blob: 22b223f13c9fa22994eba6f68769a27b2cfe4eb3 [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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090013#include <linux/slab.h>
Paul Gortmaker3a9a2312011-05-27 09:12:25 -040014#include <linux/module.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;
21 struct rate_control_ops *ops;
22};
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
Jiri Bencf0706e82007-05-05 11:45:53 -070032int ieee80211_rate_control_register(struct rate_control_ops *ops)
33{
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
63void ieee80211_rate_control_unregister(struct rate_control_ops *ops)
64{
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
79static struct rate_control_ops *
80ieee80211_try_rate_control_ops_get(const char *name)
81{
82 struct rate_control_alg *alg;
83 struct rate_control_ops *ops = NULL;
84
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 Bergac71c692007-10-28 14:17:44 +010090 if (!strcmp(alg->ops->name, name))
Jiri Bencf0706e82007-05-05 11:45:53 -070091 if (try_module_get(alg->ops->module)) {
92 ops = alg->ops;
93 break;
94 }
95 }
96 mutex_unlock(&rate_ctrl_mutex);
97 return ops;
98}
99
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100100/* Get the rate control algorithm. */
Jiri Bencf0706e82007-05-05 11:45:53 -0700101static struct rate_control_ops *
102ieee80211_rate_control_ops_get(const char *name)
103{
104 struct rate_control_ops *ops;
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100105 const char *alg_name;
Jiri Bencf0706e82007-05-05 11:45:53 -0700106
Rusty Russelld6d1b652010-08-11 23:04:27 -0600107 kparam_block_sysfs_write(ieee80211_default_rc_algo);
Johannes Bergac71c692007-10-28 14:17:44 +0100108 if (!name)
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100109 alg_name = ieee80211_default_rc_algo;
110 else
111 alg_name = name;
Johannes Bergac71c692007-10-28 14:17:44 +0100112
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100113 ops = ieee80211_try_rate_control_ops_get(alg_name);
Jiri Bencf0706e82007-05-05 11:45:53 -0700114 if (!ops) {
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100115 request_module("rc80211_%s", alg_name);
116 ops = ieee80211_try_rate_control_ops_get(alg_name);
Jiri Bencf0706e82007-05-05 11:45:53 -0700117 }
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100118 if (!ops && name)
119 /* try default if specific alg requested but not found */
120 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);
121
Johannes Berg4b475892008-01-02 15:17:03 +0100122 /* try built-in one if specific alg requested but not found */
123 if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT))
124 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
Rusty Russelld6d1b652010-08-11 23:04:27 -0600125 kparam_unblock_sysfs_write(ieee80211_default_rc_algo);
Johannes Berg4b475892008-01-02 15:17:03 +0100126
Jiri Bencf0706e82007-05-05 11:45:53 -0700127 return ops;
128}
129
130static void ieee80211_rate_control_ops_put(struct rate_control_ops *ops)
131{
132 module_put(ops->module);
133}
134
Johannes Berg4b7679a2008-09-18 18:14:18 +0200135#ifdef CONFIG_MAC80211_DEBUGFS
136static ssize_t rcname_read(struct file *file, char __user *userbuf,
137 size_t count, loff_t *ppos)
138{
139 struct rate_control_ref *ref = file->private_data;
140 int len = strlen(ref->ops->name);
141
142 return simple_read_from_buffer(userbuf, count, ppos,
143 ref->ops->name, len);
144}
145
146static const struct file_operations rcname_ops = {
147 .read = rcname_read,
Stephen Boyd234e3402012-04-05 14:25:11 -0700148 .open = simple_open,
Arnd Bergmann6038f372010-08-15 18:52:59 +0200149 .llseek = default_llseek,
Johannes Berg4b7679a2008-09-18 18:14:18 +0200150};
151#endif
152
Andres Salomon209c6712010-02-07 21:47:50 -0500153static struct rate_control_ref *rate_control_alloc(const char *name,
Jiri Bencf0706e82007-05-05 11:45:53 -0700154 struct ieee80211_local *local)
155{
Johannes Berg4b7679a2008-09-18 18:14:18 +0200156 struct dentry *debugfsdir = NULL;
Jiri Bencf0706e82007-05-05 11:45:53 -0700157 struct rate_control_ref *ref;
158
159 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
160 if (!ref)
161 goto fail_ref;
Johannes Berg4b7679a2008-09-18 18:14:18 +0200162 ref->local = local;
Jiri Bencf0706e82007-05-05 11:45:53 -0700163 ref->ops = ieee80211_rate_control_ops_get(name);
164 if (!ref->ops)
165 goto fail_ops;
Johannes Berg4b7679a2008-09-18 18:14:18 +0200166
167#ifdef CONFIG_MAC80211_DEBUGFS
168 debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir);
169 local->debugfs.rcdir = debugfsdir;
Johannes Berg7bcfaf22009-10-27 12:59:03 +0100170 debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops);
Johannes Berg4b7679a2008-09-18 18:14:18 +0200171#endif
172
173 ref->priv = ref->ops->alloc(&local->hw, debugfsdir);
Jiri Bencf0706e82007-05-05 11:45:53 -0700174 if (!ref->priv)
175 goto fail_priv;
176 return ref;
177
178fail_priv:
179 ieee80211_rate_control_ops_put(ref->ops);
180fail_ops:
181 kfree(ref);
182fail_ref:
183 return NULL;
184}
185
Johannes Berg889cbb92012-01-17 10:33:29 +0100186static void rate_control_free(struct rate_control_ref *ctrl_ref)
Jiri Bencf0706e82007-05-05 11:45:53 -0700187{
Jiri Bencf0706e82007-05-05 11:45:53 -0700188 ctrl_ref->ops->free(ctrl_ref->priv);
Johannes Berg4b7679a2008-09-18 18:14:18 +0200189
190#ifdef CONFIG_MAC80211_DEBUGFS
Johannes Berg7bcfaf22009-10-27 12:59:03 +0100191 debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir);
Johannes Berg4b7679a2008-09-18 18:14:18 +0200192 ctrl_ref->local->debugfs.rcdir = NULL;
193#endif
194
Jiri Bencf0706e82007-05-05 11:45:53 -0700195 ieee80211_rate_control_ops_put(ctrl_ref->ops);
196 kfree(ctrl_ref);
197}
198
Rajkumar Manoharanb6f35302011-09-29 20:34:04 +0530199static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc)
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700200{
201 struct sk_buff *skb = txrc->skb;
202 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
203 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
204 __le16 fc;
205
206 fc = hdr->frame_control;
207
Rajkumar Manoharanb6f35302011-09-29 20:34:04 +0530208 return (info->flags & (IEEE80211_TX_CTL_NO_ACK |
209 IEEE80211_TX_CTL_USE_MINRATE)) ||
210 !ieee80211_is_data(fc);
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700211}
212
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700213static void rc_send_low_basicrate(s8 *idx, u32 basic_rates,
Felix Fietkau8f0729b2010-11-11 15:07:23 +0100214 struct ieee80211_supported_band *sband)
Jouni Malinene00cfce2009-12-29 12:59:19 +0200215{
216 u8 i;
217
218 if (basic_rates == 0)
219 return; /* assume basic rates unknown and accept rate */
220 if (*idx < 0)
221 return;
222 if (basic_rates & (1 << *idx))
223 return; /* selected rate is a basic rate */
224
Felix Fietkau8f0729b2010-11-11 15:07:23 +0100225 for (i = *idx + 1; i <= sband->n_bitrates; i++) {
Jouni Malinene00cfce2009-12-29 12:59:19 +0200226 if (basic_rates & (1 << i)) {
227 *idx = i;
228 return;
229 }
230 }
231
232 /* could not find a basic rate; use original selection */
233}
234
Felix Fietkau0d528d82013-04-22 16:14:41 +0200235static void __rate_control_send_low(struct ieee80211_hw *hw,
236 struct ieee80211_supported_band *sband,
237 struct ieee80211_sta *sta,
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200238 struct ieee80211_tx_info *info,
239 u32 rate_mask)
Felix Fietkau0d528d82013-04-22 16:14:41 +0200240{
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200241 int i;
242 u32 rate_flags =
243 ieee80211_chandef_rate_flags(&hw->conf.chandef);
244
245 if ((sband->band == IEEE80211_BAND_2GHZ) &&
246 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
247 rate_flags |= IEEE80211_RATE_ERP_G;
248
249 info->control.rates[0].idx = 0;
250 for (i = 0; i < sband->n_bitrates; i++) {
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200251 if (!(rate_mask & BIT(i)))
252 continue;
253
Andrei Otcheretianski1431fcb2013-10-14 10:46:55 +0200254 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
255 continue;
256
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200257 if (!rate_supported(sta, sband->band, i))
258 continue;
259
260 info->control.rates[0].idx = i;
261 break;
262 }
263 WARN_ON_ONCE(i == sband->n_bitrates);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200264
265 info->control.rates[0].count =
266 (info->flags & IEEE80211_TX_CTL_NO_ACK) ?
267 1 : hw->max_rate_tries;
268
269 info->control.skip_table = 1;
270}
271
Rajkumar Manoharanaad14ce2011-09-25 14:53:31 +0530272
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700273bool rate_control_send_low(struct ieee80211_sta *pubsta,
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700274 void *priv_sta,
275 struct ieee80211_tx_rate_control *txrc)
276{
277 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100278 struct ieee80211_supported_band *sband = txrc->sband;
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700279 struct sta_info *sta;
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100280 int mcast_rate;
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700281 bool use_basicrate = false;
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700282
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700283 if (!pubsta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) {
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200284 __rate_control_send_low(txrc->hw, sband, pubsta, info,
285 txrc->rate_idx_mask);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200286
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700287 if (!pubsta && txrc->bss) {
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100288 mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
289 if (mcast_rate > 0) {
290 info->control.rates[0].idx = mcast_rate - 1;
291 return true;
292 }
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700293 use_basicrate = true;
294 } else if (pubsta) {
295 sta = container_of(pubsta, struct sta_info, sta);
296 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
297 use_basicrate = true;
298 }
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100299
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700300 if (use_basicrate)
301 rc_send_low_basicrate(&info->control.rates[0].idx,
Jouni Malinene00cfce2009-12-29 12:59:19 +0200302 txrc->bss_conf->basic_rates,
Felix Fietkaudd5b4cc2010-11-22 20:58:24 +0100303 sband);
Chun-Yeow Yeoh06703072013-08-06 15:39:56 -0700304
Luis R. Rodriguez4c6d4f52009-07-16 10:05:41 -0700305 return true;
306 }
307 return false;
308}
309EXPORT_SYMBOL(rate_control_send_low);
310
Simon Wunderlich19468412012-01-28 17:25:33 +0100311static bool rate_idx_match_legacy_mask(struct ieee80211_tx_rate *rate,
312 int n_bitrates, u32 mask)
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200313{
314 int j;
315
316 /* See whether the selected rate or anything below it is allowed. */
317 for (j = rate->idx; j >= 0; j--) {
318 if (mask & (1 << j)) {
319 /* Okay, found a suitable rate. Use it. */
320 rate->idx = j;
Simon Wunderlich19468412012-01-28 17:25:33 +0100321 return true;
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200322 }
323 }
324
325 /* Try to find a higher rate that would be allowed */
326 for (j = rate->idx + 1; j < n_bitrates; j++) {
327 if (mask & (1 << j)) {
328 /* Okay, found a suitable rate. Use it. */
329 rate->idx = j;
Simon Wunderlich19468412012-01-28 17:25:33 +0100330 return true;
331 }
332 }
333 return false;
334}
335
336static bool rate_idx_match_mcs_mask(struct ieee80211_tx_rate *rate,
337 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
338{
339 int i, j;
340 int ridx, rbit;
341
342 ridx = rate->idx / 8;
343 rbit = rate->idx % 8;
344
345 /* sanity check */
Dan Carpenter910570b52012-02-01 10:42:11 +0300346 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN)
Simon Wunderlich19468412012-01-28 17:25:33 +0100347 return false;
348
349 /* See whether the selected rate or anything below it is allowed. */
350 for (i = ridx; i >= 0; i--) {
351 for (j = rbit; j >= 0; j--)
352 if (mcs_mask[i] & BIT(j)) {
353 rate->idx = i * 8 + j;
354 return true;
355 }
356 rbit = 7;
357 }
358
359 /* Try to find a higher rate that would be allowed */
360 ridx = (rate->idx + 1) / 8;
361 rbit = (rate->idx + 1) % 8;
362
363 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
364 for (j = rbit; j < 8; j++)
365 if (mcs_mask[i] & BIT(j)) {
366 rate->idx = i * 8 + j;
367 return true;
368 }
369 rbit = 0;
370 }
371 return false;
372}
373
374
375
376static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
Felix Fietkau0d528d82013-04-22 16:14:41 +0200377 struct ieee80211_supported_band *sband,
378 enum nl80211_chan_width chan_width,
Simon Wunderlich19468412012-01-28 17:25:33 +0100379 u32 mask,
380 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
381{
382 struct ieee80211_tx_rate alt_rate;
383
384 /* handle HT rates */
385 if (rate->flags & IEEE80211_TX_RC_MCS) {
386 if (rate_idx_match_mcs_mask(rate, mcs_mask))
387 return;
388
389 /* also try the legacy rates. */
390 alt_rate.idx = 0;
391 /* keep protection flags */
392 alt_rate.flags = rate->flags &
393 (IEEE80211_TX_RC_USE_RTS_CTS |
394 IEEE80211_TX_RC_USE_CTS_PROTECT |
395 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
396 alt_rate.count = rate->count;
397 if (rate_idx_match_legacy_mask(&alt_rate,
Felix Fietkau0d528d82013-04-22 16:14:41 +0200398 sband->n_bitrates, mask)) {
Simon Wunderlich19468412012-01-28 17:25:33 +0100399 *rate = alt_rate;
400 return;
401 }
402 } else {
Simon Wunderlich19468412012-01-28 17:25:33 +0100403 /* handle legacy rates */
Felix Fietkau0d528d82013-04-22 16:14:41 +0200404 if (rate_idx_match_legacy_mask(rate, sband->n_bitrates, mask))
Simon Wunderlich19468412012-01-28 17:25:33 +0100405 return;
406
407 /* if HT BSS, and we handle a data frame, also try HT rates */
Simon Wunderlich0418a442013-05-16 13:00:31 +0200408 switch (chan_width) {
409 case NL80211_CHAN_WIDTH_20_NOHT:
410 case NL80211_CHAN_WIDTH_5:
411 case NL80211_CHAN_WIDTH_10:
Simon Wunderlich19468412012-01-28 17:25:33 +0100412 return;
Simon Wunderlich0418a442013-05-16 13:00:31 +0200413 default:
414 break;
415 }
Simon Wunderlich19468412012-01-28 17:25:33 +0100416
417 alt_rate.idx = 0;
418 /* keep protection flags */
419 alt_rate.flags = rate->flags &
420 (IEEE80211_TX_RC_USE_RTS_CTS |
421 IEEE80211_TX_RC_USE_CTS_PROTECT |
422 IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
423 alt_rate.count = rate->count;
424
425 alt_rate.flags |= IEEE80211_TX_RC_MCS;
426
Felix Fietkau0d528d82013-04-22 16:14:41 +0200427 if (chan_width == NL80211_CHAN_WIDTH_40)
Simon Wunderlich19468412012-01-28 17:25:33 +0100428 alt_rate.flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
429
430 if (rate_idx_match_mcs_mask(&alt_rate, mcs_mask)) {
431 *rate = alt_rate;
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200432 return;
433 }
434 }
435
436 /*
437 * Uh.. No suitable rate exists. This should not really happen with
438 * sane TX rate mask configurations. However, should someone manage to
439 * configure supported rates and TX rate mask in incompatible way,
440 * allow the frame to be transmitted with whatever the rate control
441 * selected.
442 */
443}
444
Felix Fietkau0d528d82013-04-22 16:14:41 +0200445static void rate_fixup_ratelist(struct ieee80211_vif *vif,
446 struct ieee80211_supported_band *sband,
447 struct ieee80211_tx_info *info,
448 struct ieee80211_tx_rate *rates,
449 int max_rates)
450{
451 struct ieee80211_rate *rate;
452 bool inval = false;
453 int i;
454
455 /*
456 * Set up the RTS/CTS rate as the fastest basic rate
457 * that is not faster than the data rate unless there
458 * is no basic rate slower than the data rate, in which
459 * case we pick the slowest basic rate
460 *
461 * XXX: Should this check all retry rates?
462 */
463 if (!(rates[0].flags & IEEE80211_TX_RC_MCS)) {
464 u32 basic_rates = vif->bss_conf.basic_rates;
465 s8 baserate = basic_rates ? ffs(basic_rates - 1) : 0;
466
467 rate = &sband->bitrates[rates[0].idx];
468
469 for (i = 0; i < sband->n_bitrates; i++) {
470 /* must be a basic rate */
471 if (!(basic_rates & BIT(i)))
472 continue;
473 /* must not be faster than the data rate */
474 if (sband->bitrates[i].bitrate > rate->bitrate)
475 continue;
476 /* maximum */
477 if (sband->bitrates[baserate].bitrate <
478 sband->bitrates[i].bitrate)
479 baserate = i;
480 }
481
482 info->control.rts_cts_rate_idx = baserate;
483 }
484
485 for (i = 0; i < max_rates; i++) {
486 /*
487 * make sure there's no valid rate following
488 * an invalid one, just in case drivers don't
489 * take the API seriously to stop at -1.
490 */
491 if (inval) {
492 rates[i].idx = -1;
493 continue;
494 }
495 if (rates[i].idx < 0) {
496 inval = true;
497 continue;
498 }
499
500 /*
501 * For now assume MCS is already set up correctly, this
502 * needs to be fixed.
503 */
504 if (rates[i].flags & IEEE80211_TX_RC_MCS) {
505 WARN_ON(rates[i].idx > 76);
506
507 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
508 info->control.use_cts_prot)
509 rates[i].flags |=
510 IEEE80211_TX_RC_USE_CTS_PROTECT;
511 continue;
512 }
513
514 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) {
515 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9);
516 continue;
517 }
518
519 /* set up RTS protection if desired */
520 if (info->control.use_rts) {
521 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS;
522 info->control.use_cts_prot = false;
523 }
524
525 /* RC is busted */
526 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) {
527 rates[i].idx = -1;
528 continue;
529 }
530
531 rate = &sband->bitrates[rates[i].idx];
532
533 /* set up short preamble */
534 if (info->control.short_preamble &&
535 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
536 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
537
538 /* set up G protection */
539 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
540 info->control.use_cts_prot &&
541 rate->flags & IEEE80211_RATE_ERP_G)
542 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
543 }
544}
545
546
547static void rate_control_fill_sta_table(struct ieee80211_sta *sta,
548 struct ieee80211_tx_info *info,
549 struct ieee80211_tx_rate *rates,
550 int max_rates)
551{
552 struct ieee80211_sta_rates *ratetbl = NULL;
553 int i;
554
555 if (sta && !info->control.skip_table)
556 ratetbl = rcu_dereference(sta->rates);
557
558 /* Fill remaining rate slots with data from the sta rate table. */
559 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE);
560 for (i = 0; i < max_rates; i++) {
561 if (i < ARRAY_SIZE(info->control.rates) &&
562 info->control.rates[i].idx >= 0 &&
563 info->control.rates[i].count) {
564 if (rates != info->control.rates)
565 rates[i] = info->control.rates[i];
566 } else if (ratetbl) {
567 rates[i].idx = ratetbl->rate[i].idx;
568 rates[i].flags = ratetbl->rate[i].flags;
569 if (info->control.use_rts)
570 rates[i].count = ratetbl->rate[i].count_rts;
571 else if (info->control.use_cts_prot)
572 rates[i].count = ratetbl->rate[i].count_cts;
573 else
574 rates[i].count = ratetbl->rate[i].count;
575 } else {
576 rates[i].idx = -1;
577 rates[i].count = 0;
578 }
579
580 if (rates[i].idx < 0 || !rates[i].count)
581 break;
582 }
583}
584
585static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata,
586 struct ieee80211_sta *sta,
587 struct ieee80211_supported_band *sband,
588 struct ieee80211_tx_info *info,
589 struct ieee80211_tx_rate *rates,
590 int max_rates)
591{
592 enum nl80211_chan_width chan_width;
593 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
594 bool has_mcs_mask;
595 u32 mask;
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200596 u32 rate_flags;
Felix Fietkau0d528d82013-04-22 16:14:41 +0200597 int i;
598
599 /*
600 * Try to enforce the rateidx mask the user wanted. skip this if the
601 * default mask (allow all rates) is used to save some processing for
602 * the common case.
603 */
604 mask = sdata->rc_rateidx_mask[info->band];
605 has_mcs_mask = sdata->rc_has_mcs_mask[info->band];
Simon Wunderlich2103dec2013-07-08 16:55:53 +0200606 rate_flags =
607 ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef);
608 for (i = 0; i < sband->n_bitrates; i++)
609 if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
610 mask &= ~BIT(i);
611
Felix Fietkau0d528d82013-04-22 16:14:41 +0200612 if (mask == (1 << sband->n_bitrates) - 1 && !has_mcs_mask)
613 return;
614
615 if (has_mcs_mask)
616 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[info->band],
617 sizeof(mcs_mask));
618 else
619 memset(mcs_mask, 0xff, sizeof(mcs_mask));
620
621 if (sta) {
622 /* Filter out rates that the STA does not support */
623 mask &= sta->supp_rates[info->band];
624 for (i = 0; i < sizeof(mcs_mask); i++)
625 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i];
626 }
627
628 /*
629 * Make sure the rate index selected for each TX rate is
630 * included in the configured mask and change the rate indexes
631 * if needed.
632 */
633 chan_width = sdata->vif.bss_conf.chandef.width;
634 for (i = 0; i < max_rates; i++) {
635 /* Skip invalid rates */
636 if (rates[i].idx < 0)
637 break;
638
Simon Wunderlich795d8552013-06-11 10:44:40 +0200639 rate_idx_match_mask(&rates[i], sband, chan_width, mask,
Felix Fietkau0d528d82013-04-22 16:14:41 +0200640 mcs_mask);
641 }
642}
643
644void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
645 struct ieee80211_sta *sta,
646 struct sk_buff *skb,
647 struct ieee80211_tx_rate *dest,
648 int max_rates)
649{
650 struct ieee80211_sub_if_data *sdata;
651 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
652 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
653 struct ieee80211_supported_band *sband;
654
655 rate_control_fill_sta_table(sta, info, dest, max_rates);
656
657 if (!vif)
658 return;
659
660 sdata = vif_to_sdata(vif);
661 sband = sdata->local->hw.wiphy->bands[info->band];
662
663 if (ieee80211_is_data(hdr->frame_control))
664 rate_control_apply_mask(sdata, sta, sband, info, dest, max_rates);
665
666 if (dest[0].idx < 0)
Andrei Otcheretianski1d2d3502013-10-14 11:04:28 +0200667 __rate_control_send_low(&sdata->local->hw, sband, sta, info,
668 sdata->rc_rateidx_mask[info->band]);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200669
670 if (sta)
671 rate_fixup_ratelist(vif, sband, info, dest, max_rates);
672}
673EXPORT_SYMBOL(ieee80211_get_tx_rates);
674
Johannes Berg4b7679a2008-09-18 18:14:18 +0200675void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
Johannes Berge6a98542008-10-21 12:40:02 +0200676 struct sta_info *sta,
677 struct ieee80211_tx_rate_control *txrc)
Mattias Nissler1abbe492007-12-20 13:50:07 +0100678{
Johannes Berg4b7679a2008-09-18 18:14:18 +0200679 struct rate_control_ref *ref = sdata->local->rate_ctrl;
680 void *priv_sta = NULL;
681 struct ieee80211_sta *ista = NULL;
Johannes Berge6a98542008-10-21 12:40:02 +0200682 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
Mattias Nissler1abbe492007-12-20 13:50:07 +0100683 int i;
Mattias Nissler1abbe492007-12-20 13:50:07 +0100684
Johannes Berge1936e92012-01-20 13:55:23 +0100685 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) {
Johannes Berg4b7679a2008-09-18 18:14:18 +0200686 ista = &sta->sta;
687 priv_sta = sta->rate_ctrl_priv;
688 }
689
Johannes Berge6a98542008-10-21 12:40:02 +0200690 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
691 info->control.rates[i].idx = -1;
692 info->control.rates[i].flags = 0;
Mohammed Shafi Shajakhan8617b092012-02-20 10:05:31 +0530693 info->control.rates[i].count = 0;
Mattias Nissler1abbe492007-12-20 13:50:07 +0100694 }
Johannes Berge6a98542008-10-21 12:40:02 +0200695
Juuso Oikarinen5affcd62010-02-12 10:05:45 +0200696 if (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
697 return;
698
Jouni Malinen37eb0b12010-01-06 13:09:08 +0200699 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
Johannes Berge6a98542008-10-21 12:40:02 +0200700
Felix Fietkau0d528d82013-04-22 16:14:41 +0200701 if (sdata->local->hw.flags & IEEE80211_HW_SUPPORTS_RC_TABLE)
702 return;
Felix Fietkau2ffbe6d2013-04-16 13:38:42 +0200703
Felix Fietkau0d528d82013-04-22 16:14:41 +0200704 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb,
705 info->control.rates,
706 ARRAY_SIZE(info->control.rates));
Mattias Nissler1abbe492007-12-20 13:50:07 +0100707}
708
Felix Fietkau0d528d82013-04-22 16:14:41 +0200709int rate_control_set_rates(struct ieee80211_hw *hw,
710 struct ieee80211_sta *pubsta,
711 struct ieee80211_sta_rates *rates)
712{
Felix Fietkauf6b3d852013-05-03 10:01:03 +0200713 struct ieee80211_sta_rates *old;
Felix Fietkau0d528d82013-04-22 16:14:41 +0200714
Felix Fietkauf6b3d852013-05-03 10:01:03 +0200715 /*
716 * mac80211 guarantees that this function will not be called
717 * concurrently, so the following RCU access is safe, even without
718 * extra locking. This can not be checked easily, so we just set
719 * the condition to true.
720 */
721 old = rcu_dereference_protected(pubsta->rates, true);
Felix Fietkau0d528d82013-04-22 16:14:41 +0200722 rcu_assign_pointer(pubsta->rates, rates);
723 if (old)
724 kfree_rcu(old, rcu_head);
725
726 return 0;
727}
728EXPORT_SYMBOL(rate_control_set_rates);
729
Johannes Bergff688082007-07-27 15:43:23 +0200730int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
731 const char *name)
732{
Johannes Berg889cbb92012-01-17 10:33:29 +0100733 struct rate_control_ref *ref;
Johannes Bergff688082007-07-27 15:43:23 +0200734
735 ASSERT_RTNL();
Johannes Bergaf65cd962009-11-17 18:18:36 +0100736
Johannes Berg3b8d81e02009-06-17 17:43:56 +0200737 if (local->open_count)
Johannes Bergff688082007-07-27 15:43:23 +0200738 return -EBUSY;
739
Johannes Bergaf65cd962009-11-17 18:18:36 +0100740 if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) {
741 if (WARN_ON(!local->ops->set_rts_threshold))
742 return -EINVAL;
743 return 0;
744 }
745
Johannes Bergff688082007-07-27 15:43:23 +0200746 ref = rate_control_alloc(name, local);
747 if (!ref) {
Joe Perches0fb9a9e2010-08-20 16:25:38 -0700748 wiphy_warn(local->hw.wiphy,
749 "Failed to select rate control algorithm\n");
Johannes Bergff688082007-07-27 15:43:23 +0200750 return -ENOENT;
751 }
752
Johannes Berg889cbb92012-01-17 10:33:29 +0100753 WARN_ON(local->rate_ctrl);
Johannes Bergff688082007-07-27 15:43:23 +0200754 local->rate_ctrl = ref;
Johannes Bergff688082007-07-27 15:43:23 +0200755
Joe Perches0fb9a9e2010-08-20 16:25:38 -0700756 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n",
757 ref->ops->name);
Johannes Bergff688082007-07-27 15:43:23 +0200758
Johannes Bergff688082007-07-27 15:43:23 +0200759 return 0;
760}
761
762void rate_control_deinitialize(struct ieee80211_local *local)
763{
764 struct rate_control_ref *ref;
765
766 ref = local->rate_ctrl;
Johannes Bergaf65cd962009-11-17 18:18:36 +0100767
768 if (!ref)
769 return;
770
Johannes Bergff688082007-07-27 15:43:23 +0200771 local->rate_ctrl = NULL;
Johannes Berg889cbb92012-01-17 10:33:29 +0100772 rate_control_free(ref);
Johannes Bergff688082007-07-27 15:43:23 +0200773}
Stefano Brivioc21b39a2007-12-19 01:26:16 +0100774