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 * Copyright 2017 Intel Deutschland GmbH 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/rtnetlink.h> 14 #include <linux/module.h> 15 #include <linux/slab.h> 16 #include "rate.h" 17 #include "ieee80211_i.h" 18 #include "debugfs.h" 19 20 struct rate_control_alg { 21 struct list_head list; 22 const struct rate_control_ops *ops; 23 }; 24 25 static LIST_HEAD(rate_ctrl_algs); 26 static DEFINE_MUTEX(rate_ctrl_mutex); 27 28 static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT; 29 module_param(ieee80211_default_rc_algo, charp, 0644); 30 MODULE_PARM_DESC(ieee80211_default_rc_algo, 31 "Default rate control algorithm for mac80211 to use"); 32 33 void rate_control_rate_init(struct sta_info *sta) 34 { 35 struct ieee80211_local *local = sta->sdata->local; 36 struct rate_control_ref *ref = sta->rate_ctrl; 37 struct ieee80211_sta *ista = &sta->sta; 38 void *priv_sta = sta->rate_ctrl_priv; 39 struct ieee80211_supported_band *sband; 40 struct ieee80211_chanctx_conf *chanctx_conf; 41 42 ieee80211_sta_set_rx_nss(sta); 43 44 if (!ref) 45 return; 46 47 rcu_read_lock(); 48 49 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf); 50 if (WARN_ON(!chanctx_conf)) { 51 rcu_read_unlock(); 52 return; 53 } 54 55 sband = local->hw.wiphy->bands[chanctx_conf->def.chan->band]; 56 57 spin_lock_bh(&sta->rate_ctrl_lock); 58 ref->ops->rate_init(ref->priv, sband, &chanctx_conf->def, ista, 59 priv_sta); 60 spin_unlock_bh(&sta->rate_ctrl_lock); 61 rcu_read_unlock(); 62 set_sta_flag(sta, WLAN_STA_RATE_CONTROL); 63 } 64 65 void rate_control_tx_status(struct ieee80211_local *local, 66 struct ieee80211_supported_band *sband, 67 struct ieee80211_tx_status *st) 68 { 69 struct rate_control_ref *ref = local->rate_ctrl; 70 struct sta_info *sta = container_of(st->sta, struct sta_info, sta); 71 void *priv_sta = sta->rate_ctrl_priv; 72 73 if (!ref || !test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) 74 return; 75 76 spin_lock_bh(&sta->rate_ctrl_lock); 77 if (ref->ops->tx_status_ext) 78 ref->ops->tx_status_ext(ref->priv, sband, priv_sta, st); 79 else if (st->skb) 80 ref->ops->tx_status(ref->priv, sband, st->sta, priv_sta, st->skb); 81 else 82 WARN_ON_ONCE(1); 83 84 spin_unlock_bh(&sta->rate_ctrl_lock); 85 } 86 87 void rate_control_rate_update(struct ieee80211_local *local, 88 struct ieee80211_supported_band *sband, 89 struct sta_info *sta, u32 changed) 90 { 91 struct rate_control_ref *ref = local->rate_ctrl; 92 struct ieee80211_sta *ista = &sta->sta; 93 void *priv_sta = sta->rate_ctrl_priv; 94 struct ieee80211_chanctx_conf *chanctx_conf; 95 96 if (ref && ref->ops->rate_update) { 97 rcu_read_lock(); 98 99 chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf); 100 if (WARN_ON(!chanctx_conf)) { 101 rcu_read_unlock(); 102 return; 103 } 104 105 spin_lock_bh(&sta->rate_ctrl_lock); 106 ref->ops->rate_update(ref->priv, sband, &chanctx_conf->def, 107 ista, priv_sta, changed); 108 spin_unlock_bh(&sta->rate_ctrl_lock); 109 rcu_read_unlock(); 110 } 111 drv_sta_rc_update(local, sta->sdata, &sta->sta, changed); 112 } 113 114 int ieee80211_rate_control_register(const struct rate_control_ops *ops) 115 { 116 struct rate_control_alg *alg; 117 118 if (!ops->name) 119 return -EINVAL; 120 121 mutex_lock(&rate_ctrl_mutex); 122 list_for_each_entry(alg, &rate_ctrl_algs, list) { 123 if (!strcmp(alg->ops->name, ops->name)) { 124 /* don't register an algorithm twice */ 125 WARN_ON(1); 126 mutex_unlock(&rate_ctrl_mutex); 127 return -EALREADY; 128 } 129 } 130 131 alg = kzalloc(sizeof(*alg), GFP_KERNEL); 132 if (alg == NULL) { 133 mutex_unlock(&rate_ctrl_mutex); 134 return -ENOMEM; 135 } 136 alg->ops = ops; 137 138 list_add_tail(&alg->list, &rate_ctrl_algs); 139 mutex_unlock(&rate_ctrl_mutex); 140 141 return 0; 142 } 143 EXPORT_SYMBOL(ieee80211_rate_control_register); 144 145 void ieee80211_rate_control_unregister(const struct rate_control_ops *ops) 146 { 147 struct rate_control_alg *alg; 148 149 mutex_lock(&rate_ctrl_mutex); 150 list_for_each_entry(alg, &rate_ctrl_algs, list) { 151 if (alg->ops == ops) { 152 list_del(&alg->list); 153 kfree(alg); 154 break; 155 } 156 } 157 mutex_unlock(&rate_ctrl_mutex); 158 } 159 EXPORT_SYMBOL(ieee80211_rate_control_unregister); 160 161 static const struct rate_control_ops * 162 ieee80211_try_rate_control_ops_get(const char *name) 163 { 164 struct rate_control_alg *alg; 165 const struct rate_control_ops *ops = NULL; 166 167 if (!name) 168 return NULL; 169 170 mutex_lock(&rate_ctrl_mutex); 171 list_for_each_entry(alg, &rate_ctrl_algs, list) { 172 if (!strcmp(alg->ops->name, name)) { 173 ops = alg->ops; 174 break; 175 } 176 } 177 mutex_unlock(&rate_ctrl_mutex); 178 return ops; 179 } 180 181 /* Get the rate control algorithm. */ 182 static const struct rate_control_ops * 183 ieee80211_rate_control_ops_get(const char *name) 184 { 185 const struct rate_control_ops *ops; 186 const char *alg_name; 187 188 kernel_param_lock(THIS_MODULE); 189 if (!name) 190 alg_name = ieee80211_default_rc_algo; 191 else 192 alg_name = name; 193 194 ops = ieee80211_try_rate_control_ops_get(alg_name); 195 if (!ops && name) 196 /* try default if specific alg requested but not found */ 197 ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo); 198 199 /* Note: check for > 0 is intentional to avoid clang warning */ 200 if (!ops && (strlen(CONFIG_MAC80211_RC_DEFAULT) > 0)) 201 /* try built-in one if specific alg requested but not found */ 202 ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT); 203 204 kernel_param_unlock(THIS_MODULE); 205 206 return ops; 207 } 208 209 #ifdef CONFIG_MAC80211_DEBUGFS 210 static ssize_t rcname_read(struct file *file, char __user *userbuf, 211 size_t count, loff_t *ppos) 212 { 213 struct rate_control_ref *ref = file->private_data; 214 int len = strlen(ref->ops->name); 215 216 return simple_read_from_buffer(userbuf, count, ppos, 217 ref->ops->name, len); 218 } 219 220 static const struct file_operations rcname_ops = { 221 .read = rcname_read, 222 .open = simple_open, 223 .llseek = default_llseek, 224 }; 225 #endif 226 227 static struct rate_control_ref *rate_control_alloc(const char *name, 228 struct ieee80211_local *local) 229 { 230 struct dentry *debugfsdir = NULL; 231 struct rate_control_ref *ref; 232 233 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL); 234 if (!ref) 235 return NULL; 236 ref->ops = ieee80211_rate_control_ops_get(name); 237 if (!ref->ops) 238 goto free; 239 240 #ifdef CONFIG_MAC80211_DEBUGFS 241 debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir); 242 local->debugfs.rcdir = debugfsdir; 243 debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops); 244 #endif 245 246 ref->priv = ref->ops->alloc(&local->hw, debugfsdir); 247 if (!ref->priv) 248 goto free; 249 return ref; 250 251 free: 252 kfree(ref); 253 return NULL; 254 } 255 256 static void rate_control_free(struct ieee80211_local *local, 257 struct rate_control_ref *ctrl_ref) 258 { 259 ctrl_ref->ops->free(ctrl_ref->priv); 260 261 #ifdef CONFIG_MAC80211_DEBUGFS 262 debugfs_remove_recursive(local->debugfs.rcdir); 263 local->debugfs.rcdir = NULL; 264 #endif 265 266 kfree(ctrl_ref); 267 } 268 269 void ieee80211_check_rate_mask(struct ieee80211_sub_if_data *sdata) 270 { 271 struct ieee80211_local *local = sdata->local; 272 struct ieee80211_supported_band *sband; 273 u32 user_mask, basic_rates = sdata->vif.bss_conf.basic_rates; 274 enum nl80211_band band; 275 276 if (WARN_ON(!sdata->vif.bss_conf.chandef.chan)) 277 return; 278 279 if (WARN_ON_ONCE(!basic_rates)) 280 return; 281 282 band = sdata->vif.bss_conf.chandef.chan->band; 283 user_mask = sdata->rc_rateidx_mask[band]; 284 sband = local->hw.wiphy->bands[band]; 285 286 if (user_mask & basic_rates) 287 return; 288 289 sdata_dbg(sdata, 290 "no overlap between basic rates (0x%x) and user mask (0x%x on band %d) - clearing the latter", 291 basic_rates, user_mask, band); 292 sdata->rc_rateidx_mask[band] = (1 << sband->n_bitrates) - 1; 293 } 294 295 static bool rc_no_data_or_no_ack_use_min(struct ieee80211_tx_rate_control *txrc) 296 { 297 struct sk_buff *skb = txrc->skb; 298 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 299 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 300 __le16 fc; 301 302 fc = hdr->frame_control; 303 304 return (info->flags & (IEEE80211_TX_CTL_NO_ACK | 305 IEEE80211_TX_CTL_USE_MINRATE)) || 306 !ieee80211_is_data(fc); 307 } 308 309 static void rc_send_low_basicrate(s8 *idx, u32 basic_rates, 310 struct ieee80211_supported_band *sband) 311 { 312 u8 i; 313 314 if (basic_rates == 0) 315 return; /* assume basic rates unknown and accept rate */ 316 if (*idx < 0) 317 return; 318 if (basic_rates & (1 << *idx)) 319 return; /* selected rate is a basic rate */ 320 321 for (i = *idx + 1; i <= sband->n_bitrates; i++) { 322 if (basic_rates & (1 << i)) { 323 *idx = i; 324 return; 325 } 326 } 327 328 /* could not find a basic rate; use original selection */ 329 } 330 331 static void __rate_control_send_low(struct ieee80211_hw *hw, 332 struct ieee80211_supported_band *sband, 333 struct ieee80211_sta *sta, 334 struct ieee80211_tx_info *info, 335 u32 rate_mask) 336 { 337 int i; 338 u32 rate_flags = 339 ieee80211_chandef_rate_flags(&hw->conf.chandef); 340 341 if ((sband->band == NL80211_BAND_2GHZ) && 342 (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE)) 343 rate_flags |= IEEE80211_RATE_ERP_G; 344 345 info->control.rates[0].idx = 0; 346 for (i = 0; i < sband->n_bitrates; i++) { 347 if (!(rate_mask & BIT(i))) 348 continue; 349 350 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 351 continue; 352 353 if (!rate_supported(sta, sband->band, i)) 354 continue; 355 356 info->control.rates[0].idx = i; 357 break; 358 } 359 WARN_ONCE(i == sband->n_bitrates, 360 "no supported rates (0x%x) in rate_mask 0x%x with flags 0x%x\n", 361 sta ? sta->supp_rates[sband->band] : -1, 362 rate_mask, rate_flags); 363 364 info->control.rates[0].count = 365 (info->flags & IEEE80211_TX_CTL_NO_ACK) ? 366 1 : hw->max_rate_tries; 367 368 info->control.skip_table = 1; 369 } 370 371 372 static bool rate_control_send_low(struct ieee80211_sta *pubsta, 373 struct ieee80211_tx_rate_control *txrc) 374 { 375 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 376 struct ieee80211_supported_band *sband = txrc->sband; 377 struct sta_info *sta; 378 int mcast_rate; 379 bool use_basicrate = false; 380 381 if (!pubsta || rc_no_data_or_no_ack_use_min(txrc)) { 382 __rate_control_send_low(txrc->hw, sband, pubsta, info, 383 txrc->rate_idx_mask); 384 385 if (!pubsta && txrc->bss) { 386 mcast_rate = txrc->bss_conf->mcast_rate[sband->band]; 387 if (mcast_rate > 0) { 388 info->control.rates[0].idx = mcast_rate - 1; 389 return true; 390 } 391 use_basicrate = true; 392 } else if (pubsta) { 393 sta = container_of(pubsta, struct sta_info, sta); 394 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) 395 use_basicrate = true; 396 } 397 398 if (use_basicrate) 399 rc_send_low_basicrate(&info->control.rates[0].idx, 400 txrc->bss_conf->basic_rates, 401 sband); 402 403 return true; 404 } 405 return false; 406 } 407 408 static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask) 409 { 410 int j; 411 412 /* See whether the selected rate or anything below it is allowed. */ 413 for (j = *rate_idx; j >= 0; j--) { 414 if (mask & (1 << j)) { 415 /* Okay, found a suitable rate. Use it. */ 416 *rate_idx = j; 417 return true; 418 } 419 } 420 421 /* Try to find a higher rate that would be allowed */ 422 for (j = *rate_idx + 1; j < n_bitrates; j++) { 423 if (mask & (1 << j)) { 424 /* Okay, found a suitable rate. Use it. */ 425 *rate_idx = j; 426 return true; 427 } 428 } 429 return false; 430 } 431 432 static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask) 433 { 434 int i, j; 435 int ridx, rbit; 436 437 ridx = *rate_idx / 8; 438 rbit = *rate_idx % 8; 439 440 /* sanity check */ 441 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN) 442 return false; 443 444 /* See whether the selected rate or anything below it is allowed. */ 445 for (i = ridx; i >= 0; i--) { 446 for (j = rbit; j >= 0; j--) 447 if (mcs_mask[i] & BIT(j)) { 448 *rate_idx = i * 8 + j; 449 return true; 450 } 451 rbit = 7; 452 } 453 454 /* Try to find a higher rate that would be allowed */ 455 ridx = (*rate_idx + 1) / 8; 456 rbit = (*rate_idx + 1) % 8; 457 458 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) { 459 for (j = rbit; j < 8; j++) 460 if (mcs_mask[i] & BIT(j)) { 461 *rate_idx = i * 8 + j; 462 return true; 463 } 464 rbit = 0; 465 } 466 return false; 467 } 468 469 static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask) 470 { 471 int i, j; 472 int ridx, rbit; 473 474 ridx = *rate_idx >> 4; 475 rbit = *rate_idx & 0xf; 476 477 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX) 478 return false; 479 480 /* See whether the selected rate or anything below it is allowed. */ 481 for (i = ridx; i >= 0; i--) { 482 for (j = rbit; j >= 0; j--) { 483 if (vht_mask[i] & BIT(j)) { 484 *rate_idx = (i << 4) | j; 485 return true; 486 } 487 } 488 rbit = 15; 489 } 490 491 /* Try to find a higher rate that would be allowed */ 492 ridx = (*rate_idx + 1) >> 4; 493 rbit = (*rate_idx + 1) & 0xf; 494 495 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) { 496 for (j = rbit; j < 16; j++) { 497 if (vht_mask[i] & BIT(j)) { 498 *rate_idx = (i << 4) | j; 499 return true; 500 } 501 } 502 rbit = 0; 503 } 504 return false; 505 } 506 507 static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags, 508 struct ieee80211_supported_band *sband, 509 enum nl80211_chan_width chan_width, 510 u32 mask, 511 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 512 u16 vht_mask[NL80211_VHT_NSS_MAX]) 513 { 514 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) { 515 /* handle VHT rates */ 516 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask)) 517 return; 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 if (chan_width == NL80211_CHAN_WIDTH_40) 527 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 528 529 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 530 return; 531 532 /* also try the legacy rates. */ 533 *rate_flags &= ~(IEEE80211_TX_RC_MCS | 534 IEEE80211_TX_RC_40_MHZ_WIDTH); 535 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 536 mask)) 537 return; 538 } else if (*rate_flags & IEEE80211_TX_RC_MCS) { 539 /* handle HT rates */ 540 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 541 return; 542 543 /* also try the legacy rates. */ 544 *rate_idx = 0; 545 /* keep protection flags */ 546 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 547 IEEE80211_TX_RC_USE_CTS_PROTECT | 548 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 549 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 550 mask)) 551 return; 552 } else { 553 /* handle legacy rates */ 554 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 555 mask)) 556 return; 557 558 /* if HT BSS, and we handle a data frame, also try HT rates */ 559 switch (chan_width) { 560 case NL80211_CHAN_WIDTH_20_NOHT: 561 case NL80211_CHAN_WIDTH_5: 562 case NL80211_CHAN_WIDTH_10: 563 return; 564 default: 565 break; 566 } 567 568 *rate_idx = 0; 569 /* keep protection flags */ 570 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 571 IEEE80211_TX_RC_USE_CTS_PROTECT | 572 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 573 574 *rate_flags |= IEEE80211_TX_RC_MCS; 575 576 if (chan_width == NL80211_CHAN_WIDTH_40) 577 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 578 579 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 580 return; 581 } 582 583 /* 584 * Uh.. No suitable rate exists. This should not really happen with 585 * sane TX rate mask configurations. However, should someone manage to 586 * configure supported rates and TX rate mask in incompatible way, 587 * allow the frame to be transmitted with whatever the rate control 588 * selected. 589 */ 590 } 591 592 static void rate_fixup_ratelist(struct ieee80211_vif *vif, 593 struct ieee80211_supported_band *sband, 594 struct ieee80211_tx_info *info, 595 struct ieee80211_tx_rate *rates, 596 int max_rates) 597 { 598 struct ieee80211_rate *rate; 599 bool inval = false; 600 int i; 601 602 /* 603 * Set up the RTS/CTS rate as the fastest basic rate 604 * that is not faster than the data rate unless there 605 * is no basic rate slower than the data rate, in which 606 * case we pick the slowest basic rate 607 * 608 * XXX: Should this check all retry rates? 609 */ 610 if (!(rates[0].flags & 611 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) { 612 u32 basic_rates = vif->bss_conf.basic_rates; 613 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0; 614 615 rate = &sband->bitrates[rates[0].idx]; 616 617 for (i = 0; i < sband->n_bitrates; i++) { 618 /* must be a basic rate */ 619 if (!(basic_rates & BIT(i))) 620 continue; 621 /* must not be faster than the data rate */ 622 if (sband->bitrates[i].bitrate > rate->bitrate) 623 continue; 624 /* maximum */ 625 if (sband->bitrates[baserate].bitrate < 626 sband->bitrates[i].bitrate) 627 baserate = i; 628 } 629 630 info->control.rts_cts_rate_idx = baserate; 631 } 632 633 for (i = 0; i < max_rates; i++) { 634 /* 635 * make sure there's no valid rate following 636 * an invalid one, just in case drivers don't 637 * take the API seriously to stop at -1. 638 */ 639 if (inval) { 640 rates[i].idx = -1; 641 continue; 642 } 643 if (rates[i].idx < 0) { 644 inval = true; 645 continue; 646 } 647 648 /* 649 * For now assume MCS is already set up correctly, this 650 * needs to be fixed. 651 */ 652 if (rates[i].flags & IEEE80211_TX_RC_MCS) { 653 WARN_ON(rates[i].idx > 76); 654 655 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 656 info->control.use_cts_prot) 657 rates[i].flags |= 658 IEEE80211_TX_RC_USE_CTS_PROTECT; 659 continue; 660 } 661 662 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) { 663 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9); 664 continue; 665 } 666 667 /* set up RTS protection if desired */ 668 if (info->control.use_rts) { 669 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS; 670 info->control.use_cts_prot = false; 671 } 672 673 /* RC is busted */ 674 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) { 675 rates[i].idx = -1; 676 continue; 677 } 678 679 rate = &sband->bitrates[rates[i].idx]; 680 681 /* set up short preamble */ 682 if (info->control.short_preamble && 683 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 684 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 685 686 /* set up G protection */ 687 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 688 info->control.use_cts_prot && 689 rate->flags & IEEE80211_RATE_ERP_G) 690 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT; 691 } 692 } 693 694 695 static void rate_control_fill_sta_table(struct ieee80211_sta *sta, 696 struct ieee80211_tx_info *info, 697 struct ieee80211_tx_rate *rates, 698 int max_rates) 699 { 700 struct ieee80211_sta_rates *ratetbl = NULL; 701 int i; 702 703 if (sta && !info->control.skip_table) 704 ratetbl = rcu_dereference(sta->rates); 705 706 /* Fill remaining rate slots with data from the sta rate table. */ 707 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE); 708 for (i = 0; i < max_rates; i++) { 709 if (i < ARRAY_SIZE(info->control.rates) && 710 info->control.rates[i].idx >= 0 && 711 info->control.rates[i].count) { 712 if (rates != info->control.rates) 713 rates[i] = info->control.rates[i]; 714 } else if (ratetbl) { 715 rates[i].idx = ratetbl->rate[i].idx; 716 rates[i].flags = ratetbl->rate[i].flags; 717 if (info->control.use_rts) 718 rates[i].count = ratetbl->rate[i].count_rts; 719 else if (info->control.use_cts_prot) 720 rates[i].count = ratetbl->rate[i].count_cts; 721 else 722 rates[i].count = ratetbl->rate[i].count; 723 } else { 724 rates[i].idx = -1; 725 rates[i].count = 0; 726 } 727 728 if (rates[i].idx < 0 || !rates[i].count) 729 break; 730 } 731 } 732 733 static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata, 734 struct ieee80211_supported_band *sband, 735 struct ieee80211_sta *sta, u32 *mask, 736 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 737 u16 vht_mask[NL80211_VHT_NSS_MAX]) 738 { 739 u32 i, flags; 740 741 *mask = sdata->rc_rateidx_mask[sband->band]; 742 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef); 743 for (i = 0; i < sband->n_bitrates; i++) { 744 if ((flags & sband->bitrates[i].flags) != flags) 745 *mask &= ~BIT(i); 746 } 747 748 if (*mask == (1 << sband->n_bitrates) - 1 && 749 !sdata->rc_has_mcs_mask[sband->band] && 750 !sdata->rc_has_vht_mcs_mask[sband->band]) 751 return false; 752 753 if (sdata->rc_has_mcs_mask[sband->band]) 754 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band], 755 IEEE80211_HT_MCS_MASK_LEN); 756 else 757 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN); 758 759 if (sdata->rc_has_vht_mcs_mask[sband->band]) 760 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band], 761 sizeof(u16) * NL80211_VHT_NSS_MAX); 762 else 763 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX); 764 765 if (sta) { 766 __le16 sta_vht_cap; 767 u16 sta_vht_mask[NL80211_VHT_NSS_MAX]; 768 769 /* Filter out rates that the STA does not support */ 770 *mask &= sta->supp_rates[sband->band]; 771 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) 772 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i]; 773 774 sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map; 775 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask); 776 for (i = 0; i < NL80211_VHT_NSS_MAX; i++) 777 vht_mask[i] &= sta_vht_mask[i]; 778 } 779 780 return true; 781 } 782 783 static void 784 rate_control_apply_mask_ratetbl(struct sta_info *sta, 785 struct ieee80211_supported_band *sband, 786 struct ieee80211_sta_rates *rates) 787 { 788 int i; 789 u32 mask; 790 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 791 u16 vht_mask[NL80211_VHT_NSS_MAX]; 792 enum nl80211_chan_width chan_width; 793 794 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask, 795 mcs_mask, vht_mask)) 796 return; 797 798 chan_width = sta->sdata->vif.bss_conf.chandef.width; 799 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) { 800 if (rates->rate[i].idx < 0) 801 break; 802 803 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags, 804 sband, chan_width, mask, mcs_mask, 805 vht_mask); 806 } 807 } 808 809 static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata, 810 struct ieee80211_sta *sta, 811 struct ieee80211_supported_band *sband, 812 struct ieee80211_tx_rate *rates, 813 int max_rates) 814 { 815 enum nl80211_chan_width chan_width; 816 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 817 u32 mask; 818 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX]; 819 int i; 820 821 /* 822 * Try to enforce the rateidx mask the user wanted. skip this if the 823 * default mask (allow all rates) is used to save some processing for 824 * the common case. 825 */ 826 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask, 827 vht_mask)) 828 return; 829 830 /* 831 * Make sure the rate index selected for each TX rate is 832 * included in the configured mask and change the rate indexes 833 * if needed. 834 */ 835 chan_width = sdata->vif.bss_conf.chandef.width; 836 for (i = 0; i < max_rates; i++) { 837 /* Skip invalid rates */ 838 if (rates[i].idx < 0) 839 break; 840 841 rate_flags = rates[i].flags; 842 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband, 843 chan_width, mask, mcs_mask, vht_mask); 844 rates[i].flags = rate_flags; 845 } 846 } 847 848 void ieee80211_get_tx_rates(struct ieee80211_vif *vif, 849 struct ieee80211_sta *sta, 850 struct sk_buff *skb, 851 struct ieee80211_tx_rate *dest, 852 int max_rates) 853 { 854 struct ieee80211_sub_if_data *sdata; 855 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 856 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 857 struct ieee80211_supported_band *sband; 858 859 rate_control_fill_sta_table(sta, info, dest, max_rates); 860 861 if (!vif) 862 return; 863 864 sdata = vif_to_sdata(vif); 865 sband = sdata->local->hw.wiphy->bands[info->band]; 866 867 if (ieee80211_is_data(hdr->frame_control)) 868 rate_control_apply_mask(sdata, sta, sband, dest, max_rates); 869 870 if (dest[0].idx < 0) 871 __rate_control_send_low(&sdata->local->hw, sband, sta, info, 872 sdata->rc_rateidx_mask[info->band]); 873 874 if (sta) 875 rate_fixup_ratelist(vif, sband, info, dest, max_rates); 876 } 877 EXPORT_SYMBOL(ieee80211_get_tx_rates); 878 879 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, 880 struct sta_info *sta, 881 struct ieee80211_tx_rate_control *txrc) 882 { 883 struct rate_control_ref *ref = sdata->local->rate_ctrl; 884 void *priv_sta = NULL; 885 struct ieee80211_sta *ista = NULL; 886 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 887 int i; 888 889 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) { 890 ista = &sta->sta; 891 priv_sta = sta->rate_ctrl_priv; 892 } 893 894 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 895 info->control.rates[i].idx = -1; 896 info->control.rates[i].flags = 0; 897 info->control.rates[i].count = 0; 898 } 899 900 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL)) 901 return; 902 903 if (rate_control_send_low(ista, txrc)) 904 return; 905 906 if (ista) { 907 spin_lock_bh(&sta->rate_ctrl_lock); 908 ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); 909 spin_unlock_bh(&sta->rate_ctrl_lock); 910 } else { 911 rate_control_send_low(NULL, txrc); 912 } 913 914 if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE)) 915 return; 916 917 ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb, 918 info->control.rates, 919 ARRAY_SIZE(info->control.rates)); 920 } 921 922 int rate_control_set_rates(struct ieee80211_hw *hw, 923 struct ieee80211_sta *pubsta, 924 struct ieee80211_sta_rates *rates) 925 { 926 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 927 struct ieee80211_sta_rates *old; 928 struct ieee80211_supported_band *sband; 929 930 sband = ieee80211_get_sband(sta->sdata); 931 if (!sband) 932 return -EINVAL; 933 rate_control_apply_mask_ratetbl(sta, sband, rates); 934 /* 935 * mac80211 guarantees that this function will not be called 936 * concurrently, so the following RCU access is safe, even without 937 * extra locking. This can not be checked easily, so we just set 938 * the condition to true. 939 */ 940 old = rcu_dereference_protected(pubsta->rates, true); 941 rcu_assign_pointer(pubsta->rates, rates); 942 if (old) 943 kfree_rcu(old, rcu_head); 944 945 drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta); 946 947 ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta)); 948 949 return 0; 950 } 951 EXPORT_SYMBOL(rate_control_set_rates); 952 953 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, 954 const char *name) 955 { 956 struct rate_control_ref *ref; 957 958 ASSERT_RTNL(); 959 960 if (local->open_count) 961 return -EBUSY; 962 963 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) { 964 if (WARN_ON(!local->ops->set_rts_threshold)) 965 return -EINVAL; 966 return 0; 967 } 968 969 ref = rate_control_alloc(name, local); 970 if (!ref) { 971 wiphy_warn(local->hw.wiphy, 972 "Failed to select rate control algorithm\n"); 973 return -ENOENT; 974 } 975 976 WARN_ON(local->rate_ctrl); 977 local->rate_ctrl = ref; 978 979 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", 980 ref->ops->name); 981 982 return 0; 983 } 984 985 void rate_control_deinitialize(struct ieee80211_local *local) 986 { 987 struct rate_control_ref *ref; 988 989 ref = local->rate_ctrl; 990 991 if (!ref) 992 return; 993 994 local->rate_ctrl = NULL; 995 rate_control_free(local, ref); 996 } 997