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/module.h> 14 #include <linux/slab.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 const 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 void rate_control_rate_init(struct sta_info *sta) 33 { 34 struct ieee80211_local *local = sta->sdata->local; 35 struct rate_control_ref *ref = sta->rate_ctrl; 36 struct ieee80211_sta *ista = &sta->sta; 37 void *priv_sta = sta->rate_ctrl_priv; 38 struct ieee80211_supported_band *sband; 39 struct ieee80211_chanctx_conf *chanctx_conf; 40 41 ieee80211_sta_set_rx_nss(sta); 42 43 if (!ref) 44 return; 45 46 rcu_read_lock(); 47 48 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf); 49 if (WARN_ON(!chanctx_conf)) { 50 rcu_read_unlock(); 51 return; 52 } 53 54 sband = local->hw.wiphy->bands[chanctx_conf->def.chan->band]; 55 56 spin_lock_bh(&sta->rate_ctrl_lock); 57 ref->ops->rate_init(ref->priv, sband, &chanctx_conf->def, ista, 58 priv_sta); 59 spin_unlock_bh(&sta->rate_ctrl_lock); 60 rcu_read_unlock(); 61 set_sta_flag(sta, WLAN_STA_RATE_CONTROL); 62 } 63 64 void rate_control_rate_update(struct ieee80211_local *local, 65 struct ieee80211_supported_band *sband, 66 struct sta_info *sta, u32 changed) 67 { 68 struct rate_control_ref *ref = local->rate_ctrl; 69 struct ieee80211_sta *ista = &sta->sta; 70 void *priv_sta = sta->rate_ctrl_priv; 71 struct ieee80211_chanctx_conf *chanctx_conf; 72 73 if (ref && ref->ops->rate_update) { 74 rcu_read_lock(); 75 76 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf); 77 if (WARN_ON(!chanctx_conf)) { 78 rcu_read_unlock(); 79 return; 80 } 81 82 spin_lock_bh(&sta->rate_ctrl_lock); 83 ref->ops->rate_update(ref->priv, sband, &chanctx_conf->def, 84 ista, priv_sta, changed); 85 spin_unlock_bh(&sta->rate_ctrl_lock); 86 rcu_read_unlock(); 87 } 88 drv_sta_rc_update(local, sta->sdata, &sta->sta, changed); 89 } 90 91 int ieee80211_rate_control_register(const struct rate_control_ops *ops) 92 { 93 struct rate_control_alg *alg; 94 95 if (!ops->name) 96 return -EINVAL; 97 98 mutex_lock(&rate_ctrl_mutex); 99 list_for_each_entry(alg, &rate_ctrl_algs, list) { 100 if (!strcmp(alg->ops->name, ops->name)) { 101 /* don't register an algorithm twice */ 102 WARN_ON(1); 103 mutex_unlock(&rate_ctrl_mutex); 104 return -EALREADY; 105 } 106 } 107 108 alg = kzalloc(sizeof(*alg), GFP_KERNEL); 109 if (alg == NULL) { 110 mutex_unlock(&rate_ctrl_mutex); 111 return -ENOMEM; 112 } 113 alg->ops = ops; 114 115 list_add_tail(&alg->list, &rate_ctrl_algs); 116 mutex_unlock(&rate_ctrl_mutex); 117 118 return 0; 119 } 120 EXPORT_SYMBOL(ieee80211_rate_control_register); 121 122 void ieee80211_rate_control_unregister(const struct rate_control_ops *ops) 123 { 124 struct rate_control_alg *alg; 125 126 mutex_lock(&rate_ctrl_mutex); 127 list_for_each_entry(alg, &rate_ctrl_algs, list) { 128 if (alg->ops == ops) { 129 list_del(&alg->list); 130 kfree(alg); 131 break; 132 } 133 } 134 mutex_unlock(&rate_ctrl_mutex); 135 } 136 EXPORT_SYMBOL(ieee80211_rate_control_unregister); 137 138 static const struct rate_control_ops * 139 ieee80211_try_rate_control_ops_get(const char *name) 140 { 141 struct rate_control_alg *alg; 142 const struct rate_control_ops *ops = NULL; 143 144 if (!name) 145 return NULL; 146 147 mutex_lock(&rate_ctrl_mutex); 148 list_for_each_entry(alg, &rate_ctrl_algs, list) { 149 if (!strcmp(alg->ops->name, name)) { 150 ops = alg->ops; 151 break; 152 } 153 } 154 mutex_unlock(&rate_ctrl_mutex); 155 return ops; 156 } 157 158 /* Get the rate control algorithm. */ 159 static const struct rate_control_ops * 160 ieee80211_rate_control_ops_get(const char *name) 161 { 162 const struct rate_control_ops *ops; 163 const char *alg_name; 164 165 kernel_param_lock(THIS_MODULE); 166 if (!name) 167 alg_name = ieee80211_default_rc_algo; 168 else 169 alg_name = name; 170 171 ops = ieee80211_try_rate_control_ops_get(alg_name); 172 if (!ops && name) 173 /* try default if specific alg requested but not found */ 174 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo); 175 176 /* try built-in one if specific alg requested but not found */ 177 if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT)) 178 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT); 179 kernel_param_unlock(THIS_MODULE); 180 181 return ops; 182 } 183 184 #ifdef CONFIG_MAC80211_DEBUGFS 185 static ssize_t rcname_read(struct file *file, char __user *userbuf, 186 size_t count, loff_t *ppos) 187 { 188 struct rate_control_ref *ref = file->private_data; 189 int len = strlen(ref->ops->name); 190 191 return simple_read_from_buffer(userbuf, count, ppos, 192 ref->ops->name, len); 193 } 194 195 static const struct file_operations rcname_ops = { 196 .read = rcname_read, 197 .open = simple_open, 198 .llseek = default_llseek, 199 }; 200 #endif 201 202 static struct rate_control_ref *rate_control_alloc(const char *name, 203 struct ieee80211_local *local) 204 { 205 struct dentry *debugfsdir = NULL; 206 struct rate_control_ref *ref; 207 208 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL); 209 if (!ref) 210 return NULL; 211 ref->local = local; 212 ref->ops = ieee80211_rate_control_ops_get(name); 213 if (!ref->ops) 214 goto free; 215 216 #ifdef CONFIG_MAC80211_DEBUGFS 217 debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir); 218 local->debugfs.rcdir = debugfsdir; 219 debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops); 220 #endif 221 222 ref->priv = ref->ops->alloc(&local->hw, debugfsdir); 223 if (!ref->priv) 224 goto free; 225 return ref; 226 227 free: 228 kfree(ref); 229 return NULL; 230 } 231 232 static void rate_control_free(struct rate_control_ref *ctrl_ref) 233 { 234 ctrl_ref->ops->free(ctrl_ref->priv); 235 236 #ifdef CONFIG_MAC80211_DEBUGFS 237 debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir); 238 ctrl_ref->local->debugfs.rcdir = NULL; 239 #endif 240 241 kfree(ctrl_ref); 242 } 243 244 static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc) 245 { 246 struct sk_buff *skb = txrc->skb; 247 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 248 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 249 __le16 fc; 250 251 fc = hdr->frame_control; 252 253 return (info->flags & (IEEE80211_TX_CTL_NO_ACK | 254 IEEE80211_TX_CTL_USE_MINRATE)) || 255 !ieee80211_is_data(fc); 256 } 257 258 static void rc_send_low_basicrate(s8 *idx, u32 basic_rates, 259 struct ieee80211_supported_band *sband) 260 { 261 u8 i; 262 263 if (basic_rates == 0) 264 return; /* assume basic rates unknown and accept rate */ 265 if (*idx < 0) 266 return; 267 if (basic_rates & (1 << *idx)) 268 return; /* selected rate is a basic rate */ 269 270 for (i = *idx + 1; i <= sband->n_bitrates; i++) { 271 if (basic_rates & (1 << i)) { 272 *idx = i; 273 return; 274 } 275 } 276 277 /* could not find a basic rate; use original selection */ 278 } 279 280 static void __rate_control_send_low(struct ieee80211_hw *hw, 281 struct ieee80211_supported_band *sband, 282 struct ieee80211_sta *sta, 283 struct ieee80211_tx_info *info, 284 u32 rate_mask) 285 { 286 int i; 287 u32 rate_flags = 288 ieee80211_chandef_rate_flags(&hw->conf.chandef); 289 290 if ((sband->band == IEEE80211_BAND_2GHZ) && 291 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE)) 292 rate_flags |= IEEE80211_RATE_ERP_G; 293 294 info->control.rates[0].idx = 0; 295 for (i = 0; i < sband->n_bitrates; i++) { 296 if (!(rate_mask & BIT(i))) 297 continue; 298 299 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 300 continue; 301 302 if (!rate_supported(sta, sband->band, i)) 303 continue; 304 305 info->control.rates[0].idx = i; 306 break; 307 } 308 WARN_ONCE(i == sband->n_bitrates, 309 "no supported rates (0x%x) in rate_mask 0x%x with flags 0x%x\n", 310 sta ? sta->supp_rates[sband->band] : -1, 311 rate_mask, rate_flags); 312 313 info->control.rates[0].count = 314 (info->flags & IEEE80211_TX_CTL_NO_ACK) ? 315 1 : hw->max_rate_tries; 316 317 info->control.skip_table = 1; 318 } 319 320 321 bool rate_control_send_low(struct ieee80211_sta *pubsta, 322 void *priv_sta, 323 struct ieee80211_tx_rate_control *txrc) 324 { 325 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 326 struct ieee80211_supported_band *sband = txrc->sband; 327 struct sta_info *sta; 328 int mcast_rate; 329 bool use_basicrate = false; 330 331 if (!pubsta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) { 332 __rate_control_send_low(txrc->hw, sband, pubsta, info, 333 txrc->rate_idx_mask); 334 335 if (!pubsta && txrc->bss) { 336 mcast_rate = txrc->bss_conf->mcast_rate[sband->band]; 337 if (mcast_rate > 0) { 338 info->control.rates[0].idx = mcast_rate - 1; 339 return true; 340 } 341 use_basicrate = true; 342 } else if (pubsta) { 343 sta = container_of(pubsta, struct sta_info, sta); 344 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) 345 use_basicrate = true; 346 } 347 348 if (use_basicrate) 349 rc_send_low_basicrate(&info->control.rates[0].idx, 350 txrc->bss_conf->basic_rates, 351 sband); 352 353 return true; 354 } 355 return false; 356 } 357 EXPORT_SYMBOL(rate_control_send_low); 358 359 static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask) 360 { 361 int j; 362 363 /* See whether the selected rate or anything below it is allowed. */ 364 for (j = *rate_idx; j >= 0; j--) { 365 if (mask & (1 << j)) { 366 /* Okay, found a suitable rate. Use it. */ 367 *rate_idx = j; 368 return true; 369 } 370 } 371 372 /* Try to find a higher rate that would be allowed */ 373 for (j = *rate_idx + 1; j < n_bitrates; j++) { 374 if (mask & (1 << j)) { 375 /* Okay, found a suitable rate. Use it. */ 376 *rate_idx = j; 377 return true; 378 } 379 } 380 return false; 381 } 382 383 static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask) 384 { 385 int i, j; 386 int ridx, rbit; 387 388 ridx = *rate_idx / 8; 389 rbit = *rate_idx % 8; 390 391 /* sanity check */ 392 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN) 393 return false; 394 395 /* See whether the selected rate or anything below it is allowed. */ 396 for (i = ridx; i >= 0; i--) { 397 for (j = rbit; j >= 0; j--) 398 if (mcs_mask[i] & BIT(j)) { 399 *rate_idx = i * 8 + j; 400 return true; 401 } 402 rbit = 7; 403 } 404 405 /* Try to find a higher rate that would be allowed */ 406 ridx = (*rate_idx + 1) / 8; 407 rbit = (*rate_idx + 1) % 8; 408 409 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) { 410 for (j = rbit; j < 8; j++) 411 if (mcs_mask[i] & BIT(j)) { 412 *rate_idx = i * 8 + j; 413 return true; 414 } 415 rbit = 0; 416 } 417 return false; 418 } 419 420 static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask) 421 { 422 int i, j; 423 int ridx, rbit; 424 425 ridx = *rate_idx >> 4; 426 rbit = *rate_idx & 0xf; 427 428 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX) 429 return false; 430 431 /* See whether the selected rate or anything below it is allowed. */ 432 for (i = ridx; i >= 0; i--) { 433 for (j = rbit; j >= 0; j--) { 434 if (vht_mask[i] & BIT(j)) { 435 *rate_idx = (i << 4) | j; 436 return true; 437 } 438 } 439 rbit = 15; 440 } 441 442 /* Try to find a higher rate that would be allowed */ 443 ridx = (*rate_idx + 1) >> 4; 444 rbit = (*rate_idx + 1) & 0xf; 445 446 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) { 447 for (j = rbit; j < 16; j++) { 448 if (vht_mask[i] & BIT(j)) { 449 *rate_idx = (i << 4) | j; 450 return true; 451 } 452 } 453 rbit = 0; 454 } 455 return false; 456 } 457 458 static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags, 459 struct ieee80211_supported_band *sband, 460 enum nl80211_chan_width chan_width, 461 u32 mask, 462 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 463 u16 vht_mask[NL80211_VHT_NSS_MAX]) 464 { 465 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) { 466 /* handle VHT rates */ 467 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask)) 468 return; 469 470 *rate_idx = 0; 471 /* keep protection flags */ 472 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 473 IEEE80211_TX_RC_USE_CTS_PROTECT | 474 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 475 476 *rate_flags |= IEEE80211_TX_RC_MCS; 477 if (chan_width == NL80211_CHAN_WIDTH_40) 478 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 479 480 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 481 return; 482 483 /* also try the legacy rates. */ 484 *rate_flags &= ~(IEEE80211_TX_RC_MCS | 485 IEEE80211_TX_RC_40_MHZ_WIDTH); 486 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 487 mask)) 488 return; 489 } else if (*rate_flags & IEEE80211_TX_RC_MCS) { 490 /* handle HT rates */ 491 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 492 return; 493 494 /* also try the legacy rates. */ 495 *rate_idx = 0; 496 /* keep protection flags */ 497 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 498 IEEE80211_TX_RC_USE_CTS_PROTECT | 499 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 500 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 501 mask)) 502 return; 503 } else { 504 /* handle legacy rates */ 505 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 506 mask)) 507 return; 508 509 /* if HT BSS, and we handle a data frame, also try HT rates */ 510 switch (chan_width) { 511 case NL80211_CHAN_WIDTH_20_NOHT: 512 case NL80211_CHAN_WIDTH_5: 513 case NL80211_CHAN_WIDTH_10: 514 return; 515 default: 516 break; 517 } 518 519 *rate_idx = 0; 520 /* keep protection flags */ 521 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 522 IEEE80211_TX_RC_USE_CTS_PROTECT | 523 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 524 525 *rate_flags |= IEEE80211_TX_RC_MCS; 526 527 if (chan_width == NL80211_CHAN_WIDTH_40) 528 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 529 530 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 531 return; 532 } 533 534 /* 535 * Uh.. No suitable rate exists. This should not really happen with 536 * sane TX rate mask configurations. However, should someone manage to 537 * configure supported rates and TX rate mask in incompatible way, 538 * allow the frame to be transmitted with whatever the rate control 539 * selected. 540 */ 541 } 542 543 static void rate_fixup_ratelist(struct ieee80211_vif *vif, 544 struct ieee80211_supported_band *sband, 545 struct ieee80211_tx_info *info, 546 struct ieee80211_tx_rate *rates, 547 int max_rates) 548 { 549 struct ieee80211_rate *rate; 550 bool inval = false; 551 int i; 552 553 /* 554 * Set up the RTS/CTS rate as the fastest basic rate 555 * that is not faster than the data rate unless there 556 * is no basic rate slower than the data rate, in which 557 * case we pick the slowest basic rate 558 * 559 * XXX: Should this check all retry rates? 560 */ 561 if (!(rates[0].flags & 562 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) { 563 u32 basic_rates = vif->bss_conf.basic_rates; 564 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0; 565 566 rate = &sband->bitrates[rates[0].idx]; 567 568 for (i = 0; i < sband->n_bitrates; i++) { 569 /* must be a basic rate */ 570 if (!(basic_rates & BIT(i))) 571 continue; 572 /* must not be faster than the data rate */ 573 if (sband->bitrates[i].bitrate > rate->bitrate) 574 continue; 575 /* maximum */ 576 if (sband->bitrates[baserate].bitrate < 577 sband->bitrates[i].bitrate) 578 baserate = i; 579 } 580 581 info->control.rts_cts_rate_idx = baserate; 582 } 583 584 for (i = 0; i < max_rates; i++) { 585 /* 586 * make sure there's no valid rate following 587 * an invalid one, just in case drivers don't 588 * take the API seriously to stop at -1. 589 */ 590 if (inval) { 591 rates[i].idx = -1; 592 continue; 593 } 594 if (rates[i].idx < 0) { 595 inval = true; 596 continue; 597 } 598 599 /* 600 * For now assume MCS is already set up correctly, this 601 * needs to be fixed. 602 */ 603 if (rates[i].flags & IEEE80211_TX_RC_MCS) { 604 WARN_ON(rates[i].idx > 76); 605 606 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 607 info->control.use_cts_prot) 608 rates[i].flags |= 609 IEEE80211_TX_RC_USE_CTS_PROTECT; 610 continue; 611 } 612 613 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) { 614 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9); 615 continue; 616 } 617 618 /* set up RTS protection if desired */ 619 if (info->control.use_rts) { 620 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS; 621 info->control.use_cts_prot = false; 622 } 623 624 /* RC is busted */ 625 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) { 626 rates[i].idx = -1; 627 continue; 628 } 629 630 rate = &sband->bitrates[rates[i].idx]; 631 632 /* set up short preamble */ 633 if (info->control.short_preamble && 634 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 635 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 636 637 /* set up G protection */ 638 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 639 info->control.use_cts_prot && 640 rate->flags & IEEE80211_RATE_ERP_G) 641 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT; 642 } 643 } 644 645 646 static void rate_control_fill_sta_table(struct ieee80211_sta *sta, 647 struct ieee80211_tx_info *info, 648 struct ieee80211_tx_rate *rates, 649 int max_rates) 650 { 651 struct ieee80211_sta_rates *ratetbl = NULL; 652 int i; 653 654 if (sta && !info->control.skip_table) 655 ratetbl = rcu_dereference(sta->rates); 656 657 /* Fill remaining rate slots with data from the sta rate table. */ 658 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE); 659 for (i = 0; i < max_rates; i++) { 660 if (i < ARRAY_SIZE(info->control.rates) && 661 info->control.rates[i].idx >= 0 && 662 info->control.rates[i].count) { 663 if (rates != info->control.rates) 664 rates[i] = info->control.rates[i]; 665 } else if (ratetbl) { 666 rates[i].idx = ratetbl->rate[i].idx; 667 rates[i].flags = ratetbl->rate[i].flags; 668 if (info->control.use_rts) 669 rates[i].count = ratetbl->rate[i].count_rts; 670 else if (info->control.use_cts_prot) 671 rates[i].count = ratetbl->rate[i].count_cts; 672 else 673 rates[i].count = ratetbl->rate[i].count; 674 } else { 675 rates[i].idx = -1; 676 rates[i].count = 0; 677 } 678 679 if (rates[i].idx < 0 || !rates[i].count) 680 break; 681 } 682 } 683 684 static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata, 685 struct ieee80211_supported_band *sband, 686 struct ieee80211_sta *sta, u32 *mask, 687 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 688 u16 vht_mask[NL80211_VHT_NSS_MAX]) 689 { 690 u32 i, flags; 691 692 *mask = sdata->rc_rateidx_mask[sband->band]; 693 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef); 694 for (i = 0; i < sband->n_bitrates; i++) { 695 if ((flags & sband->bitrates[i].flags) != flags) 696 *mask &= ~BIT(i); 697 } 698 699 if (*mask == (1 << sband->n_bitrates) - 1 && 700 !sdata->rc_has_mcs_mask[sband->band] && 701 !sdata->rc_has_vht_mcs_mask[sband->band]) 702 return false; 703 704 if (sdata->rc_has_mcs_mask[sband->band]) 705 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band], 706 IEEE80211_HT_MCS_MASK_LEN); 707 else 708 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN); 709 710 if (sdata->rc_has_vht_mcs_mask[sband->band]) 711 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band], 712 sizeof(u16) * NL80211_VHT_NSS_MAX); 713 else 714 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX); 715 716 if (sta) { 717 __le16 sta_vht_cap; 718 u16 sta_vht_mask[NL80211_VHT_NSS_MAX]; 719 720 /* Filter out rates that the STA does not support */ 721 *mask &= sta->supp_rates[sband->band]; 722 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) 723 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i]; 724 725 sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map; 726 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask); 727 for (i = 0; i < NL80211_VHT_NSS_MAX; i++) 728 vht_mask[i] &= sta_vht_mask[i]; 729 } 730 731 return true; 732 } 733 734 static void 735 rate_control_apply_mask_ratetbl(struct sta_info *sta, 736 struct ieee80211_supported_band *sband, 737 struct ieee80211_sta_rates *rates) 738 { 739 int i; 740 u32 mask; 741 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 742 u16 vht_mask[NL80211_VHT_NSS_MAX]; 743 enum nl80211_chan_width chan_width; 744 745 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask, 746 mcs_mask, vht_mask)) 747 return; 748 749 chan_width = sta->sdata->vif.bss_conf.chandef.width; 750 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) { 751 if (rates->rate[i].idx < 0) 752 break; 753 754 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags, 755 sband, chan_width, mask, mcs_mask, 756 vht_mask); 757 } 758 } 759 760 static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata, 761 struct ieee80211_sta *sta, 762 struct ieee80211_supported_band *sband, 763 struct ieee80211_tx_rate *rates, 764 int max_rates) 765 { 766 enum nl80211_chan_width chan_width; 767 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 768 u32 mask; 769 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX]; 770 int i; 771 772 /* 773 * Try to enforce the rateidx mask the user wanted. skip this if the 774 * default mask (allow all rates) is used to save some processing for 775 * the common case. 776 */ 777 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask, 778 vht_mask)) 779 return; 780 781 /* 782 * Make sure the rate index selected for each TX rate is 783 * included in the configured mask and change the rate indexes 784 * if needed. 785 */ 786 chan_width = sdata->vif.bss_conf.chandef.width; 787 for (i = 0; i < max_rates; i++) { 788 /* Skip invalid rates */ 789 if (rates[i].idx < 0) 790 break; 791 792 rate_flags = rates[i].flags; 793 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband, 794 chan_width, mask, mcs_mask, vht_mask); 795 rates[i].flags = rate_flags; 796 } 797 } 798 799 void ieee80211_get_tx_rates(struct ieee80211_vif *vif, 800 struct ieee80211_sta *sta, 801 struct sk_buff *skb, 802 struct ieee80211_tx_rate *dest, 803 int max_rates) 804 { 805 struct ieee80211_sub_if_data *sdata; 806 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 807 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 808 struct ieee80211_supported_band *sband; 809 810 rate_control_fill_sta_table(sta, info, dest, max_rates); 811 812 if (!vif) 813 return; 814 815 sdata = vif_to_sdata(vif); 816 sband = sdata->local->hw.wiphy->bands[info->band]; 817 818 if (ieee80211_is_data(hdr->frame_control)) 819 rate_control_apply_mask(sdata, sta, sband, dest, max_rates); 820 821 if (dest[0].idx < 0) 822 __rate_control_send_low(&sdata->local->hw, sband, sta, info, 823 sdata->rc_rateidx_mask[info->band]); 824 825 if (sta) 826 rate_fixup_ratelist(vif, sband, info, dest, max_rates); 827 } 828 EXPORT_SYMBOL(ieee80211_get_tx_rates); 829 830 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, 831 struct sta_info *sta, 832 struct ieee80211_tx_rate_control *txrc) 833 { 834 struct rate_control_ref *ref = sdata->local->rate_ctrl; 835 void *priv_sta = NULL; 836 struct ieee80211_sta *ista = NULL; 837 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 838 int i; 839 840 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) { 841 ista = &sta->sta; 842 priv_sta = sta->rate_ctrl_priv; 843 } 844 845 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 846 info->control.rates[i].idx = -1; 847 info->control.rates[i].flags = 0; 848 info->control.rates[i].count = 0; 849 } 850 851 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL)) 852 return; 853 854 if (ista) { 855 spin_lock_bh(&sta->rate_ctrl_lock); 856 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); 857 spin_unlock_bh(&sta->rate_ctrl_lock); 858 } else { 859 ref->ops->get_rate(ref->priv, NULL, NULL, txrc); 860 } 861 862 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE)) 863 return; 864 865 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb, 866 info->control.rates, 867 ARRAY_SIZE(info->control.rates)); 868 } 869 870 int rate_control_set_rates(struct ieee80211_hw *hw, 871 struct ieee80211_sta *pubsta, 872 struct ieee80211_sta_rates *rates) 873 { 874 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 875 struct ieee80211_sta_rates *old; 876 struct ieee80211_supported_band *sband; 877 878 sband = hw->wiphy->bands[ieee80211_get_sdata_band(sta->sdata)]; 879 rate_control_apply_mask_ratetbl(sta, sband, rates); 880 /* 881 * mac80211 guarantees that this function will not be called 882 * concurrently, so the following RCU access is safe, even without 883 * extra locking. This can not be checked easily, so we just set 884 * the condition to true. 885 */ 886 old = rcu_dereference_protected(pubsta->rates, true); 887 rcu_assign_pointer(pubsta->rates, rates); 888 if (old) 889 kfree_rcu(old, rcu_head); 890 891 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta); 892 893 return 0; 894 } 895 EXPORT_SYMBOL(rate_control_set_rates); 896 897 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, 898 const char *name) 899 { 900 struct rate_control_ref *ref; 901 902 ASSERT_RTNL(); 903 904 if (local->open_count) 905 return -EBUSY; 906 907 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) { 908 if (WARN_ON(!local->ops->set_rts_threshold)) 909 return -EINVAL; 910 return 0; 911 } 912 913 ref = rate_control_alloc(name, local); 914 if (!ref) { 915 wiphy_warn(local->hw.wiphy, 916 "Failed to select rate control algorithm\n"); 917 return -ENOENT; 918 } 919 920 WARN_ON(local->rate_ctrl); 921 local->rate_ctrl = ref; 922 923 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", 924 ref->ops->name); 925 926 return 0; 927 } 928 929 void rate_control_deinitialize(struct ieee80211_local *local) 930 { 931 struct rate_control_ref *ref; 932 933 ref = local->rate_ctrl; 934 935 if (!ref) 936 return; 937 938 local->rate_ctrl = NULL; 939 rate_control_free(ref); 940 } 941 942