xref: /openbmc/linux/net/mac80211/tx.c (revision 97da55fc)
1 /*
2  * Copyright 2002-2005, Instant802 Networks, Inc.
3  * Copyright 2005-2006, Devicescape Software, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  *
12  * Transmit and frame generation functions.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/skbuff.h>
18 #include <linux/etherdevice.h>
19 #include <linux/bitmap.h>
20 #include <linux/rcupdate.h>
21 #include <linux/export.h>
22 #include <net/net_namespace.h>
23 #include <net/ieee80211_radiotap.h>
24 #include <net/cfg80211.h>
25 #include <net/mac80211.h>
26 #include <asm/unaligned.h>
27 
28 #include "ieee80211_i.h"
29 #include "driver-ops.h"
30 #include "led.h"
31 #include "mesh.h"
32 #include "wep.h"
33 #include "wpa.h"
34 #include "wme.h"
35 #include "rate.h"
36 
37 /* misc utils */
38 
39 static __le16 ieee80211_duration(struct ieee80211_tx_data *tx,
40 				 struct sk_buff *skb, int group_addr,
41 				 int next_frag_len)
42 {
43 	int rate, mrate, erp, dur, i;
44 	struct ieee80211_rate *txrate;
45 	struct ieee80211_local *local = tx->local;
46 	struct ieee80211_supported_band *sband;
47 	struct ieee80211_hdr *hdr;
48 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
49 
50 	/* assume HW handles this */
51 	if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS)
52 		return 0;
53 
54 	/* uh huh? */
55 	if (WARN_ON_ONCE(info->control.rates[0].idx < 0))
56 		return 0;
57 
58 	sband = local->hw.wiphy->bands[info->band];
59 	txrate = &sband->bitrates[info->control.rates[0].idx];
60 
61 	erp = txrate->flags & IEEE80211_RATE_ERP_G;
62 
63 	/*
64 	 * data and mgmt (except PS Poll):
65 	 * - during CFP: 32768
66 	 * - during contention period:
67 	 *   if addr1 is group address: 0
68 	 *   if more fragments = 0 and addr1 is individual address: time to
69 	 *      transmit one ACK plus SIFS
70 	 *   if more fragments = 1 and addr1 is individual address: time to
71 	 *      transmit next fragment plus 2 x ACK plus 3 x SIFS
72 	 *
73 	 * IEEE 802.11, 9.6:
74 	 * - control response frame (CTS or ACK) shall be transmitted using the
75 	 *   same rate as the immediately previous frame in the frame exchange
76 	 *   sequence, if this rate belongs to the PHY mandatory rates, or else
77 	 *   at the highest possible rate belonging to the PHY rates in the
78 	 *   BSSBasicRateSet
79 	 */
80 	hdr = (struct ieee80211_hdr *)skb->data;
81 	if (ieee80211_is_ctl(hdr->frame_control)) {
82 		/* TODO: These control frames are not currently sent by
83 		 * mac80211, but should they be implemented, this function
84 		 * needs to be updated to support duration field calculation.
85 		 *
86 		 * RTS: time needed to transmit pending data/mgmt frame plus
87 		 *    one CTS frame plus one ACK frame plus 3 x SIFS
88 		 * CTS: duration of immediately previous RTS minus time
89 		 *    required to transmit CTS and its SIFS
90 		 * ACK: 0 if immediately previous directed data/mgmt had
91 		 *    more=0, with more=1 duration in ACK frame is duration
92 		 *    from previous frame minus time needed to transmit ACK
93 		 *    and its SIFS
94 		 * PS Poll: BIT(15) | BIT(14) | aid
95 		 */
96 		return 0;
97 	}
98 
99 	/* data/mgmt */
100 	if (0 /* FIX: data/mgmt during CFP */)
101 		return cpu_to_le16(32768);
102 
103 	if (group_addr) /* Group address as the destination - no ACK */
104 		return 0;
105 
106 	/* Individual destination address:
107 	 * IEEE 802.11, Ch. 9.6 (after IEEE 802.11g changes)
108 	 * CTS and ACK frames shall be transmitted using the highest rate in
109 	 * basic rate set that is less than or equal to the rate of the
110 	 * immediately previous frame and that is using the same modulation
111 	 * (CCK or OFDM). If no basic rate set matches with these requirements,
112 	 * the highest mandatory rate of the PHY that is less than or equal to
113 	 * the rate of the previous frame is used.
114 	 * Mandatory rates for IEEE 802.11g PHY: 1, 2, 5.5, 11, 6, 12, 24 Mbps
115 	 */
116 	rate = -1;
117 	/* use lowest available if everything fails */
118 	mrate = sband->bitrates[0].bitrate;
119 	for (i = 0; i < sband->n_bitrates; i++) {
120 		struct ieee80211_rate *r = &sband->bitrates[i];
121 
122 		if (r->bitrate > txrate->bitrate)
123 			break;
124 
125 		if (tx->sdata->vif.bss_conf.basic_rates & BIT(i))
126 			rate = r->bitrate;
127 
128 		switch (sband->band) {
129 		case IEEE80211_BAND_2GHZ: {
130 			u32 flag;
131 			if (tx->sdata->flags & IEEE80211_SDATA_OPERATING_GMODE)
132 				flag = IEEE80211_RATE_MANDATORY_G;
133 			else
134 				flag = IEEE80211_RATE_MANDATORY_B;
135 			if (r->flags & flag)
136 				mrate = r->bitrate;
137 			break;
138 		}
139 		case IEEE80211_BAND_5GHZ:
140 			if (r->flags & IEEE80211_RATE_MANDATORY_A)
141 				mrate = r->bitrate;
142 			break;
143 		case IEEE80211_BAND_60GHZ:
144 			/* TODO, for now fall through */
145 		case IEEE80211_NUM_BANDS:
146 			WARN_ON(1);
147 			break;
148 		}
149 	}
150 	if (rate == -1) {
151 		/* No matching basic rate found; use highest suitable mandatory
152 		 * PHY rate */
153 		rate = mrate;
154 	}
155 
156 	/* Don't calculate ACKs for QoS Frames with NoAck Policy set */
157 	if (ieee80211_is_data_qos(hdr->frame_control) &&
158 	    *(ieee80211_get_qos_ctl(hdr)) & IEEE80211_QOS_CTL_ACK_POLICY_NOACK)
159 		dur = 0;
160 	else
161 		/* Time needed to transmit ACK
162 		 * (10 bytes + 4-byte FCS = 112 bits) plus SIFS; rounded up
163 		 * to closest integer */
164 		dur = ieee80211_frame_duration(sband->band, 10, rate, erp,
165 				tx->sdata->vif.bss_conf.use_short_preamble);
166 
167 	if (next_frag_len) {
168 		/* Frame is fragmented: duration increases with time needed to
169 		 * transmit next fragment plus ACK and 2 x SIFS. */
170 		dur *= 2; /* ACK + SIFS */
171 		/* next fragment */
172 		dur += ieee80211_frame_duration(sband->band, next_frag_len,
173 				txrate->bitrate, erp,
174 				tx->sdata->vif.bss_conf.use_short_preamble);
175 	}
176 
177 	return cpu_to_le16(dur);
178 }
179 
180 /* tx handlers */
181 static ieee80211_tx_result debug_noinline
182 ieee80211_tx_h_dynamic_ps(struct ieee80211_tx_data *tx)
183 {
184 	struct ieee80211_local *local = tx->local;
185 	struct ieee80211_if_managed *ifmgd;
186 
187 	/* driver doesn't support power save */
188 	if (!(local->hw.flags & IEEE80211_HW_SUPPORTS_PS))
189 		return TX_CONTINUE;
190 
191 	/* hardware does dynamic power save */
192 	if (local->hw.flags & IEEE80211_HW_SUPPORTS_DYNAMIC_PS)
193 		return TX_CONTINUE;
194 
195 	/* dynamic power save disabled */
196 	if (local->hw.conf.dynamic_ps_timeout <= 0)
197 		return TX_CONTINUE;
198 
199 	/* we are scanning, don't enable power save */
200 	if (local->scanning)
201 		return TX_CONTINUE;
202 
203 	if (!local->ps_sdata)
204 		return TX_CONTINUE;
205 
206 	/* No point if we're going to suspend */
207 	if (local->quiescing)
208 		return TX_CONTINUE;
209 
210 	/* dynamic ps is supported only in managed mode */
211 	if (tx->sdata->vif.type != NL80211_IFTYPE_STATION)
212 		return TX_CONTINUE;
213 
214 	ifmgd = &tx->sdata->u.mgd;
215 
216 	/*
217 	 * Don't wakeup from power save if u-apsd is enabled, voip ac has
218 	 * u-apsd enabled and the frame is in voip class. This effectively
219 	 * means that even if all access categories have u-apsd enabled, in
220 	 * practise u-apsd is only used with the voip ac. This is a
221 	 * workaround for the case when received voip class packets do not
222 	 * have correct qos tag for some reason, due the network or the
223 	 * peer application.
224 	 *
225 	 * Note: ifmgd->uapsd_queues access is racy here. If the value is
226 	 * changed via debugfs, user needs to reassociate manually to have
227 	 * everything in sync.
228 	 */
229 	if ((ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED) &&
230 	    (ifmgd->uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO) &&
231 	    skb_get_queue_mapping(tx->skb) == IEEE80211_AC_VO)
232 		return TX_CONTINUE;
233 
234 	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
235 		ieee80211_stop_queues_by_reason(&local->hw,
236 						IEEE80211_QUEUE_STOP_REASON_PS);
237 		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
238 		ieee80211_queue_work(&local->hw,
239 				     &local->dynamic_ps_disable_work);
240 	}
241 
242 	/* Don't restart the timer if we're not disassociated */
243 	if (!ifmgd->associated)
244 		return TX_CONTINUE;
245 
246 	mod_timer(&local->dynamic_ps_timer, jiffies +
247 		  msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
248 
249 	return TX_CONTINUE;
250 }
251 
252 static ieee80211_tx_result debug_noinline
253 ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
254 {
255 
256 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
257 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
258 	bool assoc = false;
259 
260 	if (unlikely(info->flags & IEEE80211_TX_CTL_INJECTED))
261 		return TX_CONTINUE;
262 
263 	if (unlikely(test_bit(SCAN_SW_SCANNING, &tx->local->scanning)) &&
264 	    test_bit(SDATA_STATE_OFFCHANNEL, &tx->sdata->state) &&
265 	    !ieee80211_is_probe_req(hdr->frame_control) &&
266 	    !ieee80211_is_nullfunc(hdr->frame_control))
267 		/*
268 		 * When software scanning only nullfunc frames (to notify
269 		 * the sleep state to the AP) and probe requests (for the
270 		 * active scan) are allowed, all other frames should not be
271 		 * sent and we should not get here, but if we do
272 		 * nonetheless, drop them to avoid sending them
273 		 * off-channel. See the link below and
274 		 * ieee80211_start_scan() for more.
275 		 *
276 		 * http://article.gmane.org/gmane.linux.kernel.wireless.general/30089
277 		 */
278 		return TX_DROP;
279 
280 	if (tx->sdata->vif.type == NL80211_IFTYPE_WDS)
281 		return TX_CONTINUE;
282 
283 	if (tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
284 		return TX_CONTINUE;
285 
286 	if (tx->flags & IEEE80211_TX_PS_BUFFERED)
287 		return TX_CONTINUE;
288 
289 	if (tx->sta)
290 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
291 
292 	if (likely(tx->flags & IEEE80211_TX_UNICAST)) {
293 		if (unlikely(!assoc &&
294 			     ieee80211_is_data(hdr->frame_control))) {
295 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
296 			sdata_info(tx->sdata,
297 				   "dropped data frame to not associated station %pM\n",
298 				   hdr->addr1);
299 #endif
300 			I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
301 			return TX_DROP;
302 		}
303 	} else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
304 			    ieee80211_is_data(hdr->frame_control) &&
305 			    !atomic_read(&tx->sdata->u.ap.num_mcast_sta))) {
306 		/*
307 		 * No associated STAs - no need to send multicast
308 		 * frames.
309 		 */
310 		return TX_DROP;
311 	}
312 
313 	return TX_CONTINUE;
314 }
315 
316 /* This function is called whenever the AP is about to exceed the maximum limit
317  * of buffered frames for power saving STAs. This situation should not really
318  * happen often during normal operation, so dropping the oldest buffered packet
319  * from each queue should be OK to make some room for new frames. */
320 static void purge_old_ps_buffers(struct ieee80211_local *local)
321 {
322 	int total = 0, purged = 0;
323 	struct sk_buff *skb;
324 	struct ieee80211_sub_if_data *sdata;
325 	struct sta_info *sta;
326 
327 	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
328 		struct ps_data *ps;
329 
330 		if (sdata->vif.type == NL80211_IFTYPE_AP)
331 			ps = &sdata->u.ap.ps;
332 		else if (ieee80211_vif_is_mesh(&sdata->vif))
333 			ps = &sdata->u.mesh.ps;
334 		else
335 			continue;
336 
337 		skb = skb_dequeue(&ps->bc_buf);
338 		if (skb) {
339 			purged++;
340 			dev_kfree_skb(skb);
341 		}
342 		total += skb_queue_len(&ps->bc_buf);
343 	}
344 
345 	/*
346 	 * Drop one frame from each station from the lowest-priority
347 	 * AC that has frames at all.
348 	 */
349 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
350 		int ac;
351 
352 		for (ac = IEEE80211_AC_BK; ac >= IEEE80211_AC_VO; ac--) {
353 			skb = skb_dequeue(&sta->ps_tx_buf[ac]);
354 			total += skb_queue_len(&sta->ps_tx_buf[ac]);
355 			if (skb) {
356 				purged++;
357 				ieee80211_free_txskb(&local->hw, skb);
358 				break;
359 			}
360 		}
361 	}
362 
363 	local->total_ps_buffered = total;
364 	ps_dbg_hw(&local->hw, "PS buffers full - purged %d frames\n", purged);
365 }
366 
367 static ieee80211_tx_result
368 ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
369 {
370 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
371 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
372 	struct ps_data *ps;
373 
374 	/*
375 	 * broadcast/multicast frame
376 	 *
377 	 * If any of the associated/peer stations is in power save mode,
378 	 * the frame is buffered to be sent after DTIM beacon frame.
379 	 * This is done either by the hardware or us.
380 	 */
381 
382 	/* powersaving STAs currently only in AP/VLAN/mesh mode */
383 	if (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
384 	    tx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
385 		if (!tx->sdata->bss)
386 			return TX_CONTINUE;
387 
388 		ps = &tx->sdata->bss->ps;
389 	} else if (ieee80211_vif_is_mesh(&tx->sdata->vif)) {
390 		ps = &tx->sdata->u.mesh.ps;
391 	} else {
392 		return TX_CONTINUE;
393 	}
394 
395 
396 	/* no buffering for ordered frames */
397 	if (ieee80211_has_order(hdr->frame_control))
398 		return TX_CONTINUE;
399 
400 	/* no stations in PS mode */
401 	if (!atomic_read(&ps->num_sta_ps))
402 		return TX_CONTINUE;
403 
404 	info->flags |= IEEE80211_TX_CTL_SEND_AFTER_DTIM;
405 	if (tx->local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
406 		info->hw_queue = tx->sdata->vif.cab_queue;
407 
408 	/* device releases frame after DTIM beacon */
409 	if (!(tx->local->hw.flags & IEEE80211_HW_HOST_BROADCAST_PS_BUFFERING))
410 		return TX_CONTINUE;
411 
412 	/* buffered in mac80211 */
413 	if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
414 		purge_old_ps_buffers(tx->local);
415 
416 	if (skb_queue_len(&ps->bc_buf) >= AP_MAX_BC_BUFFER) {
417 		ps_dbg(tx->sdata,
418 		       "BC TX buffer full - dropping the oldest frame\n");
419 		dev_kfree_skb(skb_dequeue(&ps->bc_buf));
420 	} else
421 		tx->local->total_ps_buffered++;
422 
423 	skb_queue_tail(&ps->bc_buf, tx->skb);
424 
425 	return TX_QUEUED;
426 }
427 
428 static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
429 			     struct sk_buff *skb)
430 {
431 	if (!ieee80211_is_mgmt(fc))
432 		return 0;
433 
434 	if (sta == NULL || !test_sta_flag(sta, WLAN_STA_MFP))
435 		return 0;
436 
437 	if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
438 					    skb->data))
439 		return 0;
440 
441 	return 1;
442 }
443 
444 static ieee80211_tx_result
445 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
446 {
447 	struct sta_info *sta = tx->sta;
448 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
449 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
450 	struct ieee80211_local *local = tx->local;
451 
452 	if (unlikely(!sta))
453 		return TX_CONTINUE;
454 
455 	if (unlikely((test_sta_flag(sta, WLAN_STA_PS_STA) ||
456 		      test_sta_flag(sta, WLAN_STA_PS_DRIVER)) &&
457 		     !(info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER))) {
458 		int ac = skb_get_queue_mapping(tx->skb);
459 
460 		/* only deauth, disassoc and action are bufferable MMPDUs */
461 		if (ieee80211_is_mgmt(hdr->frame_control) &&
462 		    !ieee80211_is_deauth(hdr->frame_control) &&
463 		    !ieee80211_is_disassoc(hdr->frame_control) &&
464 		    !ieee80211_is_action(hdr->frame_control)) {
465 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
466 			return TX_CONTINUE;
467 		}
468 
469 		ps_dbg(sta->sdata, "STA %pM aid %d: PS buffer for AC %d\n",
470 		       sta->sta.addr, sta->sta.aid, ac);
471 		if (tx->local->total_ps_buffered >= TOTAL_MAX_TX_BUFFER)
472 			purge_old_ps_buffers(tx->local);
473 		if (skb_queue_len(&sta->ps_tx_buf[ac]) >= STA_MAX_TX_BUFFER) {
474 			struct sk_buff *old = skb_dequeue(&sta->ps_tx_buf[ac]);
475 			ps_dbg(tx->sdata,
476 			       "STA %pM TX buffer for AC %d full - dropping oldest frame\n",
477 			       sta->sta.addr, ac);
478 			ieee80211_free_txskb(&local->hw, old);
479 		} else
480 			tx->local->total_ps_buffered++;
481 
482 		info->control.jiffies = jiffies;
483 		info->control.vif = &tx->sdata->vif;
484 		info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
485 		skb_queue_tail(&sta->ps_tx_buf[ac], tx->skb);
486 
487 		if (!timer_pending(&local->sta_cleanup))
488 			mod_timer(&local->sta_cleanup,
489 				  round_jiffies(jiffies +
490 						STA_INFO_CLEANUP_INTERVAL));
491 
492 		/*
493 		 * We queued up some frames, so the TIM bit might
494 		 * need to be set, recalculate it.
495 		 */
496 		sta_info_recalc_tim(sta);
497 
498 		return TX_QUEUED;
499 	} else if (unlikely(test_sta_flag(sta, WLAN_STA_PS_STA))) {
500 		ps_dbg(tx->sdata,
501 		       "STA %pM in PS mode, but polling/in SP -> send frame\n",
502 		       sta->sta.addr);
503 	}
504 
505 	return TX_CONTINUE;
506 }
507 
508 static ieee80211_tx_result debug_noinline
509 ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
510 {
511 	if (unlikely(tx->flags & IEEE80211_TX_PS_BUFFERED))
512 		return TX_CONTINUE;
513 
514 	if (tx->flags & IEEE80211_TX_UNICAST)
515 		return ieee80211_tx_h_unicast_ps_buf(tx);
516 	else
517 		return ieee80211_tx_h_multicast_ps_buf(tx);
518 }
519 
520 static ieee80211_tx_result debug_noinline
521 ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
522 {
523 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
524 
525 	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol &&
526 		     tx->sdata->control_port_no_encrypt))
527 		info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
528 
529 	return TX_CONTINUE;
530 }
531 
532 static ieee80211_tx_result debug_noinline
533 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
534 {
535 	struct ieee80211_key *key;
536 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
537 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
538 
539 	if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
540 		tx->key = NULL;
541 	else if (tx->sta && (key = rcu_dereference(tx->sta->ptk)))
542 		tx->key = key;
543 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
544 		 is_multicast_ether_addr(hdr->addr1) &&
545 		 ieee80211_is_robust_mgmt_frame(hdr) &&
546 		 (key = rcu_dereference(tx->sdata->default_mgmt_key)))
547 		tx->key = key;
548 	else if (is_multicast_ether_addr(hdr->addr1) &&
549 		 (key = rcu_dereference(tx->sdata->default_multicast_key)))
550 		tx->key = key;
551 	else if (!is_multicast_ether_addr(hdr->addr1) &&
552 		 (key = rcu_dereference(tx->sdata->default_unicast_key)))
553 		tx->key = key;
554 	else if (info->flags & IEEE80211_TX_CTL_INJECTED)
555 		tx->key = NULL;
556 	else if (!tx->sdata->drop_unencrypted)
557 		tx->key = NULL;
558 	else if (tx->skb->protocol == tx->sdata->control_port_protocol)
559 		tx->key = NULL;
560 	else if (ieee80211_is_robust_mgmt_frame(hdr) &&
561 		 !(ieee80211_is_action(hdr->frame_control) &&
562 		   tx->sta && test_sta_flag(tx->sta, WLAN_STA_MFP)))
563 		tx->key = NULL;
564 	else if (ieee80211_is_mgmt(hdr->frame_control) &&
565 		 !ieee80211_is_robust_mgmt_frame(hdr))
566 		tx->key = NULL;
567 	else {
568 		I802_DEBUG_INC(tx->local->tx_handlers_drop_unencrypted);
569 		return TX_DROP;
570 	}
571 
572 	if (tx->key) {
573 		bool skip_hw = false;
574 
575 		tx->key->tx_rx_count++;
576 		/* TODO: add threshold stuff again */
577 
578 		switch (tx->key->conf.cipher) {
579 		case WLAN_CIPHER_SUITE_WEP40:
580 		case WLAN_CIPHER_SUITE_WEP104:
581 		case WLAN_CIPHER_SUITE_TKIP:
582 			if (!ieee80211_is_data_present(hdr->frame_control))
583 				tx->key = NULL;
584 			break;
585 		case WLAN_CIPHER_SUITE_CCMP:
586 			if (!ieee80211_is_data_present(hdr->frame_control) &&
587 			    !ieee80211_use_mfp(hdr->frame_control, tx->sta,
588 					       tx->skb))
589 				tx->key = NULL;
590 			else
591 				skip_hw = (tx->key->conf.flags &
592 					   IEEE80211_KEY_FLAG_SW_MGMT_TX) &&
593 					ieee80211_is_mgmt(hdr->frame_control);
594 			break;
595 		case WLAN_CIPHER_SUITE_AES_CMAC:
596 			if (!ieee80211_is_mgmt(hdr->frame_control))
597 				tx->key = NULL;
598 			break;
599 		}
600 
601 		if (unlikely(tx->key && tx->key->flags & KEY_FLAG_TAINTED &&
602 			     !ieee80211_is_deauth(hdr->frame_control)))
603 			return TX_DROP;
604 
605 		if (!skip_hw && tx->key &&
606 		    tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
607 			info->control.hw_key = &tx->key->conf;
608 	}
609 
610 	return TX_CONTINUE;
611 }
612 
613 static ieee80211_tx_result debug_noinline
614 ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
615 {
616 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
617 	struct ieee80211_hdr *hdr = (void *)tx->skb->data;
618 	struct ieee80211_supported_band *sband;
619 	struct ieee80211_rate *rate;
620 	int i;
621 	u32 len;
622 	bool inval = false, rts = false, short_preamble = false;
623 	struct ieee80211_tx_rate_control txrc;
624 	bool assoc = false;
625 
626 	memset(&txrc, 0, sizeof(txrc));
627 
628 	sband = tx->local->hw.wiphy->bands[info->band];
629 
630 	len = min_t(u32, tx->skb->len + FCS_LEN,
631 			 tx->local->hw.wiphy->frag_threshold);
632 
633 	/* set up the tx rate control struct we give the RC algo */
634 	txrc.hw = &tx->local->hw;
635 	txrc.sband = sband;
636 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
637 	txrc.skb = tx->skb;
638 	txrc.reported_rate.idx = -1;
639 	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
640 	if (txrc.rate_idx_mask == (1 << sband->n_bitrates) - 1)
641 		txrc.max_rate_idx = -1;
642 	else
643 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
644 	memcpy(txrc.rate_idx_mcs_mask,
645 	       tx->sdata->rc_rateidx_mcs_mask[info->band],
646 	       sizeof(txrc.rate_idx_mcs_mask));
647 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
648 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
649 		    tx->sdata->vif.type == NL80211_IFTYPE_ADHOC);
650 
651 	/* set up RTS protection if desired */
652 	if (len > tx->local->hw.wiphy->rts_threshold) {
653 		txrc.rts = rts = true;
654 	}
655 
656 	/*
657 	 * Use short preamble if the BSS can handle it, but not for
658 	 * management frames unless we know the receiver can handle
659 	 * that -- the management frame might be to a station that
660 	 * just wants a probe response.
661 	 */
662 	if (tx->sdata->vif.bss_conf.use_short_preamble &&
663 	    (ieee80211_is_data(hdr->frame_control) ||
664 	     (tx->sta && test_sta_flag(tx->sta, WLAN_STA_SHORT_PREAMBLE))))
665 		txrc.short_preamble = short_preamble = true;
666 
667 	if (tx->sta)
668 		assoc = test_sta_flag(tx->sta, WLAN_STA_ASSOC);
669 
670 	/*
671 	 * Lets not bother rate control if we're associated and cannot
672 	 * talk to the sta. This should not happen.
673 	 */
674 	if (WARN(test_bit(SCAN_SW_SCANNING, &tx->local->scanning) && assoc &&
675 		 !rate_usable_index_exists(sband, &tx->sta->sta),
676 		 "%s: Dropped data frame as no usable bitrate found while "
677 		 "scanning and associated. Target station: "
678 		 "%pM on %d GHz band\n",
679 		 tx->sdata->name, hdr->addr1,
680 		 info->band ? 5 : 2))
681 		return TX_DROP;
682 
683 	/*
684 	 * If we're associated with the sta at this point we know we can at
685 	 * least send the frame at the lowest bit rate.
686 	 */
687 	rate_control_get_rate(tx->sdata, tx->sta, &txrc);
688 
689 	if (unlikely(info->control.rates[0].idx < 0))
690 		return TX_DROP;
691 
692 	if (txrc.reported_rate.idx < 0) {
693 		txrc.reported_rate = info->control.rates[0];
694 		if (tx->sta && ieee80211_is_data(hdr->frame_control))
695 			tx->sta->last_tx_rate = txrc.reported_rate;
696 	} else if (tx->sta)
697 		tx->sta->last_tx_rate = txrc.reported_rate;
698 
699 	if (unlikely(!info->control.rates[0].count))
700 		info->control.rates[0].count = 1;
701 
702 	if (WARN_ON_ONCE((info->control.rates[0].count > 1) &&
703 			 (info->flags & IEEE80211_TX_CTL_NO_ACK)))
704 		info->control.rates[0].count = 1;
705 
706 	if (is_multicast_ether_addr(hdr->addr1)) {
707 		/*
708 		 * XXX: verify the rate is in the basic rateset
709 		 */
710 		return TX_CONTINUE;
711 	}
712 
713 	/*
714 	 * set up the RTS/CTS rate as the fastest basic rate
715 	 * that is not faster than the data rate
716 	 *
717 	 * XXX: Should this check all retry rates?
718 	 */
719 	if (!(info->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
720 		s8 baserate = 0;
721 
722 		rate = &sband->bitrates[info->control.rates[0].idx];
723 
724 		for (i = 0; i < sband->n_bitrates; i++) {
725 			/* must be a basic rate */
726 			if (!(tx->sdata->vif.bss_conf.basic_rates & BIT(i)))
727 				continue;
728 			/* must not be faster than the data rate */
729 			if (sband->bitrates[i].bitrate > rate->bitrate)
730 				continue;
731 			/* maximum */
732 			if (sband->bitrates[baserate].bitrate <
733 			     sband->bitrates[i].bitrate)
734 				baserate = i;
735 		}
736 
737 		info->control.rts_cts_rate_idx = baserate;
738 	}
739 
740 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
741 		/*
742 		 * make sure there's no valid rate following
743 		 * an invalid one, just in case drivers don't
744 		 * take the API seriously to stop at -1.
745 		 */
746 		if (inval) {
747 			info->control.rates[i].idx = -1;
748 			continue;
749 		}
750 		if (info->control.rates[i].idx < 0) {
751 			inval = true;
752 			continue;
753 		}
754 
755 		/*
756 		 * For now assume MCS is already set up correctly, this
757 		 * needs to be fixed.
758 		 */
759 		if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) {
760 			WARN_ON(info->control.rates[i].idx > 76);
761 			continue;
762 		}
763 
764 		/* set up RTS protection if desired */
765 		if (rts)
766 			info->control.rates[i].flags |=
767 				IEEE80211_TX_RC_USE_RTS_CTS;
768 
769 		/* RC is busted */
770 		if (WARN_ON_ONCE(info->control.rates[i].idx >=
771 				 sband->n_bitrates)) {
772 			info->control.rates[i].idx = -1;
773 			continue;
774 		}
775 
776 		rate = &sband->bitrates[info->control.rates[i].idx];
777 
778 		/* set up short preamble */
779 		if (short_preamble &&
780 		    rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
781 			info->control.rates[i].flags |=
782 				IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
783 
784 		/* set up G protection */
785 		if (!rts && tx->sdata->vif.bss_conf.use_cts_prot &&
786 		    rate->flags & IEEE80211_RATE_ERP_G)
787 			info->control.rates[i].flags |=
788 				IEEE80211_TX_RC_USE_CTS_PROTECT;
789 	}
790 
791 	return TX_CONTINUE;
792 }
793 
794 static ieee80211_tx_result debug_noinline
795 ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
796 {
797 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
798 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
799 	u16 *seq;
800 	u8 *qc;
801 	int tid;
802 
803 	/*
804 	 * Packet injection may want to control the sequence
805 	 * number, if we have no matching interface then we
806 	 * neither assign one ourselves nor ask the driver to.
807 	 */
808 	if (unlikely(info->control.vif->type == NL80211_IFTYPE_MONITOR))
809 		return TX_CONTINUE;
810 
811 	if (unlikely(ieee80211_is_ctl(hdr->frame_control)))
812 		return TX_CONTINUE;
813 
814 	if (ieee80211_hdrlen(hdr->frame_control) < 24)
815 		return TX_CONTINUE;
816 
817 	if (ieee80211_is_qos_nullfunc(hdr->frame_control))
818 		return TX_CONTINUE;
819 
820 	/*
821 	 * Anything but QoS data that has a sequence number field
822 	 * (is long enough) gets a sequence number from the global
823 	 * counter.
824 	 */
825 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
826 		/* driver should assign sequence number */
827 		info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
828 		/* for pure STA mode without beacons, we can do it */
829 		hdr->seq_ctrl = cpu_to_le16(tx->sdata->sequence_number);
830 		tx->sdata->sequence_number += 0x10;
831 		return TX_CONTINUE;
832 	}
833 
834 	/*
835 	 * This should be true for injected/management frames only, for
836 	 * management frames we have set the IEEE80211_TX_CTL_ASSIGN_SEQ
837 	 * above since they are not QoS-data frames.
838 	 */
839 	if (!tx->sta)
840 		return TX_CONTINUE;
841 
842 	/* include per-STA, per-TID sequence counter */
843 
844 	qc = ieee80211_get_qos_ctl(hdr);
845 	tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
846 	seq = &tx->sta->tid_seq[tid];
847 
848 	hdr->seq_ctrl = cpu_to_le16(*seq);
849 
850 	/* Increase the sequence number. */
851 	*seq = (*seq + 0x10) & IEEE80211_SCTL_SEQ;
852 
853 	return TX_CONTINUE;
854 }
855 
856 static int ieee80211_fragment(struct ieee80211_tx_data *tx,
857 			      struct sk_buff *skb, int hdrlen,
858 			      int frag_threshold)
859 {
860 	struct ieee80211_local *local = tx->local;
861 	struct ieee80211_tx_info *info;
862 	struct sk_buff *tmp;
863 	int per_fragm = frag_threshold - hdrlen - FCS_LEN;
864 	int pos = hdrlen + per_fragm;
865 	int rem = skb->len - hdrlen - per_fragm;
866 
867 	if (WARN_ON(rem < 0))
868 		return -EINVAL;
869 
870 	/* first fragment was already added to queue by caller */
871 
872 	while (rem) {
873 		int fraglen = per_fragm;
874 
875 		if (fraglen > rem)
876 			fraglen = rem;
877 		rem -= fraglen;
878 		tmp = dev_alloc_skb(local->tx_headroom +
879 				    frag_threshold +
880 				    IEEE80211_ENCRYPT_HEADROOM +
881 				    IEEE80211_ENCRYPT_TAILROOM);
882 		if (!tmp)
883 			return -ENOMEM;
884 
885 		__skb_queue_tail(&tx->skbs, tmp);
886 
887 		skb_reserve(tmp, local->tx_headroom +
888 				 IEEE80211_ENCRYPT_HEADROOM);
889 		/* copy control information */
890 		memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
891 
892 		info = IEEE80211_SKB_CB(tmp);
893 		info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
894 				 IEEE80211_TX_CTL_FIRST_FRAGMENT);
895 
896 		if (rem)
897 			info->flags |= IEEE80211_TX_CTL_MORE_FRAMES;
898 
899 		skb_copy_queue_mapping(tmp, skb);
900 		tmp->priority = skb->priority;
901 		tmp->dev = skb->dev;
902 
903 		/* copy header and data */
904 		memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
905 		memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
906 
907 		pos += fraglen;
908 	}
909 
910 	/* adjust first fragment's length */
911 	skb->len = hdrlen + per_fragm;
912 	return 0;
913 }
914 
915 static ieee80211_tx_result debug_noinline
916 ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
917 {
918 	struct sk_buff *skb = tx->skb;
919 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
920 	struct ieee80211_hdr *hdr = (void *)skb->data;
921 	int frag_threshold = tx->local->hw.wiphy->frag_threshold;
922 	int hdrlen;
923 	int fragnum;
924 
925 	/* no matter what happens, tx->skb moves to tx->skbs */
926 	__skb_queue_tail(&tx->skbs, skb);
927 	tx->skb = NULL;
928 
929 	if (info->flags & IEEE80211_TX_CTL_DONTFRAG)
930 		return TX_CONTINUE;
931 
932 	if (tx->local->ops->set_frag_threshold)
933 		return TX_CONTINUE;
934 
935 	/*
936 	 * Warn when submitting a fragmented A-MPDU frame and drop it.
937 	 * This scenario is handled in ieee80211_tx_prepare but extra
938 	 * caution taken here as fragmented ampdu may cause Tx stop.
939 	 */
940 	if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
941 		return TX_DROP;
942 
943 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
944 
945 	/* internal error, why isn't DONTFRAG set? */
946 	if (WARN_ON(skb->len + FCS_LEN <= frag_threshold))
947 		return TX_DROP;
948 
949 	/*
950 	 * Now fragment the frame. This will allocate all the fragments and
951 	 * chain them (using skb as the first fragment) to skb->next.
952 	 * During transmission, we will remove the successfully transmitted
953 	 * fragments from this list. When the low-level driver rejects one
954 	 * of the fragments then we will simply pretend to accept the skb
955 	 * but store it away as pending.
956 	 */
957 	if (ieee80211_fragment(tx, skb, hdrlen, frag_threshold))
958 		return TX_DROP;
959 
960 	/* update duration/seq/flags of fragments */
961 	fragnum = 0;
962 
963 	skb_queue_walk(&tx->skbs, skb) {
964 		const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
965 
966 		hdr = (void *)skb->data;
967 		info = IEEE80211_SKB_CB(skb);
968 
969 		if (!skb_queue_is_last(&tx->skbs, skb)) {
970 			hdr->frame_control |= morefrags;
971 			/*
972 			 * No multi-rate retries for fragmented frames, that
973 			 * would completely throw off the NAV at other STAs.
974 			 */
975 			info->control.rates[1].idx = -1;
976 			info->control.rates[2].idx = -1;
977 			info->control.rates[3].idx = -1;
978 			BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 4);
979 			info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
980 		} else {
981 			hdr->frame_control &= ~morefrags;
982 		}
983 		hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
984 		fragnum++;
985 	}
986 
987 	return TX_CONTINUE;
988 }
989 
990 static ieee80211_tx_result debug_noinline
991 ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
992 {
993 	struct sk_buff *skb;
994 
995 	if (!tx->sta)
996 		return TX_CONTINUE;
997 
998 	tx->sta->tx_packets++;
999 	skb_queue_walk(&tx->skbs, skb) {
1000 		tx->sta->tx_fragments++;
1001 		tx->sta->tx_bytes += skb->len;
1002 	}
1003 
1004 	return TX_CONTINUE;
1005 }
1006 
1007 static ieee80211_tx_result debug_noinline
1008 ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx)
1009 {
1010 	if (!tx->key)
1011 		return TX_CONTINUE;
1012 
1013 	switch (tx->key->conf.cipher) {
1014 	case WLAN_CIPHER_SUITE_WEP40:
1015 	case WLAN_CIPHER_SUITE_WEP104:
1016 		return ieee80211_crypto_wep_encrypt(tx);
1017 	case WLAN_CIPHER_SUITE_TKIP:
1018 		return ieee80211_crypto_tkip_encrypt(tx);
1019 	case WLAN_CIPHER_SUITE_CCMP:
1020 		return ieee80211_crypto_ccmp_encrypt(tx);
1021 	case WLAN_CIPHER_SUITE_AES_CMAC:
1022 		return ieee80211_crypto_aes_cmac_encrypt(tx);
1023 	default:
1024 		return ieee80211_crypto_hw_encrypt(tx);
1025 	}
1026 
1027 	return TX_DROP;
1028 }
1029 
1030 static ieee80211_tx_result debug_noinline
1031 ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
1032 {
1033 	struct sk_buff *skb;
1034 	struct ieee80211_hdr *hdr;
1035 	int next_len;
1036 	bool group_addr;
1037 
1038 	skb_queue_walk(&tx->skbs, skb) {
1039 		hdr = (void *) skb->data;
1040 		if (unlikely(ieee80211_is_pspoll(hdr->frame_control)))
1041 			break; /* must not overwrite AID */
1042 		if (!skb_queue_is_last(&tx->skbs, skb)) {
1043 			struct sk_buff *next = skb_queue_next(&tx->skbs, skb);
1044 			next_len = next->len;
1045 		} else
1046 			next_len = 0;
1047 		group_addr = is_multicast_ether_addr(hdr->addr1);
1048 
1049 		hdr->duration_id =
1050 			ieee80211_duration(tx, skb, group_addr, next_len);
1051 	}
1052 
1053 	return TX_CONTINUE;
1054 }
1055 
1056 /* actual transmit path */
1057 
1058 static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx,
1059 				  struct sk_buff *skb,
1060 				  struct ieee80211_tx_info *info,
1061 				  struct tid_ampdu_tx *tid_tx,
1062 				  int tid)
1063 {
1064 	bool queued = false;
1065 	bool reset_agg_timer = false;
1066 	struct sk_buff *purge_skb = NULL;
1067 
1068 	if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1069 		info->flags |= IEEE80211_TX_CTL_AMPDU;
1070 		reset_agg_timer = true;
1071 	} else if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
1072 		/*
1073 		 * nothing -- this aggregation session is being started
1074 		 * but that might still fail with the driver
1075 		 */
1076 	} else {
1077 		spin_lock(&tx->sta->lock);
1078 		/*
1079 		 * Need to re-check now, because we may get here
1080 		 *
1081 		 *  1) in the window during which the setup is actually
1082 		 *     already done, but not marked yet because not all
1083 		 *     packets are spliced over to the driver pending
1084 		 *     queue yet -- if this happened we acquire the lock
1085 		 *     either before or after the splice happens, but
1086 		 *     need to recheck which of these cases happened.
1087 		 *
1088 		 *  2) during session teardown, if the OPERATIONAL bit
1089 		 *     was cleared due to the teardown but the pointer
1090 		 *     hasn't been assigned NULL yet (or we loaded it
1091 		 *     before it was assigned) -- in this case it may
1092 		 *     now be NULL which means we should just let the
1093 		 *     packet pass through because splicing the frames
1094 		 *     back is already done.
1095 		 */
1096 		tid_tx = rcu_dereference_protected_tid_tx(tx->sta, tid);
1097 
1098 		if (!tid_tx) {
1099 			/* do nothing, let packet pass through */
1100 		} else if (test_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state)) {
1101 			info->flags |= IEEE80211_TX_CTL_AMPDU;
1102 			reset_agg_timer = true;
1103 		} else {
1104 			queued = true;
1105 			info->control.vif = &tx->sdata->vif;
1106 			info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1107 			__skb_queue_tail(&tid_tx->pending, skb);
1108 			if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER)
1109 				purge_skb = __skb_dequeue(&tid_tx->pending);
1110 		}
1111 		spin_unlock(&tx->sta->lock);
1112 
1113 		if (purge_skb)
1114 			ieee80211_free_txskb(&tx->local->hw, purge_skb);
1115 	}
1116 
1117 	/* reset session timer */
1118 	if (reset_agg_timer && tid_tx->timeout)
1119 		tid_tx->last_tx = jiffies;
1120 
1121 	return queued;
1122 }
1123 
1124 /*
1125  * initialises @tx
1126  */
1127 static ieee80211_tx_result
1128 ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata,
1129 		     struct ieee80211_tx_data *tx,
1130 		     struct sk_buff *skb)
1131 {
1132 	struct ieee80211_local *local = sdata->local;
1133 	struct ieee80211_hdr *hdr;
1134 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1135 	int tid;
1136 	u8 *qc;
1137 
1138 	memset(tx, 0, sizeof(*tx));
1139 	tx->skb = skb;
1140 	tx->local = local;
1141 	tx->sdata = sdata;
1142 	__skb_queue_head_init(&tx->skbs);
1143 
1144 	/*
1145 	 * If this flag is set to true anywhere, and we get here,
1146 	 * we are doing the needed processing, so remove the flag
1147 	 * now.
1148 	 */
1149 	info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
1150 
1151 	hdr = (struct ieee80211_hdr *) skb->data;
1152 
1153 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1154 		tx->sta = rcu_dereference(sdata->u.vlan.sta);
1155 		if (!tx->sta && sdata->dev->ieee80211_ptr->use_4addr)
1156 			return TX_DROP;
1157 	} else if (info->flags & IEEE80211_TX_CTL_INJECTED ||
1158 		   tx->sdata->control_port_protocol == tx->skb->protocol) {
1159 		tx->sta = sta_info_get_bss(sdata, hdr->addr1);
1160 	}
1161 	if (!tx->sta)
1162 		tx->sta = sta_info_get(sdata, hdr->addr1);
1163 
1164 	if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
1165 	    !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
1166 	    (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) &&
1167 	    !(local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) {
1168 		struct tid_ampdu_tx *tid_tx;
1169 
1170 		qc = ieee80211_get_qos_ctl(hdr);
1171 		tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
1172 
1173 		tid_tx = rcu_dereference(tx->sta->ampdu_mlme.tid_tx[tid]);
1174 		if (tid_tx) {
1175 			bool queued;
1176 
1177 			queued = ieee80211_tx_prep_agg(tx, skb, info,
1178 						       tid_tx, tid);
1179 
1180 			if (unlikely(queued))
1181 				return TX_QUEUED;
1182 		}
1183 	}
1184 
1185 	if (is_multicast_ether_addr(hdr->addr1)) {
1186 		tx->flags &= ~IEEE80211_TX_UNICAST;
1187 		info->flags |= IEEE80211_TX_CTL_NO_ACK;
1188 	} else
1189 		tx->flags |= IEEE80211_TX_UNICAST;
1190 
1191 	if (!(info->flags & IEEE80211_TX_CTL_DONTFRAG)) {
1192 		if (!(tx->flags & IEEE80211_TX_UNICAST) ||
1193 		    skb->len + FCS_LEN <= local->hw.wiphy->frag_threshold ||
1194 		    info->flags & IEEE80211_TX_CTL_AMPDU)
1195 			info->flags |= IEEE80211_TX_CTL_DONTFRAG;
1196 	}
1197 
1198 	if (!tx->sta)
1199 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1200 	else if (test_and_clear_sta_flag(tx->sta, WLAN_STA_CLEAR_PS_FILT))
1201 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1202 
1203 	info->flags |= IEEE80211_TX_CTL_FIRST_FRAGMENT;
1204 
1205 	return TX_CONTINUE;
1206 }
1207 
1208 static bool ieee80211_tx_frags(struct ieee80211_local *local,
1209 			       struct ieee80211_vif *vif,
1210 			       struct ieee80211_sta *sta,
1211 			       struct sk_buff_head *skbs,
1212 			       bool txpending)
1213 {
1214 	struct ieee80211_tx_control control;
1215 	struct sk_buff *skb, *tmp;
1216 	unsigned long flags;
1217 
1218 	skb_queue_walk_safe(skbs, skb, tmp) {
1219 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1220 		int q = info->hw_queue;
1221 
1222 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1223 		if (WARN_ON_ONCE(q >= local->hw.queues)) {
1224 			__skb_unlink(skb, skbs);
1225 			ieee80211_free_txskb(&local->hw, skb);
1226 			continue;
1227 		}
1228 #endif
1229 
1230 		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
1231 		if (local->queue_stop_reasons[q] ||
1232 		    (!txpending && !skb_queue_empty(&local->pending[q]))) {
1233 			if (unlikely(info->flags &
1234 				     IEEE80211_TX_INTFL_OFFCHAN_TX_OK)) {
1235 				if (local->queue_stop_reasons[q] &
1236 				    ~BIT(IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL)) {
1237 					/*
1238 					 * Drop off-channel frames if queues
1239 					 * are stopped for any reason other
1240 					 * than off-channel operation. Never
1241 					 * queue them.
1242 					 */
1243 					spin_unlock_irqrestore(
1244 						&local->queue_stop_reason_lock,
1245 						flags);
1246 					ieee80211_purge_tx_queue(&local->hw,
1247 								 skbs);
1248 					return true;
1249 				}
1250 			} else {
1251 
1252 				/*
1253 				 * Since queue is stopped, queue up frames for
1254 				 * later transmission from the tx-pending
1255 				 * tasklet when the queue is woken again.
1256 				 */
1257 				if (txpending)
1258 					skb_queue_splice_init(skbs,
1259 							      &local->pending[q]);
1260 				else
1261 					skb_queue_splice_tail_init(skbs,
1262 								   &local->pending[q]);
1263 
1264 				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
1265 						       flags);
1266 				return false;
1267 			}
1268 		}
1269 		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
1270 
1271 		info->control.vif = vif;
1272 		control.sta = sta;
1273 
1274 		__skb_unlink(skb, skbs);
1275 		drv_tx(local, &control, skb);
1276 	}
1277 
1278 	return true;
1279 }
1280 
1281 /*
1282  * Returns false if the frame couldn't be transmitted but was queued instead.
1283  */
1284 static bool __ieee80211_tx(struct ieee80211_local *local,
1285 			   struct sk_buff_head *skbs, int led_len,
1286 			   struct sta_info *sta, bool txpending)
1287 {
1288 	struct ieee80211_tx_info *info;
1289 	struct ieee80211_sub_if_data *sdata;
1290 	struct ieee80211_vif *vif;
1291 	struct ieee80211_sta *pubsta;
1292 	struct sk_buff *skb;
1293 	bool result = true;
1294 	__le16 fc;
1295 
1296 	if (WARN_ON(skb_queue_empty(skbs)))
1297 		return true;
1298 
1299 	skb = skb_peek(skbs);
1300 	fc = ((struct ieee80211_hdr *)skb->data)->frame_control;
1301 	info = IEEE80211_SKB_CB(skb);
1302 	sdata = vif_to_sdata(info->control.vif);
1303 	if (sta && !sta->uploaded)
1304 		sta = NULL;
1305 
1306 	if (sta)
1307 		pubsta = &sta->sta;
1308 	else
1309 		pubsta = NULL;
1310 
1311 	switch (sdata->vif.type) {
1312 	case NL80211_IFTYPE_MONITOR:
1313 		sdata = rcu_dereference(local->monitor_sdata);
1314 		if (sdata) {
1315 			vif = &sdata->vif;
1316 			info->hw_queue =
1317 				vif->hw_queue[skb_get_queue_mapping(skb)];
1318 		} else if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL) {
1319 			dev_kfree_skb(skb);
1320 			return true;
1321 		} else
1322 			vif = NULL;
1323 		break;
1324 	case NL80211_IFTYPE_AP_VLAN:
1325 		sdata = container_of(sdata->bss,
1326 				     struct ieee80211_sub_if_data, u.ap);
1327 		/* fall through */
1328 	default:
1329 		vif = &sdata->vif;
1330 		break;
1331 	}
1332 
1333 	result = ieee80211_tx_frags(local, vif, pubsta, skbs,
1334 				    txpending);
1335 
1336 	ieee80211_tpt_led_trig_tx(local, fc, led_len);
1337 	ieee80211_led_tx(local, 1);
1338 
1339 	WARN_ON_ONCE(!skb_queue_empty(skbs));
1340 
1341 	return result;
1342 }
1343 
1344 /*
1345  * Invoke TX handlers, return 0 on success and non-zero if the
1346  * frame was dropped or queued.
1347  */
1348 static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
1349 {
1350 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
1351 	ieee80211_tx_result res = TX_DROP;
1352 
1353 #define CALL_TXH(txh) \
1354 	do {				\
1355 		res = txh(tx);		\
1356 		if (res != TX_CONTINUE)	\
1357 			goto txh_done;	\
1358 	} while (0)
1359 
1360 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
1361 	CALL_TXH(ieee80211_tx_h_check_assoc);
1362 	CALL_TXH(ieee80211_tx_h_ps_buf);
1363 	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
1364 	CALL_TXH(ieee80211_tx_h_select_key);
1365 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1366 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
1367 
1368 	if (unlikely(info->flags & IEEE80211_TX_INTFL_RETRANSMISSION)) {
1369 		__skb_queue_tail(&tx->skbs, tx->skb);
1370 		tx->skb = NULL;
1371 		goto txh_done;
1372 	}
1373 
1374 	CALL_TXH(ieee80211_tx_h_michael_mic_add);
1375 	CALL_TXH(ieee80211_tx_h_sequence);
1376 	CALL_TXH(ieee80211_tx_h_fragment);
1377 	/* handlers after fragment must be aware of tx info fragmentation! */
1378 	CALL_TXH(ieee80211_tx_h_stats);
1379 	CALL_TXH(ieee80211_tx_h_encrypt);
1380 	if (!(tx->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL))
1381 		CALL_TXH(ieee80211_tx_h_calculate_duration);
1382 #undef CALL_TXH
1383 
1384  txh_done:
1385 	if (unlikely(res == TX_DROP)) {
1386 		I802_DEBUG_INC(tx->local->tx_handlers_drop);
1387 		if (tx->skb)
1388 			ieee80211_free_txskb(&tx->local->hw, tx->skb);
1389 		else
1390 			ieee80211_purge_tx_queue(&tx->local->hw, &tx->skbs);
1391 		return -1;
1392 	} else if (unlikely(res == TX_QUEUED)) {
1393 		I802_DEBUG_INC(tx->local->tx_handlers_queued);
1394 		return -1;
1395 	}
1396 
1397 	return 0;
1398 }
1399 
1400 /*
1401  * Returns false if the frame couldn't be transmitted but was queued instead.
1402  */
1403 static bool ieee80211_tx(struct ieee80211_sub_if_data *sdata,
1404 			 struct sk_buff *skb, bool txpending,
1405 			 enum ieee80211_band band)
1406 {
1407 	struct ieee80211_local *local = sdata->local;
1408 	struct ieee80211_tx_data tx;
1409 	ieee80211_tx_result res_prepare;
1410 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1411 	bool result = true;
1412 	int led_len;
1413 
1414 	if (unlikely(skb->len < 10)) {
1415 		dev_kfree_skb(skb);
1416 		return true;
1417 	}
1418 
1419 	/* initialises tx */
1420 	led_len = skb->len;
1421 	res_prepare = ieee80211_tx_prepare(sdata, &tx, skb);
1422 
1423 	if (unlikely(res_prepare == TX_DROP)) {
1424 		ieee80211_free_txskb(&local->hw, skb);
1425 		return true;
1426 	} else if (unlikely(res_prepare == TX_QUEUED)) {
1427 		return true;
1428 	}
1429 
1430 	info->band = band;
1431 
1432 	/* set up hw_queue value early */
1433 	if (!(info->flags & IEEE80211_TX_CTL_TX_OFFCHAN) ||
1434 	    !(local->hw.flags & IEEE80211_HW_QUEUE_CONTROL))
1435 		info->hw_queue =
1436 			sdata->vif.hw_queue[skb_get_queue_mapping(skb)];
1437 
1438 	if (!invoke_tx_handlers(&tx))
1439 		result = __ieee80211_tx(local, &tx.skbs, led_len,
1440 					tx.sta, txpending);
1441 
1442 	return result;
1443 }
1444 
1445 /* device xmit handlers */
1446 
1447 static int ieee80211_skb_resize(struct ieee80211_sub_if_data *sdata,
1448 				struct sk_buff *skb,
1449 				int head_need, bool may_encrypt)
1450 {
1451 	struct ieee80211_local *local = sdata->local;
1452 	int tail_need = 0;
1453 
1454 	if (may_encrypt && sdata->crypto_tx_tailroom_needed_cnt) {
1455 		tail_need = IEEE80211_ENCRYPT_TAILROOM;
1456 		tail_need -= skb_tailroom(skb);
1457 		tail_need = max_t(int, tail_need, 0);
1458 	}
1459 
1460 	if (skb_cloned(skb))
1461 		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
1462 	else if (head_need || tail_need)
1463 		I802_DEBUG_INC(local->tx_expand_skb_head);
1464 	else
1465 		return 0;
1466 
1467 	if (pskb_expand_head(skb, head_need, tail_need, GFP_ATOMIC)) {
1468 		wiphy_debug(local->hw.wiphy,
1469 			    "failed to reallocate TX buffer\n");
1470 		return -ENOMEM;
1471 	}
1472 
1473 	return 0;
1474 }
1475 
1476 void ieee80211_xmit(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
1477 		    enum ieee80211_band band)
1478 {
1479 	struct ieee80211_local *local = sdata->local;
1480 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1481 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1482 	int headroom;
1483 	bool may_encrypt;
1484 
1485 	may_encrypt = !(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT);
1486 
1487 	headroom = local->tx_headroom;
1488 	if (may_encrypt)
1489 		headroom += IEEE80211_ENCRYPT_HEADROOM;
1490 	headroom -= skb_headroom(skb);
1491 	headroom = max_t(int, 0, headroom);
1492 
1493 	if (ieee80211_skb_resize(sdata, skb, headroom, may_encrypt)) {
1494 		ieee80211_free_txskb(&local->hw, skb);
1495 		return;
1496 	}
1497 
1498 	hdr = (struct ieee80211_hdr *) skb->data;
1499 	info->control.vif = &sdata->vif;
1500 
1501 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
1502 		if (ieee80211_is_data(hdr->frame_control) &&
1503 		    is_unicast_ether_addr(hdr->addr1)) {
1504 			if (mesh_nexthop_resolve(sdata, skb))
1505 				return; /* skb queued: don't free */
1506 		} else {
1507 			ieee80211_mps_set_frame_flags(sdata, NULL, hdr);
1508 		}
1509 	}
1510 
1511 	ieee80211_set_qos_hdr(sdata, skb);
1512 	ieee80211_tx(sdata, skb, false, band);
1513 }
1514 
1515 static bool ieee80211_parse_tx_radiotap(struct sk_buff *skb)
1516 {
1517 	struct ieee80211_radiotap_iterator iterator;
1518 	struct ieee80211_radiotap_header *rthdr =
1519 		(struct ieee80211_radiotap_header *) skb->data;
1520 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1521 	int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len,
1522 						   NULL);
1523 	u16 txflags;
1524 
1525 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
1526 		       IEEE80211_TX_CTL_DONTFRAG;
1527 
1528 	/*
1529 	 * for every radiotap entry that is present
1530 	 * (ieee80211_radiotap_iterator_next returns -ENOENT when no more
1531 	 * entries present, or -EINVAL on error)
1532 	 */
1533 
1534 	while (!ret) {
1535 		ret = ieee80211_radiotap_iterator_next(&iterator);
1536 
1537 		if (ret)
1538 			continue;
1539 
1540 		/* see if this argument is something we can use */
1541 		switch (iterator.this_arg_index) {
1542 		/*
1543 		 * You must take care when dereferencing iterator.this_arg
1544 		 * for multibyte types... the pointer is not aligned.  Use
1545 		 * get_unaligned((type *)iterator.this_arg) to dereference
1546 		 * iterator.this_arg for type "type" safely on all arches.
1547 		*/
1548 		case IEEE80211_RADIOTAP_FLAGS:
1549 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FCS) {
1550 				/*
1551 				 * this indicates that the skb we have been
1552 				 * handed has the 32-bit FCS CRC at the end...
1553 				 * we should react to that by snipping it off
1554 				 * because it will be recomputed and added
1555 				 * on transmission
1556 				 */
1557 				if (skb->len < (iterator._max_length + FCS_LEN))
1558 					return false;
1559 
1560 				skb_trim(skb, skb->len - FCS_LEN);
1561 			}
1562 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_WEP)
1563 				info->flags &= ~IEEE80211_TX_INTFL_DONT_ENCRYPT;
1564 			if (*iterator.this_arg & IEEE80211_RADIOTAP_F_FRAG)
1565 				info->flags &= ~IEEE80211_TX_CTL_DONTFRAG;
1566 			break;
1567 
1568 		case IEEE80211_RADIOTAP_TX_FLAGS:
1569 			txflags = get_unaligned_le16(iterator.this_arg);
1570 			if (txflags & IEEE80211_RADIOTAP_F_TX_NOACK)
1571 				info->flags |= IEEE80211_TX_CTL_NO_ACK;
1572 			break;
1573 
1574 		/*
1575 		 * Please update the file
1576 		 * Documentation/networking/mac80211-injection.txt
1577 		 * when parsing new fields here.
1578 		 */
1579 
1580 		default:
1581 			break;
1582 		}
1583 	}
1584 
1585 	if (ret != -ENOENT) /* ie, if we didn't simply run out of fields */
1586 		return false;
1587 
1588 	/*
1589 	 * remove the radiotap header
1590 	 * iterator->_max_length was sanity-checked against
1591 	 * skb->len by iterator init
1592 	 */
1593 	skb_pull(skb, iterator._max_length);
1594 
1595 	return true;
1596 }
1597 
1598 netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb,
1599 					 struct net_device *dev)
1600 {
1601 	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
1602 	struct ieee80211_chanctx_conf *chanctx_conf;
1603 	struct ieee80211_channel *chan;
1604 	struct ieee80211_radiotap_header *prthdr =
1605 		(struct ieee80211_radiotap_header *)skb->data;
1606 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1607 	struct ieee80211_hdr *hdr;
1608 	struct ieee80211_sub_if_data *tmp_sdata, *sdata;
1609 	u16 len_rthdr;
1610 	int hdrlen;
1611 
1612 	/* check for not even having the fixed radiotap header part */
1613 	if (unlikely(skb->len < sizeof(struct ieee80211_radiotap_header)))
1614 		goto fail; /* too short to be possibly valid */
1615 
1616 	/* is it a header version we can trust to find length from? */
1617 	if (unlikely(prthdr->it_version))
1618 		goto fail; /* only version 0 is supported */
1619 
1620 	/* then there must be a radiotap header with a length we can use */
1621 	len_rthdr = ieee80211_get_radiotap_len(skb->data);
1622 
1623 	/* does the skb contain enough to deliver on the alleged length? */
1624 	if (unlikely(skb->len < len_rthdr))
1625 		goto fail; /* skb too short for claimed rt header extent */
1626 
1627 	/*
1628 	 * fix up the pointers accounting for the radiotap
1629 	 * header still being in there.  We are being given
1630 	 * a precooked IEEE80211 header so no need for
1631 	 * normal processing
1632 	 */
1633 	skb_set_mac_header(skb, len_rthdr);
1634 	/*
1635 	 * these are just fixed to the end of the rt area since we
1636 	 * don't have any better information and at this point, nobody cares
1637 	 */
1638 	skb_set_network_header(skb, len_rthdr);
1639 	skb_set_transport_header(skb, len_rthdr);
1640 
1641 	if (skb->len < len_rthdr + 2)
1642 		goto fail;
1643 
1644 	hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
1645 	hdrlen = ieee80211_hdrlen(hdr->frame_control);
1646 
1647 	if (skb->len < len_rthdr + hdrlen)
1648 		goto fail;
1649 
1650 	/*
1651 	 * Initialize skb->protocol if the injected frame is a data frame
1652 	 * carrying a rfc1042 header
1653 	 */
1654 	if (ieee80211_is_data(hdr->frame_control) &&
1655 	    skb->len >= len_rthdr + hdrlen + sizeof(rfc1042_header) + 2) {
1656 		u8 *payload = (u8 *)hdr + hdrlen;
1657 
1658 		if (ether_addr_equal(payload, rfc1042_header))
1659 			skb->protocol = cpu_to_be16((payload[6] << 8) |
1660 						    payload[7]);
1661 	}
1662 
1663 	memset(info, 0, sizeof(*info));
1664 
1665 	info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS |
1666 		      IEEE80211_TX_CTL_INJECTED;
1667 
1668 	/* process and remove the injection radiotap header */
1669 	if (!ieee80211_parse_tx_radiotap(skb))
1670 		goto fail;
1671 
1672 	rcu_read_lock();
1673 
1674 	/*
1675 	 * We process outgoing injected frames that have a local address
1676 	 * we handle as though they are non-injected frames.
1677 	 * This code here isn't entirely correct, the local MAC address
1678 	 * isn't always enough to find the interface to use; for proper
1679 	 * VLAN/WDS support we will need a different mechanism (which
1680 	 * likely isn't going to be monitor interfaces).
1681 	 */
1682 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1683 
1684 	list_for_each_entry_rcu(tmp_sdata, &local->interfaces, list) {
1685 		if (!ieee80211_sdata_running(tmp_sdata))
1686 			continue;
1687 		if (tmp_sdata->vif.type == NL80211_IFTYPE_MONITOR ||
1688 		    tmp_sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
1689 		    tmp_sdata->vif.type == NL80211_IFTYPE_WDS)
1690 			continue;
1691 		if (ether_addr_equal(tmp_sdata->vif.addr, hdr->addr2)) {
1692 			sdata = tmp_sdata;
1693 			break;
1694 		}
1695 	}
1696 
1697 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1698 	if (!chanctx_conf) {
1699 		tmp_sdata = rcu_dereference(local->monitor_sdata);
1700 		if (tmp_sdata)
1701 			chanctx_conf =
1702 				rcu_dereference(tmp_sdata->vif.chanctx_conf);
1703 	}
1704 
1705 	if (chanctx_conf)
1706 		chan = chanctx_conf->def.chan;
1707 	else if (!local->use_chanctx)
1708 		chan = local->_oper_channel;
1709 	else
1710 		goto fail_rcu;
1711 
1712 	/*
1713 	 * Frame injection is not allowed if beaconing is not allowed
1714 	 * or if we need radar detection. Beaconing is usually not allowed when
1715 	 * the mode or operation (Adhoc, AP, Mesh) does not support DFS.
1716 	 * Passive scan is also used in world regulatory domains where
1717 	 * your country is not known and as such it should be treated as
1718 	 * NO TX unless the channel is explicitly allowed in which case
1719 	 * your current regulatory domain would not have the passive scan
1720 	 * flag.
1721 	 *
1722 	 * Since AP mode uses monitor interfaces to inject/TX management
1723 	 * frames we can make AP mode the exception to this rule once it
1724 	 * supports radar detection as its implementation can deal with
1725 	 * radar detection by itself. We can do that later by adding a
1726 	 * monitor flag interfaces used for AP support.
1727 	 */
1728 	if ((chan->flags & (IEEE80211_CHAN_NO_IBSS | IEEE80211_CHAN_RADAR |
1729 			    IEEE80211_CHAN_PASSIVE_SCAN)))
1730 		goto fail_rcu;
1731 
1732 	ieee80211_xmit(sdata, skb, chan->band);
1733 	rcu_read_unlock();
1734 
1735 	return NETDEV_TX_OK;
1736 
1737 fail_rcu:
1738 	rcu_read_unlock();
1739 fail:
1740 	dev_kfree_skb(skb);
1741 	return NETDEV_TX_OK; /* meaning, we dealt with the skb */
1742 }
1743 
1744 /**
1745  * ieee80211_subif_start_xmit - netif start_xmit function for Ethernet-type
1746  * subinterfaces (wlan#, WDS, and VLAN interfaces)
1747  * @skb: packet to be sent
1748  * @dev: incoming interface
1749  *
1750  * Returns: 0 on success (and frees skb in this case) or 1 on failure (skb will
1751  * not be freed, and caller is responsible for either retrying later or freeing
1752  * skb).
1753  *
1754  * This function takes in an Ethernet header and encapsulates it with suitable
1755  * IEEE 802.11 header based on which interface the packet is coming in. The
1756  * encapsulated packet will then be passed to master interface, wlan#.11, for
1757  * transmission (through low-level driver).
1758  */
1759 netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb,
1760 				    struct net_device *dev)
1761 {
1762 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1763 	struct ieee80211_local *local = sdata->local;
1764 	struct ieee80211_tx_info *info;
1765 	int head_need;
1766 	u16 ethertype, hdrlen,  meshhdrlen = 0;
1767 	__le16 fc;
1768 	struct ieee80211_hdr hdr;
1769 	struct ieee80211s_hdr mesh_hdr __maybe_unused;
1770 	struct mesh_path __maybe_unused *mppath = NULL, *mpath = NULL;
1771 	const u8 *encaps_data;
1772 	int encaps_len, skip_header_bytes;
1773 	int nh_pos, h_pos;
1774 	struct sta_info *sta = NULL;
1775 	bool wme_sta = false, authorized = false, tdls_auth = false;
1776 	bool tdls_direct = false;
1777 	bool multicast;
1778 	u32 info_flags = 0;
1779 	u16 info_id = 0;
1780 	struct ieee80211_chanctx_conf *chanctx_conf;
1781 	struct ieee80211_sub_if_data *ap_sdata;
1782 	enum ieee80211_band band;
1783 
1784 	if (unlikely(skb->len < ETH_HLEN))
1785 		goto fail;
1786 
1787 	/* convert Ethernet header to proper 802.11 header (based on
1788 	 * operation mode) */
1789 	ethertype = (skb->data[12] << 8) | skb->data[13];
1790 	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_DATA);
1791 
1792 	rcu_read_lock();
1793 
1794 	switch (sdata->vif.type) {
1795 	case NL80211_IFTYPE_AP_VLAN:
1796 		sta = rcu_dereference(sdata->u.vlan.sta);
1797 		if (sta) {
1798 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1799 			/* RA TA DA SA */
1800 			memcpy(hdr.addr1, sta->sta.addr, ETH_ALEN);
1801 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1802 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1803 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1804 			hdrlen = 30;
1805 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
1806 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1807 		}
1808 		ap_sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
1809 					u.ap);
1810 		chanctx_conf = rcu_dereference(ap_sdata->vif.chanctx_conf);
1811 		if (!chanctx_conf)
1812 			goto fail_rcu;
1813 		band = chanctx_conf->def.chan->band;
1814 		if (sta)
1815 			break;
1816 		/* fall through */
1817 	case NL80211_IFTYPE_AP:
1818 		if (sdata->vif.type == NL80211_IFTYPE_AP)
1819 			chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1820 		if (!chanctx_conf)
1821 			goto fail_rcu;
1822 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
1823 		/* DA BSSID SA */
1824 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1825 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1826 		memcpy(hdr.addr3, skb->data + ETH_ALEN, ETH_ALEN);
1827 		hdrlen = 24;
1828 		band = chanctx_conf->def.chan->band;
1829 		break;
1830 	case NL80211_IFTYPE_WDS:
1831 		fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
1832 		/* RA TA DA SA */
1833 		memcpy(hdr.addr1, sdata->u.wds.remote_addr, ETH_ALEN);
1834 		memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1835 		memcpy(hdr.addr3, skb->data, ETH_ALEN);
1836 		memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1837 		hdrlen = 30;
1838 		/*
1839 		 * This is the exception! WDS style interfaces are prohibited
1840 		 * when channel contexts are in used so this must be valid
1841 		 */
1842 		band = local->hw.conf.channel->band;
1843 		break;
1844 #ifdef CONFIG_MAC80211_MESH
1845 	case NL80211_IFTYPE_MESH_POINT:
1846 		if (!sdata->u.mesh.mshcfg.dot11MeshTTL) {
1847 			/* Do not send frames with mesh_ttl == 0 */
1848 			sdata->u.mesh.mshstats.dropped_frames_ttl++;
1849 			goto fail_rcu;
1850 		}
1851 
1852 		if (!is_multicast_ether_addr(skb->data)) {
1853 			struct sta_info *next_hop;
1854 			bool mpp_lookup = true;
1855 
1856 			mpath = mesh_path_lookup(sdata, skb->data);
1857 			if (mpath) {
1858 				mpp_lookup = false;
1859 				next_hop = rcu_dereference(mpath->next_hop);
1860 				if (!next_hop ||
1861 				    !(mpath->flags & (MESH_PATH_ACTIVE |
1862 						      MESH_PATH_RESOLVING)))
1863 					mpp_lookup = true;
1864 			}
1865 
1866 			if (mpp_lookup)
1867 				mppath = mpp_path_lookup(sdata, skb->data);
1868 
1869 			if (mppath && mpath)
1870 				mesh_path_del(mpath->sdata, mpath->dst);
1871 		}
1872 
1873 		/*
1874 		 * Use address extension if it is a packet from
1875 		 * another interface or if we know the destination
1876 		 * is being proxied by a portal (i.e. portal address
1877 		 * differs from proxied address)
1878 		 */
1879 		if (ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN) &&
1880 		    !(mppath && !ether_addr_equal(mppath->mpp, skb->data))) {
1881 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1882 					skb->data, skb->data + ETH_ALEN);
1883 			meshhdrlen = ieee80211_new_mesh_header(sdata, &mesh_hdr,
1884 							       NULL, NULL);
1885 		} else {
1886 			/* DS -> MBSS (802.11-2012 13.11.3.3).
1887 			 * For unicast with unknown forwarding information,
1888 			 * destination might be in the MBSS or if that fails
1889 			 * forwarded to another mesh gate. In either case
1890 			 * resolution will be handled in ieee80211_xmit(), so
1891 			 * leave the original DA. This also works for mcast */
1892 			const u8 *mesh_da = skb->data;
1893 
1894 			if (mppath)
1895 				mesh_da = mppath->mpp;
1896 			else if (mpath)
1897 				mesh_da = mpath->dst;
1898 
1899 			hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
1900 					mesh_da, sdata->vif.addr);
1901 			if (is_multicast_ether_addr(mesh_da))
1902 				/* DA TA mSA AE:SA */
1903 				meshhdrlen = ieee80211_new_mesh_header(
1904 						sdata, &mesh_hdr,
1905 						skb->data + ETH_ALEN, NULL);
1906 			else
1907 				/* RA TA mDA mSA AE:DA SA */
1908 				meshhdrlen = ieee80211_new_mesh_header(
1909 						sdata, &mesh_hdr, skb->data,
1910 						skb->data + ETH_ALEN);
1911 
1912 		}
1913 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1914 		if (!chanctx_conf)
1915 			goto fail_rcu;
1916 		band = chanctx_conf->def.chan->band;
1917 		break;
1918 #endif
1919 	case NL80211_IFTYPE_STATION:
1920 		if (sdata->wdev.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS) {
1921 			bool tdls_peer = false;
1922 
1923 			sta = sta_info_get(sdata, skb->data);
1924 			if (sta) {
1925 				authorized = test_sta_flag(sta,
1926 							WLAN_STA_AUTHORIZED);
1927 				wme_sta = test_sta_flag(sta, WLAN_STA_WME);
1928 				tdls_peer = test_sta_flag(sta,
1929 							 WLAN_STA_TDLS_PEER);
1930 				tdls_auth = test_sta_flag(sta,
1931 						WLAN_STA_TDLS_PEER_AUTH);
1932 			}
1933 
1934 			/*
1935 			 * If the TDLS link is enabled, send everything
1936 			 * directly. Otherwise, allow TDLS setup frames
1937 			 * to be transmitted indirectly.
1938 			 */
1939 			tdls_direct = tdls_peer && (tdls_auth ||
1940 				 !(ethertype == ETH_P_TDLS && skb->len > 14 &&
1941 				   skb->data[14] == WLAN_TDLS_SNAP_RFTYPE));
1942 		}
1943 
1944 		if (tdls_direct) {
1945 			/* link during setup - throw out frames to peer */
1946 			if (!tdls_auth)
1947 				goto fail_rcu;
1948 
1949 			/* DA SA BSSID */
1950 			memcpy(hdr.addr1, skb->data, ETH_ALEN);
1951 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1952 			memcpy(hdr.addr3, sdata->u.mgd.bssid, ETH_ALEN);
1953 			hdrlen = 24;
1954 		}  else if (sdata->u.mgd.use_4addr &&
1955 			    cpu_to_be16(ethertype) != sdata->control_port_protocol) {
1956 			fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS |
1957 					  IEEE80211_FCTL_TODS);
1958 			/* RA TA DA SA */
1959 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1960 			memcpy(hdr.addr2, sdata->vif.addr, ETH_ALEN);
1961 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1962 			memcpy(hdr.addr4, skb->data + ETH_ALEN, ETH_ALEN);
1963 			hdrlen = 30;
1964 		} else {
1965 			fc |= cpu_to_le16(IEEE80211_FCTL_TODS);
1966 			/* BSSID SA DA */
1967 			memcpy(hdr.addr1, sdata->u.mgd.bssid, ETH_ALEN);
1968 			memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1969 			memcpy(hdr.addr3, skb->data, ETH_ALEN);
1970 			hdrlen = 24;
1971 		}
1972 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1973 		if (!chanctx_conf)
1974 			goto fail_rcu;
1975 		band = chanctx_conf->def.chan->band;
1976 		break;
1977 	case NL80211_IFTYPE_ADHOC:
1978 		/* DA SA BSSID */
1979 		memcpy(hdr.addr1, skb->data, ETH_ALEN);
1980 		memcpy(hdr.addr2, skb->data + ETH_ALEN, ETH_ALEN);
1981 		memcpy(hdr.addr3, sdata->u.ibss.bssid, ETH_ALEN);
1982 		hdrlen = 24;
1983 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
1984 		if (!chanctx_conf)
1985 			goto fail_rcu;
1986 		band = chanctx_conf->def.chan->band;
1987 		break;
1988 	default:
1989 		goto fail_rcu;
1990 	}
1991 
1992 	/*
1993 	 * There's no need to try to look up the destination
1994 	 * if it is a multicast address (which can only happen
1995 	 * in AP mode)
1996 	 */
1997 	multicast = is_multicast_ether_addr(hdr.addr1);
1998 	if (!multicast) {
1999 		sta = sta_info_get(sdata, hdr.addr1);
2000 		if (sta) {
2001 			authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
2002 			wme_sta = test_sta_flag(sta, WLAN_STA_WME);
2003 		}
2004 	}
2005 
2006 	/* For mesh, the use of the QoS header is mandatory */
2007 	if (ieee80211_vif_is_mesh(&sdata->vif))
2008 		wme_sta = true;
2009 
2010 	/* receiver and we are QoS enabled, use a QoS type frame */
2011 	if (wme_sta && local->hw.queues >= IEEE80211_NUM_ACS) {
2012 		fc |= cpu_to_le16(IEEE80211_STYPE_QOS_DATA);
2013 		hdrlen += 2;
2014 	}
2015 
2016 	/*
2017 	 * Drop unicast frames to unauthorised stations unless they are
2018 	 * EAPOL frames from the local station.
2019 	 */
2020 	if (unlikely(!ieee80211_vif_is_mesh(&sdata->vif) &&
2021 		     !is_multicast_ether_addr(hdr.addr1) && !authorized &&
2022 		     (cpu_to_be16(ethertype) != sdata->control_port_protocol ||
2023 		      !ether_addr_equal(sdata->vif.addr, skb->data + ETH_ALEN)))) {
2024 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
2025 		net_info_ratelimited("%s: dropped frame to %pM (unauthorized port)\n",
2026 				    dev->name, hdr.addr1);
2027 #endif
2028 
2029 		I802_DEBUG_INC(local->tx_handlers_drop_unauth_port);
2030 
2031 		goto fail_rcu;
2032 	}
2033 
2034 	if (unlikely(!multicast && skb->sk &&
2035 		     skb_shinfo(skb)->tx_flags & SKBTX_WIFI_STATUS)) {
2036 		struct sk_buff *orig_skb = skb;
2037 
2038 		skb = skb_clone(skb, GFP_ATOMIC);
2039 		if (skb) {
2040 			unsigned long flags;
2041 			int id;
2042 
2043 			spin_lock_irqsave(&local->ack_status_lock, flags);
2044 			id = idr_alloc(&local->ack_status_frames, orig_skb,
2045 				       1, 0x10000, GFP_ATOMIC);
2046 			spin_unlock_irqrestore(&local->ack_status_lock, flags);
2047 
2048 			if (id >= 0) {
2049 				info_id = id;
2050 				info_flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
2051 			} else if (skb_shared(skb)) {
2052 				kfree_skb(orig_skb);
2053 			} else {
2054 				kfree_skb(skb);
2055 				skb = orig_skb;
2056 			}
2057 		} else {
2058 			/* couldn't clone -- lose tx status ... */
2059 			skb = orig_skb;
2060 		}
2061 	}
2062 
2063 	/*
2064 	 * If the skb is shared we need to obtain our own copy.
2065 	 */
2066 	if (skb_shared(skb)) {
2067 		struct sk_buff *tmp_skb = skb;
2068 
2069 		/* can't happen -- skb is a clone if info_id != 0 */
2070 		WARN_ON(info_id);
2071 
2072 		skb = skb_clone(skb, GFP_ATOMIC);
2073 		kfree_skb(tmp_skb);
2074 
2075 		if (!skb)
2076 			goto fail_rcu;
2077 	}
2078 
2079 	hdr.frame_control = fc;
2080 	hdr.duration_id = 0;
2081 	hdr.seq_ctrl = 0;
2082 
2083 	skip_header_bytes = ETH_HLEN;
2084 	if (ethertype == ETH_P_AARP || ethertype == ETH_P_IPX) {
2085 		encaps_data = bridge_tunnel_header;
2086 		encaps_len = sizeof(bridge_tunnel_header);
2087 		skip_header_bytes -= 2;
2088 	} else if (ethertype >= 0x600) {
2089 		encaps_data = rfc1042_header;
2090 		encaps_len = sizeof(rfc1042_header);
2091 		skip_header_bytes -= 2;
2092 	} else {
2093 		encaps_data = NULL;
2094 		encaps_len = 0;
2095 	}
2096 
2097 	nh_pos = skb_network_header(skb) - skb->data;
2098 	h_pos = skb_transport_header(skb) - skb->data;
2099 
2100 	skb_pull(skb, skip_header_bytes);
2101 	nh_pos -= skip_header_bytes;
2102 	h_pos -= skip_header_bytes;
2103 
2104 	head_need = hdrlen + encaps_len + meshhdrlen - skb_headroom(skb);
2105 
2106 	/*
2107 	 * So we need to modify the skb header and hence need a copy of
2108 	 * that. The head_need variable above doesn't, so far, include
2109 	 * the needed header space that we don't need right away. If we
2110 	 * can, then we don't reallocate right now but only after the
2111 	 * frame arrives at the master device (if it does...)
2112 	 *
2113 	 * If we cannot, however, then we will reallocate to include all
2114 	 * the ever needed space. Also, if we need to reallocate it anyway,
2115 	 * make it big enough for everything we may ever need.
2116 	 */
2117 
2118 	if (head_need > 0 || skb_cloned(skb)) {
2119 		head_need += IEEE80211_ENCRYPT_HEADROOM;
2120 		head_need += local->tx_headroom;
2121 		head_need = max_t(int, 0, head_need);
2122 		if (ieee80211_skb_resize(sdata, skb, head_need, true)) {
2123 			ieee80211_free_txskb(&local->hw, skb);
2124 			skb = NULL;
2125 			goto fail_rcu;
2126 		}
2127 	}
2128 
2129 	if (encaps_data) {
2130 		memcpy(skb_push(skb, encaps_len), encaps_data, encaps_len);
2131 		nh_pos += encaps_len;
2132 		h_pos += encaps_len;
2133 	}
2134 
2135 #ifdef CONFIG_MAC80211_MESH
2136 	if (meshhdrlen > 0) {
2137 		memcpy(skb_push(skb, meshhdrlen), &mesh_hdr, meshhdrlen);
2138 		nh_pos += meshhdrlen;
2139 		h_pos += meshhdrlen;
2140 	}
2141 #endif
2142 
2143 	if (ieee80211_is_data_qos(fc)) {
2144 		__le16 *qos_control;
2145 
2146 		qos_control = (__le16*) skb_push(skb, 2);
2147 		memcpy(skb_push(skb, hdrlen - 2), &hdr, hdrlen - 2);
2148 		/*
2149 		 * Maybe we could actually set some fields here, for now just
2150 		 * initialise to zero to indicate no special operation.
2151 		 */
2152 		*qos_control = 0;
2153 	} else
2154 		memcpy(skb_push(skb, hdrlen), &hdr, hdrlen);
2155 
2156 	nh_pos += hdrlen;
2157 	h_pos += hdrlen;
2158 
2159 	dev->stats.tx_packets++;
2160 	dev->stats.tx_bytes += skb->len;
2161 
2162 	/* Update skb pointers to various headers since this modified frame
2163 	 * is going to go through Linux networking code that may potentially
2164 	 * need things like pointer to IP header. */
2165 	skb_set_mac_header(skb, 0);
2166 	skb_set_network_header(skb, nh_pos);
2167 	skb_set_transport_header(skb, h_pos);
2168 
2169 	info = IEEE80211_SKB_CB(skb);
2170 	memset(info, 0, sizeof(*info));
2171 
2172 	dev->trans_start = jiffies;
2173 
2174 	info->flags = info_flags;
2175 	info->ack_frame_id = info_id;
2176 
2177 	ieee80211_xmit(sdata, skb, band);
2178 	rcu_read_unlock();
2179 
2180 	return NETDEV_TX_OK;
2181 
2182  fail_rcu:
2183 	rcu_read_unlock();
2184  fail:
2185 	dev_kfree_skb(skb);
2186 	return NETDEV_TX_OK;
2187 }
2188 
2189 
2190 /*
2191  * ieee80211_clear_tx_pending may not be called in a context where
2192  * it is possible that it packets could come in again.
2193  */
2194 void ieee80211_clear_tx_pending(struct ieee80211_local *local)
2195 {
2196 	struct sk_buff *skb;
2197 	int i;
2198 
2199 	for (i = 0; i < local->hw.queues; i++) {
2200 		while ((skb = skb_dequeue(&local->pending[i])) != NULL)
2201 			ieee80211_free_txskb(&local->hw, skb);
2202 	}
2203 }
2204 
2205 /*
2206  * Returns false if the frame couldn't be transmitted but was queued instead,
2207  * which in this case means re-queued -- take as an indication to stop sending
2208  * more pending frames.
2209  */
2210 static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
2211 				     struct sk_buff *skb)
2212 {
2213 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2214 	struct ieee80211_sub_if_data *sdata;
2215 	struct sta_info *sta;
2216 	struct ieee80211_hdr *hdr;
2217 	bool result;
2218 	struct ieee80211_chanctx_conf *chanctx_conf;
2219 
2220 	sdata = vif_to_sdata(info->control.vif);
2221 
2222 	if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
2223 		chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2224 		if (unlikely(!chanctx_conf)) {
2225 			dev_kfree_skb(skb);
2226 			return true;
2227 		}
2228 		result = ieee80211_tx(sdata, skb, true,
2229 				      chanctx_conf->def.chan->band);
2230 	} else {
2231 		struct sk_buff_head skbs;
2232 
2233 		__skb_queue_head_init(&skbs);
2234 		__skb_queue_tail(&skbs, skb);
2235 
2236 		hdr = (struct ieee80211_hdr *)skb->data;
2237 		sta = sta_info_get(sdata, hdr->addr1);
2238 
2239 		result = __ieee80211_tx(local, &skbs, skb->len, sta, true);
2240 	}
2241 
2242 	return result;
2243 }
2244 
2245 /*
2246  * Transmit all pending packets. Called from tasklet.
2247  */
2248 void ieee80211_tx_pending(unsigned long data)
2249 {
2250 	struct ieee80211_local *local = (struct ieee80211_local *)data;
2251 	unsigned long flags;
2252 	int i;
2253 	bool txok;
2254 
2255 	rcu_read_lock();
2256 
2257 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
2258 	for (i = 0; i < local->hw.queues; i++) {
2259 		/*
2260 		 * If queue is stopped by something other than due to pending
2261 		 * frames, or we have no pending frames, proceed to next queue.
2262 		 */
2263 		if (local->queue_stop_reasons[i] ||
2264 		    skb_queue_empty(&local->pending[i]))
2265 			continue;
2266 
2267 		while (!skb_queue_empty(&local->pending[i])) {
2268 			struct sk_buff *skb = __skb_dequeue(&local->pending[i]);
2269 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2270 
2271 			if (WARN_ON(!info->control.vif)) {
2272 				ieee80211_free_txskb(&local->hw, skb);
2273 				continue;
2274 			}
2275 
2276 			spin_unlock_irqrestore(&local->queue_stop_reason_lock,
2277 						flags);
2278 
2279 			txok = ieee80211_tx_pending_skb(local, skb);
2280 			spin_lock_irqsave(&local->queue_stop_reason_lock,
2281 					  flags);
2282 			if (!txok)
2283 				break;
2284 		}
2285 
2286 		if (skb_queue_empty(&local->pending[i]))
2287 			ieee80211_propagate_queue_wake(local, i);
2288 	}
2289 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
2290 
2291 	rcu_read_unlock();
2292 }
2293 
2294 /* functions for drivers to get certain frames */
2295 
2296 static void __ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2297 				       struct ps_data *ps, struct sk_buff *skb)
2298 {
2299 	u8 *pos, *tim;
2300 	int aid0 = 0;
2301 	int i, have_bits = 0, n1, n2;
2302 
2303 	/* Generate bitmap for TIM only if there are any STAs in power save
2304 	 * mode. */
2305 	if (atomic_read(&ps->num_sta_ps) > 0)
2306 		/* in the hope that this is faster than
2307 		 * checking byte-for-byte */
2308 		have_bits = !bitmap_empty((unsigned long*)ps->tim,
2309 					  IEEE80211_MAX_AID+1);
2310 
2311 	if (ps->dtim_count == 0)
2312 		ps->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
2313 	else
2314 		ps->dtim_count--;
2315 
2316 	tim = pos = (u8 *) skb_put(skb, 6);
2317 	*pos++ = WLAN_EID_TIM;
2318 	*pos++ = 4;
2319 	*pos++ = ps->dtim_count;
2320 	*pos++ = sdata->vif.bss_conf.dtim_period;
2321 
2322 	if (ps->dtim_count == 0 && !skb_queue_empty(&ps->bc_buf))
2323 		aid0 = 1;
2324 
2325 	ps->dtim_bc_mc = aid0 == 1;
2326 
2327 	if (have_bits) {
2328 		/* Find largest even number N1 so that bits numbered 1 through
2329 		 * (N1 x 8) - 1 in the bitmap are 0 and number N2 so that bits
2330 		 * (N2 + 1) x 8 through 2007 are 0. */
2331 		n1 = 0;
2332 		for (i = 0; i < IEEE80211_MAX_TIM_LEN; i++) {
2333 			if (ps->tim[i]) {
2334 				n1 = i & 0xfe;
2335 				break;
2336 			}
2337 		}
2338 		n2 = n1;
2339 		for (i = IEEE80211_MAX_TIM_LEN - 1; i >= n1; i--) {
2340 			if (ps->tim[i]) {
2341 				n2 = i;
2342 				break;
2343 			}
2344 		}
2345 
2346 		/* Bitmap control */
2347 		*pos++ = n1 | aid0;
2348 		/* Part Virt Bitmap */
2349 		skb_put(skb, n2 - n1);
2350 		memcpy(pos, ps->tim + n1, n2 - n1 + 1);
2351 
2352 		tim[1] = n2 - n1 + 4;
2353 	} else {
2354 		*pos++ = aid0; /* Bitmap control */
2355 		*pos++ = 0; /* Part Virt Bitmap */
2356 	}
2357 }
2358 
2359 static int ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
2360 				    struct ps_data *ps, struct sk_buff *skb)
2361 {
2362 	struct ieee80211_local *local = sdata->local;
2363 
2364 	/*
2365 	 * Not very nice, but we want to allow the driver to call
2366 	 * ieee80211_beacon_get() as a response to the set_tim()
2367 	 * callback. That, however, is already invoked under the
2368 	 * sta_lock to guarantee consistent and race-free update
2369 	 * of the tim bitmap in mac80211 and the driver.
2370 	 */
2371 	if (local->tim_in_locked_section) {
2372 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2373 	} else {
2374 		spin_lock_bh(&local->tim_lock);
2375 		__ieee80211_beacon_add_tim(sdata, ps, skb);
2376 		spin_unlock_bh(&local->tim_lock);
2377 	}
2378 
2379 	return 0;
2380 }
2381 
2382 struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
2383 					 struct ieee80211_vif *vif,
2384 					 u16 *tim_offset, u16 *tim_length)
2385 {
2386 	struct ieee80211_local *local = hw_to_local(hw);
2387 	struct sk_buff *skb = NULL;
2388 	struct ieee80211_tx_info *info;
2389 	struct ieee80211_sub_if_data *sdata = NULL;
2390 	enum ieee80211_band band;
2391 	struct ieee80211_tx_rate_control txrc;
2392 	struct ieee80211_chanctx_conf *chanctx_conf;
2393 
2394 	rcu_read_lock();
2395 
2396 	sdata = vif_to_sdata(vif);
2397 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2398 
2399 	if (!ieee80211_sdata_running(sdata) || !chanctx_conf)
2400 		goto out;
2401 
2402 	if (tim_offset)
2403 		*tim_offset = 0;
2404 	if (tim_length)
2405 		*tim_length = 0;
2406 
2407 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2408 		struct ieee80211_if_ap *ap = &sdata->u.ap;
2409 		struct beacon_data *beacon = rcu_dereference(ap->beacon);
2410 
2411 		if (beacon) {
2412 			/*
2413 			 * headroom, head length,
2414 			 * tail length and maximum TIM length
2415 			 */
2416 			skb = dev_alloc_skb(local->tx_headroom +
2417 					    beacon->head_len +
2418 					    beacon->tail_len + 256);
2419 			if (!skb)
2420 				goto out;
2421 
2422 			skb_reserve(skb, local->tx_headroom);
2423 			memcpy(skb_put(skb, beacon->head_len), beacon->head,
2424 			       beacon->head_len);
2425 
2426 			ieee80211_beacon_add_tim(sdata, &ap->ps, skb);
2427 
2428 			if (tim_offset)
2429 				*tim_offset = beacon->head_len;
2430 			if (tim_length)
2431 				*tim_length = skb->len - beacon->head_len;
2432 
2433 			if (beacon->tail)
2434 				memcpy(skb_put(skb, beacon->tail_len),
2435 				       beacon->tail, beacon->tail_len);
2436 		} else
2437 			goto out;
2438 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
2439 		struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
2440 		struct ieee80211_hdr *hdr;
2441 		struct sk_buff *presp = rcu_dereference(ifibss->presp);
2442 
2443 		if (!presp)
2444 			goto out;
2445 
2446 		skb = skb_copy(presp, GFP_ATOMIC);
2447 		if (!skb)
2448 			goto out;
2449 
2450 		hdr = (struct ieee80211_hdr *) skb->data;
2451 		hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2452 						 IEEE80211_STYPE_BEACON);
2453 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2454 		struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
2455 		struct beacon_data *bcn = rcu_dereference(ifmsh->beacon);
2456 
2457 		if (!bcn)
2458 			goto out;
2459 
2460 		if (ifmsh->sync_ops)
2461 			ifmsh->sync_ops->adjust_tbtt(
2462 						sdata);
2463 
2464 		skb = dev_alloc_skb(local->tx_headroom +
2465 				    bcn->head_len +
2466 				    256 + /* TIM IE */
2467 				    bcn->tail_len);
2468 		if (!skb)
2469 			goto out;
2470 		skb_reserve(skb, local->tx_headroom);
2471 		memcpy(skb_put(skb, bcn->head_len), bcn->head, bcn->head_len);
2472 		ieee80211_beacon_add_tim(sdata, &ifmsh->ps, skb);
2473 		memcpy(skb_put(skb, bcn->tail_len), bcn->tail, bcn->tail_len);
2474 	} else {
2475 		WARN_ON(1);
2476 		goto out;
2477 	}
2478 
2479 	band = chanctx_conf->def.chan->band;
2480 
2481 	info = IEEE80211_SKB_CB(skb);
2482 
2483 	info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
2484 	info->flags |= IEEE80211_TX_CTL_NO_ACK;
2485 	info->band = band;
2486 
2487 	memset(&txrc, 0, sizeof(txrc));
2488 	txrc.hw = hw;
2489 	txrc.sband = local->hw.wiphy->bands[band];
2490 	txrc.bss_conf = &sdata->vif.bss_conf;
2491 	txrc.skb = skb;
2492 	txrc.reported_rate.idx = -1;
2493 	txrc.rate_idx_mask = sdata->rc_rateidx_mask[band];
2494 	if (txrc.rate_idx_mask == (1 << txrc.sband->n_bitrates) - 1)
2495 		txrc.max_rate_idx = -1;
2496 	else
2497 		txrc.max_rate_idx = fls(txrc.rate_idx_mask) - 1;
2498 	memcpy(txrc.rate_idx_mcs_mask, sdata->rc_rateidx_mcs_mask[band],
2499 	       sizeof(txrc.rate_idx_mcs_mask));
2500 	txrc.bss = true;
2501 	rate_control_get_rate(sdata, NULL, &txrc);
2502 
2503 	info->control.vif = vif;
2504 
2505 	info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT |
2506 			IEEE80211_TX_CTL_ASSIGN_SEQ |
2507 			IEEE80211_TX_CTL_FIRST_FRAGMENT;
2508  out:
2509 	rcu_read_unlock();
2510 	return skb;
2511 }
2512 EXPORT_SYMBOL(ieee80211_beacon_get_tim);
2513 
2514 struct sk_buff *ieee80211_proberesp_get(struct ieee80211_hw *hw,
2515 					struct ieee80211_vif *vif)
2516 {
2517 	struct ieee80211_if_ap *ap = NULL;
2518 	struct sk_buff *skb = NULL;
2519 	struct probe_resp *presp = NULL;
2520 	struct ieee80211_hdr *hdr;
2521 	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
2522 
2523 	if (sdata->vif.type != NL80211_IFTYPE_AP)
2524 		return NULL;
2525 
2526 	rcu_read_lock();
2527 
2528 	ap = &sdata->u.ap;
2529 	presp = rcu_dereference(ap->probe_resp);
2530 	if (!presp)
2531 		goto out;
2532 
2533 	skb = dev_alloc_skb(presp->len);
2534 	if (!skb)
2535 		goto out;
2536 
2537 	memcpy(skb_put(skb, presp->len), presp->data, presp->len);
2538 
2539 	hdr = (struct ieee80211_hdr *) skb->data;
2540 	memset(hdr->addr1, 0, sizeof(hdr->addr1));
2541 
2542 out:
2543 	rcu_read_unlock();
2544 	return skb;
2545 }
2546 EXPORT_SYMBOL(ieee80211_proberesp_get);
2547 
2548 struct sk_buff *ieee80211_pspoll_get(struct ieee80211_hw *hw,
2549 				     struct ieee80211_vif *vif)
2550 {
2551 	struct ieee80211_sub_if_data *sdata;
2552 	struct ieee80211_if_managed *ifmgd;
2553 	struct ieee80211_pspoll *pspoll;
2554 	struct ieee80211_local *local;
2555 	struct sk_buff *skb;
2556 
2557 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2558 		return NULL;
2559 
2560 	sdata = vif_to_sdata(vif);
2561 	ifmgd = &sdata->u.mgd;
2562 	local = sdata->local;
2563 
2564 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*pspoll));
2565 	if (!skb)
2566 		return NULL;
2567 
2568 	skb_reserve(skb, local->hw.extra_tx_headroom);
2569 
2570 	pspoll = (struct ieee80211_pspoll *) skb_put(skb, sizeof(*pspoll));
2571 	memset(pspoll, 0, sizeof(*pspoll));
2572 	pspoll->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
2573 					    IEEE80211_STYPE_PSPOLL);
2574 	pspoll->aid = cpu_to_le16(ifmgd->aid);
2575 
2576 	/* aid in PS-Poll has its two MSBs each set to 1 */
2577 	pspoll->aid |= cpu_to_le16(1 << 15 | 1 << 14);
2578 
2579 	memcpy(pspoll->bssid, ifmgd->bssid, ETH_ALEN);
2580 	memcpy(pspoll->ta, vif->addr, ETH_ALEN);
2581 
2582 	return skb;
2583 }
2584 EXPORT_SYMBOL(ieee80211_pspoll_get);
2585 
2586 struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
2587 				       struct ieee80211_vif *vif)
2588 {
2589 	struct ieee80211_hdr_3addr *nullfunc;
2590 	struct ieee80211_sub_if_data *sdata;
2591 	struct ieee80211_if_managed *ifmgd;
2592 	struct ieee80211_local *local;
2593 	struct sk_buff *skb;
2594 
2595 	if (WARN_ON(vif->type != NL80211_IFTYPE_STATION))
2596 		return NULL;
2597 
2598 	sdata = vif_to_sdata(vif);
2599 	ifmgd = &sdata->u.mgd;
2600 	local = sdata->local;
2601 
2602 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*nullfunc));
2603 	if (!skb)
2604 		return NULL;
2605 
2606 	skb_reserve(skb, local->hw.extra_tx_headroom);
2607 
2608 	nullfunc = (struct ieee80211_hdr_3addr *) skb_put(skb,
2609 							  sizeof(*nullfunc));
2610 	memset(nullfunc, 0, sizeof(*nullfunc));
2611 	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
2612 					      IEEE80211_STYPE_NULLFUNC |
2613 					      IEEE80211_FCTL_TODS);
2614 	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
2615 	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
2616 	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);
2617 
2618 	return skb;
2619 }
2620 EXPORT_SYMBOL(ieee80211_nullfunc_get);
2621 
2622 struct sk_buff *ieee80211_probereq_get(struct ieee80211_hw *hw,
2623 				       struct ieee80211_vif *vif,
2624 				       const u8 *ssid, size_t ssid_len,
2625 				       size_t tailroom)
2626 {
2627 	struct ieee80211_sub_if_data *sdata;
2628 	struct ieee80211_local *local;
2629 	struct ieee80211_hdr_3addr *hdr;
2630 	struct sk_buff *skb;
2631 	size_t ie_ssid_len;
2632 	u8 *pos;
2633 
2634 	sdata = vif_to_sdata(vif);
2635 	local = sdata->local;
2636 	ie_ssid_len = 2 + ssid_len;
2637 
2638 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + sizeof(*hdr) +
2639 			    ie_ssid_len + tailroom);
2640 	if (!skb)
2641 		return NULL;
2642 
2643 	skb_reserve(skb, local->hw.extra_tx_headroom);
2644 
2645 	hdr = (struct ieee80211_hdr_3addr *) skb_put(skb, sizeof(*hdr));
2646 	memset(hdr, 0, sizeof(*hdr));
2647 	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
2648 					 IEEE80211_STYPE_PROBE_REQ);
2649 	eth_broadcast_addr(hdr->addr1);
2650 	memcpy(hdr->addr2, vif->addr, ETH_ALEN);
2651 	eth_broadcast_addr(hdr->addr3);
2652 
2653 	pos = skb_put(skb, ie_ssid_len);
2654 	*pos++ = WLAN_EID_SSID;
2655 	*pos++ = ssid_len;
2656 	if (ssid_len)
2657 		memcpy(pos, ssid, ssid_len);
2658 	pos += ssid_len;
2659 
2660 	return skb;
2661 }
2662 EXPORT_SYMBOL(ieee80211_probereq_get);
2663 
2664 void ieee80211_rts_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2665 		       const void *frame, size_t frame_len,
2666 		       const struct ieee80211_tx_info *frame_txctl,
2667 		       struct ieee80211_rts *rts)
2668 {
2669 	const struct ieee80211_hdr *hdr = frame;
2670 
2671 	rts->frame_control =
2672 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_RTS);
2673 	rts->duration = ieee80211_rts_duration(hw, vif, frame_len,
2674 					       frame_txctl);
2675 	memcpy(rts->ra, hdr->addr1, sizeof(rts->ra));
2676 	memcpy(rts->ta, hdr->addr2, sizeof(rts->ta));
2677 }
2678 EXPORT_SYMBOL(ieee80211_rts_get);
2679 
2680 void ieee80211_ctstoself_get(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2681 			     const void *frame, size_t frame_len,
2682 			     const struct ieee80211_tx_info *frame_txctl,
2683 			     struct ieee80211_cts *cts)
2684 {
2685 	const struct ieee80211_hdr *hdr = frame;
2686 
2687 	cts->frame_control =
2688 	    cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_CTS);
2689 	cts->duration = ieee80211_ctstoself_duration(hw, vif,
2690 						     frame_len, frame_txctl);
2691 	memcpy(cts->ra, hdr->addr1, sizeof(cts->ra));
2692 }
2693 EXPORT_SYMBOL(ieee80211_ctstoself_get);
2694 
2695 struct sk_buff *
2696 ieee80211_get_buffered_bc(struct ieee80211_hw *hw,
2697 			  struct ieee80211_vif *vif)
2698 {
2699 	struct ieee80211_local *local = hw_to_local(hw);
2700 	struct sk_buff *skb = NULL;
2701 	struct ieee80211_tx_data tx;
2702 	struct ieee80211_sub_if_data *sdata;
2703 	struct ps_data *ps;
2704 	struct ieee80211_tx_info *info;
2705 	struct ieee80211_chanctx_conf *chanctx_conf;
2706 
2707 	sdata = vif_to_sdata(vif);
2708 
2709 	rcu_read_lock();
2710 	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
2711 
2712 	if (!chanctx_conf)
2713 		goto out;
2714 
2715 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
2716 		struct beacon_data *beacon =
2717 				rcu_dereference(sdata->u.ap.beacon);
2718 
2719 		if (!beacon || !beacon->head)
2720 			goto out;
2721 
2722 		ps = &sdata->u.ap.ps;
2723 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
2724 		ps = &sdata->u.mesh.ps;
2725 	} else {
2726 		goto out;
2727 	}
2728 
2729 	if (ps->dtim_count != 0 || !ps->dtim_bc_mc)
2730 		goto out; /* send buffered bc/mc only after DTIM beacon */
2731 
2732 	while (1) {
2733 		skb = skb_dequeue(&ps->bc_buf);
2734 		if (!skb)
2735 			goto out;
2736 		local->total_ps_buffered--;
2737 
2738 		if (!skb_queue_empty(&ps->bc_buf) && skb->len >= 2) {
2739 			struct ieee80211_hdr *hdr =
2740 				(struct ieee80211_hdr *) skb->data;
2741 			/* more buffered multicast/broadcast frames ==> set
2742 			 * MoreData flag in IEEE 802.11 header to inform PS
2743 			 * STAs */
2744 			hdr->frame_control |=
2745 				cpu_to_le16(IEEE80211_FCTL_MOREDATA);
2746 		}
2747 
2748 		if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
2749 			sdata = IEEE80211_DEV_TO_SUB_IF(skb->dev);
2750 		if (!ieee80211_tx_prepare(sdata, &tx, skb))
2751 			break;
2752 		dev_kfree_skb_any(skb);
2753 	}
2754 
2755 	info = IEEE80211_SKB_CB(skb);
2756 
2757 	tx.flags |= IEEE80211_TX_PS_BUFFERED;
2758 	info->band = chanctx_conf->def.chan->band;
2759 
2760 	if (invoke_tx_handlers(&tx))
2761 		skb = NULL;
2762  out:
2763 	rcu_read_unlock();
2764 
2765 	return skb;
2766 }
2767 EXPORT_SYMBOL(ieee80211_get_buffered_bc);
2768 
2769 void __ieee80211_tx_skb_tid_band(struct ieee80211_sub_if_data *sdata,
2770 				 struct sk_buff *skb, int tid,
2771 				 enum ieee80211_band band)
2772 {
2773 	int ac = ieee802_1d_to_ac[tid & 7];
2774 
2775 	skb_set_mac_header(skb, 0);
2776 	skb_set_network_header(skb, 0);
2777 	skb_set_transport_header(skb, 0);
2778 
2779 	skb_set_queue_mapping(skb, ac);
2780 	skb->priority = tid;
2781 
2782 	skb->dev = sdata->dev;
2783 
2784 	/*
2785 	 * The other path calling ieee80211_xmit is from the tasklet,
2786 	 * and while we can handle concurrent transmissions locking
2787 	 * requirements are that we do not come into tx with bhs on.
2788 	 */
2789 	local_bh_disable();
2790 	ieee80211_xmit(sdata, skb, band);
2791 	local_bh_enable();
2792 }
2793