1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2002-2005, Instant802 Networks, Inc.
4 * Copyright 2005-2006, Devicescape Software, Inc.
5 * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
6 * Copyright 2017 Intel Deutschland GmbH
7 * Copyright (C) 2019, 2022-2026 Intel Corporation
8 */
9
10 #include <linux/kernel.h>
11 #include <linux/rtnetlink.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include "rate.h"
15 #include "ieee80211_i.h"
16 #include "debugfs.h"
17
18 struct rate_control_alg {
19 struct list_head list;
20 const struct rate_control_ops *ops;
21 };
22
23 static LIST_HEAD(rate_ctrl_algs);
24 static DEFINE_MUTEX(rate_ctrl_mutex);
25
26 static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
27 module_param(ieee80211_default_rc_algo, charp, 0644);
28 MODULE_PARM_DESC(ieee80211_default_rc_algo,
29 "Default rate control algorithm for mac80211 to use");
30
rate_control_rate_init(struct link_sta_info * link_sta)31 void rate_control_rate_init(struct link_sta_info *link_sta)
32 {
33 struct sta_info *sta = link_sta->sta;
34 struct ieee80211_local *local = sta->sdata->local;
35 struct rate_control_ref *ref = sta->rate_ctrl;
36 struct ieee80211_sta *ista = &sta->sta;
37 void *priv_sta = sta->rate_ctrl_priv;
38 struct ieee80211_supported_band *sband;
39 struct ieee80211_chanctx_conf *chanctx_conf;
40
41 if (!ref)
42 return;
43
44 /* SW rate control isn't supported with MLO right now */
45 if (WARN_ON(ieee80211_vif_is_mld(&sta->sdata->vif)))
46 return;
47
48 rcu_read_lock();
49
50 chanctx_conf = rcu_dereference(sta->sdata->vif.bss_conf.chanctx_conf);
51 if (WARN_ON(!chanctx_conf)) {
52 rcu_read_unlock();
53 return;
54 }
55
56 sband = local->hw.wiphy->bands[chanctx_conf->def.chan->band];
57
58 /* TODO: check for minstrel_s1g ? */
59 if (sband->band == NL80211_BAND_S1GHZ) {
60 ieee80211_s1g_sta_rate_init(sta);
61 rcu_read_unlock();
62 return;
63 }
64
65 spin_lock_bh(&sta->rate_ctrl_lock);
66 ref->ops->rate_init(ref->priv, sband, &chanctx_conf->def, ista,
67 priv_sta);
68 spin_unlock_bh(&sta->rate_ctrl_lock);
69 rcu_read_unlock();
70 set_sta_flag(sta, WLAN_STA_RATE_CONTROL);
71 }
72
rate_control_rate_init_all_links(struct sta_info * sta)73 void rate_control_rate_init_all_links(struct sta_info *sta)
74 {
75 int link_id;
76
77 for (link_id = 0; link_id < ARRAY_SIZE(sta->link); link_id++) {
78 struct link_sta_info *link_sta;
79
80 link_sta = sdata_dereference(sta->link[link_id], sta->sdata);
81 if (!link_sta)
82 continue;
83
84 rate_control_rate_init(link_sta);
85 }
86 }
87
rate_control_tx_status(struct ieee80211_local * local,struct ieee80211_tx_status * st)88 void rate_control_tx_status(struct ieee80211_local *local,
89 struct ieee80211_tx_status *st)
90 {
91 struct rate_control_ref *ref = local->rate_ctrl;
92 struct sta_info *sta = container_of(st->sta, struct sta_info, sta);
93 void *priv_sta = sta->rate_ctrl_priv;
94 struct ieee80211_supported_band *sband;
95
96 if (!ref || !test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
97 return;
98
99 if (st->info->band >= NUM_NL80211_BANDS)
100 return;
101
102 sband = local->hw.wiphy->bands[st->info->band];
103
104 spin_lock_bh(&sta->rate_ctrl_lock);
105 if (ref->ops->tx_status_ext)
106 ref->ops->tx_status_ext(ref->priv, sband, priv_sta, st);
107 else if (st->skb)
108 ref->ops->tx_status(ref->priv, sband, st->sta, priv_sta, st->skb);
109 else
110 WARN_ON_ONCE(1);
111
112 spin_unlock_bh(&sta->rate_ctrl_lock);
113 }
114
rate_control_rate_update(struct ieee80211_local * local,struct ieee80211_supported_band * sband,struct link_sta_info * link_sta,u32 changed)115 void rate_control_rate_update(struct ieee80211_local *local,
116 struct ieee80211_supported_band *sband,
117 struct link_sta_info *link_sta,
118 u32 changed)
119 {
120 struct rate_control_ref *ref = local->rate_ctrl;
121 struct sta_info *sta = link_sta->sta;
122 struct ieee80211_sta *ista = &sta->sta;
123 void *priv_sta = sta->rate_ctrl_priv;
124 struct ieee80211_chanctx_conf *chanctx_conf;
125
126 if (ref && ref->ops->rate_update) {
127 rcu_read_lock();
128
129 chanctx_conf = rcu_dereference(sta->sdata->vif.bss_conf.chanctx_conf);
130 if (WARN_ON(!chanctx_conf)) {
131 rcu_read_unlock();
132 return;
133 }
134
135 spin_lock_bh(&sta->rate_ctrl_lock);
136 ref->ops->rate_update(ref->priv, sband, &chanctx_conf->def,
137 ista, priv_sta, changed);
138 spin_unlock_bh(&sta->rate_ctrl_lock);
139 rcu_read_unlock();
140 }
141
142 if (sta->uploaded)
143 drv_link_sta_rc_update(local, sta->sdata, link_sta->pub,
144 changed);
145 }
146
ieee80211_rate_control_register(const struct rate_control_ops * ops)147 int ieee80211_rate_control_register(const struct rate_control_ops *ops)
148 {
149 struct rate_control_alg *alg;
150
151 if (!ops->name)
152 return -EINVAL;
153
154 mutex_lock(&rate_ctrl_mutex);
155 list_for_each_entry(alg, &rate_ctrl_algs, list) {
156 if (!strcmp(alg->ops->name, ops->name)) {
157 /* don't register an algorithm twice */
158 WARN_ON(1);
159 mutex_unlock(&rate_ctrl_mutex);
160 return -EALREADY;
161 }
162 }
163
164 alg = kzalloc_obj(*alg);
165 if (alg == NULL) {
166 mutex_unlock(&rate_ctrl_mutex);
167 return -ENOMEM;
168 }
169 alg->ops = ops;
170
171 list_add_tail(&alg->list, &rate_ctrl_algs);
172 mutex_unlock(&rate_ctrl_mutex);
173
174 return 0;
175 }
176 EXPORT_SYMBOL(ieee80211_rate_control_register);
177
ieee80211_rate_control_unregister(const struct rate_control_ops * ops)178 void ieee80211_rate_control_unregister(const struct rate_control_ops *ops)
179 {
180 struct rate_control_alg *alg;
181
182 mutex_lock(&rate_ctrl_mutex);
183 list_for_each_entry(alg, &rate_ctrl_algs, list) {
184 if (alg->ops == ops) {
185 list_del(&alg->list);
186 kfree(alg);
187 break;
188 }
189 }
190 mutex_unlock(&rate_ctrl_mutex);
191 }
192 EXPORT_SYMBOL(ieee80211_rate_control_unregister);
193
194 static const struct rate_control_ops *
ieee80211_try_rate_control_ops_get(const char * name)195 ieee80211_try_rate_control_ops_get(const char *name)
196 {
197 struct rate_control_alg *alg;
198 const struct rate_control_ops *ops = NULL;
199
200 if (!name)
201 return NULL;
202
203 mutex_lock(&rate_ctrl_mutex);
204 list_for_each_entry(alg, &rate_ctrl_algs, list) {
205 if (!strcmp(alg->ops->name, name)) {
206 ops = alg->ops;
207 break;
208 }
209 }
210 mutex_unlock(&rate_ctrl_mutex);
211 return ops;
212 }
213
214 /* Get the rate control algorithm. */
215 static const struct rate_control_ops *
ieee80211_rate_control_ops_get(const char * name)216 ieee80211_rate_control_ops_get(const char *name)
217 {
218 const struct rate_control_ops *ops;
219 const char *alg_name;
220
221 kernel_param_lock(THIS_MODULE);
222 if (!name)
223 alg_name = ieee80211_default_rc_algo;
224 else
225 alg_name = name;
226
227 ops = ieee80211_try_rate_control_ops_get(alg_name);
228 if (!ops && name)
229 /* try default if specific alg requested but not found */
230 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);
231
232 /* Note: check for > 0 is intentional to avoid clang warning */
233 if (!ops && (strlen(CONFIG_MAC80211_RC_DEFAULT) > 0))
234 /* try built-in one if specific alg requested but not found */
235 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
236
237 kernel_param_unlock(THIS_MODULE);
238
239 return ops;
240 }
241
242 #ifdef CONFIG_MAC80211_DEBUGFS
rcname_read(struct file * file,char __user * userbuf,size_t count,loff_t * ppos)243 static ssize_t rcname_read(struct file *file, char __user *userbuf,
244 size_t count, loff_t *ppos)
245 {
246 struct rate_control_ref *ref = file->private_data;
247 int len = strlen(ref->ops->name);
248
249 return simple_read_from_buffer(userbuf, count, ppos,
250 ref->ops->name, len);
251 }
252
253 const struct debugfs_short_fops rcname_ops = {
254 .read = rcname_read,
255 .llseek = default_llseek,
256 };
257 #endif
258
259 static struct rate_control_ref *
rate_control_alloc(const char * name,struct ieee80211_local * local)260 rate_control_alloc(const char *name, struct ieee80211_local *local)
261 {
262 struct rate_control_ref *ref;
263
264 ref = kmalloc_obj(struct rate_control_ref);
265 if (!ref)
266 return NULL;
267 ref->ops = ieee80211_rate_control_ops_get(name);
268 if (!ref->ops)
269 goto free;
270
271 ref->priv = ref->ops->alloc(&local->hw);
272 if (!ref->priv)
273 goto free;
274 return ref;
275
276 free:
277 kfree(ref);
278 return NULL;
279 }
280
rate_control_free(struct ieee80211_local * local,struct rate_control_ref * ctrl_ref)281 static void rate_control_free(struct ieee80211_local *local,
282 struct rate_control_ref *ctrl_ref)
283 {
284 ctrl_ref->ops->free(ctrl_ref->priv);
285
286 #ifdef CONFIG_MAC80211_DEBUGFS
287 debugfs_remove_recursive(local->debugfs.rcdir);
288 local->debugfs.rcdir = NULL;
289 #endif
290
291 kfree(ctrl_ref);
292 }
293
ieee80211_check_rate_mask(struct ieee80211_link_data * link)294 void ieee80211_check_rate_mask(struct ieee80211_link_data *link)
295 {
296 struct ieee80211_sub_if_data *sdata = link->sdata;
297 struct ieee80211_local *local = sdata->local;
298 struct ieee80211_supported_band *sband;
299 u32 user_mask, basic_rates = link->conf->basic_rates;
300 enum nl80211_band band;
301
302 if (WARN_ON(!link->conf->chanreq.oper.chan))
303 return;
304
305 band = link->conf->chanreq.oper.chan->band;
306 if (band == NL80211_BAND_S1GHZ) {
307 /* TODO */
308 return;
309 }
310
311 if (WARN_ON_ONCE(!basic_rates))
312 return;
313
314 user_mask = sdata->rc_rateidx_mask[band];
315 sband = local->hw.wiphy->bands[band];
316
317 if (user_mask & basic_rates)
318 return;
319
320 sdata_dbg(sdata,
321 "no overlap between basic rates (0x%x) and user mask (0x%x on band %d) - clearing the latter",
322 basic_rates, user_mask, band);
323 sdata->rc_rateidx_mask[band] = (1 << sband->n_bitrates) - 1;
324 }
325
rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control * txrc)326 static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc)
327 {
328 struct sk_buff *skb = txrc->skb;
329 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
330
331 return (info->flags & (IEEE80211_TX_CTL_NO_ACK |
332 IEEE80211_TX_CTL_USE_MINRATE)) ||
333 !ieee80211_is_tx_data(skb);
334 }
335
rc_send_low_basicrate(struct ieee80211_tx_rate * rate,u32 basic_rates,struct ieee80211_supported_band * sband)336 static void rc_send_low_basicrate(struct ieee80211_tx_rate *rate,
337 u32 basic_rates,
338 struct ieee80211_supported_band *sband)
339 {
340 u8 i;
341
342 if (sband->band == NL80211_BAND_S1GHZ) {
343 /* TODO */
344 rate->flags |= IEEE80211_TX_RC_S1G_MCS;
345 rate->idx = 0;
346 return;
347 }
348
349 if (basic_rates == 0)
350 return; /* assume basic rates unknown and accept rate */
351 if (rate->idx < 0)
352 return;
353 if (basic_rates & (1 << rate->idx))
354 return; /* selected rate is a basic rate */
355
356 for (i = rate->idx + 1; i <= sband->n_bitrates; i++) {
357 if (basic_rates & (1 << i)) {
358 rate->idx = i;
359 return;
360 }
361 }
362
363 /* could not find a basic rate; use original selection */
364 }
365
__rate_control_send_low(struct ieee80211_hw * hw,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,struct ieee80211_tx_info * info,u32 rate_mask)366 static void __rate_control_send_low(struct ieee80211_hw *hw,
367 struct ieee80211_supported_band *sband,
368 struct ieee80211_sta *sta,
369 struct ieee80211_tx_info *info,
370 u32 rate_mask)
371 {
372 u32 rate_flags = 0;
373 int i;
374
375 /*
376 * Frames that shouldn't use the rate mask could be anything,
377 * even on a different band, so don't take the sta into account
378 * to avoid ending up without rates.
379 */
380 if (info->control.flags & IEEE80211_TX_CTRL_DONT_USE_RATE_MASK)
381 sta = NULL;
382
383 if (sband->band == NL80211_BAND_S1GHZ) {
384 info->control.rates[0].flags |= IEEE80211_TX_RC_S1G_MCS;
385 info->control.rates[0].idx = 0;
386 return;
387 }
388
389 if ((sband->band == NL80211_BAND_2GHZ) &&
390 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
391 rate_flags |= IEEE80211_RATE_ERP_G;
392
393 info->control.rates[0].idx = 0;
394 for (i = 0; i < sband->n_bitrates; i++) {
395 if (!(rate_mask & BIT(i)))
396 continue;
397
398 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
399 continue;
400
401 if (!rate_supported(sta, sband->band, i))
402 continue;
403
404 info->control.rates[0].idx = i;
405 break;
406 }
407 WARN_ONCE(i == sband->n_bitrates,
408 "no supported rates for sta %pM (0x%x, band %d) in rate_mask 0x%x with flags 0x%x\n",
409 sta ? sta->addr : NULL,
410 sta ? sta->deflink.supp_rates[sband->band] : -1,
411 sband->band,
412 rate_mask, rate_flags);
413
414 info->control.rates[0].count =
415 (info->flags & IEEE80211_TX_CTL_NO_ACK) ?
416 1 : hw->max_rate_tries;
417
418 info->control.skip_table = 1;
419 }
420
421
rate_control_send_low(struct ieee80211_sta * pubsta,struct ieee80211_tx_rate_control * txrc)422 static bool rate_control_send_low(struct ieee80211_sta *pubsta,
423 struct ieee80211_tx_rate_control *txrc)
424 {
425 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
426 struct ieee80211_supported_band *sband = txrc->sband;
427 struct sta_info *sta;
428 int mcast_rate;
429 bool use_basicrate = false;
430
431 if (!sband)
432 return false;
433
434 if (!pubsta || rc_no_data_or_no_ack_use_min(txrc)) {
435 __rate_control_send_low(txrc->hw, sband, pubsta, info,
436 txrc->rate_idx_mask);
437
438 if (!pubsta && txrc->bss) {
439 mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
440 if (mcast_rate > 0) {
441 info->control.rates[0].idx = mcast_rate - 1;
442 return true;
443 }
444 use_basicrate = true;
445 } else if (pubsta) {
446 sta = container_of(pubsta, struct sta_info, sta);
447 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
448 use_basicrate = true;
449 }
450
451 if (use_basicrate)
452 rc_send_low_basicrate(&info->control.rates[0],
453 txrc->bss_conf->basic_rates,
454 sband);
455
456 return true;
457 }
458 return false;
459 }
460
rate_idx_match_legacy_mask(s8 * rate_idx,int n_bitrates,u32 mask)461 static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask)
462 {
463 int j;
464
465 /* See whether the selected rate or anything below it is allowed. */
466 for (j = *rate_idx; j >= 0; j--) {
467 if (mask & (1 << j)) {
468 /* Okay, found a suitable rate. Use it. */
469 *rate_idx = j;
470 return true;
471 }
472 }
473
474 /* Try to find a higher rate that would be allowed */
475 for (j = *rate_idx + 1; j < n_bitrates; j++) {
476 if (mask & (1 << j)) {
477 /* Okay, found a suitable rate. Use it. */
478 *rate_idx = j;
479 return true;
480 }
481 }
482 return false;
483 }
484
rate_idx_match_mcs_mask(s8 * rate_idx,u8 * mcs_mask)485 static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask)
486 {
487 int i, j;
488 int ridx, rbit;
489
490 ridx = *rate_idx / 8;
491 rbit = *rate_idx % 8;
492
493 /* sanity check */
494 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN)
495 return false;
496
497 /* See whether the selected rate or anything below it is allowed. */
498 for (i = ridx; i >= 0; i--) {
499 for (j = rbit; j >= 0; j--)
500 if (mcs_mask[i] & BIT(j)) {
501 *rate_idx = i * 8 + j;
502 return true;
503 }
504 rbit = 7;
505 }
506
507 /* Try to find a higher rate that would be allowed */
508 ridx = (*rate_idx + 1) / 8;
509 rbit = (*rate_idx + 1) % 8;
510
511 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
512 for (j = rbit; j < 8; j++)
513 if (mcs_mask[i] & BIT(j)) {
514 *rate_idx = i * 8 + j;
515 return true;
516 }
517 rbit = 0;
518 }
519 return false;
520 }
521
rate_idx_match_vht_mcs_mask(s8 * rate_idx,u16 * vht_mask)522 static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask)
523 {
524 int i, j;
525 int ridx, rbit;
526
527 ridx = *rate_idx >> 4;
528 rbit = *rate_idx & 0xf;
529
530 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX)
531 return false;
532
533 /* See whether the selected rate or anything below it is allowed. */
534 for (i = ridx; i >= 0; i--) {
535 for (j = rbit; j >= 0; j--) {
536 if (vht_mask[i] & BIT(j)) {
537 *rate_idx = (i << 4) | j;
538 return true;
539 }
540 }
541 rbit = 15;
542 }
543
544 /* Try to find a higher rate that would be allowed */
545 ridx = (*rate_idx + 1) >> 4;
546 rbit = (*rate_idx + 1) & 0xf;
547
548 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) {
549 for (j = rbit; j < 16; j++) {
550 if (vht_mask[i] & BIT(j)) {
551 *rate_idx = (i << 4) | j;
552 return true;
553 }
554 }
555 rbit = 0;
556 }
557 return false;
558 }
559
rate_idx_match_mask(s8 * rate_idx,u16 * rate_flags,struct ieee80211_supported_band * sband,enum nl80211_chan_width chan_width,u32 mask,u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],u16 vht_mask[NL80211_VHT_NSS_MAX])560 static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags,
561 struct ieee80211_supported_band *sband,
562 enum nl80211_chan_width chan_width,
563 u32 mask,
564 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
565 u16 vht_mask[NL80211_VHT_NSS_MAX])
566 {
567 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) {
568 /* handle VHT rates */
569 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask))
570 return;
571
572 *rate_idx = 0;
573 /* keep protection flags */
574 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
575 IEEE80211_TX_RC_USE_CTS_PROTECT |
576 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
577
578 *rate_flags |= IEEE80211_TX_RC_MCS;
579 if (chan_width == NL80211_CHAN_WIDTH_40)
580 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
581
582 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
583 return;
584
585 /* also try the legacy rates. */
586 *rate_flags &= ~(IEEE80211_TX_RC_MCS |
587 IEEE80211_TX_RC_40_MHZ_WIDTH);
588 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
589 mask))
590 return;
591 } else if (*rate_flags & IEEE80211_TX_RC_MCS) {
592 /* handle HT rates */
593 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
594 return;
595
596 /* also try the legacy rates. */
597 *rate_idx = 0;
598 /* keep protection flags */
599 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
600 IEEE80211_TX_RC_USE_CTS_PROTECT |
601 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
602 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
603 mask))
604 return;
605 } else {
606 /* handle legacy rates */
607 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
608 mask))
609 return;
610
611 /* if HT BSS, and we handle a data frame, also try HT rates */
612 if (chan_width == NL80211_CHAN_WIDTH_20_NOHT)
613 return;
614
615 *rate_idx = 0;
616 /* keep protection flags */
617 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
618 IEEE80211_TX_RC_USE_CTS_PROTECT |
619 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
620
621 *rate_flags |= IEEE80211_TX_RC_MCS;
622
623 if (chan_width == NL80211_CHAN_WIDTH_40)
624 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
625
626 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
627 return;
628 }
629
630 /*
631 * Uh.. No suitable rate exists. This should not really happen with
632 * sane TX rate mask configurations. However, should someone manage to
633 * configure supported rates and TX rate mask in incompatible way,
634 * allow the frame to be transmitted with whatever the rate control
635 * selected.
636 */
637 }
638
rate_fixup_ratelist(struct ieee80211_vif * vif,struct ieee80211_supported_band * sband,struct ieee80211_tx_info * info,struct ieee80211_tx_rate * rates,int max_rates)639 static void rate_fixup_ratelist(struct ieee80211_vif *vif,
640 struct ieee80211_supported_band *sband,
641 struct ieee80211_tx_info *info,
642 struct ieee80211_tx_rate *rates,
643 int max_rates)
644 {
645 struct ieee80211_rate *rate;
646 bool inval = false;
647 int i;
648
649 /*
650 * Set up the RTS/CTS rate as the fastest basic rate
651 * that is not faster than the data rate unless there
652 * is no basic rate slower than the data rate, in which
653 * case we pick the slowest basic rate
654 *
655 * XXX: Should this check all retry rates?
656 */
657 if (!(rates[0].flags &
658 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) {
659 u32 basic_rates = vif->bss_conf.basic_rates;
660 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0;
661
662 rate = &sband->bitrates[rates[0].idx];
663
664 for (i = 0; i < sband->n_bitrates; i++) {
665 /* must be a basic rate */
666 if (!(basic_rates & BIT(i)))
667 continue;
668 /* must not be faster than the data rate */
669 if (sband->bitrates[i].bitrate > rate->bitrate)
670 continue;
671 /* maximum */
672 if (sband->bitrates[baserate].bitrate <
673 sband->bitrates[i].bitrate)
674 baserate = i;
675 }
676
677 info->control.rts_cts_rate_idx = baserate;
678 }
679
680 for (i = 0; i < max_rates; i++) {
681 /*
682 * make sure there's no valid rate following
683 * an invalid one, just in case drivers don't
684 * take the API seriously to stop at -1.
685 */
686 if (inval) {
687 rates[i].idx = -1;
688 continue;
689 }
690 if (rates[i].idx < 0) {
691 inval = true;
692 continue;
693 }
694
695 /*
696 * For now assume MCS is already set up correctly, this
697 * needs to be fixed.
698 */
699 if (rates[i].flags & IEEE80211_TX_RC_MCS) {
700 WARN_ON(rates[i].idx > 76);
701
702 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
703 info->control.use_cts_prot)
704 rates[i].flags |=
705 IEEE80211_TX_RC_USE_CTS_PROTECT;
706 continue;
707 }
708
709 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) {
710 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9);
711 continue;
712 }
713
714 /* set up RTS protection if desired */
715 if (info->control.use_rts) {
716 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS;
717 info->control.use_cts_prot = false;
718 }
719
720 /* RC is busted */
721 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) {
722 rates[i].idx = -1;
723 continue;
724 }
725
726 rate = &sband->bitrates[rates[i].idx];
727
728 /* set up short preamble */
729 if (info->control.short_preamble &&
730 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
731 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
732
733 /* set up G protection */
734 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
735 info->control.use_cts_prot &&
736 rate->flags & IEEE80211_RATE_ERP_G)
737 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
738 }
739 }
740
741
rate_control_fill_sta_table(struct ieee80211_sta * sta,struct ieee80211_tx_info * info,struct ieee80211_tx_rate * rates,int max_rates)742 static void rate_control_fill_sta_table(struct ieee80211_sta *sta,
743 struct ieee80211_tx_info *info,
744 struct ieee80211_tx_rate *rates,
745 int max_rates)
746 {
747 struct ieee80211_sta_rates *ratetbl = NULL;
748 int i;
749
750 if (sta && !info->control.skip_table)
751 ratetbl = rcu_dereference(sta->rates);
752
753 /* Fill remaining rate slots with data from the sta rate table. */
754 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE);
755 for (i = 0; i < max_rates; i++) {
756 if (i < ARRAY_SIZE(info->control.rates) &&
757 info->control.rates[i].idx >= 0 &&
758 info->control.rates[i].count) {
759 if (rates != info->control.rates)
760 rates[i] = info->control.rates[i];
761 } else if (ratetbl) {
762 rates[i].idx = ratetbl->rate[i].idx;
763 rates[i].flags = ratetbl->rate[i].flags;
764 if (info->control.use_rts)
765 rates[i].count = ratetbl->rate[i].count_rts;
766 else if (info->control.use_cts_prot)
767 rates[i].count = ratetbl->rate[i].count_cts;
768 else
769 rates[i].count = ratetbl->rate[i].count;
770 } else {
771 rates[i].idx = -1;
772 rates[i].count = 0;
773 }
774
775 if (rates[i].idx < 0 || !rates[i].count)
776 break;
777 }
778 }
779
rate_control_cap_mask(struct ieee80211_sub_if_data * sdata,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,u32 * mask,u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],u16 vht_mask[NL80211_VHT_NSS_MAX])780 static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata,
781 struct ieee80211_supported_band *sband,
782 struct ieee80211_sta *sta, u32 *mask,
783 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
784 u16 vht_mask[NL80211_VHT_NSS_MAX])
785 {
786 u32 i;
787
788 *mask = sdata->rc_rateidx_mask[sband->band];
789
790 if (*mask == (1 << sband->n_bitrates) - 1 &&
791 !sdata->rc_has_mcs_mask[sband->band] &&
792 !sdata->rc_has_vht_mcs_mask[sband->band])
793 return false;
794
795 if (sdata->rc_has_mcs_mask[sband->band])
796 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band],
797 IEEE80211_HT_MCS_MASK_LEN);
798 else
799 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN);
800
801 if (sdata->rc_has_vht_mcs_mask[sband->band])
802 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band],
803 sizeof(u16) * NL80211_VHT_NSS_MAX);
804 else
805 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX);
806
807 if (sta) {
808 __le16 sta_vht_cap;
809 u16 sta_vht_mask[NL80211_VHT_NSS_MAX];
810
811 /* Filter out rates that the STA does not support */
812 *mask &= sta->deflink.supp_rates[sband->band];
813 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++)
814 mcs_mask[i] &= sta->deflink.ht_cap.mcs.rx_mask[i];
815
816 sta_vht_cap = sta->deflink.vht_cap.vht_mcs.rx_mcs_map;
817 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask);
818 for (i = 0; i < NL80211_VHT_NSS_MAX; i++)
819 vht_mask[i] &= sta_vht_mask[i];
820 }
821
822 return true;
823 }
824
825 static void
rate_control_apply_mask_ratetbl(struct sta_info * sta,struct ieee80211_supported_band * sband,struct ieee80211_sta_rates * rates)826 rate_control_apply_mask_ratetbl(struct sta_info *sta,
827 struct ieee80211_supported_band *sband,
828 struct ieee80211_sta_rates *rates)
829 {
830 int i;
831 u32 mask;
832 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
833 u16 vht_mask[NL80211_VHT_NSS_MAX];
834 enum nl80211_chan_width chan_width;
835
836 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask,
837 mcs_mask, vht_mask))
838 return;
839
840 chan_width = sta->sdata->vif.bss_conf.chanreq.oper.width;
841 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) {
842 if (rates->rate[i].idx < 0)
843 break;
844
845 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags,
846 sband, chan_width, mask, mcs_mask,
847 vht_mask);
848 }
849 }
850
rate_control_apply_mask(struct ieee80211_sub_if_data * sdata,struct ieee80211_sta * sta,struct ieee80211_supported_band * sband,struct ieee80211_tx_rate * rates,int max_rates)851 static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata,
852 struct ieee80211_sta *sta,
853 struct ieee80211_supported_band *sband,
854 struct ieee80211_tx_rate *rates,
855 int max_rates)
856 {
857 enum nl80211_chan_width chan_width;
858 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
859 u32 mask;
860 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX];
861 int i;
862
863 /*
864 * Try to enforce the rateidx mask the user wanted. skip this if the
865 * default mask (allow all rates) is used to save some processing for
866 * the common case.
867 */
868 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask,
869 vht_mask))
870 return;
871
872 /*
873 * Make sure the rate index selected for each TX rate is
874 * included in the configured mask and change the rate indexes
875 * if needed.
876 */
877 chan_width = sdata->vif.bss_conf.chanreq.oper.width;
878 for (i = 0; i < max_rates; i++) {
879 /* Skip invalid rates */
880 if (rates[i].idx < 0)
881 break;
882
883 rate_flags = rates[i].flags;
884 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband,
885 chan_width, mask, mcs_mask, vht_mask);
886 rates[i].flags = rate_flags;
887 }
888 }
889
ieee80211_get_tx_rates(struct ieee80211_vif * vif,struct ieee80211_sta * sta,struct sk_buff * skb,struct ieee80211_tx_rate * dest,int max_rates)890 void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
891 struct ieee80211_sta *sta,
892 struct sk_buff *skb,
893 struct ieee80211_tx_rate *dest,
894 int max_rates)
895 {
896 struct ieee80211_sub_if_data *sdata;
897 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
898 struct ieee80211_supported_band *sband;
899 u32 mask = ~0;
900
901 rate_control_fill_sta_table(sta, info, dest, max_rates);
902
903 if (!vif)
904 return;
905
906 sdata = vif_to_sdata(vif);
907 if (info->band >= NUM_NL80211_BANDS)
908 return;
909
910 sband = sdata->local->hw.wiphy->bands[info->band];
911
912 if (ieee80211_is_tx_data(skb))
913 rate_control_apply_mask(sdata, sta, sband, dest, max_rates);
914
915 if (!(info->control.flags & IEEE80211_TX_CTRL_DONT_USE_RATE_MASK))
916 mask = sdata->rc_rateidx_mask[info->band];
917
918 if (dest[0].idx < 0)
919 __rate_control_send_low(&sdata->local->hw, sband, sta, info,
920 mask);
921
922 if (sta)
923 rate_fixup_ratelist(vif, sband, info, dest, max_rates);
924 }
925 EXPORT_SYMBOL(ieee80211_get_tx_rates);
926
rate_control_get_rate(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,struct ieee80211_tx_rate_control * txrc)927 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
928 struct sta_info *sta,
929 struct ieee80211_tx_rate_control *txrc)
930 {
931 struct rate_control_ref *ref = sdata->local->rate_ctrl;
932 void *priv_sta = NULL;
933 struct ieee80211_sta *ista = NULL;
934 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
935 int i;
936
937 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
938 info->control.rates[i].idx = -1;
939 info->control.rates[i].flags = 0;
940 info->control.rates[i].count = 0;
941 }
942
943 if (rate_control_send_low(sta ? &sta->sta : NULL, txrc))
944 return;
945
946 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL))
947 return;
948
949 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) {
950 ista = &sta->sta;
951 priv_sta = sta->rate_ctrl_priv;
952 }
953
954 if (ista) {
955 spin_lock_bh(&sta->rate_ctrl_lock);
956 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
957 spin_unlock_bh(&sta->rate_ctrl_lock);
958 } else {
959 rate_control_send_low(NULL, txrc);
960 }
961
962 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE))
963 return;
964
965 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb,
966 info->control.rates,
967 ARRAY_SIZE(info->control.rates));
968 }
969
rate_control_set_rates(struct ieee80211_hw * hw,struct ieee80211_sta * pubsta,struct ieee80211_sta_rates * rates)970 int rate_control_set_rates(struct ieee80211_hw *hw,
971 struct ieee80211_sta *pubsta,
972 struct ieee80211_sta_rates *rates)
973 {
974 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
975 struct ieee80211_sta_rates *old;
976 struct ieee80211_supported_band *sband;
977
978 sband = ieee80211_get_sband(sta->sdata);
979 if (!sband)
980 return -EINVAL;
981 rate_control_apply_mask_ratetbl(sta, sband, rates);
982 /*
983 * mac80211 guarantees that this function will not be called
984 * concurrently, so the following RCU access is safe, even without
985 * extra locking. This can not be checked easily, so we just set
986 * the condition to true.
987 */
988 old = rcu_dereference_protected(pubsta->rates, true);
989 rcu_assign_pointer(pubsta->rates, rates);
990 if (old)
991 kfree_rcu(old, rcu_head);
992
993 if (sta->uploaded)
994 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
995
996 return 0;
997 }
998 EXPORT_SYMBOL(rate_control_set_rates);
999
ieee80211_init_rate_ctrl_alg(struct ieee80211_local * local,const char * name)1000 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
1001 const char *name)
1002 {
1003 struct rate_control_ref *ref;
1004
1005 ASSERT_RTNL();
1006
1007 if (local->open_count)
1008 return -EBUSY;
1009
1010 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
1011 if (WARN_ON(!local->ops->set_rts_threshold))
1012 return -EINVAL;
1013 return 0;
1014 }
1015
1016 ref = rate_control_alloc(name, local);
1017 if (!ref) {
1018 wiphy_warn(local->hw.wiphy,
1019 "Failed to select rate control algorithm\n");
1020 return -ENOENT;
1021 }
1022
1023 WARN_ON(local->rate_ctrl);
1024 local->rate_ctrl = ref;
1025
1026 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n",
1027 ref->ops->name);
1028
1029 return 0;
1030 }
1031
rate_control_deinitialize(struct ieee80211_local * local)1032 void rate_control_deinitialize(struct ieee80211_local *local)
1033 {
1034 struct rate_control_ref *ref;
1035
1036 ref = local->rate_ctrl;
1037
1038 if (!ref)
1039 return;
1040
1041 local->rate_ctrl = NULL;
1042 rate_control_free(local, ref);
1043 }
1044