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 bool rate_control_send_low(struct ieee80211_sta *pubsta, 373 void *priv_sta, 374 struct ieee80211_tx_rate_control *txrc) 375 { 376 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 377 struct ieee80211_supported_band *sband = txrc->sband; 378 struct sta_info *sta; 379 int mcast_rate; 380 bool use_basicrate = false; 381 382 if (!pubsta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) { 383 __rate_control_send_low(txrc->hw, sband, pubsta, info, 384 txrc->rate_idx_mask); 385 386 if (!pubsta && txrc->bss) { 387 mcast_rate = txrc->bss_conf->mcast_rate[sband->band]; 388 if (mcast_rate > 0) { 389 info->control.rates[0].idx = mcast_rate - 1; 390 return true; 391 } 392 use_basicrate = true; 393 } else if (pubsta) { 394 sta = container_of(pubsta, struct sta_info, sta); 395 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) 396 use_basicrate = true; 397 } 398 399 if (use_basicrate) 400 rc_send_low_basicrate(&info->control.rates[0].idx, 401 txrc->bss_conf->basic_rates, 402 sband); 403 404 return true; 405 } 406 return false; 407 } 408 EXPORT_SYMBOL(rate_control_send_low); 409 410 static bool rate_idx_match_legacy_mask(s8 *rate_idx, int n_bitrates, u32 mask) 411 { 412 int j; 413 414 /* See whether the selected rate or anything below it is allowed. */ 415 for (j = *rate_idx; j >= 0; j--) { 416 if (mask & (1 << j)) { 417 /* Okay, found a suitable rate. Use it. */ 418 *rate_idx = j; 419 return true; 420 } 421 } 422 423 /* Try to find a higher rate that would be allowed */ 424 for (j = *rate_idx + 1; j < n_bitrates; j++) { 425 if (mask & (1 << j)) { 426 /* Okay, found a suitable rate. Use it. */ 427 *rate_idx = j; 428 return true; 429 } 430 } 431 return false; 432 } 433 434 static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask) 435 { 436 int i, j; 437 int ridx, rbit; 438 439 ridx = *rate_idx / 8; 440 rbit = *rate_idx % 8; 441 442 /* sanity check */ 443 if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN) 444 return false; 445 446 /* See whether the selected rate or anything below it is allowed. */ 447 for (i = ridx; i >= 0; i--) { 448 for (j = rbit; j >= 0; j--) 449 if (mcs_mask[i] & BIT(j)) { 450 *rate_idx = i * 8 + j; 451 return true; 452 } 453 rbit = 7; 454 } 455 456 /* Try to find a higher rate that would be allowed */ 457 ridx = (*rate_idx + 1) / 8; 458 rbit = (*rate_idx + 1) % 8; 459 460 for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) { 461 for (j = rbit; j < 8; j++) 462 if (mcs_mask[i] & BIT(j)) { 463 *rate_idx = i * 8 + j; 464 return true; 465 } 466 rbit = 0; 467 } 468 return false; 469 } 470 471 static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask) 472 { 473 int i, j; 474 int ridx, rbit; 475 476 ridx = *rate_idx >> 4; 477 rbit = *rate_idx & 0xf; 478 479 if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX) 480 return false; 481 482 /* See whether the selected rate or anything below it is allowed. */ 483 for (i = ridx; i >= 0; i--) { 484 for (j = rbit; j >= 0; j--) { 485 if (vht_mask[i] & BIT(j)) { 486 *rate_idx = (i << 4) | j; 487 return true; 488 } 489 } 490 rbit = 15; 491 } 492 493 /* Try to find a higher rate that would be allowed */ 494 ridx = (*rate_idx + 1) >> 4; 495 rbit = (*rate_idx + 1) & 0xf; 496 497 for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) { 498 for (j = rbit; j < 16; j++) { 499 if (vht_mask[i] & BIT(j)) { 500 *rate_idx = (i << 4) | j; 501 return true; 502 } 503 } 504 rbit = 0; 505 } 506 return false; 507 } 508 509 static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags, 510 struct ieee80211_supported_band *sband, 511 enum nl80211_chan_width chan_width, 512 u32 mask, 513 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 514 u16 vht_mask[NL80211_VHT_NSS_MAX]) 515 { 516 if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) { 517 /* handle VHT rates */ 518 if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask)) 519 return; 520 521 *rate_idx = 0; 522 /* keep protection flags */ 523 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 524 IEEE80211_TX_RC_USE_CTS_PROTECT | 525 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 526 527 *rate_flags |= IEEE80211_TX_RC_MCS; 528 if (chan_width == NL80211_CHAN_WIDTH_40) 529 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 530 531 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 532 return; 533 534 /* also try the legacy rates. */ 535 *rate_flags &= ~(IEEE80211_TX_RC_MCS | 536 IEEE80211_TX_RC_40_MHZ_WIDTH); 537 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 538 mask)) 539 return; 540 } else if (*rate_flags & IEEE80211_TX_RC_MCS) { 541 /* handle HT rates */ 542 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 543 return; 544 545 /* also try the legacy rates. */ 546 *rate_idx = 0; 547 /* keep protection flags */ 548 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 549 IEEE80211_TX_RC_USE_CTS_PROTECT | 550 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 551 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 552 mask)) 553 return; 554 } else { 555 /* handle legacy rates */ 556 if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates, 557 mask)) 558 return; 559 560 /* if HT BSS, and we handle a data frame, also try HT rates */ 561 switch (chan_width) { 562 case NL80211_CHAN_WIDTH_20_NOHT: 563 case NL80211_CHAN_WIDTH_5: 564 case NL80211_CHAN_WIDTH_10: 565 return; 566 default: 567 break; 568 } 569 570 *rate_idx = 0; 571 /* keep protection flags */ 572 *rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS | 573 IEEE80211_TX_RC_USE_CTS_PROTECT | 574 IEEE80211_TX_RC_USE_SHORT_PREAMBLE); 575 576 *rate_flags |= IEEE80211_TX_RC_MCS; 577 578 if (chan_width == NL80211_CHAN_WIDTH_40) 579 *rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH; 580 581 if (rate_idx_match_mcs_mask(rate_idx, mcs_mask)) 582 return; 583 } 584 585 /* 586 * Uh.. No suitable rate exists. This should not really happen with 587 * sane TX rate mask configurations. However, should someone manage to 588 * configure supported rates and TX rate mask in incompatible way, 589 * allow the frame to be transmitted with whatever the rate control 590 * selected. 591 */ 592 } 593 594 static void rate_fixup_ratelist(struct ieee80211_vif *vif, 595 struct ieee80211_supported_band *sband, 596 struct ieee80211_tx_info *info, 597 struct ieee80211_tx_rate *rates, 598 int max_rates) 599 { 600 struct ieee80211_rate *rate; 601 bool inval = false; 602 int i; 603 604 /* 605 * Set up the RTS/CTS rate as the fastest basic rate 606 * that is not faster than the data rate unless there 607 * is no basic rate slower than the data rate, in which 608 * case we pick the slowest basic rate 609 * 610 * XXX: Should this check all retry rates? 611 */ 612 if (!(rates[0].flags & 613 (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) { 614 u32 basic_rates = vif->bss_conf.basic_rates; 615 s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0; 616 617 rate = &sband->bitrates[rates[0].idx]; 618 619 for (i = 0; i < sband->n_bitrates; i++) { 620 /* must be a basic rate */ 621 if (!(basic_rates & BIT(i))) 622 continue; 623 /* must not be faster than the data rate */ 624 if (sband->bitrates[i].bitrate > rate->bitrate) 625 continue; 626 /* maximum */ 627 if (sband->bitrates[baserate].bitrate < 628 sband->bitrates[i].bitrate) 629 baserate = i; 630 } 631 632 info->control.rts_cts_rate_idx = baserate; 633 } 634 635 for (i = 0; i < max_rates; i++) { 636 /* 637 * make sure there's no valid rate following 638 * an invalid one, just in case drivers don't 639 * take the API seriously to stop at -1. 640 */ 641 if (inval) { 642 rates[i].idx = -1; 643 continue; 644 } 645 if (rates[i].idx < 0) { 646 inval = true; 647 continue; 648 } 649 650 /* 651 * For now assume MCS is already set up correctly, this 652 * needs to be fixed. 653 */ 654 if (rates[i].flags & IEEE80211_TX_RC_MCS) { 655 WARN_ON(rates[i].idx > 76); 656 657 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 658 info->control.use_cts_prot) 659 rates[i].flags |= 660 IEEE80211_TX_RC_USE_CTS_PROTECT; 661 continue; 662 } 663 664 if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) { 665 WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9); 666 continue; 667 } 668 669 /* set up RTS protection if desired */ 670 if (info->control.use_rts) { 671 rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS; 672 info->control.use_cts_prot = false; 673 } 674 675 /* RC is busted */ 676 if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) { 677 rates[i].idx = -1; 678 continue; 679 } 680 681 rate = &sband->bitrates[rates[i].idx]; 682 683 /* set up short preamble */ 684 if (info->control.short_preamble && 685 rate->flags & IEEE80211_RATE_SHORT_PREAMBLE) 686 rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE; 687 688 /* set up G protection */ 689 if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) && 690 info->control.use_cts_prot && 691 rate->flags & IEEE80211_RATE_ERP_G) 692 rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT; 693 } 694 } 695 696 697 static void rate_control_fill_sta_table(struct ieee80211_sta *sta, 698 struct ieee80211_tx_info *info, 699 struct ieee80211_tx_rate *rates, 700 int max_rates) 701 { 702 struct ieee80211_sta_rates *ratetbl = NULL; 703 int i; 704 705 if (sta && !info->control.skip_table) 706 ratetbl = rcu_dereference(sta->rates); 707 708 /* Fill remaining rate slots with data from the sta rate table. */ 709 max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE); 710 for (i = 0; i < max_rates; i++) { 711 if (i < ARRAY_SIZE(info->control.rates) && 712 info->control.rates[i].idx >= 0 && 713 info->control.rates[i].count) { 714 if (rates != info->control.rates) 715 rates[i] = info->control.rates[i]; 716 } else if (ratetbl) { 717 rates[i].idx = ratetbl->rate[i].idx; 718 rates[i].flags = ratetbl->rate[i].flags; 719 if (info->control.use_rts) 720 rates[i].count = ratetbl->rate[i].count_rts; 721 else if (info->control.use_cts_prot) 722 rates[i].count = ratetbl->rate[i].count_cts; 723 else 724 rates[i].count = ratetbl->rate[i].count; 725 } else { 726 rates[i].idx = -1; 727 rates[i].count = 0; 728 } 729 730 if (rates[i].idx < 0 || !rates[i].count) 731 break; 732 } 733 } 734 735 static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata, 736 struct ieee80211_supported_band *sband, 737 struct ieee80211_sta *sta, u32 *mask, 738 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN], 739 u16 vht_mask[NL80211_VHT_NSS_MAX]) 740 { 741 u32 i, flags; 742 743 *mask = sdata->rc_rateidx_mask[sband->band]; 744 flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef); 745 for (i = 0; i < sband->n_bitrates; i++) { 746 if ((flags & sband->bitrates[i].flags) != flags) 747 *mask &= ~BIT(i); 748 } 749 750 if (*mask == (1 << sband->n_bitrates) - 1 && 751 !sdata->rc_has_mcs_mask[sband->band] && 752 !sdata->rc_has_vht_mcs_mask[sband->band]) 753 return false; 754 755 if (sdata->rc_has_mcs_mask[sband->band]) 756 memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band], 757 IEEE80211_HT_MCS_MASK_LEN); 758 else 759 memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN); 760 761 if (sdata->rc_has_vht_mcs_mask[sband->band]) 762 memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band], 763 sizeof(u16) * NL80211_VHT_NSS_MAX); 764 else 765 memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX); 766 767 if (sta) { 768 __le16 sta_vht_cap; 769 u16 sta_vht_mask[NL80211_VHT_NSS_MAX]; 770 771 /* Filter out rates that the STA does not support */ 772 *mask &= sta->supp_rates[sband->band]; 773 for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++) 774 mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i]; 775 776 sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map; 777 ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask); 778 for (i = 0; i < NL80211_VHT_NSS_MAX; i++) 779 vht_mask[i] &= sta_vht_mask[i]; 780 } 781 782 return true; 783 } 784 785 static void 786 rate_control_apply_mask_ratetbl(struct sta_info *sta, 787 struct ieee80211_supported_band *sband, 788 struct ieee80211_sta_rates *rates) 789 { 790 int i; 791 u32 mask; 792 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 793 u16 vht_mask[NL80211_VHT_NSS_MAX]; 794 enum nl80211_chan_width chan_width; 795 796 if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask, 797 mcs_mask, vht_mask)) 798 return; 799 800 chan_width = sta->sdata->vif.bss_conf.chandef.width; 801 for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) { 802 if (rates->rate[i].idx < 0) 803 break; 804 805 rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags, 806 sband, chan_width, mask, mcs_mask, 807 vht_mask); 808 } 809 } 810 811 static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata, 812 struct ieee80211_sta *sta, 813 struct ieee80211_supported_band *sband, 814 struct ieee80211_tx_rate *rates, 815 int max_rates) 816 { 817 enum nl80211_chan_width chan_width; 818 u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN]; 819 u32 mask; 820 u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX]; 821 int i; 822 823 /* 824 * Try to enforce the rateidx mask the user wanted. skip this if the 825 * default mask (allow all rates) is used to save some processing for 826 * the common case. 827 */ 828 if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask, 829 vht_mask)) 830 return; 831 832 /* 833 * Make sure the rate index selected for each TX rate is 834 * included in the configured mask and change the rate indexes 835 * if needed. 836 */ 837 chan_width = sdata->vif.bss_conf.chandef.width; 838 for (i = 0; i < max_rates; i++) { 839 /* Skip invalid rates */ 840 if (rates[i].idx < 0) 841 break; 842 843 rate_flags = rates[i].flags; 844 rate_idx_match_mask(&rates[i].idx, &rate_flags, sband, 845 chan_width, mask, mcs_mask, vht_mask); 846 rates[i].flags = rate_flags; 847 } 848 } 849 850 void ieee80211_get_tx_rates(struct ieee80211_vif *vif, 851 struct ieee80211_sta *sta, 852 struct sk_buff *skb, 853 struct ieee80211_tx_rate *dest, 854 int max_rates) 855 { 856 struct ieee80211_sub_if_data *sdata; 857 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 858 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 859 struct ieee80211_supported_band *sband; 860 861 rate_control_fill_sta_table(sta, info, dest, max_rates); 862 863 if (!vif) 864 return; 865 866 sdata = vif_to_sdata(vif); 867 sband = sdata->local->hw.wiphy->bands[info->band]; 868 869 if (ieee80211_is_data(hdr->frame_control)) 870 rate_control_apply_mask(sdata, sta, sband, dest, max_rates); 871 872 if (dest[0].idx < 0) 873 __rate_control_send_low(&sdata->local->hw, sband, sta, info, 874 sdata->rc_rateidx_mask[info->band]); 875 876 if (sta) 877 rate_fixup_ratelist(vif, sband, info, dest, max_rates); 878 } 879 EXPORT_SYMBOL(ieee80211_get_tx_rates); 880 881 void rate_control_get_rate(struct ieee80211_sub_if_data *sdata, 882 struct sta_info *sta, 883 struct ieee80211_tx_rate_control *txrc) 884 { 885 struct rate_control_ref *ref = sdata->local->rate_ctrl; 886 void *priv_sta = NULL; 887 struct ieee80211_sta *ista = NULL; 888 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 889 int i; 890 891 if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) { 892 ista = &sta->sta; 893 priv_sta = sta->rate_ctrl_priv; 894 } 895 896 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { 897 info->control.rates[i].idx = -1; 898 info->control.rates[i].flags = 0; 899 info->control.rates[i].count = 0; 900 } 901 902 if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL)) 903 return; 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 ref->ops->get_rate(ref->priv, NULL, 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 return 0; 947 } 948 EXPORT_SYMBOL(rate_control_set_rates); 949 950 int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local, 951 const char *name) 952 { 953 struct rate_control_ref *ref; 954 955 ASSERT_RTNL(); 956 957 if (local->open_count) 958 return -EBUSY; 959 960 if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) { 961 if (WARN_ON(!local->ops->set_rts_threshold)) 962 return -EINVAL; 963 return 0; 964 } 965 966 ref = rate_control_alloc(name, local); 967 if (!ref) { 968 wiphy_warn(local->hw.wiphy, 969 "Failed to select rate control algorithm\n"); 970 return -ENOENT; 971 } 972 973 WARN_ON(local->rate_ctrl); 974 local->rate_ctrl = ref; 975 976 wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n", 977 ref->ops->name); 978 979 return 0; 980 } 981 982 void rate_control_deinitialize(struct ieee80211_local *local) 983 { 984 struct rate_control_ref *ref; 985 986 ref = local->rate_ctrl; 987 988 if (!ref) 989 return; 990 991 local->rate_ctrl = NULL; 992 rate_control_free(local, ref); 993 } 994 995