blob: d53355b011f5cf6407367e3c5f1a3e513d1cc08e [file] [log] [blame]
Jiri Bencf0706e82007-05-05 11:45:53 -07001/*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/kernel.h>
Johannes Bergff688082007-07-27 15:43:23 +020012#include <linux/rtnetlink.h>
Paul Gortmaker3a9a2312011-05-27 09:12:25 -040013#include <linux/module.h>
Johannes Bergcc01f9b2014-01-22 10:36:59 +010014#include <linux/slab.h>
Johannes Berg2c8dccc2008-04-08 15:14:40 -040015#include "rate.h"
Jiri Bencf0706e82007-05-05 11:45:53 -070016#include "ieee80211_i.h"
Johannes Berg4b7679a2008-09-18 18:14:18 +020017#include "debugfs.h"
Jiri Bencf0706e82007-05-05 11:45:53 -070018
19struct rate_control_alg {
20 struct list_head list;
Johannes Berg631ad702014-01-20 23:29:34 +010021 const struct rate_control_ops *ops;
Jiri Bencf0706e82007-05-05 11:45:53 -070022};
23
24static LIST_HEAD(rate_ctrl_algs);
25static DEFINE_MUTEX(rate_ctrl_mutex);
26
Stefano Brivioc21b39a2007-12-19 01:26:16 +010027static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
28module_param(ieee80211_default_rc_algo, charp, 0644);
29MODULE_PARM_DESC(ieee80211_default_rc_algo,
30 "Default rate control algorithm for mac80211 to use");
31
Johannes Berg631ad702014-01-20 23:29:34 +010032int ieee80211_rate_control_register(const struct rate_control_ops *ops)
Jiri Bencf0706e82007-05-05 11:45:53 -070033{
34 struct rate_control_alg *alg;
35
Johannes Bergac71c692007-10-28 14:17:44 +010036 if (!ops->name)
37 return -EINVAL;
38
Johannes Berg999acd92007-10-28 14:49:33 +010039 mutex_lock(&rate_ctrl_mutex);
40 list_for_each_entry(alg, &rate_ctrl_algs, list) {
41 if (!strcmp(alg->ops->name, ops->name)) {
42 /* don't register an algorithm twice */
43 WARN_ON(1);
Cyrill Gorcunovb808ab12007-12-13 15:52:11 -080044 mutex_unlock(&rate_ctrl_mutex);
Johannes Berg999acd92007-10-28 14:49:33 +010045 return -EALREADY;
46 }
47 }
48
Yoann Padioleaudd00cc42007-07-19 01:49:03 -070049 alg = kzalloc(sizeof(*alg), GFP_KERNEL);
Jiri Bencf0706e82007-05-05 11:45:53 -070050 if (alg == NULL) {
Johannes Berg999acd92007-10-28 14:49:33 +010051 mutex_unlock(&rate_ctrl_mutex);
Jiri Bencf0706e82007-05-05 11:45:53 -070052 return -ENOMEM;
53 }
Jiri Bencf0706e82007-05-05 11:45:53 -070054 alg->ops = ops;
55
Jiri Bencf0706e82007-05-05 11:45:53 -070056 list_add_tail(&alg->list, &rate_ctrl_algs);
57 mutex_unlock(&rate_ctrl_mutex);
58
59 return 0;
60}
61EXPORT_SYMBOL(ieee80211_rate_control_register);
62
Johannes Berg631ad702014-01-20 23:29:34 +010063void ieee80211_rate_control_unregister(const struct rate_control_ops *ops)
Jiri Bencf0706e82007-05-05 11:45:53 -070064{
65 struct rate_control_alg *alg;
66
67 mutex_lock(&rate_ctrl_mutex);
68 list_for_each_entry(alg, &rate_ctrl_algs, list) {
69 if (alg->ops == ops) {
70 list_del(&alg->list);
Cyrill Gorcunov20880e82007-12-13 16:17:03 -080071 kfree(alg);
Jiri Bencf0706e82007-05-05 11:45:53 -070072 break;
73 }
74 }
75 mutex_unlock(&rate_ctrl_mutex);
Jiri Bencf0706e82007-05-05 11:45:53 -070076}
77EXPORT_SYMBOL(ieee80211_rate_control_unregister);
78
Johannes Berg631ad702014-01-20 23:29:34 +010079static const struct rate_control_ops *
Jiri Bencf0706e82007-05-05 11:45:53 -070080ieee80211_try_rate_control_ops_get(const char *name)
81{
82 struct rate_control_alg *alg;
Johannes Berg631ad702014-01-20 23:29:34 +010083 const struct rate_control_ops *ops = NULL;
Jiri Bencf0706e82007-05-05 11:45:53 -070084
Johannes Bergac71c692007-10-28 14:17:44 +010085 if (!name)
86 return NULL;
87
Jiri Bencf0706e82007-05-05 11:45:53 -070088 mutex_lock(&rate_ctrl_mutex);
89 list_for_each_entry(alg, &rate_ctrl_algs, list) {
Johannes Bergcc01f9b2014-01-22 10:36:59 +010090 if (!strcmp(alg->ops->name, name)) {
91 ops = alg->ops;
92 break;
93 }
Jiri Bencf0706e82007-05-05 11:45:53 -070094 }
95 mutex_unlock(&rate_ctrl_mutex);
96 return ops;
97}
98
Stefano Brivioc21b39a2007-12-19 01:26:16 +010099/* Get the rate control algorithm. */
Johannes Berg631ad702014-01-20 23:29:34 +0100100static const struct rate_control_ops *
Jiri Bencf0706e82007-05-05 11:45:53 -0700101ieee80211_rate_control_ops_get(const char *name)
102{
Johannes Berg631ad702014-01-20 23:29:34 +0100103 const struct rate_control_ops *ops;
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100104 const char *alg_name;
Jiri Bencf0706e82007-05-05 11:45:53 -0700105
Rusty Russelld6d1b652010-08-11 23:04:27 -0600106 kparam_block_sysfs_write(ieee80211_default_rc_algo);
Johannes Bergac71c692007-10-28 14:17:44 +0100107 if (!name)
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100108 alg_name = ieee80211_default_rc_algo;
109 else
110 alg_name = name;
Johannes Bergac71c692007-10-28 14:17:44 +0100111
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100112 ops = ieee80211_try_rate_control_ops_get(alg_name);
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100113 if (!ops && name)
114 /* try default if specific alg requested but not found */
115 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);
116
Johannes Berg4b475892008-01-02 15:17:03 +0100117 /* try built-in one if specific alg requested but not found */
118 if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT))
119 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
Rusty Russelld6d1b652010-08-11 23:04:27 -0600120 kparam_unblock_sysfs_write(ieee80211_default_rc_algo);
Johannes Berg4b475892008-01-02 15:17:03 +0100121
Jiri Bencf0706e82007-05-05 11:45:53 -0700122 return ops;
123}
124
Johannes Berg4b7679a2008-09-18 18:14:18 +0200125#ifdef CONFIG_MAC80211_DEBUGFS
126static ssize_t rcname_read(struct file *file, char __user *userbuf,
127 size_t count, loff_t *ppos)
128{
129 struct rate_control_ref *ref = file->private_data;
130 int len = strlen(ref->ops->name);
131
132 return simple_read_from_buffer(userbuf, count, ppos,
133 ref->ops->name, len);
134}
135
136static const struct file_operations rcname_ops = {
137 .read = rcname_read,
Stephen Boyd234e3402012-04-05 14:25:11 -0700138 .open = simple_open,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200139 .llseek = default_llseek,
Johannes Berg4b7679a2008-09-18 18:14:18 +0200140};
141#endif
142
Andres Salomon209c6712010-02-07 21:47:50 -0500143static struct rate_control_ref *rate_control_alloc(const char *name,
Jiri Bencf0706e82007-05-05 11:45:53 -0700144 struct ieee80211_local *local)
145{
Johannes Berg4b7679a2008-09-18 18:14:18 +0200146 struct dentry *debugfsdir = NULL;
Jiri Bencf0706e82007-05-05 11:45:53 -0700147 struct rate_control_ref *ref;
148
149 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
150 if (!ref)
Johannes Bergcc01f9b2014-01-22 10:36:59 +0100151 return NULL;
Johannes Berg4b7679a2008-09-18 18:14:18 +0200152 ref->local = local;
Jiri Bencf0706e82007-05-05 11:45:53 -0700153 ref->ops = ieee80211_rate_control_ops_get(name);
154 if (!ref->ops)
Johannes Bergcc01f9b2014-01-22 10:36:59 +0100155 goto free;
Johannes Berg4b7679a2008-09-18 18:14:18 +0200156
157#ifdef CONFIG_MAC80211_DEBUGFS
158 debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir);
159 local->debugfs.rcdir = debugfsdir;
Johannes Berg7bcfaf22009-10-27 12:59:03 +0100160 debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops);
Johannes Berg4b7679a2008-09-18 18:14:18 +0200161#endif
162
163 ref->priv = ref->ops->alloc(&local->hw, debugfsdir);
Jiri Bencf0706e82007-05-05 11:45:53 -0700164 if (!ref->priv)
Johannes Bergcc01f9b2014-01-22 10:36:59 +0100165 goto free;
Jiri Bencf0706e82007-05-05 11:45:53 -0700166 return ref;
167
Johannes Bergcc01f9b2014-01-22 10:36:59 +0100168free:
Jiri Bencf0706e82007-05-05 11:45:53 -0700169 kfree(ref);
Jiri Bencf0706e82007-05-05 11:45:53 -0700170 return NULL;
171}
172
Johannes Berg889cbb92012-01-17 10:33:29 +0100173static void rate_control_free(struct rate_control_ref *ctrl_ref)
Jiri Bencf0706e82007-05-05 11:45:53 -0700174{
Jiri Bencf0706e82007-05-05 11:45:53 -0700175 ctrl_ref->ops->free(ctrl_ref->priv);
Johannes Berg4b7679a2008-09-18 18:14:18 +0200176
177#ifdef CONFIG_MAC80211_DEBUGFS
Johannes Berg7bcfaf22009-10-27 12:59:03 +0100178 debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir);
Johannes Berg4b7679a2008-09-18 18:14:18 +0200179 ctrl_ref->local->debugfs.rcdir = NULL;
180#endif
181
Jiri Bencf0706e82007-05-05 11:45:53 -0700182 kfree(ctrl_ref);
183}
184
Rajkumar Manoharanb6f35302011-09-29 20:34:04 +0530185static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc)
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700186{
187 struct sk_buff *skb = txrc->skb;
188 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
189 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
190 __le16 fc;
191
192 fc = hdr->frame_control;
193
Rajkumar Manoharanb6f35302011-09-29 20:34:04 +0530194 return (info->flags & (IEEE80211_TX_CTL_NO_ACK |
195 IEEE80211_TX_CTL_USE_MINRATE)) ||
196 !ieee80211_is_data(fc);
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700197}
198
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700199static void rc_send_low_basicrate(s8 *idx, u32 basic_rates,
Felix Fietkau8f0729b2010-11-11 15:07:23 +0100200 struct ieee80211_supported_band *sband)
Jouni Malinene00cfce2009-12-29 12:59:19 +0200201{
202 u8 i;
203
204 if (basic_rates == 0)
205 return; /* assume basic rates unknown and accept rate */
206 if (*idx < 0)
207 return;
208 if (basic_rates & (1 << *idx))
209 return; /* selected rate is a basic rate */
210
Felix Fietkau8f0729b2010-11-11 15:07:23 +0100211 for (i = *idx + 1; i <= sband->n_bitrates; i++) {
Jouni Malinene00cfce2009-12-29 12:59:19 +0200212 if (basic_rates & (1 << i)) {
213 *idx = i;
214 return;
215 }
216 }
217
218 /* could not find a basic rate; use original selection */
219}
220
Felix Fietkau0d528d82013-04-22 16:14:41 +0200221static void __rate_control_send_low(struct ieee80211_hw *hw,
222 struct ieee80211_supported_band *sband,
223 struct ieee80211_sta *sta,
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200224 struct ieee80211_tx_info *info,
225 u32 rate_mask)
Felix Fietkau0d528d82013-04-22 16:14:41 +0200226{
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200227 int i;
228 u32 rate_flags =
229 ieee80211_chandef_rate_flags(&hw->conf.chandef);
230
231 if ((sband->band == IEEE80211_BAND_2GHZ) &&
232 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
233 rate_flags |= IEEE80211_RATE_ERP_G;
234
235 info->control.rates[0].idx = 0;
236 for (i = 0; i < sband->n_bitrates; i++) {
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200237 if (!(rate_mask & BIT(i)))
238 continue;
239
Andrei Otcheretianski1431fcb2013-10-14 10:46:55 +0200240 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
241 continue;
242
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200243 if (!rate_supported(sta, sband->band, i))
244 continue;
245
246 info->control.rates[0].idx = i;
247 break;
248 }
249 WARN_ON_ONCE(i == sband->n_bitrates);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200250
251 info->control.rates[0].count =
252 (info->flags & IEEE80211_TX_CTL_NO_ACK) ?
253 1 : hw->max_rate_tries;
254
255 info->control.skip_table = 1;
256}
257
Rajkumar Manoharanaad14ce2011-09-25 14:53:31 +0530258
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700259bool rate_control_send_low(struct ieee80211_sta *pubsta,
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700260 void *priv_sta,
261 struct ieee80211_tx_rate_control *txrc)
262{
263 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100264 struct ieee80211_supported_band *sband = txrc->sband;
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700265 struct sta_info *sta;
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100266 int mcast_rate;
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700267 bool use_basicrate = false;
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700268
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700269 if (!pubsta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) {
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200270 __rate_control_send_low(txrc->hw, sband, pubsta, info,
271 txrc->rate_idx_mask);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200272
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700273 if (!pubsta && txrc->bss) {
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100274 mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
275 if (mcast_rate > 0) {
276 info->control.rates[0].idx = mcast_rate - 1;
277 return true;
278 }
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700279 use_basicrate = true;
280 } else if (pubsta) {
281 sta = container_of(pubsta, struct sta_info, sta);
282 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
283 use_basicrate = true;
284 }
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100285
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700286 if (use_basicrate)
287 rc_send_low_basicrate(&info->control.rates[0].idx,
Jouni Malinene00cfce2009-12-29 12:59:19 +0200288 txrc->bss_conf->basic_rates,
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100289 sband);
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700290
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700291 return true;
292 }
293 return false;
294}
295EXPORT_SYMBOL(rate_control_send_low);
296
Simon Wunderlich19468412012-01-28 17:25:33 +0100297static bool rate_idx_match_legacy_mask(struct ieee80211_tx_rate *rate,
298 int n_bitrates, u32 mask)
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200299{
300 int j;
301
302 /* See whether the selected rate or anything below it is allowed. */
303 for (j = rate->idx; j >= 0; j--) {
304 if (mask & (1 << j)) {
305 /* Okay, found a suitable rate. Use it. */
306 rate->idx = j;
Simon Wunderlich19468412012-01-28 17:25:33 +0100307 return true;
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200308 }
309 }
310
311 /* Try to find a higher rate that would be allowed */
312 for (j = rate->idx + 1; j < n_bitrates; j++) {
313 if (mask & (1 << j)) {
314 /* Okay, found a suitable rate. Use it. */
315 rate->idx = j;
Simon Wunderlich19468412012-01-28 17:25:33 +0100316 return true;
317 }
318 }
319 return false;
320}
321
322static bool rate_idx_match_mcs_mask(struct ieee80211_tx_rate *rate,
323 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
324{
325 int i, j;
326 int ridx, rbit;
327
328 ridx = rate->idx / 8;
329 rbit = rate->idx % 8;
330
331 /* sanity check */
Dan Carpenter910570b52012-02-01 10:42:11 +0300332 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN)
Simon Wunderlich19468412012-01-28 17:25:33 +0100333 return false;
334
335 /* See whether the selected rate or anything below it is allowed. */
336 for (i = ridx; i >= 0; i--) {
337 for (j = rbit; j >= 0; j--)
338 if (mcs_mask[i] & BIT(j)) {
339 rate->idx = i * 8 + j;
340 return true;
341 }
342 rbit = 7;
343 }
344
345 /* Try to find a higher rate that would be allowed */
346 ridx = (rate->idx + 1) / 8;
347 rbit = (rate->idx + 1) % 8;
348
349 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
350 for (j = rbit; j < 8; j++)
351 if (mcs_mask[i] & BIT(j)) {
352 rate->idx = i * 8 + j;
353 return true;
354 }
355 rbit = 0;
356 }
357 return false;
358}
359
360
361
362static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
Felix Fietkau0d528d82013-04-22 16:14:41 +0200363 struct ieee80211_supported_band *sband,
364 enum nl80211_chan_width chan_width,
Simon Wunderlich19468412012-01-28 17:25:33 +0100365 u32 mask,
366 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
367{
368 struct ieee80211_tx_rate alt_rate;
369
370 /* handle HT rates */
371 if (rate->flags & IEEE80211_TX_RC_MCS) {
372 if (rate_idx_match_mcs_mask(rate, mcs_mask))
373 return;
374
375 /* also try the legacy rates. */
376 alt_rate.idx = 0;
377 /* keep protection flags */
378 alt_rate.flags = rate->flags &
379 (IEEE80211_TX_RC_USE_RTS_CTS |
380 IEEE80211_TX_RC_USE_CTS_PROTECT |
381 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
382 alt_rate.count = rate->count;
383 if (rate_idx_match_legacy_mask(&alt_rate,
Felix Fietkau0d528d82013-04-22 16:14:41 +0200384 sband->n_bitrates, mask)) {
Simon Wunderlich19468412012-01-28 17:25:33 +0100385 *rate = alt_rate;
386 return;
387 }
Felix Fietkau628c0102014-11-15 03:48:54 +0100388 } else if (!(rate->flags & IEEE80211_TX_RC_VHT_MCS)) {
Simon Wunderlich19468412012-01-28 17:25:33 +0100389 /* handle legacy rates */
Felix Fietkau0d528d82013-04-22 16:14:41 +0200390 if (rate_idx_match_legacy_mask(rate, sband->n_bitrates, mask))
Simon Wunderlich19468412012-01-28 17:25:33 +0100391 return;
392
393 /* if HT BSS, and we handle a data frame, also try HT rates */
Simon Wunderlich0418a442013-05-16 13:00:31 +0200394 switch (chan_width) {
395 case NL80211_CHAN_WIDTH_20_NOHT:
396 case NL80211_CHAN_WIDTH_5:
397 case NL80211_CHAN_WIDTH_10:
Simon Wunderlich19468412012-01-28 17:25:33 +0100398 return;
Simon Wunderlich0418a442013-05-16 13:00:31 +0200399 default:
400 break;
401 }
Simon Wunderlich19468412012-01-28 17:25:33 +0100402
403 alt_rate.idx = 0;
404 /* keep protection flags */
405 alt_rate.flags = rate->flags &
406 (IEEE80211_TX_RC_USE_RTS_CTS |
407 IEEE80211_TX_RC_USE_CTS_PROTECT |
408 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
409 alt_rate.count = rate->count;
410
411 alt_rate.flags |= IEEE80211_TX_RC_MCS;
412
Felix Fietkau0d528d82013-04-22 16:14:41 +0200413 if (chan_width == NL80211_CHAN_WIDTH_40)
Simon Wunderlich19468412012-01-28 17:25:33 +0100414 alt_rate.flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
415
416 if (rate_idx_match_mcs_mask(&alt_rate, mcs_mask)) {
417 *rate = alt_rate;
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200418 return;
419 }
420 }
421
422 /*
423 * Uh.. No suitable rate exists. This should not really happen with
424 * sane TX rate mask configurations. However, should someone manage to
425 * configure supported rates and TX rate mask in incompatible way,
426 * allow the frame to be transmitted with whatever the rate control
427 * selected.
428 */
429}
430
Felix Fietkau0d528d82013-04-22 16:14:41 +0200431static void rate_fixup_ratelist(struct ieee80211_vif *vif,
432 struct ieee80211_supported_band *sband,
433 struct ieee80211_tx_info *info,
434 struct ieee80211_tx_rate *rates,
435 int max_rates)
436{
437 struct ieee80211_rate *rate;
438 bool inval = false;
439 int i;
440
441 /*
442 * Set up the RTS/CTS rate as the fastest basic rate
443 * that is not faster than the data rate unless there
444 * is no basic rate slower than the data rate, in which
445 * case we pick the slowest basic rate
446 *
447 * XXX: Should this check all retry rates?
448 */
Felix Fietkau336004e2014-11-21 23:29:14 +0100449 if (!(rates[0].flags &
450 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) {
Felix Fietkau0d528d82013-04-22 16:14:41 +0200451 u32 basic_rates = vif->bss_conf.basic_rates;
Karl Beldanc7abf252014-10-13 14:34:41 +0200452 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0;
Felix Fietkau0d528d82013-04-22 16:14:41 +0200453
454 rate = &sband->bitrates[rates[0].idx];
455
456 for (i = 0; i < sband->n_bitrates; i++) {
457 /* must be a basic rate */
458 if (!(basic_rates & BIT(i)))
459 continue;
460 /* must not be faster than the data rate */
461 if (sband->bitrates[i].bitrate > rate->bitrate)
462 continue;
463 /* maximum */
464 if (sband->bitrates[baserate].bitrate <
465 sband->bitrates[i].bitrate)
466 baserate = i;
467 }
468
469 info->control.rts_cts_rate_idx = baserate;
470 }
471
472 for (i = 0; i < max_rates; i++) {
473 /*
474 * make sure there's no valid rate following
475 * an invalid one, just in case drivers don't
476 * take the API seriously to stop at -1.
477 */
478 if (inval) {
479 rates[i].idx = -1;
480 continue;
481 }
482 if (rates[i].idx < 0) {
483 inval = true;
484 continue;
485 }
486
487 /*
488 * For now assume MCS is already set up correctly, this
489 * needs to be fixed.
490 */
491 if (rates[i].flags & IEEE80211_TX_RC_MCS) {
492 WARN_ON(rates[i].idx > 76);
493
494 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
495 info->control.use_cts_prot)
496 rates[i].flags |=
497 IEEE80211_TX_RC_USE_CTS_PROTECT;
498 continue;
499 }
500
501 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) {
502 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9);
503 continue;
504 }
505
506 /* set up RTS protection if desired */
507 if (info->control.use_rts) {
508 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS;
509 info->control.use_cts_prot = false;
510 }
511
512 /* RC is busted */
513 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) {
514 rates[i].idx = -1;
515 continue;
516 }
517
518 rate = &sband->bitrates[rates[i].idx];
519
520 /* set up short preamble */
521 if (info->control.short_preamble &&
522 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
523 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
524
525 /* set up G protection */
526 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
527 info->control.use_cts_prot &&
528 rate->flags & IEEE80211_RATE_ERP_G)
529 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
530 }
531}
532
533
534static void rate_control_fill_sta_table(struct ieee80211_sta *sta,
535 struct ieee80211_tx_info *info,
536 struct ieee80211_tx_rate *rates,
537 int max_rates)
538{
539 struct ieee80211_sta_rates *ratetbl = NULL;
540 int i;
541
542 if (sta && !info->control.skip_table)
543 ratetbl = rcu_dereference(sta->rates);
544
545 /* Fill remaining rate slots with data from the sta rate table. */
546 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE);
547 for (i = 0; i < max_rates; i++) {
548 if (i < ARRAY_SIZE(info->control.rates) &&
549 info->control.rates[i].idx >= 0 &&
550 info->control.rates[i].count) {
551 if (rates != info->control.rates)
552 rates[i] = info->control.rates[i];
553 } else if (ratetbl) {
554 rates[i].idx = ratetbl->rate[i].idx;
555 rates[i].flags = ratetbl->rate[i].flags;
556 if (info->control.use_rts)
557 rates[i].count = ratetbl->rate[i].count_rts;
558 else if (info->control.use_cts_prot)
559 rates[i].count = ratetbl->rate[i].count_cts;
560 else
561 rates[i].count = ratetbl->rate[i].count;
562 } else {
563 rates[i].idx = -1;
564 rates[i].count = 0;
565 }
566
567 if (rates[i].idx < 0 || !rates[i].count)
568 break;
569 }
570}
571
572static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata,
573 struct ieee80211_sta *sta,
574 struct ieee80211_supported_band *sband,
575 struct ieee80211_tx_info *info,
576 struct ieee80211_tx_rate *rates,
577 int max_rates)
578{
579 enum nl80211_chan_width chan_width;
580 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
581 bool has_mcs_mask;
582 u32 mask;
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200583 u32 rate_flags;
Felix Fietkau0d528d82013-04-22 16:14:41 +0200584 int i;
585
586 /*
587 * Try to enforce the rateidx mask the user wanted. skip this if the
588 * default mask (allow all rates) is used to save some processing for
589 * the common case.
590 */
591 mask = sdata->rc_rateidx_mask[info->band];
592 has_mcs_mask = sdata->rc_has_mcs_mask[info->band];
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200593 rate_flags =
594 ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef);
595 for (i = 0; i < sband->n_bitrates; i++)
596 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
597 mask &= ~BIT(i);
598
Felix Fietkau0d528d82013-04-22 16:14:41 +0200599 if (mask == (1 << sband->n_bitrates) - 1 && !has_mcs_mask)
600 return;
601
602 if (has_mcs_mask)
603 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[info->band],
604 sizeof(mcs_mask));
605 else
606 memset(mcs_mask, 0xff, sizeof(mcs_mask));
607
608 if (sta) {
609 /* Filter out rates that the STA does not support */
610 mask &= sta->supp_rates[info->band];
611 for (i = 0; i < sizeof(mcs_mask); i++)
612 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i];
613 }
614
615 /*
616 * Make sure the rate index selected for each TX rate is
617 * included in the configured mask and change the rate indexes
618 * if needed.
619 */
620 chan_width = sdata->vif.bss_conf.chandef.width;
621 for (i = 0; i < max_rates; i++) {
622 /* Skip invalid rates */
623 if (rates[i].idx < 0)
624 break;
625
Simon Wunderlich795d8552013-06-11 10:44:40 +0200626 rate_idx_match_mask(&rates[i], sband, chan_width, mask,
Felix Fietkau0d528d82013-04-22 16:14:41 +0200627 mcs_mask);
628 }
629}
630
631void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
632 struct ieee80211_sta *sta,
633 struct sk_buff *skb,
634 struct ieee80211_tx_rate *dest,
635 int max_rates)
636{
637 struct ieee80211_sub_if_data *sdata;
638 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
639 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
640 struct ieee80211_supported_band *sband;
641
642 rate_control_fill_sta_table(sta, info, dest, max_rates);
643
644 if (!vif)
645 return;
646
647 sdata = vif_to_sdata(vif);
648 sband = sdata->local->hw.wiphy->bands[info->band];
649
650 if (ieee80211_is_data(hdr->frame_control))
651 rate_control_apply_mask(sdata, sta, sband, info, dest, max_rates);
652
653 if (dest[0].idx < 0)
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200654 __rate_control_send_low(&sdata->local->hw, sband, sta, info,
655 sdata->rc_rateidx_mask[info->band]);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200656
657 if (sta)
658 rate_fixup_ratelist(vif, sband, info, dest, max_rates);
659}
660EXPORT_SYMBOL(ieee80211_get_tx_rates);
661
Johannes Berg4b7679a2008-09-18 18:14:18 +0200662void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
Johannes Berge6a98542008-10-21 12:40:02 +0200663 struct sta_info *sta,
664 struct ieee80211_tx_rate_control *txrc)
Mattias Nissler1abbe492007-12-20 13:50:07 +0100665{
Johannes Berg4b7679a2008-09-18 18:14:18 +0200666 struct rate_control_ref *ref = sdata->local->rate_ctrl;
667 void *priv_sta = NULL;
668 struct ieee80211_sta *ista = NULL;
Johannes Berge6a98542008-10-21 12:40:02 +0200669 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
Mattias Nissler1abbe492007-12-20 13:50:07 +0100670 int i;
Mattias Nissler1abbe492007-12-20 13:50:07 +0100671
Johannes Berge1936e92012-01-20 13:55:23 +0100672 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) {
Johannes Berg4b7679a2008-09-18 18:14:18 +0200673 ista = &sta->sta;
674 priv_sta = sta->rate_ctrl_priv;
675 }
676
Johannes Berge6a98542008-10-21 12:40:02 +0200677 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
678 info->control.rates[i].idx = -1;
679 info->control.rates[i].flags = 0;
Mohammed Shafi Shajakhan8617b092012-02-20 10:05:31 +0530680 info->control.rates[i].count = 0;
Mattias Nissler1abbe492007-12-20 13:50:07 +0100681 }
Johannes Berge6a98542008-10-21 12:40:02 +0200682
Juuso Oikarinen5affcd62010-02-12 10:05:45 +0200683 if (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
684 return;
685
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200686 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
Johannes Berge6a98542008-10-21 12:40:02 +0200687
Felix Fietkau0d528d82013-04-22 16:14:41 +0200688 if (sdata->local->hw.flags & IEEE80211_HW_SUPPORTS_RC_TABLE)
689 return;
Felix Fietkau2ffbe6d2013-04-16 13:38:42 +0200690
Felix Fietkau0d528d82013-04-22 16:14:41 +0200691 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb,
692 info->control.rates,
693 ARRAY_SIZE(info->control.rates));
Mattias Nissler1abbe492007-12-20 13:50:07 +0100694}
695
Felix Fietkau0d528d82013-04-22 16:14:41 +0200696int rate_control_set_rates(struct ieee80211_hw *hw,
697 struct ieee80211_sta *pubsta,
698 struct ieee80211_sta_rates *rates)
699{
Johannes Bergf815e2b2014-11-19 00:10:42 +0100700 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
Felix Fietkauf6b3d852013-05-03 10:01:03 +0200701 struct ieee80211_sta_rates *old;
Felix Fietkau0d528d82013-04-22 16:14:41 +0200702
Felix Fietkauf6b3d852013-05-03 10:01:03 +0200703 /*
704 * mac80211 guarantees that this function will not be called
705 * concurrently, so the following RCU access is safe, even without
706 * extra locking. This can not be checked easily, so we just set
707 * the condition to true.
708 */
709 old = rcu_dereference_protected(pubsta->rates, true);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200710 rcu_assign_pointer(pubsta->rates, rates);
711 if (old)
712 kfree_rcu(old, rcu_head);
713
Johannes Bergf815e2b2014-11-19 00:10:42 +0100714 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
715
Felix Fietkau0d528d82013-04-22 16:14:41 +0200716 return 0;
717}
718EXPORT_SYMBOL(rate_control_set_rates);
719
Johannes Bergff688082007-07-27 15:43:23 +0200720int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
721 const char *name)
722{
Johannes Berg889cbb92012-01-17 10:33:29 +0100723 struct rate_control_ref *ref;
Johannes Bergff688082007-07-27 15:43:23 +0200724
725 ASSERT_RTNL();
Johannes Bergaf65cd962009-11-17 18:18:36 +0100726
Johannes Berg3b8d81e02009-06-17 17:43:56 +0200727 if (local->open_count)
Johannes Bergff688082007-07-27 15:43:23 +0200728 return -EBUSY;
729
Johannes Bergaf65cd962009-11-17 18:18:36 +0100730 if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) {
731 if (WARN_ON(!local->ops->set_rts_threshold))
732 return -EINVAL;
733 return 0;
734 }
735
Johannes Bergff688082007-07-27 15:43:23 +0200736 ref = rate_control_alloc(name, local);
737 if (!ref) {
Joe Perches0fb9a9e2010-08-20 16:25:38 -0700738 wiphy_warn(local->hw.wiphy,
739 "Failed to select rate control algorithm\n");
Johannes Bergff688082007-07-27 15:43:23 +0200740 return -ENOENT;
741 }
742
Johannes Berg889cbb92012-01-17 10:33:29 +0100743 WARN_ON(local->rate_ctrl);
Johannes Bergff688082007-07-27 15:43:23 +0200744 local->rate_ctrl = ref;
Johannes Bergff688082007-07-27 15:43:23 +0200745
Joe Perches0fb9a9e2010-08-20 16:25:38 -0700746 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n",
747 ref->ops->name);
Johannes Bergff688082007-07-27 15:43:23 +0200748
Johannes Bergff688082007-07-27 15:43:23 +0200749 return 0;
750}
751
752void rate_control_deinitialize(struct ieee80211_local *local)
753{
754 struct rate_control_ref *ref;
755
756 ref = local->rate_ctrl;
Johannes Bergaf65cd962009-11-17 18:18:36 +0100757
758 if (!ref)
759 return;
760
Johannes Bergff688082007-07-27 15:43:23 +0200761 local->rate_ctrl = NULL;
Johannes Berg889cbb92012-01-17 10:33:29 +0100762 rate_control_free(ref);
Johannes Bergff688082007-07-27 15:43:23 +0200763}
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100764