292 		return -EINVAL;
4293 	}
4294 
4295 	if (WARN_ON(tid >= IEEE80211_NUM_UPS))
4296 		return -EINVAL;
4297 
4298 	if (sta->reserved_tid == tid) {
4299 		ret = 0;
4300 		goto out;
4301 	}
4302 
4303 	if (sta->reserved_tid != IEEE80211_TID_UNRESERVED) {
4304 		sdata_err(sdata, "TID reservation already active\n");
4305 		ret = -EALREADY;
4306 		goto out;
4307 	}
4308 
4309 	ieee80211_stop_vif_queues(sdata->local, sdata,
4310 				  IEEE80211_QUEUE_STOP_REASON_RESERVE_TID);
4311 
4312 	synchronize_net();
4313 
4314 	/* Tear down BA sessions so we stop aggregating on this TID */
4315 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
4316 		set_sta_flag(sta, WLAN_STA_BLOCK_BA);
4317 		__ieee80211_stop_tx_ba_session(sta, tid,
4318 					       AGG_STOP_LOCAL_REQUEST);
4319 	}
4320 
4321 	queues = BIT(sdata->vif.hw_queue[ieee802_1d_to_ac[tid]]);
4322 	__ieee80211_flush_queues(local, sdata, queues, false);
4323 
4324 	sta->reserved_tid = tid;
4325 
4326 	ieee80211_wake_vif_queues(local, sdata,
4327 				  IEEE80211_QUEUE_STOP_REASON_RESERVE_TID);
4328 
4329 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION))
4330 		clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
4331 
4332 	ret = 0;
4333  out:
4334 	return ret;
4335 }
4336 EXPORT_SYMBOL(ieee80211_reserve_tid);
4337 
4338 void ieee80211_unreserve_tid(struct ieee80211_sta *pubsta, u8 tid)
4339 {
4340 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
4341 	struct ieee80211_sub_if_data *sdata = sta->sdata;
4342 
4343 	lockdep_assert_held(&sdata->local->sta_mtx);
4344 
4345 	/* only some cases are supported right now */
4346 	switch (sdata->vif.type) {
4347 	case NL80211_IFTYPE_STATION:
4348 	case NL80211_IFTYPE_AP:
4349 	case NL80211_IFTYPE_AP_VLAN:
4350 		break;
4351 	default:
4352 		WARN_ON(1);
4353 		return;
4354 	}
4355 
4356 	if (tid != sta->reserved_tid) {
4357 		sdata_err(sdata, "TID to unreserve (%d) isn't reserved\n", tid);
4358 		return;
4359 	}
4360 
4361 	sta->reserved_tid = IEEE80211_TID_UNRESERVED;
4362 }
4363 EXPORT_SYMBOL(ieee80211_unreserve_tid);
4364 
4365 void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
4366 				 struct sk_buff *skb, int tid,
4367 				 enum nl80211_band band)
4368 {
4369 	int ac = ieee802_1d_to_ac[tid & 7];
4370 
4371 	skb_reset_mac_header(skb);
4372 	skb_set_queue_mapping(skb, ac);
4373 	skb->priority = tid;
4374 
4375 	skb->dev = sdata->dev;
4376 
4377 	/*
4378 	 * The other path calling ieee80211_xmit is from the tasklet,
4379 	 * and while we can handle concurrent transmissions locking
4380 	 * requirements are that we do not come into tx with bhs on.
4381 	 */
4382 	local_bh_disable();
4383 	IEEE80211_SKB_CB(skb)->band = band;
4384 	ieee80211_xmit(sdata, NULL, skb);
4385 	local_bh_enable();
4386 }
4387