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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 */
8
9#include <linux/kernel.h>
10#include <linux/rtnetlink.h>
11#include <linux/module.h>
12#include <linux/slab.h>
13#include "rate.h"
14#include "ieee80211_i.h"
15#include "debugfs.h"
16
17struct rate_control_alg {
18 struct list_head list;
19 const struct rate_control_ops *ops;
20};
21
22static LIST_HEAD(rate_ctrl_algs);
23static DEFINE_MUTEX(rate_ctrl_mutex);
24
25static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
26module_param(ieee80211_default_rc_algo, charp, 0644);
27MODULE_PARM_DESC(ieee80211_default_rc_algo,
28 "Default rate control algorithm for mac80211 to use");
29
30void rate_control_rate_init(struct sta_info *sta)
31{
32 struct ieee80211_local *local = sta->sdata->local;
33 struct rate_control_ref *ref = sta->rate_ctrl;
34 struct ieee80211_sta *ista = &sta->sta;
35 void *priv_sta = sta->rate_ctrl_priv;
36 struct ieee80211_supported_band *sband;
37 struct ieee80211_chanctx_conf *chanctx_conf;
38
39 ieee80211_sta_set_rx_nss(sta);
40
41 if (!ref)
42 return;
43
44 rcu_read_lock();
45
46 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf);
47 if (WARN_ON(!chanctx_conf)) {
48 rcu_read_unlock();
49 return;
50 }
51
52 sband = local->hw.wiphy->bands[chanctx_conf->def.chan->band];
53
54 /* TODO: check for minstrel_s1g ? */
55 if (sband->band == NL80211_BAND_S1GHZ) {
56 ieee80211_s1g_sta_rate_init(sta);
57 rcu_read_unlock();
58 return;
59 }
60
61 spin_lock_bh(&sta->rate_ctrl_lock);
62 ref->ops->rate_init(ref->priv, sband, &chanctx_conf->def, ista,
63 priv_sta);
64 spin_unlock_bh(&sta->rate_ctrl_lock);
65 rcu_read_unlock();
66 set_sta_flag(sta, WLAN_STA_RATE_CONTROL);
67}
68
69void rate_control_tx_status(struct ieee80211_local *local,
70 struct ieee80211_supported_band *sband,
71 struct ieee80211_tx_status *st)
72{
73 struct rate_control_ref *ref = local->rate_ctrl;
74 struct sta_info *sta = container_of(st->sta, struct sta_info, sta);
75 void *priv_sta = sta->rate_ctrl_priv;
76
77 if (!ref || !test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
78 return;
79
80 spin_lock_bh(&sta->rate_ctrl_lock);
81 if (ref->ops->tx_status_ext)
82 ref->ops->tx_status_ext(ref->priv, sband, priv_sta, st);
83 else if (st->skb)
84 ref->ops->tx_status(ref->priv, sband, st->sta, priv_sta, st->skb);
85 else
86 WARN_ON_ONCE(1);
87
88 spin_unlock_bh(&sta->rate_ctrl_lock);
89}
90
91void rate_control_rate_update(struct ieee80211_local *local,
92 struct ieee80211_supported_band *sband,
93 struct sta_info *sta, u32 changed)
94{
95 struct rate_control_ref *ref = local->rate_ctrl;
96 struct ieee80211_sta *ista = &sta->sta;
97 void *priv_sta = sta->rate_ctrl_priv;
98 struct ieee80211_chanctx_conf *chanctx_conf;
99
100 if (ref && ref->ops->rate_update) {
101 rcu_read_lock();
102
103 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf);
104 if (WARN_ON(!chanctx_conf)) {
105 rcu_read_unlock();
106 return;
107 }
108
109 spin_lock_bh(&sta->rate_ctrl_lock);
110 ref->ops->rate_update(ref->priv, sband, &chanctx_conf->def,
111 ista, priv_sta, changed);
112 spin_unlock_bh(&sta->rate_ctrl_lock);
113 rcu_read_unlock();
114 }
115 drv_sta_rc_update(local, sta->sdata, &sta->sta, changed);
116}
117
118int ieee80211_rate_control_register(const struct rate_control_ops *ops)
119{
120 struct rate_control_alg *alg;
121
122 if (!ops->name)
123 return -EINVAL;
124
125 mutex_lock(&rate_ctrl_mutex);
126 list_for_each_entry(alg, &rate_ctrl_algs, list) {
127 if (!strcmp(alg->ops->name, ops->name)) {
128 /* don't register an algorithm twice */
129 WARN_ON(1);
130 mutex_unlock(&rate_ctrl_mutex);
131 return -EALREADY;
132 }
133 }
134
135 alg = kzalloc(sizeof(*alg), GFP_KERNEL);
136 if (alg == NULL) {
137 mutex_unlock(&rate_ctrl_mutex);
138 return -ENOMEM;
139 }
140 alg->ops = ops;
141
142 list_add_tail(&alg->list, &rate_ctrl_algs);
143 mutex_unlock(&rate_ctrl_mutex);
144
145 return 0;
146}
147EXPORT_SYMBOL(ieee80211_rate_control_register);
148
149void ieee80211_rate_control_unregister(const struct rate_control_ops *ops)
150{
151 struct rate_control_alg *alg;
152
153 mutex_lock(&rate_ctrl_mutex);
154 list_for_each_entry(alg, &rate_ctrl_algs, list) {
155 if (alg->ops == ops) {
156 list_del(&alg->list);
157 kfree(alg);
158 break;
159 }
160 }
161 mutex_unlock(&rate_ctrl_mutex);
162}
163EXPORT_SYMBOL(ieee80211_rate_control_unregister);
164
165static const struct rate_control_ops *
166ieee80211_try_rate_control_ops_get(const char *name)
167{
168 struct rate_control_alg *alg;
169 const struct rate_control_ops *ops = NULL;
170
171 if (!name)
172 return NULL;
173
174 mutex_lock(&rate_ctrl_mutex);
175 list_for_each_entry(alg, &rate_ctrl_algs, list) {
176 if (!strcmp(alg->ops->name, name)) {
177 ops = alg->ops;
178 break;
179 }
180 }
181 mutex_unlock(&rate_ctrl_mutex);
182 return ops;
183}
184
185/* Get the rate control algorithm. */
186static const struct rate_control_ops *
187ieee80211_rate_control_ops_get(const char *name)
188{
189 const struct rate_control_ops *ops;
190 const char *alg_name;
191
192 kernel_param_lock(THIS_MODULE);
193 if (!name)
194 alg_name = ieee80211_default_rc_algo;
195 else
196 alg_name = name;
197
198 ops = ieee80211_try_rate_control_ops_get(alg_name);
199 if (!ops && name)
200 /* try default if specific alg requested but not found */
201 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);
202
203 /* Note: check for > 0 is intentional to avoid clang warning */
204 if (!ops && (strlen(CONFIG_MAC80211_RC_DEFAULT) > 0))
205 /* try built-in one if specific alg requested but not found */
206 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
207
208 kernel_param_unlock(THIS_MODULE);
209
210 return ops;
211}
212
213#ifdef CONFIG_MAC80211_DEBUGFS
214static ssize_t rcname_read(struct file *file, char __user *userbuf,
215 size_t count, loff_t *ppos)
216{
217 struct rate_control_ref *ref = file->private_data;
218 int len = strlen(ref->ops->name);
219
220 return simple_read_from_buffer(userbuf, count, ppos,
221 ref->ops->name, len);
222}
223
224const struct file_operations rcname_ops = {
225 .read = rcname_read,
226 .open = simple_open,
227 .llseek = default_llseek,
228};
229#endif
230
231static struct rate_control_ref *
232rate_control_alloc(const char *name, struct ieee80211_local *local)
233{
234 struct rate_control_ref *ref;
235
236 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
237 if (!ref)
238 return NULL;
239 ref->ops = ieee80211_rate_control_ops_get(name);
240 if (!ref->ops)
241 goto free;
242
243 ref->priv = ref->ops->alloc(&local->hw);
244 if (!ref->priv)
245 goto free;
246 return ref;
247
248free:
249 kfree(ref);
250 return NULL;
251}
252
253static void rate_control_free(struct ieee80211_local *local,
254 struct rate_control_ref *ctrl_ref)
255{
256 ctrl_ref->ops->free(ctrl_ref->priv);
257
258#ifdef CONFIG_MAC80211_DEBUGFS
259 debugfs_remove_recursive(local->debugfs.rcdir);
260 local->debugfs.rcdir = NULL;
261#endif
262
263 kfree(ctrl_ref);
264}
265
266void ieee80211_check_rate_mask(struct ieee80211_sub_if_data *sdata)
267{
268 struct ieee80211_local *local = sdata->local;
269 struct ieee80211_supported_band *sband;
270 u32 user_mask, basic_rates = sdata->vif.bss_conf.basic_rates;
271 enum nl80211_band band;
272
273 if (WARN_ON(!sdata->vif.bss_conf.chandef.chan))
274 return;
275
276 band = sdata->vif.bss_conf.chandef.chan->band;
277 if (band == NL80211_BAND_S1GHZ) {
278 /* TODO */
279 return;
280 }
281
282 if (WARN_ON_ONCE(!basic_rates))
283 return;
284
285 user_mask = sdata->rc_rateidx_mask[band];
286 sband = local->hw.wiphy->bands[band];
287
288 if (user_mask & basic_rates)
289 return;
290
291 sdata_dbg(sdata,
292 "no overlap between basic rates (0x%x) and user mask (0x%x on band %d) - clearing the latter",
293 basic_rates, user_mask, band);
294 sdata->rc_rateidx_mask[band] = (1 << sband->n_bitrates) - 1;
295}
296
297static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc)
298{
299 struct sk_buff *skb = txrc->skb;
300 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
301
302 return (info->flags & (IEEE80211_TX_CTL_NO_ACK |
303 IEEE80211_TX_CTL_USE_MINRATE)) ||
304 !ieee80211_is_tx_data(skb);
305}
306
307static void rc_send_low_basicrate(struct ieee80211_tx_rate *rate,
308 u32 basic_rates,
309 struct ieee80211_supported_band *sband)
310{
311 u8 i;
312
313 if (sband->band == NL80211_BAND_S1GHZ) {
314 /* TODO */
315 rate->flags |= IEEE80211_TX_RC_S1G_MCS;
316 rate->idx = 0;
317 return;
318 }
319
320 if (basic_rates == 0)
321 return; /* assume basic rates unknown and accept rate */
322 if (rate->idx < 0)
323 return;
324 if (basic_rates & (1 << rate->idx))
325 return; /* selected rate is a basic rate */
326
327 for (i = rate->idx + 1; i <= sband->n_bitrates; i++) {
328 if (basic_rates & (1 << i)) {
329 rate->idx = i;
330 return;
331 }
332 }
333
334 /* could not find a basic rate; use original selection */
335}
336
337static void __rate_control_send_low(struct ieee80211_hw *hw,
338 struct ieee80211_supported_band *sband,
339 struct ieee80211_sta *sta,
340 struct ieee80211_tx_info *info,
341 u32 rate_mask)
342{
343 int i;
344 u32 rate_flags =
345 ieee80211_chandef_rate_flags(&hw->conf.chandef);
346
347 if (sband->band == NL80211_BAND_S1GHZ) {
348 info->control.rates[0].flags |= IEEE80211_TX_RC_S1G_MCS;
349 info->control.rates[0].idx = 0;
350 return;
351 }
352
353 if ((sband->band == NL80211_BAND_2GHZ) &&
354 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
355 rate_flags |= IEEE80211_RATE_ERP_G;
356
357 info->control.rates[0].idx = 0;
358 for (i = 0; i < sband->n_bitrates; i++) {
359 if (!(rate_mask & BIT(i)))
360 continue;
361
362 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
363 continue;
364
365 if (!rate_supported(sta, sband->band, i))
366 continue;
367
368 info->control.rates[0].idx = i;
369 break;
370 }
371 WARN_ONCE(i == sband->n_bitrates,
372 "no supported rates for sta %pM (0x%x, band %d) in rate_mask 0x%x with flags 0x%x\n",
373 sta ? sta->addr : NULL,
374 sta ? sta->supp_rates[sband->band] : -1,
375 sband->band,
376 rate_mask, rate_flags);
377
378 info->control.rates[0].count =
379 (info->flags & IEEE80211_TX_CTL_NO_ACK) ?
380 1 : hw->max_rate_tries;
381
382 info->control.skip_table = 1;
383}
384
385
386static bool rate_control_send_low(struct ieee80211_sta *pubsta,
387 struct ieee80211_tx_rate_control *txrc)
388{
389 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
390 struct ieee80211_supported_band *sband = txrc->sband;
391 struct sta_info *sta;
392 int mcast_rate;
393 bool use_basicrate = false;
394
395 if (!pubsta || rc_no_data_or_no_ack_use_min(txrc)) {
396 __rate_control_send_low(txrc->hw, sband, pubsta, info,
397 txrc->rate_idx_mask);
398
399 if (!pubsta && txrc->bss) {
400 mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
401 if (mcast_rate > 0) {
402 info->control.rates[0].idx = mcast_rate - 1;
403 return true;
404 }
405 use_basicrate = true;
406 } else if (pubsta) {
407 sta = container_of(pubsta, struct sta_info, sta);
408 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
409 use_basicrate = true;
410 }
411
412 if (use_basicrate)
413 rc_send_low_basicrate(&info->control.rates[0],
414 txrc->bss_conf->basic_rates,
415 sband);
416
417 return true;
418 }
419 return false;
420}
421
422static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask)
423{
424 int j;
425
426 /* See whether the selected rate or anything below it is allowed. */
427 for (j = *rate_idx; j >= 0; j--) {
428 if (mask & (1 << j)) {
429 /* Okay, found a suitable rate. Use it. */
430 *rate_idx = j;
431 return true;
432 }
433 }
434
435 /* Try to find a higher rate that would be allowed */
436 for (j = *rate_idx + 1; j < n_bitrates; j++) {
437 if (mask & (1 << j)) {
438 /* Okay, found a suitable rate. Use it. */
439 *rate_idx = j;
440 return true;
441 }
442 }
443 return false;
444}
445
446static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask)
447{
448 int i, j;
449 int ridx, rbit;
450
451 ridx = *rate_idx / 8;
452 rbit = *rate_idx % 8;
453
454 /* sanity check */
455 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN)
456 return false;
457
458 /* See whether the selected rate or anything below it is allowed. */
459 for (i = ridx; i >= 0; i--) {
460 for (j = rbit; j >= 0; j--)
461 if (mcs_mask[i] & BIT(j)) {
462 *rate_idx = i * 8 + j;
463 return true;
464 }
465 rbit = 7;
466 }
467
468 /* Try to find a higher rate that would be allowed */
469 ridx = (*rate_idx + 1) / 8;
470 rbit = (*rate_idx + 1) % 8;
471
472 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
473 for (j = rbit; j < 8; j++)
474 if (mcs_mask[i] & BIT(j)) {
475 *rate_idx = i * 8 + j;
476 return true;
477 }
478 rbit = 0;
479 }
480 return false;
481}
482
483static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask)
484{
485 int i, j;
486 int ridx, rbit;
487
488 ridx = *rate_idx >> 4;
489 rbit = *rate_idx & 0xf;
490
491 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX)
492 return false;
493
494 /* See whether the selected rate or anything below it is allowed. */
495 for (i = ridx; i >= 0; i--) {
496 for (j = rbit; j >= 0; j--) {
497 if (vht_mask[i] & BIT(j)) {
498 *rate_idx = (i << 4) | j;
499 return true;
500 }
501 }
502 rbit = 15;
503 }
504
505 /* Try to find a higher rate that would be allowed */
506 ridx = (*rate_idx + 1) >> 4;
507 rbit = (*rate_idx + 1) & 0xf;
508
509 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) {
510 for (j = rbit; j < 16; j++) {
511 if (vht_mask[i] & BIT(j)) {
512 *rate_idx = (i << 4) | j;
513 return true;
514 }
515 }
516 rbit = 0;
517 }
518 return false;
519}
520
521static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags,
522 struct ieee80211_supported_band *sband,
523 enum nl80211_chan_width chan_width,
524 u32 mask,
525 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
526 u16 vht_mask[NL80211_VHT_NSS_MAX])
527{
528 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) {
529 /* handle VHT rates */
530 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask))
531 return;
532
533 *rate_idx = 0;
534 /* keep protection flags */
535 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
536 IEEE80211_TX_RC_USE_CTS_PROTECT |
537 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
538
539 *rate_flags |= IEEE80211_TX_RC_MCS;
540 if (chan_width == NL80211_CHAN_WIDTH_40)
541 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
542
543 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
544 return;
545
546 /* also try the legacy rates. */
547 *rate_flags &= ~(IEEE80211_TX_RC_MCS |
548 IEEE80211_TX_RC_40_MHZ_WIDTH);
549 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
550 mask))
551 return;
552 } else if (*rate_flags & IEEE80211_TX_RC_MCS) {
553 /* handle HT rates */
554 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
555 return;
556
557 /* also try the legacy rates. */
558 *rate_idx = 0;
559 /* keep protection flags */
560 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
561 IEEE80211_TX_RC_USE_CTS_PROTECT |
562 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
563 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
564 mask))
565 return;
566 } else {
567 /* handle legacy rates */
568 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
569 mask))
570 return;
571
572 /* if HT BSS, and we handle a data frame, also try HT rates */
573 switch (chan_width) {
574 case NL80211_CHAN_WIDTH_20_NOHT:
575 case NL80211_CHAN_WIDTH_5:
576 case NL80211_CHAN_WIDTH_10:
577 return;
578 default:
579 break;
580 }
581
582 *rate_idx = 0;
583 /* keep protection flags */
584 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
585 IEEE80211_TX_RC_USE_CTS_PROTECT |
586 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
587
588 *rate_flags |= IEEE80211_TX_RC_MCS;
589
590 if (chan_width == NL80211_CHAN_WIDTH_40)
591 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
592
593 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
594 return;
595 }
596
597 /*
598 * Uh.. No suitable rate exists. This should not really happen with
599 * sane TX rate mask configurations. However, should someone manage to
600 * configure supported rates and TX rate mask in incompatible way,
601 * allow the frame to be transmitted with whatever the rate control
602 * selected.
603 */
604}
605
606static void rate_fixup_ratelist(struct ieee80211_vif *vif,
607 struct ieee80211_supported_band *sband,
608 struct ieee80211_tx_info *info,
609 struct ieee80211_tx_rate *rates,
610 int max_rates)
611{
612 struct ieee80211_rate *rate;
613 bool inval = false;
614 int i;
615
616 /*
617 * Set up the RTS/CTS rate as the fastest basic rate
618 * that is not faster than the data rate unless there
619 * is no basic rate slower than the data rate, in which
620 * case we pick the slowest basic rate
621 *
622 * XXX: Should this check all retry rates?
623 */
624 if (!(rates[0].flags &
625 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) {
626 u32 basic_rates = vif->bss_conf.basic_rates;
627 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0;
628
629 rate = &sband->bitrates[rates[0].idx];
630
631 for (i = 0; i < sband->n_bitrates; i++) {
632 /* must be a basic rate */
633 if (!(basic_rates & BIT(i)))
634 continue;
635 /* must not be faster than the data rate */
636 if (sband->bitrates[i].bitrate > rate->bitrate)
637 continue;
638 /* maximum */
639 if (sband->bitrates[baserate].bitrate <
640 sband->bitrates[i].bitrate)
641 baserate = i;
642 }
643
644 info->control.rts_cts_rate_idx = baserate;
645 }
646
647 for (i = 0; i < max_rates; i++) {
648 /*
649 * make sure there's no valid rate following
650 * an invalid one, just in case drivers don't
651 * take the API seriously to stop at -1.
652 */
653 if (inval) {
654 rates[i].idx = -1;
655 continue;
656 }
657 if (rates[i].idx < 0) {
658 inval = true;
659 continue;
660 }
661
662 /*
663 * For now assume MCS is already set up correctly, this
664 * needs to be fixed.
665 */
666 if (rates[i].flags & IEEE80211_TX_RC_MCS) {
667 WARN_ON(rates[i].idx > 76);
668
669 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
670 info->control.use_cts_prot)
671 rates[i].flags |=
672 IEEE80211_TX_RC_USE_CTS_PROTECT;
673 continue;
674 }
675
676 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) {
677 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9);
678 continue;
679 }
680
681 /* set up RTS protection if desired */
682 if (info->control.use_rts) {
683 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS;
684 info->control.use_cts_prot = false;
685 }
686
687 /* RC is busted */
688 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) {
689 rates[i].idx = -1;
690 continue;
691 }
692
693 rate = &sband->bitrates[rates[i].idx];
694
695 /* set up short preamble */
696 if (info->control.short_preamble &&
697 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
698 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
699
700 /* set up G protection */
701 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
702 info->control.use_cts_prot &&
703 rate->flags & IEEE80211_RATE_ERP_G)
704 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
705 }
706}
707
708
709static void rate_control_fill_sta_table(struct ieee80211_sta *sta,
710 struct ieee80211_tx_info *info,
711 struct ieee80211_tx_rate *rates,
712 int max_rates)
713{
714 struct ieee80211_sta_rates *ratetbl = NULL;
715 int i;
716
717 if (sta && !info->control.skip_table)
718 ratetbl = rcu_dereference(sta->rates);
719
720 /* Fill remaining rate slots with data from the sta rate table. */
721 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE);
722 for (i = 0; i < max_rates; i++) {
723 if (i < ARRAY_SIZE(info->control.rates) &&
724 info->control.rates[i].idx >= 0 &&
725 info->control.rates[i].count) {
726 if (rates != info->control.rates)
727 rates[i] = info->control.rates[i];
728 } else if (ratetbl) {
729 rates[i].idx = ratetbl->rate[i].idx;
730 rates[i].flags = ratetbl->rate[i].flags;
731 if (info->control.use_rts)
732 rates[i].count = ratetbl->rate[i].count_rts;
733 else if (info->control.use_cts_prot)
734 rates[i].count = ratetbl->rate[i].count_cts;
735 else
736 rates[i].count = ratetbl->rate[i].count;
737 } else {
738 rates[i].idx = -1;
739 rates[i].count = 0;
740 }
741
742 if (rates[i].idx < 0 || !rates[i].count)
743 break;
744 }
745}
746
747static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata,
748 struct ieee80211_supported_band *sband,
749 struct ieee80211_sta *sta, u32 *mask,
750 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
751 u16 vht_mask[NL80211_VHT_NSS_MAX])
752{
753 u32 i, flags;
754
755 *mask = sdata->rc_rateidx_mask[sband->band];
756 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef);
757 for (i = 0; i < sband->n_bitrates; i++) {
758 if ((flags & sband->bitrates[i].flags) != flags)
759 *mask &= ~BIT(i);
760 }
761
762 if (*mask == (1 << sband->n_bitrates) - 1 &&
763 !sdata->rc_has_mcs_mask[sband->band] &&
764 !sdata->rc_has_vht_mcs_mask[sband->band])
765 return false;
766
767 if (sdata->rc_has_mcs_mask[sband->band])
768 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band],
769 IEEE80211_HT_MCS_MASK_LEN);
770 else
771 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN);
772
773 if (sdata->rc_has_vht_mcs_mask[sband->band])
774 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band],
775 sizeof(u16) * NL80211_VHT_NSS_MAX);
776 else
777 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX);
778
779 if (sta) {
780 __le16 sta_vht_cap;
781 u16 sta_vht_mask[NL80211_VHT_NSS_MAX];
782
783 /* Filter out rates that the STA does not support */
784 *mask &= sta->supp_rates[sband->band];
785 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++)
786 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i];
787
788 sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map;
789 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask);
790 for (i = 0; i < NL80211_VHT_NSS_MAX; i++)
791 vht_mask[i] &= sta_vht_mask[i];
792 }
793
794 return true;
795}
796
797static void
798rate_control_apply_mask_ratetbl(struct sta_info *sta,
799 struct ieee80211_supported_band *sband,
800 struct ieee80211_sta_rates *rates)
801{
802 int i;
803 u32 mask;
804 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
805 u16 vht_mask[NL80211_VHT_NSS_MAX];
806 enum nl80211_chan_width chan_width;
807
808 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask,
809 mcs_mask, vht_mask))
810 return;
811
812 chan_width = sta->sdata->vif.bss_conf.chandef.width;
813 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) {
814 if (rates->rate[i].idx < 0)
815 break;
816
817 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags,
818 sband, chan_width, mask, mcs_mask,
819 vht_mask);
820 }
821}
822
823static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata,
824 struct ieee80211_sta *sta,
825 struct ieee80211_supported_band *sband,
826 struct ieee80211_tx_rate *rates,
827 int max_rates)
828{
829 enum nl80211_chan_width chan_width;
830 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
831 u32 mask;
832 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX];
833 int i;
834
835 /*
836 * Try to enforce the rateidx mask the user wanted. skip this if the
837 * default mask (allow all rates) is used to save some processing for
838 * the common case.
839 */
840 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask,
841 vht_mask))
842 return;
843
844 /*
845 * Make sure the rate index selected for each TX rate is
846 * included in the configured mask and change the rate indexes
847 * if needed.
848 */
849 chan_width = sdata->vif.bss_conf.chandef.width;
850 for (i = 0; i < max_rates; i++) {
851 /* Skip invalid rates */
852 if (rates[i].idx < 0)
853 break;
854
855 rate_flags = rates[i].flags;
856 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband,
857 chan_width, mask, mcs_mask, vht_mask);
858 rates[i].flags = rate_flags;
859 }
860}
861
862void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
863 struct ieee80211_sta *sta,
864 struct sk_buff *skb,
865 struct ieee80211_tx_rate *dest,
866 int max_rates)
867{
868 struct ieee80211_sub_if_data *sdata;
869 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
870 struct ieee80211_supported_band *sband;
871
872 rate_control_fill_sta_table(sta, info, dest, max_rates);
873
874 if (!vif)
875 return;
876
877 sdata = vif_to_sdata(vif);
878 sband = sdata->local->hw.wiphy->bands[info->band];
879
880 if (ieee80211_is_tx_data(skb))
881 rate_control_apply_mask(sdata, sta, sband, dest, max_rates);
882
883 if (dest[0].idx < 0)
884 __rate_control_send_low(&sdata->local->hw, sband, sta, info,
885 sdata->rc_rateidx_mask[info->band]);
886
887 if (sta)
888 rate_fixup_ratelist(vif, sband, info, dest, max_rates);
889}
890EXPORT_SYMBOL(ieee80211_get_tx_rates);
891
892void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
893 struct sta_info *sta,
894 struct ieee80211_tx_rate_control *txrc)
895{
896 struct rate_control_ref *ref = sdata->local->rate_ctrl;
897 void *priv_sta = NULL;
898 struct ieee80211_sta *ista = NULL;
899 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
900 int i;
901
902 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
903 info->control.rates[i].idx = -1;
904 info->control.rates[i].flags = 0;
905 info->control.rates[i].count = 0;
906 }
907
908 if (rate_control_send_low(sta ? &sta->sta : NULL, txrc))
909 return;
910
911 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL))
912 return;
913
914 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) {
915 ista = &sta->sta;
916 priv_sta = sta->rate_ctrl_priv;
917 }
918
919 if (ista) {
920 spin_lock_bh(&sta->rate_ctrl_lock);
921 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
922 spin_unlock_bh(&sta->rate_ctrl_lock);
923 } else {
924 rate_control_send_low(NULL, txrc);
925 }
926
927 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE))
928 return;
929
930 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb,
931 info->control.rates,
932 ARRAY_SIZE(info->control.rates));
933}
934
935int rate_control_set_rates(struct ieee80211_hw *hw,
936 struct ieee80211_sta *pubsta,
937 struct ieee80211_sta_rates *rates)
938{
939 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
940 struct ieee80211_sta_rates *old;
941 struct ieee80211_supported_band *sband;
942
943 sband = ieee80211_get_sband(sta->sdata);
944 if (!sband)
945 return -EINVAL;
946 rate_control_apply_mask_ratetbl(sta, sband, rates);
947 /*
948 * mac80211 guarantees that this function will not be called
949 * concurrently, so the following RCU access is safe, even without
950 * extra locking. This can not be checked easily, so we just set
951 * the condition to true.
952 */
953 old = rcu_dereference_protected(pubsta->rates, true);
954 rcu_assign_pointer(pubsta->rates, rates);
955 if (old)
956 kfree_rcu(old, rcu_head);
957
958 if (sta->uploaded)
959 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
960
961 ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta));
962
963 return 0;
964}
965EXPORT_SYMBOL(rate_control_set_rates);
966
967int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
968 const char *name)
969{
970 struct rate_control_ref *ref;
971
972 ASSERT_RTNL();
973
974 if (local->open_count)
975 return -EBUSY;
976
977 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
978 if (WARN_ON(!local->ops->set_rts_threshold))
979 return -EINVAL;
980 return 0;
981 }
982
983 ref = rate_control_alloc(name, local);
984 if (!ref) {
985 wiphy_warn(local->hw.wiphy,
986 "Failed to select rate control algorithm\n");
987 return -ENOENT;
988 }
989
990 WARN_ON(local->rate_ctrl);
991 local->rate_ctrl = ref;
992
993 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n",
994 ref->ops->name);
995
996 return 0;
997}
998
999void rate_control_deinitialize(struct ieee80211_local *local)
1000{
1001 struct rate_control_ref *ref;
1002
1003 ref = local->rate_ctrl;
1004
1005 if (!ref)
1006 return;
1007
1008 local->rate_ctrl = NULL;
1009 rate_control_free(local, ref);
1010}
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, 2022-2024 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
18struct rate_control_alg {
19 struct list_head list;
20 const struct rate_control_ops *ops;
21};
22
23static LIST_HEAD(rate_ctrl_algs);
24static DEFINE_MUTEX(rate_ctrl_mutex);
25
26static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
27module_param(ieee80211_default_rc_algo, charp, 0644);
28MODULE_PARM_DESC(ieee80211_default_rc_algo,
29 "Default rate control algorithm for mac80211 to use");
30
31void 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 ieee80211_sta_init_nss(link_sta);
42
43 if (!ref)
44 return;
45
46 /* SW rate control isn't supported with MLO right now */
47 if (WARN_ON(ieee80211_vif_is_mld(&sta->sdata->vif)))
48 return;
49
50 rcu_read_lock();
51
52 chanctx_conf = rcu_dereference(sta->sdata->vif.bss_conf.chanctx_conf);
53 if (WARN_ON(!chanctx_conf)) {
54 rcu_read_unlock();
55 return;
56 }
57
58 sband = local->hw.wiphy->bands[chanctx_conf->def.chan->band];
59
60 /* TODO: check for minstrel_s1g ? */
61 if (sband->band == NL80211_BAND_S1GHZ) {
62 ieee80211_s1g_sta_rate_init(sta);
63 rcu_read_unlock();
64 return;
65 }
66
67 spin_lock_bh(&sta->rate_ctrl_lock);
68 ref->ops->rate_init(ref->priv, sband, &chanctx_conf->def, ista,
69 priv_sta);
70 spin_unlock_bh(&sta->rate_ctrl_lock);
71 rcu_read_unlock();
72 set_sta_flag(sta, WLAN_STA_RATE_CONTROL);
73}
74
75void rate_control_rate_init_all_links(struct sta_info *sta)
76{
77 int link_id;
78
79 for (link_id = 0; link_id < ARRAY_SIZE(sta->link); link_id++) {
80 struct link_sta_info *link_sta;
81
82 link_sta = sdata_dereference(sta->link[link_id], sta->sdata);
83 if (!link_sta)
84 continue;
85
86 rate_control_rate_init(link_sta);
87 }
88}
89
90void rate_control_tx_status(struct ieee80211_local *local,
91 struct ieee80211_tx_status *st)
92{
93 struct rate_control_ref *ref = local->rate_ctrl;
94 struct sta_info *sta = container_of(st->sta, struct sta_info, sta);
95 void *priv_sta = sta->rate_ctrl_priv;
96 struct ieee80211_supported_band *sband;
97
98 if (!ref || !test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
99 return;
100
101 sband = local->hw.wiphy->bands[st->info->band];
102
103 spin_lock_bh(&sta->rate_ctrl_lock);
104 if (ref->ops->tx_status_ext)
105 ref->ops->tx_status_ext(ref->priv, sband, priv_sta, st);
106 else if (st->skb)
107 ref->ops->tx_status(ref->priv, sband, st->sta, priv_sta, st->skb);
108 else
109 WARN_ON_ONCE(1);
110
111 spin_unlock_bh(&sta->rate_ctrl_lock);
112}
113
114void rate_control_rate_update(struct ieee80211_local *local,
115 struct ieee80211_supported_band *sband,
116 struct link_sta_info *link_sta,
117 u32 changed)
118{
119 struct rate_control_ref *ref = local->rate_ctrl;
120 struct sta_info *sta = link_sta->sta;
121 struct ieee80211_sta *ista = &sta->sta;
122 void *priv_sta = sta->rate_ctrl_priv;
123 struct ieee80211_chanctx_conf *chanctx_conf;
124
125 if (ref && ref->ops->rate_update) {
126 rcu_read_lock();
127
128 chanctx_conf = rcu_dereference(sta->sdata->vif.bss_conf.chanctx_conf);
129 if (WARN_ON(!chanctx_conf)) {
130 rcu_read_unlock();
131 return;
132 }
133
134 spin_lock_bh(&sta->rate_ctrl_lock);
135 ref->ops->rate_update(ref->priv, sband, &chanctx_conf->def,
136 ista, priv_sta, changed);
137 spin_unlock_bh(&sta->rate_ctrl_lock);
138 rcu_read_unlock();
139 }
140
141 if (sta->uploaded)
142 drv_link_sta_rc_update(local, sta->sdata, link_sta->pub,
143 changed);
144}
145
146int ieee80211_rate_control_register(const struct rate_control_ops *ops)
147{
148 struct rate_control_alg *alg;
149
150 if (!ops->name)
151 return -EINVAL;
152
153 mutex_lock(&rate_ctrl_mutex);
154 list_for_each_entry(alg, &rate_ctrl_algs, list) {
155 if (!strcmp(alg->ops->name, ops->name)) {
156 /* don't register an algorithm twice */
157 WARN_ON(1);
158 mutex_unlock(&rate_ctrl_mutex);
159 return -EALREADY;
160 }
161 }
162
163 alg = kzalloc(sizeof(*alg), GFP_KERNEL);
164 if (alg == NULL) {
165 mutex_unlock(&rate_ctrl_mutex);
166 return -ENOMEM;
167 }
168 alg->ops = ops;
169
170 list_add_tail(&alg->list, &rate_ctrl_algs);
171 mutex_unlock(&rate_ctrl_mutex);
172
173 return 0;
174}
175EXPORT_SYMBOL(ieee80211_rate_control_register);
176
177void ieee80211_rate_control_unregister(const struct rate_control_ops *ops)
178{
179 struct rate_control_alg *alg;
180
181 mutex_lock(&rate_ctrl_mutex);
182 list_for_each_entry(alg, &rate_ctrl_algs, list) {
183 if (alg->ops == ops) {
184 list_del(&alg->list);
185 kfree(alg);
186 break;
187 }
188 }
189 mutex_unlock(&rate_ctrl_mutex);
190}
191EXPORT_SYMBOL(ieee80211_rate_control_unregister);
192
193static const struct rate_control_ops *
194ieee80211_try_rate_control_ops_get(const char *name)
195{
196 struct rate_control_alg *alg;
197 const struct rate_control_ops *ops = NULL;
198
199 if (!name)
200 return NULL;
201
202 mutex_lock(&rate_ctrl_mutex);
203 list_for_each_entry(alg, &rate_ctrl_algs, list) {
204 if (!strcmp(alg->ops->name, name)) {
205 ops = alg->ops;
206 break;
207 }
208 }
209 mutex_unlock(&rate_ctrl_mutex);
210 return ops;
211}
212
213/* Get the rate control algorithm. */
214static const struct rate_control_ops *
215ieee80211_rate_control_ops_get(const char *name)
216{
217 const struct rate_control_ops *ops;
218 const char *alg_name;
219
220 kernel_param_lock(THIS_MODULE);
221 if (!name)
222 alg_name = ieee80211_default_rc_algo;
223 else
224 alg_name = name;
225
226 ops = ieee80211_try_rate_control_ops_get(alg_name);
227 if (!ops && name)
228 /* try default if specific alg requested but not found */
229 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);
230
231 /* Note: check for > 0 is intentional to avoid clang warning */
232 if (!ops && (strlen(CONFIG_MAC80211_RC_DEFAULT) > 0))
233 /* try built-in one if specific alg requested but not found */
234 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
235
236 kernel_param_unlock(THIS_MODULE);
237
238 return ops;
239}
240
241#ifdef CONFIG_MAC80211_DEBUGFS
242static ssize_t rcname_read(struct file *file, char __user *userbuf,
243 size_t count, loff_t *ppos)
244{
245 struct rate_control_ref *ref = file->private_data;
246 int len = strlen(ref->ops->name);
247
248 return simple_read_from_buffer(userbuf, count, ppos,
249 ref->ops->name, len);
250}
251
252const struct debugfs_short_fops rcname_ops = {
253 .read = rcname_read,
254 .llseek = default_llseek,
255};
256#endif
257
258static struct rate_control_ref *
259rate_control_alloc(const char *name, struct ieee80211_local *local)
260{
261 struct rate_control_ref *ref;
262
263 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
264 if (!ref)
265 return NULL;
266 ref->ops = ieee80211_rate_control_ops_get(name);
267 if (!ref->ops)
268 goto free;
269
270 ref->priv = ref->ops->alloc(&local->hw);
271 if (!ref->priv)
272 goto free;
273 return ref;
274
275free:
276 kfree(ref);
277 return NULL;
278}
279
280static void rate_control_free(struct ieee80211_local *local,
281 struct rate_control_ref *ctrl_ref)
282{
283 ctrl_ref->ops->free(ctrl_ref->priv);
284
285#ifdef CONFIG_MAC80211_DEBUGFS
286 debugfs_remove_recursive(local->debugfs.rcdir);
287 local->debugfs.rcdir = NULL;
288#endif
289
290 kfree(ctrl_ref);
291}
292
293void ieee80211_check_rate_mask(struct ieee80211_link_data *link)
294{
295 struct ieee80211_sub_if_data *sdata = link->sdata;
296 struct ieee80211_local *local = sdata->local;
297 struct ieee80211_supported_band *sband;
298 u32 user_mask, basic_rates = link->conf->basic_rates;
299 enum nl80211_band band;
300
301 if (WARN_ON(!link->conf->chanreq.oper.chan))
302 return;
303
304 band = link->conf->chanreq.oper.chan->band;
305 if (band == NL80211_BAND_S1GHZ) {
306 /* TODO */
307 return;
308 }
309
310 if (WARN_ON_ONCE(!basic_rates))
311 return;
312
313 user_mask = sdata->rc_rateidx_mask[band];
314 sband = local->hw.wiphy->bands[band];
315
316 if (user_mask & basic_rates)
317 return;
318
319 sdata_dbg(sdata,
320 "no overlap between basic rates (0x%x) and user mask (0x%x on band %d) - clearing the latter",
321 basic_rates, user_mask, band);
322 sdata->rc_rateidx_mask[band] = (1 << sband->n_bitrates) - 1;
323}
324
325static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc)
326{
327 struct sk_buff *skb = txrc->skb;
328 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
329
330 return (info->flags & (IEEE80211_TX_CTL_NO_ACK |
331 IEEE80211_TX_CTL_USE_MINRATE)) ||
332 !ieee80211_is_tx_data(skb);
333}
334
335static void rc_send_low_basicrate(struct ieee80211_tx_rate *rate,
336 u32 basic_rates,
337 struct ieee80211_supported_band *sband)
338{
339 u8 i;
340
341 if (sband->band == NL80211_BAND_S1GHZ) {
342 /* TODO */
343 rate->flags |= IEEE80211_TX_RC_S1G_MCS;
344 rate->idx = 0;
345 return;
346 }
347
348 if (basic_rates == 0)
349 return; /* assume basic rates unknown and accept rate */
350 if (rate->idx < 0)
351 return;
352 if (basic_rates & (1 << rate->idx))
353 return; /* selected rate is a basic rate */
354
355 for (i = rate->idx + 1; i <= sband->n_bitrates; i++) {
356 if (basic_rates & (1 << i)) {
357 rate->idx = i;
358 return;
359 }
360 }
361
362 /* could not find a basic rate; use original selection */
363}
364
365static void __rate_control_send_low(struct ieee80211_hw *hw,
366 struct ieee80211_supported_band *sband,
367 struct ieee80211_sta *sta,
368 struct ieee80211_tx_info *info,
369 u32 rate_mask)
370{
371 int i;
372 u32 rate_flags =
373 ieee80211_chandef_rate_flags(&hw->conf.chandef);
374
375 if (sband->band == NL80211_BAND_S1GHZ) {
376 info->control.rates[0].flags |= IEEE80211_TX_RC_S1G_MCS;
377 info->control.rates[0].idx = 0;
378 return;
379 }
380
381 if ((sband->band == NL80211_BAND_2GHZ) &&
382 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
383 rate_flags |= IEEE80211_RATE_ERP_G;
384
385 info->control.rates[0].idx = 0;
386 for (i = 0; i < sband->n_bitrates; i++) {
387 if (!(rate_mask & BIT(i)))
388 continue;
389
390 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
391 continue;
392
393 if (!rate_supported(sta, sband->band, i))
394 continue;
395
396 info->control.rates[0].idx = i;
397 break;
398 }
399 WARN_ONCE(i == sband->n_bitrates,
400 "no supported rates for sta %pM (0x%x, band %d) in rate_mask 0x%x with flags 0x%x\n",
401 sta ? sta->addr : NULL,
402 sta ? sta->deflink.supp_rates[sband->band] : -1,
403 sband->band,
404 rate_mask, rate_flags);
405
406 info->control.rates[0].count =
407 (info->flags & IEEE80211_TX_CTL_NO_ACK) ?
408 1 : hw->max_rate_tries;
409
410 info->control.skip_table = 1;
411}
412
413
414static bool rate_control_send_low(struct ieee80211_sta *pubsta,
415 struct ieee80211_tx_rate_control *txrc)
416{
417 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
418 struct ieee80211_supported_band *sband = txrc->sband;
419 struct sta_info *sta;
420 int mcast_rate;
421 bool use_basicrate = false;
422
423 if (!pubsta || rc_no_data_or_no_ack_use_min(txrc)) {
424 __rate_control_send_low(txrc->hw, sband, pubsta, info,
425 txrc->rate_idx_mask);
426
427 if (!pubsta && txrc->bss) {
428 mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
429 if (mcast_rate > 0) {
430 info->control.rates[0].idx = mcast_rate - 1;
431 return true;
432 }
433 use_basicrate = true;
434 } else if (pubsta) {
435 sta = container_of(pubsta, struct sta_info, sta);
436 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
437 use_basicrate = true;
438 }
439
440 if (use_basicrate)
441 rc_send_low_basicrate(&info->control.rates[0],
442 txrc->bss_conf->basic_rates,
443 sband);
444
445 return true;
446 }
447 return false;
448}
449
450static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask)
451{
452 int j;
453
454 /* See whether the selected rate or anything below it is allowed. */
455 for (j = *rate_idx; j >= 0; j--) {
456 if (mask & (1 << j)) {
457 /* Okay, found a suitable rate. Use it. */
458 *rate_idx = j;
459 return true;
460 }
461 }
462
463 /* Try to find a higher rate that would be allowed */
464 for (j = *rate_idx + 1; j < n_bitrates; j++) {
465 if (mask & (1 << j)) {
466 /* Okay, found a suitable rate. Use it. */
467 *rate_idx = j;
468 return true;
469 }
470 }
471 return false;
472}
473
474static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask)
475{
476 int i, j;
477 int ridx, rbit;
478
479 ridx = *rate_idx / 8;
480 rbit = *rate_idx % 8;
481
482 /* sanity check */
483 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN)
484 return false;
485
486 /* See whether the selected rate or anything below it is allowed. */
487 for (i = ridx; i >= 0; i--) {
488 for (j = rbit; j >= 0; j--)
489 if (mcs_mask[i] & BIT(j)) {
490 *rate_idx = i * 8 + j;
491 return true;
492 }
493 rbit = 7;
494 }
495
496 /* Try to find a higher rate that would be allowed */
497 ridx = (*rate_idx + 1) / 8;
498 rbit = (*rate_idx + 1) % 8;
499
500 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
501 for (j = rbit; j < 8; j++)
502 if (mcs_mask[i] & BIT(j)) {
503 *rate_idx = i * 8 + j;
504 return true;
505 }
506 rbit = 0;
507 }
508 return false;
509}
510
511static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask)
512{
513 int i, j;
514 int ridx, rbit;
515
516 ridx = *rate_idx >> 4;
517 rbit = *rate_idx & 0xf;
518
519 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX)
520 return false;
521
522 /* See whether the selected rate or anything below it is allowed. */
523 for (i = ridx; i >= 0; i--) {
524 for (j = rbit; j >= 0; j--) {
525 if (vht_mask[i] & BIT(j)) {
526 *rate_idx = (i << 4) | j;
527 return true;
528 }
529 }
530 rbit = 15;
531 }
532
533 /* Try to find a higher rate that would be allowed */
534 ridx = (*rate_idx + 1) >> 4;
535 rbit = (*rate_idx + 1) & 0xf;
536
537 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) {
538 for (j = rbit; j < 16; j++) {
539 if (vht_mask[i] & BIT(j)) {
540 *rate_idx = (i << 4) | j;
541 return true;
542 }
543 }
544 rbit = 0;
545 }
546 return false;
547}
548
549static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags,
550 struct ieee80211_supported_band *sband,
551 enum nl80211_chan_width chan_width,
552 u32 mask,
553 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
554 u16 vht_mask[NL80211_VHT_NSS_MAX])
555{
556 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) {
557 /* handle VHT rates */
558 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask))
559 return;
560
561 *rate_idx = 0;
562 /* keep protection flags */
563 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
564 IEEE80211_TX_RC_USE_CTS_PROTECT |
565 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
566
567 *rate_flags |= IEEE80211_TX_RC_MCS;
568 if (chan_width == NL80211_CHAN_WIDTH_40)
569 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
570
571 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
572 return;
573
574 /* also try the legacy rates. */
575 *rate_flags &= ~(IEEE80211_TX_RC_MCS |
576 IEEE80211_TX_RC_40_MHZ_WIDTH);
577 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
578 mask))
579 return;
580 } else if (*rate_flags & IEEE80211_TX_RC_MCS) {
581 /* handle HT rates */
582 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
583 return;
584
585 /* also try the legacy rates. */
586 *rate_idx = 0;
587 /* keep protection flags */
588 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
589 IEEE80211_TX_RC_USE_CTS_PROTECT |
590 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
591 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
592 mask))
593 return;
594 } else {
595 /* handle legacy rates */
596 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
597 mask))
598 return;
599
600 /* if HT BSS, and we handle a data frame, also try HT rates */
601 switch (chan_width) {
602 case NL80211_CHAN_WIDTH_20_NOHT:
603 case NL80211_CHAN_WIDTH_5:
604 case NL80211_CHAN_WIDTH_10:
605 return;
606 default:
607 break;
608 }
609
610 *rate_idx = 0;
611 /* keep protection flags */
612 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
613 IEEE80211_TX_RC_USE_CTS_PROTECT |
614 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
615
616 *rate_flags |= IEEE80211_TX_RC_MCS;
617
618 if (chan_width == NL80211_CHAN_WIDTH_40)
619 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
620
621 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
622 return;
623 }
624
625 /*
626 * Uh.. No suitable rate exists. This should not really happen with
627 * sane TX rate mask configurations. However, should someone manage to
628 * configure supported rates and TX rate mask in incompatible way,
629 * allow the frame to be transmitted with whatever the rate control
630 * selected.
631 */
632}
633
634static void rate_fixup_ratelist(struct ieee80211_vif *vif,
635 struct ieee80211_supported_band *sband,
636 struct ieee80211_tx_info *info,
637 struct ieee80211_tx_rate *rates,
638 int max_rates)
639{
640 struct ieee80211_rate *rate;
641 bool inval = false;
642 int i;
643
644 /*
645 * Set up the RTS/CTS rate as the fastest basic rate
646 * that is not faster than the data rate unless there
647 * is no basic rate slower than the data rate, in which
648 * case we pick the slowest basic rate
649 *
650 * XXX: Should this check all retry rates?
651 */
652 if (!(rates[0].flags &
653 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) {
654 u32 basic_rates = vif->bss_conf.basic_rates;
655 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0;
656
657 rate = &sband->bitrates[rates[0].idx];
658
659 for (i = 0; i < sband->n_bitrates; i++) {
660 /* must be a basic rate */
661 if (!(basic_rates & BIT(i)))
662 continue;
663 /* must not be faster than the data rate */
664 if (sband->bitrates[i].bitrate > rate->bitrate)
665 continue;
666 /* maximum */
667 if (sband->bitrates[baserate].bitrate <
668 sband->bitrates[i].bitrate)
669 baserate = i;
670 }
671
672 info->control.rts_cts_rate_idx = baserate;
673 }
674
675 for (i = 0; i < max_rates; i++) {
676 /*
677 * make sure there's no valid rate following
678 * an invalid one, just in case drivers don't
679 * take the API seriously to stop at -1.
680 */
681 if (inval) {
682 rates[i].idx = -1;
683 continue;
684 }
685 if (rates[i].idx < 0) {
686 inval = true;
687 continue;
688 }
689
690 /*
691 * For now assume MCS is already set up correctly, this
692 * needs to be fixed.
693 */
694 if (rates[i].flags & IEEE80211_TX_RC_MCS) {
695 WARN_ON(rates[i].idx > 76);
696
697 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
698 info->control.use_cts_prot)
699 rates[i].flags |=
700 IEEE80211_TX_RC_USE_CTS_PROTECT;
701 continue;
702 }
703
704 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) {
705 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9);
706 continue;
707 }
708
709 /* set up RTS protection if desired */
710 if (info->control.use_rts) {
711 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS;
712 info->control.use_cts_prot = false;
713 }
714
715 /* RC is busted */
716 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) {
717 rates[i].idx = -1;
718 continue;
719 }
720
721 rate = &sband->bitrates[rates[i].idx];
722
723 /* set up short preamble */
724 if (info->control.short_preamble &&
725 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
726 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
727
728 /* set up G protection */
729 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
730 info->control.use_cts_prot &&
731 rate->flags & IEEE80211_RATE_ERP_G)
732 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
733 }
734}
735
736
737static void rate_control_fill_sta_table(struct ieee80211_sta *sta,
738 struct ieee80211_tx_info *info,
739 struct ieee80211_tx_rate *rates,
740 int max_rates)
741{
742 struct ieee80211_sta_rates *ratetbl = NULL;
743 int i;
744
745 if (sta && !info->control.skip_table)
746 ratetbl = rcu_dereference(sta->rates);
747
748 /* Fill remaining rate slots with data from the sta rate table. */
749 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE);
750 for (i = 0; i < max_rates; i++) {
751 if (i < ARRAY_SIZE(info->control.rates) &&
752 info->control.rates[i].idx >= 0 &&
753 info->control.rates[i].count) {
754 if (rates != info->control.rates)
755 rates[i] = info->control.rates[i];
756 } else if (ratetbl) {
757 rates[i].idx = ratetbl->rate[i].idx;
758 rates[i].flags = ratetbl->rate[i].flags;
759 if (info->control.use_rts)
760 rates[i].count = ratetbl->rate[i].count_rts;
761 else if (info->control.use_cts_prot)
762 rates[i].count = ratetbl->rate[i].count_cts;
763 else
764 rates[i].count = ratetbl->rate[i].count;
765 } else {
766 rates[i].idx = -1;
767 rates[i].count = 0;
768 }
769
770 if (rates[i].idx < 0 || !rates[i].count)
771 break;
772 }
773}
774
775static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata,
776 struct ieee80211_supported_band *sband,
777 struct ieee80211_sta *sta, u32 *mask,
778 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
779 u16 vht_mask[NL80211_VHT_NSS_MAX])
780{
781 u32 i, flags;
782
783 *mask = sdata->rc_rateidx_mask[sband->band];
784 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chanreq.oper);
785 for (i = 0; i < sband->n_bitrates; i++) {
786 if ((flags & sband->bitrates[i].flags) != flags)
787 *mask &= ~BIT(i);
788 }
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
825static void
826rate_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
851static 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
890void 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 sband = sdata->local->hw.wiphy->bands[info->band];
908
909 if (ieee80211_is_tx_data(skb))
910 rate_control_apply_mask(sdata, sta, sband, dest, max_rates);
911
912 if (!(info->control.flags & IEEE80211_TX_CTRL_DONT_USE_RATE_MASK))
913 mask = sdata->rc_rateidx_mask[info->band];
914
915 if (dest[0].idx < 0)
916 __rate_control_send_low(&sdata->local->hw, sband, sta, info,
917 mask);
918
919 if (sta)
920 rate_fixup_ratelist(vif, sband, info, dest, max_rates);
921}
922EXPORT_SYMBOL(ieee80211_get_tx_rates);
923
924void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
925 struct sta_info *sta,
926 struct ieee80211_tx_rate_control *txrc)
927{
928 struct rate_control_ref *ref = sdata->local->rate_ctrl;
929 void *priv_sta = NULL;
930 struct ieee80211_sta *ista = NULL;
931 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
932 int i;
933
934 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
935 info->control.rates[i].idx = -1;
936 info->control.rates[i].flags = 0;
937 info->control.rates[i].count = 0;
938 }
939
940 if (rate_control_send_low(sta ? &sta->sta : NULL, txrc))
941 return;
942
943 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL))
944 return;
945
946 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) {
947 ista = &sta->sta;
948 priv_sta = sta->rate_ctrl_priv;
949 }
950
951 if (ista) {
952 spin_lock_bh(&sta->rate_ctrl_lock);
953 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
954 spin_unlock_bh(&sta->rate_ctrl_lock);
955 } else {
956 rate_control_send_low(NULL, txrc);
957 }
958
959 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE))
960 return;
961
962 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb,
963 info->control.rates,
964 ARRAY_SIZE(info->control.rates));
965}
966
967int rate_control_set_rates(struct ieee80211_hw *hw,
968 struct ieee80211_sta *pubsta,
969 struct ieee80211_sta_rates *rates)
970{
971 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
972 struct ieee80211_sta_rates *old;
973 struct ieee80211_supported_band *sband;
974
975 sband = ieee80211_get_sband(sta->sdata);
976 if (!sband)
977 return -EINVAL;
978 rate_control_apply_mask_ratetbl(sta, sband, rates);
979 /*
980 * mac80211 guarantees that this function will not be called
981 * concurrently, so the following RCU access is safe, even without
982 * extra locking. This can not be checked easily, so we just set
983 * the condition to true.
984 */
985 old = rcu_dereference_protected(pubsta->rates, true);
986 rcu_assign_pointer(pubsta->rates, rates);
987 if (old)
988 kfree_rcu(old, rcu_head);
989
990 if (sta->uploaded)
991 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
992
993 ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta));
994
995 return 0;
996}
997EXPORT_SYMBOL(rate_control_set_rates);
998
999int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
1000 const char *name)
1001{
1002 struct rate_control_ref *ref;
1003
1004 ASSERT_RTNL();
1005
1006 if (local->open_count)
1007 return -EBUSY;
1008
1009 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
1010 if (WARN_ON(!local->ops->set_rts_threshold))
1011 return -EINVAL;
1012 return 0;
1013 }
1014
1015 ref = rate_control_alloc(name, local);
1016 if (!ref) {
1017 wiphy_warn(local->hw.wiphy,
1018 "Failed to select rate control algorithm\n");
1019 return -ENOENT;
1020 }
1021
1022 WARN_ON(local->rate_ctrl);
1023 local->rate_ctrl = ref;
1024
1025 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n",
1026 ref->ops->name);
1027
1028 return 0;
1029}
1030
1031void rate_control_deinitialize(struct ieee80211_local *local)
1032{
1033 struct rate_control_ref *ref;
1034
1035 ref = local->rate_ctrl;
1036
1037 if (!ref)
1038 return;
1039
1040 local->rate_ctrl = NULL;
1041 rate_control_free(local, ref);
1042}