xref: /linux/net/mac80211/sta_info.c (revision 1a2ac6d7ecdcde74a4e16f31de64124160fc7237)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2002-2005, Instant802 Networks, Inc.
4  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
5  * Copyright 2013-2014  Intel Mobile Communications GmbH
6  * Copyright (C) 2015 - 2017 Intel Deutschland GmbH
7  * Copyright (C) 2018-2022 Intel Corporation
8  */
9 
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/etherdevice.h>
13 #include <linux/netdevice.h>
14 #include <linux/types.h>
15 #include <linux/slab.h>
16 #include <linux/skbuff.h>
17 #include <linux/if_arp.h>
18 #include <linux/timer.h>
19 #include <linux/rtnetlink.h>
20 
21 #include <net/codel.h>
22 #include <net/mac80211.h>
23 #include "ieee80211_i.h"
24 #include "driver-ops.h"
25 #include "rate.h"
26 #include "sta_info.h"
27 #include "debugfs_sta.h"
28 #include "mesh.h"
29 #include "wme.h"
30 
31 /**
32  * DOC: STA information lifetime rules
33  *
34  * STA info structures (&struct sta_info) are managed in a hash table
35  * for faster lookup and a list for iteration. They are managed using
36  * RCU, i.e. access to the list and hash table is protected by RCU.
37  *
38  * Upon allocating a STA info structure with sta_info_alloc(), the caller
39  * owns that structure. It must then insert it into the hash table using
40  * either sta_info_insert() or sta_info_insert_rcu(); only in the latter
41  * case (which acquires an rcu read section but must not be called from
42  * within one) will the pointer still be valid after the call. Note that
43  * the caller may not do much with the STA info before inserting it, in
44  * particular, it may not start any mesh peer link management or add
45  * encryption keys.
46  *
47  * When the insertion fails (sta_info_insert()) returns non-zero), the
48  * structure will have been freed by sta_info_insert()!
49  *
50  * Station entries are added by mac80211 when you establish a link with a
51  * peer. This means different things for the different type of interfaces
52  * we support. For a regular station this mean we add the AP sta when we
53  * receive an association response from the AP. For IBSS this occurs when
54  * get to know about a peer on the same IBSS. For WDS we add the sta for
55  * the peer immediately upon device open. When using AP mode we add stations
56  * for each respective station upon request from userspace through nl80211.
57  *
58  * In order to remove a STA info structure, various sta_info_destroy_*()
59  * calls are available.
60  *
61  * There is no concept of ownership on a STA entry, each structure is
62  * owned by the global hash table/list until it is removed. All users of
63  * the structure need to be RCU protected so that the structure won't be
64  * freed before they are done using it.
65  */
66 
67 struct sta_link_alloc {
68 	struct link_sta_info info;
69 	struct ieee80211_link_sta sta;
70 	struct rcu_head rcu_head;
71 };
72 
73 static const struct rhashtable_params sta_rht_params = {
74 	.nelem_hint = 3, /* start small */
75 	.automatic_shrinking = true,
76 	.head_offset = offsetof(struct sta_info, hash_node),
77 	.key_offset = offsetof(struct sta_info, addr),
78 	.key_len = ETH_ALEN,
79 	.max_size = CONFIG_MAC80211_STA_HASH_MAX_SIZE,
80 };
81 
82 static const struct rhashtable_params link_sta_rht_params = {
83 	.nelem_hint = 3, /* start small */
84 	.automatic_shrinking = true,
85 	.head_offset = offsetof(struct link_sta_info, link_hash_node),
86 	.key_offset = offsetof(struct link_sta_info, addr),
87 	.key_len = ETH_ALEN,
88 	.max_size = CONFIG_MAC80211_STA_HASH_MAX_SIZE,
89 };
90 
91 /* Caller must hold local->sta_mtx */
92 static int sta_info_hash_del(struct ieee80211_local *local,
93 			     struct sta_info *sta)
94 {
95 	return rhltable_remove(&local->sta_hash, &sta->hash_node,
96 			       sta_rht_params);
97 }
98 
99 static int link_sta_info_hash_add(struct ieee80211_local *local,
100 				  struct link_sta_info *link_sta)
101 {
102 	lockdep_assert_held(&local->sta_mtx);
103 	return rhltable_insert(&local->link_sta_hash,
104 			       &link_sta->link_hash_node,
105 			       link_sta_rht_params);
106 }
107 
108 static int link_sta_info_hash_del(struct ieee80211_local *local,
109 				  struct link_sta_info *link_sta)
110 {
111 	lockdep_assert_held(&local->sta_mtx);
112 	return rhltable_remove(&local->link_sta_hash,
113 			       &link_sta->link_hash_node,
114 			       link_sta_rht_params);
115 }
116 
117 static void __cleanup_single_sta(struct sta_info *sta)
118 {
119 	int ac, i;
120 	struct tid_ampdu_tx *tid_tx;
121 	struct ieee80211_sub_if_data *sdata = sta->sdata;
122 	struct ieee80211_local *local = sdata->local;
123 	struct ps_data *ps;
124 
125 	if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
126 	    test_sta_flag(sta, WLAN_STA_PS_DRIVER) ||
127 	    test_sta_flag(sta, WLAN_STA_PS_DELIVER)) {
128 		if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
129 		    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
130 			ps = &sdata->bss->ps;
131 		else if (ieee80211_vif_is_mesh(&sdata->vif))
132 			ps = &sdata->u.mesh.ps;
133 		else
134 			return;
135 
136 		clear_sta_flag(sta, WLAN_STA_PS_STA);
137 		clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
138 		clear_sta_flag(sta, WLAN_STA_PS_DELIVER);
139 
140 		atomic_dec(&ps->num_sta_ps);
141 	}
142 
143 	for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) {
144 		struct txq_info *txqi;
145 
146 		if (!sta->sta.txq[i])
147 			continue;
148 
149 		txqi = to_txq_info(sta->sta.txq[i]);
150 
151 		ieee80211_txq_purge(local, txqi);
152 	}
153 
154 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
155 		local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]);
156 		ieee80211_purge_tx_queue(&local->hw, &sta->ps_tx_buf[ac]);
157 		ieee80211_purge_tx_queue(&local->hw, &sta->tx_filtered[ac]);
158 	}
159 
160 	if (ieee80211_vif_is_mesh(&sdata->vif))
161 		mesh_sta_cleanup(sta);
162 
163 	cancel_work_sync(&sta->drv_deliver_wk);
164 
165 	/*
166 	 * Destroy aggregation state here. It would be nice to wait for the
167 	 * driver to finish aggregation stop and then clean up, but for now
168 	 * drivers have to handle aggregation stop being requested, followed
169 	 * directly by station destruction.
170 	 */
171 	for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
172 		kfree(sta->ampdu_mlme.tid_start_tx[i]);
173 		tid_tx = rcu_dereference_raw(sta->ampdu_mlme.tid_tx[i]);
174 		if (!tid_tx)
175 			continue;
176 		ieee80211_purge_tx_queue(&local->hw, &tid_tx->pending);
177 		kfree(tid_tx);
178 	}
179 }
180 
181 static void cleanup_single_sta(struct sta_info *sta)
182 {
183 	struct ieee80211_sub_if_data *sdata = sta->sdata;
184 	struct ieee80211_local *local = sdata->local;
185 
186 	__cleanup_single_sta(sta);
187 	sta_info_free(local, sta);
188 }
189 
190 struct rhlist_head *sta_info_hash_lookup(struct ieee80211_local *local,
191 					 const u8 *addr)
192 {
193 	return rhltable_lookup(&local->sta_hash, addr, sta_rht_params);
194 }
195 
196 /* protected by RCU */
197 struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
198 			      const u8 *addr)
199 {
200 	struct ieee80211_local *local = sdata->local;
201 	struct rhlist_head *tmp;
202 	struct sta_info *sta;
203 
204 	rcu_read_lock();
205 	for_each_sta_info(local, addr, sta, tmp) {
206 		if (sta->sdata == sdata) {
207 			rcu_read_unlock();
208 			/* this is safe as the caller must already hold
209 			 * another rcu read section or the mutex
210 			 */
211 			return sta;
212 		}
213 	}
214 	rcu_read_unlock();
215 	return NULL;
216 }
217 
218 /*
219  * Get sta info either from the specified interface
220  * or from one of its vlans
221  */
222 struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
223 				  const u8 *addr)
224 {
225 	struct ieee80211_local *local = sdata->local;
226 	struct rhlist_head *tmp;
227 	struct sta_info *sta;
228 
229 	rcu_read_lock();
230 	for_each_sta_info(local, addr, sta, tmp) {
231 		if (sta->sdata == sdata ||
232 		    (sta->sdata->bss && sta->sdata->bss == sdata->bss)) {
233 			rcu_read_unlock();
234 			/* this is safe as the caller must already hold
235 			 * another rcu read section or the mutex
236 			 */
237 			return sta;
238 		}
239 	}
240 	rcu_read_unlock();
241 	return NULL;
242 }
243 
244 struct rhlist_head *link_sta_info_hash_lookup(struct ieee80211_local *local,
245 					      const u8 *addr)
246 {
247 	return rhltable_lookup(&local->link_sta_hash, addr,
248 			       link_sta_rht_params);
249 }
250 
251 struct link_sta_info *
252 link_sta_info_get_bss(struct ieee80211_sub_if_data *sdata, const u8 *addr)
253 {
254 	struct ieee80211_local *local = sdata->local;
255 	struct rhlist_head *tmp;
256 	struct link_sta_info *link_sta;
257 
258 	rcu_read_lock();
259 	for_each_link_sta_info(local, addr, link_sta, tmp) {
260 		struct sta_info *sta = link_sta->sta;
261 
262 		if (sta->sdata == sdata ||
263 		    (sta->sdata->bss && sta->sdata->bss == sdata->bss)) {
264 			rcu_read_unlock();
265 			/* this is safe as the caller must already hold
266 			 * another rcu read section or the mutex
267 			 */
268 			return link_sta;
269 		}
270 	}
271 	rcu_read_unlock();
272 	return NULL;
273 }
274 
275 struct ieee80211_sta *
276 ieee80211_find_sta_by_link_addrs(struct ieee80211_hw *hw,
277 				 const u8 *addr,
278 				 const u8 *localaddr,
279 				 unsigned int *link_id)
280 {
281 	struct ieee80211_local *local = hw_to_local(hw);
282 	struct link_sta_info *link_sta;
283 	struct rhlist_head *tmp;
284 
285 	for_each_link_sta_info(local, addr, link_sta, tmp) {
286 		struct sta_info *sta = link_sta->sta;
287 		struct ieee80211_link_data *link;
288 		u8 _link_id = link_sta->link_id;
289 
290 		if (!localaddr) {
291 			if (link_id)
292 				*link_id = _link_id;
293 			return &sta->sta;
294 		}
295 
296 		link = rcu_dereference(sta->sdata->link[_link_id]);
297 		if (!link)
298 			continue;
299 
300 		if (memcmp(link->conf->addr, localaddr, ETH_ALEN))
301 			continue;
302 
303 		if (link_id)
304 			*link_id = _link_id;
305 		return &sta->sta;
306 	}
307 
308 	return NULL;
309 }
310 EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_link_addrs);
311 
312 struct sta_info *sta_info_get_by_addrs(struct ieee80211_local *local,
313 				       const u8 *sta_addr, const u8 *vif_addr)
314 {
315 	struct rhlist_head *tmp;
316 	struct sta_info *sta;
317 
318 	for_each_sta_info(local, sta_addr, sta, tmp) {
319 		if (ether_addr_equal(vif_addr, sta->sdata->vif.addr))
320 			return sta;
321 	}
322 
323 	return NULL;
324 }
325 
326 struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
327 				     int idx)
328 {
329 	struct ieee80211_local *local = sdata->local;
330 	struct sta_info *sta;
331 	int i = 0;
332 
333 	list_for_each_entry_rcu(sta, &local->sta_list, list,
334 				lockdep_is_held(&local->sta_mtx)) {
335 		if (sdata != sta->sdata)
336 			continue;
337 		if (i < idx) {
338 			++i;
339 			continue;
340 		}
341 		return sta;
342 	}
343 
344 	return NULL;
345 }
346 
347 static void sta_info_free_link(struct link_sta_info *link_sta)
348 {
349 	free_percpu(link_sta->pcpu_rx_stats);
350 }
351 
352 static void sta_remove_link(struct sta_info *sta, unsigned int link_id,
353 			    bool unhash)
354 {
355 	struct sta_link_alloc *alloc = NULL;
356 	struct link_sta_info *link_sta;
357 
358 	link_sta = rcu_dereference_protected(sta->link[link_id],
359 					     lockdep_is_held(&sta->local->sta_mtx));
360 
361 	if (WARN_ON(!link_sta))
362 		return;
363 
364 	if (unhash)
365 		link_sta_info_hash_del(sta->local, link_sta);
366 
367 	if (test_sta_flag(sta, WLAN_STA_INSERTED))
368 		ieee80211_link_sta_debugfs_remove(link_sta);
369 
370 	if (link_sta != &sta->deflink)
371 		alloc = container_of(link_sta, typeof(*alloc), info);
372 
373 	sta->sta.valid_links &= ~BIT(link_id);
374 	RCU_INIT_POINTER(sta->link[link_id], NULL);
375 	RCU_INIT_POINTER(sta->sta.link[link_id], NULL);
376 	if (alloc) {
377 		sta_info_free_link(&alloc->info);
378 		kfree_rcu(alloc, rcu_head);
379 	}
380 
381 	ieee80211_sta_recalc_aggregates(&sta->sta);
382 }
383 
384 /**
385  * sta_info_free - free STA
386  *
387  * @local: pointer to the global information
388  * @sta: STA info to free
389  *
390  * This function must undo everything done by sta_info_alloc()
391  * that may happen before sta_info_insert(). It may only be
392  * called when sta_info_insert() has not been attempted (and
393  * if that fails, the station is freed anyway.)
394  */
395 void sta_info_free(struct ieee80211_local *local, struct sta_info *sta)
396 {
397 	int i;
398 
399 	for (i = 0; i < ARRAY_SIZE(sta->link); i++) {
400 		if (!(sta->sta.valid_links & BIT(i)))
401 			continue;
402 
403 		sta_remove_link(sta, i, false);
404 	}
405 
406 	/*
407 	 * If we had used sta_info_pre_move_state() then we might not
408 	 * have gone through the state transitions down again, so do
409 	 * it here now (and warn if it's inserted).
410 	 *
411 	 * This will clear state such as fast TX/RX that may have been
412 	 * allocated during state transitions.
413 	 */
414 	while (sta->sta_state > IEEE80211_STA_NONE) {
415 		int ret;
416 
417 		WARN_ON_ONCE(test_sta_flag(sta, WLAN_STA_INSERTED));
418 
419 		ret = sta_info_move_state(sta, sta->sta_state - 1);
420 		if (WARN_ONCE(ret, "sta_info_move_state() returned %d\n", ret))
421 			break;
422 	}
423 
424 	if (sta->rate_ctrl)
425 		rate_control_free_sta(sta);
426 
427 	sta_dbg(sta->sdata, "Destroyed STA %pM\n", sta->sta.addr);
428 
429 	kfree(to_txq_info(sta->sta.txq[0]));
430 	kfree(rcu_dereference_raw(sta->sta.rates));
431 #ifdef CONFIG_MAC80211_MESH
432 	kfree(sta->mesh);
433 #endif
434 
435 	sta_info_free_link(&sta->deflink);
436 	kfree(sta);
437 }
438 
439 /* Caller must hold local->sta_mtx */
440 static int sta_info_hash_add(struct ieee80211_local *local,
441 			     struct sta_info *sta)
442 {
443 	return rhltable_insert(&local->sta_hash, &sta->hash_node,
444 			       sta_rht_params);
445 }
446 
447 static void sta_deliver_ps_frames(struct work_struct *wk)
448 {
449 	struct sta_info *sta;
450 
451 	sta = container_of(wk, struct sta_info, drv_deliver_wk);
452 
453 	if (sta->dead)
454 		return;
455 
456 	local_bh_disable();
457 	if (!test_sta_flag(sta, WLAN_STA_PS_STA))
458 		ieee80211_sta_ps_deliver_wakeup(sta);
459 	else if (test_and_clear_sta_flag(sta, WLAN_STA_PSPOLL))
460 		ieee80211_sta_ps_deliver_poll_response(sta);
461 	else if (test_and_clear_sta_flag(sta, WLAN_STA_UAPSD))
462 		ieee80211_sta_ps_deliver_uapsd(sta);
463 	local_bh_enable();
464 }
465 
466 static int sta_prepare_rate_control(struct ieee80211_local *local,
467 				    struct sta_info *sta, gfp_t gfp)
468 {
469 	if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL))
470 		return 0;
471 
472 	sta->rate_ctrl = local->rate_ctrl;
473 	sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
474 						     sta, gfp);
475 	if (!sta->rate_ctrl_priv)
476 		return -ENOMEM;
477 
478 	return 0;
479 }
480 
481 static int sta_info_alloc_link(struct ieee80211_local *local,
482 			       struct link_sta_info *link_info,
483 			       gfp_t gfp)
484 {
485 	struct ieee80211_hw *hw = &local->hw;
486 	int i;
487 
488 	if (ieee80211_hw_check(hw, USES_RSS)) {
489 		link_info->pcpu_rx_stats =
490 			alloc_percpu_gfp(struct ieee80211_sta_rx_stats, gfp);
491 		if (!link_info->pcpu_rx_stats)
492 			return -ENOMEM;
493 	}
494 
495 	link_info->rx_stats.last_rx = jiffies;
496 	u64_stats_init(&link_info->rx_stats.syncp);
497 
498 	ewma_signal_init(&link_info->rx_stats_avg.signal);
499 	ewma_avg_signal_init(&link_info->status_stats.avg_ack_signal);
500 	for (i = 0; i < ARRAY_SIZE(link_info->rx_stats_avg.chain_signal); i++)
501 		ewma_signal_init(&link_info->rx_stats_avg.chain_signal[i]);
502 
503 	return 0;
504 }
505 
506 static void sta_info_add_link(struct sta_info *sta,
507 			      unsigned int link_id,
508 			      struct link_sta_info *link_info,
509 			      struct ieee80211_link_sta *link_sta)
510 {
511 	link_info->sta = sta;
512 	link_info->link_id = link_id;
513 	link_info->pub = link_sta;
514 	link_info->pub->sta = &sta->sta;
515 	link_sta->link_id = link_id;
516 	rcu_assign_pointer(sta->link[link_id], link_info);
517 	rcu_assign_pointer(sta->sta.link[link_id], link_sta);
518 
519 	link_sta->smps_mode = IEEE80211_SMPS_OFF;
520 	link_sta->agg.max_rc_amsdu_len = IEEE80211_MAX_MPDU_LEN_HT_BA;
521 }
522 
523 static struct sta_info *
524 __sta_info_alloc(struct ieee80211_sub_if_data *sdata,
525 		 const u8 *addr, int link_id, const u8 *link_addr,
526 		 gfp_t gfp)
527 {
528 	struct ieee80211_local *local = sdata->local;
529 	struct ieee80211_hw *hw = &local->hw;
530 	struct sta_info *sta;
531 	void *txq_data;
532 	int size;
533 	int i;
534 
535 	sta = kzalloc(sizeof(*sta) + hw->sta_data_size, gfp);
536 	if (!sta)
537 		return NULL;
538 
539 	sta->local = local;
540 	sta->sdata = sdata;
541 
542 	if (sta_info_alloc_link(local, &sta->deflink, gfp))
543 		goto free;
544 
545 	if (link_id >= 0) {
546 		sta_info_add_link(sta, link_id, &sta->deflink,
547 				  &sta->sta.deflink);
548 		sta->sta.valid_links = BIT(link_id);
549 	} else {
550 		sta_info_add_link(sta, 0, &sta->deflink, &sta->sta.deflink);
551 	}
552 
553 	sta->sta.cur = &sta->sta.deflink.agg;
554 
555 	spin_lock_init(&sta->lock);
556 	spin_lock_init(&sta->ps_lock);
557 	INIT_WORK(&sta->drv_deliver_wk, sta_deliver_ps_frames);
558 	INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work);
559 	mutex_init(&sta->ampdu_mlme.mtx);
560 #ifdef CONFIG_MAC80211_MESH
561 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
562 		sta->mesh = kzalloc(sizeof(*sta->mesh), gfp);
563 		if (!sta->mesh)
564 			goto free;
565 		sta->mesh->plink_sta = sta;
566 		spin_lock_init(&sta->mesh->plink_lock);
567 		if (!sdata->u.mesh.user_mpm)
568 			timer_setup(&sta->mesh->plink_timer, mesh_plink_timer,
569 				    0);
570 		sta->mesh->nonpeer_pm = NL80211_MESH_POWER_ACTIVE;
571 	}
572 #endif
573 
574 	memcpy(sta->addr, addr, ETH_ALEN);
575 	memcpy(sta->sta.addr, addr, ETH_ALEN);
576 	memcpy(sta->deflink.addr, link_addr, ETH_ALEN);
577 	memcpy(sta->sta.deflink.addr, link_addr, ETH_ALEN);
578 	sta->sta.max_rx_aggregation_subframes =
579 		local->hw.max_rx_aggregation_subframes;
580 
581 	/* TODO link specific alloc and assignments for MLO Link STA */
582 
583 	/* Extended Key ID needs to install keys for keyid 0 and 1 Rx-only.
584 	 * The Tx path starts to use a key as soon as the key slot ptk_idx
585 	 * references to is not NULL. To not use the initial Rx-only key
586 	 * prematurely for Tx initialize ptk_idx to an impossible PTK keyid
587 	 * which always will refer to a NULL key.
588 	 */
589 	BUILD_BUG_ON(ARRAY_SIZE(sta->ptk) <= INVALID_PTK_KEYIDX);
590 	sta->ptk_idx = INVALID_PTK_KEYIDX;
591 
592 
593 	ieee80211_init_frag_cache(&sta->frags);
594 
595 	sta->sta_state = IEEE80211_STA_NONE;
596 
597 	if (sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
598 		sta->amsdu_mesh_control = -1;
599 
600 	/* Mark TID as unreserved */
601 	sta->reserved_tid = IEEE80211_TID_UNRESERVED;
602 
603 	sta->last_connected = ktime_get_seconds();
604 
605 	size = sizeof(struct txq_info) +
606 	       ALIGN(hw->txq_data_size, sizeof(void *));
607 
608 	txq_data = kcalloc(ARRAY_SIZE(sta->sta.txq), size, gfp);
609 	if (!txq_data)
610 		goto free;
611 
612 	for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) {
613 		struct txq_info *txq = txq_data + i * size;
614 
615 		/* might not do anything for the (bufferable) MMPDU TXQ */
616 		ieee80211_txq_init(sdata, sta, txq, i);
617 	}
618 
619 	if (sta_prepare_rate_control(local, sta, gfp))
620 		goto free_txq;
621 
622 	sta->airtime_weight = IEEE80211_DEFAULT_AIRTIME_WEIGHT;
623 
624 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
625 		skb_queue_head_init(&sta->ps_tx_buf[i]);
626 		skb_queue_head_init(&sta->tx_filtered[i]);
627 		sta->airtime[i].deficit = sta->airtime_weight;
628 		atomic_set(&sta->airtime[i].aql_tx_pending, 0);
629 		sta->airtime[i].aql_limit_low = local->aql_txq_limit_low[i];
630 		sta->airtime[i].aql_limit_high = local->aql_txq_limit_high[i];
631 	}
632 
633 	for (i = 0; i < IEEE80211_NUM_TIDS; i++)
634 		sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX);
635 
636 	for (i = 0; i < NUM_NL80211_BANDS; i++) {
637 		u32 mandatory = 0;
638 		int r;
639 
640 		if (!hw->wiphy->bands[i])
641 			continue;
642 
643 		switch (i) {
644 		case NL80211_BAND_2GHZ:
645 		case NL80211_BAND_LC:
646 			/*
647 			 * We use both here, even if we cannot really know for
648 			 * sure the station will support both, but the only use
649 			 * for this is when we don't know anything yet and send
650 			 * management frames, and then we'll pick the lowest
651 			 * possible rate anyway.
652 			 * If we don't include _G here, we cannot find a rate
653 			 * in P2P, and thus trigger the WARN_ONCE() in rate.c
654 			 */
655 			mandatory = IEEE80211_RATE_MANDATORY_B |
656 				    IEEE80211_RATE_MANDATORY_G;
657 			break;
658 		case NL80211_BAND_5GHZ:
659 			mandatory = IEEE80211_RATE_MANDATORY_A;
660 			break;
661 		case NL80211_BAND_60GHZ:
662 			WARN_ON(1);
663 			mandatory = 0;
664 			break;
665 		}
666 
667 		for (r = 0; r < hw->wiphy->bands[i]->n_bitrates; r++) {
668 			struct ieee80211_rate *rate;
669 
670 			rate = &hw->wiphy->bands[i]->bitrates[r];
671 
672 			if (!(rate->flags & mandatory))
673 				continue;
674 			sta->sta.deflink.supp_rates[i] |= BIT(r);
675 		}
676 	}
677 
678 	sta->cparams.ce_threshold = CODEL_DISABLED_THRESHOLD;
679 	sta->cparams.target = MS2TIME(20);
680 	sta->cparams.interval = MS2TIME(100);
681 	sta->cparams.ecn = true;
682 	sta->cparams.ce_threshold_selector = 0;
683 	sta->cparams.ce_threshold_mask = 0;
684 
685 	sta_dbg(sdata, "Allocated STA %pM\n", sta->sta.addr);
686 
687 	return sta;
688 
689 free_txq:
690 	kfree(to_txq_info(sta->sta.txq[0]));
691 free:
692 	sta_info_free_link(&sta->deflink);
693 #ifdef CONFIG_MAC80211_MESH
694 	kfree(sta->mesh);
695 #endif
696 	kfree(sta);
697 	return NULL;
698 }
699 
700 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
701 				const u8 *addr, gfp_t gfp)
702 {
703 	return __sta_info_alloc(sdata, addr, -1, addr, gfp);
704 }
705 
706 struct sta_info *sta_info_alloc_with_link(struct ieee80211_sub_if_data *sdata,
707 					  const u8 *mld_addr,
708 					  unsigned int link_id,
709 					  const u8 *link_addr,
710 					  gfp_t gfp)
711 {
712 	return __sta_info_alloc(sdata, mld_addr, link_id, link_addr, gfp);
713 }
714 
715 static int sta_info_insert_check(struct sta_info *sta)
716 {
717 	struct ieee80211_sub_if_data *sdata = sta->sdata;
718 
719 	/*
720 	 * Can't be a WARN_ON because it can be triggered through a race:
721 	 * something inserts a STA (on one CPU) without holding the RTNL
722 	 * and another CPU turns off the net device.
723 	 */
724 	if (unlikely(!ieee80211_sdata_running(sdata)))
725 		return -ENETDOWN;
726 
727 	if (WARN_ON(ether_addr_equal(sta->sta.addr, sdata->vif.addr) ||
728 		    !is_valid_ether_addr(sta->sta.addr)))
729 		return -EINVAL;
730 
731 	/* The RCU read lock is required by rhashtable due to
732 	 * asynchronous resize/rehash.  We also require the mutex
733 	 * for correctness.
734 	 */
735 	rcu_read_lock();
736 	lockdep_assert_held(&sdata->local->sta_mtx);
737 	if (ieee80211_hw_check(&sdata->local->hw, NEEDS_UNIQUE_STA_ADDR) &&
738 	    ieee80211_find_sta_by_ifaddr(&sdata->local->hw, sta->addr, NULL)) {
739 		rcu_read_unlock();
740 		return -ENOTUNIQ;
741 	}
742 	rcu_read_unlock();
743 
744 	return 0;
745 }
746 
747 static int sta_info_insert_drv_state(struct ieee80211_local *local,
748 				     struct ieee80211_sub_if_data *sdata,
749 				     struct sta_info *sta)
750 {
751 	enum ieee80211_sta_state state;
752 	int err = 0;
753 
754 	for (state = IEEE80211_STA_NOTEXIST; state < sta->sta_state; state++) {
755 		err = drv_sta_state(local, sdata, sta, state, state + 1);
756 		if (err)
757 			break;
758 	}
759 
760 	if (!err) {
761 		/*
762 		 * Drivers using legacy sta_add/sta_remove callbacks only
763 		 * get uploaded set to true after sta_add is called.
764 		 */
765 		if (!local->ops->sta_add)
766 			sta->uploaded = true;
767 		return 0;
768 	}
769 
770 	if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
771 		sdata_info(sdata,
772 			   "failed to move IBSS STA %pM to state %d (%d) - keeping it anyway\n",
773 			   sta->sta.addr, state + 1, err);
774 		err = 0;
775 	}
776 
777 	/* unwind on error */
778 	for (; state > IEEE80211_STA_NOTEXIST; state--)
779 		WARN_ON(drv_sta_state(local, sdata, sta, state, state - 1));
780 
781 	return err;
782 }
783 
784 static void
785 ieee80211_recalc_p2p_go_ps_allowed(struct ieee80211_sub_if_data *sdata)
786 {
787 	struct ieee80211_local *local = sdata->local;
788 	bool allow_p2p_go_ps = sdata->vif.p2p;
789 	struct sta_info *sta;
790 
791 	rcu_read_lock();
792 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
793 		if (sdata != sta->sdata ||
794 		    !test_sta_flag(sta, WLAN_STA_ASSOC))
795 			continue;
796 		if (!sta->sta.support_p2p_ps) {
797 			allow_p2p_go_ps = false;
798 			break;
799 		}
800 	}
801 	rcu_read_unlock();
802 
803 	if (allow_p2p_go_ps != sdata->vif.bss_conf.allow_p2p_go_ps) {
804 		sdata->vif.bss_conf.allow_p2p_go_ps = allow_p2p_go_ps;
805 		ieee80211_link_info_change_notify(sdata, &sdata->deflink,
806 						  BSS_CHANGED_P2P_PS);
807 	}
808 }
809 
810 /*
811  * should be called with sta_mtx locked
812  * this function replaces the mutex lock
813  * with a RCU lock
814  */
815 static int sta_info_insert_finish(struct sta_info *sta) __acquires(RCU)
816 {
817 	struct ieee80211_local *local = sta->local;
818 	struct ieee80211_sub_if_data *sdata = sta->sdata;
819 	struct station_info *sinfo = NULL;
820 	int err = 0;
821 
822 	lockdep_assert_held(&local->sta_mtx);
823 
824 	/* check if STA exists already */
825 	if (sta_info_get_bss(sdata, sta->sta.addr)) {
826 		err = -EEXIST;
827 		goto out_cleanup;
828 	}
829 
830 	sinfo = kzalloc(sizeof(struct station_info), GFP_KERNEL);
831 	if (!sinfo) {
832 		err = -ENOMEM;
833 		goto out_cleanup;
834 	}
835 
836 	local->num_sta++;
837 	local->sta_generation++;
838 	smp_mb();
839 
840 	/* simplify things and don't accept BA sessions yet */
841 	set_sta_flag(sta, WLAN_STA_BLOCK_BA);
842 
843 	/* make the station visible */
844 	err = sta_info_hash_add(local, sta);
845 	if (err)
846 		goto out_drop_sta;
847 
848 	if (sta->sta.valid_links) {
849 		err = link_sta_info_hash_add(local, &sta->deflink);
850 		if (err) {
851 			sta_info_hash_del(local, sta);
852 			goto out_drop_sta;
853 		}
854 	}
855 
856 	list_add_tail_rcu(&sta->list, &local->sta_list);
857 
858 	/* update channel context before notifying the driver about state
859 	 * change, this enables driver using the updated channel context right away.
860 	 */
861 	if (sta->sta_state >= IEEE80211_STA_ASSOC) {
862 		ieee80211_recalc_min_chandef(sta->sdata, -1);
863 		if (!sta->sta.support_p2p_ps)
864 			ieee80211_recalc_p2p_go_ps_allowed(sta->sdata);
865 	}
866 
867 	/* notify driver */
868 	err = sta_info_insert_drv_state(local, sdata, sta);
869 	if (err)
870 		goto out_remove;
871 
872 	set_sta_flag(sta, WLAN_STA_INSERTED);
873 
874 	/* accept BA sessions now */
875 	clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
876 
877 	ieee80211_sta_debugfs_add(sta);
878 	rate_control_add_sta_debugfs(sta);
879 	if (sta->sta.valid_links) {
880 		int i;
881 
882 		for (i = 0; i < ARRAY_SIZE(sta->link); i++) {
883 			struct link_sta_info *link_sta;
884 
885 			link_sta = rcu_dereference_protected(sta->link[i],
886 							     lockdep_is_held(&local->sta_mtx));
887 
888 			if (!link_sta)
889 				continue;
890 
891 			ieee80211_link_sta_debugfs_add(link_sta);
892 			if (sdata->vif.active_links & BIT(i))
893 				ieee80211_link_sta_debugfs_drv_add(link_sta);
894 		}
895 	} else {
896 		ieee80211_link_sta_debugfs_add(&sta->deflink);
897 		ieee80211_link_sta_debugfs_drv_add(&sta->deflink);
898 	}
899 
900 	sinfo->generation = local->sta_generation;
901 	cfg80211_new_sta(sdata->dev, sta->sta.addr, sinfo, GFP_KERNEL);
902 	kfree(sinfo);
903 
904 	sta_dbg(sdata, "Inserted STA %pM\n", sta->sta.addr);
905 
906 	/* move reference to rcu-protected */
907 	rcu_read_lock();
908 	mutex_unlock(&local->sta_mtx);
909 
910 	if (ieee80211_vif_is_mesh(&sdata->vif))
911 		mesh_accept_plinks_update(sdata);
912 
913 	return 0;
914  out_remove:
915 	if (sta->sta.valid_links)
916 		link_sta_info_hash_del(local, &sta->deflink);
917 	sta_info_hash_del(local, sta);
918 	list_del_rcu(&sta->list);
919  out_drop_sta:
920 	local->num_sta--;
921 	synchronize_net();
922  out_cleanup:
923 	cleanup_single_sta(sta);
924 	mutex_unlock(&local->sta_mtx);
925 	kfree(sinfo);
926 	rcu_read_lock();
927 	return err;
928 }
929 
930 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU)
931 {
932 	struct ieee80211_local *local = sta->local;
933 	int err;
934 
935 	might_sleep();
936 
937 	mutex_lock(&local->sta_mtx);
938 
939 	err = sta_info_insert_check(sta);
940 	if (err) {
941 		sta_info_free(local, sta);
942 		mutex_unlock(&local->sta_mtx);
943 		rcu_read_lock();
944 		return err;
945 	}
946 
947 	return sta_info_insert_finish(sta);
948 }
949 
950 int sta_info_insert(struct sta_info *sta)
951 {
952 	int err = sta_info_insert_rcu(sta);
953 
954 	rcu_read_unlock();
955 
956 	return err;
957 }
958 
959 static inline void __bss_tim_set(u8 *tim, u16 id)
960 {
961 	/*
962 	 * This format has been mandated by the IEEE specifications,
963 	 * so this line may not be changed to use the __set_bit() format.
964 	 */
965 	tim[id / 8] |= (1 << (id % 8));
966 }
967 
968 static inline void __bss_tim_clear(u8 *tim, u16 id)
969 {
970 	/*
971 	 * This format has been mandated by the IEEE specifications,
972 	 * so this line may not be changed to use the __clear_bit() format.
973 	 */
974 	tim[id / 8] &= ~(1 << (id % 8));
975 }
976 
977 static inline bool __bss_tim_get(u8 *tim, u16 id)
978 {
979 	/*
980 	 * This format has been mandated by the IEEE specifications,
981 	 * so this line may not be changed to use the test_bit() format.
982 	 */
983 	return tim[id / 8] & (1 << (id % 8));
984 }
985 
986 static unsigned long ieee80211_tids_for_ac(int ac)
987 {
988 	/* If we ever support TIDs > 7, this obviously needs to be adjusted */
989 	switch (ac) {
990 	case IEEE80211_AC_VO:
991 		return BIT(6) | BIT(7);
992 	case IEEE80211_AC_VI:
993 		return BIT(4) | BIT(5);
994 	case IEEE80211_AC_BE:
995 		return BIT(0) | BIT(3);
996 	case IEEE80211_AC_BK:
997 		return BIT(1) | BIT(2);
998 	default:
999 		WARN_ON(1);
1000 		return 0;
1001 	}
1002 }
1003 
1004 static void __sta_info_recalc_tim(struct sta_info *sta, bool ignore_pending)
1005 {
1006 	struct ieee80211_local *local = sta->local;
1007 	struct ps_data *ps;
1008 	bool indicate_tim = false;
1009 	u8 ignore_for_tim = sta->sta.uapsd_queues;
1010 	int ac;
1011 	u16 id = sta->sta.aid;
1012 
1013 	if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1014 	    sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
1015 		if (WARN_ON_ONCE(!sta->sdata->bss))
1016 			return;
1017 
1018 		ps = &sta->sdata->bss->ps;
1019 #ifdef CONFIG_MAC80211_MESH
1020 	} else if (ieee80211_vif_is_mesh(&sta->sdata->vif)) {
1021 		ps = &sta->sdata->u.mesh.ps;
1022 #endif
1023 	} else {
1024 		return;
1025 	}
1026 
1027 	/* No need to do anything if the driver does all */
1028 	if (ieee80211_hw_check(&local->hw, AP_LINK_PS) && !local->ops->set_tim)
1029 		return;
1030 
1031 	if (sta->dead)
1032 		goto done;
1033 
1034 	/*
1035 	 * If all ACs are delivery-enabled then we should build
1036 	 * the TIM bit for all ACs anyway; if only some are then
1037 	 * we ignore those and build the TIM bit using only the
1038 	 * non-enabled ones.
1039 	 */
1040 	if (ignore_for_tim == BIT(IEEE80211_NUM_ACS) - 1)
1041 		ignore_for_tim = 0;
1042 
1043 	if (ignore_pending)
1044 		ignore_for_tim = BIT(IEEE80211_NUM_ACS) - 1;
1045 
1046 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
1047 		unsigned long tids;
1048 
1049 		if (ignore_for_tim & ieee80211_ac_to_qos_mask[ac])
1050 			continue;
1051 
1052 		indicate_tim |= !skb_queue_empty(&sta->tx_filtered[ac]) ||
1053 				!skb_queue_empty(&sta->ps_tx_buf[ac]);
1054 		if (indicate_tim)
1055 			break;
1056 
1057 		tids = ieee80211_tids_for_ac(ac);
1058 
1059 		indicate_tim |=
1060 			sta->driver_buffered_tids & tids;
1061 		indicate_tim |=
1062 			sta->txq_buffered_tids & tids;
1063 	}
1064 
1065  done:
1066 	spin_lock_bh(&local->tim_lock);
1067 
1068 	if (indicate_tim == __bss_tim_get(ps->tim, id))
1069 		goto out_unlock;
1070 
1071 	if (indicate_tim)
1072 		__bss_tim_set(ps->tim, id);
1073 	else
1074 		__bss_tim_clear(ps->tim, id);
1075 
1076 	if (local->ops->set_tim && !WARN_ON(sta->dead)) {
1077 		local->tim_in_locked_section = true;
1078 		drv_set_tim(local, &sta->sta, indicate_tim);
1079 		local->tim_in_locked_section = false;
1080 	}
1081 
1082 out_unlock:
1083 	spin_unlock_bh(&local->tim_lock);
1084 }
1085 
1086 void sta_info_recalc_tim(struct sta_info *sta)
1087 {
1088 	__sta_info_recalc_tim(sta, false);
1089 }
1090 
1091 static bool sta_info_buffer_expired(struct sta_info *sta, struct sk_buff *skb)
1092 {
1093 	struct ieee80211_tx_info *info;
1094 	int timeout;
1095 
1096 	if (!skb)
1097 		return false;
1098 
1099 	info = IEEE80211_SKB_CB(skb);
1100 
1101 	/* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
1102 	timeout = (sta->listen_interval *
1103 		   sta->sdata->vif.bss_conf.beacon_int *
1104 		   32 / 15625) * HZ;
1105 	if (timeout < STA_TX_BUFFER_EXPIRE)
1106 		timeout = STA_TX_BUFFER_EXPIRE;
1107 	return time_after(jiffies, info->control.jiffies + timeout);
1108 }
1109 
1110 
1111 static bool sta_info_cleanup_expire_buffered_ac(struct ieee80211_local *local,
1112 						struct sta_info *sta, int ac)
1113 {
1114 	unsigned long flags;
1115 	struct sk_buff *skb;
1116 
1117 	/*
1118 	 * First check for frames that should expire on the filtered
1119 	 * queue. Frames here were rejected by the driver and are on
1120 	 * a separate queue to avoid reordering with normal PS-buffered
1121 	 * frames. They also aren't accounted for right now in the
1122 	 * total_ps_buffered counter.
1123 	 */
1124 	for (;;) {
1125 		spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
1126 		skb = skb_peek(&sta->tx_filtered[ac]);
1127 		if (sta_info_buffer_expired(sta, skb))
1128 			skb = __skb_dequeue(&sta->tx_filtered[ac]);
1129 		else
1130 			skb = NULL;
1131 		spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
1132 
1133 		/*
1134 		 * Frames are queued in order, so if this one
1135 		 * hasn't expired yet we can stop testing. If
1136 		 * we actually reached the end of the queue we
1137 		 * also need to stop, of course.
1138 		 */
1139 		if (!skb)
1140 			break;
1141 		ieee80211_free_txskb(&local->hw, skb);
1142 	}
1143 
1144 	/*
1145 	 * Now also check the normal PS-buffered queue, this will
1146 	 * only find something if the filtered queue was emptied
1147 	 * since the filtered frames are all before the normal PS
1148 	 * buffered frames.
1149 	 */
1150 	for (;;) {
1151 		spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
1152 		skb = skb_peek(&sta->ps_tx_buf[ac]);
1153 		if (sta_info_buffer_expired(sta, skb))
1154 			skb = __skb_dequeue(&sta->ps_tx_buf[ac]);
1155 		else
1156 			skb = NULL;
1157 		spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
1158 
1159 		/*
1160 		 * frames are queued in order, so if this one
1161 		 * hasn't expired yet (or we reached the end of
1162 		 * the queue) we can stop testing
1163 		 */
1164 		if (!skb)
1165 			break;
1166 
1167 		local->total_ps_buffered--;
1168 		ps_dbg(sta->sdata, "Buffered frame expired (STA %pM)\n",
1169 		       sta->sta.addr);
1170 		ieee80211_free_txskb(&local->hw, skb);
1171 	}
1172 
1173 	/*
1174 	 * Finally, recalculate the TIM bit for this station -- it might
1175 	 * now be clear because the station was too slow to retrieve its
1176 	 * frames.
1177 	 */
1178 	sta_info_recalc_tim(sta);
1179 
1180 	/*
1181 	 * Return whether there are any frames still buffered, this is
1182 	 * used to check whether the cleanup timer still needs to run,
1183 	 * if there are no frames we don't need to rearm the timer.
1184 	 */
1185 	return !(skb_queue_empty(&sta->ps_tx_buf[ac]) &&
1186 		 skb_queue_empty(&sta->tx_filtered[ac]));
1187 }
1188 
1189 static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
1190 					     struct sta_info *sta)
1191 {
1192 	bool have_buffered = false;
1193 	int ac;
1194 
1195 	/* This is only necessary for stations on BSS/MBSS interfaces */
1196 	if (!sta->sdata->bss &&
1197 	    !ieee80211_vif_is_mesh(&sta->sdata->vif))
1198 		return false;
1199 
1200 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
1201 		have_buffered |=
1202 			sta_info_cleanup_expire_buffered_ac(local, sta, ac);
1203 
1204 	return have_buffered;
1205 }
1206 
1207 static int __must_check __sta_info_destroy_part1(struct sta_info *sta)
1208 {
1209 	struct ieee80211_local *local;
1210 	struct ieee80211_sub_if_data *sdata;
1211 	int ret, i;
1212 
1213 	might_sleep();
1214 
1215 	if (!sta)
1216 		return -ENOENT;
1217 
1218 	local = sta->local;
1219 	sdata = sta->sdata;
1220 
1221 	lockdep_assert_held(&local->sta_mtx);
1222 
1223 	/*
1224 	 * Before removing the station from the driver and
1225 	 * rate control, it might still start new aggregation
1226 	 * sessions -- block that to make sure the tear-down
1227 	 * will be sufficient.
1228 	 */
1229 	set_sta_flag(sta, WLAN_STA_BLOCK_BA);
1230 	ieee80211_sta_tear_down_BA_sessions(sta, AGG_STOP_DESTROY_STA);
1231 
1232 	/*
1233 	 * Before removing the station from the driver there might be pending
1234 	 * rx frames on RSS queues sent prior to the disassociation - wait for
1235 	 * all such frames to be processed.
1236 	 */
1237 	drv_sync_rx_queues(local, sta);
1238 
1239 	for (i = 0; i < ARRAY_SIZE(sta->link); i++) {
1240 		struct link_sta_info *link_sta;
1241 
1242 		if (!(sta->sta.valid_links & BIT(i)))
1243 			continue;
1244 
1245 		link_sta = rcu_dereference_protected(sta->link[i],
1246 						     lockdep_is_held(&local->sta_mtx));
1247 
1248 		link_sta_info_hash_del(local, link_sta);
1249 	}
1250 
1251 	ret = sta_info_hash_del(local, sta);
1252 	if (WARN_ON(ret))
1253 		return ret;
1254 
1255 	/*
1256 	 * for TDLS peers, make sure to return to the base channel before
1257 	 * removal.
1258 	 */
1259 	if (test_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL)) {
1260 		drv_tdls_cancel_channel_switch(local, sdata, &sta->sta);
1261 		clear_sta_flag(sta, WLAN_STA_TDLS_OFF_CHANNEL);
1262 	}
1263 
1264 	list_del_rcu(&sta->list);
1265 	sta->removed = true;
1266 
1267 	drv_sta_pre_rcu_remove(local, sta->sdata, sta);
1268 
1269 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1270 	    rcu_access_pointer(sdata->u.vlan.sta) == sta)
1271 		RCU_INIT_POINTER(sdata->u.vlan.sta, NULL);
1272 
1273 	return 0;
1274 }
1275 
1276 static void __sta_info_destroy_part2(struct sta_info *sta)
1277 {
1278 	struct ieee80211_local *local = sta->local;
1279 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1280 	struct station_info *sinfo;
1281 	int ret;
1282 
1283 	/*
1284 	 * NOTE: This assumes at least synchronize_net() was done
1285 	 *	 after _part1 and before _part2!
1286 	 */
1287 
1288 	might_sleep();
1289 	lockdep_assert_held(&local->sta_mtx);
1290 
1291 	if (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
1292 		ret = sta_info_move_state(sta, IEEE80211_STA_ASSOC);
1293 		WARN_ON_ONCE(ret);
1294 	}
1295 
1296 	/* now keys can no longer be reached */
1297 	ieee80211_free_sta_keys(local, sta);
1298 
1299 	/* disable TIM bit - last chance to tell driver */
1300 	__sta_info_recalc_tim(sta, true);
1301 
1302 	sta->dead = true;
1303 
1304 	local->num_sta--;
1305 	local->sta_generation++;
1306 
1307 	while (sta->sta_state > IEEE80211_STA_NONE) {
1308 		ret = sta_info_move_state(sta, sta->sta_state - 1);
1309 		if (ret) {
1310 			WARN_ON_ONCE(1);
1311 			break;
1312 		}
1313 	}
1314 
1315 	if (sta->uploaded) {
1316 		ret = drv_sta_state(local, sdata, sta, IEEE80211_STA_NONE,
1317 				    IEEE80211_STA_NOTEXIST);
1318 		WARN_ON_ONCE(ret != 0);
1319 	}
1320 
1321 	sta_dbg(sdata, "Removed STA %pM\n", sta->sta.addr);
1322 
1323 	sinfo = kzalloc(sizeof(*sinfo), GFP_KERNEL);
1324 	if (sinfo)
1325 		sta_set_sinfo(sta, sinfo, true);
1326 	cfg80211_del_sta_sinfo(sdata->dev, sta->sta.addr, sinfo, GFP_KERNEL);
1327 	kfree(sinfo);
1328 
1329 	ieee80211_sta_debugfs_remove(sta);
1330 
1331 	ieee80211_destroy_frag_cache(&sta->frags);
1332 
1333 	cleanup_single_sta(sta);
1334 }
1335 
1336 int __must_check __sta_info_destroy(struct sta_info *sta)
1337 {
1338 	int err = __sta_info_destroy_part1(sta);
1339 
1340 	if (err)
1341 		return err;
1342 
1343 	synchronize_net();
1344 
1345 	__sta_info_destroy_part2(sta);
1346 
1347 	return 0;
1348 }
1349 
1350 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr)
1351 {
1352 	struct sta_info *sta;
1353 	int ret;
1354 
1355 	mutex_lock(&sdata->local->sta_mtx);
1356 	sta = sta_info_get(sdata, addr);
1357 	ret = __sta_info_destroy(sta);
1358 	mutex_unlock(&sdata->local->sta_mtx);
1359 
1360 	return ret;
1361 }
1362 
1363 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
1364 			      const u8 *addr)
1365 {
1366 	struct sta_info *sta;
1367 	int ret;
1368 
1369 	mutex_lock(&sdata->local->sta_mtx);
1370 	sta = sta_info_get_bss(sdata, addr);
1371 	ret = __sta_info_destroy(sta);
1372 	mutex_unlock(&sdata->local->sta_mtx);
1373 
1374 	return ret;
1375 }
1376 
1377 static void sta_info_cleanup(struct timer_list *t)
1378 {
1379 	struct ieee80211_local *local = from_timer(local, t, sta_cleanup);
1380 	struct sta_info *sta;
1381 	bool timer_needed = false;
1382 
1383 	rcu_read_lock();
1384 	list_for_each_entry_rcu(sta, &local->sta_list, list)
1385 		if (sta_info_cleanup_expire_buffered(local, sta))
1386 			timer_needed = true;
1387 	rcu_read_unlock();
1388 
1389 	if (local->quiescing)
1390 		return;
1391 
1392 	if (!timer_needed)
1393 		return;
1394 
1395 	mod_timer(&local->sta_cleanup,
1396 		  round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL));
1397 }
1398 
1399 int sta_info_init(struct ieee80211_local *local)
1400 {
1401 	int err;
1402 
1403 	err = rhltable_init(&local->sta_hash, &sta_rht_params);
1404 	if (err)
1405 		return err;
1406 
1407 	err = rhltable_init(&local->link_sta_hash, &link_sta_rht_params);
1408 	if (err) {
1409 		rhltable_destroy(&local->sta_hash);
1410 		return err;
1411 	}
1412 
1413 	spin_lock_init(&local->tim_lock);
1414 	mutex_init(&local->sta_mtx);
1415 	INIT_LIST_HEAD(&local->sta_list);
1416 
1417 	timer_setup(&local->sta_cleanup, sta_info_cleanup, 0);
1418 	return 0;
1419 }
1420 
1421 void sta_info_stop(struct ieee80211_local *local)
1422 {
1423 	del_timer_sync(&local->sta_cleanup);
1424 	rhltable_destroy(&local->sta_hash);
1425 	rhltable_destroy(&local->link_sta_hash);
1426 }
1427 
1428 
1429 int __sta_info_flush(struct ieee80211_sub_if_data *sdata, bool vlans)
1430 {
1431 	struct ieee80211_local *local = sdata->local;
1432 	struct sta_info *sta, *tmp;
1433 	LIST_HEAD(free_list);
1434 	int ret = 0;
1435 
1436 	might_sleep();
1437 
1438 	WARN_ON(vlans && sdata->vif.type != NL80211_IFTYPE_AP);
1439 	WARN_ON(vlans && !sdata->bss);
1440 
1441 	mutex_lock(&local->sta_mtx);
1442 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1443 		if (sdata == sta->sdata ||
1444 		    (vlans && sdata->bss == sta->sdata->bss)) {
1445 			if (!WARN_ON(__sta_info_destroy_part1(sta)))
1446 				list_add(&sta->free_list, &free_list);
1447 			ret++;
1448 		}
1449 	}
1450 
1451 	if (!list_empty(&free_list)) {
1452 		synchronize_net();
1453 		list_for_each_entry_safe(sta, tmp, &free_list, free_list)
1454 			__sta_info_destroy_part2(sta);
1455 	}
1456 	mutex_unlock(&local->sta_mtx);
1457 
1458 	return ret;
1459 }
1460 
1461 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
1462 			  unsigned long exp_time)
1463 {
1464 	struct ieee80211_local *local = sdata->local;
1465 	struct sta_info *sta, *tmp;
1466 
1467 	mutex_lock(&local->sta_mtx);
1468 
1469 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1470 		unsigned long last_active = ieee80211_sta_last_active(sta);
1471 
1472 		if (sdata != sta->sdata)
1473 			continue;
1474 
1475 		if (time_is_before_jiffies(last_active + exp_time)) {
1476 			sta_dbg(sta->sdata, "expiring inactive STA %pM\n",
1477 				sta->sta.addr);
1478 
1479 			if (ieee80211_vif_is_mesh(&sdata->vif) &&
1480 			    test_sta_flag(sta, WLAN_STA_PS_STA))
1481 				atomic_dec(&sdata->u.mesh.ps.num_sta_ps);
1482 
1483 			WARN_ON(__sta_info_destroy(sta));
1484 		}
1485 	}
1486 
1487 	mutex_unlock(&local->sta_mtx);
1488 }
1489 
1490 struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw,
1491 						   const u8 *addr,
1492 						   const u8 *localaddr)
1493 {
1494 	struct ieee80211_local *local = hw_to_local(hw);
1495 	struct rhlist_head *tmp;
1496 	struct sta_info *sta;
1497 
1498 	/*
1499 	 * Just return a random station if localaddr is NULL
1500 	 * ... first in list.
1501 	 */
1502 	for_each_sta_info(local, addr, sta, tmp) {
1503 		if (localaddr &&
1504 		    !ether_addr_equal(sta->sdata->vif.addr, localaddr))
1505 			continue;
1506 		if (!sta->uploaded)
1507 			return NULL;
1508 		return &sta->sta;
1509 	}
1510 
1511 	return NULL;
1512 }
1513 EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr);
1514 
1515 struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif,
1516 					 const u8 *addr)
1517 {
1518 	struct sta_info *sta;
1519 
1520 	if (!vif)
1521 		return NULL;
1522 
1523 	sta = sta_info_get_bss(vif_to_sdata(vif), addr);
1524 	if (!sta)
1525 		return NULL;
1526 
1527 	if (!sta->uploaded)
1528 		return NULL;
1529 
1530 	return &sta->sta;
1531 }
1532 EXPORT_SYMBOL(ieee80211_find_sta);
1533 
1534 /* powersave support code */
1535 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
1536 {
1537 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1538 	struct ieee80211_local *local = sdata->local;
1539 	struct sk_buff_head pending;
1540 	int filtered = 0, buffered = 0, ac, i;
1541 	unsigned long flags;
1542 	struct ps_data *ps;
1543 
1544 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
1545 		sdata = container_of(sdata->bss, struct ieee80211_sub_if_data,
1546 				     u.ap);
1547 
1548 	if (sdata->vif.type == NL80211_IFTYPE_AP)
1549 		ps = &sdata->bss->ps;
1550 	else if (ieee80211_vif_is_mesh(&sdata->vif))
1551 		ps = &sdata->u.mesh.ps;
1552 	else
1553 		return;
1554 
1555 	clear_sta_flag(sta, WLAN_STA_SP);
1556 
1557 	BUILD_BUG_ON(BITS_TO_LONGS(IEEE80211_NUM_TIDS) > 1);
1558 	sta->driver_buffered_tids = 0;
1559 	sta->txq_buffered_tids = 0;
1560 
1561 	if (!ieee80211_hw_check(&local->hw, AP_LINK_PS))
1562 		drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
1563 
1564 	for (i = 0; i < ARRAY_SIZE(sta->sta.txq); i++) {
1565 		if (!sta->sta.txq[i] || !txq_has_queue(sta->sta.txq[i]))
1566 			continue;
1567 
1568 		schedule_and_wake_txq(local, to_txq_info(sta->sta.txq[i]));
1569 	}
1570 
1571 	skb_queue_head_init(&pending);
1572 
1573 	/* sync with ieee80211_tx_h_unicast_ps_buf */
1574 	spin_lock(&sta->ps_lock);
1575 	/* Send all buffered frames to the station */
1576 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
1577 		int count = skb_queue_len(&pending), tmp;
1578 
1579 		spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
1580 		skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending);
1581 		spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
1582 		tmp = skb_queue_len(&pending);
1583 		filtered += tmp - count;
1584 		count = tmp;
1585 
1586 		spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
1587 		skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending);
1588 		spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
1589 		tmp = skb_queue_len(&pending);
1590 		buffered += tmp - count;
1591 	}
1592 
1593 	ieee80211_add_pending_skbs(local, &pending);
1594 
1595 	/* now we're no longer in the deliver code */
1596 	clear_sta_flag(sta, WLAN_STA_PS_DELIVER);
1597 
1598 	/* The station might have polled and then woken up before we responded,
1599 	 * so clear these flags now to avoid them sticking around.
1600 	 */
1601 	clear_sta_flag(sta, WLAN_STA_PSPOLL);
1602 	clear_sta_flag(sta, WLAN_STA_UAPSD);
1603 	spin_unlock(&sta->ps_lock);
1604 
1605 	atomic_dec(&ps->num_sta_ps);
1606 
1607 	local->total_ps_buffered -= buffered;
1608 
1609 	sta_info_recalc_tim(sta);
1610 
1611 	ps_dbg(sdata,
1612 	       "STA %pM aid %d sending %d filtered/%d PS frames since STA woke up\n",
1613 	       sta->sta.addr, sta->sta.aid, filtered, buffered);
1614 
1615 	ieee80211_check_fast_xmit(sta);
1616 }
1617 
1618 static void ieee80211_send_null_response(struct sta_info *sta, int tid,
1619 					 enum ieee80211_frame_release_type reason,
1620 					 bool call_driver, bool more_data)
1621 {
1622 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1623 	struct ieee80211_local *local = sdata->local;
1624 	struct ieee80211_qos_hdr *nullfunc;
1625 	struct sk_buff *skb;
1626 	int size = sizeof(*nullfunc);
1627 	__le16 fc;
1628 	bool qos = sta->sta.wme;
1629 	struct ieee80211_tx_info *info;
1630 	struct ieee80211_chanctx_conf *chanctx_conf;
1631 
1632 	if (qos) {
1633 		fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
1634 				 IEEE80211_STYPE_QOS_NULLFUNC |
1635 				 IEEE80211_FCTL_FROMDS);
1636 	} else {
1637 		size -= 2;
1638 		fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
1639 				 IEEE80211_STYPE_NULLFUNC |
1640 				 IEEE80211_FCTL_FROMDS);
1641 	}
1642 
1643 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + size);
1644 	if (!skb)
1645 		return;
1646 
1647 	skb_reserve(skb, local->hw.extra_tx_headroom);
1648 
1649 	nullfunc = skb_put(skb, size);
1650 	nullfunc->frame_control = fc;
1651 	nullfunc->duration_id = 0;
1652 	memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
1653 	memcpy(nullfunc->addr2, sdata->vif.addr, ETH_ALEN);
1654 	memcpy(nullfunc->addr3, sdata->vif.addr, ETH_ALEN);
1655 	nullfunc->seq_ctrl = 0;
1656 
1657 	skb->priority = tid;
1658 	skb_set_queue_mapping(skb, ieee802_1d_to_ac[tid]);
1659 	if (qos) {
1660 		nullfunc->qos_ctrl = cpu_to_le16(tid);
1661 
1662 		if (reason == IEEE80211_FRAME_RELEASE_UAPSD) {
1663 			nullfunc->qos_ctrl |=
1664 				cpu_to_le16(IEEE80211_QOS_CTL_EOSP);
1665 			if (more_data)
1666 				nullfunc->frame_control |=
1667 					cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1668 		}
1669 	}
1670 
1671 	info = IEEE80211_SKB_CB(skb);
1672 
1673 	/*
1674 	 * Tell TX path to send this frame even though the
1675 	 * STA may still remain is PS mode after this frame
1676 	 * exchange. Also set EOSP to indicate this packet
1677 	 * ends the poll/service period.
1678 	 */
1679 	info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER |
1680 		       IEEE80211_TX_STATUS_EOSP |
1681 		       IEEE80211_TX_CTL_REQ_TX_STATUS;
1682 
1683 	info->control.flags |= IEEE80211_TX_CTRL_PS_RESPONSE;
1684 
1685 	if (call_driver)
1686 		drv_allow_buffered_frames(local, sta, BIT(tid), 1,
1687 					  reason, false);
1688 
1689 	skb->dev = sdata->dev;
1690 
1691 	rcu_read_lock();
1692 	chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
1693 	if (WARN_ON(!chanctx_conf)) {
1694 		rcu_read_unlock();
1695 		kfree_skb(skb);
1696 		return;
1697 	}
1698 
1699 	info->band = chanctx_conf->def.chan->band;
1700 	ieee80211_xmit(sdata, sta, skb);
1701 	rcu_read_unlock();
1702 }
1703 
1704 static int find_highest_prio_tid(unsigned long tids)
1705 {
1706 	/* lower 3 TIDs aren't ordered perfectly */
1707 	if (tids & 0xF8)
1708 		return fls(tids) - 1;
1709 	/* TID 0 is BE just like TID 3 */
1710 	if (tids & BIT(0))
1711 		return 0;
1712 	return fls(tids) - 1;
1713 }
1714 
1715 /* Indicates if the MORE_DATA bit should be set in the last
1716  * frame obtained by ieee80211_sta_ps_get_frames.
1717  * Note that driver_release_tids is relevant only if
1718  * reason = IEEE80211_FRAME_RELEASE_PSPOLL
1719  */
1720 static bool
1721 ieee80211_sta_ps_more_data(struct sta_info *sta, u8 ignored_acs,
1722 			   enum ieee80211_frame_release_type reason,
1723 			   unsigned long driver_release_tids)
1724 {
1725 	int ac;
1726 
1727 	/* If the driver has data on more than one TID then
1728 	 * certainly there's more data if we release just a
1729 	 * single frame now (from a single TID). This will
1730 	 * only happen for PS-Poll.
1731 	 */
1732 	if (reason == IEEE80211_FRAME_RELEASE_PSPOLL &&
1733 	    hweight16(driver_release_tids) > 1)
1734 		return true;
1735 
1736 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
1737 		if (ignored_acs & ieee80211_ac_to_qos_mask[ac])
1738 			continue;
1739 
1740 		if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
1741 		    !skb_queue_empty(&sta->ps_tx_buf[ac]))
1742 			return true;
1743 	}
1744 
1745 	return false;
1746 }
1747 
1748 static void
1749 ieee80211_sta_ps_get_frames(struct sta_info *sta, int n_frames, u8 ignored_acs,
1750 			    enum ieee80211_frame_release_type reason,
1751 			    struct sk_buff_head *frames,
1752 			    unsigned long *driver_release_tids)
1753 {
1754 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1755 	struct ieee80211_local *local = sdata->local;
1756 	int ac;
1757 
1758 	/* Get response frame(s) and more data bit for the last one. */
1759 	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
1760 		unsigned long tids;
1761 
1762 		if (ignored_acs & ieee80211_ac_to_qos_mask[ac])
1763 			continue;
1764 
1765 		tids = ieee80211_tids_for_ac(ac);
1766 
1767 		/* if we already have frames from software, then we can't also
1768 		 * release from hardware queues
1769 		 */
1770 		if (skb_queue_empty(frames)) {
1771 			*driver_release_tids |=
1772 				sta->driver_buffered_tids & tids;
1773 			*driver_release_tids |= sta->txq_buffered_tids & tids;
1774 		}
1775 
1776 		if (!*driver_release_tids) {
1777 			struct sk_buff *skb;
1778 
1779 			while (n_frames > 0) {
1780 				skb = skb_dequeue(&sta->tx_filtered[ac]);
1781 				if (!skb) {
1782 					skb = skb_dequeue(
1783 						&sta->ps_tx_buf[ac]);
1784 					if (skb)
1785 						local->total_ps_buffered--;
1786 				}
1787 				if (!skb)
1788 					break;
1789 				n_frames--;
1790 				__skb_queue_tail(frames, skb);
1791 			}
1792 		}
1793 
1794 		/* If we have more frames buffered on this AC, then abort the
1795 		 * loop since we can't send more data from other ACs before
1796 		 * the buffered frames from this.
1797 		 */
1798 		if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
1799 		    !skb_queue_empty(&sta->ps_tx_buf[ac]))
1800 			break;
1801 	}
1802 }
1803 
1804 static void
1805 ieee80211_sta_ps_deliver_response(struct sta_info *sta,
1806 				  int n_frames, u8 ignored_acs,
1807 				  enum ieee80211_frame_release_type reason)
1808 {
1809 	struct ieee80211_sub_if_data *sdata = sta->sdata;
1810 	struct ieee80211_local *local = sdata->local;
1811 	unsigned long driver_release_tids = 0;
1812 	struct sk_buff_head frames;
1813 	bool more_data;
1814 
1815 	/* Service or PS-Poll period starts */
1816 	set_sta_flag(sta, WLAN_STA_SP);
1817 
1818 	__skb_queue_head_init(&frames);
1819 
1820 	ieee80211_sta_ps_get_frames(sta, n_frames, ignored_acs, reason,
1821 				    &frames, &driver_release_tids);
1822 
1823 	more_data = ieee80211_sta_ps_more_data(sta, ignored_acs, reason, driver_release_tids);
1824 
1825 	if (driver_release_tids && reason == IEEE80211_FRAME_RELEASE_PSPOLL)
1826 		driver_release_tids =
1827 			BIT(find_highest_prio_tid(driver_release_tids));
1828 
1829 	if (skb_queue_empty(&frames) && !driver_release_tids) {
1830 		int tid, ac;
1831 
1832 		/*
1833 		 * For PS-Poll, this can only happen due to a race condition
1834 		 * when we set the TIM bit and the station notices it, but
1835 		 * before it can poll for the frame we expire it.
1836 		 *
1837 		 * For uAPSD, this is said in the standard (11.2.1.5 h):
1838 		 *	At each unscheduled SP for a non-AP STA, the AP shall
1839 		 *	attempt to transmit at least one MSDU or MMPDU, but no
1840 		 *	more than the value specified in the Max SP Length field
1841 		 *	in the QoS Capability element from delivery-enabled ACs,
1842 		 *	that are destined for the non-AP STA.
1843 		 *
1844 		 * Since we have no other MSDU/MMPDU, transmit a QoS null frame.
1845 		 */
1846 
1847 		/* This will evaluate to 1, 3, 5 or 7. */
1848 		for (ac = IEEE80211_AC_VO; ac < IEEE80211_NUM_ACS; ac++)
1849 			if (!(ignored_acs & ieee80211_ac_to_qos_mask[ac]))
1850 				break;
1851 		tid = 7 - 2 * ac;
1852 
1853 		ieee80211_send_null_response(sta, tid, reason, true, false);
1854 	} else if (!driver_release_tids) {
1855 		struct sk_buff_head pending;
1856 		struct sk_buff *skb;
1857 		int num = 0;
1858 		u16 tids = 0;
1859 		bool need_null = false;
1860 
1861 		skb_queue_head_init(&pending);
1862 
1863 		while ((skb = __skb_dequeue(&frames))) {
1864 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1865 			struct ieee80211_hdr *hdr = (void *) skb->data;
1866 			u8 *qoshdr = NULL;
1867 
1868 			num++;
1869 
1870 			/*
1871 			 * Tell TX path to send this frame even though the
1872 			 * STA may still remain is PS mode after this frame
1873 			 * exchange.
1874 			 */
1875 			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
1876 			info->control.flags |= IEEE80211_TX_CTRL_PS_RESPONSE;
1877 
1878 			/*
1879 			 * Use MoreData flag to indicate whether there are
1880 			 * more buffered frames for this STA
1881 			 */
1882 			if (more_data || !skb_queue_empty(&frames))
1883 				hdr->frame_control |=
1884 					cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1885 			else
1886 				hdr->frame_control &=
1887 					cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1888 
1889 			if (ieee80211_is_data_qos(hdr->frame_control) ||
1890 			    ieee80211_is_qos_nullfunc(hdr->frame_control))
1891 				qoshdr = ieee80211_get_qos_ctl(hdr);
1892 
1893 			tids |= BIT(skb->priority);
1894 
1895 			__skb_queue_tail(&pending, skb);
1896 
1897 			/* end service period after last frame or add one */
1898 			if (!skb_queue_empty(&frames))
1899 				continue;
1900 
1901 			if (reason != IEEE80211_FRAME_RELEASE_UAPSD) {
1902 				/* for PS-Poll, there's only one frame */
1903 				info->flags |= IEEE80211_TX_STATUS_EOSP |
1904 					       IEEE80211_TX_CTL_REQ_TX_STATUS;
1905 				break;
1906 			}
1907 
1908 			/* For uAPSD, things are a bit more complicated. If the
1909 			 * last frame has a QoS header (i.e. is a QoS-data or
1910 			 * QoS-nulldata frame) then just set the EOSP bit there
1911 			 * and be done.
1912 			 * If the frame doesn't have a QoS header (which means
1913 			 * it should be a bufferable MMPDU) then we can't set
1914 			 * the EOSP bit in the QoS header; add a QoS-nulldata
1915 			 * frame to the list to send it after the MMPDU.
1916 			 *
1917 			 * Note that this code is only in the mac80211-release
1918 			 * code path, we assume that the driver will not buffer
1919 			 * anything but QoS-data frames, or if it does, will
1920 			 * create the QoS-nulldata frame by itself if needed.
1921 			 *
1922 			 * Cf. 802.11-2012 10.2.1.10 (c).
1923 			 */
1924 			if (qoshdr) {
1925 				*qoshdr |= IEEE80211_QOS_CTL_EOSP;
1926 
1927 				info->flags |= IEEE80211_TX_STATUS_EOSP |
1928 					       IEEE80211_TX_CTL_REQ_TX_STATUS;
1929 			} else {
1930 				/* The standard isn't completely clear on this
1931 				 * as it says the more-data bit should be set
1932 				 * if there are more BUs. The QoS-Null frame
1933 				 * we're about to send isn't buffered yet, we
1934 				 * only create it below, but let's pretend it
1935 				 * was buffered just in case some clients only
1936 				 * expect more-data=0 when eosp=1.
1937 				 */
1938 				hdr->frame_control |=
1939 					cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1940 				need_null = true;
1941 				num++;
1942 			}
1943 			break;
1944 		}
1945 
1946 		drv_allow_buffered_frames(local, sta, tids, num,
1947 					  reason, more_data);
1948 
1949 		ieee80211_add_pending_skbs(local, &pending);
1950 
1951 		if (need_null)
1952 			ieee80211_send_null_response(
1953 				sta, find_highest_prio_tid(tids),
1954 				reason, false, false);
1955 
1956 		sta_info_recalc_tim(sta);
1957 	} else {
1958 		int tid;
1959 
1960 		/*
1961 		 * We need to release a frame that is buffered somewhere in the
1962 		 * driver ... it'll have to handle that.
1963 		 * Note that the driver also has to check the number of frames
1964 		 * on the TIDs we're releasing from - if there are more than
1965 		 * n_frames it has to set the more-data bit (if we didn't ask
1966 		 * it to set it anyway due to other buffered frames); if there
1967 		 * are fewer than n_frames it has to make sure to adjust that
1968 		 * to allow the service period to end properly.
1969 		 */
1970 		drv_release_buffered_frames(local, sta, driver_release_tids,
1971 					    n_frames, reason, more_data);
1972 
1973 		/*
1974 		 * Note that we don't recalculate the TIM bit here as it would
1975 		 * most likely have no effect at all unless the driver told us
1976 		 * that the TID(s) became empty before returning here from the
1977 		 * release function.
1978 		 * Either way, however, when the driver tells us that the TID(s)
1979 		 * became empty or we find that a txq became empty, we'll do the
1980 		 * TIM recalculation.
1981 		 */
1982 
1983 		for (tid = 0; tid < ARRAY_SIZE(sta->sta.txq); tid++) {
1984 			if (!sta->sta.txq[tid] ||
1985 			    !(driver_release_tids & BIT(tid)) ||
1986 			    txq_has_queue(sta->sta.txq[tid]))
1987 				continue;
1988 
1989 			sta_info_recalc_tim(sta);
1990 			break;
1991 		}
1992 	}
1993 }
1994 
1995 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta)
1996 {
1997 	u8 ignore_for_response = sta->sta.uapsd_queues;
1998 
1999 	/*
2000 	 * If all ACs are delivery-enabled then we should reply
2001 	 * from any of them, if only some are enabled we reply
2002 	 * only from the non-enabled ones.
2003 	 */
2004 	if (ignore_for_response == BIT(IEEE80211_NUM_ACS) - 1)
2005 		ignore_for_response = 0;
2006 
2007 	ieee80211_sta_ps_deliver_response(sta, 1, ignore_for_response,
2008 					  IEEE80211_FRAME_RELEASE_PSPOLL);
2009 }
2010 
2011 void ieee80211_sta_ps_deliver_uapsd(struct sta_info *sta)
2012 {
2013 	int n_frames = sta->sta.max_sp;
2014 	u8 delivery_enabled = sta->sta.uapsd_queues;
2015 
2016 	/*
2017 	 * If we ever grow support for TSPEC this might happen if
2018 	 * the TSPEC update from hostapd comes in between a trigger
2019 	 * frame setting WLAN_STA_UAPSD in the RX path and this
2020 	 * actually getting called.
2021 	 */
2022 	if (!delivery_enabled)
2023 		return;
2024 
2025 	switch (sta->sta.max_sp) {
2026 	case 1:
2027 		n_frames = 2;
2028 		break;
2029 	case 2:
2030 		n_frames = 4;
2031 		break;
2032 	case 3:
2033 		n_frames = 6;
2034 		break;
2035 	case 0:
2036 		/* XXX: what is a good value? */
2037 		n_frames = 128;
2038 		break;
2039 	}
2040 
2041 	ieee80211_sta_ps_deliver_response(sta, n_frames, ~delivery_enabled,
2042 					  IEEE80211_FRAME_RELEASE_UAPSD);
2043 }
2044 
2045 void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
2046 			       struct ieee80211_sta *pubsta, bool block)
2047 {
2048 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2049 
2050 	trace_api_sta_block_awake(sta->local, pubsta, block);
2051 
2052 	if (block) {
2053 		set_sta_flag(sta, WLAN_STA_PS_DRIVER);
2054 		ieee80211_clear_fast_xmit(sta);
2055 		return;
2056 	}
2057 
2058 	if (!test_sta_flag(sta, WLAN_STA_PS_DRIVER))
2059 		return;
2060 
2061 	if (!test_sta_flag(sta, WLAN_STA_PS_STA)) {
2062 		set_sta_flag(sta, WLAN_STA_PS_DELIVER);
2063 		clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
2064 		ieee80211_queue_work(hw, &sta->drv_deliver_wk);
2065 	} else if (test_sta_flag(sta, WLAN_STA_PSPOLL) ||
2066 		   test_sta_flag(sta, WLAN_STA_UAPSD)) {
2067 		/* must be asleep in this case */
2068 		clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
2069 		ieee80211_queue_work(hw, &sta->drv_deliver_wk);
2070 	} else {
2071 		clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
2072 		ieee80211_check_fast_xmit(sta);
2073 	}
2074 }
2075 EXPORT_SYMBOL(ieee80211_sta_block_awake);
2076 
2077 void ieee80211_sta_eosp(struct ieee80211_sta *pubsta)
2078 {
2079 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2080 	struct ieee80211_local *local = sta->local;
2081 
2082 	trace_api_eosp(local, pubsta);
2083 
2084 	clear_sta_flag(sta, WLAN_STA_SP);
2085 }
2086 EXPORT_SYMBOL(ieee80211_sta_eosp);
2087 
2088 void ieee80211_send_eosp_nullfunc(struct ieee80211_sta *pubsta, int tid)
2089 {
2090 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2091 	enum ieee80211_frame_release_type reason;
2092 	bool more_data;
2093 
2094 	trace_api_send_eosp_nullfunc(sta->local, pubsta, tid);
2095 
2096 	reason = IEEE80211_FRAME_RELEASE_UAPSD;
2097 	more_data = ieee80211_sta_ps_more_data(sta, ~sta->sta.uapsd_queues,
2098 					       reason, 0);
2099 
2100 	ieee80211_send_null_response(sta, tid, reason, false, more_data);
2101 }
2102 EXPORT_SYMBOL(ieee80211_send_eosp_nullfunc);
2103 
2104 void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
2105 				u8 tid, bool buffered)
2106 {
2107 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2108 
2109 	if (WARN_ON(tid >= IEEE80211_NUM_TIDS))
2110 		return;
2111 
2112 	trace_api_sta_set_buffered(sta->local, pubsta, tid, buffered);
2113 
2114 	if (buffered)
2115 		set_bit(tid, &sta->driver_buffered_tids);
2116 	else
2117 		clear_bit(tid, &sta->driver_buffered_tids);
2118 
2119 	sta_info_recalc_tim(sta);
2120 }
2121 EXPORT_SYMBOL(ieee80211_sta_set_buffered);
2122 
2123 void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid,
2124 				    u32 tx_airtime, u32 rx_airtime)
2125 {
2126 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2127 	struct ieee80211_local *local = sta->sdata->local;
2128 	u8 ac = ieee80211_ac_from_tid(tid);
2129 	u32 airtime = 0;
2130 	u32 diff;
2131 
2132 	if (sta->local->airtime_flags & AIRTIME_USE_TX)
2133 		airtime += tx_airtime;
2134 	if (sta->local->airtime_flags & AIRTIME_USE_RX)
2135 		airtime += rx_airtime;
2136 
2137 	spin_lock_bh(&local->active_txq_lock[ac]);
2138 	sta->airtime[ac].tx_airtime += tx_airtime;
2139 	sta->airtime[ac].rx_airtime += rx_airtime;
2140 
2141 	diff = (u32)jiffies - sta->airtime[ac].last_active;
2142 	if (diff <= AIRTIME_ACTIVE_DURATION)
2143 		sta->airtime[ac].deficit -= airtime;
2144 
2145 	spin_unlock_bh(&local->active_txq_lock[ac]);
2146 }
2147 EXPORT_SYMBOL(ieee80211_sta_register_airtime);
2148 
2149 void __ieee80211_sta_recalc_aggregates(struct sta_info *sta, u16 active_links)
2150 {
2151 	bool first = true;
2152 	int link_id;
2153 
2154 	if (!sta->sta.valid_links || !sta->sta.mlo) {
2155 		sta->sta.cur = &sta->sta.deflink.agg;
2156 		return;
2157 	}
2158 
2159 	rcu_read_lock();
2160 	for (link_id = 0; link_id < ARRAY_SIZE((sta)->link); link_id++) {
2161 		struct ieee80211_link_sta *link_sta;
2162 		int i;
2163 
2164 		if (!(active_links & BIT(link_id)))
2165 			continue;
2166 
2167 		link_sta = rcu_dereference(sta->sta.link[link_id]);
2168 		if (!link_sta)
2169 			continue;
2170 
2171 		if (first) {
2172 			sta->cur = sta->sta.deflink.agg;
2173 			first = false;
2174 			continue;
2175 		}
2176 
2177 		sta->cur.max_amsdu_len =
2178 			min(sta->cur.max_amsdu_len,
2179 			    link_sta->agg.max_amsdu_len);
2180 		sta->cur.max_rc_amsdu_len =
2181 			min(sta->cur.max_rc_amsdu_len,
2182 			    link_sta->agg.max_rc_amsdu_len);
2183 
2184 		for (i = 0; i < ARRAY_SIZE(sta->cur.max_tid_amsdu_len); i++)
2185 			sta->cur.max_tid_amsdu_len[i] =
2186 				min(sta->cur.max_tid_amsdu_len[i],
2187 				    link_sta->agg.max_tid_amsdu_len[i]);
2188 	}
2189 	rcu_read_unlock();
2190 
2191 	sta->sta.cur = &sta->cur;
2192 }
2193 
2194 void ieee80211_sta_recalc_aggregates(struct ieee80211_sta *pubsta)
2195 {
2196 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2197 
2198 	__ieee80211_sta_recalc_aggregates(sta, sta->sdata->vif.active_links);
2199 }
2200 EXPORT_SYMBOL(ieee80211_sta_recalc_aggregates);
2201 
2202 void ieee80211_sta_update_pending_airtime(struct ieee80211_local *local,
2203 					  struct sta_info *sta, u8 ac,
2204 					  u16 tx_airtime, bool tx_completed)
2205 {
2206 	int tx_pending;
2207 
2208 	if (!wiphy_ext_feature_isset(local->hw.wiphy, NL80211_EXT_FEATURE_AQL))
2209 		return;
2210 
2211 	if (!tx_completed) {
2212 		if (sta)
2213 			atomic_add(tx_airtime,
2214 				   &sta->airtime[ac].aql_tx_pending);
2215 
2216 		atomic_add(tx_airtime, &local->aql_total_pending_airtime);
2217 		atomic_add(tx_airtime, &local->aql_ac_pending_airtime[ac]);
2218 		return;
2219 	}
2220 
2221 	if (sta) {
2222 		tx_pending = atomic_sub_return(tx_airtime,
2223 					       &sta->airtime[ac].aql_tx_pending);
2224 		if (tx_pending < 0)
2225 			atomic_cmpxchg(&sta->airtime[ac].aql_tx_pending,
2226 				       tx_pending, 0);
2227 	}
2228 
2229 	atomic_sub(tx_airtime, &local->aql_total_pending_airtime);
2230 	tx_pending = atomic_sub_return(tx_airtime,
2231 				       &local->aql_ac_pending_airtime[ac]);
2232 	if (WARN_ONCE(tx_pending < 0,
2233 		      "Device %s AC %d pending airtime underflow: %u, %u",
2234 		      wiphy_name(local->hw.wiphy), ac, tx_pending,
2235 		      tx_airtime)) {
2236 		atomic_cmpxchg(&local->aql_ac_pending_airtime[ac],
2237 			       tx_pending, 0);
2238 		atomic_sub(tx_pending, &local->aql_total_pending_airtime);
2239 	}
2240 }
2241 
2242 int sta_info_move_state(struct sta_info *sta,
2243 			enum ieee80211_sta_state new_state)
2244 {
2245 	might_sleep();
2246 
2247 	if (sta->sta_state == new_state)
2248 		return 0;
2249 
2250 	/* check allowed transitions first */
2251 
2252 	switch (new_state) {
2253 	case IEEE80211_STA_NONE:
2254 		if (sta->sta_state != IEEE80211_STA_AUTH)
2255 			return -EINVAL;
2256 		break;
2257 	case IEEE80211_STA_AUTH:
2258 		if (sta->sta_state != IEEE80211_STA_NONE &&
2259 		    sta->sta_state != IEEE80211_STA_ASSOC)
2260 			return -EINVAL;
2261 		break;
2262 	case IEEE80211_STA_ASSOC:
2263 		if (sta->sta_state != IEEE80211_STA_AUTH &&
2264 		    sta->sta_state != IEEE80211_STA_AUTHORIZED)
2265 			return -EINVAL;
2266 		break;
2267 	case IEEE80211_STA_AUTHORIZED:
2268 		if (sta->sta_state != IEEE80211_STA_ASSOC)
2269 			return -EINVAL;
2270 		break;
2271 	default:
2272 		WARN(1, "invalid state %d", new_state);
2273 		return -EINVAL;
2274 	}
2275 
2276 	sta_dbg(sta->sdata, "moving STA %pM to state %d\n",
2277 		sta->sta.addr, new_state);
2278 
2279 	/*
2280 	 * notify the driver before the actual changes so it can
2281 	 * fail the transition
2282 	 */
2283 	if (test_sta_flag(sta, WLAN_STA_INSERTED)) {
2284 		int err = drv_sta_state(sta->local, sta->sdata, sta,
2285 					sta->sta_state, new_state);
2286 		if (err)
2287 			return err;
2288 	}
2289 
2290 	/* reflect the change in all state variables */
2291 
2292 	switch (new_state) {
2293 	case IEEE80211_STA_NONE:
2294 		if (sta->sta_state == IEEE80211_STA_AUTH)
2295 			clear_bit(WLAN_STA_AUTH, &sta->_flags);
2296 		break;
2297 	case IEEE80211_STA_AUTH:
2298 		if (sta->sta_state == IEEE80211_STA_NONE) {
2299 			set_bit(WLAN_STA_AUTH, &sta->_flags);
2300 		} else if (sta->sta_state == IEEE80211_STA_ASSOC) {
2301 			clear_bit(WLAN_STA_ASSOC, &sta->_flags);
2302 			ieee80211_recalc_min_chandef(sta->sdata, -1);
2303 			if (!sta->sta.support_p2p_ps)
2304 				ieee80211_recalc_p2p_go_ps_allowed(sta->sdata);
2305 		}
2306 		break;
2307 	case IEEE80211_STA_ASSOC:
2308 		if (sta->sta_state == IEEE80211_STA_AUTH) {
2309 			set_bit(WLAN_STA_ASSOC, &sta->_flags);
2310 			sta->assoc_at = ktime_get_boottime_ns();
2311 			ieee80211_recalc_min_chandef(sta->sdata, -1);
2312 			if (!sta->sta.support_p2p_ps)
2313 				ieee80211_recalc_p2p_go_ps_allowed(sta->sdata);
2314 		} else if (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
2315 			ieee80211_vif_dec_num_mcast(sta->sdata);
2316 			clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
2317 			ieee80211_clear_fast_xmit(sta);
2318 			ieee80211_clear_fast_rx(sta);
2319 		}
2320 		break;
2321 	case IEEE80211_STA_AUTHORIZED:
2322 		if (sta->sta_state == IEEE80211_STA_ASSOC) {
2323 			ieee80211_vif_inc_num_mcast(sta->sdata);
2324 			set_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
2325 			ieee80211_check_fast_xmit(sta);
2326 			ieee80211_check_fast_rx(sta);
2327 		}
2328 		if (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
2329 		    sta->sdata->vif.type == NL80211_IFTYPE_AP)
2330 			cfg80211_send_layer2_update(sta->sdata->dev,
2331 						    sta->sta.addr);
2332 		break;
2333 	default:
2334 		break;
2335 	}
2336 
2337 	sta->sta_state = new_state;
2338 
2339 	return 0;
2340 }
2341 
2342 static struct ieee80211_sta_rx_stats *
2343 sta_get_last_rx_stats(struct sta_info *sta)
2344 {
2345 	struct ieee80211_sta_rx_stats *stats = &sta->deflink.rx_stats;
2346 	int cpu;
2347 
2348 	if (!sta->deflink.pcpu_rx_stats)
2349 		return stats;
2350 
2351 	for_each_possible_cpu(cpu) {
2352 		struct ieee80211_sta_rx_stats *cpustats;
2353 
2354 		cpustats = per_cpu_ptr(sta->deflink.pcpu_rx_stats, cpu);
2355 
2356 		if (time_after(cpustats->last_rx, stats->last_rx))
2357 			stats = cpustats;
2358 	}
2359 
2360 	return stats;
2361 }
2362 
2363 static void sta_stats_decode_rate(struct ieee80211_local *local, u32 rate,
2364 				  struct rate_info *rinfo)
2365 {
2366 	rinfo->bw = STA_STATS_GET(BW, rate);
2367 
2368 	switch (STA_STATS_GET(TYPE, rate)) {
2369 	case STA_STATS_RATE_TYPE_VHT:
2370 		rinfo->flags = RATE_INFO_FLAGS_VHT_MCS;
2371 		rinfo->mcs = STA_STATS_GET(VHT_MCS, rate);
2372 		rinfo->nss = STA_STATS_GET(VHT_NSS, rate);
2373 		if (STA_STATS_GET(SGI, rate))
2374 			rinfo->flags |= RATE_INFO_FLAGS_SHORT_GI;
2375 		break;
2376 	case STA_STATS_RATE_TYPE_HT:
2377 		rinfo->flags = RATE_INFO_FLAGS_MCS;
2378 		rinfo->mcs = STA_STATS_GET(HT_MCS, rate);
2379 		if (STA_STATS_GET(SGI, rate))
2380 			rinfo->flags |= RATE_INFO_FLAGS_SHORT_GI;
2381 		break;
2382 	case STA_STATS_RATE_TYPE_LEGACY: {
2383 		struct ieee80211_supported_band *sband;
2384 		u16 brate;
2385 		unsigned int shift;
2386 		int band = STA_STATS_GET(LEGACY_BAND, rate);
2387 		int rate_idx = STA_STATS_GET(LEGACY_IDX, rate);
2388 
2389 		sband = local->hw.wiphy->bands[band];
2390 
2391 		if (WARN_ON_ONCE(!sband->bitrates))
2392 			break;
2393 
2394 		brate = sband->bitrates[rate_idx].bitrate;
2395 		if (rinfo->bw == RATE_INFO_BW_5)
2396 			shift = 2;
2397 		else if (rinfo->bw == RATE_INFO_BW_10)
2398 			shift = 1;
2399 		else
2400 			shift = 0;
2401 		rinfo->legacy = DIV_ROUND_UP(brate, 1 << shift);
2402 		break;
2403 		}
2404 	case STA_STATS_RATE_TYPE_HE:
2405 		rinfo->flags = RATE_INFO_FLAGS_HE_MCS;
2406 		rinfo->mcs = STA_STATS_GET(HE_MCS, rate);
2407 		rinfo->nss = STA_STATS_GET(HE_NSS, rate);
2408 		rinfo->he_gi = STA_STATS_GET(HE_GI, rate);
2409 		rinfo->he_ru_alloc = STA_STATS_GET(HE_RU, rate);
2410 		rinfo->he_dcm = STA_STATS_GET(HE_DCM, rate);
2411 		break;
2412 	case STA_STATS_RATE_TYPE_EHT:
2413 		rinfo->flags = RATE_INFO_FLAGS_EHT_MCS;
2414 		rinfo->mcs = STA_STATS_GET(EHT_MCS, rate);
2415 		rinfo->nss = STA_STATS_GET(EHT_NSS, rate);
2416 		rinfo->eht_gi = STA_STATS_GET(EHT_GI, rate);
2417 		rinfo->eht_ru_alloc = STA_STATS_GET(EHT_RU, rate);
2418 		break;
2419 	}
2420 }
2421 
2422 static int sta_set_rate_info_rx(struct sta_info *sta, struct rate_info *rinfo)
2423 {
2424 	u32 rate = READ_ONCE(sta_get_last_rx_stats(sta)->last_rate);
2425 
2426 	if (rate == STA_STATS_RATE_INVALID)
2427 		return -EINVAL;
2428 
2429 	sta_stats_decode_rate(sta->local, rate, rinfo);
2430 	return 0;
2431 }
2432 
2433 static inline u64 sta_get_tidstats_msdu(struct ieee80211_sta_rx_stats *rxstats,
2434 					int tid)
2435 {
2436 	unsigned int start;
2437 	u64 value;
2438 
2439 	do {
2440 		start = u64_stats_fetch_begin(&rxstats->syncp);
2441 		value = rxstats->msdu[tid];
2442 	} while (u64_stats_fetch_retry(&rxstats->syncp, start));
2443 
2444 	return value;
2445 }
2446 
2447 static void sta_set_tidstats(struct sta_info *sta,
2448 			     struct cfg80211_tid_stats *tidstats,
2449 			     int tid)
2450 {
2451 	struct ieee80211_local *local = sta->local;
2452 	int cpu;
2453 
2454 	if (!(tidstats->filled & BIT(NL80211_TID_STATS_RX_MSDU))) {
2455 		tidstats->rx_msdu += sta_get_tidstats_msdu(&sta->deflink.rx_stats,
2456 							   tid);
2457 
2458 		if (sta->deflink.pcpu_rx_stats) {
2459 			for_each_possible_cpu(cpu) {
2460 				struct ieee80211_sta_rx_stats *cpurxs;
2461 
2462 				cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats,
2463 						     cpu);
2464 				tidstats->rx_msdu +=
2465 					sta_get_tidstats_msdu(cpurxs, tid);
2466 			}
2467 		}
2468 
2469 		tidstats->filled |= BIT(NL80211_TID_STATS_RX_MSDU);
2470 	}
2471 
2472 	if (!(tidstats->filled & BIT(NL80211_TID_STATS_TX_MSDU))) {
2473 		tidstats->filled |= BIT(NL80211_TID_STATS_TX_MSDU);
2474 		tidstats->tx_msdu = sta->deflink.tx_stats.msdu[tid];
2475 	}
2476 
2477 	if (!(tidstats->filled & BIT(NL80211_TID_STATS_TX_MSDU_RETRIES)) &&
2478 	    ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
2479 		tidstats->filled |= BIT(NL80211_TID_STATS_TX_MSDU_RETRIES);
2480 		tidstats->tx_msdu_retries = sta->deflink.status_stats.msdu_retries[tid];
2481 	}
2482 
2483 	if (!(tidstats->filled & BIT(NL80211_TID_STATS_TX_MSDU_FAILED)) &&
2484 	    ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
2485 		tidstats->filled |= BIT(NL80211_TID_STATS_TX_MSDU_FAILED);
2486 		tidstats->tx_msdu_failed = sta->deflink.status_stats.msdu_failed[tid];
2487 	}
2488 
2489 	if (tid < IEEE80211_NUM_TIDS) {
2490 		spin_lock_bh(&local->fq.lock);
2491 		rcu_read_lock();
2492 
2493 		tidstats->filled |= BIT(NL80211_TID_STATS_TXQ_STATS);
2494 		ieee80211_fill_txq_stats(&tidstats->txq_stats,
2495 					 to_txq_info(sta->sta.txq[tid]));
2496 
2497 		rcu_read_unlock();
2498 		spin_unlock_bh(&local->fq.lock);
2499 	}
2500 }
2501 
2502 static inline u64 sta_get_stats_bytes(struct ieee80211_sta_rx_stats *rxstats)
2503 {
2504 	unsigned int start;
2505 	u64 value;
2506 
2507 	do {
2508 		start = u64_stats_fetch_begin(&rxstats->syncp);
2509 		value = rxstats->bytes;
2510 	} while (u64_stats_fetch_retry(&rxstats->syncp, start));
2511 
2512 	return value;
2513 }
2514 
2515 void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
2516 		   bool tidstats)
2517 {
2518 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2519 	struct ieee80211_local *local = sdata->local;
2520 	u32 thr = 0;
2521 	int i, ac, cpu;
2522 	struct ieee80211_sta_rx_stats *last_rxstats;
2523 
2524 	last_rxstats = sta_get_last_rx_stats(sta);
2525 
2526 	sinfo->generation = sdata->local->sta_generation;
2527 
2528 	/* do before driver, so beacon filtering drivers have a
2529 	 * chance to e.g. just add the number of filtered beacons
2530 	 * (or just modify the value entirely, of course)
2531 	 */
2532 	if (sdata->vif.type == NL80211_IFTYPE_STATION)
2533 		sinfo->rx_beacon = sdata->deflink.u.mgd.count_beacon_signal;
2534 
2535 	drv_sta_statistics(local, sdata, &sta->sta, sinfo);
2536 	sinfo->filled |= BIT_ULL(NL80211_STA_INFO_INACTIVE_TIME) |
2537 			 BIT_ULL(NL80211_STA_INFO_STA_FLAGS) |
2538 			 BIT_ULL(NL80211_STA_INFO_BSS_PARAM) |
2539 			 BIT_ULL(NL80211_STA_INFO_CONNECTED_TIME) |
2540 			 BIT_ULL(NL80211_STA_INFO_ASSOC_AT_BOOTTIME) |
2541 			 BIT_ULL(NL80211_STA_INFO_RX_DROP_MISC);
2542 
2543 	if (sdata->vif.type == NL80211_IFTYPE_STATION) {
2544 		sinfo->beacon_loss_count =
2545 			sdata->deflink.u.mgd.beacon_loss_count;
2546 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_BEACON_LOSS);
2547 	}
2548 
2549 	sinfo->connected_time = ktime_get_seconds() - sta->last_connected;
2550 	sinfo->assoc_at = sta->assoc_at;
2551 	sinfo->inactive_time =
2552 		jiffies_to_msecs(jiffies - ieee80211_sta_last_active(sta));
2553 
2554 	if (!(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_TX_BYTES64) |
2555 			       BIT_ULL(NL80211_STA_INFO_TX_BYTES)))) {
2556 		sinfo->tx_bytes = 0;
2557 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
2558 			sinfo->tx_bytes += sta->deflink.tx_stats.bytes[ac];
2559 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BYTES64);
2560 	}
2561 
2562 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_PACKETS))) {
2563 		sinfo->tx_packets = 0;
2564 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
2565 			sinfo->tx_packets += sta->deflink.tx_stats.packets[ac];
2566 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_PACKETS);
2567 	}
2568 
2569 	if (!(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_RX_BYTES64) |
2570 			       BIT_ULL(NL80211_STA_INFO_RX_BYTES)))) {
2571 		sinfo->rx_bytes += sta_get_stats_bytes(&sta->deflink.rx_stats);
2572 
2573 		if (sta->deflink.pcpu_rx_stats) {
2574 			for_each_possible_cpu(cpu) {
2575 				struct ieee80211_sta_rx_stats *cpurxs;
2576 
2577 				cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats,
2578 						     cpu);
2579 				sinfo->rx_bytes += sta_get_stats_bytes(cpurxs);
2580 			}
2581 		}
2582 
2583 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_BYTES64);
2584 	}
2585 
2586 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_PACKETS))) {
2587 		sinfo->rx_packets = sta->deflink.rx_stats.packets;
2588 		if (sta->deflink.pcpu_rx_stats) {
2589 			for_each_possible_cpu(cpu) {
2590 				struct ieee80211_sta_rx_stats *cpurxs;
2591 
2592 				cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats,
2593 						     cpu);
2594 				sinfo->rx_packets += cpurxs->packets;
2595 			}
2596 		}
2597 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_PACKETS);
2598 	}
2599 
2600 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_RETRIES))) {
2601 		sinfo->tx_retries = sta->deflink.status_stats.retry_count;
2602 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_RETRIES);
2603 	}
2604 
2605 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_FAILED))) {
2606 		sinfo->tx_failed = sta->deflink.status_stats.retry_failed;
2607 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_FAILED);
2608 	}
2609 
2610 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_DURATION))) {
2611 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
2612 			sinfo->rx_duration += sta->airtime[ac].rx_airtime;
2613 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_DURATION);
2614 	}
2615 
2616 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_DURATION))) {
2617 		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
2618 			sinfo->tx_duration += sta->airtime[ac].tx_airtime;
2619 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_DURATION);
2620 	}
2621 
2622 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT))) {
2623 		sinfo->airtime_weight = sta->airtime_weight;
2624 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT);
2625 	}
2626 
2627 	sinfo->rx_dropped_misc = sta->deflink.rx_stats.dropped;
2628 	if (sta->deflink.pcpu_rx_stats) {
2629 		for_each_possible_cpu(cpu) {
2630 			struct ieee80211_sta_rx_stats *cpurxs;
2631 
2632 			cpurxs = per_cpu_ptr(sta->deflink.pcpu_rx_stats, cpu);
2633 			sinfo->rx_dropped_misc += cpurxs->dropped;
2634 		}
2635 	}
2636 
2637 	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
2638 	    !(sdata->vif.driver_flags & IEEE80211_VIF_BEACON_FILTER)) {
2639 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_BEACON_RX) |
2640 				 BIT_ULL(NL80211_STA_INFO_BEACON_SIGNAL_AVG);
2641 		sinfo->rx_beacon_signal_avg = ieee80211_ave_rssi(&sdata->vif);
2642 	}
2643 
2644 	if (ieee80211_hw_check(&sta->local->hw, SIGNAL_DBM) ||
2645 	    ieee80211_hw_check(&sta->local->hw, SIGNAL_UNSPEC)) {
2646 		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_SIGNAL))) {
2647 			sinfo->signal = (s8)last_rxstats->last_signal;
2648 			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL);
2649 		}
2650 
2651 		if (!sta->deflink.pcpu_rx_stats &&
2652 		    !(sinfo->filled & BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG))) {
2653 			sinfo->signal_avg =
2654 				-ewma_signal_read(&sta->deflink.rx_stats_avg.signal);
2655 			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG);
2656 		}
2657 	}
2658 
2659 	/* for the average - if pcpu_rx_stats isn't set - rxstats must point to
2660 	 * the sta->rx_stats struct, so the check here is fine with and without
2661 	 * pcpu statistics
2662 	 */
2663 	if (last_rxstats->chains &&
2664 	    !(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL) |
2665 			       BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL_AVG)))) {
2666 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL);
2667 		if (!sta->deflink.pcpu_rx_stats)
2668 			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL_AVG);
2669 
2670 		sinfo->chains = last_rxstats->chains;
2671 
2672 		for (i = 0; i < ARRAY_SIZE(sinfo->chain_signal); i++) {
2673 			sinfo->chain_signal[i] =
2674 				last_rxstats->chain_signal_last[i];
2675 			sinfo->chain_signal_avg[i] =
2676 				-ewma_signal_read(&sta->deflink.rx_stats_avg.chain_signal[i]);
2677 		}
2678 	}
2679 
2680 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_BITRATE)) &&
2681 	    !sta->sta.valid_links) {
2682 		sta_set_rate_info_tx(sta, &sta->deflink.tx_stats.last_rate,
2683 				     &sinfo->txrate);
2684 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BITRATE);
2685 	}
2686 
2687 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_BITRATE)) &&
2688 	    !sta->sta.valid_links) {
2689 		if (sta_set_rate_info_rx(sta, &sinfo->rxrate) == 0)
2690 			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_BITRATE);
2691 	}
2692 
2693 	if (tidstats && !cfg80211_sinfo_alloc_tid_stats(sinfo, GFP_KERNEL)) {
2694 		for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++)
2695 			sta_set_tidstats(sta, &sinfo->pertid[i], i);
2696 	}
2697 
2698 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
2699 #ifdef CONFIG_MAC80211_MESH
2700 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_LLID) |
2701 				 BIT_ULL(NL80211_STA_INFO_PLID) |
2702 				 BIT_ULL(NL80211_STA_INFO_PLINK_STATE) |
2703 				 BIT_ULL(NL80211_STA_INFO_LOCAL_PM) |
2704 				 BIT_ULL(NL80211_STA_INFO_PEER_PM) |
2705 				 BIT_ULL(NL80211_STA_INFO_NONPEER_PM) |
2706 				 BIT_ULL(NL80211_STA_INFO_CONNECTED_TO_GATE) |
2707 				 BIT_ULL(NL80211_STA_INFO_CONNECTED_TO_AS);
2708 
2709 		sinfo->llid = sta->mesh->llid;
2710 		sinfo->plid = sta->mesh->plid;
2711 		sinfo->plink_state = sta->mesh->plink_state;
2712 		if (test_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN)) {
2713 			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_T_OFFSET);
2714 			sinfo->t_offset = sta->mesh->t_offset;
2715 		}
2716 		sinfo->local_pm = sta->mesh->local_pm;
2717 		sinfo->peer_pm = sta->mesh->peer_pm;
2718 		sinfo->nonpeer_pm = sta->mesh->nonpeer_pm;
2719 		sinfo->connected_to_gate = sta->mesh->connected_to_gate;
2720 		sinfo->connected_to_as = sta->mesh->connected_to_as;
2721 #endif
2722 	}
2723 
2724 	sinfo->bss_param.flags = 0;
2725 	if (sdata->vif.bss_conf.use_cts_prot)
2726 		sinfo->bss_param.flags |= BSS_PARAM_FLAGS_CTS_PROT;
2727 	if (sdata->vif.bss_conf.use_short_preamble)
2728 		sinfo->bss_param.flags |= BSS_PARAM_FLAGS_SHORT_PREAMBLE;
2729 	if (sdata->vif.bss_conf.use_short_slot)
2730 		sinfo->bss_param.flags |= BSS_PARAM_FLAGS_SHORT_SLOT_TIME;
2731 	sinfo->bss_param.dtim_period = sdata->vif.bss_conf.dtim_period;
2732 	sinfo->bss_param.beacon_interval = sdata->vif.bss_conf.beacon_int;
2733 
2734 	sinfo->sta_flags.set = 0;
2735 	sinfo->sta_flags.mask = BIT(NL80211_STA_FLAG_AUTHORIZED) |
2736 				BIT(NL80211_STA_FLAG_SHORT_PREAMBLE) |
2737 				BIT(NL80211_STA_FLAG_WME) |
2738 				BIT(NL80211_STA_FLAG_MFP) |
2739 				BIT(NL80211_STA_FLAG_AUTHENTICATED) |
2740 				BIT(NL80211_STA_FLAG_ASSOCIATED) |
2741 				BIT(NL80211_STA_FLAG_TDLS_PEER);
2742 	if (test_sta_flag(sta, WLAN_STA_AUTHORIZED))
2743 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_AUTHORIZED);
2744 	if (test_sta_flag(sta, WLAN_STA_SHORT_PREAMBLE))
2745 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_SHORT_PREAMBLE);
2746 	if (sta->sta.wme)
2747 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_WME);
2748 	if (test_sta_flag(sta, WLAN_STA_MFP))
2749 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_MFP);
2750 	if (test_sta_flag(sta, WLAN_STA_AUTH))
2751 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_AUTHENTICATED);
2752 	if (test_sta_flag(sta, WLAN_STA_ASSOC))
2753 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_ASSOCIATED);
2754 	if (test_sta_flag(sta, WLAN_STA_TDLS_PEER))
2755 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
2756 
2757 	thr = sta_get_expected_throughput(sta);
2758 
2759 	if (thr != 0) {
2760 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_EXPECTED_THROUGHPUT);
2761 		sinfo->expected_throughput = thr;
2762 	}
2763 
2764 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL)) &&
2765 	    sta->deflink.status_stats.ack_signal_filled) {
2766 		sinfo->ack_signal = sta->deflink.status_stats.last_ack_signal;
2767 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL);
2768 	}
2769 
2770 	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL_AVG)) &&
2771 	    sta->deflink.status_stats.ack_signal_filled) {
2772 		sinfo->avg_ack_signal =
2773 			-(s8)ewma_avg_signal_read(
2774 				&sta->deflink.status_stats.avg_ack_signal);
2775 		sinfo->filled |=
2776 			BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL_AVG);
2777 	}
2778 
2779 	if (ieee80211_vif_is_mesh(&sdata->vif)) {
2780 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_AIRTIME_LINK_METRIC);
2781 		sinfo->airtime_link_metric =
2782 			airtime_link_metric_get(local, sta);
2783 	}
2784 }
2785 
2786 u32 sta_get_expected_throughput(struct sta_info *sta)
2787 {
2788 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2789 	struct ieee80211_local *local = sdata->local;
2790 	struct rate_control_ref *ref = NULL;
2791 	u32 thr = 0;
2792 
2793 	if (test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
2794 		ref = local->rate_ctrl;
2795 
2796 	/* check if the driver has a SW RC implementation */
2797 	if (ref && ref->ops->get_expected_throughput)
2798 		thr = ref->ops->get_expected_throughput(sta->rate_ctrl_priv);
2799 	else
2800 		thr = drv_get_expected_throughput(local, sta);
2801 
2802 	return thr;
2803 }
2804 
2805 unsigned long ieee80211_sta_last_active(struct sta_info *sta)
2806 {
2807 	struct ieee80211_sta_rx_stats *stats = sta_get_last_rx_stats(sta);
2808 
2809 	if (!sta->deflink.status_stats.last_ack ||
2810 	    time_after(stats->last_rx, sta->deflink.status_stats.last_ack))
2811 		return stats->last_rx;
2812 	return sta->deflink.status_stats.last_ack;
2813 }
2814 
2815 static void sta_update_codel_params(struct sta_info *sta, u32 thr)
2816 {
2817 	if (thr && thr < STA_SLOW_THRESHOLD * sta->local->num_sta) {
2818 		sta->cparams.target = MS2TIME(50);
2819 		sta->cparams.interval = MS2TIME(300);
2820 		sta->cparams.ecn = false;
2821 	} else {
2822 		sta->cparams.target = MS2TIME(20);
2823 		sta->cparams.interval = MS2TIME(100);
2824 		sta->cparams.ecn = true;
2825 	}
2826 }
2827 
2828 void ieee80211_sta_set_expected_throughput(struct ieee80211_sta *pubsta,
2829 					   u32 thr)
2830 {
2831 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2832 
2833 	sta_update_codel_params(sta, thr);
2834 }
2835 
2836 int ieee80211_sta_allocate_link(struct sta_info *sta, unsigned int link_id)
2837 {
2838 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2839 	struct sta_link_alloc *alloc;
2840 	int ret;
2841 
2842 	lockdep_assert_held(&sdata->local->sta_mtx);
2843 
2844 	/* must represent an MLD from the start */
2845 	if (WARN_ON(!sta->sta.valid_links))
2846 		return -EINVAL;
2847 
2848 	if (WARN_ON(sta->sta.valid_links & BIT(link_id) ||
2849 		    sta->link[link_id]))
2850 		return -EBUSY;
2851 
2852 	alloc = kzalloc(sizeof(*alloc), GFP_KERNEL);
2853 	if (!alloc)
2854 		return -ENOMEM;
2855 
2856 	ret = sta_info_alloc_link(sdata->local, &alloc->info, GFP_KERNEL);
2857 	if (ret) {
2858 		kfree(alloc);
2859 		return ret;
2860 	}
2861 
2862 	sta_info_add_link(sta, link_id, &alloc->info, &alloc->sta);
2863 
2864 	ieee80211_link_sta_debugfs_add(&alloc->info);
2865 
2866 	return 0;
2867 }
2868 
2869 void ieee80211_sta_free_link(struct sta_info *sta, unsigned int link_id)
2870 {
2871 	lockdep_assert_held(&sta->sdata->local->sta_mtx);
2872 
2873 	sta_remove_link(sta, link_id, false);
2874 }
2875 
2876 int ieee80211_sta_activate_link(struct sta_info *sta, unsigned int link_id)
2877 {
2878 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2879 	struct link_sta_info *link_sta;
2880 	u16 old_links = sta->sta.valid_links;
2881 	u16 new_links = old_links | BIT(link_id);
2882 	int ret;
2883 
2884 	link_sta = rcu_dereference_protected(sta->link[link_id],
2885 					     lockdep_is_held(&sdata->local->sta_mtx));
2886 
2887 	if (WARN_ON(old_links == new_links || !link_sta))
2888 		return -EINVAL;
2889 
2890 	rcu_read_lock();
2891 	if (link_sta_info_hash_lookup(sdata->local, link_sta->addr)) {
2892 		rcu_read_unlock();
2893 		return -EALREADY;
2894 	}
2895 	/* we only modify under the mutex so this is fine */
2896 	rcu_read_unlock();
2897 
2898 	sta->sta.valid_links = new_links;
2899 
2900 	if (!test_sta_flag(sta, WLAN_STA_INSERTED))
2901 		goto hash;
2902 
2903 	/* Ensure the values are updated for the driver,
2904 	 * redone by sta_remove_link on failure.
2905 	 */
2906 	ieee80211_sta_recalc_aggregates(&sta->sta);
2907 
2908 	ret = drv_change_sta_links(sdata->local, sdata, &sta->sta,
2909 				   old_links, new_links);
2910 	if (ret) {
2911 		sta->sta.valid_links = old_links;
2912 		sta_remove_link(sta, link_id, false);
2913 		return ret;
2914 	}
2915 
2916 hash:
2917 	ret = link_sta_info_hash_add(sdata->local, link_sta);
2918 	WARN_ON(ret);
2919 	return 0;
2920 }
2921 
2922 void ieee80211_sta_remove_link(struct sta_info *sta, unsigned int link_id)
2923 {
2924 	struct ieee80211_sub_if_data *sdata = sta->sdata;
2925 	u16 old_links = sta->sta.valid_links;
2926 
2927 	lockdep_assert_held(&sdata->local->sta_mtx);
2928 
2929 	sta->sta.valid_links &= ~BIT(link_id);
2930 
2931 	if (test_sta_flag(sta, WLAN_STA_INSERTED))
2932 		drv_change_sta_links(sdata->local, sdata, &sta->sta,
2933 				     old_links, sta->sta.valid_links);
2934 
2935 	sta_remove_link(sta, link_id, true);
2936 }
2937 
2938 void ieee80211_sta_set_max_amsdu_subframes(struct sta_info *sta,
2939 					   const u8 *ext_capab,
2940 					   unsigned int ext_capab_len)
2941 {
2942 	u8 val;
2943 
2944 	sta->sta.max_amsdu_subframes = 0;
2945 
2946 	if (ext_capab_len < 8)
2947 		return;
2948 
2949 	/* The sender might not have sent the last bit, consider it to be 0 */
2950 	val = u8_get_bits(ext_capab[7], WLAN_EXT_CAPA8_MAX_MSDU_IN_AMSDU_LSB);
2951 
2952 	/* we did get all the bits, take the MSB as well */
2953 	if (ext_capab_len >= 9)
2954 		val |= u8_get_bits(ext_capab[8],
2955 				   WLAN_EXT_CAPA9_MAX_MSDU_IN_AMSDU_MSB) << 1;
2956 
2957 	if (val)
2958 		sta->sta.max_amsdu_subframes = 4 << val;
2959 }
2960 
2961 #ifdef CONFIG_LOCKDEP
2962 bool lockdep_sta_mutex_held(struct ieee80211_sta *pubsta)
2963 {
2964 	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
2965 
2966 	return lockdep_is_held(&sta->local->sta_mtx);
2967 }
2968 EXPORT_SYMBOL(lockdep_sta_mutex_held);
2969 #endif
2970