Merge branches 'pm-cpuidle' and 'pm-cpufreq'
[linux-2.6-microblaze.git] / net / mac80211 / rate.c
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
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
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
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
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
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 *
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 *
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
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 *
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 }