1 /* 2 * Copyright 2002-2005, Instant802 Networks, Inc. 3 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/netdevice.h> 13 #include <linux/types.h> 14 #include <linux/slab.h> 15 #include <linux/skbuff.h> 16 #include <linux/if_arp.h> 17 #include <linux/timer.h> 18 #include <linux/rtnetlink.h> 19 20 #include <net/mac80211.h> 21 #include "ieee80211_i.h" 22 #include "driver-ops.h" 23 #include "rate.h" 24 #include "sta_info.h" 25 #include "debugfs_sta.h" 26 #include "mesh.h" 27 28 /** 29 * DOC: STA information lifetime rules 30 * 31 * STA info structures (&struct sta_info) are managed in a hash table 32 * for faster lookup and a list for iteration. They are managed using 33 * RCU, i.e. access to the list and hash table is protected by RCU. 34 * 35 * Upon allocating a STA info structure with sta_info_alloc(), the caller 36 * owns that structure. It must then insert it into the hash table using 37 * either sta_info_insert() or sta_info_insert_rcu(); only in the latter 38 * case (which acquires an rcu read section but must not be called from 39 * within one) will the pointer still be valid after the call. Note that 40 * the caller may not do much with the STA info before inserting it, in 41 * particular, it may not start any mesh peer link management or add 42 * encryption keys. 43 * 44 * When the insertion fails (sta_info_insert()) returns non-zero), the 45 * structure will have been freed by sta_info_insert()! 46 * 47 * Station entries are added by mac80211 when you establish a link with a 48 * peer. This means different things for the different type of interfaces 49 * we support. For a regular station this mean we add the AP sta when we 50 * receive an association response from the AP. For IBSS this occurs when 51 * get to know about a peer on the same IBSS. For WDS we add the sta for 52 * the peer immediately upon device open. When using AP mode we add stations 53 * for each respective station upon request from userspace through nl80211. 54 * 55 * In order to remove a STA info structure, various sta_info_destroy_*() 56 * calls are available. 57 * 58 * There is no concept of ownership on a STA entry, each structure is 59 * owned by the global hash table/list until it is removed. All users of 60 * the structure need to be RCU protected so that the structure won't be 61 * freed before they are done using it. 62 */ 63 64 /* Caller must hold local->sta_lock */ 65 static int sta_info_hash_del(struct ieee80211_local *local, 66 struct sta_info *sta) 67 { 68 struct sta_info *s; 69 70 s = rcu_dereference_protected(local->sta_hash[STA_HASH(sta->sta.addr)], 71 lockdep_is_held(&local->sta_lock)); 72 if (!s) 73 return -ENOENT; 74 if (s == sta) { 75 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], 76 s->hnext); 77 return 0; 78 } 79 80 while (rcu_access_pointer(s->hnext) && 81 rcu_access_pointer(s->hnext) != sta) 82 s = rcu_dereference_protected(s->hnext, 83 lockdep_is_held(&local->sta_lock)); 84 if (rcu_access_pointer(s->hnext)) { 85 rcu_assign_pointer(s->hnext, sta->hnext); 86 return 0; 87 } 88 89 return -ENOENT; 90 } 91 92 /* protected by RCU */ 93 struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata, 94 const u8 *addr) 95 { 96 struct ieee80211_local *local = sdata->local; 97 struct sta_info *sta; 98 99 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], 100 lockdep_is_held(&local->sta_lock) || 101 lockdep_is_held(&local->sta_mtx)); 102 while (sta) { 103 if (sta->sdata == sdata && !sta->dummy && 104 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 105 break; 106 sta = rcu_dereference_check(sta->hnext, 107 lockdep_is_held(&local->sta_lock) || 108 lockdep_is_held(&local->sta_mtx)); 109 } 110 return sta; 111 } 112 113 /* get a station info entry even if it is a dummy station*/ 114 struct sta_info *sta_info_get_rx(struct ieee80211_sub_if_data *sdata, 115 const u8 *addr) 116 { 117 struct ieee80211_local *local = sdata->local; 118 struct sta_info *sta; 119 120 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], 121 lockdep_is_held(&local->sta_lock) || 122 lockdep_is_held(&local->sta_mtx)); 123 while (sta) { 124 if (sta->sdata == sdata && 125 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 126 break; 127 sta = rcu_dereference_check(sta->hnext, 128 lockdep_is_held(&local->sta_lock) || 129 lockdep_is_held(&local->sta_mtx)); 130 } 131 return sta; 132 } 133 134 /* 135 * Get sta info either from the specified interface 136 * or from one of its vlans 137 */ 138 struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata, 139 const u8 *addr) 140 { 141 struct ieee80211_local *local = sdata->local; 142 struct sta_info *sta; 143 144 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], 145 lockdep_is_held(&local->sta_lock) || 146 lockdep_is_held(&local->sta_mtx)); 147 while (sta) { 148 if ((sta->sdata == sdata || 149 (sta->sdata->bss && sta->sdata->bss == sdata->bss)) && 150 !sta->dummy && 151 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 152 break; 153 sta = rcu_dereference_check(sta->hnext, 154 lockdep_is_held(&local->sta_lock) || 155 lockdep_is_held(&local->sta_mtx)); 156 } 157 return sta; 158 } 159 160 /* 161 * Get sta info either from the specified interface 162 * or from one of its vlans (including dummy stations) 163 */ 164 struct sta_info *sta_info_get_bss_rx(struct ieee80211_sub_if_data *sdata, 165 const u8 *addr) 166 { 167 struct ieee80211_local *local = sdata->local; 168 struct sta_info *sta; 169 170 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], 171 lockdep_is_held(&local->sta_lock) || 172 lockdep_is_held(&local->sta_mtx)); 173 while (sta) { 174 if ((sta->sdata == sdata || 175 (sta->sdata->bss && sta->sdata->bss == sdata->bss)) && 176 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 177 break; 178 sta = rcu_dereference_check(sta->hnext, 179 lockdep_is_held(&local->sta_lock) || 180 lockdep_is_held(&local->sta_mtx)); 181 } 182 return sta; 183 } 184 185 struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata, 186 int idx) 187 { 188 struct ieee80211_local *local = sdata->local; 189 struct sta_info *sta; 190 int i = 0; 191 192 list_for_each_entry_rcu(sta, &local->sta_list, list) { 193 if (sdata != sta->sdata) 194 continue; 195 if (i < idx) { 196 ++i; 197 continue; 198 } 199 return sta; 200 } 201 202 return NULL; 203 } 204 205 /** 206 * __sta_info_free - internal STA free helper 207 * 208 * @local: pointer to the global information 209 * @sta: STA info to free 210 * 211 * This function must undo everything done by sta_info_alloc() 212 * that may happen before sta_info_insert(). 213 */ 214 static void __sta_info_free(struct ieee80211_local *local, 215 struct sta_info *sta) 216 { 217 if (sta->rate_ctrl) { 218 rate_control_free_sta(sta); 219 rate_control_put(sta->rate_ctrl); 220 } 221 222 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 223 wiphy_debug(local->hw.wiphy, "Destroyed STA %pM\n", sta->sta.addr); 224 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 225 226 kfree(sta); 227 } 228 229 /* Caller must hold local->sta_lock */ 230 static void sta_info_hash_add(struct ieee80211_local *local, 231 struct sta_info *sta) 232 { 233 sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)]; 234 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta); 235 } 236 237 static void sta_unblock(struct work_struct *wk) 238 { 239 struct sta_info *sta; 240 241 sta = container_of(wk, struct sta_info, drv_unblock_wk); 242 243 if (sta->dead) 244 return; 245 246 if (!test_sta_flags(sta, WLAN_STA_PS_STA)) 247 ieee80211_sta_ps_deliver_wakeup(sta); 248 else if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL)) { 249 clear_sta_flags(sta, WLAN_STA_PS_DRIVER); 250 ieee80211_sta_ps_deliver_poll_response(sta); 251 } else 252 clear_sta_flags(sta, WLAN_STA_PS_DRIVER); 253 } 254 255 static int sta_prepare_rate_control(struct ieee80211_local *local, 256 struct sta_info *sta, gfp_t gfp) 257 { 258 if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) 259 return 0; 260 261 sta->rate_ctrl = rate_control_get(local->rate_ctrl); 262 sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, 263 &sta->sta, gfp); 264 if (!sta->rate_ctrl_priv) { 265 rate_control_put(sta->rate_ctrl); 266 return -ENOMEM; 267 } 268 269 return 0; 270 } 271 272 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, 273 u8 *addr, gfp_t gfp) 274 { 275 struct ieee80211_local *local = sdata->local; 276 struct sta_info *sta; 277 struct timespec uptime; 278 int i; 279 280 sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); 281 if (!sta) 282 return NULL; 283 284 spin_lock_init(&sta->lock); 285 spin_lock_init(&sta->flaglock); 286 INIT_WORK(&sta->drv_unblock_wk, sta_unblock); 287 INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work); 288 mutex_init(&sta->ampdu_mlme.mtx); 289 290 memcpy(sta->sta.addr, addr, ETH_ALEN); 291 sta->local = local; 292 sta->sdata = sdata; 293 sta->last_rx = jiffies; 294 295 do_posix_clock_monotonic_gettime(&uptime); 296 sta->last_connected = uptime.tv_sec; 297 ewma_init(&sta->avg_signal, 1024, 8); 298 299 if (sta_prepare_rate_control(local, sta, gfp)) { 300 kfree(sta); 301 return NULL; 302 } 303 304 for (i = 0; i < STA_TID_NUM; i++) { 305 /* 306 * timer_to_tid must be initialized with identity mapping 307 * to enable session_timer's data differentiation. See 308 * sta_rx_agg_session_timer_expired for usage. 309 */ 310 sta->timer_to_tid[i] = i; 311 } 312 for (i = 0; i < IEEE80211_NUM_ACS; i++) { 313 skb_queue_head_init(&sta->ps_tx_buf[i]); 314 skb_queue_head_init(&sta->tx_filtered[i]); 315 } 316 317 for (i = 0; i < NUM_RX_DATA_QUEUES; i++) 318 sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX); 319 320 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 321 wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr); 322 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 323 324 #ifdef CONFIG_MAC80211_MESH 325 sta->plink_state = NL80211_PLINK_LISTEN; 326 init_timer(&sta->plink_timer); 327 #endif 328 329 return sta; 330 } 331 332 static int sta_info_finish_insert(struct sta_info *sta, 333 bool async, bool dummy_reinsert) 334 { 335 struct ieee80211_local *local = sta->local; 336 struct ieee80211_sub_if_data *sdata = sta->sdata; 337 struct station_info sinfo; 338 unsigned long flags; 339 int err = 0; 340 341 lockdep_assert_held(&local->sta_mtx); 342 343 if (!sta->dummy || dummy_reinsert) { 344 /* notify driver */ 345 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 346 sdata = container_of(sdata->bss, 347 struct ieee80211_sub_if_data, 348 u.ap); 349 err = drv_sta_add(local, sdata, &sta->sta); 350 if (err) { 351 if (!async) 352 return err; 353 printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to " 354 "driver (%d) - keeping it anyway.\n", 355 sdata->name, sta->sta.addr, err); 356 } else { 357 sta->uploaded = true; 358 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 359 if (async) 360 wiphy_debug(local->hw.wiphy, 361 "Finished adding IBSS STA %pM\n", 362 sta->sta.addr); 363 #endif 364 } 365 366 sdata = sta->sdata; 367 } 368 369 if (!dummy_reinsert) { 370 if (!async) { 371 local->num_sta++; 372 local->sta_generation++; 373 smp_mb(); 374 375 /* make the station visible */ 376 spin_lock_irqsave(&local->sta_lock, flags); 377 sta_info_hash_add(local, sta); 378 spin_unlock_irqrestore(&local->sta_lock, flags); 379 } 380 381 list_add(&sta->list, &local->sta_list); 382 } else { 383 sta->dummy = false; 384 } 385 386 if (!sta->dummy) { 387 ieee80211_sta_debugfs_add(sta); 388 rate_control_add_sta_debugfs(sta); 389 390 memset(&sinfo, 0, sizeof(sinfo)); 391 sinfo.filled = 0; 392 sinfo.generation = local->sta_generation; 393 cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL); 394 } 395 396 return 0; 397 } 398 399 static void sta_info_finish_pending(struct ieee80211_local *local) 400 { 401 struct sta_info *sta; 402 unsigned long flags; 403 404 spin_lock_irqsave(&local->sta_lock, flags); 405 while (!list_empty(&local->sta_pending_list)) { 406 sta = list_first_entry(&local->sta_pending_list, 407 struct sta_info, list); 408 list_del(&sta->list); 409 spin_unlock_irqrestore(&local->sta_lock, flags); 410 411 sta_info_finish_insert(sta, true, false); 412 413 spin_lock_irqsave(&local->sta_lock, flags); 414 } 415 spin_unlock_irqrestore(&local->sta_lock, flags); 416 } 417 418 static void sta_info_finish_work(struct work_struct *work) 419 { 420 struct ieee80211_local *local = 421 container_of(work, struct ieee80211_local, sta_finish_work); 422 423 mutex_lock(&local->sta_mtx); 424 sta_info_finish_pending(local); 425 mutex_unlock(&local->sta_mtx); 426 } 427 428 static int sta_info_insert_check(struct sta_info *sta) 429 { 430 struct ieee80211_sub_if_data *sdata = sta->sdata; 431 432 /* 433 * Can't be a WARN_ON because it can be triggered through a race: 434 * something inserts a STA (on one CPU) without holding the RTNL 435 * and another CPU turns off the net device. 436 */ 437 if (unlikely(!ieee80211_sdata_running(sdata))) 438 return -ENETDOWN; 439 440 if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 || 441 is_multicast_ether_addr(sta->sta.addr))) 442 return -EINVAL; 443 444 return 0; 445 } 446 447 static int sta_info_insert_ibss(struct sta_info *sta) __acquires(RCU) 448 { 449 struct ieee80211_local *local = sta->local; 450 struct ieee80211_sub_if_data *sdata = sta->sdata; 451 unsigned long flags; 452 453 spin_lock_irqsave(&local->sta_lock, flags); 454 /* check if STA exists already */ 455 if (sta_info_get_bss_rx(sdata, sta->sta.addr)) { 456 spin_unlock_irqrestore(&local->sta_lock, flags); 457 rcu_read_lock(); 458 return -EEXIST; 459 } 460 461 local->num_sta++; 462 local->sta_generation++; 463 smp_mb(); 464 sta_info_hash_add(local, sta); 465 466 list_add_tail(&sta->list, &local->sta_pending_list); 467 468 rcu_read_lock(); 469 spin_unlock_irqrestore(&local->sta_lock, flags); 470 471 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 472 wiphy_debug(local->hw.wiphy, "Added IBSS STA %pM\n", 473 sta->sta.addr); 474 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 475 476 ieee80211_queue_work(&local->hw, &local->sta_finish_work); 477 478 return 0; 479 } 480 481 /* 482 * should be called with sta_mtx locked 483 * this function replaces the mutex lock 484 * with a RCU lock 485 */ 486 static int sta_info_insert_non_ibss(struct sta_info *sta) __acquires(RCU) 487 { 488 struct ieee80211_local *local = sta->local; 489 struct ieee80211_sub_if_data *sdata = sta->sdata; 490 unsigned long flags; 491 struct sta_info *exist_sta; 492 bool dummy_reinsert = false; 493 int err = 0; 494 495 lockdep_assert_held(&local->sta_mtx); 496 497 /* 498 * On first glance, this will look racy, because the code 499 * in this function, which inserts a station with sleeping, 500 * unlocks the sta_lock between checking existence in the 501 * hash table and inserting into it. 502 * 503 * However, it is not racy against itself because it keeps 504 * the mutex locked. 505 */ 506 507 spin_lock_irqsave(&local->sta_lock, flags); 508 /* 509 * check if STA exists already. 510 * only accept a scenario of a second call to sta_info_insert_non_ibss 511 * with a dummy station entry that was inserted earlier 512 * in that case - assume that the dummy station flag should 513 * be removed. 514 */ 515 exist_sta = sta_info_get_bss_rx(sdata, sta->sta.addr); 516 if (exist_sta) { 517 if (exist_sta == sta && sta->dummy) { 518 dummy_reinsert = true; 519 } else { 520 spin_unlock_irqrestore(&local->sta_lock, flags); 521 mutex_unlock(&local->sta_mtx); 522 rcu_read_lock(); 523 return -EEXIST; 524 } 525 } 526 527 spin_unlock_irqrestore(&local->sta_lock, flags); 528 529 err = sta_info_finish_insert(sta, false, dummy_reinsert); 530 if (err) { 531 mutex_unlock(&local->sta_mtx); 532 rcu_read_lock(); 533 return err; 534 } 535 536 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 537 wiphy_debug(local->hw.wiphy, "Inserted %sSTA %pM\n", 538 sta->dummy ? "dummy " : "", sta->sta.addr); 539 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 540 541 /* move reference to rcu-protected */ 542 rcu_read_lock(); 543 mutex_unlock(&local->sta_mtx); 544 545 if (ieee80211_vif_is_mesh(&sdata->vif)) 546 mesh_accept_plinks_update(sdata); 547 548 return 0; 549 } 550 551 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU) 552 { 553 struct ieee80211_local *local = sta->local; 554 struct ieee80211_sub_if_data *sdata = sta->sdata; 555 int err = 0; 556 557 err = sta_info_insert_check(sta); 558 if (err) { 559 rcu_read_lock(); 560 goto out_free; 561 } 562 563 /* 564 * In ad-hoc mode, we sometimes need to insert stations 565 * from tasklet context from the RX path. To avoid races, 566 * always do so in that case -- see the comment below. 567 */ 568 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 569 err = sta_info_insert_ibss(sta); 570 if (err) 571 goto out_free; 572 573 return 0; 574 } 575 576 /* 577 * It might seem that the function called below is in race against 578 * the function call above that atomically inserts the station... That, 579 * however, is not true because the above code can only 580 * be invoked for IBSS interfaces, and the below code will 581 * not be -- and the two do not race against each other as 582 * the hash table also keys off the interface. 583 */ 584 585 might_sleep(); 586 587 mutex_lock(&local->sta_mtx); 588 589 err = sta_info_insert_non_ibss(sta); 590 if (err) 591 goto out_free; 592 593 return 0; 594 out_free: 595 BUG_ON(!err); 596 __sta_info_free(local, sta); 597 return err; 598 } 599 600 int sta_info_insert(struct sta_info *sta) 601 { 602 int err = sta_info_insert_rcu(sta); 603 604 rcu_read_unlock(); 605 606 return err; 607 } 608 609 /* Caller must hold sta->local->sta_mtx */ 610 int sta_info_reinsert(struct sta_info *sta) 611 { 612 struct ieee80211_local *local = sta->local; 613 int err = 0; 614 615 err = sta_info_insert_check(sta); 616 if (err) { 617 mutex_unlock(&local->sta_mtx); 618 return err; 619 } 620 621 might_sleep(); 622 623 err = sta_info_insert_non_ibss(sta); 624 rcu_read_unlock(); 625 return err; 626 } 627 628 static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid) 629 { 630 /* 631 * This format has been mandated by the IEEE specifications, 632 * so this line may not be changed to use the __set_bit() format. 633 */ 634 bss->tim[aid / 8] |= (1 << (aid % 8)); 635 } 636 637 static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid) 638 { 639 /* 640 * This format has been mandated by the IEEE specifications, 641 * so this line may not be changed to use the __clear_bit() format. 642 */ 643 bss->tim[aid / 8] &= ~(1 << (aid % 8)); 644 } 645 646 static unsigned long ieee80211_tids_for_ac(int ac) 647 { 648 /* If we ever support TIDs > 7, this obviously needs to be adjusted */ 649 switch (ac) { 650 case IEEE80211_AC_VO: 651 return BIT(6) | BIT(7); 652 case IEEE80211_AC_VI: 653 return BIT(4) | BIT(5); 654 case IEEE80211_AC_BE: 655 return BIT(0) | BIT(3); 656 case IEEE80211_AC_BK: 657 return BIT(1) | BIT(2); 658 default: 659 WARN_ON(1); 660 return 0; 661 } 662 } 663 664 void sta_info_recalc_tim(struct sta_info *sta) 665 { 666 struct ieee80211_local *local = sta->local; 667 struct ieee80211_if_ap *bss = sta->sdata->bss; 668 unsigned long flags; 669 bool indicate_tim = false; 670 u8 ignore_for_tim = sta->sta.uapsd_queues; 671 int ac; 672 673 if (WARN_ON_ONCE(!sta->sdata->bss)) 674 return; 675 676 /* No need to do anything if the driver does all */ 677 if (local->hw.flags & IEEE80211_HW_AP_LINK_PS) 678 return; 679 680 if (sta->dead) 681 goto done; 682 683 /* 684 * If all ACs are delivery-enabled then we should build 685 * the TIM bit for all ACs anyway; if only some are then 686 * we ignore those and build the TIM bit using only the 687 * non-enabled ones. 688 */ 689 if (ignore_for_tim == BIT(IEEE80211_NUM_ACS) - 1) 690 ignore_for_tim = 0; 691 692 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { 693 unsigned long tids; 694 695 if (ignore_for_tim & BIT(ac)) 696 continue; 697 698 indicate_tim |= !skb_queue_empty(&sta->tx_filtered[ac]) || 699 !skb_queue_empty(&sta->ps_tx_buf[ac]); 700 if (indicate_tim) 701 break; 702 703 tids = ieee80211_tids_for_ac(ac); 704 705 indicate_tim |= 706 sta->driver_buffered_tids & tids; 707 } 708 709 done: 710 spin_lock_irqsave(&local->sta_lock, flags); 711 712 if (indicate_tim) 713 __bss_tim_set(bss, sta->sta.aid); 714 else 715 __bss_tim_clear(bss, sta->sta.aid); 716 717 if (local->ops->set_tim) { 718 local->tim_in_locked_section = true; 719 drv_set_tim(local, &sta->sta, indicate_tim); 720 local->tim_in_locked_section = false; 721 } 722 723 spin_unlock_irqrestore(&local->sta_lock, flags); 724 } 725 726 static bool sta_info_buffer_expired(struct sta_info *sta, struct sk_buff *skb) 727 { 728 struct ieee80211_tx_info *info; 729 int timeout; 730 731 if (!skb) 732 return false; 733 734 info = IEEE80211_SKB_CB(skb); 735 736 /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */ 737 timeout = (sta->listen_interval * 738 sta->sdata->vif.bss_conf.beacon_int * 739 32 / 15625) * HZ; 740 if (timeout < STA_TX_BUFFER_EXPIRE) 741 timeout = STA_TX_BUFFER_EXPIRE; 742 return time_after(jiffies, info->control.jiffies + timeout); 743 } 744 745 746 static bool sta_info_cleanup_expire_buffered_ac(struct ieee80211_local *local, 747 struct sta_info *sta, int ac) 748 { 749 unsigned long flags; 750 struct sk_buff *skb; 751 752 /* 753 * First check for frames that should expire on the filtered 754 * queue. Frames here were rejected by the driver and are on 755 * a separate queue to avoid reordering with normal PS-buffered 756 * frames. They also aren't accounted for right now in the 757 * total_ps_buffered counter. 758 */ 759 for (;;) { 760 spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags); 761 skb = skb_peek(&sta->tx_filtered[ac]); 762 if (sta_info_buffer_expired(sta, skb)) 763 skb = __skb_dequeue(&sta->tx_filtered[ac]); 764 else 765 skb = NULL; 766 spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags); 767 768 /* 769 * Frames are queued in order, so if this one 770 * hasn't expired yet we can stop testing. If 771 * we actually reached the end of the queue we 772 * also need to stop, of course. 773 */ 774 if (!skb) 775 break; 776 dev_kfree_skb(skb); 777 } 778 779 /* 780 * Now also check the normal PS-buffered queue, this will 781 * only find something if the filtered queue was emptied 782 * since the filtered frames are all before the normal PS 783 * buffered frames. 784 */ 785 for (;;) { 786 spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags); 787 skb = skb_peek(&sta->ps_tx_buf[ac]); 788 if (sta_info_buffer_expired(sta, skb)) 789 skb = __skb_dequeue(&sta->ps_tx_buf[ac]); 790 else 791 skb = NULL; 792 spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags); 793 794 /* 795 * frames are queued in order, so if this one 796 * hasn't expired yet (or we reached the end of 797 * the queue) we can stop testing 798 */ 799 if (!skb) 800 break; 801 802 local->total_ps_buffered--; 803 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 804 printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n", 805 sta->sta.addr); 806 #endif 807 dev_kfree_skb(skb); 808 } 809 810 /* 811 * Finally, recalculate the TIM bit for this station -- it might 812 * now be clear because the station was too slow to retrieve its 813 * frames. 814 */ 815 sta_info_recalc_tim(sta); 816 817 /* 818 * Return whether there are any frames still buffered, this is 819 * used to check whether the cleanup timer still needs to run, 820 * if there are no frames we don't need to rearm the timer. 821 */ 822 return !(skb_queue_empty(&sta->ps_tx_buf[ac]) && 823 skb_queue_empty(&sta->tx_filtered[ac])); 824 } 825 826 static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local, 827 struct sta_info *sta) 828 { 829 bool have_buffered = false; 830 int ac; 831 832 /* This is only necessary for stations on BSS interfaces */ 833 if (!sta->sdata->bss) 834 return false; 835 836 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) 837 have_buffered |= 838 sta_info_cleanup_expire_buffered_ac(local, sta, ac); 839 840 return have_buffered; 841 } 842 843 static int __must_check __sta_info_destroy(struct sta_info *sta) 844 { 845 struct ieee80211_local *local; 846 struct ieee80211_sub_if_data *sdata; 847 unsigned long flags; 848 int ret, i, ac; 849 850 might_sleep(); 851 852 if (!sta) 853 return -ENOENT; 854 855 local = sta->local; 856 sdata = sta->sdata; 857 858 /* 859 * Before removing the station from the driver and 860 * rate control, it might still start new aggregation 861 * sessions -- block that to make sure the tear-down 862 * will be sufficient. 863 */ 864 set_sta_flags(sta, WLAN_STA_BLOCK_BA); 865 ieee80211_sta_tear_down_BA_sessions(sta, true); 866 867 spin_lock_irqsave(&local->sta_lock, flags); 868 ret = sta_info_hash_del(local, sta); 869 /* this might still be the pending list ... which is fine */ 870 if (!ret) 871 list_del(&sta->list); 872 spin_unlock_irqrestore(&local->sta_lock, flags); 873 if (ret) 874 return ret; 875 876 mutex_lock(&local->key_mtx); 877 for (i = 0; i < NUM_DEFAULT_KEYS; i++) 878 __ieee80211_key_free(key_mtx_dereference(local, sta->gtk[i])); 879 if (sta->ptk) 880 __ieee80211_key_free(key_mtx_dereference(local, sta->ptk)); 881 mutex_unlock(&local->key_mtx); 882 883 sta->dead = true; 884 885 if (test_and_clear_sta_flags(sta, 886 WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) { 887 BUG_ON(!sdata->bss); 888 889 atomic_dec(&sdata->bss->num_sta_ps); 890 sta_info_recalc_tim(sta); 891 } 892 893 local->num_sta--; 894 local->sta_generation++; 895 896 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 897 rcu_assign_pointer(sdata->u.vlan.sta, NULL); 898 899 if (sta->uploaded) { 900 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 901 sdata = container_of(sdata->bss, 902 struct ieee80211_sub_if_data, 903 u.ap); 904 drv_sta_remove(local, sdata, &sta->sta); 905 sdata = sta->sdata; 906 } 907 908 /* 909 * At this point, after we wait for an RCU grace period, 910 * neither mac80211 nor the driver can reference this 911 * sta struct any more except by still existing timers 912 * associated with this station that we clean up below. 913 */ 914 synchronize_rcu(); 915 916 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { 917 local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]); 918 __skb_queue_purge(&sta->ps_tx_buf[ac]); 919 __skb_queue_purge(&sta->tx_filtered[ac]); 920 } 921 922 #ifdef CONFIG_MAC80211_MESH 923 if (ieee80211_vif_is_mesh(&sdata->vif)) 924 mesh_accept_plinks_update(sdata); 925 #endif 926 927 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 928 wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr); 929 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 930 cancel_work_sync(&sta->drv_unblock_wk); 931 932 cfg80211_del_sta(sdata->dev, sta->sta.addr, GFP_KERNEL); 933 934 rate_control_remove_sta_debugfs(sta); 935 ieee80211_sta_debugfs_remove(sta); 936 937 #ifdef CONFIG_MAC80211_MESH 938 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) { 939 mesh_plink_deactivate(sta); 940 del_timer_sync(&sta->plink_timer); 941 } 942 #endif 943 944 __sta_info_free(local, sta); 945 946 return 0; 947 } 948 949 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr) 950 { 951 struct sta_info *sta; 952 int ret; 953 954 mutex_lock(&sdata->local->sta_mtx); 955 sta = sta_info_get_rx(sdata, addr); 956 ret = __sta_info_destroy(sta); 957 mutex_unlock(&sdata->local->sta_mtx); 958 959 return ret; 960 } 961 962 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata, 963 const u8 *addr) 964 { 965 struct sta_info *sta; 966 int ret; 967 968 mutex_lock(&sdata->local->sta_mtx); 969 sta = sta_info_get_bss_rx(sdata, addr); 970 ret = __sta_info_destroy(sta); 971 mutex_unlock(&sdata->local->sta_mtx); 972 973 return ret; 974 } 975 976 static void sta_info_cleanup(unsigned long data) 977 { 978 struct ieee80211_local *local = (struct ieee80211_local *) data; 979 struct sta_info *sta; 980 bool timer_needed = false; 981 982 rcu_read_lock(); 983 list_for_each_entry_rcu(sta, &local->sta_list, list) 984 if (sta_info_cleanup_expire_buffered(local, sta)) 985 timer_needed = true; 986 rcu_read_unlock(); 987 988 if (local->quiescing) 989 return; 990 991 if (!timer_needed) 992 return; 993 994 mod_timer(&local->sta_cleanup, 995 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL)); 996 } 997 998 void sta_info_init(struct ieee80211_local *local) 999 { 1000 spin_lock_init(&local->sta_lock); 1001 mutex_init(&local->sta_mtx); 1002 INIT_LIST_HEAD(&local->sta_list); 1003 INIT_LIST_HEAD(&local->sta_pending_list); 1004 INIT_WORK(&local->sta_finish_work, sta_info_finish_work); 1005 1006 setup_timer(&local->sta_cleanup, sta_info_cleanup, 1007 (unsigned long)local); 1008 } 1009 1010 void sta_info_stop(struct ieee80211_local *local) 1011 { 1012 del_timer(&local->sta_cleanup); 1013 sta_info_flush(local, NULL); 1014 } 1015 1016 /** 1017 * sta_info_flush - flush matching STA entries from the STA table 1018 * 1019 * Returns the number of removed STA entries. 1020 * 1021 * @local: local interface data 1022 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs 1023 */ 1024 int sta_info_flush(struct ieee80211_local *local, 1025 struct ieee80211_sub_if_data *sdata) 1026 { 1027 struct sta_info *sta, *tmp; 1028 int ret = 0; 1029 1030 might_sleep(); 1031 1032 mutex_lock(&local->sta_mtx); 1033 1034 sta_info_finish_pending(local); 1035 1036 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 1037 if (!sdata || sdata == sta->sdata) 1038 WARN_ON(__sta_info_destroy(sta)); 1039 } 1040 mutex_unlock(&local->sta_mtx); 1041 1042 return ret; 1043 } 1044 1045 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata, 1046 unsigned long exp_time) 1047 { 1048 struct ieee80211_local *local = sdata->local; 1049 struct sta_info *sta, *tmp; 1050 1051 mutex_lock(&local->sta_mtx); 1052 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) 1053 if (time_after(jiffies, sta->last_rx + exp_time)) { 1054 #ifdef CONFIG_MAC80211_IBSS_DEBUG 1055 printk(KERN_DEBUG "%s: expiring inactive STA %pM\n", 1056 sdata->name, sta->sta.addr); 1057 #endif 1058 WARN_ON(__sta_info_destroy(sta)); 1059 } 1060 mutex_unlock(&local->sta_mtx); 1061 } 1062 1063 struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw, 1064 const u8 *addr, 1065 const u8 *localaddr) 1066 { 1067 struct sta_info *sta, *nxt; 1068 1069 /* 1070 * Just return a random station if localaddr is NULL 1071 * ... first in list. 1072 */ 1073 for_each_sta_info(hw_to_local(hw), addr, sta, nxt) { 1074 if (localaddr && 1075 compare_ether_addr(sta->sdata->vif.addr, localaddr) != 0) 1076 continue; 1077 if (!sta->uploaded) 1078 return NULL; 1079 return &sta->sta; 1080 } 1081 1082 return NULL; 1083 } 1084 EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr); 1085 1086 struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif, 1087 const u8 *addr) 1088 { 1089 struct sta_info *sta; 1090 1091 if (!vif) 1092 return NULL; 1093 1094 sta = sta_info_get_bss(vif_to_sdata(vif), addr); 1095 if (!sta) 1096 return NULL; 1097 1098 if (!sta->uploaded) 1099 return NULL; 1100 1101 return &sta->sta; 1102 } 1103 EXPORT_SYMBOL(ieee80211_find_sta); 1104 1105 static void clear_sta_ps_flags(void *_sta) 1106 { 1107 struct sta_info *sta = _sta; 1108 1109 clear_sta_flags(sta, WLAN_STA_PS_DRIVER | WLAN_STA_PS_STA); 1110 } 1111 1112 /* powersave support code */ 1113 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) 1114 { 1115 struct ieee80211_sub_if_data *sdata = sta->sdata; 1116 struct ieee80211_local *local = sdata->local; 1117 struct sk_buff_head pending; 1118 int filtered = 0, buffered = 0, ac; 1119 1120 BUILD_BUG_ON(BITS_TO_LONGS(STA_TID_NUM) > 1); 1121 sta->driver_buffered_tids = 0; 1122 1123 if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS)) 1124 drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta); 1125 1126 skb_queue_head_init(&pending); 1127 1128 /* Send all buffered frames to the station */ 1129 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { 1130 int count = skb_queue_len(&pending), tmp; 1131 1132 skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending); 1133 tmp = skb_queue_len(&pending); 1134 filtered += tmp - count; 1135 count = tmp; 1136 1137 skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending); 1138 tmp = skb_queue_len(&pending); 1139 buffered += tmp - count; 1140 } 1141 1142 ieee80211_add_pending_skbs_fn(local, &pending, clear_sta_ps_flags, sta); 1143 1144 local->total_ps_buffered -= buffered; 1145 1146 sta_info_recalc_tim(sta); 1147 1148 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1149 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames " 1150 "since STA not sleeping anymore\n", sdata->name, 1151 sta->sta.addr, sta->sta.aid, filtered, buffered); 1152 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1153 } 1154 1155 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta) 1156 { 1157 struct ieee80211_sub_if_data *sdata = sta->sdata; 1158 struct ieee80211_local *local = sdata->local; 1159 struct sk_buff *skb = NULL; 1160 bool found = false; 1161 bool more_data = false; 1162 int ac; 1163 unsigned long driver_release_tids = 0; 1164 u8 ignore_for_response = sta->sta.uapsd_queues; 1165 1166 /* 1167 * If all ACs are delivery-enabled then we should reply 1168 * from any of them, if only some are enabled we reply 1169 * only from the non-enabled ones. 1170 */ 1171 if (ignore_for_response == BIT(IEEE80211_NUM_ACS) - 1) 1172 ignore_for_response = 0; 1173 1174 /* 1175 * Get response frame and more data bit for it. 1176 */ 1177 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) { 1178 unsigned long tids; 1179 1180 if (ignore_for_response & BIT(ac)) 1181 continue; 1182 1183 tids = ieee80211_tids_for_ac(ac); 1184 1185 if (!found) { 1186 driver_release_tids = sta->driver_buffered_tids & tids; 1187 if (driver_release_tids) { 1188 found = true; 1189 } else { 1190 skb = skb_dequeue(&sta->tx_filtered[ac]); 1191 if (!skb) { 1192 skb = skb_dequeue(&sta->ps_tx_buf[ac]); 1193 if (skb) 1194 local->total_ps_buffered--; 1195 } 1196 if (skb) 1197 found = true; 1198 } 1199 1200 /* 1201 * If the driver has data on more than one TID then 1202 * certainly there's more data if we release just a 1203 * single frame now (from a single TID). 1204 */ 1205 if (hweight16(driver_release_tids) > 1) { 1206 more_data = true; 1207 driver_release_tids = 1208 BIT(ffs(driver_release_tids) - 1); 1209 break; 1210 } 1211 } 1212 1213 if (!skb_queue_empty(&sta->tx_filtered[ac]) || 1214 !skb_queue_empty(&sta->ps_tx_buf[ac])) { 1215 more_data = true; 1216 break; 1217 } 1218 } 1219 1220 if (!found) { 1221 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1222 /* 1223 * FIXME: This can be the result of a race condition between 1224 * us expiring a frame and the station polling for it. 1225 * Should we send it a null-func frame indicating we 1226 * have nothing buffered for it? 1227 */ 1228 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even " 1229 "though there are no buffered frames for it\n", 1230 sdata->name, sta->sta.addr); 1231 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1232 1233 return; 1234 } 1235 1236 if (skb) { 1237 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 1238 struct ieee80211_hdr *hdr = 1239 (struct ieee80211_hdr *) skb->data; 1240 1241 /* 1242 * Tell TX path to send this frame even though the STA may 1243 * still remain is PS mode after this frame exchange. 1244 */ 1245 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE; 1246 1247 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 1248 printk(KERN_DEBUG "STA %pM aid %d: PS Poll\n", 1249 sta->sta.addr, sta->sta.aid); 1250 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 1251 1252 /* Use MoreData flag to indicate whether there are more 1253 * buffered frames for this STA */ 1254 if (!more_data) 1255 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 1256 else 1257 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 1258 1259 ieee80211_add_pending_skb(local, skb); 1260 1261 sta_info_recalc_tim(sta); 1262 } else { 1263 /* 1264 * We need to release a frame that is buffered somewhere in the 1265 * driver ... it'll have to handle that. 1266 * Note that, as per the comment above, it'll also have to see 1267 * if there is more than just one frame on the specific TID that 1268 * we're releasing from, and it needs to set the more-data bit 1269 * accordingly if we tell it that there's no more data. If we do 1270 * tell it there's more data, then of course the more-data bit 1271 * needs to be set anyway. 1272 */ 1273 drv_release_buffered_frames(local, sta, driver_release_tids, 1274 1, IEEE80211_FRAME_RELEASE_PSPOLL, 1275 more_data); 1276 1277 /* 1278 * Note that we don't recalculate the TIM bit here as it would 1279 * most likely have no effect at all unless the driver told us 1280 * that the TID became empty before returning here from the 1281 * release function. 1282 * Either way, however, when the driver tells us that the TID 1283 * became empty we'll do the TIM recalculation. 1284 */ 1285 } 1286 } 1287 1288 void ieee80211_sta_block_awake(struct ieee80211_hw *hw, 1289 struct ieee80211_sta *pubsta, bool block) 1290 { 1291 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 1292 1293 trace_api_sta_block_awake(sta->local, pubsta, block); 1294 1295 if (block) 1296 set_sta_flags(sta, WLAN_STA_PS_DRIVER); 1297 else if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) 1298 ieee80211_queue_work(hw, &sta->drv_unblock_wk); 1299 } 1300 EXPORT_SYMBOL(ieee80211_sta_block_awake); 1301 1302 void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta, 1303 u8 tid, bool buffered) 1304 { 1305 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 1306 1307 if (WARN_ON(tid >= STA_TID_NUM)) 1308 return; 1309 1310 if (buffered) 1311 set_bit(tid, &sta->driver_buffered_tids); 1312 else 1313 clear_bit(tid, &sta->driver_buffered_tids); 1314 1315 sta_info_recalc_tim(sta); 1316 } 1317 EXPORT_SYMBOL(ieee80211_sta_set_buffered); 1318