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; | |
162 | kref_init(&ref->kref); | |
4b7679a5 | 163 | ref->local = local; |
f0706e82 JB |
164 | ref->ops = ieee80211_rate_control_ops_get(name); |
165 | if (!ref->ops) | |
166 | goto fail_ops; | |
4b7679a5 JB |
167 | |
168 | #ifdef CONFIG_MAC80211_DEBUGFS | |
169 | debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir); | |
170 | local->debugfs.rcdir = debugfsdir; | |
7bcfaf2f | 171 | debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops); |
4b7679a5 JB |
172 | #endif |
173 | ||
174 | ref->priv = ref->ops->alloc(&local->hw, debugfsdir); | |
f0706e82 JB |
175 | if (!ref->priv) |
176 | goto fail_priv; | |
177 | return ref; | |
178 | ||
179 | fail_priv: | |
180 | ieee80211_rate_control_ops_put(ref->ops); | |
181 | fail_ops: | |
182 | kfree(ref); | |
183 | fail_ref: | |
184 | return NULL; | |
185 | } | |
186 | ||
187 | static void rate_control_release(struct kref *kref) | |
188 | { | |
189 | struct rate_control_ref *ctrl_ref; | |
190 | ||
191 | ctrl_ref = container_of(kref, struct rate_control_ref, kref); | |
192 | ctrl_ref->ops->free(ctrl_ref->priv); | |
4b7679a5 JB |
193 | |
194 | #ifdef CONFIG_MAC80211_DEBUGFS | |
7bcfaf2f | 195 | debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir); |
4b7679a5 JB |
196 | ctrl_ref->local->debugfs.rcdir = NULL; |
197 | #endif | |
198 | ||
f0706e82 JB |
199 | ieee80211_rate_control_ops_put(ctrl_ref->ops); |
200 | kfree(ctrl_ref); | |
201 | } | |
202 | ||
b6f35301 | 203 | static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc) |
4c6d4f5c LR |
204 | { |
205 | struct sk_buff *skb = txrc->skb; | |
206 | struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; | |
207 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); | |
208 | __le16 fc; | |
209 | ||
210 | fc = hdr->frame_control; | |
211 | ||
b6f35301 RM |
212 | return (info->flags & (IEEE80211_TX_CTL_NO_ACK | |
213 | IEEE80211_TX_CTL_USE_MINRATE)) || | |
214 | !ieee80211_is_data(fc); | |
4c6d4f5c LR |
215 | } |
216 | ||
dd5b4cc7 | 217 | static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, |
8f0729b1 | 218 | struct ieee80211_supported_band *sband) |
e00cfce0 JM |
219 | { |
220 | u8 i; | |
221 | ||
222 | if (basic_rates == 0) | |
223 | return; /* assume basic rates unknown and accept rate */ | |
224 | if (*idx < 0) | |
225 | return; | |
226 | if (basic_rates & (1 << *idx)) | |
227 | return; /* selected rate is a basic rate */ | |
228 | ||
8f0729b1 | 229 | for (i = *idx + 1; i <= sband->n_bitrates; i++) { |
e00cfce0 JM |
230 | if (basic_rates & (1 << i)) { |
231 | *idx = i; | |
232 | return; | |
233 | } | |
234 | } | |
235 | ||
236 | /* could not find a basic rate; use original selection */ | |
237 | } | |
238 | ||
aad14ceb RM |
239 | static inline s8 |
240 | rate_lowest_non_cck_index(struct ieee80211_supported_band *sband, | |
241 | struct ieee80211_sta *sta) | |
242 | { | |
243 | int i; | |
244 | ||
245 | for (i = 0; i < sband->n_bitrates; i++) { | |
246 | struct ieee80211_rate *srate = &sband->bitrates[i]; | |
247 | if ((srate->bitrate == 10) || (srate->bitrate == 20) || | |
248 | (srate->bitrate == 55) || (srate->bitrate == 110)) | |
249 | continue; | |
250 | ||
251 | if (rate_supported(sta, sband->band, i)) | |
252 | return i; | |
253 | } | |
254 | ||
255 | /* No matching rate found */ | |
256 | return 0; | |
257 | } | |
258 | ||
259 | ||
4c6d4f5c LR |
260 | bool rate_control_send_low(struct ieee80211_sta *sta, |
261 | void *priv_sta, | |
262 | struct ieee80211_tx_rate_control *txrc) | |
263 | { | |
264 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); | |
dd5b4cc7 FF |
265 | struct ieee80211_supported_band *sband = txrc->sband; |
266 | int mcast_rate; | |
4c6d4f5c | 267 | |
b6f35301 | 268 | if (!sta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) { |
aad14ceb RM |
269 | if ((sband->band != IEEE80211_BAND_2GHZ) || |
270 | !(info->flags & IEEE80211_TX_CTL_NO_CCK_RATE)) | |
271 | info->control.rates[0].idx = | |
272 | rate_lowest_index(txrc->sband, sta); | |
273 | else | |
274 | info->control.rates[0].idx = | |
275 | rate_lowest_non_cck_index(txrc->sband, sta); | |
4c6d4f5c LR |
276 | info->control.rates[0].count = |
277 | (info->flags & IEEE80211_TX_CTL_NO_ACK) ? | |
278 | 1 : txrc->hw->max_rate_tries; | |
dd5b4cc7 FF |
279 | if (!sta && txrc->bss) { |
280 | mcast_rate = txrc->bss_conf->mcast_rate[sband->band]; | |
281 | if (mcast_rate > 0) { | |
282 | info->control.rates[0].idx = mcast_rate - 1; | |
283 | return true; | |
284 | } | |
285 | ||
e00cfce0 JM |
286 | rc_send_low_broadcast(&info->control.rates[0].idx, |
287 | txrc->bss_conf->basic_rates, | |
dd5b4cc7 FF |
288 | sband); |
289 | } | |
4c6d4f5c LR |
290 | return true; |
291 | } | |
292 | return false; | |
293 | } | |
294 | EXPORT_SYMBOL(rate_control_send_low); | |
295 | ||
37eb0b16 JM |
296 | static void rate_idx_match_mask(struct ieee80211_tx_rate *rate, |
297 | int n_bitrates, u32 mask) | |
298 | { | |
299 | int j; | |
300 | ||
301 | /* See whether the selected rate or anything below it is allowed. */ | |
302 | for (j = rate->idx; j >= 0; j--) { | |
303 | if (mask & (1 << j)) { | |
304 | /* Okay, found a suitable rate. Use it. */ | |
305 | rate->idx = j; | |
306 | return; | |
307 | } | |
308 | } | |
309 | ||
310 | /* Try to find a higher rate that would be allowed */ | |
311 | for (j = rate->idx + 1; j < n_bitrates; j++) { | |
312 | if (mask & (1 << j)) { | |
313 | /* Okay, found a suitable rate. Use it. */ | |
314 | rate->idx = j; | |
315 | return; | |
316 | } | |
317 | } | |
318 | ||
319 | /* | |
320 | * Uh.. No suitable rate exists. This should not really happen with | |
321 | * sane TX rate mask configurations. However, should someone manage to | |
322 | * configure supported rates and TX rate mask in incompatible way, | |
323 | * allow the frame to be transmitted with whatever the rate control | |
324 | * selected. | |
325 | */ | |
326 | } | |
327 | ||
4b7679a5 | 328 | void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, |
e6a9854b JB |
329 | struct sta_info *sta, |
330 | struct ieee80211_tx_rate_control *txrc) | |
1abbe498 | 331 | { |
4b7679a5 JB |
332 | struct rate_control_ref *ref = sdata->local->rate_ctrl; |
333 | void *priv_sta = NULL; | |
334 | struct ieee80211_sta *ista = NULL; | |
e6a9854b | 335 | struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); |
1abbe498 | 336 | int i; |
37eb0b16 | 337 | u32 mask; |
1abbe498 | 338 | |
4b7679a5 JB |
339 | if (sta) { |
340 | ista = &sta->sta; | |
341 | priv_sta = sta->rate_ctrl_priv; | |
342 | } | |
343 | ||
e6a9854b JB |
344 | for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { |
345 | info->control.rates[i].idx = -1; | |
346 | info->control.rates[i].flags = 0; | |
347 | info->control.rates[i].count = 1; | |
348 | } | |
349 | ||
5affcd6b JO |
350 | if (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) |
351 | return; | |
352 | ||
37eb0b16 | 353 | ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); |
e6a9854b JB |
354 | |
355 | /* | |
37eb0b16 JM |
356 | * Try to enforce the rateidx mask the user wanted. skip this if the |
357 | * default mask (allow all rates) is used to save some processing for | |
358 | * the common case. | |
e6a9854b | 359 | */ |
37eb0b16 JM |
360 | mask = sdata->rc_rateidx_mask[info->band]; |
361 | if (mask != (1 << txrc->sband->n_bitrates) - 1) { | |
362 | if (sta) { | |
363 | /* Filter out rates that the STA does not support */ | |
364 | mask &= sta->sta.supp_rates[info->band]; | |
365 | } | |
366 | /* | |
367 | * Make sure the rate index selected for each TX rate is | |
368 | * included in the configured mask and change the rate indexes | |
369 | * if needed. | |
370 | */ | |
e6a9854b | 371 | for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { |
5f4e6b2d CL |
372 | /* Skip invalid rates */ |
373 | if (info->control.rates[i].idx < 0) | |
374 | break; | |
37eb0b16 | 375 | /* Rate masking supports only legacy rates for now */ |
e6a9854b JB |
376 | if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) |
377 | continue; | |
37eb0b16 JM |
378 | rate_idx_match_mask(&info->control.rates[i], |
379 | txrc->sband->n_bitrates, mask); | |
380 | } | |
1abbe498 | 381 | } |
e6a9854b JB |
382 | |
383 | BUG_ON(info->control.rates[0].idx < 0); | |
1abbe498 MN |
384 | } |
385 | ||
f0706e82 JB |
386 | struct rate_control_ref *rate_control_get(struct rate_control_ref *ref) |
387 | { | |
388 | kref_get(&ref->kref); | |
389 | return ref; | |
390 | } | |
391 | ||
392 | void rate_control_put(struct rate_control_ref *ref) | |
393 | { | |
394 | kref_put(&ref->kref, rate_control_release); | |
395 | } | |
ff688089 JB |
396 | |
397 | int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, | |
398 | const char *name) | |
399 | { | |
400 | struct rate_control_ref *ref, *old; | |
401 | ||
402 | ASSERT_RTNL(); | |
af65cd96 | 403 | |
3b8d81e0 | 404 | if (local->open_count) |
ff688089 JB |
405 | return -EBUSY; |
406 | ||
af65cd96 JB |
407 | if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) { |
408 | if (WARN_ON(!local->ops->set_rts_threshold)) | |
409 | return -EINVAL; | |
410 | return 0; | |
411 | } | |
412 | ||
ff688089 JB |
413 | ref = rate_control_alloc(name, local); |
414 | if (!ref) { | |
0fb9a9ec JP |
415 | wiphy_warn(local->hw.wiphy, |
416 | "Failed to select rate control algorithm\n"); | |
ff688089 JB |
417 | return -ENOENT; |
418 | } | |
419 | ||
420 | old = local->rate_ctrl; | |
421 | local->rate_ctrl = ref; | |
422 | if (old) { | |
423 | rate_control_put(old); | |
424 | sta_info_flush(local, NULL); | |
425 | } | |
426 | ||
0fb9a9ec JP |
427 | wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", |
428 | ref->ops->name); | |
ff688089 | 429 | |
ff688089 JB |
430 | return 0; |
431 | } | |
432 | ||
433 | void rate_control_deinitialize(struct ieee80211_local *local) | |
434 | { | |
435 | struct rate_control_ref *ref; | |
436 | ||
437 | ref = local->rate_ctrl; | |
af65cd96 JB |
438 | |
439 | if (!ref) | |
440 | return; | |
441 | ||
ff688089 JB |
442 | local->rate_ctrl = NULL; |
443 | rate_control_put(ref); | |
444 | } | |
c21b39ac | 445 |