]>
Commit | Line | Data |
---|---|---|
f0706e82 JB |
1 | /* |
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> | |
ff688089 | 12 | #include <linux/rtnetlink.h> |
5a0e3ad6 | 13 | #include <linux/slab.h> |
3a9a231d | 14 | #include <linux/module.h> |
2c8dccc7 | 15 | #include "rate.h" |
f0706e82 | 16 | #include "ieee80211_i.h" |
4b7679a5 | 17 | #include "debugfs.h" |
f0706e82 JB |
18 | |
19 | struct rate_control_alg { | |
20 | struct list_head list; | |
21 | struct rate_control_ops *ops; | |
22 | }; | |
23 | ||
24 | static LIST_HEAD(rate_ctrl_algs); | |
25 | static DEFINE_MUTEX(rate_ctrl_mutex); | |
26 | ||
c21b39ac SB |
27 | static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT; |
28 | module_param(ieee80211_default_rc_algo, charp, 0644); | |
29 | MODULE_PARM_DESC(ieee80211_default_rc_algo, | |
30 | "Default rate control algorithm for mac80211 to use"); | |
31 | ||
f0706e82 JB |
32 | int ieee80211_rate_control_register(struct rate_control_ops *ops) |
33 | { | |
34 | struct rate_control_alg *alg; | |
35 | ||
ac71c691 JB |
36 | if (!ops->name) |
37 | return -EINVAL; | |
38 | ||
999acd9c JB |
39 | 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); | |
b808ab16 | 44 | mutex_unlock(&rate_ctrl_mutex); |
999acd9c JB |
45 | return -EALREADY; |
46 | } | |
47 | } | |
48 | ||
dd00cc48 | 49 | alg = kzalloc(sizeof(*alg), GFP_KERNEL); |
f0706e82 | 50 | if (alg == NULL) { |
999acd9c | 51 | mutex_unlock(&rate_ctrl_mutex); |
f0706e82 JB |
52 | return -ENOMEM; |
53 | } | |
f0706e82 JB |
54 | alg->ops = ops; |
55 | ||
f0706e82 JB |
56 | list_add_tail(&alg->list, &rate_ctrl_algs); |
57 | mutex_unlock(&rate_ctrl_mutex); | |
58 | ||
59 | return 0; | |
60 | } | |
61 | EXPORT_SYMBOL(ieee80211_rate_control_register); | |
62 | ||
63 | void 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); | |
20880e89 | 71 | kfree(alg); |
f0706e82 JB |
72 | break; |
73 | } | |
74 | } | |
75 | mutex_unlock(&rate_ctrl_mutex); | |
f0706e82 JB |
76 | } |
77 | EXPORT_SYMBOL(ieee80211_rate_control_unregister); | |
78 | ||
79 | static struct rate_control_ops * | |
80 | ieee80211_try_rate_control_ops_get(const char *name) | |
81 | { | |
82 | struct rate_control_alg *alg; | |
83 | struct rate_control_ops *ops = NULL; | |
84 | ||
ac71c691 JB |
85 | if (!name) |
86 | return NULL; | |
87 | ||
f0706e82 JB |
88 | mutex_lock(&rate_ctrl_mutex); |
89 | list_for_each_entry(alg, &rate_ctrl_algs, list) { | |
ac71c691 | 90 | if (!strcmp(alg->ops->name, name)) |
f0706e82 JB |
91 | 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 | ||
c21b39ac | 100 | /* Get the rate control algorithm. */ |
f0706e82 JB |
101 | static struct rate_control_ops * |
102 | ieee80211_rate_control_ops_get(const char *name) | |
103 | { | |
104 | struct rate_control_ops *ops; | |
c21b39ac | 105 | const char *alg_name; |
f0706e82 | 106 | |
d6d1b650 | 107 | kparam_block_sysfs_write(ieee80211_default_rc_algo); |
ac71c691 | 108 | if (!name) |
c21b39ac SB |
109 | alg_name = ieee80211_default_rc_algo; |
110 | else | |
111 | alg_name = name; | |
ac71c691 | 112 | |
c21b39ac | 113 | ops = ieee80211_try_rate_control_ops_get(alg_name); |
f0706e82 | 114 | if (!ops) { |
c21b39ac SB |
115 | request_module("rc80211_%s", alg_name); |
116 | ops = ieee80211_try_rate_control_ops_get(alg_name); | |
f0706e82 | 117 | } |
c21b39ac SB |
118 | 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 | ||
4b475898 JB |
122 | /* 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); | |
d6d1b650 | 125 | kparam_unblock_sysfs_write(ieee80211_default_rc_algo); |
4b475898 | 126 | |
f0706e82 JB |
127 | return ops; |
128 | } | |
129 | ||
130 | static void ieee80211_rate_control_ops_put(struct rate_control_ops *ops) | |
131 | { | |
132 | module_put(ops->module); | |
133 | } | |
134 | ||
4b7679a5 JB |
135 | #ifdef CONFIG_MAC80211_DEBUGFS |
136 | static 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 | ||
146 | static const struct file_operations rcname_ops = { | |
147 | .read = rcname_read, | |
148 | .open = mac80211_open_file_generic, | |
6038f373 | 149 | .llseek = default_llseek, |
4b7679a5 JB |
150 | }; |
151 | #endif | |
152 | ||
209c671d | 153 | static struct rate_control_ref *rate_control_alloc(const char *name, |
f0706e82 JB |
154 | struct ieee80211_local *local) |
155 | { | |
4b7679a5 | 156 | struct dentry *debugfsdir = NULL; |
f0706e82 JB |
157 | struct rate_control_ref *ref; |
158 | ||
159 | ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL); | |
160 | if (!ref) | |
161 | goto fail_ref; | |
4b7679a5 | 162 | ref->local = local; |
f0706e82 JB |
163 | ref->ops = ieee80211_rate_control_ops_get(name); |
164 | if (!ref->ops) | |
165 | goto fail_ops; | |
4b7679a5 JB |
166 | |
167 | #ifdef CONFIG_MAC80211_DEBUGFS | |
168 | debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir); | |
169 | local->debugfs.rcdir = debugfsdir; | |
7bcfaf2f | 170 | debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops); |
4b7679a5 JB |
171 | #endif |
172 | ||
173 | ref->priv = ref->ops->alloc(&local->hw, debugfsdir); | |
f0706e82 JB |
174 | if (!ref->priv) |
175 | goto fail_priv; | |
176 | return ref; | |
177 | ||
178 | fail_priv: | |
179 | ieee80211_rate_control_ops_put(ref->ops); | |
180 | fail_ops: | |
181 | kfree(ref); | |
182 | fail_ref: | |
183 | return NULL; | |
184 | } | |
185 | ||
889cbb91 | 186 | static void rate_control_free(struct rate_control_ref *ctrl_ref) |
f0706e82 | 187 | { |
f0706e82 | 188 | ctrl_ref->ops->free(ctrl_ref->priv); |
4b7679a5 JB |
189 | |
190 | #ifdef CONFIG_MAC80211_DEBUGFS | |
7bcfaf2f | 191 | debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir); |
4b7679a5 JB |
192 | ctrl_ref->local->debugfs.rcdir = NULL; |
193 | #endif | |
194 | ||
f0706e82 JB |
195 | ieee80211_rate_control_ops_put(ctrl_ref->ops); |
196 | kfree(ctrl_ref); | |
197 | } | |
198 | ||
b6f35301 | 199 | static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc) |
4c6d4f5c LR |
200 | { |
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 | ||
b6f35301 RM |
208 | return (info->flags & (IEEE80211_TX_CTL_NO_ACK | |
209 | IEEE80211_TX_CTL_USE_MINRATE)) || | |
210 | !ieee80211_is_data(fc); | |
4c6d4f5c LR |
211 | } |
212 | ||
dd5b4cc7 | 213 | static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, |
8f0729b1 | 214 | struct ieee80211_supported_band *sband) |
e00cfce0 JM |
215 | { |
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 | ||
8f0729b1 | 225 | for (i = *idx + 1; i <= sband->n_bitrates; i++) { |
e00cfce0 JM |
226 | 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 | ||
aad14ceb RM |
235 | static inline s8 |
236 | rate_lowest_non_cck_index(struct ieee80211_supported_band *sband, | |
237 | struct ieee80211_sta *sta) | |
238 | { | |
239 | int i; | |
240 | ||
241 | for (i = 0; i < sband->n_bitrates; i++) { | |
242 | struct ieee80211_rate *srate = &sband->bitrates[i]; | |
243 | if ((srate->bitrate == 10) || (srate->bitrate == 20) || | |
244 | (srate->bitrate == 55) || (srate->bitrate == 110)) | |
245 | continue; | |
246 | ||
247 | if (rate_supported(sta, sband->band, i)) | |
248 | return i; | |
249 | } | |
250 | ||
251 | /* No matching rate found */ | |
252 | return 0; | |
253 | } | |
254 | ||
255 | ||
4c6d4f5c LR |
256 | bool rate_control_send_low(struct ieee80211_sta *sta, |
257 | void *priv_sta, | |
258 | struct ieee80211_tx_rate_control *txrc) | |
259 | { | |
260 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); | |
dd5b4cc7 FF |
261 | struct ieee80211_supported_band *sband = txrc->sband; |
262 | int mcast_rate; | |
4c6d4f5c | 263 | |
b6f35301 | 264 | if (!sta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) { |
aad14ceb RM |
265 | if ((sband->band != IEEE80211_BAND_2GHZ) || |
266 | !(info->flags & IEEE80211_TX_CTL_NO_CCK_RATE)) | |
267 | info->control.rates[0].idx = | |
268 | rate_lowest_index(txrc->sband, sta); | |
269 | else | |
270 | info->control.rates[0].idx = | |
271 | rate_lowest_non_cck_index(txrc->sband, sta); | |
4c6d4f5c LR |
272 | info->control.rates[0].count = |
273 | (info->flags & IEEE80211_TX_CTL_NO_ACK) ? | |
274 | 1 : txrc->hw->max_rate_tries; | |
dd5b4cc7 FF |
275 | if (!sta && txrc->bss) { |
276 | mcast_rate = txrc->bss_conf->mcast_rate[sband->band]; | |
277 | if (mcast_rate > 0) { | |
278 | info->control.rates[0].idx = mcast_rate - 1; | |
279 | return true; | |
280 | } | |
281 | ||
e00cfce0 JM |
282 | rc_send_low_broadcast(&info->control.rates[0].idx, |
283 | txrc->bss_conf->basic_rates, | |
dd5b4cc7 FF |
284 | sband); |
285 | } | |
4c6d4f5c LR |
286 | return true; |
287 | } | |
288 | return false; | |
289 | } | |
290 | EXPORT_SYMBOL(rate_control_send_low); | |
291 | ||
37eb0b16 JM |
292 | static void rate_idx_match_mask(struct ieee80211_tx_rate *rate, |
293 | int n_bitrates, u32 mask) | |
294 | { | |
295 | int j; | |
296 | ||
297 | /* See whether the selected rate or anything below it is allowed. */ | |
298 | for (j = rate->idx; j >= 0; j--) { | |
299 | if (mask & (1 << j)) { | |
300 | /* Okay, found a suitable rate. Use it. */ | |
301 | rate->idx = j; | |
302 | return; | |
303 | } | |
304 | } | |
305 | ||
306 | /* Try to find a higher rate that would be allowed */ | |
307 | for (j = rate->idx + 1; j < n_bitrates; j++) { | |
308 | if (mask & (1 << j)) { | |
309 | /* Okay, found a suitable rate. Use it. */ | |
310 | rate->idx = j; | |
311 | return; | |
312 | } | |
313 | } | |
314 | ||
315 | /* | |
316 | * Uh.. No suitable rate exists. This should not really happen with | |
317 | * sane TX rate mask configurations. However, should someone manage to | |
318 | * configure supported rates and TX rate mask in incompatible way, | |
319 | * allow the frame to be transmitted with whatever the rate control | |
320 | * selected. | |
321 | */ | |
322 | } | |
323 | ||
4b7679a5 | 324 | void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, |
e6a9854b JB |
325 | struct sta_info *sta, |
326 | struct ieee80211_tx_rate_control *txrc) | |
1abbe498 | 327 | { |
4b7679a5 JB |
328 | struct rate_control_ref *ref = sdata->local->rate_ctrl; |
329 | void *priv_sta = NULL; | |
330 | struct ieee80211_sta *ista = NULL; | |
e6a9854b | 331 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); |
1abbe498 | 332 | int i; |
37eb0b16 | 333 | u32 mask; |
1abbe498 | 334 | |
4b7679a5 JB |
335 | if (sta) { |
336 | ista = &sta->sta; | |
337 | priv_sta = sta->rate_ctrl_priv; | |
338 | } | |
339 | ||
e6a9854b JB |
340 | for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { |
341 | info->control.rates[i].idx = -1; | |
342 | info->control.rates[i].flags = 0; | |
343 | info->control.rates[i].count = 1; | |
344 | } | |
345 | ||
5affcd6b JO |
346 | if (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) |
347 | return; | |
348 | ||
37eb0b16 | 349 | ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); |
e6a9854b JB |
350 | |
351 | /* | |
37eb0b16 JM |
352 | * Try to enforce the rateidx mask the user wanted. skip this if the |
353 | * default mask (allow all rates) is used to save some processing for | |
354 | * the common case. | |
e6a9854b | 355 | */ |
37eb0b16 JM |
356 | mask = sdata->rc_rateidx_mask[info->band]; |
357 | if (mask != (1 << txrc->sband->n_bitrates) - 1) { | |
358 | if (sta) { | |
359 | /* Filter out rates that the STA does not support */ | |
360 | mask &= sta->sta.supp_rates[info->band]; | |
361 | } | |
362 | /* | |
363 | * Make sure the rate index selected for each TX rate is | |
364 | * included in the configured mask and change the rate indexes | |
365 | * if needed. | |
366 | */ | |
e6a9854b | 367 | for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { |
5f4e6b2d CL |
368 | /* Skip invalid rates */ |
369 | if (info->control.rates[i].idx < 0) | |
370 | break; | |
37eb0b16 | 371 | /* Rate masking supports only legacy rates for now */ |
e6a9854b JB |
372 | if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) |
373 | continue; | |
37eb0b16 JM |
374 | rate_idx_match_mask(&info->control.rates[i], |
375 | txrc->sband->n_bitrates, mask); | |
376 | } | |
1abbe498 | 377 | } |
e6a9854b JB |
378 | |
379 | BUG_ON(info->control.rates[0].idx < 0); | |
1abbe498 MN |
380 | } |
381 | ||
ff688089 JB |
382 | int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, |
383 | const char *name) | |
384 | { | |
889cbb91 | 385 | struct rate_control_ref *ref; |
ff688089 JB |
386 | |
387 | ASSERT_RTNL(); | |
af65cd96 | 388 | |
3b8d81e0 | 389 | if (local->open_count) |
ff688089 JB |
390 | return -EBUSY; |
391 | ||
af65cd96 JB |
392 | if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) { |
393 | if (WARN_ON(!local->ops->set_rts_threshold)) | |
394 | return -EINVAL; | |
395 | return 0; | |
396 | } | |
397 | ||
ff688089 JB |
398 | ref = rate_control_alloc(name, local); |
399 | if (!ref) { | |
0fb9a9ec JP |
400 | wiphy_warn(local->hw.wiphy, |
401 | "Failed to select rate control algorithm\n"); | |
ff688089 JB |
402 | return -ENOENT; |
403 | } | |
404 | ||
889cbb91 | 405 | WARN_ON(local->rate_ctrl); |
ff688089 | 406 | local->rate_ctrl = ref; |
ff688089 | 407 | |
0fb9a9ec JP |
408 | wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", |
409 | ref->ops->name); | |
ff688089 | 410 | |
ff688089 JB |
411 | return 0; |
412 | } | |
413 | ||
414 | void rate_control_deinitialize(struct ieee80211_local *local) | |
415 | { | |
416 | struct rate_control_ref *ref; | |
417 | ||
418 | ref = local->rate_ctrl; | |
af65cd96 JB |
419 | |
420 | if (!ref) | |
421 | return; | |
422 | ||
ff688089 | 423 | local->rate_ctrl = NULL; |
889cbb91 | 424 | rate_control_free(ref); |
ff688089 | 425 | } |
c21b39ac | 426 |