1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2002-2005, Instant802 Networks, Inc. 4 * Copyright 2005-2006, Devicescape Software, Inc. 5 * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz> 6 * Copyright 2017 Intel Deutschland GmbH 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/rtnetlink.h> 11 #include <linux/module.h> 12 #include <linux/slab.h> 13 #include "rate.h" 14 #include "ieee80211_i.h" 15 #include "debugfs.h" 16 17 struct rate_control_alg { 18 struct list_head list; 19 const struct rate_control_ops *ops; 20 }; 21 22 static LIST_HEAD(rate_ctrl_algs); 23 static DEFINE_MUTEX(rate_ctrl_mutex); 24 25 static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT; 26 module_param(ieee80211_default_rc_algo, charp, 0644); 27 MODULE_PARM_DESC(ieee80211_default_rc_algo, 28 "Default rate control algorithm for mac80211 to use"); 29 30 void rate_control_rate_init(struct sta_info *sta) 31 { 32 struct ieee80211_local *local = sta->sdata->local; 33 struct rate_control_ref *ref = sta->rate_ctrl; 34 struct ieee80211_sta *ista = &sta->sta; 35 void *priv_sta = sta->rate_ctrl_priv; 36 struct ieee80211_supported_band *sband; 37 struct ieee80211_chanctx_conf *chanctx_conf; 38 39 ieee80211_sta_set_rx_nss(sta); 40 41 if (!ref) 42 return; 43 44 rcu_read_lock(); 45 46 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf); 47 if (WARN_ON(!chanctx_conf)) { 48 rcu_read_unlock(); 49 return; 50 } 51 52 sband = local->hw.wiphy->bands[chanctx_conf->def.chan->band]; 53 54 spin_lock_bh(&sta->rate_ctrl_lock); 55 ref->ops->rate_init(ref->priv, sband, &chanctx_conf->def, ista, 56 priv_sta); 57 spin_unlock_bh(&sta->rate_ctrl_lock); 58 rcu_read_unlock(); 59 set_sta_flag(sta, WLAN_STA_RATE_CONTROL); 60 } 61 62 void rate_control_tx_status(struct ieee80211_local *local, 63 struct ieee80211_supported_band *sband, 64 struct ieee80211_tx_status *st) 65 { 66 struct rate_control_ref *ref = local->rate_ctrl; 67 struct sta_info *sta = container_of(st->sta, struct sta_info, sta); 68 void *priv_sta = sta->rate_ctrl_priv; 69 70 if (!ref || !test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) 71 return; 72 73 spin_lock_bh(&sta->rate_ctrl_lock); 74 if (ref->ops->tx_status_ext) 75 ref->ops->tx_status_ext(ref->priv, sband, priv_sta, st); 76 else if (st->skb) 77 ref->ops->tx_status(ref->priv, sband, st->sta, priv_sta, st->skb); 78 else 79 WARN_ON_ONCE(1); 80 81 spin_unlock_bh(&sta->rate_ctrl_lock); 82 } 83 84 void rate_control_rate_update(struct ieee80211_local *local, 85 struct ieee80211_supported_band *sband, 86 struct sta_info *sta, u32 changed) 87 { 88 struct rate_control_ref *ref = local->rate_ctrl; 89 struct ieee80211_sta *ista = &sta->sta; 90 void *priv_sta = sta->rate_ctrl_priv; 91 struct ieee80211_chanctx_conf *chanctx_conf; 92 93 if (ref && ref->ops->rate_update) { 94 rcu_read_lock(); 95 96 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf); 97 if (WARN_ON(!chanctx_conf)) { 98 rcu_read_unlock(); 99 return; 100 } 101 102 spin_lock_bh(&sta->rate_ctrl_lock); 103 ref->ops->rate_update(ref->priv, sband, &chanctx_conf->def, 104 ista, priv_sta, changed); 105 spin_unlock_bh(&sta->rate_ctrl_lock); 106 rcu_read_unlock(); 107 } 108 drv_sta_rc_update(local, sta->sdata, &sta->sta, changed); 109 } 110 111 int ieee80211_rate_control_register(const struct rate_control_ops *ops) 112 { 113 struct rate_control_alg *alg; 114 115 if (!ops->name) 116 return -EINVAL; 117 118 mutex_lock(&rate_ctrl_mutex); 119 list_for_each_entry(alg, &rate_ctrl_algs, list) { 120 if (!strcmp(alg->ops->name, ops->name)) { 121 /* don't register an algorithm twice */ 122 WARN_ON(1); 123 mutex_unlock(&rate_ctrl_mutex); 124 return -EALREADY; 125 } 126 } 127 128 alg = kzalloc(sizeof(*alg), GFP_KERNEL); 129 if (alg == NULL) { 130 mutex_unlock(&rate_ctrl_mutex); 131 return -ENOMEM; 132 } 133 alg->ops = ops; 134 135 list_add_tail(&alg->list, &rate_ctrl_algs); 136 mutex_unlock(&rate_ctrl_mutex); 137 138 return 0; 139 } 140 EXPORT_SYMBOL(ieee80211_rate_control_register); 141 142 void ieee80211_rate_control_unregister(const struct rate_control_ops *ops) 143 { 144 struct rate_control_alg *alg; 145 146 mutex_lock(&rate_ctrl_mutex); 147 list_for_each_entry(alg, &rate_ctrl_algs, list) { 148 if (alg->ops == ops) { 149 list_del(&alg->list); 150 kfree(alg); 151 break; 152 } 153 } 154 mutex_unlock(&rate_ctrl_mutex); 155 } 156 EXPORT_SYMBOL(ieee80211_rate_control_unregister); 157 158 static const struct rate_control_ops * 159 ieee80211_try_rate_control_ops_get(const char *name) 160 { 161 struct rate_control_alg *alg; 162 const struct rate_control_ops *ops = NULL; 163 164 if (!name) 165 return NULL; 166 167 mutex_lock(&rate_ctrl_mutex); 168 list_for_each_entry(alg, &rate_ctrl_algs, list) { 169 if (!strcmp(alg->ops->name, name)) { 170 ops = alg->ops; 171 break; 172 } 173 } 174 mutex_unlock(&rate_ctrl_mutex); 175 return ops; 176 } 177 178 /* Get the rate control algorithm. */ 179 static const struct rate_control_ops * 180 ieee80211_rate_control_ops_get(const char *name) 181 { 182 const struct rate_control_ops *ops; 183 const char *alg_name; 184 185 kernel_param_lock(THIS_MODULE); 186 if (!name) 187 alg_name = ieee80211_default_rc_algo; 188 else 189 alg_name = name; 190 191 ops = ieee80211_try_rate_control_ops_get(alg_name); 192 if (!ops && name) 193 /* try default if specific alg requested but not found */ 194 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo); 195 196 /* Note: check for > 0 is intentional to avoid clang warning */ 197 if (!ops && (strlen(CONFIG_MAC80211_RC_DEFAULT) > 0)) 198 /* try built-in one if specific alg requested but not found */ 199 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT); 200 201 kernel_param_unlock(THIS_MODULE); 202 203 return ops; 204 } 205 206 #ifdef CONFIG_MAC80211_DEBUGFS 207 static ssize_t rcname_read(struct file *file, char __user *userbuf, 208 size_t count, loff_t *ppos) 209 { 210 struct rate_control_ref *ref = file->private_data; 211 int len = strlen(ref->ops->name); 212 213 return simple_read_from_buffer(userbuf, count, ppos, 214 ref->ops->name, len); 215 } 216 217 const struct file_operations rcname_ops = { 218 .read = rcname_read, 219 .open = simple_open, 220 .llseek = default_llseek, 221 }; 222 #endif 223 224 static struct rate_control_ref * 225 rate_control_alloc(const char *name, struct ieee80211_local *local) 226 { 227 struct rate_control_ref *ref; 228 229 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL); 230 if (!ref) 231 return NULL; 232 ref->ops = ieee80211_rate_control_ops_get(name); 233 if (!ref->ops) 234 goto free; 235 236 ref->priv = ref->ops->alloc(&local->hw); 237 if (!ref->priv) 238 goto free; 239 return ref; 240 241 free: 242 kfree(ref); 243 return NULL; 244 } 245 246 static void rate_control_free(struct ieee80211_local *local, 247 struct rate_control_ref *ctrl_ref) 248 { 249 ctrl_ref->ops->free(ctrl_ref->priv); 250 251 #ifdef CONFIG_MAC80211_DEBUGFS 252 debugfs_remove_recursive(local->debugfs.rcdir); 253 local->debugfs.rcdir = NULL; 254 #endif 255 256 kfree(ctrl_ref); 257 } 258 259 void ieee80211_check_rate_mask(struct ieee80211_sub_if_data *sdata) 260 { 261 struct ieee80211_local *local = sdata->local; 262 struct ieee80211_supported_band *sband; 263 u32 user_mask, basic_rates = sdata->vif.bss_conf.basic_rates; 264 enum nl80211_band band; 265 266 if (WARN_ON(!sdata->vif.bss_conf.chandef.chan)) 267 return; 268 269 if (WARN_ON_ONCE(!basic_rates)) 270 return; 271 272 band = sdata->vif.bss_conf.chandef.chan->band; 273 user_mask = sdata->rc_rateidx_mask[band]; 274 sband = local->hw.wiphy->bands[band]; 275 276 if (user_mask & basic_rates) 277 return; 278 279 sdata_dbg(sdata, 280 "no overlap between basic rates (0x%x) and user mask (0x%x on band %d) - clearing the latter", 281 basic_rates, user_mask, band); 282 sdata->rc_rateidx_mask[band] = (1 << sband->n_bitrates) - 1; 283 } 284 285 static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc) 286 { 287 struct sk_buff *skb = txrc->skb; 288 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 289 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 290 __le16 fc; 291 292 fc = hdr->frame_control; 293 294 return (info->flags & (IEEE80211_TX_CTL_NO_ACK | 295 IEEE80211_TX_CTL_USE_MINRATE)) || 296 !ieee80211_is_data(fc); 297 } 298 299 static void rc_send_low_basicrate(s8 *idx, u32 basic_rates, 300 struct ieee80211_supported_band *sband) 301 { 302 u8 i; 303 304 if (basic_rates == 0) 305 return; /* assume basic rates unknown and accept rate */ 306 if (*idx < 0) 307 return; 308 if (basic_rates & (1 << *idx)) 309 return; /* selected rate is a basic rate */ 310 311 for (i = *idx + 1; i <= sband->n_bitrates; i++) { 312 if (basic_rates & (1 << i)) { 313 *idx = i; 314 return; 315 } 316 } 317 318 /* could not find a basic rate; use original selection */ 319 } 320 321 static void __rate_control_send_low(struct ieee80211_hw *hw, 322 struct ieee80211_supported_band *sband, 323 struct ieee80211_sta *sta, 324 struct ieee80211_tx_info *info, 325 u32 rate_mask) 326 { 327 int i; 328 u32 rate_flags = 329 ieee80211_chandef_rate_flags(&hw->conf.chandef); 330 331 if ((sband->band == NL80211_BAND_2GHZ) && 332 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE)) 333 rate_flags |= IEEE80211_RATE_ERP_G; 334 335 info->control.rates[0].idx = 0; 336 for (i = 0; i < sband->n_bitrates; i++) { 337 if (!(rate_mask & BIT(i))) 338 continue; 339 340 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 341 continue; 342 343 if (!rate_supported(sta, sband->band, i)) 344 continue; 345 346 info->control.rates[0].idx = i; 347 break; 348 } 349 WARN_ONCE(i == sband->n_bitrates, 350 "no supported rates for sta %pM (0x%x, band %d) in rate_mask 0x%x with flags 0x%x\n", 351 sta ? sta->addr : NULL, 352 sta ? sta->supp_rates[sband->band] : -1, 353 sband->band, 354 rate_mask, rate_flags); 355 356 info->control.rates[0].count = 357 (info->flags & IEEE80211_TX_CTL_NO_ACK) ? 358 1 : hw->max_rate_tries; 359 360 info->control.skip_table = 1; 361 } 362 363 364 static bool rate_control_send_low(struct ieee80211_sta *pubsta, 365 struct ieee80211_tx_rate_control *txrc) 366 { 367 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 368 struct ieee80211_supported_band *sband = txrc->sband; 369 struct sta_info *sta; 370 int mcast_rate; 371 bool use_basicrate = false; 372 373 if (!pubsta || rc_no_data_or_no_ack_use_min(txrc)) { 374 __rate_control_send_low(txrc->hw, sband, pubsta, info, 375 txrc->rate_idx_mask); 376 377 if (!pubsta && txrc->bss) { 378 mcast_rate = txrc->bss_conf->mcast_rate[sband->band]; 379 if (mcast_rate > 0) { 380 info->control.rates[0].idx = mcast_rate - 1; 381 return true; 382 } 383 use_basicrate = true; 384 } else if (pubsta) { 385 sta = container_of(pubsta, struct sta_info, sta); 386 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) 387 use_basicrate = true; 388 } 389 390 if (use_basicrate) 391 rc_send_low_basicrate(&info->control.rates[0].idx, 392 txrc->bss_conf->basic_rates, 393 sband); 394 395 return true; 396 } 397 return false; 398 } 399 400 static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask) 401 { 402 int j; 403 404 /* See whether the selected rate or anything below it is allowed. */ 405 for (j = *rate_idx; j >= 0; j--) { 406 if (mask & (1 << j)) { 407 /* Okay, found a suitable rate. Use it. */ 408 *rate_idx = j; 409 return true; 410 } 411 } 412 413 /* Try to find a higher rate that would be allowed */ 414 for (j = *rate_idx + 1; j < n_bitrates; j++) { 415 if (mask & (1 << j)) { 416 /* Okay, found a suitable rate. Use it. */ 417 *rate_idx = j; 418 return true; 419 } 420 } 421 return false; 422 } 423 424 static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask) 425 { 426 int i, j; 427 int ridx, rbit; 428 429 ridx = *rate_idx / 8; 430 rbit = *rate_idx % 8; 431 432 /* sanity check */ 433 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN) 434 return false; 435 436 /* See whether the selected rate or anything below it is allowed. */ 437 for (i = ridx; i >= 0; i--) { 438 for (j = rbit; j >= 0; j--) 439 if (mcs_mask[i] & BIT(j)) { 440 *rate_idx = i * 8 + j; 441 return true; 442 } 443 rbit = 7; 444 } 445 446 /* Try to find a higher rate that would be allowed */ 447 ridx = (*rate_idx + 1) / 8; 448 rbit = (*rate_idx + 1) % 8; 449 450 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) { 451 for (j = rbit; j < 8; j++) 452 if (mcs_mask[i] & BIT(j)) { 453 *rate_idx = i * 8 + j; 454 return true; 455 } 456 rbit = 0; 457 } 458 return false; 459 } 460 461 static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask) 462 { 463 int i, j; 464 int ridx, rbit; 465 466 ridx = *rate_idx >> 4; 467 rbit = *rate_idx & 0xf; 468 469 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX) 470 return false; 471 472 /* See whether the selected rate or anything below it is allowed. */ 473 for (i = ridx; i >= 0; i--) { 474 for (j = rbit; j >= 0; j--) { 475 if (vht_mask[i] & BIT(j)) { 476 *rate_idx = (i << 4) | j; 477 return true; 478 } 479 } 480 rbit = 15; 481 } 482 483 /* Try to find a higher rate that would be allowed */ 484 ridx = (*rate_idx + 1) >> 4; 485 rbit = (*rate_idx + 1) & 0xf; 486 487 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) { 488 for (j = rbit; j < 16; j++) { 489 if (vht_mask[i] & BIT(j)) { 490 *rate_idx = (i << 4) | j; 491 return true; 492 } 493 } 494 rbit = 0; 495 } 496 return false; 497 } 498 499 static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags, 500 struct ieee80211_supported_band *sband, 501 enum nl80211_chan_width chan_width, 502 u32 mask, 503 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 504 u16 vht_mask[NL80211_VHT_NSS_MAX]) 505 { 506 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) { 507 /* handle VHT rates */ 508 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask)) 509 return; 510 511 *rate_idx = 0; 512 /* keep protection flags */ 513 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 514 IEEE80211_TX_RC_USE_CTS_PROTECT | 515 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 516 517 *rate_flags |= IEEE80211_TX_RC_MCS; 518 if (chan_width == NL80211_CHAN_WIDTH_40) 519 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 520 521 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 522 return; 523 524 /* also try the legacy rates. */ 525 *rate_flags &= ~(IEEE80211_TX_RC_MCS | 526 IEEE80211_TX_RC_40_MHZ_WIDTH); 527 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 528 mask)) 529 return; 530 } else if (*rate_flags & IEEE80211_TX_RC_MCS) { 531 /* handle HT rates */ 532 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 533 return; 534 535 /* also try the legacy rates. */ 536 *rate_idx = 0; 537 /* keep protection flags */ 538 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 539 IEEE80211_TX_RC_USE_CTS_PROTECT | 540 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 541 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 542 mask)) 543 return; 544 } else { 545 /* handle legacy rates */ 546 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 547 mask)) 548 return; 549 550 /* if HT BSS, and we handle a data frame, also try HT rates */ 551 switch (chan_width) { 552 case NL80211_CHAN_WIDTH_20_NOHT: 553 case NL80211_CHAN_WIDTH_5: 554 case NL80211_CHAN_WIDTH_10: 555 return; 556 default: 557 break; 558 } 559 560 *rate_idx = 0; 561 /* keep protection flags */ 562 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 563 IEEE80211_TX_RC_USE_CTS_PROTECT | 564 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 565 566 *rate_flags |= IEEE80211_TX_RC_MCS; 567 568 if (chan_width == NL80211_CHAN_WIDTH_40) 569 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 570 571 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 572 return; 573 } 574 575 /* 576 * Uh.. No suitable rate exists. This should not really happen with 577 * sane TX rate mask configurations. However, should someone manage to 578 * configure supported rates and TX rate mask in incompatible way, 579 * allow the frame to be transmitted with whatever the rate control 580 * selected. 581 */ 582 } 583 584 static void rate_fixup_ratelist(struct ieee80211_vif *vif, 585 struct ieee80211_supported_band *sband, 586 struct ieee80211_tx_info *info, 587 struct ieee80211_tx_rate *rates, 588 int max_rates) 589 { 590 struct ieee80211_rate *rate; 591 bool inval = false; 592 int i; 593 594 /* 595 * Set up the RTS/CTS rate as the fastest basic rate 596 * that is not faster than the data rate unless there 597 * is no basic rate slower than the data rate, in which 598 * case we pick the slowest basic rate 599 * 600 * XXX: Should this check all retry rates? 601 */ 602 if (!(rates[0].flags & 603 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) { 604 u32 basic_rates = vif->bss_conf.basic_rates; 605 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0; 606 607 rate = &sband->bitrates[rates[0].idx]; 608 609 for (i = 0; i < sband->n_bitrates; i++) { 610 /* must be a basic rate */ 611 if (!(basic_rates & BIT(i))) 612 continue; 613 /* must not be faster than the data rate */ 614 if (sband->bitrates[i].bitrate > rate->bitrate) 615 continue; 616 /* maximum */ 617 if (sband->bitrates[baserate].bitrate < 618 sband->bitrates[i].bitrate) 619 baserate = i; 620 } 621 622 info->control.rts_cts_rate_idx = baserate; 623 } 624 625 for (i = 0; i < max_rates; i++) { 626 /* 627 * make sure there's no valid rate following 628 * an invalid one, just in case drivers don't 629 * take the API seriously to stop at -1. 630 */ 631 if (inval) { 632 rates[i].idx = -1; 633 continue; 634 } 635 if (rates[i].idx < 0) { 636 inval = true; 637 continue; 638 } 639 640 /* 641 * For now assume MCS is already set up correctly, this 642 * needs to be fixed. 643 */ 644 if (rates[i].flags & IEEE80211_TX_RC_MCS) { 645 WARN_ON(rates[i].idx > 76); 646 647 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 648 info->control.use_cts_prot) 649 rates[i].flags |= 650 IEEE80211_TX_RC_USE_CTS_PROTECT; 651 continue; 652 } 653 654 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) { 655 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9); 656 continue; 657 } 658 659 /* set up RTS protection if desired */ 660 if (info->control.use_rts) { 661 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS; 662 info->control.use_cts_prot = false; 663 } 664 665 /* RC is busted */ 666 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) { 667 rates[i].idx = -1; 668 continue; 669 } 670 671 rate = &sband->bitrates[rates[i].idx]; 672 673 /* set up short preamble */ 674 if (info->control.short_preamble && 675 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 676 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 677 678 /* set up G protection */ 679 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 680 info->control.use_cts_prot && 681 rate->flags & IEEE80211_RATE_ERP_G) 682 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT; 683 } 684 } 685 686 687 static void rate_control_fill_sta_table(struct ieee80211_sta *sta, 688 struct ieee80211_tx_info *info, 689 struct ieee80211_tx_rate *rates, 690 int max_rates) 691 { 692 struct ieee80211_sta_rates *ratetbl = NULL; 693 int i; 694 695 if (sta && !info->control.skip_table) 696 ratetbl = rcu_dereference(sta->rates); 697 698 /* Fill remaining rate slots with data from the sta rate table. */ 699 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE); 700 for (i = 0; i < max_rates; i++) { 701 if (i < ARRAY_SIZE(info->control.rates) && 702 info->control.rates[i].idx >= 0 && 703 info->control.rates[i].count) { 704 if (rates != info->control.rates) 705 rates[i] = info->control.rates[i]; 706 } else if (ratetbl) { 707 rates[i].idx = ratetbl->rate[i].idx; 708 rates[i].flags = ratetbl->rate[i].flags; 709 if (info->control.use_rts) 710 rates[i].count = ratetbl->rate[i].count_rts; 711 else if (info->control.use_cts_prot) 712 rates[i].count = ratetbl->rate[i].count_cts; 713 else 714 rates[i].count = ratetbl->rate[i].count; 715 } else { 716 rates[i].idx = -1; 717 rates[i].count = 0; 718 } 719 720 if (rates[i].idx < 0 || !rates[i].count) 721 break; 722 } 723 } 724 725 static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata, 726 struct ieee80211_supported_band *sband, 727 struct ieee80211_sta *sta, u32 *mask, 728 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 729 u16 vht_mask[NL80211_VHT_NSS_MAX]) 730 { 731 u32 i, flags; 732 733 *mask = sdata->rc_rateidx_mask[sband->band]; 734 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef); 735 for (i = 0; i < sband->n_bitrates; i++) { 736 if ((flags & sband->bitrates[i].flags) != flags) 737 *mask &= ~BIT(i); 738 } 739 740 if (*mask == (1 << sband->n_bitrates) - 1 && 741 !sdata->rc_has_mcs_mask[sband->band] && 742 !sdata->rc_has_vht_mcs_mask[sband->band]) 743 return false; 744 745 if (sdata->rc_has_mcs_mask[sband->band]) 746 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band], 747 IEEE80211_HT_MCS_MASK_LEN); 748 else 749 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN); 750 751 if (sdata->rc_has_vht_mcs_mask[sband->band]) 752 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band], 753 sizeof(u16) * NL80211_VHT_NSS_MAX); 754 else 755 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX); 756 757 if (sta) { 758 __le16 sta_vht_cap; 759 u16 sta_vht_mask[NL80211_VHT_NSS_MAX]; 760 761 /* Filter out rates that the STA does not support */ 762 *mask &= sta->supp_rates[sband->band]; 763 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) 764 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i]; 765 766 sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map; 767 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask); 768 for (i = 0; i < NL80211_VHT_NSS_MAX; i++) 769 vht_mask[i] &= sta_vht_mask[i]; 770 } 771 772 return true; 773 } 774 775 static void 776 rate_control_apply_mask_ratetbl(struct sta_info *sta, 777 struct ieee80211_supported_band *sband, 778 struct ieee80211_sta_rates *rates) 779 { 780 int i; 781 u32 mask; 782 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 783 u16 vht_mask[NL80211_VHT_NSS_MAX]; 784 enum nl80211_chan_width chan_width; 785 786 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask, 787 mcs_mask, vht_mask)) 788 return; 789 790 chan_width = sta->sdata->vif.bss_conf.chandef.width; 791 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) { 792 if (rates->rate[i].idx < 0) 793 break; 794 795 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags, 796 sband, chan_width, mask, mcs_mask, 797 vht_mask); 798 } 799 } 800 801 static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata, 802 struct ieee80211_sta *sta, 803 struct ieee80211_supported_band *sband, 804 struct ieee80211_tx_rate *rates, 805 int max_rates) 806 { 807 enum nl80211_chan_width chan_width; 808 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 809 u32 mask; 810 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX]; 811 int i; 812 813 /* 814 * Try to enforce the rateidx mask the user wanted. skip this if the 815 * default mask (allow all rates) is used to save some processing for 816 * the common case. 817 */ 818 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask, 819 vht_mask)) 820 return; 821 822 /* 823 * Make sure the rate index selected for each TX rate is 824 * included in the configured mask and change the rate indexes 825 * if needed. 826 */ 827 chan_width = sdata->vif.bss_conf.chandef.width; 828 for (i = 0; i < max_rates; i++) { 829 /* Skip invalid rates */ 830 if (rates[i].idx < 0) 831 break; 832 833 rate_flags = rates[i].flags; 834 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband, 835 chan_width, mask, mcs_mask, vht_mask); 836 rates[i].flags = rate_flags; 837 } 838 } 839 840 void ieee80211_get_tx_rates(struct ieee80211_vif *vif, 841 struct ieee80211_sta *sta, 842 struct sk_buff *skb, 843 struct ieee80211_tx_rate *dest, 844 int max_rates) 845 { 846 struct ieee80211_sub_if_data *sdata; 847 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 848 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 849 struct ieee80211_supported_band *sband; 850 851 rate_control_fill_sta_table(sta, info, dest, max_rates); 852 853 if (!vif) 854 return; 855 856 sdata = vif_to_sdata(vif); 857 sband = sdata->local->hw.wiphy->bands[info->band]; 858 859 if (ieee80211_is_data(hdr->frame_control)) 860 rate_control_apply_mask(sdata, sta, sband, dest, max_rates); 861 862 if (dest[0].idx < 0) 863 __rate_control_send_low(&sdata->local->hw, sband, sta, info, 864 sdata->rc_rateidx_mask[info->band]); 865 866 if (sta) 867 rate_fixup_ratelist(vif, sband, info, dest, max_rates); 868 } 869 EXPORT_SYMBOL(ieee80211_get_tx_rates); 870 871 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, 872 struct sta_info *sta, 873 struct ieee80211_tx_rate_control *txrc) 874 { 875 struct rate_control_ref *ref = sdata->local->rate_ctrl; 876 void *priv_sta = NULL; 877 struct ieee80211_sta *ista = NULL; 878 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 879 int i; 880 881 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 882 info->control.rates[i].idx = -1; 883 info->control.rates[i].flags = 0; 884 info->control.rates[i].count = 0; 885 } 886 887 if (rate_control_send_low(sta ? &sta->sta : NULL, txrc)) 888 return; 889 890 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL)) 891 return; 892 893 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) { 894 ista = &sta->sta; 895 priv_sta = sta->rate_ctrl_priv; 896 } 897 898 if (ista) { 899 spin_lock_bh(&sta->rate_ctrl_lock); 900 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); 901 spin_unlock_bh(&sta->rate_ctrl_lock); 902 } else { 903 rate_control_send_low(NULL, txrc); 904 } 905 906 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE)) 907 return; 908 909 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb, 910 info->control.rates, 911 ARRAY_SIZE(info->control.rates)); 912 } 913 914 int rate_control_set_rates(struct ieee80211_hw *hw, 915 struct ieee80211_sta *pubsta, 916 struct ieee80211_sta_rates *rates) 917 { 918 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 919 struct ieee80211_sta_rates *old; 920 struct ieee80211_supported_band *sband; 921 922 sband = ieee80211_get_sband(sta->sdata); 923 if (!sband) 924 return -EINVAL; 925 rate_control_apply_mask_ratetbl(sta, sband, rates); 926 /* 927 * mac80211 guarantees that this function will not be called 928 * concurrently, so the following RCU access is safe, even without 929 * extra locking. This can not be checked easily, so we just set 930 * the condition to true. 931 */ 932 old = rcu_dereference_protected(pubsta->rates, true); 933 rcu_assign_pointer(pubsta->rates, rates); 934 if (old) 935 kfree_rcu(old, rcu_head); 936 937 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta); 938 939 ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta)); 940 941 return 0; 942 } 943 EXPORT_SYMBOL(rate_control_set_rates); 944 945 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, 946 const char *name) 947 { 948 struct rate_control_ref *ref; 949 950 ASSERT_RTNL(); 951 952 if (local->open_count) 953 return -EBUSY; 954 955 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) { 956 if (WARN_ON(!local->ops->set_rts_threshold)) 957 return -EINVAL; 958 return 0; 959 } 960 961 ref = rate_control_alloc(name, local); 962 if (!ref) { 963 wiphy_warn(local->hw.wiphy, 964 "Failed to select rate control algorithm\n"); 965 return -ENOENT; 966 } 967 968 WARN_ON(local->rate_ctrl); 969 local->rate_ctrl = ref; 970 971 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", 972 ref->ops->name); 973 974 return 0; 975 } 976 977 void rate_control_deinitialize(struct ieee80211_local *local) 978 { 979 struct rate_control_ref *ref; 980 981 ref = local->rate_ctrl; 982 983 if (!ref) 984 return; 985 986 local->rate_ctrl = NULL; 987 rate_control_free(local, ref); 988 } 989