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> 12 #include <linux/rtnetlink.h> 13 #include <linux/slab.h> 14 #include <linux/module.h> 15 #include "rate.h" 16 #include "ieee80211_i.h" 17 #include "debugfs.h" 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 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 32 int ieee80211_rate_control_register(struct rate_control_ops *ops) 33 { 34 struct rate_control_alg *alg; 35 36 if (!ops->name) 37 return -EINVAL; 38 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); 44 mutex_unlock(&rate_ctrl_mutex); 45 return -EALREADY; 46 } 47 } 48 49 alg = kzalloc(sizeof(*alg), GFP_KERNEL); 50 if (alg == NULL) { 51 mutex_unlock(&rate_ctrl_mutex); 52 return -ENOMEM; 53 } 54 alg->ops = ops; 55 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); 71 kfree(alg); 72 break; 73 } 74 } 75 mutex_unlock(&rate_ctrl_mutex); 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 85 if (!name) 86 return NULL; 87 88 mutex_lock(&rate_ctrl_mutex); 89 list_for_each_entry(alg, &rate_ctrl_algs, list) { 90 if (!strcmp(alg->ops->name, name)) 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 } 99 100 /* Get the rate control algorithm. */ 101 static struct rate_control_ops * 102 ieee80211_rate_control_ops_get(const char *name) 103 { 104 struct rate_control_ops *ops; 105 const char *alg_name; 106 107 kparam_block_sysfs_write(ieee80211_default_rc_algo); 108 if (!name) 109 alg_name = ieee80211_default_rc_algo; 110 else 111 alg_name = name; 112 113 ops = ieee80211_try_rate_control_ops_get(alg_name); 114 if (!ops) { 115 request_module("rc80211_%s", alg_name); 116 ops = ieee80211_try_rate_control_ops_get(alg_name); 117 } 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); 121 122 /* 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); 125 kparam_unblock_sysfs_write(ieee80211_default_rc_algo); 126 127 return ops; 128 } 129 130 static void ieee80211_rate_control_ops_put(struct rate_control_ops *ops) 131 { 132 module_put(ops->module); 133 } 134 135 #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 = simple_open, 149 .llseek = default_llseek, 150 }; 151 #endif 152 153 static struct rate_control_ref *rate_control_alloc(const char *name, 154 struct ieee80211_local *local) 155 { 156 struct dentry *debugfsdir = NULL; 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 ref->local = local; 163 ref->ops = ieee80211_rate_control_ops_get(name); 164 if (!ref->ops) 165 goto fail_ops; 166 167 #ifdef CONFIG_MAC80211_DEBUGFS 168 debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir); 169 local->debugfs.rcdir = debugfsdir; 170 debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops); 171 #endif 172 173 ref->priv = ref->ops->alloc(&local->hw, debugfsdir); 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 } 185 186 static void rate_control_free(struct rate_control_ref *ctrl_ref) 187 { 188 ctrl_ref->ops->free(ctrl_ref->priv); 189 190 #ifdef CONFIG_MAC80211_DEBUGFS 191 debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir); 192 ctrl_ref->local->debugfs.rcdir = NULL; 193 #endif 194 195 ieee80211_rate_control_ops_put(ctrl_ref->ops); 196 kfree(ctrl_ref); 197 } 198 199 static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc) 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; 207 208 return (info->flags & (IEEE80211_TX_CTL_NO_ACK | 209 IEEE80211_TX_CTL_USE_MINRATE)) || 210 !ieee80211_is_data(fc); 211 } 212 213 static void rc_send_low_basicrate(s8 *idx, u32 basic_rates, 214 struct ieee80211_supported_band *sband) 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 */ 224 225 for (i = *idx + 1; i <= sband->n_bitrates; i++) { 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 } 234 235 static void __rate_control_send_low(struct ieee80211_hw *hw, 236 struct ieee80211_supported_band *sband, 237 struct ieee80211_sta *sta, 238 struct ieee80211_tx_info *info, 239 u32 rate_mask) 240 { 241 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++) { 251 if (!(rate_mask & BIT(i))) 252 continue; 253 254 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 255 continue; 256 257 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); 264 265 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 } 271 272 273 bool rate_control_send_low(struct ieee80211_sta *pubsta, 274 void *priv_sta, 275 struct ieee80211_tx_rate_control *txrc) 276 { 277 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 278 struct ieee80211_supported_band *sband = txrc->sband; 279 struct sta_info *sta; 280 int mcast_rate; 281 bool use_basicrate = false; 282 283 if (!pubsta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) { 284 __rate_control_send_low(txrc->hw, sband, pubsta, info, 285 txrc->rate_idx_mask); 286 287 if (!pubsta && txrc->bss) { 288 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 } 293 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 } 299 300 if (use_basicrate) 301 rc_send_low_basicrate(&info->control.rates[0].idx, 302 txrc->bss_conf->basic_rates, 303 sband); 304 305 return true; 306 } 307 return false; 308 } 309 EXPORT_SYMBOL(rate_control_send_low); 310 311 static bool rate_idx_match_legacy_mask(struct ieee80211_tx_rate *rate, 312 int n_bitrates, u32 mask) 313 { 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; 321 return true; 322 } 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; 330 return true; 331 } 332 } 333 return false; 334 } 335 336 static 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 */ 346 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN) 347 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 } 373 374 375 376 static void rate_idx_match_mask(struct ieee80211_tx_rate *rate, 377 struct ieee80211_supported_band *sband, 378 enum nl80211_chan_width chan_width, 379 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, 398 sband->n_bitrates, mask)) { 399 *rate = alt_rate; 400 return; 401 } 402 } else { 403 /* handle legacy rates */ 404 if (rate_idx_match_legacy_mask(rate, sband->n_bitrates, mask)) 405 return; 406 407 /* if HT BSS, and we handle a data frame, also try HT rates */ 408 switch (chan_width) { 409 case NL80211_CHAN_WIDTH_20_NOHT: 410 case NL80211_CHAN_WIDTH_5: 411 case NL80211_CHAN_WIDTH_10: 412 return; 413 default: 414 break; 415 } 416 417 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; 426 427 if (chan_width == NL80211_CHAN_WIDTH_40) 428 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; 432 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 } 444 445 static 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 } 545 546 547 static 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 } 584 585 static 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; 596 u32 rate_flags; 597 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]; 606 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); 611 612 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; 638 639 rate_idx_match_mask(&rates[i], sband, chan_width, mask, 640 mcs_mask); 641 } 642 } 643 644 void 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) 667 __rate_control_send_low(&sdata->local->hw, sband, sta, info, 668 sdata->rc_rateidx_mask[info->band]); 669 670 if (sta) 671 rate_fixup_ratelist(vif, sband, info, dest, max_rates); 672 } 673 EXPORT_SYMBOL(ieee80211_get_tx_rates); 674 675 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, 676 struct sta_info *sta, 677 struct ieee80211_tx_rate_control *txrc) 678 { 679 struct rate_control_ref *ref = sdata->local->rate_ctrl; 680 void *priv_sta = NULL; 681 struct ieee80211_sta *ista = NULL; 682 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 683 int i; 684 685 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) { 686 ista = &sta->sta; 687 priv_sta = sta->rate_ctrl_priv; 688 } 689 690 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 691 info->control.rates[i].idx = -1; 692 info->control.rates[i].flags = 0; 693 info->control.rates[i].count = 0; 694 } 695 696 if (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) 697 return; 698 699 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); 700 701 if (sdata->local->hw.flags & IEEE80211_HW_SUPPORTS_RC_TABLE) 702 return; 703 704 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb, 705 info->control.rates, 706 ARRAY_SIZE(info->control.rates)); 707 } 708 709 int rate_control_set_rates(struct ieee80211_hw *hw, 710 struct ieee80211_sta *pubsta, 711 struct ieee80211_sta_rates *rates) 712 { 713 struct ieee80211_sta_rates *old; 714 715 /* 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); 722 rcu_assign_pointer(pubsta->rates, rates); 723 if (old) 724 kfree_rcu(old, rcu_head); 725 726 return 0; 727 } 728 EXPORT_SYMBOL(rate_control_set_rates); 729 730 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, 731 const char *name) 732 { 733 struct rate_control_ref *ref; 734 735 ASSERT_RTNL(); 736 737 if (local->open_count) 738 return -EBUSY; 739 740 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 } 745 746 ref = rate_control_alloc(name, local); 747 if (!ref) { 748 wiphy_warn(local->hw.wiphy, 749 "Failed to select rate control algorithm\n"); 750 return -ENOENT; 751 } 752 753 WARN_ON(local->rate_ctrl); 754 local->rate_ctrl = ref; 755 756 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", 757 ref->ops->name); 758 759 return 0; 760 } 761 762 void rate_control_deinitialize(struct ieee80211_local *local) 763 { 764 struct rate_control_ref *ref; 765 766 ref = local->rate_ctrl; 767 768 if (!ref) 769 return; 770 771 local->rate_ctrl = NULL; 772 rate_control_free(ref); 773 } 774 775