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
17 struct rate_control_alg {
18 struct list_head list;
19 const struct rate_control_ops *ops;
20 };
21
22 static LIST_HEAD(rate_ctrl_algs);
23 static DEFINE_MUTEX(rate_ctrl_mutex);
24
25 static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
26 module_param(ieee80211_default_rc_algo, charp, 0644);
27 MODULE_PARM_DESC(ieee80211_default_rc_algo,
28 "Default rate control algorithm for mac80211 to use");
29
rate_control_rate_init(struct sta_info * sta)30 void 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
rate_control_tx_status(struct ieee80211_local * local,struct ieee80211_supported_band * sband,struct ieee80211_tx_status * st)69 void 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
rate_control_rate_update(struct ieee80211_local * local,struct ieee80211_supported_band * sband,struct sta_info * sta,u32 changed)91 void 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
ieee80211_rate_control_register(const struct rate_control_ops * ops)118 int 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 }
147 EXPORT_SYMBOL(ieee80211_rate_control_register);
148
ieee80211_rate_control_unregister(const struct rate_control_ops * ops)149 void 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 }
163 EXPORT_SYMBOL(ieee80211_rate_control_unregister);
164
165 static const struct rate_control_ops *
ieee80211_try_rate_control_ops_get(const char * name)166 ieee80211_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. */
186 static const struct rate_control_ops *
ieee80211_rate_control_ops_get(const char * name)187 ieee80211_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
rcname_read(struct file * file,char __user * userbuf,size_t count,loff_t * ppos)214 static 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
224 const struct file_operations rcname_ops = {
225 .read = rcname_read,
226 .open = simple_open,
227 .llseek = default_llseek,
228 };
229 #endif
230
231 static struct rate_control_ref *
rate_control_alloc(const char * name,struct ieee80211_local * local)232 rate_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
248 free:
249 kfree(ref);
250 return NULL;
251 }
252
rate_control_free(struct ieee80211_local * local,struct rate_control_ref * ctrl_ref)253 static 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
ieee80211_check_rate_mask(struct ieee80211_sub_if_data * sdata)266 void 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
rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control * txrc)297 static 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_hdr *hdr = (struct ieee80211_hdr *) skb->data;
301 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
302 __le16 fc;
303
304 fc = hdr->frame_control;
305
306 return (info->flags & (IEEE80211_TX_CTL_NO_ACK |
307 IEEE80211_TX_CTL_USE_MINRATE)) ||
308 !ieee80211_is_data(fc);
309 }
310
rc_send_low_basicrate(struct ieee80211_tx_rate * rate,u32 basic_rates,struct ieee80211_supported_band * sband)311 static void rc_send_low_basicrate(struct ieee80211_tx_rate *rate,
312 u32 basic_rates,
313 struct ieee80211_supported_band *sband)
314 {
315 u8 i;
316
317 if (sband->band == NL80211_BAND_S1GHZ) {
318 /* TODO */
319 rate->flags |= IEEE80211_TX_RC_S1G_MCS;
320 rate->idx = 0;
321 return;
322 }
323
324 if (basic_rates == 0)
325 return; /* assume basic rates unknown and accept rate */
326 if (rate->idx < 0)
327 return;
328 if (basic_rates & (1 << rate->idx))
329 return; /* selected rate is a basic rate */
330
331 for (i = rate->idx + 1; i <= sband->n_bitrates; i++) {
332 if (basic_rates & (1 << i)) {
333 rate->idx = i;
334 return;
335 }
336 }
337
338 /* could not find a basic rate; use original selection */
339 }
340
__rate_control_send_low(struct ieee80211_hw * hw,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,struct ieee80211_tx_info * info,u32 rate_mask)341 static void __rate_control_send_low(struct ieee80211_hw *hw,
342 struct ieee80211_supported_band *sband,
343 struct ieee80211_sta *sta,
344 struct ieee80211_tx_info *info,
345 u32 rate_mask)
346 {
347 int i;
348 u32 rate_flags =
349 ieee80211_chandef_rate_flags(&hw->conf.chandef);
350
351 if (sband->band == NL80211_BAND_S1GHZ) {
352 info->control.rates[0].flags |= IEEE80211_TX_RC_S1G_MCS;
353 info->control.rates[0].idx = 0;
354 return;
355 }
356
357 if ((sband->band == NL80211_BAND_2GHZ) &&
358 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
359 rate_flags |= IEEE80211_RATE_ERP_G;
360
361 info->control.rates[0].idx = 0;
362 for (i = 0; i < sband->n_bitrates; i++) {
363 if (!(rate_mask & BIT(i)))
364 continue;
365
366 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
367 continue;
368
369 if (!rate_supported(sta, sband->band, i))
370 continue;
371
372 info->control.rates[0].idx = i;
373 break;
374 }
375 WARN_ONCE(i == sband->n_bitrates,
376 "no supported rates for sta %pM (0x%x, band %d) in rate_mask 0x%x with flags 0x%x\n",
377 sta ? sta->addr : NULL,
378 sta ? sta->supp_rates[sband->band] : -1,
379 sband->band,
380 rate_mask, rate_flags);
381
382 info->control.rates[0].count =
383 (info->flags & IEEE80211_TX_CTL_NO_ACK) ?
384 1 : hw->max_rate_tries;
385
386 info->control.skip_table = 1;
387 }
388
389
rate_control_send_low(struct ieee80211_sta * pubsta,struct ieee80211_tx_rate_control * txrc)390 static bool rate_control_send_low(struct ieee80211_sta *pubsta,
391 struct ieee80211_tx_rate_control *txrc)
392 {
393 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
394 struct ieee80211_supported_band *sband = txrc->sband;
395 struct sta_info *sta;
396 int mcast_rate;
397 bool use_basicrate = false;
398
399 if (!pubsta || rc_no_data_or_no_ack_use_min(txrc)) {
400 __rate_control_send_low(txrc->hw, sband, pubsta, info,
401 txrc->rate_idx_mask);
402
403 if (!pubsta && txrc->bss) {
404 mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
405 if (mcast_rate > 0) {
406 info->control.rates[0].idx = mcast_rate - 1;
407 return true;
408 }
409 use_basicrate = true;
410 } else if (pubsta) {
411 sta = container_of(pubsta, struct sta_info, sta);
412 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
413 use_basicrate = true;
414 }
415
416 if (use_basicrate)
417 rc_send_low_basicrate(&info->control.rates[0],
418 txrc->bss_conf->basic_rates,
419 sband);
420
421 return true;
422 }
423 return false;
424 }
425
rate_idx_match_legacy_mask(s8 * rate_idx,int n_bitrates,u32 mask)426 static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask)
427 {
428 int j;
429
430 /* See whether the selected rate or anything below it is allowed. */
431 for (j = *rate_idx; j >= 0; j--) {
432 if (mask & (1 << j)) {
433 /* Okay, found a suitable rate. Use it. */
434 *rate_idx = j;
435 return true;
436 }
437 }
438
439 /* Try to find a higher rate that would be allowed */
440 for (j = *rate_idx + 1; j < n_bitrates; j++) {
441 if (mask & (1 << j)) {
442 /* Okay, found a suitable rate. Use it. */
443 *rate_idx = j;
444 return true;
445 }
446 }
447 return false;
448 }
449
rate_idx_match_mcs_mask(s8 * rate_idx,u8 * mcs_mask)450 static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask)
451 {
452 int i, j;
453 int ridx, rbit;
454
455 ridx = *rate_idx / 8;
456 rbit = *rate_idx % 8;
457
458 /* sanity check */
459 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN)
460 return false;
461
462 /* See whether the selected rate or anything below it is allowed. */
463 for (i = ridx; i >= 0; i--) {
464 for (j = rbit; j >= 0; j--)
465 if (mcs_mask[i] & BIT(j)) {
466 *rate_idx = i * 8 + j;
467 return true;
468 }
469 rbit = 7;
470 }
471
472 /* Try to find a higher rate that would be allowed */
473 ridx = (*rate_idx + 1) / 8;
474 rbit = (*rate_idx + 1) % 8;
475
476 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
477 for (j = rbit; j < 8; j++)
478 if (mcs_mask[i] & BIT(j)) {
479 *rate_idx = i * 8 + j;
480 return true;
481 }
482 rbit = 0;
483 }
484 return false;
485 }
486
rate_idx_match_vht_mcs_mask(s8 * rate_idx,u16 * vht_mask)487 static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask)
488 {
489 int i, j;
490 int ridx, rbit;
491
492 ridx = *rate_idx >> 4;
493 rbit = *rate_idx & 0xf;
494
495 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX)
496 return false;
497
498 /* See whether the selected rate or anything below it is allowed. */
499 for (i = ridx; i >= 0; i--) {
500 for (j = rbit; j >= 0; j--) {
501 if (vht_mask[i] & BIT(j)) {
502 *rate_idx = (i << 4) | j;
503 return true;
504 }
505 }
506 rbit = 15;
507 }
508
509 /* Try to find a higher rate that would be allowed */
510 ridx = (*rate_idx + 1) >> 4;
511 rbit = (*rate_idx + 1) & 0xf;
512
513 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) {
514 for (j = rbit; j < 16; j++) {
515 if (vht_mask[i] & BIT(j)) {
516 *rate_idx = (i << 4) | j;
517 return true;
518 }
519 }
520 rbit = 0;
521 }
522 return false;
523 }
524
rate_idx_match_mask(s8 * rate_idx,u16 * rate_flags,struct ieee80211_supported_band * sband,enum nl80211_chan_width chan_width,u32 mask,u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],u16 vht_mask[NL80211_VHT_NSS_MAX])525 static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags,
526 struct ieee80211_supported_band *sband,
527 enum nl80211_chan_width chan_width,
528 u32 mask,
529 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
530 u16 vht_mask[NL80211_VHT_NSS_MAX])
531 {
532 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) {
533 /* handle VHT rates */
534 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask))
535 return;
536
537 *rate_idx = 0;
538 /* keep protection flags */
539 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
540 IEEE80211_TX_RC_USE_CTS_PROTECT |
541 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
542
543 *rate_flags |= IEEE80211_TX_RC_MCS;
544 if (chan_width == NL80211_CHAN_WIDTH_40)
545 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
546
547 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
548 return;
549
550 /* also try the legacy rates. */
551 *rate_flags &= ~(IEEE80211_TX_RC_MCS |
552 IEEE80211_TX_RC_40_MHZ_WIDTH);
553 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
554 mask))
555 return;
556 } else if (*rate_flags & IEEE80211_TX_RC_MCS) {
557 /* handle HT rates */
558 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
559 return;
560
561 /* also try the legacy rates. */
562 *rate_idx = 0;
563 /* keep protection flags */
564 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
565 IEEE80211_TX_RC_USE_CTS_PROTECT |
566 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
567 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
568 mask))
569 return;
570 } else {
571 /* handle legacy rates */
572 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
573 mask))
574 return;
575
576 /* if HT BSS, and we handle a data frame, also try HT rates */
577 switch (chan_width) {
578 case NL80211_CHAN_WIDTH_20_NOHT:
579 case NL80211_CHAN_WIDTH_5:
580 case NL80211_CHAN_WIDTH_10:
581 return;
582 default:
583 break;
584 }
585
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
592 *rate_flags |= IEEE80211_TX_RC_MCS;
593
594 if (chan_width == NL80211_CHAN_WIDTH_40)
595 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
596
597 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
598 return;
599 }
600
601 /*
602 * Uh.. No suitable rate exists. This should not really happen with
603 * sane TX rate mask configurations. However, should someone manage to
604 * configure supported rates and TX rate mask in incompatible way,
605 * allow the frame to be transmitted with whatever the rate control
606 * selected.
607 */
608 }
609
rate_fixup_ratelist(struct ieee80211_vif * vif,struct ieee80211_supported_band * sband,struct ieee80211_tx_info * info,struct ieee80211_tx_rate * rates,int max_rates)610 static void rate_fixup_ratelist(struct ieee80211_vif *vif,
611 struct ieee80211_supported_band *sband,
612 struct ieee80211_tx_info *info,
613 struct ieee80211_tx_rate *rates,
614 int max_rates)
615 {
616 struct ieee80211_rate *rate;
617 bool inval = false;
618 int i;
619
620 /*
621 * Set up the RTS/CTS rate as the fastest basic rate
622 * that is not faster than the data rate unless there
623 * is no basic rate slower than the data rate, in which
624 * case we pick the slowest basic rate
625 *
626 * XXX: Should this check all retry rates?
627 */
628 if (!(rates[0].flags &
629 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) {
630 u32 basic_rates = vif->bss_conf.basic_rates;
631 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0;
632
633 rate = &sband->bitrates[rates[0].idx];
634
635 for (i = 0; i < sband->n_bitrates; i++) {
636 /* must be a basic rate */
637 if (!(basic_rates & BIT(i)))
638 continue;
639 /* must not be faster than the data rate */
640 if (sband->bitrates[i].bitrate > rate->bitrate)
641 continue;
642 /* maximum */
643 if (sband->bitrates[baserate].bitrate <
644 sband->bitrates[i].bitrate)
645 baserate = i;
646 }
647
648 info->control.rts_cts_rate_idx = baserate;
649 }
650
651 for (i = 0; i < max_rates; i++) {
652 /*
653 * make sure there's no valid rate following
654 * an invalid one, just in case drivers don't
655 * take the API seriously to stop at -1.
656 */
657 if (inval) {
658 rates[i].idx = -1;
659 continue;
660 }
661 if (rates[i].idx < 0) {
662 inval = true;
663 continue;
664 }
665
666 /*
667 * For now assume MCS is already set up correctly, this
668 * needs to be fixed.
669 */
670 if (rates[i].flags & IEEE80211_TX_RC_MCS) {
671 WARN_ON(rates[i].idx > 76);
672
673 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
674 info->control.use_cts_prot)
675 rates[i].flags |=
676 IEEE80211_TX_RC_USE_CTS_PROTECT;
677 continue;
678 }
679
680 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) {
681 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9);
682 continue;
683 }
684
685 /* set up RTS protection if desired */
686 if (info->control.use_rts) {
687 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS;
688 info->control.use_cts_prot = false;
689 }
690
691 /* RC is busted */
692 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) {
693 rates[i].idx = -1;
694 continue;
695 }
696
697 rate = &sband->bitrates[rates[i].idx];
698
699 /* set up short preamble */
700 if (info->control.short_preamble &&
701 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
702 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
703
704 /* set up G protection */
705 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
706 info->control.use_cts_prot &&
707 rate->flags & IEEE80211_RATE_ERP_G)
708 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
709 }
710 }
711
712
rate_control_fill_sta_table(struct ieee80211_sta * sta,struct ieee80211_tx_info * info,struct ieee80211_tx_rate * rates,int max_rates)713 static void rate_control_fill_sta_table(struct ieee80211_sta *sta,
714 struct ieee80211_tx_info *info,
715 struct ieee80211_tx_rate *rates,
716 int max_rates)
717 {
718 struct ieee80211_sta_rates *ratetbl = NULL;
719 int i;
720
721 if (sta && !info->control.skip_table)
722 ratetbl = rcu_dereference(sta->rates);
723
724 /* Fill remaining rate slots with data from the sta rate table. */
725 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE);
726 for (i = 0; i < max_rates; i++) {
727 if (i < ARRAY_SIZE(info->control.rates) &&
728 info->control.rates[i].idx >= 0 &&
729 info->control.rates[i].count) {
730 if (rates != info->control.rates)
731 rates[i] = info->control.rates[i];
732 } else if (ratetbl) {
733 rates[i].idx = ratetbl->rate[i].idx;
734 rates[i].flags = ratetbl->rate[i].flags;
735 if (info->control.use_rts)
736 rates[i].count = ratetbl->rate[i].count_rts;
737 else if (info->control.use_cts_prot)
738 rates[i].count = ratetbl->rate[i].count_cts;
739 else
740 rates[i].count = ratetbl->rate[i].count;
741 } else {
742 rates[i].idx = -1;
743 rates[i].count = 0;
744 }
745
746 if (rates[i].idx < 0 || !rates[i].count)
747 break;
748 }
749 }
750
rate_control_cap_mask(struct ieee80211_sub_if_data * sdata,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,u32 * mask,u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],u16 vht_mask[NL80211_VHT_NSS_MAX])751 static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata,
752 struct ieee80211_supported_band *sband,
753 struct ieee80211_sta *sta, u32 *mask,
754 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
755 u16 vht_mask[NL80211_VHT_NSS_MAX])
756 {
757 u32 i, flags;
758
759 *mask = sdata->rc_rateidx_mask[sband->band];
760 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef);
761 for (i = 0; i < sband->n_bitrates; i++) {
762 if ((flags & sband->bitrates[i].flags) != flags)
763 *mask &= ~BIT(i);
764 }
765
766 if (*mask == (1 << sband->n_bitrates) - 1 &&
767 !sdata->rc_has_mcs_mask[sband->band] &&
768 !sdata->rc_has_vht_mcs_mask[sband->band])
769 return false;
770
771 if (sdata->rc_has_mcs_mask[sband->band])
772 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band],
773 IEEE80211_HT_MCS_MASK_LEN);
774 else
775 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN);
776
777 if (sdata->rc_has_vht_mcs_mask[sband->band])
778 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band],
779 sizeof(u16) * NL80211_VHT_NSS_MAX);
780 else
781 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX);
782
783 if (sta) {
784 __le16 sta_vht_cap;
785 u16 sta_vht_mask[NL80211_VHT_NSS_MAX];
786
787 /* Filter out rates that the STA does not support */
788 *mask &= sta->supp_rates[sband->band];
789 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++)
790 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i];
791
792 sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map;
793 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask);
794 for (i = 0; i < NL80211_VHT_NSS_MAX; i++)
795 vht_mask[i] &= sta_vht_mask[i];
796 }
797
798 return true;
799 }
800
801 static void
rate_control_apply_mask_ratetbl(struct sta_info * sta,struct ieee80211_supported_band * sband,struct ieee80211_sta_rates * rates)802 rate_control_apply_mask_ratetbl(struct sta_info *sta,
803 struct ieee80211_supported_band *sband,
804 struct ieee80211_sta_rates *rates)
805 {
806 int i;
807 u32 mask;
808 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
809 u16 vht_mask[NL80211_VHT_NSS_MAX];
810 enum nl80211_chan_width chan_width;
811
812 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask,
813 mcs_mask, vht_mask))
814 return;
815
816 chan_width = sta->sdata->vif.bss_conf.chandef.width;
817 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) {
818 if (rates->rate[i].idx < 0)
819 break;
820
821 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags,
822 sband, chan_width, mask, mcs_mask,
823 vht_mask);
824 }
825 }
826
rate_control_apply_mask(struct ieee80211_sub_if_data * sdata,struct ieee80211_sta * sta,struct ieee80211_supported_band * sband,struct ieee80211_tx_rate * rates,int max_rates)827 static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata,
828 struct ieee80211_sta *sta,
829 struct ieee80211_supported_band *sband,
830 struct ieee80211_tx_rate *rates,
831 int max_rates)
832 {
833 enum nl80211_chan_width chan_width;
834 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
835 u32 mask;
836 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX];
837 int i;
838
839 /*
840 * Try to enforce the rateidx mask the user wanted. skip this if the
841 * default mask (allow all rates) is used to save some processing for
842 * the common case.
843 */
844 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask,
845 vht_mask))
846 return;
847
848 /*
849 * Make sure the rate index selected for each TX rate is
850 * included in the configured mask and change the rate indexes
851 * if needed.
852 */
853 chan_width = sdata->vif.bss_conf.chandef.width;
854 for (i = 0; i < max_rates; i++) {
855 /* Skip invalid rates */
856 if (rates[i].idx < 0)
857 break;
858
859 rate_flags = rates[i].flags;
860 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband,
861 chan_width, mask, mcs_mask, vht_mask);
862 rates[i].flags = rate_flags;
863 }
864 }
865
ieee80211_get_tx_rates(struct ieee80211_vif * vif,struct ieee80211_sta * sta,struct sk_buff * skb,struct ieee80211_tx_rate * dest,int max_rates)866 void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
867 struct ieee80211_sta *sta,
868 struct sk_buff *skb,
869 struct ieee80211_tx_rate *dest,
870 int max_rates)
871 {
872 struct ieee80211_sub_if_data *sdata;
873 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
874 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
875 struct ieee80211_supported_band *sband;
876
877 rate_control_fill_sta_table(sta, info, dest, max_rates);
878
879 if (!vif)
880 return;
881
882 sdata = vif_to_sdata(vif);
883 sband = sdata->local->hw.wiphy->bands[info->band];
884
885 if (ieee80211_is_data(hdr->frame_control))
886 rate_control_apply_mask(sdata, sta, sband, dest, max_rates);
887
888 if (dest[0].idx < 0)
889 __rate_control_send_low(&sdata->local->hw, sband, sta, info,
890 sdata->rc_rateidx_mask[info->band]);
891
892 if (sta)
893 rate_fixup_ratelist(vif, sband, info, dest, max_rates);
894 }
895 EXPORT_SYMBOL(ieee80211_get_tx_rates);
896
rate_control_get_rate(struct ieee80211_sub_if_data * sdata,struct sta_info * sta,struct ieee80211_tx_rate_control * txrc)897 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
898 struct sta_info *sta,
899 struct ieee80211_tx_rate_control *txrc)
900 {
901 struct rate_control_ref *ref = sdata->local->rate_ctrl;
902 void *priv_sta = NULL;
903 struct ieee80211_sta *ista = NULL;
904 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
905 int i;
906
907 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
908 info->control.rates[i].idx = -1;
909 info->control.rates[i].flags = 0;
910 info->control.rates[i].count = 0;
911 }
912
913 if (rate_control_send_low(sta ? &sta->sta : NULL, txrc))
914 return;
915
916 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL))
917 return;
918
919 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) {
920 ista = &sta->sta;
921 priv_sta = sta->rate_ctrl_priv;
922 }
923
924 if (ista) {
925 spin_lock_bh(&sta->rate_ctrl_lock);
926 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
927 spin_unlock_bh(&sta->rate_ctrl_lock);
928 } else {
929 rate_control_send_low(NULL, txrc);
930 }
931
932 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE))
933 return;
934
935 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb,
936 info->control.rates,
937 ARRAY_SIZE(info->control.rates));
938 }
939
rate_control_set_rates(struct ieee80211_hw * hw,struct ieee80211_sta * pubsta,struct ieee80211_sta_rates * rates)940 int rate_control_set_rates(struct ieee80211_hw *hw,
941 struct ieee80211_sta *pubsta,
942 struct ieee80211_sta_rates *rates)
943 {
944 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
945 struct ieee80211_sta_rates *old;
946 struct ieee80211_supported_band *sband;
947
948 sband = ieee80211_get_sband(sta->sdata);
949 if (!sband)
950 return -EINVAL;
951 rate_control_apply_mask_ratetbl(sta, sband, rates);
952 /*
953 * mac80211 guarantees that this function will not be called
954 * concurrently, so the following RCU access is safe, even without
955 * extra locking. This can not be checked easily, so we just set
956 * the condition to true.
957 */
958 old = rcu_dereference_protected(pubsta->rates, true);
959 rcu_assign_pointer(pubsta->rates, rates);
960 if (old)
961 kfree_rcu(old, rcu_head);
962
963 if (sta->uploaded)
964 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
965
966 ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta));
967
968 return 0;
969 }
970 EXPORT_SYMBOL(rate_control_set_rates);
971
ieee80211_init_rate_ctrl_alg(struct ieee80211_local * local,const char * name)972 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
973 const char *name)
974 {
975 struct rate_control_ref *ref;
976
977 ASSERT_RTNL();
978
979 if (local->open_count)
980 return -EBUSY;
981
982 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
983 if (WARN_ON(!local->ops->set_rts_threshold))
984 return -EINVAL;
985 return 0;
986 }
987
988 ref = rate_control_alloc(name, local);
989 if (!ref) {
990 wiphy_warn(local->hw.wiphy,
991 "Failed to select rate control algorithm\n");
992 return -ENOENT;
993 }
994
995 WARN_ON(local->rate_ctrl);
996 local->rate_ctrl = ref;
997
998 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n",
999 ref->ops->name);
1000
1001 return 0;
1002 }
1003
rate_control_deinitialize(struct ieee80211_local * local)1004 void rate_control_deinitialize(struct ieee80211_local *local)
1005 {
1006 struct rate_control_ref *ref;
1007
1008 ref = local->rate_ctrl;
1009
1010 if (!ref)
1011 return;
1012
1013 local->rate_ctrl = NULL;
1014 rate_control_free(local, ref);
1015 }
1016