xref: /openbmc/linux/net/mac80211/tx.c (revision eb3fcf00)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
6  * Copyright 2013-2014  Intel Mobile Communications GmbH
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  *
13  * Transmit and frame generation functions.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/skbuff.h>
19 #include <linux/etherdevice.h>
20 #include <linux/bitmap.h>
21 #include <linux/rcupdate.h>
22 #include <linux/export.h>
23 #include <net/net_namespace.h>
24 #include <net/ieee80211_radiotap.h>
25 #include <net/cfg80211.h>
26 #include <net/mac80211.h>
27 #include <asm/unaligned.h>
28 
29 #include "ieee80211_i.h"
30 #include "driver-ops.h"
31 #include "led.h"
32 #include "mesh.h"
33 #include "wep.h"
34 #include "wpa.h"
35 #include "wme.h"
36 #include "rate.h"
37 
38 /* misc utils */
39 
40 static inline void ieee80211_tx_stats(struct net_device *dev, u32 len)
41 {
42 	struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
43 
44 	u64_stats_update_begin(&tstats->syncp);
45 	tstats->tx_packets++;
46 	tstats->tx_bytes += len;
47 	u64_stats_update_end(&tstats->syncp);
48 }
49 
50 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx,
51 				 struct sk_buff *skb, int group_addr,
52 				 int next_frag_len)
53 {
54 	int rate, mrate, erp, dur, i, shift = 0;
55 	struct ieee80211_rate *txrate;
56 	struct ieee80211_local *local = tx->local;
57 	struct ieee80211_supported_band *sband;
58 	struct ieee80211_hdr *hdr;
59 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
60 	struct ieee80211_chanctx_conf *chanctx_conf;
61 	u32 rate_flags = 0;
62 
63 	rcu_read_lock();
64 	chanctx_conf = rcu_dereference(tx->sdata->vif.chanctx_conf);
65 	if (chanctx_conf) {
66 		shift = ieee80211_chandef_get_shift(&chanctx_conf->def);
67 		rate_flags = ieee80211_chandef_rate_flags(&chanctx_conf->def);
68 	}
69 	rcu_read_unlock();
70 
71 	/* assume HW handles this */
72 	if (tx->rate.flags & (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))
73 		return 0;
74 
75 	/* uh huh? */
76 	if (WARN_ON_ONCE(tx->rate.idx < 0))
77 		return 0;
78 
79 	sband = local->hw.wiphy->bands[info->band];
80 	txrate = &sband->bitrates[tx->rate.idx];
81 
82 	erp = txrate->flags & IEEE80211_RATE_ERP_G;
83 
84 	/*
85 	 * data and mgmt (except PS Poll):
86 	 * - during CFP: 32768
87 	 * - during contention period:
88 	 *   if addr1 is group address: 0
89 	 *   if more fragments = 0 and addr1 is individual address: time to
90 	 *      transmit one ACK plus SIFS
91 	 *   if more fragments = 1 and addr1 is individual address: time to
92 	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
93 	 *
94 	 * IEEE 802.11, 9.6:
95 	 * - control response frame (CTS or ACK) shall be transmitted using the
96 	 *   same rate as the immediately previous frame in the frame exchange
97 	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
98 	 *   at the highest possible rate belonging to the PHY rates in the
99 	 *   BSSBasicRateSet
100 	 */
101 	hdr = (struct ieee80211_hdr *)skb->data;
102 	if (ieee80211_is_ctl(hdr->frame_control)) {
103 		/* TODO: These control frames are not currently sent by
104 		 * mac80211, but should they be implemented, this function
105 		 * needs to be updated to support duration field calculation.
106 		 *
107 		 * RTS: time needed to transmit pending data/mgmt frame plus
108 		 *    one CTS frame plus one ACK frame plus 3 x SIFS
109 		 * CTS: duration of immediately previous RTS minus time
110 		 *    required to transmit CTS and its SIFS
111 		 * ACK: 0 if immediately previous directed data/mgmt had
112 		 *    more=0, with more=1 duration in ACK frame is duration
113 		 *    from previous frame minus time needed to transmit ACK
114 		 *    and its SIFS
115 		 * PS Poll: BIT(15) | BIT(14) | aid
116 		 */
117 		return 0;
118 	}
119 
120 	/* data/mgmt */
121 	if (0 /* FIX: data/mgmt during CFP */)
122 		return cpu_to_le16(32768);
123 
124 	if (group_addr) /* Group address as the destination - no ACK */
125 		return 0;
126 
127 	/* Individual destination address:
128 	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
129 	 * CTS and ACK frames shall be transmitted using the highest rate in
130 	 * basic rate set that is less than or equal to the rate of the
131 	 * immediately previous frame and that is using the same modulation
132 	 * (CCK or OFDM). If no basic rate set matches with these requirements,
133 	 * the highest mandatory rate of the PHY that is less than or equal to
134 	 * the rate of the previous frame is used.
135 	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
136 	 */
137 	rate = -1;
138 	/* use lowest available if everything fails */
139 	mrate = sband->bitrates[0].bitrate;
140 	for (i = 0; i < sband->n_bitrates; i++) {
141 		struct ieee80211_rate *r = &sband->bitrates[i];
142 
143 		if (r->bitrate > txrate->bitrate)
144 			break;
145 
146 		if ((rate_flags & r->flags) != rate_flags)
147 			continue;
148 
149 		if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
150 			rate = DIV_ROUND_UP(r->bitrate, 1 << shift);
151 
152 		switch (sband->band) {
153 		case IEEE80211_BAND_2GHZ: {
154 			u32 flag;
155 			if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
156 				flag = IEEE80211_RATE_MANDATORY_G;
157 			else
158 				flag = IEEE80211_RATE_MANDATORY_B;
159 			if (r->flags & flag)
160 				mrate = r->bitrate;
161 			break;
162 		}
163 		case IEEE80211_BAND_5GHZ:
164 			if (r->flags & IEEE80211_RATE_MANDATORY_A)
165 				mrate = r->bitrate;
166 			break;
167 		case IEEE80211_BAND_60GHZ:
168 			/* TODO, for now fall through */
169 		case IEEE80211_NUM_BANDS:
170 			WARN_ON(1);
171 			break;
172 		}
173 	}
174 	if (rate == -1) {
175 		/* No matching basic rate found; use highest suitable mandatory
176 		 * PHY rate */
177 		rate = DIV_ROUND_UP(mrate, 1 << shift);
178 	}
179 
180 	/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
181 	if (ieee80211_is_data_qos(hdr->frame_control) &&
182 	    *(ieee80211_get_qos_ctl(hdr)) & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
183 		dur = 0;
184 	else
185 		/* Time needed to transmit ACK
186 		 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
187 		 * to closest integer */
188 		dur = ieee80211_frame_duration(sband->band, 10, rate, erp,
189 				tx->sdata->vif.bss_conf.use_short_preamble,
190 				shift);
191 
192 	if (next_frag_len) {
193 		/* Frame is fragmented: duration increases with time needed to
194 		 * transmit next fragment plus ACK and 2 x SIFS. */
195 		dur *= 2; /* ACK + SIFS */
196 		/* next fragment */
197 		dur += ieee80211_frame_duration(sband->band, next_frag_len,
198 				txrate->bitrate, erp,
199 				tx->sdata->vif.bss_conf.use_short_preamble,
200 				shift);
201 	}
202 
203 	return cpu_to_le16(dur);
204 }
205 
206 /* tx handlers */
207 static ieee80211_tx_result debug_noinline
208 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
209 {
210 	struct ieee80211_local *local = tx->local;
211 	struct ieee80211_if_managed *ifmgd;
212 
213 	/* driver doesn't support power save */
214 	if (!ieee80211_hw_check(&local->hw, SUPPORTS_PS))
215 		return TX_CONTINUE;
216 
217 	/* hardware does dynamic power save */
218 	if (ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS))
219 		return TX_CONTINUE;
220 
221 	/* dynamic power save disabled */
222 	if (local->hw.conf.dynamic_ps_timeout <= 0)
223 		return TX_CONTINUE;
224 
225 	/* we are scanning, don't enable power save */
226 	if (local->scanning)
227 		return TX_CONTINUE;
228 
229 	if (!local->ps_sdata)
230 		return TX_CONTINUE;
231 
232 	/* No point if we're going to suspend */
233 	if (local->quiescing)
234 		return TX_CONTINUE;
235 
236 	/* dynamic ps is supported only in managed mode */
237 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
238 		return TX_CONTINUE;
239 
240 	ifmgd = &tx->sdata->u.mgd;
241 
242 	/*
243 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
244 	 * u-apsd enabled and the frame is in voip class. This effectively
245 	 * means that even if all access categories have u-apsd enabled, in
246 	 * practise u-apsd is only used with the voip ac. This is a
247 	 * workaround for the case when received voip class packets do not
248 	 * have correct qos tag for some reason, due the network or the
249 	 * peer application.
250 	 *
251 	 * Note: ifmgd->uapsd_queues access is racy here. If the value is
252 	 * changed via debugfs, user needs to reassociate manually to have
253 	 * everything in sync.
254 	 */
255 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
256 	    (ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
257 	    skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
258 		return TX_CONTINUE;
259 
260 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
261 		ieee80211_stop_queues_by_reason(&local->hw,
262 						IEEE80211_MAX_QUEUE_MAP,
263 						IEEE80211_QUEUE_STOP_REASON_PS,
264 						false);
265 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
266 		ieee80211_queue_work(&local->hw,
267 				     &local->dynamic_ps_disable_work);
268 	}
269 
270 	/* Don't restart the timer if we're not disassociated */
271 	if (!ifmgd->associated)
272 		return TX_CONTINUE;
273 
274 	mod_timer(&local->dynamic_ps_timer, jiffies +
275 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
276 
277 	return TX_CONTINUE;
278 }
279 
280 static ieee80211_tx_result debug_noinline
281 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
282 {
283 
284 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
285 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
286 	bool assoc = false;
287 
288 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
289 		return TX_CONTINUE;
290 
291 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
292 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
293 	    !ieee80211_is_probe_req(hdr->frame_control) &&
294 	    !ieee80211_is_nullfunc(hdr->frame_control))
295 		/*
296 		 * When software scanning only nullfunc frames (to notify
297 		 * the sleep state to the AP) and probe requests (for the
298 		 * active scan) are allowed, all other frames should not be
299 		 * sent and we should not get here, but if we do
300 		 * nonetheless, drop them to avoid sending them
301 		 * off-channel. See the link below and
302 		 * ieee80211_start_scan() for more.
303 		 *
304 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
305 		 */
306 		return TX_DROP;
307 
308 	if (tx->sdata->vif.type == NL80211_IFTYPE_OCB)
309 		return TX_CONTINUE;
310 
311 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
312 		return TX_CONTINUE;
313 
314 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
315 		return TX_CONTINUE;
316 
317 	if (tx->sta)
318 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
319 
320 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
321 		if (unlikely(!assoc &&
322 			     ieee80211_is_data(hdr->frame_control))) {
323 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
324 			sdata_info(tx->sdata,
325 				   "dropped data frame to not associated station %pM\n",
326 				   hdr->addr1);
327 #endif
328 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
329 			return TX_DROP;
330 		}
331 	} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
332 			    ieee80211_is_data(hdr->frame_control) &&
333 			    !atomic_read(&tx->sdata->u.ap.num_mcast_sta))) {
334 		/*
335 		 * No associated STAs - no need to send multicast
336 		 * frames.
337 		 */
338 		return TX_DROP;
339 	}
340 
341 	return TX_CONTINUE;
342 }
343 
344 /* This function is called whenever the AP is about to exceed the maximum limit
345  * of buffered frames for power saving STAs. This situation should not really
346  * happen often during normal operation, so dropping the oldest buffered packet
347  * from each queue should be OK to make some room for new frames. */
348 static void purge_old_ps_buffers(struct ieee80211_local *local)
349 {
350 	int total = 0, purged = 0;
351 	struct sk_buff *skb;
352 	struct ieee80211_sub_if_data *sdata;
353 	struct sta_info *sta;
354 
355 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
356 		struct ps_data *ps;
357 
358 		if (sdata->vif.type == NL80211_IFTYPE_AP)
359 			ps = &sdata->u.ap.ps;
360 		else if (ieee80211_vif_is_mesh(&sdata->vif))
361 			ps = &sdata->u.mesh.ps;
362 		else
363 			continue;
364 
365 		skb = skb_dequeue(&ps->bc_buf);
366 		if (skb) {
367 			purged++;
368 			dev_kfree_skb(skb);
369 		}
370 		total += skb_queue_len(&ps->bc_buf);
371 	}
372 
373 	/*
374 	 * Drop one frame from each station from the lowest-priority
375 	 * AC that has frames at all.
376 	 */
377 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
378 		int ac;
379 
380 		for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
381 			skb = skb_dequeue(&sta->ps_tx_buf[ac]);
382 			total += skb_queue_len(&sta->ps_tx_buf[ac]);
383 			if (skb) {
384 				purged++;
385 				ieee80211_free_txskb(&local->hw, skb);
386 				break;
387 			}
388 		}
389 	}
390 
391 	local->total_ps_buffered = total;
392 	ps_dbg_hw(&local->hw, "PS buffers full - purged %d frames\n", purged);
393 }
394 
395 static ieee80211_tx_result
396 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
397 {
398 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
399 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
400 	struct ps_data *ps;
401 
402 	/*
403 	 * broadcast/multicast frame
404 	 *
405 	 * If any of the associated/peer stations is in power save mode,
406 	 * the frame is buffered to be sent after DTIM beacon frame.
407 	 * This is done either by the hardware or us.
408 	 */
409 
410 	/* powersaving STAs currently only in AP/VLAN/mesh mode */
411 	if (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
412 	    tx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
413 		if (!tx->sdata->bss)
414 			return TX_CONTINUE;
415 
416 		ps = &tx->sdata->bss->ps;
417 	} else if (ieee80211_vif_is_mesh(&tx->sdata->vif)) {
418 		ps = &tx->sdata->u.mesh.ps;
419 	} else {
420 		return TX_CONTINUE;
421 	}
422 
423 
424 	/* no buffering for ordered frames */
425 	if (ieee80211_has_order(hdr->frame_control))
426 		return TX_CONTINUE;
427 
428 	if (ieee80211_is_probe_req(hdr->frame_control))
429 		return TX_CONTINUE;
430 
431 	if (ieee80211_hw_check(&tx->local->hw, QUEUE_CONTROL))
432 		info->hw_queue = tx->sdata->vif.cab_queue;
433 
434 	/* no stations in PS mode */
435 	if (!atomic_read(&ps->num_sta_ps))
436 		return TX_CONTINUE;
437 
438 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
439 
440 	/* device releases frame after DTIM beacon */
441 	if (!ieee80211_hw_check(&tx->local->hw, HOST_BROADCAST_PS_BUFFERING))
442 		return TX_CONTINUE;
443 
444 	/* buffered in mac80211 */
445 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
446 		purge_old_ps_buffers(tx->local);
447 
448 	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
449 		ps_dbg(tx->sdata,
450 		       "BC TX buffer full - dropping the oldest frame\n");
451 		dev_kfree_skb(skb_dequeue(&ps->bc_buf));
452 	} else
453 		tx->local->total_ps_buffered++;
454 
455 	skb_queue_tail(&ps->bc_buf, tx->skb);
456 
457 	return TX_QUEUED;
458 }
459 
460 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
461 			     struct sk_buff *skb)
462 {
463 	if (!ieee80211_is_mgmt(fc))
464 		return 0;
465 
466 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
467 		return 0;
468 
469 	if (!ieee80211_is_robust_mgmt_frame(skb))
470 		return 0;
471 
472 	return 1;
473 }
474 
475 static ieee80211_tx_result
476 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
477 {
478 	struct sta_info *sta = tx->sta;
479 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
480 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
481 	struct ieee80211_local *local = tx->local;
482 
483 	if (unlikely(!sta))
484 		return TX_CONTINUE;
485 
486 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
487 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
488 		      test_sta_flag(sta, WLAN_STA_PS_DELIVER)) &&
489 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
490 		int ac = skb_get_queue_mapping(tx->skb);
491 
492 		if (ieee80211_is_mgmt(hdr->frame_control) &&
493 		    !ieee80211_is_bufferable_mmpdu(hdr->frame_control)) {
494 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
495 			return TX_CONTINUE;
496 		}
497 
498 		ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
499 		       sta->sta.addr, sta->sta.aid, ac);
500 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
501 			purge_old_ps_buffers(tx->local);
502 
503 		/* sync with ieee80211_sta_ps_deliver_wakeup */
504 		spin_lock(&sta->ps_lock);
505 		/*
506 		 * STA woke up the meantime and all the frames on ps_tx_buf have
507 		 * been queued to pending queue. No reordering can happen, go
508 		 * ahead and Tx the packet.
509 		 */
510 		if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
511 		    !test_sta_flag(sta, WLAN_STA_PS_DRIVER) &&
512 		    !test_sta_flag(sta, WLAN_STA_PS_DELIVER)) {
513 			spin_unlock(&sta->ps_lock);
514 			return TX_CONTINUE;
515 		}
516 
517 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
518 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
519 			ps_dbg(tx->sdata,
520 			       "STA %pM TX buffer for AC %d full - dropping oldest frame\n",
521 			       sta->sta.addr, ac);
522 			ieee80211_free_txskb(&local->hw, old);
523 		} else
524 			tx->local->total_ps_buffered++;
525 
526 		info->control.jiffies = jiffies;
527 		info->control.vif = &tx->sdata->vif;
528 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
529 		info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
530 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
531 		spin_unlock(&sta->ps_lock);
532 
533 		if (!timer_pending(&local->sta_cleanup))
534 			mod_timer(&local->sta_cleanup,
535 				  round_jiffies(jiffies +
536 						STA_INFO_CLEANUP_INTERVAL));
537 
538 		/*
539 		 * We queued up some frames, so the TIM bit might
540 		 * need to be set, recalculate it.
541 		 */
542 		sta_info_recalc_tim(sta);
543 
544 		return TX_QUEUED;
545 	} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
546 		ps_dbg(tx->sdata,
547 		       "STA %pM in PS mode, but polling/in SP -> send frame\n",
548 		       sta->sta.addr);
549 	}
550 
551 	return TX_CONTINUE;
552 }
553 
554 static ieee80211_tx_result debug_noinline
555 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
556 {
557 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
558 		return TX_CONTINUE;
559 
560 	if (tx->flags & IEEE80211_TX_UNICAST)
561 		return ieee80211_tx_h_unicast_ps_buf(tx);
562 	else
563 		return ieee80211_tx_h_multicast_ps_buf(tx);
564 }
565 
566 static ieee80211_tx_result debug_noinline
567 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
568 {
569 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
570 
571 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol)) {
572 		if (tx->sdata->control_port_no_encrypt)
573 			info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
574 		info->control.flags |= IEEE80211_TX_CTRL_PORT_CTRL_PROTO;
575 		info->flags |= IEEE80211_TX_CTL_USE_MINRATE;
576 	}
577 
578 	return TX_CONTINUE;
579 }
580 
581 static ieee80211_tx_result debug_noinline
582 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
583 {
584 	struct ieee80211_key *key;
585 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
586 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
587 
588 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
589 		tx->key = NULL;
590 	else if (tx->sta &&
591 		 (key = rcu_dereference(tx->sta->ptk[tx->sta->ptk_idx])))
592 		tx->key = key;
593 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
594 		 is_multicast_ether_addr(hdr->addr1) &&
595 		 ieee80211_is_robust_mgmt_frame(tx->skb) &&
596 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
597 		tx->key = key;
598 	else if (is_multicast_ether_addr(hdr->addr1) &&
599 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
600 		tx->key = key;
601 	else if (!is_multicast_ether_addr(hdr->addr1) &&
602 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
603 		tx->key = key;
604 	else
605 		tx->key = NULL;
606 
607 	if (tx->key) {
608 		bool skip_hw = false;
609 
610 		/* TODO: add threshold stuff again */
611 
612 		switch (tx->key->conf.cipher) {
613 		case WLAN_CIPHER_SUITE_WEP40:
614 		case WLAN_CIPHER_SUITE_WEP104:
615 		case WLAN_CIPHER_SUITE_TKIP:
616 			if (!ieee80211_is_data_present(hdr->frame_control))
617 				tx->key = NULL;
618 			break;
619 		case WLAN_CIPHER_SUITE_CCMP:
620 		case WLAN_CIPHER_SUITE_CCMP_256:
621 		case WLAN_CIPHER_SUITE_GCMP:
622 		case WLAN_CIPHER_SUITE_GCMP_256:
623 			if (!ieee80211_is_data_present(hdr->frame_control) &&
624 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
625 					       tx->skb))
626 				tx->key = NULL;
627 			else
628 				skip_hw = (tx->key->conf.flags &
629 					   IEEE80211_KEY_FLAG_SW_MGMT_TX) &&
630 					ieee80211_is_mgmt(hdr->frame_control);
631 			break;
632 		case WLAN_CIPHER_SUITE_AES_CMAC:
633 		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
634 		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
635 		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
636 			if (!ieee80211_is_mgmt(hdr->frame_control))
637 				tx->key = NULL;
638 			break;
639 		}
640 
641 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED &&
642 			     !ieee80211_is_deauth(hdr->frame_control)))
643 			return TX_DROP;
644 
645 		if (!skip_hw && tx->key &&
646 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
647 			info->control.hw_key = &tx->key->conf;
648 	}
649 
650 	return TX_CONTINUE;
651 }
652 
653 static ieee80211_tx_result debug_noinline
654 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
655 {
656 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
657 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
658 	struct ieee80211_supported_band *sband;
659 	u32 len;
660 	struct ieee80211_tx_rate_control txrc;
661 	struct ieee80211_sta_rates *ratetbl = NULL;
662 	bool assoc = false;
663 
664 	memset(&txrc, 0, sizeof(txrc));
665 
666 	sband = tx->local->hw.wiphy->bands[info->band];
667 
668 	len = min_t(u32, tx->skb->len + FCS_LEN,
669 			 tx->local->hw.wiphy->frag_threshold);
670 
671 	/* set up the tx rate control struct we give the RC algo */
672 	txrc.hw = &tx->local->hw;
673 	txrc.sband = sband;
674 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
675 	txrc.skb = tx->skb;
676 	txrc.reported_rate.idx = -1;
677 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
678 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
679 		txrc.max_rate_idx = -1;
680 	else
681 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
682 
683 	if (tx->sdata->rc_has_mcs_mask[info->band])
684 		txrc.rate_idx_mcs_mask =
685 			tx->sdata->rc_rateidx_mcs_mask[info->band];
686 
687 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
688 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
689 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC ||
690 		    tx->sdata->vif.type == NL80211_IFTYPE_OCB);
691 
692 	/* set up RTS protection if desired */
693 	if (len > tx->local->hw.wiphy->rts_threshold) {
694 		txrc.rts = true;
695 	}
696 
697 	info->control.use_rts = txrc.rts;
698 	info->control.use_cts_prot = tx->sdata->vif.bss_conf.use_cts_prot;
699 
700 	/*
701 	 * Use short preamble if the BSS can handle it, but not for
702 	 * management frames unless we know the receiver can handle
703 	 * that -- the management frame might be to a station that
704 	 * just wants a probe response.
705 	 */
706 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
707 	    (ieee80211_is_data(hdr->frame_control) ||
708 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
709 		txrc.short_preamble = true;
710 
711 	info->control.short_preamble = txrc.short_preamble;
712 
713 	if (tx->sta)
714 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
715 
716 	/*
717 	 * Lets not bother rate control if we're associated and cannot
718 	 * talk to the sta. This should not happen.
719 	 */
720 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
721 		 !rate_usable_index_exists(sband, &tx->sta->sta),
722 		 "%s: Dropped data frame as no usable bitrate found while "
723 		 "scanning and associated. Target station: "
724 		 "%pM on %d GHz band\n",
725 		 tx->sdata->name, hdr->addr1,
726 		 info->band ? 5 : 2))
727 		return TX_DROP;
728 
729 	/*
730 	 * If we're associated with the sta at this point we know we can at
731 	 * least send the frame at the lowest bit rate.
732 	 */
733 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
734 
735 	if (tx->sta && !info->control.skip_table)
736 		ratetbl = rcu_dereference(tx->sta->sta.rates);
737 
738 	if (unlikely(info->control.rates[0].idx < 0)) {
739 		if (ratetbl) {
740 			struct ieee80211_tx_rate rate = {
741 				.idx = ratetbl->rate[0].idx,
742 				.flags = ratetbl->rate[0].flags,
743 				.count = ratetbl->rate[0].count
744 			};
745 
746 			if (ratetbl->rate[0].idx < 0)
747 				return TX_DROP;
748 
749 			tx->rate = rate;
750 		} else {
751 			return TX_DROP;
752 		}
753 	} else {
754 		tx->rate = info->control.rates[0];
755 	}
756 
757 	if (txrc.reported_rate.idx < 0) {
758 		txrc.reported_rate = tx->rate;
759 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
760 			tx->sta->last_tx_rate = txrc.reported_rate;
761 	} else if (tx->sta)
762 		tx->sta->last_tx_rate = txrc.reported_rate;
763 
764 	if (ratetbl)
765 		return TX_CONTINUE;
766 
767 	if (unlikely(!info->control.rates[0].count))
768 		info->control.rates[0].count = 1;
769 
770 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
771 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
772 		info->control.rates[0].count = 1;
773 
774 	return TX_CONTINUE;
775 }
776 
777 static __le16 ieee80211_tx_next_seq(struct sta_info *sta, int tid)
778 {
779 	u16 *seq = &sta->tid_seq[tid];
780 	__le16 ret = cpu_to_le16(*seq);
781 
782 	/* Increase the sequence number. */
783 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
784 
785 	return ret;
786 }
787 
788 static ieee80211_tx_result debug_noinline
789 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
790 {
791 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
792 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
793 	u8 *qc;
794 	int tid;
795 
796 	/*
797 	 * Packet injection may want to control the sequence
798 	 * number, if we have no matching interface then we
799 	 * neither assign one ourselves nor ask the driver to.
800 	 */
801 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
802 		return TX_CONTINUE;
803 
804 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
805 		return TX_CONTINUE;
806 
807 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
808 		return TX_CONTINUE;
809 
810 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
811 		return TX_CONTINUE;
812 
813 	/*
814 	 * Anything but QoS data that has a sequence number field
815 	 * (is long enough) gets a sequence number from the global
816 	 * counter.  QoS data frames with a multicast destination
817 	 * also use the global counter (802.11-2012 9.3.2.10).
818 	 */
819 	if (!ieee80211_is_data_qos(hdr->frame_control) ||
820 	    is_multicast_ether_addr(hdr->addr1)) {
821 		/* driver should assign sequence number */
822 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
823 		/* for pure STA mode without beacons, we can do it */
824 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
825 		tx->sdata->sequence_number += 0x10;
826 		if (tx->sta)
827 			tx->sta->tx_msdu[IEEE80211_NUM_TIDS]++;
828 		return TX_CONTINUE;
829 	}
830 
831 	/*
832 	 * This should be true for injected/management frames only, for
833 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
834 	 * above since they are not QoS-data frames.
835 	 */
836 	if (!tx->sta)
837 		return TX_CONTINUE;
838 
839 	/* include per-STA, per-TID sequence counter */
840 
841 	qc = ieee80211_get_qos_ctl(hdr);
842 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
843 	tx->sta->tx_msdu[tid]++;
844 
845 	if (!tx->sta->sta.txq[0])
846 		hdr->seq_ctrl = ieee80211_tx_next_seq(tx->sta, tid);
847 
848 	return TX_CONTINUE;
849 }
850 
851 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
852 			      struct sk_buff *skb, int hdrlen,
853 			      int frag_threshold)
854 {
855 	struct ieee80211_local *local = tx->local;
856 	struct ieee80211_tx_info *info;
857 	struct sk_buff *tmp;
858 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
859 	int pos = hdrlen + per_fragm;
860 	int rem = skb->len - hdrlen - per_fragm;
861 
862 	if (WARN_ON(rem < 0))
863 		return -EINVAL;
864 
865 	/* first fragment was already added to queue by caller */
866 
867 	while (rem) {
868 		int fraglen = per_fragm;
869 
870 		if (fraglen > rem)
871 			fraglen = rem;
872 		rem -= fraglen;
873 		tmp = dev_alloc_skb(local->tx_headroom +
874 				    frag_threshold +
875 				    tx->sdata->encrypt_headroom +
876 				    IEEE80211_ENCRYPT_TAILROOM);
877 		if (!tmp)
878 			return -ENOMEM;
879 
880 		__skb_queue_tail(&tx->skbs, tmp);
881 
882 		skb_reserve(tmp,
883 			    local->tx_headroom + tx->sdata->encrypt_headroom);
884 
885 		/* copy control information */
886 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
887 
888 		info = IEEE80211_SKB_CB(tmp);
889 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
890 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
891 
892 		if (rem)
893 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
894 
895 		skb_copy_queue_mapping(tmp, skb);
896 		tmp->priority = skb->priority;
897 		tmp->dev = skb->dev;
898 
899 		/* copy header and data */
900 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
901 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
902 
903 		pos += fraglen;
904 	}
905 
906 	/* adjust first fragment's length */
907 	skb_trim(skb, hdrlen + per_fragm);
908 	return 0;
909 }
910 
911 static ieee80211_tx_result debug_noinline
912 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
913 {
914 	struct sk_buff *skb = tx->skb;
915 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
916 	struct ieee80211_hdr *hdr = (void *)skb->data;
917 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
918 	int hdrlen;
919 	int fragnum;
920 
921 	/* no matter what happens, tx->skb moves to tx->skbs */
922 	__skb_queue_tail(&tx->skbs, skb);
923 	tx->skb = NULL;
924 
925 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
926 		return TX_CONTINUE;
927 
928 	if (tx->local->ops->set_frag_threshold)
929 		return TX_CONTINUE;
930 
931 	/*
932 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
933 	 * This scenario is handled in ieee80211_tx_prepare but extra
934 	 * caution taken here as fragmented ampdu may cause Tx stop.
935 	 */
936 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
937 		return TX_DROP;
938 
939 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
940 
941 	/* internal error, why isn't DONTFRAG set? */
942 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
943 		return TX_DROP;
944 
945 	/*
946 	 * Now fragment the frame. This will allocate all the fragments and
947 	 * chain them (using skb as the first fragment) to skb->next.
948 	 * During transmission, we will remove the successfully transmitted
949 	 * fragments from this list. When the low-level driver rejects one
950 	 * of the fragments then we will simply pretend to accept the skb
951 	 * but store it away as pending.
952 	 */
953 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
954 		return TX_DROP;
955 
956 	/* update duration/seq/flags of fragments */
957 	fragnum = 0;
958 
959 	skb_queue_walk(&tx->skbs, skb) {
960 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
961 
962 		hdr = (void *)skb->data;
963 		info = IEEE80211_SKB_CB(skb);
964 
965 		if (!skb_queue_is_last(&tx->skbs, skb)) {
966 			hdr->frame_control |= morefrags;
967 			/*
968 			 * No multi-rate retries for fragmented frames, that
969 			 * would completely throw off the NAV at other STAs.
970 			 */
971 			info->control.rates[1].idx = -1;
972 			info->control.rates[2].idx = -1;
973 			info->control.rates[3].idx = -1;
974 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 4);
975 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
976 		} else {
977 			hdr->frame_control &= ~morefrags;
978 		}
979 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
980 		fragnum++;
981 	}
982 
983 	return TX_CONTINUE;
984 }
985 
986 static ieee80211_tx_result debug_noinline
987 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
988 {
989 	struct sk_buff *skb;
990 	int ac = -1;
991 
992 	if (!tx->sta)
993 		return TX_CONTINUE;
994 
995 	skb_queue_walk(&tx->skbs, skb) {
996 		ac = skb_get_queue_mapping(skb);
997 		tx->sta->tx_bytes[ac] += skb->len;
998 	}
999 	if (ac >= 0)
1000 		tx->sta->tx_packets[ac]++;
1001 
1002 	return TX_CONTINUE;
1003 }
1004 
1005 static ieee80211_tx_result debug_noinline
1006 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
1007 {
1008 	if (!tx->key)
1009 		return TX_CONTINUE;
1010 
1011 	switch (tx->key->conf.cipher) {
1012 	case WLAN_CIPHER_SUITE_WEP40:
1013 	case WLAN_CIPHER_SUITE_WEP104:
1014 		return ieee80211_crypto_wep_encrypt(tx);
1015 	case WLAN_CIPHER_SUITE_TKIP:
1016 		return ieee80211_crypto_tkip_encrypt(tx);
1017 	case WLAN_CIPHER_SUITE_CCMP:
1018 		return ieee80211_crypto_ccmp_encrypt(
1019 			tx, IEEE80211_CCMP_MIC_LEN);
1020 	case WLAN_CIPHER_SUITE_CCMP_256:
1021 		return ieee80211_crypto_ccmp_encrypt(
1022 			tx, IEEE80211_CCMP_256_MIC_LEN);
1023 	case WLAN_CIPHER_SUITE_AES_CMAC:
1024 		return ieee80211_crypto_aes_cmac_encrypt(tx);
1025 	case WLAN_CIPHER_SUITE_BIP_CMAC_256:
1026 		return ieee80211_crypto_aes_cmac_256_encrypt(tx);
1027 	case WLAN_CIPHER_SUITE_BIP_GMAC_128:
1028 	case WLAN_CIPHER_SUITE_BIP_GMAC_256:
1029 		return ieee80211_crypto_aes_gmac_encrypt(tx);
1030 	case WLAN_CIPHER_SUITE_GCMP:
1031 	case WLAN_CIPHER_SUITE_GCMP_256:
1032 		return ieee80211_crypto_gcmp_encrypt(tx);
1033 	default:
1034 		return ieee80211_crypto_hw_encrypt(tx);
1035 	}
1036 
1037 	return TX_DROP;
1038 }
1039 
1040 static ieee80211_tx_result debug_noinline
1041 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
1042 {
1043 	struct sk_buff *skb;
1044 	struct ieee80211_hdr *hdr;
1045 	int next_len;
1046 	bool group_addr;
1047 
1048 	skb_queue_walk(&tx->skbs, skb) {
1049 		hdr = (void *) skb->data;
1050 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
1051 			break; /* must not overwrite AID */
1052 		if (!skb_queue_is_last(&tx->skbs, skb)) {
1053 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
1054 			next_len = next->len;
1055 		} else
1056 			next_len = 0;
1057 		group_addr = is_multicast_ether_addr(hdr->addr1);
1058 
1059 		hdr->duration_id =
1060 			ieee80211_duration(tx, skb, group_addr, next_len);
1061 	}
1062 
1063 	return TX_CONTINUE;
1064 }
1065 
1066 /* actual transmit path */
1067 
1068 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1069 				  struct sk_buff *skb,
1070 				  struct ieee80211_tx_info *info,
1071 				  struct tid_ampdu_tx *tid_tx,
1072 				  int tid)
1073 {
1074 	bool queued = false;
1075 	bool reset_agg_timer = false;
1076 	struct sk_buff *purge_skb = NULL;
1077 
1078 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1079 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1080 		reset_agg_timer = true;
1081 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1082 		/*
1083 		 * nothing -- this aggregation session is being started
1084 		 * but that might still fail with the driver
1085 		 */
1086 	} else if (!tx->sta->sta.txq[tid]) {
1087 		spin_lock(&tx->sta->lock);
1088 		/*
1089 		 * Need to re-check now, because we may get here
1090 		 *
1091 		 *  1) in the window during which the setup is actually
1092 		 *     already done, but not marked yet because not all
1093 		 *     packets are spliced over to the driver pending
1094 		 *     queue yet -- if this happened we acquire the lock
1095 		 *     either before or after the splice happens, but
1096 		 *     need to recheck which of these cases happened.
1097 		 *
1098 		 *  2) during session teardown, if the OPERATIONAL bit
1099 		 *     was cleared due to the teardown but the pointer
1100 		 *     hasn't been assigned NULL yet (or we loaded it
1101 		 *     before it was assigned) -- in this case it may
1102 		 *     now be NULL which means we should just let the
1103 		 *     packet pass through because splicing the frames
1104 		 *     back is already done.
1105 		 */
1106 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1107 
1108 		if (!tid_tx) {
1109 			/* do nothing, let packet pass through */
1110 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1111 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1112 			reset_agg_timer = true;
1113 		} else {
1114 			queued = true;
1115 			info->control.vif = &tx->sdata->vif;
1116 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1117 			info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS |
1118 					IEEE80211_TX_CTL_NO_PS_BUFFER |
1119 					IEEE80211_TX_STATUS_EOSP;
1120 			__skb_queue_tail(&tid_tx->pending, skb);
1121 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1122 				purge_skb = __skb_dequeue(&tid_tx->pending);
1123 		}
1124 		spin_unlock(&tx->sta->lock);
1125 
1126 		if (purge_skb)
1127 			ieee80211_free_txskb(&tx->local->hw, purge_skb);
1128 	}
1129 
1130 	/* reset session timer */
1131 	if (reset_agg_timer && tid_tx->timeout)
1132 		tid_tx->last_tx = jiffies;
1133 
1134 	return queued;
1135 }
1136 
1137 /*
1138  * initialises @tx
1139  * pass %NULL for the station if unknown, a valid pointer if known
1140  * or an ERR_PTR() if the station is known not to exist
1141  */
1142 static ieee80211_tx_result
1143 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1144 		     struct ieee80211_tx_data *tx,
1145 		     struct sta_info *sta, struct sk_buff *skb)
1146 {
1147 	struct ieee80211_local *local = sdata->local;
1148 	struct ieee80211_hdr *hdr;
1149 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1150 	int tid;
1151 	u8 *qc;
1152 
1153 	memset(tx, 0, sizeof(*tx));
1154 	tx->skb = skb;
1155 	tx->local = local;
1156 	tx->sdata = sdata;
1157 	__skb_queue_head_init(&tx->skbs);
1158 
1159 	/*
1160 	 * If this flag is set to true anywhere, and we get here,
1161 	 * we are doing the needed processing, so remove the flag
1162 	 * now.
1163 	 */
1164 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1165 
1166 	hdr = (struct ieee80211_hdr *) skb->data;
1167 
1168 	if (likely(sta)) {
1169 		if (!IS_ERR(sta))
1170 			tx->sta = sta;
1171 	} else {
1172 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1173 			tx->sta = rcu_dereference(sdata->u.vlan.sta);
1174 			if (!tx->sta && sdata->wdev.use_4addr)
1175 				return TX_DROP;
1176 		} else if (info->flags & (IEEE80211_TX_INTFL_NL80211_FRAME_TX |
1177 					  IEEE80211_TX_CTL_INJECTED) ||
1178 			   tx->sdata->control_port_protocol == tx->skb->protocol) {
1179 			tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1180 		}
1181 		if (!tx->sta && !is_multicast_ether_addr(hdr->addr1))
1182 			tx->sta = sta_info_get(sdata, hdr->addr1);
1183 	}
1184 
1185 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1186 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1187 	    ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) &&
1188 	    !ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW)) {
1189 		struct tid_ampdu_tx *tid_tx;
1190 
1191 		qc = ieee80211_get_qos_ctl(hdr);
1192 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1193 
1194 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1195 		if (tid_tx) {
1196 			bool queued;
1197 
1198 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1199 						       tid_tx, tid);
1200 
1201 			if (unlikely(queued))
1202 				return TX_QUEUED;
1203 		}
1204 	}
1205 
1206 	if (is_multicast_ether_addr(hdr->addr1)) {
1207 		tx->flags &= ~IEEE80211_TX_UNICAST;
1208 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1209 	} else
1210 		tx->flags |= IEEE80211_TX_UNICAST;
1211 
1212 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1213 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1214 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1215 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1216 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1217 	}
1218 
1219 	if (!tx->sta)
1220 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1221 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1222 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1223 
1224 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1225 
1226 	return TX_CONTINUE;
1227 }
1228 
1229 static void ieee80211_drv_tx(struct ieee80211_local *local,
1230 			     struct ieee80211_vif *vif,
1231 			     struct ieee80211_sta *pubsta,
1232 			     struct sk_buff *skb)
1233 {
1234 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1235 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1236 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1237 	struct ieee80211_tx_control control = {
1238 		.sta = pubsta,
1239 	};
1240 	struct ieee80211_txq *txq = NULL;
1241 	struct txq_info *txqi;
1242 	u8 ac;
1243 
1244 	if (info->control.flags & IEEE80211_TX_CTRL_PS_RESPONSE)
1245 		goto tx_normal;
1246 
1247 	if (!ieee80211_is_data(hdr->frame_control))
1248 		goto tx_normal;
1249 
1250 	if (pubsta) {
1251 		u8 tid = skb->priority & IEEE80211_QOS_CTL_TID_MASK;
1252 
1253 		txq = pubsta->txq[tid];
1254 	} else if (vif) {
1255 		txq = vif->txq;
1256 	}
1257 
1258 	if (!txq)
1259 		goto tx_normal;
1260 
1261 	ac = txq->ac;
1262 	txqi = to_txq_info(txq);
1263 	atomic_inc(&sdata->txqs_len[ac]);
1264 	if (atomic_read(&sdata->txqs_len[ac]) >= local->hw.txq_ac_max_pending)
1265 		netif_stop_subqueue(sdata->dev, ac);
1266 
1267 	skb_queue_tail(&txqi->queue, skb);
1268 	drv_wake_tx_queue(local, txqi);
1269 
1270 	return;
1271 
1272 tx_normal:
1273 	drv_tx(local, &control, skb);
1274 }
1275 
1276 struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
1277 				     struct ieee80211_txq *txq)
1278 {
1279 	struct ieee80211_local *local = hw_to_local(hw);
1280 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(txq->vif);
1281 	struct txq_info *txqi = container_of(txq, struct txq_info, txq);
1282 	struct ieee80211_hdr *hdr;
1283 	struct sk_buff *skb = NULL;
1284 	u8 ac = txq->ac;
1285 
1286 	spin_lock_bh(&txqi->queue.lock);
1287 
1288 	if (test_bit(IEEE80211_TXQ_STOP, &txqi->flags))
1289 		goto out;
1290 
1291 	skb = __skb_dequeue(&txqi->queue);
1292 	if (!skb)
1293 		goto out;
1294 
1295 	atomic_dec(&sdata->txqs_len[ac]);
1296 	if (__netif_subqueue_stopped(sdata->dev, ac))
1297 		ieee80211_propagate_queue_wake(local, sdata->vif.hw_queue[ac]);
1298 
1299 	hdr = (struct ieee80211_hdr *)skb->data;
1300 	if (txq->sta && ieee80211_is_data_qos(hdr->frame_control)) {
1301 		struct sta_info *sta = container_of(txq->sta, struct sta_info,
1302 						    sta);
1303 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1304 
1305 		hdr->seq_ctrl = ieee80211_tx_next_seq(sta, txq->tid);
1306 		if (test_bit(IEEE80211_TXQ_AMPDU, &txqi->flags))
1307 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1308 		else
1309 			info->flags &= ~IEEE80211_TX_CTL_AMPDU;
1310 	}
1311 
1312 out:
1313 	spin_unlock_bh(&txqi->queue.lock);
1314 
1315 	return skb;
1316 }
1317 EXPORT_SYMBOL(ieee80211_tx_dequeue);
1318 
1319 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1320 			       struct ieee80211_vif *vif,
1321 			       struct ieee80211_sta *sta,
1322 			       struct sk_buff_head *skbs,
1323 			       bool txpending)
1324 {
1325 	struct sk_buff *skb, *tmp;
1326 	unsigned long flags;
1327 
1328 	skb_queue_walk_safe(skbs, skb, tmp) {
1329 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1330 		int q = info->hw_queue;
1331 
1332 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1333 		if (WARN_ON_ONCE(q >= local->hw.queues)) {
1334 			__skb_unlink(skb, skbs);
1335 			ieee80211_free_txskb(&local->hw, skb);
1336 			continue;
1337 		}
1338 #endif
1339 
1340 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1341 		if (local->queue_stop_reasons[q] ||
1342 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1343 			if (unlikely(info->flags &
1344 				     IEEE80211_TX_INTFL_OFFCHAN_TX_OK)) {
1345 				if (local->queue_stop_reasons[q] &
1346 				    ~BIT(IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL)) {
1347 					/*
1348 					 * Drop off-channel frames if queues
1349 					 * are stopped for any reason other
1350 					 * than off-channel operation. Never
1351 					 * queue them.
1352 					 */
1353 					spin_unlock_irqrestore(
1354 						&local->queue_stop_reason_lock,
1355 						flags);
1356 					ieee80211_purge_tx_queue(&local->hw,
1357 								 skbs);
1358 					return true;
1359 				}
1360 			} else {
1361 
1362 				/*
1363 				 * Since queue is stopped, queue up frames for
1364 				 * later transmission from the tx-pending
1365 				 * tasklet when the queue is woken again.
1366 				 */
1367 				if (txpending)
1368 					skb_queue_splice_init(skbs,
1369 							      &local->pending[q]);
1370 				else
1371 					skb_queue_splice_tail_init(skbs,
1372 								   &local->pending[q]);
1373 
1374 				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1375 						       flags);
1376 				return false;
1377 			}
1378 		}
1379 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1380 
1381 		info->control.vif = vif;
1382 
1383 		__skb_unlink(skb, skbs);
1384 		ieee80211_drv_tx(local, vif, sta, skb);
1385 	}
1386 
1387 	return true;
1388 }
1389 
1390 /*
1391  * Returns false if the frame couldn't be transmitted but was queued instead.
1392  */
1393 static bool __ieee80211_tx(struct ieee80211_local *local,
1394 			   struct sk_buff_head *skbs, int led_len,
1395 			   struct sta_info *sta, bool txpending)
1396 {
1397 	struct ieee80211_tx_info *info;
1398 	struct ieee80211_sub_if_data *sdata;
1399 	struct ieee80211_vif *vif;
1400 	struct ieee80211_sta *pubsta;
1401 	struct sk_buff *skb;
1402 	bool result = true;
1403 	__le16 fc;
1404 
1405 	if (WARN_ON(skb_queue_empty(skbs)))
1406 		return true;
1407 
1408 	skb = skb_peek(skbs);
1409 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1410 	info = IEEE80211_SKB_CB(skb);
1411 	sdata = vif_to_sdata(info->control.vif);
1412 	if (sta && !sta->uploaded)
1413 		sta = NULL;
1414 
1415 	if (sta)
1416 		pubsta = &sta->sta;
1417 	else
1418 		pubsta = NULL;
1419 
1420 	switch (sdata->vif.type) {
1421 	case NL80211_IFTYPE_MONITOR:
1422 		if (sdata->u.mntr_flags & MONITOR_FLAG_ACTIVE) {
1423 			vif = &sdata->vif;
1424 			break;
1425 		}
1426 		sdata = rcu_dereference(local->monitor_sdata);
1427 		if (sdata) {
1428 			vif = &sdata->vif;
1429 			info->hw_queue =
1430 				vif->hw_queue[skb_get_queue_mapping(skb)];
1431 		} else if (ieee80211_hw_check(&local->hw, QUEUE_CONTROL)) {
1432 			dev_kfree_skb(skb);
1433 			return true;
1434 		} else
1435 			vif = NULL;
1436 		break;
1437 	case NL80211_IFTYPE_AP_VLAN:
1438 		sdata = container_of(sdata->bss,
1439 				     struct ieee80211_sub_if_data, u.ap);
1440 		/* fall through */
1441 	default:
1442 		vif = &sdata->vif;
1443 		break;
1444 	}
1445 
1446 	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1447 				    txpending);
1448 
1449 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1450 
1451 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1452 
1453 	return result;
1454 }
1455 
1456 /*
1457  * Invoke TX handlers, return 0 on success and non-zero if the
1458  * frame was dropped or queued.
1459  */
1460 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1461 {
1462 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1463 	ieee80211_tx_result res = TX_DROP;
1464 
1465 #define CALL_TXH(txh) \
1466 	do {				\
1467 		res = txh(tx);		\
1468 		if (res != TX_CONTINUE)	\
1469 			goto txh_done;	\
1470 	} while (0)
1471 
1472 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1473 	CALL_TXH(ieee80211_tx_h_check_assoc);
1474 	CALL_TXH(ieee80211_tx_h_ps_buf);
1475 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1476 	CALL_TXH(ieee80211_tx_h_select_key);
1477 	if (!ieee80211_hw_check(&tx->local->hw, HAS_RATE_CONTROL))
1478 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1479 
1480 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1481 		__skb_queue_tail(&tx->skbs, tx->skb);
1482 		tx->skb = NULL;
1483 		goto txh_done;
1484 	}
1485 
1486 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1487 	CALL_TXH(ieee80211_tx_h_sequence);
1488 	CALL_TXH(ieee80211_tx_h_fragment);
1489 	/* handlers after fragment must be aware of tx info fragmentation! */
1490 	CALL_TXH(ieee80211_tx_h_stats);
1491 	CALL_TXH(ieee80211_tx_h_encrypt);
1492 	if (!ieee80211_hw_check(&tx->local->hw, HAS_RATE_CONTROL))
1493 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1494 #undef CALL_TXH
1495 
1496  txh_done:
1497 	if (unlikely(res == TX_DROP)) {
1498 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1499 		if (tx->skb)
1500 			ieee80211_free_txskb(&tx->local->hw, tx->skb);
1501 		else
1502 			ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
1503 		return -1;
1504 	} else if (unlikely(res == TX_QUEUED)) {
1505 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1506 		return -1;
1507 	}
1508 
1509 	return 0;
1510 }
1511 
1512 bool ieee80211_tx_prepare_skb(struct ieee80211_hw *hw,
1513 			      struct ieee80211_vif *vif, struct sk_buff *skb,
1514 			      int band, struct ieee80211_sta **sta)
1515 {
1516 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
1517 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1518 	struct ieee80211_tx_data tx;
1519 	struct sk_buff *skb2;
1520 
1521 	if (ieee80211_tx_prepare(sdata, &tx, NULL, skb) == TX_DROP)
1522 		return false;
1523 
1524 	info->band = band;
1525 	info->control.vif = vif;
1526 	info->hw_queue = vif->hw_queue[skb_get_queue_mapping(skb)];
1527 
1528 	if (invoke_tx_handlers(&tx))
1529 		return false;
1530 
1531 	if (sta) {
1532 		if (tx.sta)
1533 			*sta = &tx.sta->sta;
1534 		else
1535 			*sta = NULL;
1536 	}
1537 
1538 	/* this function isn't suitable for fragmented data frames */
1539 	skb2 = __skb_dequeue(&tx.skbs);
1540 	if (WARN_ON(skb2 != skb || !skb_queue_empty(&tx.skbs))) {
1541 		ieee80211_free_txskb(hw, skb2);
1542 		ieee80211_purge_tx_queue(hw, &tx.skbs);
1543 		return false;
1544 	}
1545 
1546 	return true;
1547 }
1548 EXPORT_SYMBOL(ieee80211_tx_prepare_skb);
1549 
1550 /*
1551  * Returns false if the frame couldn't be transmitted but was queued instead.
1552  */
1553 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1554 			 struct sta_info *sta, struct sk_buff *skb,
1555 			 bool txpending)
1556 {
1557 	struct ieee80211_local *local = sdata->local;
1558 	struct ieee80211_tx_data tx;
1559 	ieee80211_tx_result res_prepare;
1560 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1561 	bool result = true;
1562 	int led_len;
1563 
1564 	if (unlikely(skb->len < 10)) {
1565 		dev_kfree_skb(skb);
1566 		return true;
1567 	}
1568 
1569 	/* initialises tx */
1570 	led_len = skb->len;
1571 	res_prepare = ieee80211_tx_prepare(sdata, &tx, sta, skb);
1572 
1573 	if (unlikely(res_prepare == TX_DROP)) {
1574 		ieee80211_free_txskb(&local->hw, skb);
1575 		return true;
1576 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1577 		return true;
1578 	}
1579 
1580 	/* set up hw_queue value early */
1581 	if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
1582 	    !ieee80211_hw_check(&local->hw, QUEUE_CONTROL))
1583 		info->hw_queue =
1584 			sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
1585 
1586 	if (!invoke_tx_handlers(&tx))
1587 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1588 					tx.sta, txpending);
1589 
1590 	return result;
1591 }
1592 
1593 /* device xmit handlers */
1594 
1595 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1596 				struct sk_buff *skb,
1597 				int head_need, bool may_encrypt)
1598 {
1599 	struct ieee80211_local *local = sdata->local;
1600 	int tail_need = 0;
1601 
1602 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1603 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1604 		tail_need -= skb_tailroom(skb);
1605 		tail_need = max_t(int, tail_need, 0);
1606 	}
1607 
1608 	if (skb_cloned(skb) &&
1609 	    (!ieee80211_hw_check(&local->hw, SUPPORTS_CLONED_SKBS) ||
1610 	     !skb_clone_writable(skb, ETH_HLEN) ||
1611 	     (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt)))
1612 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1613 	else if (head_need || tail_need)
1614 		I802_DEBUG_INC(local->tx_expand_skb_head);
1615 	else
1616 		return 0;
1617 
1618 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1619 		wiphy_debug(local->hw.wiphy,
1620 			    "failed to reallocate TX buffer\n");
1621 		return -ENOMEM;
1622 	}
1623 
1624 	return 0;
1625 }
1626 
1627 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata,
1628 		    struct sta_info *sta, struct sk_buff *skb)
1629 {
1630 	struct ieee80211_local *local = sdata->local;
1631 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1632 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1633 	int headroom;
1634 	bool may_encrypt;
1635 
1636 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1637 
1638 	headroom = local->tx_headroom;
1639 	if (may_encrypt)
1640 		headroom += sdata->encrypt_headroom;
1641 	headroom -= skb_headroom(skb);
1642 	headroom = max_t(int, 0, headroom);
1643 
1644 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1645 		ieee80211_free_txskb(&local->hw, skb);
1646 		return;
1647 	}
1648 
1649 	hdr = (struct ieee80211_hdr *) skb->data;
1650 	info->control.vif = &sdata->vif;
1651 
1652 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1653 		if (ieee80211_is_data(hdr->frame_control) &&
1654 		    is_unicast_ether_addr(hdr->addr1)) {
1655 			if (mesh_nexthop_resolve(sdata, skb))
1656 				return; /* skb queued: don't free */
1657 		} else {
1658 			ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
1659 		}
1660 	}
1661 
1662 	ieee80211_set_qos_hdr(sdata, skb);
1663 	ieee80211_tx(sdata, sta, skb, false);
1664 }
1665 
1666 static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
1667 {
1668 	struct ieee80211_radiotap_iterator iterator;
1669 	struct ieee80211_radiotap_header *rthdr =
1670 		(struct ieee80211_radiotap_header *) skb->data;
1671 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1672 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1673 						   NULL);
1674 	u16 txflags;
1675 
1676 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1677 		       IEEE80211_TX_CTL_DONTFRAG;
1678 
1679 	/*
1680 	 * for every radiotap entry that is present
1681 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1682 	 * entries present, or -EINVAL on error)
1683 	 */
1684 
1685 	while (!ret) {
1686 		ret = ieee80211_radiotap_iterator_next(&iterator);
1687 
1688 		if (ret)
1689 			continue;
1690 
1691 		/* see if this argument is something we can use */
1692 		switch (iterator.this_arg_index) {
1693 		/*
1694 		 * You must take care when dereferencing iterator.this_arg
1695 		 * for multibyte types... the pointer is not aligned.  Use
1696 		 * get_unaligned((type *)iterator.this_arg) to dereference
1697 		 * iterator.this_arg for type "type" safely on all arches.
1698 		*/
1699 		case IEEE80211_RADIOTAP_FLAGS:
1700 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1701 				/*
1702 				 * this indicates that the skb we have been
1703 				 * handed has the 32-bit FCS CRC at the end...
1704 				 * we should react to that by snipping it off
1705 				 * because it will be recomputed and added
1706 				 * on transmission
1707 				 */
1708 				if (skb->len < (iterator._max_length + FCS_LEN))
1709 					return false;
1710 
1711 				skb_trim(skb, skb->len - FCS_LEN);
1712 			}
1713 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1714 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1715 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1716 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1717 			break;
1718 
1719 		case IEEE80211_RADIOTAP_TX_FLAGS:
1720 			txflags = get_unaligned_le16(iterator.this_arg);
1721 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1722 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1723 			break;
1724 
1725 		/*
1726 		 * Please update the file
1727 		 * Documentation/networking/mac80211-injection.txt
1728 		 * when parsing new fields here.
1729 		 */
1730 
1731 		default:
1732 			break;
1733 		}
1734 	}
1735 
1736 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1737 		return false;
1738 
1739 	/*
1740 	 * remove the radiotap header
1741 	 * iterator->_max_length was sanity-checked against
1742 	 * skb->len by iterator init
1743 	 */
1744 	skb_pull(skb, iterator._max_length);
1745 
1746 	return true;
1747 }
1748 
1749 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1750 					 struct net_device *dev)
1751 {
1752 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1753 	struct ieee80211_chanctx_conf *chanctx_conf;
1754 	struct ieee80211_radiotap_header *prthdr =
1755 		(struct ieee80211_radiotap_header *)skb->data;
1756 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1757 	struct ieee80211_hdr *hdr;
1758 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1759 	struct cfg80211_chan_def *chandef;
1760 	u16 len_rthdr;
1761 	int hdrlen;
1762 
1763 	/* check for not even having the fixed radiotap header part */
1764 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1765 		goto fail; /* too short to be possibly valid */
1766 
1767 	/* is it a header version we can trust to find length from? */
1768 	if (unlikely(prthdr->it_version))
1769 		goto fail; /* only version 0 is supported */
1770 
1771 	/* then there must be a radiotap header with a length we can use */
1772 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1773 
1774 	/* does the skb contain enough to deliver on the alleged length? */
1775 	if (unlikely(skb->len < len_rthdr))
1776 		goto fail; /* skb too short for claimed rt header extent */
1777 
1778 	/*
1779 	 * fix up the pointers accounting for the radiotap
1780 	 * header still being in there.  We are being given
1781 	 * a precooked IEEE80211 header so no need for
1782 	 * normal processing
1783 	 */
1784 	skb_set_mac_header(skb, len_rthdr);
1785 	/*
1786 	 * these are just fixed to the end of the rt area since we
1787 	 * don't have any better information and at this point, nobody cares
1788 	 */
1789 	skb_set_network_header(skb, len_rthdr);
1790 	skb_set_transport_header(skb, len_rthdr);
1791 
1792 	if (skb->len < len_rthdr + 2)
1793 		goto fail;
1794 
1795 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1796 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1797 
1798 	if (skb->len < len_rthdr + hdrlen)
1799 		goto fail;
1800 
1801 	/*
1802 	 * Initialize skb->protocol if the injected frame is a data frame
1803 	 * carrying a rfc1042 header
1804 	 */
1805 	if (ieee80211_is_data(hdr->frame_control) &&
1806 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1807 		u8 *payload = (u8 *)hdr + hdrlen;
1808 
1809 		if (ether_addr_equal(payload, rfc1042_header))
1810 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1811 						    payload[7]);
1812 	}
1813 
1814 	memset(info, 0, sizeof(*info));
1815 
1816 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1817 		      IEEE80211_TX_CTL_INJECTED;
1818 
1819 	/* process and remove the injection radiotap header */
1820 	if (!ieee80211_parse_tx_radiotap(skb))
1821 		goto fail;
1822 
1823 	rcu_read_lock();
1824 
1825 	/*
1826 	 * We process outgoing injected frames that have a local address
1827 	 * we handle as though they are non-injected frames.
1828 	 * This code here isn't entirely correct, the local MAC address
1829 	 * isn't always enough to find the interface to use; for proper
1830 	 * VLAN/WDS support we will need a different mechanism (which
1831 	 * likely isn't going to be monitor interfaces).
1832 	 */
1833 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1834 
1835 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1836 		if (!ieee80211_sdata_running(tmp_sdata))
1837 			continue;
1838 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1839 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1840 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1841 			continue;
1842 		if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
1843 			sdata = tmp_sdata;
1844 			break;
1845 		}
1846 	}
1847 
1848 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1849 	if (!chanctx_conf) {
1850 		tmp_sdata = rcu_dereference(local->monitor_sdata);
1851 		if (tmp_sdata)
1852 			chanctx_conf =
1853 				rcu_dereference(tmp_sdata->vif.chanctx_conf);
1854 	}
1855 
1856 	if (chanctx_conf)
1857 		chandef = &chanctx_conf->def;
1858 	else if (!local->use_chanctx)
1859 		chandef = &local->_oper_chandef;
1860 	else
1861 		goto fail_rcu;
1862 
1863 	/*
1864 	 * Frame injection is not allowed if beaconing is not allowed
1865 	 * or if we need radar detection. Beaconing is usually not allowed when
1866 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1867 	 * Passive scan is also used in world regulatory domains where
1868 	 * your country is not known and as such it should be treated as
1869 	 * NO TX unless the channel is explicitly allowed in which case
1870 	 * your current regulatory domain would not have the passive scan
1871 	 * flag.
1872 	 *
1873 	 * Since AP mode uses monitor interfaces to inject/TX management
1874 	 * frames we can make AP mode the exception to this rule once it
1875 	 * supports radar detection as its implementation can deal with
1876 	 * radar detection by itself. We can do that later by adding a
1877 	 * monitor flag interfaces used for AP support.
1878 	 */
1879 	if (!cfg80211_reg_can_beacon(local->hw.wiphy, chandef,
1880 				     sdata->vif.type))
1881 		goto fail_rcu;
1882 
1883 	info->band = chandef->chan->band;
1884 	ieee80211_xmit(sdata, NULL, skb);
1885 	rcu_read_unlock();
1886 
1887 	return NETDEV_TX_OK;
1888 
1889 fail_rcu:
1890 	rcu_read_unlock();
1891 fail:
1892 	dev_kfree_skb(skb);
1893 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1894 }
1895 
1896 static inline bool ieee80211_is_tdls_setup(struct sk_buff *skb)
1897 {
1898 	u16 ethertype = (skb->data[12] << 8) | skb->data[13];
1899 
1900 	return ethertype == ETH_P_TDLS &&
1901 	       skb->len > 14 &&
1902 	       skb->data[14] == WLAN_TDLS_SNAP_RFTYPE;
1903 }
1904 
1905 static int ieee80211_lookup_ra_sta(struct ieee80211_sub_if_data *sdata,
1906 				   struct sk_buff *skb,
1907 				   struct sta_info **sta_out)
1908 {
1909 	struct sta_info *sta;
1910 
1911 	switch (sdata->vif.type) {
1912 	case NL80211_IFTYPE_AP_VLAN:
1913 		sta = rcu_dereference(sdata->u.vlan.sta);
1914 		if (sta) {
1915 			*sta_out = sta;
1916 			return 0;
1917 		} else if (sdata->wdev.use_4addr) {
1918 			return -ENOLINK;
1919 		}
1920 		/* fall through */
1921 	case NL80211_IFTYPE_AP:
1922 	case NL80211_IFTYPE_OCB:
1923 	case NL80211_IFTYPE_ADHOC:
1924 		if (is_multicast_ether_addr(skb->data)) {
1925 			*sta_out = ERR_PTR(-ENOENT);
1926 			return 0;
1927 		}
1928 		sta = sta_info_get_bss(sdata, skb->data);
1929 		break;
1930 	case NL80211_IFTYPE_WDS:
1931 		sta = sta_info_get(sdata, sdata->u.wds.remote_addr);
1932 		break;
1933 #ifdef CONFIG_MAC80211_MESH
1934 	case NL80211_IFTYPE_MESH_POINT:
1935 		/* determined much later */
1936 		*sta_out = NULL;
1937 		return 0;
1938 #endif
1939 	case NL80211_IFTYPE_STATION:
1940 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
1941 			sta = sta_info_get(sdata, skb->data);
1942 			if (sta) {
1943 				bool tdls_peer, tdls_auth;
1944 
1945 				tdls_peer = test_sta_flag(sta,
1946 							  WLAN_STA_TDLS_PEER);
1947 				tdls_auth = test_sta_flag(sta,
1948 						WLAN_STA_TDLS_PEER_AUTH);
1949 
1950 				if (tdls_peer && tdls_auth) {
1951 					*sta_out = sta;
1952 					return 0;
1953 				}
1954 
1955 				/*
1956 				 * TDLS link during setup - throw out frames to
1957 				 * peer. Allow TDLS-setup frames to unauthorized
1958 				 * peers for the special case of a link teardown
1959 				 * after a TDLS sta is removed due to being
1960 				 * unreachable.
1961 				 */
1962 				if (tdls_peer && !tdls_auth &&
1963 				    !ieee80211_is_tdls_setup(skb))
1964 					return -EINVAL;
1965 			}
1966 
1967 		}
1968 
1969 		sta = sta_info_get(sdata, sdata->u.mgd.bssid);
1970 		if (!sta)
1971 			return -ENOLINK;
1972 		break;
1973 	default:
1974 		return -EINVAL;
1975 	}
1976 
1977 	*sta_out = sta ?: ERR_PTR(-ENOENT);
1978 	return 0;
1979 }
1980 
1981 /**
1982  * ieee80211_build_hdr - build 802.11 header in the given frame
1983  * @sdata: virtual interface to build the header for
1984  * @skb: the skb to build the header in
1985  * @info_flags: skb flags to set
1986  *
1987  * This function takes the skb with 802.3 header and reformats the header to
1988  * the appropriate IEEE 802.11 header based on which interface the packet is
1989  * being transmitted on.
1990  *
1991  * Note that this function also takes care of the TX status request and
1992  * potential unsharing of the SKB - this needs to be interleaved with the
1993  * header building.
1994  *
1995  * The function requires the read-side RCU lock held
1996  *
1997  * Returns: the (possibly reallocated) skb or an ERR_PTR() code
1998  */
1999 static struct sk_buff *ieee80211_build_hdr(struct ieee80211_sub_if_data *sdata,
2000 					   struct sk_buff *skb, u32 info_flags,
2001 					   struct sta_info *sta)
2002 {
2003 	struct ieee80211_local *local = sdata->local;
2004 	struct ieee80211_tx_info *info;
2005 	int head_need;
2006 	u16 ethertype, hdrlen,  meshhdrlen = 0;
2007 	__le16 fc;
2008 	struct ieee80211_hdr hdr;
2009 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
2010 	struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
2011 	const u8 *encaps_data;
2012 	int encaps_len, skip_header_bytes;
2013 	int nh_pos, h_pos;
2014 	bool wme_sta = false, authorized = false;
2015 	bool tdls_peer;
2016 	bool multicast;
2017 	u16 info_id = 0;
2018 	struct ieee80211_chanctx_conf *chanctx_conf;
2019 	struct ieee80211_sub_if_data *ap_sdata;
2020 	enum ieee80211_band band;
2021 	int ret;
2022 
2023 	if (IS_ERR(sta))
2024 		sta = NULL;
2025 
2026 	/* convert Ethernet header to proper 802.11 header (based on
2027 	 * operation mode) */
2028 	ethertype = (skb->data[12] << 8) | skb->data[13];
2029 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
2030 
2031 	switch (sdata->vif.type) {
2032 	case NL80211_IFTYPE_AP_VLAN:
2033 		if (sdata->wdev.use_4addr) {
2034 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
2035 			/* RA TA DA SA */
2036 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
2037 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2038 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2039 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2040 			hdrlen = 30;
2041 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
2042 			wme_sta = sta->sta.wme;
2043 		}
2044 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
2045 					u.ap);
2046 		chanctx_conf = rcu_dereference(ap_sdata->vif.chanctx_conf);
2047 		if (!chanctx_conf) {
2048 			ret = -ENOTCONN;
2049 			goto free;
2050 		}
2051 		band = chanctx_conf->def.chan->band;
2052 		if (sdata->wdev.use_4addr)
2053 			break;
2054 		/* fall through */
2055 	case NL80211_IFTYPE_AP:
2056 		if (sdata->vif.type == NL80211_IFTYPE_AP)
2057 			chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2058 		if (!chanctx_conf) {
2059 			ret = -ENOTCONN;
2060 			goto free;
2061 		}
2062 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
2063 		/* DA BSSID SA */
2064 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2065 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2066 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
2067 		hdrlen = 24;
2068 		band = chanctx_conf->def.chan->band;
2069 		break;
2070 	case NL80211_IFTYPE_WDS:
2071 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
2072 		/* RA TA DA SA */
2073 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
2074 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2075 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
2076 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2077 		hdrlen = 30;
2078 		/*
2079 		 * This is the exception! WDS style interfaces are prohibited
2080 		 * when channel contexts are in used so this must be valid
2081 		 */
2082 		band = local->hw.conf.chandef.chan->band;
2083 		break;
2084 #ifdef CONFIG_MAC80211_MESH
2085 	case NL80211_IFTYPE_MESH_POINT:
2086 		if (!is_multicast_ether_addr(skb->data)) {
2087 			struct sta_info *next_hop;
2088 			bool mpp_lookup = true;
2089 
2090 			mpath = mesh_path_lookup(sdata, skb->data);
2091 			if (mpath) {
2092 				mpp_lookup = false;
2093 				next_hop = rcu_dereference(mpath->next_hop);
2094 				if (!next_hop ||
2095 				    !(mpath->flags & (MESH_PATH_ACTIVE |
2096 						      MESH_PATH_RESOLVING)))
2097 					mpp_lookup = true;
2098 			}
2099 
2100 			if (mpp_lookup)
2101 				mppath = mpp_path_lookup(sdata, skb->data);
2102 
2103 			if (mppath && mpath)
2104 				mesh_path_del(mpath->sdata, mpath->dst);
2105 		}
2106 
2107 		/*
2108 		 * Use address extension if it is a packet from
2109 		 * another interface or if we know the destination
2110 		 * is being proxied by a portal (i.e. portal address
2111 		 * differs from proxied address)
2112 		 */
2113 		if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
2114 		    !(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
2115 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
2116 					skb->data, skb->data + ETH_ALEN);
2117 			meshhdrlen = ieee80211_new_mesh_header(sdata, &mesh_hdr,
2118 							       NULL, NULL);
2119 		} else {
2120 			/* DS -> MBSS (802.11-2012 13.11.3.3).
2121 			 * For unicast with unknown forwarding information,
2122 			 * destination might be in the MBSS or if that fails
2123 			 * forwarded to another mesh gate. In either case
2124 			 * resolution will be handled in ieee80211_xmit(), so
2125 			 * leave the original DA. This also works for mcast */
2126 			const u8 *mesh_da = skb->data;
2127 
2128 			if (mppath)
2129 				mesh_da = mppath->mpp;
2130 			else if (mpath)
2131 				mesh_da = mpath->dst;
2132 
2133 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
2134 					mesh_da, sdata->vif.addr);
2135 			if (is_multicast_ether_addr(mesh_da))
2136 				/* DA TA mSA AE:SA */
2137 				meshhdrlen = ieee80211_new_mesh_header(
2138 						sdata, &mesh_hdr,
2139 						skb->data + ETH_ALEN, NULL);
2140 			else
2141 				/* RA TA mDA mSA AE:DA SA */
2142 				meshhdrlen = ieee80211_new_mesh_header(
2143 						sdata, &mesh_hdr, skb->data,
2144 						skb->data + ETH_ALEN);
2145 
2146 		}
2147 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2148 		if (!chanctx_conf) {
2149 			ret = -ENOTCONN;
2150 			goto free;
2151 		}
2152 		band = chanctx_conf->def.chan->band;
2153 		break;
2154 #endif
2155 	case NL80211_IFTYPE_STATION:
2156 		/* we already did checks when looking up the RA STA */
2157 		tdls_peer = test_sta_flag(sta, WLAN_STA_TDLS_PEER);
2158 
2159 		if (tdls_peer) {
2160 			/* DA SA BSSID */
2161 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
2162 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2163 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
2164 			hdrlen = 24;
2165 		}  else if (sdata->u.mgd.use_4addr &&
2166 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
2167 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2168 					  IEEE80211_FCTL_TODS);
2169 			/* RA TA DA SA */
2170 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
2171 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
2172 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2173 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
2174 			hdrlen = 30;
2175 		} else {
2176 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
2177 			/* BSSID SA DA */
2178 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
2179 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2180 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
2181 			hdrlen = 24;
2182 		}
2183 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2184 		if (!chanctx_conf) {
2185 			ret = -ENOTCONN;
2186 			goto free;
2187 		}
2188 		band = chanctx_conf->def.chan->band;
2189 		break;
2190 	case NL80211_IFTYPE_OCB:
2191 		/* DA SA BSSID */
2192 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2193 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2194 		eth_broadcast_addr(hdr.addr3);
2195 		hdrlen = 24;
2196 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2197 		if (!chanctx_conf) {
2198 			ret = -ENOTCONN;
2199 			goto free;
2200 		}
2201 		band = chanctx_conf->def.chan->band;
2202 		break;
2203 	case NL80211_IFTYPE_ADHOC:
2204 		/* DA SA BSSID */
2205 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
2206 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
2207 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
2208 		hdrlen = 24;
2209 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2210 		if (!chanctx_conf) {
2211 			ret = -ENOTCONN;
2212 			goto free;
2213 		}
2214 		band = chanctx_conf->def.chan->band;
2215 		break;
2216 	default:
2217 		ret = -EINVAL;
2218 		goto free;
2219 	}
2220 
2221 	multicast = is_multicast_ether_addr(hdr.addr1);
2222 
2223 	/* sta is always NULL for mesh */
2224 	if (sta) {
2225 		authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
2226 		wme_sta = sta->sta.wme;
2227 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2228 		/* For mesh, the use of the QoS header is mandatory */
2229 		wme_sta = true;
2230 	}
2231 
2232 	/* receiver does QoS (which also means we do) use it */
2233 	if (wme_sta) {
2234 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2235 		hdrlen += 2;
2236 	}
2237 
2238 	/*
2239 	 * Drop unicast frames to unauthorised stations unless they are
2240 	 * EAPOL frames from the local station.
2241 	 */
2242 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
2243 		     (sdata->vif.type != NL80211_IFTYPE_OCB) &&
2244 		     !multicast && !authorized &&
2245 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
2246 		      !ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
2247 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
2248 		net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
2249 				    sdata->name, hdr.addr1);
2250 #endif
2251 
2252 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
2253 
2254 		ret = -EPERM;
2255 		goto free;
2256 	}
2257 
2258 	if (unlikely(!multicast && skb->sk &&
2259 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
2260 		struct sk_buff *ack_skb = skb_clone_sk(skb);
2261 
2262 		if (ack_skb) {
2263 			unsigned long flags;
2264 			int id;
2265 
2266 			spin_lock_irqsave(&local->ack_status_lock, flags);
2267 			id = idr_alloc(&local->ack_status_frames, ack_skb,
2268 				       1, 0x10000, GFP_ATOMIC);
2269 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
2270 
2271 			if (id >= 0) {
2272 				info_id = id;
2273 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
2274 			} else {
2275 				kfree_skb(ack_skb);
2276 			}
2277 		}
2278 	}
2279 
2280 	/*
2281 	 * If the skb is shared we need to obtain our own copy.
2282 	 */
2283 	if (skb_shared(skb)) {
2284 		struct sk_buff *tmp_skb = skb;
2285 
2286 		/* can't happen -- skb is a clone if info_id != 0 */
2287 		WARN_ON(info_id);
2288 
2289 		skb = skb_clone(skb, GFP_ATOMIC);
2290 		kfree_skb(tmp_skb);
2291 
2292 		if (!skb) {
2293 			ret = -ENOMEM;
2294 			goto free;
2295 		}
2296 	}
2297 
2298 	hdr.frame_control = fc;
2299 	hdr.duration_id = 0;
2300 	hdr.seq_ctrl = 0;
2301 
2302 	skip_header_bytes = ETH_HLEN;
2303 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2304 		encaps_data = bridge_tunnel_header;
2305 		encaps_len = sizeof(bridge_tunnel_header);
2306 		skip_header_bytes -= 2;
2307 	} else if (ethertype >= ETH_P_802_3_MIN) {
2308 		encaps_data = rfc1042_header;
2309 		encaps_len = sizeof(rfc1042_header);
2310 		skip_header_bytes -= 2;
2311 	} else {
2312 		encaps_data = NULL;
2313 		encaps_len = 0;
2314 	}
2315 
2316 	nh_pos = skb_network_header(skb) - skb->data;
2317 	h_pos = skb_transport_header(skb) - skb->data;
2318 
2319 	skb_pull(skb, skip_header_bytes);
2320 	nh_pos -= skip_header_bytes;
2321 	h_pos -= skip_header_bytes;
2322 
2323 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2324 
2325 	/*
2326 	 * So we need to modify the skb header and hence need a copy of
2327 	 * that. The head_need variable above doesn't, so far, include
2328 	 * the needed header space that we don't need right away. If we
2329 	 * can, then we don't reallocate right now but only after the
2330 	 * frame arrives at the master device (if it does...)
2331 	 *
2332 	 * If we cannot, however, then we will reallocate to include all
2333 	 * the ever needed space. Also, if we need to reallocate it anyway,
2334 	 * make it big enough for everything we may ever need.
2335 	 */
2336 
2337 	if (head_need > 0 || skb_cloned(skb)) {
2338 		head_need += sdata->encrypt_headroom;
2339 		head_need += local->tx_headroom;
2340 		head_need = max_t(int, 0, head_need);
2341 		if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
2342 			ieee80211_free_txskb(&local->hw, skb);
2343 			skb = NULL;
2344 			return ERR_PTR(-ENOMEM);
2345 		}
2346 	}
2347 
2348 	if (encaps_data) {
2349 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2350 		nh_pos += encaps_len;
2351 		h_pos += encaps_len;
2352 	}
2353 
2354 #ifdef CONFIG_MAC80211_MESH
2355 	if (meshhdrlen > 0) {
2356 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2357 		nh_pos += meshhdrlen;
2358 		h_pos += meshhdrlen;
2359 	}
2360 #endif
2361 
2362 	if (ieee80211_is_data_qos(fc)) {
2363 		__le16 *qos_control;
2364 
2365 		qos_control = (__le16 *) skb_push(skb, 2);
2366 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2367 		/*
2368 		 * Maybe we could actually set some fields here, for now just
2369 		 * initialise to zero to indicate no special operation.
2370 		 */
2371 		*qos_control = 0;
2372 	} else
2373 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2374 
2375 	nh_pos += hdrlen;
2376 	h_pos += hdrlen;
2377 
2378 	/* Update skb pointers to various headers since this modified frame
2379 	 * is going to go through Linux networking code that may potentially
2380 	 * need things like pointer to IP header. */
2381 	skb_set_mac_header(skb, 0);
2382 	skb_set_network_header(skb, nh_pos);
2383 	skb_set_transport_header(skb, h_pos);
2384 
2385 	info = IEEE80211_SKB_CB(skb);
2386 	memset(info, 0, sizeof(*info));
2387 
2388 	info->flags = info_flags;
2389 	info->ack_frame_id = info_id;
2390 	info->band = band;
2391 
2392 	return skb;
2393  free:
2394 	kfree_skb(skb);
2395 	return ERR_PTR(ret);
2396 }
2397 
2398 /*
2399  * fast-xmit overview
2400  *
2401  * The core idea of this fast-xmit is to remove per-packet checks by checking
2402  * them out of band. ieee80211_check_fast_xmit() implements the out-of-band
2403  * checks that are needed to get the sta->fast_tx pointer assigned, after which
2404  * much less work can be done per packet. For example, fragmentation must be
2405  * disabled or the fast_tx pointer will not be set. All the conditions are seen
2406  * in the code here.
2407  *
2408  * Once assigned, the fast_tx data structure also caches the per-packet 802.11
2409  * header and other data to aid packet processing in ieee80211_xmit_fast().
2410  *
2411  * The most difficult part of this is that when any of these assumptions
2412  * change, an external trigger (i.e. a call to ieee80211_clear_fast_xmit(),
2413  * ieee80211_check_fast_xmit() or friends) is required to reset the data,
2414  * since the per-packet code no longer checks the conditions. This is reflected
2415  * by the calls to these functions throughout the rest of the code, and must be
2416  * maintained if any of the TX path checks change.
2417  */
2418 
2419 void ieee80211_check_fast_xmit(struct sta_info *sta)
2420 {
2421 	struct ieee80211_fast_tx build = {}, *fast_tx = NULL, *old;
2422 	struct ieee80211_local *local = sta->local;
2423 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2424 	struct ieee80211_hdr *hdr = (void *)build.hdr;
2425 	struct ieee80211_chanctx_conf *chanctx_conf;
2426 	__le16 fc;
2427 
2428 	if (!ieee80211_hw_check(&local->hw, SUPPORT_FAST_XMIT))
2429 		return;
2430 
2431 	/* Locking here protects both the pointer itself, and against concurrent
2432 	 * invocations winning data access races to, e.g., the key pointer that
2433 	 * is used.
2434 	 * Without it, the invocation of this function right after the key
2435 	 * pointer changes wouldn't be sufficient, as another CPU could access
2436 	 * the pointer, then stall, and then do the cache update after the CPU
2437 	 * that invalidated the key.
2438 	 * With the locking, such scenarios cannot happen as the check for the
2439 	 * key and the fast-tx assignment are done atomically, so the CPU that
2440 	 * modifies the key will either wait or other one will see the key
2441 	 * cleared/changed already.
2442 	 */
2443 	spin_lock_bh(&sta->lock);
2444 	if (ieee80211_hw_check(&local->hw, SUPPORTS_PS) &&
2445 	    !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS) &&
2446 	    sdata->vif.type == NL80211_IFTYPE_STATION)
2447 		goto out;
2448 
2449 	if (!test_sta_flag(sta, WLAN_STA_AUTHORIZED))
2450 		goto out;
2451 
2452 	if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
2453 	    test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
2454 	    test_sta_flag(sta, WLAN_STA_PS_DELIVER))
2455 		goto out;
2456 
2457 	if (sdata->noack_map)
2458 		goto out;
2459 
2460 	/* fast-xmit doesn't handle fragmentation at all */
2461 	if (local->hw.wiphy->frag_threshold != (u32)-1 &&
2462 	    !local->ops->set_frag_threshold)
2463 		goto out;
2464 
2465 	rcu_read_lock();
2466 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2467 	if (!chanctx_conf) {
2468 		rcu_read_unlock();
2469 		goto out;
2470 	}
2471 	build.band = chanctx_conf->def.chan->band;
2472 	rcu_read_unlock();
2473 
2474 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
2475 
2476 	switch (sdata->vif.type) {
2477 	case NL80211_IFTYPE_ADHOC:
2478 		/* DA SA BSSID */
2479 		build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2480 		build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2481 		memcpy(hdr->addr3, sdata->u.ibss.bssid, ETH_ALEN);
2482 		build.hdr_len = 24;
2483 		break;
2484 	case NL80211_IFTYPE_STATION:
2485 		if (test_sta_flag(sta, WLAN_STA_TDLS_PEER)) {
2486 			/* DA SA BSSID */
2487 			build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2488 			build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2489 			memcpy(hdr->addr3, sdata->u.mgd.bssid, ETH_ALEN);
2490 			build.hdr_len = 24;
2491 			break;
2492 		}
2493 
2494 		if (sdata->u.mgd.use_4addr) {
2495 			/* non-regular ethertype cannot use the fastpath */
2496 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2497 					  IEEE80211_FCTL_TODS);
2498 			/* RA TA DA SA */
2499 			memcpy(hdr->addr1, sdata->u.mgd.bssid, ETH_ALEN);
2500 			memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2501 			build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2502 			build.sa_offs = offsetof(struct ieee80211_hdr, addr4);
2503 			build.hdr_len = 30;
2504 			break;
2505 		}
2506 		fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
2507 		/* BSSID SA DA */
2508 		memcpy(hdr->addr1, sdata->u.mgd.bssid, ETH_ALEN);
2509 		build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2510 		build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
2511 		build.hdr_len = 24;
2512 		break;
2513 	case NL80211_IFTYPE_AP_VLAN:
2514 		if (sdata->wdev.use_4addr) {
2515 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
2516 					  IEEE80211_FCTL_TODS);
2517 			/* RA TA DA SA */
2518 			memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
2519 			memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2520 			build.da_offs = offsetof(struct ieee80211_hdr, addr3);
2521 			build.sa_offs = offsetof(struct ieee80211_hdr, addr4);
2522 			build.hdr_len = 30;
2523 			break;
2524 		}
2525 		/* fall through */
2526 	case NL80211_IFTYPE_AP:
2527 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
2528 		/* DA BSSID SA */
2529 		build.da_offs = offsetof(struct ieee80211_hdr, addr1);
2530 		memcpy(hdr->addr2, sdata->vif.addr, ETH_ALEN);
2531 		build.sa_offs = offsetof(struct ieee80211_hdr, addr3);
2532 		build.hdr_len = 24;
2533 		break;
2534 	default:
2535 		/* not handled on fast-xmit */
2536 		goto out;
2537 	}
2538 
2539 	if (sta->sta.wme) {
2540 		build.hdr_len += 2;
2541 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2542 	}
2543 
2544 	/* We store the key here so there's no point in using rcu_dereference()
2545 	 * but that's fine because the code that changes the pointers will call
2546 	 * this function after doing so. For a single CPU that would be enough,
2547 	 * for multiple see the comment above.
2548 	 */
2549 	build.key = rcu_access_pointer(sta->ptk[sta->ptk_idx]);
2550 	if (!build.key)
2551 		build.key = rcu_access_pointer(sdata->default_unicast_key);
2552 	if (build.key) {
2553 		bool gen_iv, iv_spc, mmic;
2554 
2555 		gen_iv = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
2556 		iv_spc = build.key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
2557 		mmic = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC;
2558 
2559 		/* don't handle software crypto */
2560 		if (!(build.key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
2561 			goto out;
2562 
2563 		switch (build.key->conf.cipher) {
2564 		case WLAN_CIPHER_SUITE_CCMP:
2565 		case WLAN_CIPHER_SUITE_CCMP_256:
2566 			/* add fixed key ID */
2567 			if (gen_iv) {
2568 				(build.hdr + build.hdr_len)[3] =
2569 					0x20 | (build.key->conf.keyidx << 6);
2570 				build.pn_offs = build.hdr_len;
2571 			}
2572 			if (gen_iv || iv_spc)
2573 				build.hdr_len += IEEE80211_CCMP_HDR_LEN;
2574 			break;
2575 		case WLAN_CIPHER_SUITE_GCMP:
2576 		case WLAN_CIPHER_SUITE_GCMP_256:
2577 			/* add fixed key ID */
2578 			if (gen_iv) {
2579 				(build.hdr + build.hdr_len)[3] =
2580 					0x20 | (build.key->conf.keyidx << 6);
2581 				build.pn_offs = build.hdr_len;
2582 			}
2583 			if (gen_iv || iv_spc)
2584 				build.hdr_len += IEEE80211_GCMP_HDR_LEN;
2585 			break;
2586 		case WLAN_CIPHER_SUITE_TKIP:
2587 			/* cannot handle MMIC or IV generation in xmit-fast */
2588 			if (mmic || gen_iv)
2589 				goto out;
2590 			if (iv_spc)
2591 				build.hdr_len += IEEE80211_TKIP_IV_LEN;
2592 			break;
2593 		case WLAN_CIPHER_SUITE_WEP40:
2594 		case WLAN_CIPHER_SUITE_WEP104:
2595 			/* cannot handle IV generation in fast-xmit */
2596 			if (gen_iv)
2597 				goto out;
2598 			if (iv_spc)
2599 				build.hdr_len += IEEE80211_WEP_IV_LEN;
2600 			break;
2601 		case WLAN_CIPHER_SUITE_AES_CMAC:
2602 		case WLAN_CIPHER_SUITE_BIP_CMAC_256:
2603 		case WLAN_CIPHER_SUITE_BIP_GMAC_128:
2604 		case WLAN_CIPHER_SUITE_BIP_GMAC_256:
2605 			WARN(1,
2606 			     "management cipher suite 0x%x enabled for data\n",
2607 			     build.key->conf.cipher);
2608 			goto out;
2609 		default:
2610 			/* we don't know how to generate IVs for this at all */
2611 			if (WARN_ON(gen_iv))
2612 				goto out;
2613 			/* pure hardware keys are OK, of course */
2614 			if (!(build.key->flags & KEY_FLAG_CIPHER_SCHEME))
2615 				break;
2616 			/* cipher scheme might require space allocation */
2617 			if (iv_spc &&
2618 			    build.key->conf.iv_len > IEEE80211_FAST_XMIT_MAX_IV)
2619 				goto out;
2620 			if (iv_spc)
2621 				build.hdr_len += build.key->conf.iv_len;
2622 		}
2623 
2624 		fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
2625 	}
2626 
2627 	hdr->frame_control = fc;
2628 
2629 	memcpy(build.hdr + build.hdr_len,
2630 	       rfc1042_header,  sizeof(rfc1042_header));
2631 	build.hdr_len += sizeof(rfc1042_header);
2632 
2633 	fast_tx = kmemdup(&build, sizeof(build), GFP_ATOMIC);
2634 	/* if the kmemdup fails, continue w/o fast_tx */
2635 	if (!fast_tx)
2636 		goto out;
2637 
2638  out:
2639 	/* we might have raced against another call to this function */
2640 	old = rcu_dereference_protected(sta->fast_tx,
2641 					lockdep_is_held(&sta->lock));
2642 	rcu_assign_pointer(sta->fast_tx, fast_tx);
2643 	if (old)
2644 		kfree_rcu(old, rcu_head);
2645 	spin_unlock_bh(&sta->lock);
2646 }
2647 
2648 void ieee80211_check_fast_xmit_all(struct ieee80211_local *local)
2649 {
2650 	struct sta_info *sta;
2651 
2652 	rcu_read_lock();
2653 	list_for_each_entry_rcu(sta, &local->sta_list, list)
2654 		ieee80211_check_fast_xmit(sta);
2655 	rcu_read_unlock();
2656 }
2657 
2658 void ieee80211_check_fast_xmit_iface(struct ieee80211_sub_if_data *sdata)
2659 {
2660 	struct ieee80211_local *local = sdata->local;
2661 	struct sta_info *sta;
2662 
2663 	rcu_read_lock();
2664 
2665 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
2666 		if (sdata != sta->sdata &&
2667 		    (!sta->sdata->bss || sta->sdata->bss != sdata->bss))
2668 			continue;
2669 		ieee80211_check_fast_xmit(sta);
2670 	}
2671 
2672 	rcu_read_unlock();
2673 }
2674 
2675 void ieee80211_clear_fast_xmit(struct sta_info *sta)
2676 {
2677 	struct ieee80211_fast_tx *fast_tx;
2678 
2679 	spin_lock_bh(&sta->lock);
2680 	fast_tx = rcu_dereference_protected(sta->fast_tx,
2681 					    lockdep_is_held(&sta->lock));
2682 	RCU_INIT_POINTER(sta->fast_tx, NULL);
2683 	spin_unlock_bh(&sta->lock);
2684 
2685 	if (fast_tx)
2686 		kfree_rcu(fast_tx, rcu_head);
2687 }
2688 
2689 static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata,
2690 				struct net_device *dev, struct sta_info *sta,
2691 				struct ieee80211_fast_tx *fast_tx,
2692 				struct sk_buff *skb)
2693 {
2694 	struct ieee80211_local *local = sdata->local;
2695 	u16 ethertype = (skb->data[12] << 8) | skb->data[13];
2696 	int extra_head = fast_tx->hdr_len - (ETH_HLEN - 2);
2697 	int hw_headroom = sdata->local->hw.extra_tx_headroom;
2698 	struct ethhdr eth;
2699 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2700 	struct ieee80211_hdr *hdr = (void *)fast_tx->hdr;
2701 	struct ieee80211_tx_data tx;
2702 	ieee80211_tx_result r;
2703 	struct tid_ampdu_tx *tid_tx = NULL;
2704 	u8 tid = IEEE80211_NUM_TIDS;
2705 
2706 	/* control port protocol needs a lot of special handling */
2707 	if (cpu_to_be16(ethertype) == sdata->control_port_protocol)
2708 		return false;
2709 
2710 	/* only RFC 1042 SNAP */
2711 	if (ethertype < ETH_P_802_3_MIN)
2712 		return false;
2713 
2714 	/* don't handle TX status request here either */
2715 	if (skb->sk && skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)
2716 		return false;
2717 
2718 	if (hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) {
2719 		tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
2720 		tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
2721 		if (tid_tx) {
2722 			if (!test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state))
2723 				return false;
2724 			if (tid_tx->timeout)
2725 				tid_tx->last_tx = jiffies;
2726 		}
2727 	}
2728 
2729 	/* after this point (skb is modified) we cannot return false */
2730 
2731 	if (skb_shared(skb)) {
2732 		struct sk_buff *tmp_skb = skb;
2733 
2734 		skb = skb_clone(skb, GFP_ATOMIC);
2735 		kfree_skb(tmp_skb);
2736 
2737 		if (!skb)
2738 			return true;
2739 	}
2740 
2741 	ieee80211_tx_stats(dev, skb->len + extra_head);
2742 
2743 	/* will not be crypto-handled beyond what we do here, so use false
2744 	 * as the may-encrypt argument for the resize to not account for
2745 	 * more room than we already have in 'extra_head'
2746 	 */
2747 	if (unlikely(ieee80211_skb_resize(sdata, skb,
2748 					  max_t(int, extra_head + hw_headroom -
2749 						     skb_headroom(skb), 0),
2750 					  false))) {
2751 		kfree_skb(skb);
2752 		return true;
2753 	}
2754 
2755 	memcpy(&eth, skb->data, ETH_HLEN - 2);
2756 	hdr = (void *)skb_push(skb, extra_head);
2757 	memcpy(skb->data, fast_tx->hdr, fast_tx->hdr_len);
2758 	memcpy(skb->data + fast_tx->da_offs, eth.h_dest, ETH_ALEN);
2759 	memcpy(skb->data + fast_tx->sa_offs, eth.h_source, ETH_ALEN);
2760 
2761 	memset(info, 0, sizeof(*info));
2762 	info->band = fast_tx->band;
2763 	info->control.vif = &sdata->vif;
2764 	info->flags = IEEE80211_TX_CTL_FIRST_FRAGMENT |
2765 		      IEEE80211_TX_CTL_DONTFRAG |
2766 		      (tid_tx ? IEEE80211_TX_CTL_AMPDU : 0);
2767 
2768 	if (hdr->frame_control & cpu_to_le16(IEEE80211_STYPE_QOS_DATA)) {
2769 		*ieee80211_get_qos_ctl(hdr) = tid;
2770 		hdr->seq_ctrl = ieee80211_tx_next_seq(sta, tid);
2771 	} else {
2772 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
2773 		hdr->seq_ctrl = cpu_to_le16(sdata->sequence_number);
2774 		sdata->sequence_number += 0x10;
2775 	}
2776 
2777 	if (skb_shinfo(skb)->gso_size)
2778 		sta->tx_msdu[tid] +=
2779 			DIV_ROUND_UP(skb->len, skb_shinfo(skb)->gso_size);
2780 	else
2781 		sta->tx_msdu[tid]++;
2782 
2783 	info->hw_queue = sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
2784 
2785 	__skb_queue_head_init(&tx.skbs);
2786 
2787 	tx.flags = IEEE80211_TX_UNICAST;
2788 	tx.local = local;
2789 	tx.sdata = sdata;
2790 	tx.sta = sta;
2791 	tx.key = fast_tx->key;
2792 
2793 	if (fast_tx->key)
2794 		info->control.hw_key = &fast_tx->key->conf;
2795 
2796 	if (!ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
2797 		tx.skb = skb;
2798 		r = ieee80211_tx_h_rate_ctrl(&tx);
2799 		skb = tx.skb;
2800 		tx.skb = NULL;
2801 
2802 		if (r != TX_CONTINUE) {
2803 			if (r != TX_QUEUED)
2804 				kfree_skb(skb);
2805 			return true;
2806 		}
2807 	}
2808 
2809 	/* statistics normally done by ieee80211_tx_h_stats (but that
2810 	 * has to consider fragmentation, so is more complex)
2811 	 */
2812 	sta->tx_bytes[skb_get_queue_mapping(skb)] += skb->len;
2813 	sta->tx_packets[skb_get_queue_mapping(skb)]++;
2814 
2815 	if (fast_tx->pn_offs) {
2816 		u64 pn;
2817 		u8 *crypto_hdr = skb->data + fast_tx->pn_offs;
2818 
2819 		switch (fast_tx->key->conf.cipher) {
2820 		case WLAN_CIPHER_SUITE_CCMP:
2821 		case WLAN_CIPHER_SUITE_CCMP_256:
2822 		case WLAN_CIPHER_SUITE_GCMP:
2823 		case WLAN_CIPHER_SUITE_GCMP_256:
2824 			pn = atomic64_inc_return(&fast_tx->key->conf.tx_pn);
2825 			crypto_hdr[0] = pn;
2826 			crypto_hdr[1] = pn >> 8;
2827 			crypto_hdr[4] = pn >> 16;
2828 			crypto_hdr[5] = pn >> 24;
2829 			crypto_hdr[6] = pn >> 32;
2830 			crypto_hdr[7] = pn >> 40;
2831 			break;
2832 		}
2833 	}
2834 
2835 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2836 		sdata = container_of(sdata->bss,
2837 				     struct ieee80211_sub_if_data, u.ap);
2838 
2839 	__skb_queue_tail(&tx.skbs, skb);
2840 	ieee80211_tx_frags(local, &sdata->vif, &sta->sta, &tx.skbs, false);
2841 	return true;
2842 }
2843 
2844 void __ieee80211_subif_start_xmit(struct sk_buff *skb,
2845 				  struct net_device *dev,
2846 				  u32 info_flags)
2847 {
2848 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
2849 	struct sta_info *sta;
2850 	struct sk_buff *next;
2851 
2852 	if (unlikely(skb->len < ETH_HLEN)) {
2853 		kfree_skb(skb);
2854 		return;
2855 	}
2856 
2857 	rcu_read_lock();
2858 
2859 	if (ieee80211_lookup_ra_sta(sdata, skb, &sta))
2860 		goto out_free;
2861 
2862 	if (!IS_ERR_OR_NULL(sta)) {
2863 		struct ieee80211_fast_tx *fast_tx;
2864 
2865 		fast_tx = rcu_dereference(sta->fast_tx);
2866 
2867 		if (fast_tx &&
2868 		    ieee80211_xmit_fast(sdata, dev, sta, fast_tx, skb))
2869 			goto out;
2870 	}
2871 
2872 	if (skb_is_gso(skb)) {
2873 		struct sk_buff *segs;
2874 
2875 		segs = skb_gso_segment(skb, 0);
2876 		if (IS_ERR(segs)) {
2877 			goto out_free;
2878 		} else if (segs) {
2879 			consume_skb(skb);
2880 			skb = segs;
2881 		}
2882 	} else {
2883 		/* we cannot process non-linear frames on this path */
2884 		if (skb_linearize(skb)) {
2885 			kfree_skb(skb);
2886 			goto out;
2887 		}
2888 
2889 		/* the frame could be fragmented, software-encrypted, and other
2890 		 * things so we cannot really handle checksum offload with it -
2891 		 * fix it up in software before we handle anything else.
2892 		 */
2893 		if (skb->ip_summed == CHECKSUM_PARTIAL) {
2894 			skb_set_transport_header(skb,
2895 						 skb_checksum_start_offset(skb));
2896 			if (skb_checksum_help(skb))
2897 				goto out_free;
2898 		}
2899 	}
2900 
2901 	next = skb;
2902 	while (next) {
2903 		skb = next;
2904 		next = skb->next;
2905 
2906 		skb->prev = NULL;
2907 		skb->next = NULL;
2908 
2909 		skb = ieee80211_build_hdr(sdata, skb, info_flags, sta);
2910 		if (IS_ERR(skb))
2911 			goto out;
2912 
2913 		ieee80211_tx_stats(dev, skb->len);
2914 
2915 		ieee80211_xmit(sdata, sta, skb);
2916 	}
2917 	goto out;
2918  out_free:
2919 	kfree_skb(skb);
2920  out:
2921 	rcu_read_unlock();
2922 }
2923 
2924 /**
2925  * ieee80211_subif_start_xmit - netif start_xmit function for 802.3 vifs
2926  * @skb: packet to be sent
2927  * @dev: incoming interface
2928  *
2929  * On failure skb will be freed.
2930  */
2931 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
2932 				       struct net_device *dev)
2933 {
2934 	__ieee80211_subif_start_xmit(skb, dev, 0);
2935 	return NETDEV_TX_OK;
2936 }
2937 
2938 struct sk_buff *
2939 ieee80211_build_data_template(struct ieee80211_sub_if_data *sdata,
2940 			      struct sk_buff *skb, u32 info_flags)
2941 {
2942 	struct ieee80211_hdr *hdr;
2943 	struct ieee80211_tx_data tx = {
2944 		.local = sdata->local,
2945 		.sdata = sdata,
2946 	};
2947 	struct sta_info *sta;
2948 
2949 	rcu_read_lock();
2950 
2951 	if (ieee80211_lookup_ra_sta(sdata, skb, &sta)) {
2952 		kfree_skb(skb);
2953 		skb = ERR_PTR(-EINVAL);
2954 		goto out;
2955 	}
2956 
2957 	skb = ieee80211_build_hdr(sdata, skb, info_flags, sta);
2958 	if (IS_ERR(skb))
2959 		goto out;
2960 
2961 	hdr = (void *)skb->data;
2962 	tx.sta = sta_info_get(sdata, hdr->addr1);
2963 	tx.skb = skb;
2964 
2965 	if (ieee80211_tx_h_select_key(&tx) != TX_CONTINUE) {
2966 		rcu_read_unlock();
2967 		kfree_skb(skb);
2968 		return ERR_PTR(-EINVAL);
2969 	}
2970 
2971 out:
2972 	rcu_read_unlock();
2973 	return skb;
2974 }
2975 
2976 /*
2977  * ieee80211_clear_tx_pending may not be called in a context where
2978  * it is possible that it packets could come in again.
2979  */
2980 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2981 {
2982 	struct sk_buff *skb;
2983 	int i;
2984 
2985 	for (i = 0; i < local->hw.queues; i++) {
2986 		while ((skb = skb_dequeue(&local->pending[i])) != NULL)
2987 			ieee80211_free_txskb(&local->hw, skb);
2988 	}
2989 }
2990 
2991 /*
2992  * Returns false if the frame couldn't be transmitted but was queued instead,
2993  * which in this case means re-queued -- take as an indication to stop sending
2994  * more pending frames.
2995  */
2996 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2997 				     struct sk_buff *skb)
2998 {
2999 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3000 	struct ieee80211_sub_if_data *sdata;
3001 	struct sta_info *sta;
3002 	struct ieee80211_hdr *hdr;
3003 	bool result;
3004 	struct ieee80211_chanctx_conf *chanctx_conf;
3005 
3006 	sdata = vif_to_sdata(info->control.vif);
3007 
3008 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
3009 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
3010 		if (unlikely(!chanctx_conf)) {
3011 			dev_kfree_skb(skb);
3012 			return true;
3013 		}
3014 		info->band = chanctx_conf->def.chan->band;
3015 		result = ieee80211_tx(sdata, NULL, skb, true);
3016 	} else {
3017 		struct sk_buff_head skbs;
3018 
3019 		__skb_queue_head_init(&skbs);
3020 		__skb_queue_tail(&skbs, skb);
3021 
3022 		hdr = (struct ieee80211_hdr *)skb->data;
3023 		sta = sta_info_get(sdata, hdr->addr1);
3024 
3025 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
3026 	}
3027 
3028 	return result;
3029 }
3030 
3031 /*
3032  * Transmit all pending packets. Called from tasklet.
3033  */
3034 void ieee80211_tx_pending(unsigned long data)
3035 {
3036 	struct ieee80211_local *local = (struct ieee80211_local *)data;
3037 	unsigned long flags;
3038 	int i;
3039 	bool txok;
3040 
3041 	rcu_read_lock();
3042 
3043 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
3044 	for (i = 0; i < local->hw.queues; i++) {
3045 		/*
3046 		 * If queue is stopped by something other than due to pending
3047 		 * frames, or we have no pending frames, proceed to next queue.
3048 		 */
3049 		if (local->queue_stop_reasons[i] ||
3050 		    skb_queue_empty(&local->pending[i]))
3051 			continue;
3052 
3053 		while (!skb_queue_empty(&local->pending[i])) {
3054 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
3055 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
3056 
3057 			if (WARN_ON(!info->control.vif)) {
3058 				ieee80211_free_txskb(&local->hw, skb);
3059 				continue;
3060 			}
3061 
3062 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
3063 						flags);
3064 
3065 			txok = ieee80211_tx_pending_skb(local, skb);
3066 			spin_lock_irqsave(&local->queue_stop_reason_lock,
3067 					  flags);
3068 			if (!txok)
3069 				break;
3070 		}
3071 
3072 		if (skb_queue_empty(&local->pending[i]))
3073 			ieee80211_propagate_queue_wake(local, i);
3074 	}
3075 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
3076 
3077 	rcu_read_unlock();
3078 }
3079 
3080 /* functions for drivers to get certain frames */
3081 
3082 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
3083 				       struct ps_data *ps, struct sk_buff *skb,
3084 				       bool is_template)
3085 {
3086 	u8 *pos, *tim;
3087 	int aid0 = 0;
3088 	int i, have_bits = 0, n1, n2;
3089 
3090 	/* Generate bitmap for TIM only if there are any STAs in power save
3091 	 * mode. */
3092 	if (atomic_read(&ps->num_sta_ps) > 0)
3093 		/* in the hope that this is faster than
3094 		 * checking byte-for-byte */
3095 		have_bits = !bitmap_empty((unsigned long *)ps->tim,
3096 					  IEEE80211_MAX_AID+1);
3097 	if (!is_template) {
3098 		if (ps->dtim_count == 0)
3099 			ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
3100 		else
3101 			ps->dtim_count--;
3102 	}
3103 
3104 	tim = pos = (u8 *) skb_put(skb, 6);
3105 	*pos++ = WLAN_EID_TIM;
3106 	*pos++ = 4;
3107 	*pos++ = ps->dtim_count;
3108 	*pos++ = sdata->vif.bss_conf.dtim_period;
3109 
3110 	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
3111 		aid0 = 1;
3112 
3113 	ps->dtim_bc_mc = aid0 == 1;
3114 
3115 	if (have_bits) {
3116 		/* Find largest even number N1 so that bits numbered 1 through
3117 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
3118 		 * (N2 + 1) x 8 through 2007 are 0. */
3119 		n1 = 0;
3120 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
3121 			if (ps->tim[i]) {
3122 				n1 = i & 0xfe;
3123 				break;
3124 			}
3125 		}
3126 		n2 = n1;
3127 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
3128 			if (ps->tim[i]) {
3129 				n2 = i;
3130 				break;
3131 			}
3132 		}
3133 
3134 		/* Bitmap control */
3135 		*pos++ = n1 | aid0;
3136 		/* Part Virt Bitmap */
3137 		skb_put(skb, n2 - n1);
3138 		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
3139 
3140 		tim[1] = n2 - n1 + 4;
3141 	} else {
3142 		*pos++ = aid0; /* Bitmap control */
3143 		*pos++ = 0; /* Part Virt Bitmap */
3144 	}
3145 }
3146 
3147 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
3148 				    struct ps_data *ps, struct sk_buff *skb,
3149 				    bool is_template)
3150 {
3151 	struct ieee80211_local *local = sdata->local;
3152 
3153 	/*
3154 	 * Not very nice, but we want to allow the driver to call
3155 	 * ieee80211_beacon_get() as a response to the set_tim()
3156 	 * callback. That, however, is already invoked under the
3157 	 * sta_lock to guarantee consistent and race-free update
3158 	 * of the tim bitmap in mac80211 and the driver.
3159 	 */
3160 	if (local->tim_in_locked_section) {
3161 		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
3162 	} else {
3163 		spin_lock_bh(&local->tim_lock);
3164 		__ieee80211_beacon_add_tim(sdata, ps, skb, is_template);
3165 		spin_unlock_bh(&local->tim_lock);
3166 	}
3167 
3168 	return 0;
3169 }
3170 
3171 static void ieee80211_set_csa(struct ieee80211_sub_if_data *sdata,
3172 			      struct beacon_data *beacon)
3173 {
3174 	struct probe_resp *resp;
3175 	u8 *beacon_data;
3176 	size_t beacon_data_len;
3177 	int i;
3178 	u8 count = beacon->csa_current_counter;
3179 
3180 	switch (sdata->vif.type) {
3181 	case NL80211_IFTYPE_AP:
3182 		beacon_data = beacon->tail;
3183 		beacon_data_len = beacon->tail_len;
3184 		break;
3185 	case NL80211_IFTYPE_ADHOC:
3186 		beacon_data = beacon->head;
3187 		beacon_data_len = beacon->head_len;
3188 		break;
3189 	case NL80211_IFTYPE_MESH_POINT:
3190 		beacon_data = beacon->head;
3191 		beacon_data_len = beacon->head_len;
3192 		break;
3193 	default:
3194 		return;
3195 	}
3196 
3197 	rcu_read_lock();
3198 	for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; ++i) {
3199 		resp = rcu_dereference(sdata->u.ap.probe_resp);
3200 
3201 		if (beacon->csa_counter_offsets[i]) {
3202 			if (WARN_ON_ONCE(beacon->csa_counter_offsets[i] >=
3203 					 beacon_data_len)) {
3204 				rcu_read_unlock();
3205 				return;
3206 			}
3207 
3208 			beacon_data[beacon->csa_counter_offsets[i]] = count;
3209 		}
3210 
3211 		if (sdata->vif.type == NL80211_IFTYPE_AP && resp)
3212 			resp->data[resp->csa_counter_offsets[i]] = count;
3213 	}
3214 	rcu_read_unlock();
3215 }
3216 
3217 static u8 __ieee80211_csa_update_counter(struct beacon_data *beacon)
3218 {
3219 	beacon->csa_current_counter--;
3220 
3221 	/* the counter should never reach 0 */
3222 	WARN_ON_ONCE(!beacon->csa_current_counter);
3223 
3224 	return beacon->csa_current_counter;
3225 }
3226 
3227 u8 ieee80211_csa_update_counter(struct ieee80211_vif *vif)
3228 {
3229 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3230 	struct beacon_data *beacon = NULL;
3231 	u8 count = 0;
3232 
3233 	rcu_read_lock();
3234 
3235 	if (sdata->vif.type == NL80211_IFTYPE_AP)
3236 		beacon = rcu_dereference(sdata->u.ap.beacon);
3237 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
3238 		beacon = rcu_dereference(sdata->u.ibss.presp);
3239 	else if (ieee80211_vif_is_mesh(&sdata->vif))
3240 		beacon = rcu_dereference(sdata->u.mesh.beacon);
3241 
3242 	if (!beacon)
3243 		goto unlock;
3244 
3245 	count = __ieee80211_csa_update_counter(beacon);
3246 
3247 unlock:
3248 	rcu_read_unlock();
3249 	return count;
3250 }
3251 EXPORT_SYMBOL(ieee80211_csa_update_counter);
3252 
3253 bool ieee80211_csa_is_complete(struct ieee80211_vif *vif)
3254 {
3255 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3256 	struct beacon_data *beacon = NULL;
3257 	u8 *beacon_data;
3258 	size_t beacon_data_len;
3259 	int ret = false;
3260 
3261 	if (!ieee80211_sdata_running(sdata))
3262 		return false;
3263 
3264 	rcu_read_lock();
3265 	if (vif->type == NL80211_IFTYPE_AP) {
3266 		struct ieee80211_if_ap *ap = &sdata->u.ap;
3267 
3268 		beacon = rcu_dereference(ap->beacon);
3269 		if (WARN_ON(!beacon || !beacon->tail))
3270 			goto out;
3271 		beacon_data = beacon->tail;
3272 		beacon_data_len = beacon->tail_len;
3273 	} else if (vif->type == NL80211_IFTYPE_ADHOC) {
3274 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
3275 
3276 		beacon = rcu_dereference(ifibss->presp);
3277 		if (!beacon)
3278 			goto out;
3279 
3280 		beacon_data = beacon->head;
3281 		beacon_data_len = beacon->head_len;
3282 	} else if (vif->type == NL80211_IFTYPE_MESH_POINT) {
3283 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
3284 
3285 		beacon = rcu_dereference(ifmsh->beacon);
3286 		if (!beacon)
3287 			goto out;
3288 
3289 		beacon_data = beacon->head;
3290 		beacon_data_len = beacon->head_len;
3291 	} else {
3292 		WARN_ON(1);
3293 		goto out;
3294 	}
3295 
3296 	if (!beacon->csa_counter_offsets[0])
3297 		goto out;
3298 
3299 	if (WARN_ON_ONCE(beacon->csa_counter_offsets[0] > beacon_data_len))
3300 		goto out;
3301 
3302 	if (beacon_data[beacon->csa_counter_offsets[0]] == 1)
3303 		ret = true;
3304  out:
3305 	rcu_read_unlock();
3306 
3307 	return ret;
3308 }
3309 EXPORT_SYMBOL(ieee80211_csa_is_complete);
3310 
3311 static struct sk_buff *
3312 __ieee80211_beacon_get(struct ieee80211_hw *hw,
3313 		       struct ieee80211_vif *vif,
3314 		       struct ieee80211_mutable_offsets *offs,
3315 		       bool is_template)
3316 {
3317 	struct ieee80211_local *local = hw_to_local(hw);
3318 	struct beacon_data *beacon = NULL;
3319 	struct sk_buff *skb = NULL;
3320 	struct ieee80211_tx_info *info;
3321 	struct ieee80211_sub_if_data *sdata = NULL;
3322 	enum ieee80211_band band;
3323 	struct ieee80211_tx_rate_control txrc;
3324 	struct ieee80211_chanctx_conf *chanctx_conf;
3325 	int csa_off_base = 0;
3326 
3327 	rcu_read_lock();
3328 
3329 	sdata = vif_to_sdata(vif);
3330 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
3331 
3332 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
3333 		goto out;
3334 
3335 	if (offs)
3336 		memset(offs, 0, sizeof(*offs));
3337 
3338 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
3339 		struct ieee80211_if_ap *ap = &sdata->u.ap;
3340 
3341 		beacon = rcu_dereference(ap->beacon);
3342 		if (beacon) {
3343 			if (beacon->csa_counter_offsets[0]) {
3344 				if (!is_template)
3345 					__ieee80211_csa_update_counter(beacon);
3346 
3347 				ieee80211_set_csa(sdata, beacon);
3348 			}
3349 
3350 			/*
3351 			 * headroom, head length,
3352 			 * tail length and maximum TIM length
3353 			 */
3354 			skb = dev_alloc_skb(local->tx_headroom +
3355 					    beacon->head_len +
3356 					    beacon->tail_len + 256 +
3357 					    local->hw.extra_beacon_tailroom);
3358 			if (!skb)
3359 				goto out;
3360 
3361 			skb_reserve(skb, local->tx_headroom);
3362 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
3363 			       beacon->head_len);
3364 
3365 			ieee80211_beacon_add_tim(sdata, &ap->ps, skb,
3366 						 is_template);
3367 
3368 			if (offs) {
3369 				offs->tim_offset = beacon->head_len;
3370 				offs->tim_length = skb->len - beacon->head_len;
3371 
3372 				/* for AP the csa offsets are from tail */
3373 				csa_off_base = skb->len;
3374 			}
3375 
3376 			if (beacon->tail)
3377 				memcpy(skb_put(skb, beacon->tail_len),
3378 				       beacon->tail, beacon->tail_len);
3379 		} else
3380 			goto out;
3381 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
3382 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
3383 		struct ieee80211_hdr *hdr;
3384 
3385 		beacon = rcu_dereference(ifibss->presp);
3386 		if (!beacon)
3387 			goto out;
3388 
3389 		if (beacon->csa_counter_offsets[0]) {
3390 			if (!is_template)
3391 				__ieee80211_csa_update_counter(beacon);
3392 
3393 			ieee80211_set_csa(sdata, beacon);
3394 		}
3395 
3396 		skb = dev_alloc_skb(local->tx_headroom + beacon->head_len +
3397 				    local->hw.extra_beacon_tailroom);
3398 		if (!skb)
3399 			goto out;
3400 		skb_reserve(skb, local->tx_headroom);
3401 		memcpy(skb_put(skb, beacon->head_len), beacon->head,
3402 		       beacon->head_len);
3403 
3404 		hdr = (struct ieee80211_hdr *) skb->data;
3405 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
3406 						 IEEE80211_STYPE_BEACON);
3407 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
3408 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
3409 
3410 		beacon = rcu_dereference(ifmsh->beacon);
3411 		if (!beacon)
3412 			goto out;
3413 
3414 		if (beacon->csa_counter_offsets[0]) {
3415 			if (!is_template)
3416 				/* TODO: For mesh csa_counter is in TU, so
3417 				 * decrementing it by one isn't correct, but
3418 				 * for now we leave it consistent with overall
3419 				 * mac80211's behavior.
3420 				 */
3421 				__ieee80211_csa_update_counter(beacon);
3422 
3423 			ieee80211_set_csa(sdata, beacon);
3424 		}
3425 
3426 		if (ifmsh->sync_ops)
3427 			ifmsh->sync_ops->adjust_tbtt(sdata, beacon);
3428 
3429 		skb = dev_alloc_skb(local->tx_headroom +
3430 				    beacon->head_len +
3431 				    256 + /* TIM IE */
3432 				    beacon->tail_len +
3433 				    local->hw.extra_beacon_tailroom);
3434 		if (!skb)
3435 			goto out;
3436 		skb_reserve(skb, local->tx_headroom);
3437 		memcpy(skb_put(skb, beacon->head_len), beacon->head,
3438 		       beacon->head_len);
3439 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb, is_template);
3440 
3441 		if (offs) {
3442 			offs->tim_offset = beacon->head_len;
3443 			offs->tim_length = skb->len - beacon->head_len;
3444 		}
3445 
3446 		memcpy(skb_put(skb, beacon->tail_len), beacon->tail,
3447 		       beacon->tail_len);
3448 	} else {
3449 		WARN_ON(1);
3450 		goto out;
3451 	}
3452 
3453 	/* CSA offsets */
3454 	if (offs && beacon) {
3455 		int i;
3456 
3457 		for (i = 0; i < IEEE80211_MAX_CSA_COUNTERS_NUM; i++) {
3458 			u16 csa_off = beacon->csa_counter_offsets[i];
3459 
3460 			if (!csa_off)
3461 				continue;
3462 
3463 			offs->csa_counter_offs[i] = csa_off_base + csa_off;
3464 		}
3465 	}
3466 
3467 	band = chanctx_conf->def.chan->band;
3468 
3469 	info = IEEE80211_SKB_CB(skb);
3470 
3471 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
3472 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
3473 	info->band = band;
3474 
3475 	memset(&txrc, 0, sizeof(txrc));
3476 	txrc.hw = hw;
3477 	txrc.sband = local->hw.wiphy->bands[band];
3478 	txrc.bss_conf = &sdata->vif.bss_conf;
3479 	txrc.skb = skb;
3480 	txrc.reported_rate.idx = -1;
3481 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
3482 	if (txrc.rate_idx_mask == (1 << txrc.sband->n_bitrates) - 1)
3483 		txrc.max_rate_idx = -1;
3484 	else
3485 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
3486 	txrc.bss = true;
3487 	rate_control_get_rate(sdata, NULL, &txrc);
3488 
3489 	info->control.vif = vif;
3490 
3491 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
3492 			IEEE80211_TX_CTL_ASSIGN_SEQ |
3493 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
3494  out:
3495 	rcu_read_unlock();
3496 	return skb;
3497 
3498 }
3499 
3500 struct sk_buff *
3501 ieee80211_beacon_get_template(struct ieee80211_hw *hw,
3502 			      struct ieee80211_vif *vif,
3503 			      struct ieee80211_mutable_offsets *offs)
3504 {
3505 	return __ieee80211_beacon_get(hw, vif, offs, true);
3506 }
3507 EXPORT_SYMBOL(ieee80211_beacon_get_template);
3508 
3509 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
3510 					 struct ieee80211_vif *vif,
3511 					 u16 *tim_offset, u16 *tim_length)
3512 {
3513 	struct ieee80211_mutable_offsets offs = {};
3514 	struct sk_buff *bcn = __ieee80211_beacon_get(hw, vif, &offs, false);
3515 
3516 	if (tim_offset)
3517 		*tim_offset = offs.tim_offset;
3518 
3519 	if (tim_length)
3520 		*tim_length = offs.tim_length;
3521 
3522 	return bcn;
3523 }
3524 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
3525 
3526 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
3527 					struct ieee80211_vif *vif)
3528 {
3529 	struct ieee80211_if_ap *ap = NULL;
3530 	struct sk_buff *skb = NULL;
3531 	struct probe_resp *presp = NULL;
3532 	struct ieee80211_hdr *hdr;
3533 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
3534 
3535 	if (sdata->vif.type != NL80211_IFTYPE_AP)
3536 		return NULL;
3537 
3538 	rcu_read_lock();
3539 
3540 	ap = &sdata->u.ap;
3541 	presp = rcu_dereference(ap->probe_resp);
3542 	if (!presp)
3543 		goto out;
3544 
3545 	skb = dev_alloc_skb(presp->len);
3546 	if (!skb)
3547 		goto out;
3548 
3549 	memcpy(skb_put(skb, presp->len), presp->data, presp->len);
3550 
3551 	hdr = (struct ieee80211_hdr *) skb->data;
3552 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
3553 
3554 out:
3555 	rcu_read_unlock();
3556 	return skb;
3557 }
3558 EXPORT_SYMBOL(ieee80211_proberesp_get);
3559 
3560 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
3561 				     struct ieee80211_vif *vif)
3562 {
3563 	struct ieee80211_sub_if_data *sdata;
3564 	struct ieee80211_if_managed *ifmgd;
3565 	struct ieee80211_pspoll *pspoll;
3566 	struct ieee80211_local *local;
3567 	struct sk_buff *skb;
3568 
3569 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
3570 		return NULL;
3571 
3572 	sdata = vif_to_sdata(vif);
3573 	ifmgd = &sdata->u.mgd;
3574 	local = sdata->local;
3575 
3576 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
3577 	if (!skb)
3578 		return NULL;
3579 
3580 	skb_reserve(skb, local->hw.extra_tx_headroom);
3581 
3582 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
3583 	memset(pspoll, 0, sizeof(*pspoll));
3584 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
3585 					    IEEE80211_STYPE_PSPOLL);
3586 	pspoll->aid = cpu_to_le16(ifmgd->aid);
3587 
3588 	/* aid in PS-Poll has its two MSBs each set to 1 */
3589 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
3590 
3591 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
3592 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
3593 
3594 	return skb;
3595 }
3596 EXPORT_SYMBOL(ieee80211_pspoll_get);
3597 
3598 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
3599 				       struct ieee80211_vif *vif)
3600 {
3601 	struct ieee80211_hdr_3addr *nullfunc;
3602 	struct ieee80211_sub_if_data *sdata;
3603 	struct ieee80211_if_managed *ifmgd;
3604 	struct ieee80211_local *local;
3605 	struct sk_buff *skb;
3606 
3607 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
3608 		return NULL;
3609 
3610 	sdata = vif_to_sdata(vif);
3611 	ifmgd = &sdata->u.mgd;
3612 	local = sdata->local;
3613 
3614 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
3615 	if (!skb)
3616 		return NULL;
3617 
3618 	skb_reserve(skb, local->hw.extra_tx_headroom);
3619 
3620 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
3621 							  sizeof(*nullfunc));
3622 	memset(nullfunc, 0, sizeof(*nullfunc));
3623 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
3624 					      IEEE80211_STYPE_NULLFUNC |
3625 					      IEEE80211_FCTL_TODS);
3626 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
3627 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
3628 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
3629 
3630 	return skb;
3631 }
3632 EXPORT_SYMBOL(ieee80211_nullfunc_get);
3633 
3634 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
3635 				       const u8 *src_addr,
3636 				       const u8 *ssid, size_t ssid_len,
3637 				       size_t tailroom)
3638 {
3639 	struct ieee80211_local *local = hw_to_local(hw);
3640 	struct ieee80211_hdr_3addr *hdr;
3641 	struct sk_buff *skb;
3642 	size_t ie_ssid_len;
3643 	u8 *pos;
3644 
3645 	ie_ssid_len = 2 + ssid_len;
3646 
3647 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
3648 			    ie_ssid_len + tailroom);
3649 	if (!skb)
3650 		return NULL;
3651 
3652 	skb_reserve(skb, local->hw.extra_tx_headroom);
3653 
3654 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
3655 	memset(hdr, 0, sizeof(*hdr));
3656 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
3657 					 IEEE80211_STYPE_PROBE_REQ);
3658 	eth_broadcast_addr(hdr->addr1);
3659 	memcpy(hdr->addr2, src_addr, ETH_ALEN);
3660 	eth_broadcast_addr(hdr->addr3);
3661 
3662 	pos = skb_put(skb, ie_ssid_len);
3663 	*pos++ = WLAN_EID_SSID;
3664 	*pos++ = ssid_len;
3665 	if (ssid_len)
3666 		memcpy(pos, ssid, ssid_len);
3667 	pos += ssid_len;
3668 
3669 	return skb;
3670 }
3671 EXPORT_SYMBOL(ieee80211_probereq_get);
3672 
3673 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
3674 		       const void *frame, size_t frame_len,
3675 		       const struct ieee80211_tx_info *frame_txctl,
3676 		       struct ieee80211_rts *rts)
3677 {
3678 	const struct ieee80211_hdr *hdr = frame;
3679 
3680 	rts->frame_control =
3681 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
3682 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
3683 					       frame_txctl);
3684 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
3685 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
3686 }
3687 EXPORT_SYMBOL(ieee80211_rts_get);
3688 
3689 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
3690 			     const void *frame, size_t frame_len,
3691 			     const struct ieee80211_tx_info *frame_txctl,
3692 			     struct ieee80211_cts *cts)
3693 {
3694 	const struct ieee80211_hdr *hdr = frame;
3695 
3696 	cts->frame_control =
3697 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
3698 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
3699 						     frame_len, frame_txctl);
3700 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
3701 }
3702 EXPORT_SYMBOL(ieee80211_ctstoself_get);
3703 
3704 struct sk_buff *
3705 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
3706 			  struct ieee80211_vif *vif)
3707 {
3708 	struct ieee80211_local *local = hw_to_local(hw);
3709 	struct sk_buff *skb = NULL;
3710 	struct ieee80211_tx_data tx;
3711 	struct ieee80211_sub_if_data *sdata;
3712 	struct ps_data *ps;
3713 	struct ieee80211_tx_info *info;
3714 	struct ieee80211_chanctx_conf *chanctx_conf;
3715 
3716 	sdata = vif_to_sdata(vif);
3717 
3718 	rcu_read_lock();
3719 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
3720 
3721 	if (!chanctx_conf)
3722 		goto out;
3723 
3724 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
3725 		struct beacon_data *beacon =
3726 				rcu_dereference(sdata->u.ap.beacon);
3727 
3728 		if (!beacon || !beacon->head)
3729 			goto out;
3730 
3731 		ps = &sdata->u.ap.ps;
3732 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
3733 		ps = &sdata->u.mesh.ps;
3734 	} else {
3735 		goto out;
3736 	}
3737 
3738 	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
3739 		goto out; /* send buffered bc/mc only after DTIM beacon */
3740 
3741 	while (1) {
3742 		skb = skb_dequeue(&ps->bc_buf);
3743 		if (!skb)
3744 			goto out;
3745 		local->total_ps_buffered--;
3746 
3747 		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
3748 			struct ieee80211_hdr *hdr =
3749 				(struct ieee80211_hdr *) skb->data;
3750 			/* more buffered multicast/broadcast frames ==> set
3751 			 * MoreData flag in IEEE 802.11 header to inform PS
3752 			 * STAs */
3753 			hdr->frame_control |=
3754 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
3755 		}
3756 
3757 		if (sdata->vif.type == NL80211_IFTYPE_AP)
3758 			sdata = IEEE80211_DEV_TO_SUB_IF(skb->dev);
3759 		if (!ieee80211_tx_prepare(sdata, &tx, NULL, skb))
3760 			break;
3761 		dev_kfree_skb_any(skb);
3762 	}
3763 
3764 	info = IEEE80211_SKB_CB(skb);
3765 
3766 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
3767 	info->band = chanctx_conf->def.chan->band;
3768 
3769 	if (invoke_tx_handlers(&tx))
3770 		skb = NULL;
3771  out:
3772 	rcu_read_unlock();
3773 
3774 	return skb;
3775 }
3776 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
3777 
3778 int ieee80211_reserve_tid(struct ieee80211_sta *pubsta, u8 tid)
3779 {
3780 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
3781 	struct ieee80211_sub_if_data *sdata = sta->sdata;
3782 	struct ieee80211_local *local = sdata->local;
3783 	int ret;
3784 	u32 queues;
3785 
3786 	lockdep_assert_held(&local->sta_mtx);
3787 
3788 	/* only some cases are supported right now */
3789 	switch (sdata->vif.type) {
3790 	case NL80211_IFTYPE_STATION:
3791 	case NL80211_IFTYPE_AP:
3792 	case NL80211_IFTYPE_AP_VLAN:
3793 		break;
3794 	default:
3795 		WARN_ON(1);
3796 		return -EINVAL;
3797 	}
3798 
3799 	if (WARN_ON(tid >= IEEE80211_NUM_UPS))
3800 		return -EINVAL;
3801 
3802 	if (sta->reserved_tid == tid) {
3803 		ret = 0;
3804 		goto out;
3805 	}
3806 
3807 	if (sta->reserved_tid != IEEE80211_TID_UNRESERVED) {
3808 		sdata_err(sdata, "TID reservation already active\n");
3809 		ret = -EALREADY;
3810 		goto out;
3811 	}
3812 
3813 	ieee80211_stop_vif_queues(sdata->local, sdata,
3814 				  IEEE80211_QUEUE_STOP_REASON_RESERVE_TID);
3815 
3816 	synchronize_net();
3817 
3818 	/* Tear down BA sessions so we stop aggregating on this TID */
3819 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION)) {
3820 		set_sta_flag(sta, WLAN_STA_BLOCK_BA);
3821 		__ieee80211_stop_tx_ba_session(sta, tid,
3822 					       AGG_STOP_LOCAL_REQUEST);
3823 	}
3824 
3825 	queues = BIT(sdata->vif.hw_queue[ieee802_1d_to_ac[tid]]);
3826 	__ieee80211_flush_queues(local, sdata, queues, false);
3827 
3828 	sta->reserved_tid = tid;
3829 
3830 	ieee80211_wake_vif_queues(local, sdata,
3831 				  IEEE80211_QUEUE_STOP_REASON_RESERVE_TID);
3832 
3833 	if (ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION))
3834 		clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
3835 
3836 	ret = 0;
3837  out:
3838 	return ret;
3839 }
3840 EXPORT_SYMBOL(ieee80211_reserve_tid);
3841 
3842 void ieee80211_unreserve_tid(struct ieee80211_sta *pubsta, u8 tid)
3843 {
3844 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
3845 	struct ieee80211_sub_if_data *sdata = sta->sdata;
3846 
3847 	lockdep_assert_held(&sdata->local->sta_mtx);
3848 
3849 	/* only some cases are supported right now */
3850 	switch (sdata->vif.type) {
3851 	case NL80211_IFTYPE_STATION:
3852 	case NL80211_IFTYPE_AP:
3853 	case NL80211_IFTYPE_AP_VLAN:
3854 		break;
3855 	default:
3856 		WARN_ON(1);
3857 		return;
3858 	}
3859 
3860 	if (tid != sta->reserved_tid) {
3861 		sdata_err(sdata, "TID to unreserve (%d) isn't reserved\n", tid);
3862 		return;
3863 	}
3864 
3865 	sta->reserved_tid = IEEE80211_TID_UNRESERVED;
3866 }
3867 EXPORT_SYMBOL(ieee80211_unreserve_tid);
3868 
3869 void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
3870 				 struct sk_buff *skb, int tid,
3871 				 enum ieee80211_band band)
3872 {
3873 	int ac = ieee802_1d_to_ac[tid & 7];
3874 
3875 	skb_set_mac_header(skb, 0);
3876 	skb_set_network_header(skb, 0);
3877 	skb_set_transport_header(skb, 0);
3878 
3879 	skb_set_queue_mapping(skb, ac);
3880 	skb->priority = tid;
3881 
3882 	skb->dev = sdata->dev;
3883 
3884 	/*
3885 	 * The other path calling ieee80211_xmit is from the tasklet,
3886 	 * and while we can handle concurrent transmissions locking
3887 	 * requirements are that we do not come into tx with bhs on.
3888 	 */
3889 	local_bh_disable();
3890 	IEEE80211_SKB_CB(skb)->band = band;
3891 	ieee80211_xmit(sdata, NULL, skb);
3892 	local_bh_enable();
3893 }
3894