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 static 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 *rate_control_alloc(const char *name, 225 struct ieee80211_local *local) 226 { 227 struct dentry *debugfsdir = NULL; 228 struct rate_control_ref *ref; 229 230 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL); 231 if (!ref) 232 return NULL; 233 ref->ops = ieee80211_rate_control_ops_get(name); 234 if (!ref->ops) 235 goto free; 236 237 #ifdef CONFIG_MAC80211_DEBUGFS 238 debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir); 239 local->debugfs.rcdir = debugfsdir; 240 debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops); 241 #endif 242 243 ref->priv = ref->ops->alloc(&local->hw, debugfsdir); 244 if (!ref->priv) 245 goto free; 246 return ref; 247 248 free: 249 kfree(ref); 250 return NULL; 251 } 252 253 static void rate_control_free(struct ieee80211_local *local, 254 struct rate_control_ref *ctrl_ref) 255 { 256 ctrl_ref->ops->free(ctrl_ref->priv); 257 258 #ifdef CONFIG_MAC80211_DEBUGFS 259 debugfs_remove_recursive(local->debugfs.rcdir); 260 local->debugfs.rcdir = NULL; 261 #endif 262 263 kfree(ctrl_ref); 264 } 265 266 void ieee80211_check_rate_mask(struct ieee80211_sub_if_data *sdata) 267 { 268 struct ieee80211_local *local = sdata->local; 269 struct ieee80211_supported_band *sband; 270 u32 user_mask, basic_rates = sdata->vif.bss_conf.basic_rates; 271 enum nl80211_band band; 272 273 if (WARN_ON(!sdata->vif.bss_conf.chandef.chan)) 274 return; 275 276 if (WARN_ON_ONCE(!basic_rates)) 277 return; 278 279 band = sdata->vif.bss_conf.chandef.chan->band; 280 user_mask = sdata->rc_rateidx_mask[band]; 281 sband = local->hw.wiphy->bands[band]; 282 283 if (user_mask & basic_rates) 284 return; 285 286 sdata_dbg(sdata, 287 "no overlap between basic rates (0x%x) and user mask (0x%x on band %d) - clearing the latter", 288 basic_rates, user_mask, band); 289 sdata->rc_rateidx_mask[band] = (1 << sband->n_bitrates) - 1; 290 } 291 292 static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc) 293 { 294 struct sk_buff *skb = txrc->skb; 295 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 296 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 297 __le16 fc; 298 299 fc = hdr->frame_control; 300 301 return (info->flags & (IEEE80211_TX_CTL_NO_ACK | 302 IEEE80211_TX_CTL_USE_MINRATE)) || 303 !ieee80211_is_data(fc); 304 } 305 306 static void rc_send_low_basicrate(s8 *idx, u32 basic_rates, 307 struct ieee80211_supported_band *sband) 308 { 309 u8 i; 310 311 if (basic_rates == 0) 312 return; /* assume basic rates unknown and accept rate */ 313 if (*idx < 0) 314 return; 315 if (basic_rates & (1 << *idx)) 316 return; /* selected rate is a basic rate */ 317 318 for (i = *idx + 1; i <= sband->n_bitrates; i++) { 319 if (basic_rates & (1 << i)) { 320 *idx = i; 321 return; 322 } 323 } 324 325 /* could not find a basic rate; use original selection */ 326 } 327 328 static void __rate_control_send_low(struct ieee80211_hw *hw, 329 struct ieee80211_supported_band *sband, 330 struct ieee80211_sta *sta, 331 struct ieee80211_tx_info *info, 332 u32 rate_mask) 333 { 334 int i; 335 u32 rate_flags = 336 ieee80211_chandef_rate_flags(&hw->conf.chandef); 337 338 if ((sband->band == NL80211_BAND_2GHZ) && 339 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE)) 340 rate_flags |= IEEE80211_RATE_ERP_G; 341 342 info->control.rates[0].idx = 0; 343 for (i = 0; i < sband->n_bitrates; i++) { 344 if (!(rate_mask & BIT(i))) 345 continue; 346 347 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 348 continue; 349 350 if (!rate_supported(sta, sband->band, i)) 351 continue; 352 353 info->control.rates[0].idx = i; 354 break; 355 } 356 WARN_ONCE(i == sband->n_bitrates, 357 "no supported rates for sta %pM (0x%x, band %d) in rate_mask 0x%x with flags 0x%x\n", 358 sta ? sta->addr : NULL, 359 sta ? sta->supp_rates[sband->band] : -1, 360 sband->band, 361 rate_mask, rate_flags); 362 363 info->control.rates[0].count = 364 (info->flags & IEEE80211_TX_CTL_NO_ACK) ? 365 1 : hw->max_rate_tries; 366 367 info->control.skip_table = 1; 368 } 369 370 371 static bool rate_control_send_low(struct ieee80211_sta *pubsta, 372 struct ieee80211_tx_rate_control *txrc) 373 { 374 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 375 struct ieee80211_supported_band *sband = txrc->sband; 376 struct sta_info *sta; 377 int mcast_rate; 378 bool use_basicrate = false; 379 380 if (!pubsta || rc_no_data_or_no_ack_use_min(txrc)) { 381 __rate_control_send_low(txrc->hw, sband, pubsta, info, 382 txrc->rate_idx_mask); 383 384 if (!pubsta && txrc->bss) { 385 mcast_rate = txrc->bss_conf->mcast_rate[sband->band]; 386 if (mcast_rate > 0) { 387 info->control.rates[0].idx = mcast_rate - 1; 388 return true; 389 } 390 use_basicrate = true; 391 } else if (pubsta) { 392 sta = container_of(pubsta, struct sta_info, sta); 393 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) 394 use_basicrate = true; 395 } 396 397 if (use_basicrate) 398 rc_send_low_basicrate(&info->control.rates[0].idx, 399 txrc->bss_conf->basic_rates, 400 sband); 401 402 return true; 403 } 404 return false; 405 } 406 407 static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask) 408 { 409 int j; 410 411 /* See whether the selected rate or anything below it is allowed. */ 412 for (j = *rate_idx; j >= 0; j--) { 413 if (mask & (1 << j)) { 414 /* Okay, found a suitable rate. Use it. */ 415 *rate_idx = j; 416 return true; 417 } 418 } 419 420 /* Try to find a higher rate that would be allowed */ 421 for (j = *rate_idx + 1; j < n_bitrates; j++) { 422 if (mask & (1 << j)) { 423 /* Okay, found a suitable rate. Use it. */ 424 *rate_idx = j; 425 return true; 426 } 427 } 428 return false; 429 } 430 431 static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask) 432 { 433 int i, j; 434 int ridx, rbit; 435 436 ridx = *rate_idx / 8; 437 rbit = *rate_idx % 8; 438 439 /* sanity check */ 440 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN) 441 return false; 442 443 /* See whether the selected rate or anything below it is allowed. */ 444 for (i = ridx; i >= 0; i--) { 445 for (j = rbit; j >= 0; j--) 446 if (mcs_mask[i] & BIT(j)) { 447 *rate_idx = i * 8 + j; 448 return true; 449 } 450 rbit = 7; 451 } 452 453 /* Try to find a higher rate that would be allowed */ 454 ridx = (*rate_idx + 1) / 8; 455 rbit = (*rate_idx + 1) % 8; 456 457 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) { 458 for (j = rbit; j < 8; j++) 459 if (mcs_mask[i] & BIT(j)) { 460 *rate_idx = i * 8 + j; 461 return true; 462 } 463 rbit = 0; 464 } 465 return false; 466 } 467 468 static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask) 469 { 470 int i, j; 471 int ridx, rbit; 472 473 ridx = *rate_idx >> 4; 474 rbit = *rate_idx & 0xf; 475 476 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX) 477 return false; 478 479 /* See whether the selected rate or anything below it is allowed. */ 480 for (i = ridx; i >= 0; i--) { 481 for (j = rbit; j >= 0; j--) { 482 if (vht_mask[i] & BIT(j)) { 483 *rate_idx = (i << 4) | j; 484 return true; 485 } 486 } 487 rbit = 15; 488 } 489 490 /* Try to find a higher rate that would be allowed */ 491 ridx = (*rate_idx + 1) >> 4; 492 rbit = (*rate_idx + 1) & 0xf; 493 494 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) { 495 for (j = rbit; j < 16; j++) { 496 if (vht_mask[i] & BIT(j)) { 497 *rate_idx = (i << 4) | j; 498 return true; 499 } 500 } 501 rbit = 0; 502 } 503 return false; 504 } 505 506 static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags, 507 struct ieee80211_supported_band *sband, 508 enum nl80211_chan_width chan_width, 509 u32 mask, 510 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 511 u16 vht_mask[NL80211_VHT_NSS_MAX]) 512 { 513 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) { 514 /* handle VHT rates */ 515 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask)) 516 return; 517 518 *rate_idx = 0; 519 /* keep protection flags */ 520 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 521 IEEE80211_TX_RC_USE_CTS_PROTECT | 522 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 523 524 *rate_flags |= IEEE80211_TX_RC_MCS; 525 if (chan_width == NL80211_CHAN_WIDTH_40) 526 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 527 528 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 529 return; 530 531 /* also try the legacy rates. */ 532 *rate_flags &= ~(IEEE80211_TX_RC_MCS | 533 IEEE80211_TX_RC_40_MHZ_WIDTH); 534 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 535 mask)) 536 return; 537 } else if (*rate_flags & IEEE80211_TX_RC_MCS) { 538 /* handle HT rates */ 539 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 540 return; 541 542 /* also try the legacy rates. */ 543 *rate_idx = 0; 544 /* keep protection flags */ 545 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 546 IEEE80211_TX_RC_USE_CTS_PROTECT | 547 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 548 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 549 mask)) 550 return; 551 } else { 552 /* handle legacy rates */ 553 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 554 mask)) 555 return; 556 557 /* if HT BSS, and we handle a data frame, also try HT rates */ 558 switch (chan_width) { 559 case NL80211_CHAN_WIDTH_20_NOHT: 560 case NL80211_CHAN_WIDTH_5: 561 case NL80211_CHAN_WIDTH_10: 562 return; 563 default: 564 break; 565 } 566 567 *rate_idx = 0; 568 /* keep protection flags */ 569 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 570 IEEE80211_TX_RC_USE_CTS_PROTECT | 571 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 572 573 *rate_flags |= IEEE80211_TX_RC_MCS; 574 575 if (chan_width == NL80211_CHAN_WIDTH_40) 576 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 577 578 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 579 return; 580 } 581 582 /* 583 * Uh.. No suitable rate exists. This should not really happen with 584 * sane TX rate mask configurations. However, should someone manage to 585 * configure supported rates and TX rate mask in incompatible way, 586 * allow the frame to be transmitted with whatever the rate control 587 * selected. 588 */ 589 } 590 591 static void rate_fixup_ratelist(struct ieee80211_vif *vif, 592 struct ieee80211_supported_band *sband, 593 struct ieee80211_tx_info *info, 594 struct ieee80211_tx_rate *rates, 595 int max_rates) 596 { 597 struct ieee80211_rate *rate; 598 bool inval = false; 599 int i; 600 601 /* 602 * Set up the RTS/CTS rate as the fastest basic rate 603 * that is not faster than the data rate unless there 604 * is no basic rate slower than the data rate, in which 605 * case we pick the slowest basic rate 606 * 607 * XXX: Should this check all retry rates? 608 */ 609 if (!(rates[0].flags & 610 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) { 611 u32 basic_rates = vif->bss_conf.basic_rates; 612 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0; 613 614 rate = &sband->bitrates[rates[0].idx]; 615 616 for (i = 0; i < sband->n_bitrates; i++) { 617 /* must be a basic rate */ 618 if (!(basic_rates & BIT(i))) 619 continue; 620 /* must not be faster than the data rate */ 621 if (sband->bitrates[i].bitrate > rate->bitrate) 622 continue; 623 /* maximum */ 624 if (sband->bitrates[baserate].bitrate < 625 sband->bitrates[i].bitrate) 626 baserate = i; 627 } 628 629 info->control.rts_cts_rate_idx = baserate; 630 } 631 632 for (i = 0; i < max_rates; i++) { 633 /* 634 * make sure there's no valid rate following 635 * an invalid one, just in case drivers don't 636 * take the API seriously to stop at -1. 637 */ 638 if (inval) { 639 rates[i].idx = -1; 640 continue; 641 } 642 if (rates[i].idx < 0) { 643 inval = true; 644 continue; 645 } 646 647 /* 648 * For now assume MCS is already set up correctly, this 649 * needs to be fixed. 650 */ 651 if (rates[i].flags & IEEE80211_TX_RC_MCS) { 652 WARN_ON(rates[i].idx > 76); 653 654 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 655 info->control.use_cts_prot) 656 rates[i].flags |= 657 IEEE80211_TX_RC_USE_CTS_PROTECT; 658 continue; 659 } 660 661 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) { 662 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9); 663 continue; 664 } 665 666 /* set up RTS protection if desired */ 667 if (info->control.use_rts) { 668 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS; 669 info->control.use_cts_prot = false; 670 } 671 672 /* RC is busted */ 673 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) { 674 rates[i].idx = -1; 675 continue; 676 } 677 678 rate = &sband->bitrates[rates[i].idx]; 679 680 /* set up short preamble */ 681 if (info->control.short_preamble && 682 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 683 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 684 685 /* set up G protection */ 686 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 687 info->control.use_cts_prot && 688 rate->flags & IEEE80211_RATE_ERP_G) 689 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT; 690 } 691 } 692 693 694 static void rate_control_fill_sta_table(struct ieee80211_sta *sta, 695 struct ieee80211_tx_info *info, 696 struct ieee80211_tx_rate *rates, 697 int max_rates) 698 { 699 struct ieee80211_sta_rates *ratetbl = NULL; 700 int i; 701 702 if (sta && !info->control.skip_table) 703 ratetbl = rcu_dereference(sta->rates); 704 705 /* Fill remaining rate slots with data from the sta rate table. */ 706 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE); 707 for (i = 0; i < max_rates; i++) { 708 if (i < ARRAY_SIZE(info->control.rates) && 709 info->control.rates[i].idx >= 0 && 710 info->control.rates[i].count) { 711 if (rates != info->control.rates) 712 rates[i] = info->control.rates[i]; 713 } else if (ratetbl) { 714 rates[i].idx = ratetbl->rate[i].idx; 715 rates[i].flags = ratetbl->rate[i].flags; 716 if (info->control.use_rts) 717 rates[i].count = ratetbl->rate[i].count_rts; 718 else if (info->control.use_cts_prot) 719 rates[i].count = ratetbl->rate[i].count_cts; 720 else 721 rates[i].count = ratetbl->rate[i].count; 722 } else { 723 rates[i].idx = -1; 724 rates[i].count = 0; 725 } 726 727 if (rates[i].idx < 0 || !rates[i].count) 728 break; 729 } 730 } 731 732 static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata, 733 struct ieee80211_supported_band *sband, 734 struct ieee80211_sta *sta, u32 *mask, 735 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 736 u16 vht_mask[NL80211_VHT_NSS_MAX]) 737 { 738 u32 i, flags; 739 740 *mask = sdata->rc_rateidx_mask[sband->band]; 741 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef); 742 for (i = 0; i < sband->n_bitrates; i++) { 743 if ((flags & sband->bitrates[i].flags) != flags) 744 *mask &= ~BIT(i); 745 } 746 747 if (*mask == (1 << sband->n_bitrates) - 1 && 748 !sdata->rc_has_mcs_mask[sband->band] && 749 !sdata->rc_has_vht_mcs_mask[sband->band]) 750 return false; 751 752 if (sdata->rc_has_mcs_mask[sband->band]) 753 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band], 754 IEEE80211_HT_MCS_MASK_LEN); 755 else 756 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN); 757 758 if (sdata->rc_has_vht_mcs_mask[sband->band]) 759 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band], 760 sizeof(u16) * NL80211_VHT_NSS_MAX); 761 else 762 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX); 763 764 if (sta) { 765 __le16 sta_vht_cap; 766 u16 sta_vht_mask[NL80211_VHT_NSS_MAX]; 767 768 /* Filter out rates that the STA does not support */ 769 *mask &= sta->supp_rates[sband->band]; 770 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) 771 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i]; 772 773 sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map; 774 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask); 775 for (i = 0; i < NL80211_VHT_NSS_MAX; i++) 776 vht_mask[i] &= sta_vht_mask[i]; 777 } 778 779 return true; 780 } 781 782 static void 783 rate_control_apply_mask_ratetbl(struct sta_info *sta, 784 struct ieee80211_supported_band *sband, 785 struct ieee80211_sta_rates *rates) 786 { 787 int i; 788 u32 mask; 789 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 790 u16 vht_mask[NL80211_VHT_NSS_MAX]; 791 enum nl80211_chan_width chan_width; 792 793 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask, 794 mcs_mask, vht_mask)) 795 return; 796 797 chan_width = sta->sdata->vif.bss_conf.chandef.width; 798 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) { 799 if (rates->rate[i].idx < 0) 800 break; 801 802 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags, 803 sband, chan_width, mask, mcs_mask, 804 vht_mask); 805 } 806 } 807 808 static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata, 809 struct ieee80211_sta *sta, 810 struct ieee80211_supported_band *sband, 811 struct ieee80211_tx_rate *rates, 812 int max_rates) 813 { 814 enum nl80211_chan_width chan_width; 815 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 816 u32 mask; 817 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX]; 818 int i; 819 820 /* 821 * Try to enforce the rateidx mask the user wanted. skip this if the 822 * default mask (allow all rates) is used to save some processing for 823 * the common case. 824 */ 825 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask, 826 vht_mask)) 827 return; 828 829 /* 830 * Make sure the rate index selected for each TX rate is 831 * included in the configured mask and change the rate indexes 832 * if needed. 833 */ 834 chan_width = sdata->vif.bss_conf.chandef.width; 835 for (i = 0; i < max_rates; i++) { 836 /* Skip invalid rates */ 837 if (rates[i].idx < 0) 838 break; 839 840 rate_flags = rates[i].flags; 841 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband, 842 chan_width, mask, mcs_mask, vht_mask); 843 rates[i].flags = rate_flags; 844 } 845 } 846 847 void ieee80211_get_tx_rates(struct ieee80211_vif *vif, 848 struct ieee80211_sta *sta, 849 struct sk_buff *skb, 850 struct ieee80211_tx_rate *dest, 851 int max_rates) 852 { 853 struct ieee80211_sub_if_data *sdata; 854 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 855 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 856 struct ieee80211_supported_band *sband; 857 858 rate_control_fill_sta_table(sta, info, dest, max_rates); 859 860 if (!vif) 861 return; 862 863 sdata = vif_to_sdata(vif); 864 sband = sdata->local->hw.wiphy->bands[info->band]; 865 866 if (ieee80211_is_data(hdr->frame_control)) 867 rate_control_apply_mask(sdata, sta, sband, dest, max_rates); 868 869 if (dest[0].idx < 0) 870 __rate_control_send_low(&sdata->local->hw, sband, sta, info, 871 sdata->rc_rateidx_mask[info->band]); 872 873 if (sta) 874 rate_fixup_ratelist(vif, sband, info, dest, max_rates); 875 } 876 EXPORT_SYMBOL(ieee80211_get_tx_rates); 877 878 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, 879 struct sta_info *sta, 880 struct ieee80211_tx_rate_control *txrc) 881 { 882 struct rate_control_ref *ref = sdata->local->rate_ctrl; 883 void *priv_sta = NULL; 884 struct ieee80211_sta *ista = NULL; 885 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 886 int i; 887 888 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 889 info->control.rates[i].idx = -1; 890 info->control.rates[i].flags = 0; 891 info->control.rates[i].count = 0; 892 } 893 894 if (rate_control_send_low(sta ? &sta->sta : NULL, txrc)) 895 return; 896 897 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL)) 898 return; 899 900 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) { 901 ista = &sta->sta; 902 priv_sta = sta->rate_ctrl_priv; 903 } 904 905 if (ista) { 906 spin_lock_bh(&sta->rate_ctrl_lock); 907 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); 908 spin_unlock_bh(&sta->rate_ctrl_lock); 909 } else { 910 rate_control_send_low(NULL, txrc); 911 } 912 913 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE)) 914 return; 915 916 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb, 917 info->control.rates, 918 ARRAY_SIZE(info->control.rates)); 919 } 920 921 int rate_control_set_rates(struct ieee80211_hw *hw, 922 struct ieee80211_sta *pubsta, 923 struct ieee80211_sta_rates *rates) 924 { 925 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 926 struct ieee80211_sta_rates *old; 927 struct ieee80211_supported_band *sband; 928 929 sband = ieee80211_get_sband(sta->sdata); 930 if (!sband) 931 return -EINVAL; 932 rate_control_apply_mask_ratetbl(sta, sband, rates); 933 /* 934 * mac80211 guarantees that this function will not be called 935 * concurrently, so the following RCU access is safe, even without 936 * extra locking. This can not be checked easily, so we just set 937 * the condition to true. 938 */ 939 old = rcu_dereference_protected(pubsta->rates, true); 940 rcu_assign_pointer(pubsta->rates, rates); 941 if (old) 942 kfree_rcu(old, rcu_head); 943 944 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta); 945 946 ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta)); 947 948 return 0; 949 } 950 EXPORT_SYMBOL(rate_control_set_rates); 951 952 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, 953 const char *name) 954 { 955 struct rate_control_ref *ref; 956 957 ASSERT_RTNL(); 958 959 if (local->open_count) 960 return -EBUSY; 961 962 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) { 963 if (WARN_ON(!local->ops->set_rts_threshold)) 964 return -EINVAL; 965 return 0; 966 } 967 968 ref = rate_control_alloc(name, local); 969 if (!ref) { 970 wiphy_warn(local->hw.wiphy, 971 "Failed to select rate control algorithm\n"); 972 return -ENOENT; 973 } 974 975 WARN_ON(local->rate_ctrl); 976 local->rate_ctrl = ref; 977 978 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", 979 ref->ops->name); 980 981 return 0; 982 } 983 984 void rate_control_deinitialize(struct ieee80211_local *local) 985 { 986 struct rate_control_ref *ref; 987 988 ref = local->rate_ctrl; 989 990 if (!ref) 991 return; 992 993 local->rate_ctrl = NULL; 994 rate_control_free(local, ref); 995 } 996