summaryrefslogtreecommitdiff
path: root/net/mac80211/link.c
blob: e82db88a47f8f4e05c14a1849a946cc1ea79e94e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
// SPDX-License-Identifier: GPL-2.0-only
/*
 * MLO link handling
 *
 * Copyright (C) 2022 Intel Corporation
 */
#include <linux/slab.h>
#include <linux/kernel.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "key.h"
#include "debugfs_netdev.h"

void ieee80211_link_setup(struct ieee80211_link_data *link)
{
	if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
		ieee80211_mgd_setup_link(link);
}

void ieee80211_link_init(struct ieee80211_sub_if_data *sdata,
			 int link_id,
			 struct ieee80211_link_data *link,
			 struct ieee80211_bss_conf *link_conf)
{
	bool deflink = link_id < 0;

	if (link_id < 0)
		link_id = 0;

	rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf);
	rcu_assign_pointer(sdata->link[link_id], link);

	link->sdata = sdata;
	link->link_id = link_id;
	link->conf = link_conf;
	link_conf->link_id = link_id;
	link_conf->vif = &sdata->vif;

	INIT_WORK(&link->csa_finalize_work,
		  ieee80211_csa_finalize_work);
	INIT_WORK(&link->color_change_finalize_work,
		  ieee80211_color_change_finalize_work);
	INIT_DELAYED_WORK(&link->color_collision_detect_work,
			  ieee80211_color_collision_detection_work);
	INIT_LIST_HEAD(&link->assigned_chanctx_list);
	INIT_LIST_HEAD(&link->reserved_chanctx_list);
	INIT_DELAYED_WORK(&link->dfs_cac_timer_work,
			  ieee80211_dfs_cac_timer_work);

	if (!deflink) {
		switch (sdata->vif.type) {
		case NL80211_IFTYPE_AP:
			ether_addr_copy(link_conf->addr,
					sdata->wdev.links[link_id].addr);
			link_conf->bssid = link_conf->addr;
			WARN_ON(!(sdata->wdev.valid_links & BIT(link_id)));
			break;
		case NL80211_IFTYPE_STATION:
			/* station sets the bssid in ieee80211_mgd_setup_link */
			break;
		default:
			WARN_ON(1);
		}

		ieee80211_link_debugfs_add(link);
	}
}

void ieee80211_link_stop(struct ieee80211_link_data *link)
{
	if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
		ieee80211_mgd_stop_link(link);

	cancel_delayed_work_sync(&link->color_collision_detect_work);
	ieee80211_link_release_channel(link);
}

struct link_container {
	struct ieee80211_link_data data;
	struct ieee80211_bss_conf conf;
};

static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata,
				      struct link_container **links, u16 mask)
{
	struct ieee80211_link_data *link;
	LIST_HEAD(keys);
	unsigned int link_id;

	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
		if (!(mask & BIT(link_id)))
			continue;
		link = &links[link_id]->data;
		if (link_id == 0 && !link)
			link = &sdata->deflink;
		if (WARN_ON(!link))
			continue;
		ieee80211_remove_link_keys(link, &keys);
		ieee80211_link_debugfs_remove(link);
		ieee80211_link_stop(link);
	}

	synchronize_rcu();

	ieee80211_free_key_list(sdata->local, &keys);
}

static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata,
				 struct link_container **links)
{
	unsigned int link_id;

	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++)
		kfree(links[link_id]);
}

static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata)
{
	unsigned int i, j;

	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
		struct ieee80211_link_data *link1;

		link1 = sdata_dereference(sdata->link[i], sdata);
		if (!link1)
			continue;
		for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) {
			struct ieee80211_link_data *link2;

			link2 = sdata_dereference(sdata->link[j], sdata);
			if (!link2)
				continue;

			if (ether_addr_equal(link1->conf->addr,
					     link2->conf->addr))
				return -EALREADY;
		}
	}

	return 0;
}

static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata,
					    u16 links)
{
	sdata->vif.valid_links = links;

	if (!links) {
		sdata->vif.active_links = 0;
		return;
	}

	switch (sdata->vif.type) {
	case NL80211_IFTYPE_AP:
		/* in an AP all links are always active */
		sdata->vif.active_links = links;
		break;
	case NL80211_IFTYPE_STATION:
		if (sdata->vif.active_links)
			break;
		WARN_ON(hweight16(links) > 1);
		sdata->vif.active_links = links;
		break;
	default:
		WARN_ON(1);
	}
}

static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata,
				      struct link_container **to_free,
				      u16 new_links)
{
	u16 old_links = sdata->vif.valid_links;
	u16 old_active = sdata->vif.active_links;
	unsigned long add = new_links & ~old_links;
	unsigned long rem = old_links & ~new_links;
	unsigned int link_id;
	int ret;
	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, *link;
	struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS];
	struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS];
	bool use_deflink = old_links == 0; /* set for error case */

	sdata_assert_lock(sdata);

	memset(to_free, 0, sizeof(links));

	if (old_links == new_links)
		return 0;

	/* if there were no old links, need to clear the pointers to deflink */
	if (!old_links)
		rem |= BIT(0);

	/* allocate new link structures first */
	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
		link = kzalloc(sizeof(*link), GFP_KERNEL);
		if (!link) {
			ret = -ENOMEM;
			goto free;
		}
		links[link_id] = link;
	}

	/* keep track of the old pointers for the driver */
	BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf));
	memcpy(old, sdata->vif.link_conf, sizeof(old));
	/* and for us in error cases */
	BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link));
	memcpy(old_data, sdata->link, sizeof(old_data));

	/* grab old links to free later */
	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
		if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) {
			/*
			 * we must have allocated the data through this path so
			 * we know we can free both at the same time
			 */
			to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]),
							typeof(*links[link_id]),
							data);
		}

		RCU_INIT_POINTER(sdata->link[link_id], NULL);
		RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL);
	}

	/* link them into data structures */
	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
		WARN_ON(!use_deflink &&
			rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink);

		link = links[link_id];
		ieee80211_link_init(sdata, link_id, &link->data, &link->conf);
		ieee80211_link_setup(&link->data);
	}

	if (new_links == 0)
		ieee80211_link_init(sdata, -1, &sdata->deflink,
				    &sdata->vif.bss_conf);

	ret = ieee80211_check_dup_link_addrs(sdata);
	if (!ret) {
		/* for keys we will not be able to undo this */
		ieee80211_tear_down_links(sdata, to_free, rem);

		ieee80211_set_vif_links_bitmaps(sdata, new_links);

		/* tell the driver */
		ret = drv_change_vif_links(sdata->local, sdata,
					   old_links & old_active,
					   new_links & sdata->vif.active_links,
					   old);
	}

	if (ret) {
		/* restore config */
		memcpy(sdata->link, old_data, sizeof(old_data));
		memcpy(sdata->vif.link_conf, old, sizeof(old));
		ieee80211_set_vif_links_bitmaps(sdata, old_links);
		/* and free (only) the newly allocated links */
		memset(to_free, 0, sizeof(links));
		goto free;
	}

	/* use deflink/bss_conf again if and only if there are no more links */
	use_deflink = new_links == 0;

	goto deinit;
free:
	/* if we failed during allocation, only free all */
	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
		kfree(links[link_id]);
		links[link_id] = NULL;
	}
deinit:
	if (use_deflink)
		ieee80211_link_init(sdata, -1, &sdata->deflink,
				    &sdata->vif.bss_conf);
	return ret;
}

int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata,
			    u16 new_links)
{
	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
	int ret;

	ret = ieee80211_vif_update_links(sdata, links, new_links);
	ieee80211_free_links(sdata, links);

	return ret;
}

void ieee80211_vif_clear_links(struct ieee80211_sub_if_data *sdata)
{
	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];

	/*
	 * The locking here is different because when we free links
	 * in the station case we need to be able to cancel_work_sync()
	 * something that also takes the lock.
	 */

	sdata_lock(sdata);
	ieee80211_vif_update_links(sdata, links, 0);
	sdata_unlock(sdata);

	ieee80211_free_links(sdata, links);
}

static int _ieee80211_set_active_links(struct ieee80211_sub_if_data *sdata,
				       u16 active_links)
{
	struct ieee80211_bss_conf *link_confs[IEEE80211_MLD_MAX_NUM_LINKS];
	struct ieee80211_local *local = sdata->local;
	u16 old_active = sdata->vif.active_links;
	unsigned long rem = old_active & ~active_links;
	unsigned long add = active_links & ~old_active;
	struct sta_info *sta;
	unsigned int link_id;
	int ret, i;

	if (!ieee80211_sdata_running(sdata))
		return -ENETDOWN;

	if (sdata->vif.type != NL80211_IFTYPE_STATION)
		return -EINVAL;

	/* cannot activate links that don't exist */
	if (active_links & ~sdata->vif.valid_links)
		return -EINVAL;

	/* nothing to do */
	if (old_active == active_links)
		return 0;

	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++)
		link_confs[i] = sdata_dereference(sdata->vif.link_conf[i],
						  sdata);

	if (add) {
		sdata->vif.active_links |= active_links;
		ret = drv_change_vif_links(local, sdata,
					   old_active,
					   sdata->vif.active_links,
					   link_confs);
		if (ret) {
			sdata->vif.active_links = old_active;
			return ret;
		}
	}

	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
		struct ieee80211_link_data *link;

		link = sdata_dereference(sdata->link[link_id], sdata);

		/* FIXME: kill TDLS connections on the link */

		ieee80211_link_release_channel(link);
	}

	list_for_each_entry(sta, &local->sta_list, list) {
		if (sdata != sta->sdata)
			continue;

		/* this is very temporary, but do it anyway */
		__ieee80211_sta_recalc_aggregates(sta,
						  old_active | active_links);

		ret = drv_change_sta_links(local, sdata, &sta->sta,
					   old_active,
					   old_active | active_links);
		WARN_ON_ONCE(ret);
	}

	ret = ieee80211_key_switch_links(sdata, rem, add);
	WARN_ON_ONCE(ret);

	list_for_each_entry(sta, &local->sta_list, list) {
		if (sdata != sta->sdata)
			continue;

		__ieee80211_sta_recalc_aggregates(sta, active_links);

		ret = drv_change_sta_links(local, sdata, &sta->sta,
					   old_active | active_links,
					   active_links);
		WARN_ON_ONCE(ret);

		/*
		 * Do it again, just in case - the driver might very
		 * well have called ieee80211_sta_recalc_aggregates()
		 * from there when filling in the new links, which
		 * would set it wrong since the vif's active links are
		 * not switched yet...
		 */
		__ieee80211_sta_recalc_aggregates(sta, active_links);
	}

	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
		struct ieee80211_link_data *link;

		link = sdata_dereference(sdata->link[link_id], sdata);

		ret = ieee80211_link_use_channel(link, &link->conf->chandef,
						 IEEE80211_CHANCTX_SHARED);
		WARN_ON_ONCE(ret);

		ieee80211_link_info_change_notify(sdata, link,
						  BSS_CHANGED_ERP_CTS_PROT |
						  BSS_CHANGED_ERP_PREAMBLE |
						  BSS_CHANGED_ERP_SLOT |
						  BSS_CHANGED_HT |
						  BSS_CHANGED_BASIC_RATES |
						  BSS_CHANGED_BSSID |
						  BSS_CHANGED_CQM |
						  BSS_CHANGED_QOS |
						  BSS_CHANGED_TXPOWER |
						  BSS_CHANGED_BANDWIDTH |
						  BSS_CHANGED_TWT |
						  BSS_CHANGED_HE_OBSS_PD |
						  BSS_CHANGED_HE_BSS_COLOR);
		ieee80211_mgd_set_link_qos_params(link);
	}

	old_active = sdata->vif.active_links;
	sdata->vif.active_links = active_links;

	if (rem) {
		ret = drv_change_vif_links(local, sdata, old_active,
					   active_links, link_confs);
		WARN_ON_ONCE(ret);
	}

	return 0;
}

int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	struct ieee80211_local *local = sdata->local;
	u16 old_active;
	int ret;

	sdata_lock(sdata);
	mutex_lock(&local->sta_mtx);
	mutex_lock(&local->mtx);
	mutex_lock(&local->key_mtx);
	old_active = sdata->vif.active_links;
	if (old_active & active_links) {
		/*
		 * if there's at least one link that stays active across
		 * the change then switch to it (to those) first, and
		 * then enable the additional links
		 */
		ret = _ieee80211_set_active_links(sdata,
						  old_active & active_links);
		if (!ret)
			ret = _ieee80211_set_active_links(sdata, active_links);
	} else {
		/* otherwise switch directly */
		ret = _ieee80211_set_active_links(sdata, active_links);
	}
	mutex_unlock(&local->key_mtx);
	mutex_unlock(&local->mtx);
	mutex_unlock(&local->sta_mtx);
	sdata_unlock(sdata);

	return ret;
}
EXPORT_SYMBOL_GPL(ieee80211_set_active_links);

void ieee80211_set_active_links_async(struct ieee80211_vif *vif,
				      u16 active_links)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);

	if (!ieee80211_sdata_running(sdata))
		return;

	if (sdata->vif.type != NL80211_IFTYPE_STATION)
		return;

	/* cannot activate links that don't exist */
	if (active_links & ~sdata->vif.valid_links)
		return;

	/* nothing to do */
	if (sdata->vif.active_links == active_links)
		return;

	sdata->desired_active_links = active_links;
	schedule_work(&sdata->activate_links_work);
}
EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async);