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