sta_info.c revision 0fb9a9ec27718fbf7fa3153bc94becefb716ceeb
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 assocation 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 imediately 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 */ 65static int sta_info_hash_del(struct ieee80211_local *local, 66 struct sta_info *sta) 67{ 68 struct sta_info *s; 69 70 s = local->sta_hash[STA_HASH(sta->sta.addr)]; 71 if (!s) 72 return -ENOENT; 73 if (s == sta) { 74 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], 75 s->hnext); 76 return 0; 77 } 78 79 while (s->hnext && s->hnext != sta) 80 s = s->hnext; 81 if (s->hnext) { 82 rcu_assign_pointer(s->hnext, sta->hnext); 83 return 0; 84 } 85 86 return -ENOENT; 87} 88 89/* protected by RCU */ 90struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata, 91 const u8 *addr) 92{ 93 struct ieee80211_local *local = sdata->local; 94 struct sta_info *sta; 95 96 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], 97 rcu_read_lock_held() || 98 lockdep_is_held(&local->sta_lock) || 99 lockdep_is_held(&local->sta_mtx)); 100 while (sta) { 101 if (sta->sdata == sdata && 102 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 103 break; 104 sta = rcu_dereference_check(sta->hnext, 105 rcu_read_lock_held() || 106 lockdep_is_held(&local->sta_lock) || 107 lockdep_is_held(&local->sta_mtx)); 108 } 109 return sta; 110} 111 112/* 113 * Get sta info either from the specified interface 114 * or from one of its vlans 115 */ 116struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata, 117 const u8 *addr) 118{ 119 struct ieee80211_local *local = sdata->local; 120 struct sta_info *sta; 121 122 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)], 123 rcu_read_lock_held() || 124 lockdep_is_held(&local->sta_lock) || 125 lockdep_is_held(&local->sta_mtx)); 126 while (sta) { 127 if ((sta->sdata == sdata || 128 sta->sdata->bss == sdata->bss) && 129 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 130 break; 131 sta = rcu_dereference_check(sta->hnext, 132 rcu_read_lock_held() || 133 lockdep_is_held(&local->sta_lock) || 134 lockdep_is_held(&local->sta_mtx)); 135 } 136 return sta; 137} 138 139struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata, 140 int idx) 141{ 142 struct ieee80211_local *local = sdata->local; 143 struct sta_info *sta; 144 int i = 0; 145 146 list_for_each_entry_rcu(sta, &local->sta_list, list) { 147 if (sdata != sta->sdata) 148 continue; 149 if (i < idx) { 150 ++i; 151 continue; 152 } 153 return sta; 154 } 155 156 return NULL; 157} 158 159/** 160 * __sta_info_free - internal STA free helper 161 * 162 * @local: pointer to the global information 163 * @sta: STA info to free 164 * 165 * This function must undo everything done by sta_info_alloc() 166 * that may happen before sta_info_insert(). 167 */ 168static void __sta_info_free(struct ieee80211_local *local, 169 struct sta_info *sta) 170{ 171 if (sta->rate_ctrl) { 172 rate_control_free_sta(sta); 173 rate_control_put(sta->rate_ctrl); 174 } 175 176#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 177 wiphy_debug(local->hw.wiphy, "Destroyed STA %pM\n", sta->sta.addr); 178#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 179 180 kfree(sta); 181} 182 183/* Caller must hold local->sta_lock */ 184static void sta_info_hash_add(struct ieee80211_local *local, 185 struct sta_info *sta) 186{ 187 sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)]; 188 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta); 189} 190 191static void sta_unblock(struct work_struct *wk) 192{ 193 struct sta_info *sta; 194 195 sta = container_of(wk, struct sta_info, drv_unblock_wk); 196 197 if (sta->dead) 198 return; 199 200 if (!test_sta_flags(sta, WLAN_STA_PS_STA)) 201 ieee80211_sta_ps_deliver_wakeup(sta); 202 else if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL)) 203 ieee80211_sta_ps_deliver_poll_response(sta); 204} 205 206static int sta_prepare_rate_control(struct ieee80211_local *local, 207 struct sta_info *sta, gfp_t gfp) 208{ 209 if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) 210 return 0; 211 212 sta->rate_ctrl = rate_control_get(local->rate_ctrl); 213 sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, 214 &sta->sta, gfp); 215 if (!sta->rate_ctrl_priv) { 216 rate_control_put(sta->rate_ctrl); 217 return -ENOMEM; 218 } 219 220 return 0; 221} 222 223struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, 224 u8 *addr, gfp_t gfp) 225{ 226 struct ieee80211_local *local = sdata->local; 227 struct sta_info *sta; 228 int i; 229 230 sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); 231 if (!sta) 232 return NULL; 233 234 spin_lock_init(&sta->lock); 235 spin_lock_init(&sta->flaglock); 236 INIT_WORK(&sta->drv_unblock_wk, sta_unblock); 237 INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work); 238 mutex_init(&sta->ampdu_mlme.mtx); 239 240 memcpy(sta->sta.addr, addr, ETH_ALEN); 241 sta->local = local; 242 sta->sdata = sdata; 243 244 if (sta_prepare_rate_control(local, sta, gfp)) { 245 kfree(sta); 246 return NULL; 247 } 248 249 for (i = 0; i < STA_TID_NUM; i++) { 250 /* 251 * timer_to_tid must be initialized with identity mapping 252 * to enable session_timer's data differentiation. See 253 * sta_rx_agg_session_timer_expired for usage. 254 */ 255 sta->timer_to_tid[i] = i; 256 } 257 skb_queue_head_init(&sta->ps_tx_buf); 258 skb_queue_head_init(&sta->tx_filtered); 259 260 for (i = 0; i < NUM_RX_DATA_QUEUES; i++) 261 sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX); 262 263#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 264 wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr); 265#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 266 267#ifdef CONFIG_MAC80211_MESH 268 sta->plink_state = PLINK_LISTEN; 269 init_timer(&sta->plink_timer); 270#endif 271 272 return sta; 273} 274 275static int sta_info_finish_insert(struct sta_info *sta, bool async) 276{ 277 struct ieee80211_local *local = sta->local; 278 struct ieee80211_sub_if_data *sdata = sta->sdata; 279 struct station_info sinfo; 280 unsigned long flags; 281 int err = 0; 282 283 WARN_ON(!mutex_is_locked(&local->sta_mtx)); 284 285 /* notify driver */ 286 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 287 sdata = container_of(sdata->bss, 288 struct ieee80211_sub_if_data, 289 u.ap); 290 err = drv_sta_add(local, sdata, &sta->sta); 291 if (err) { 292 if (!async) 293 return err; 294 printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to driver (%d)" 295 " - keeping it anyway.\n", 296 sdata->name, sta->sta.addr, err); 297 } else { 298 sta->uploaded = true; 299#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 300 if (async) 301 wiphy_debug(local->hw.wiphy, 302 "Finished adding IBSS STA %pM\n", 303 sta->sta.addr); 304#endif 305 } 306 307 sdata = sta->sdata; 308 309 if (!async) { 310 local->num_sta++; 311 local->sta_generation++; 312 smp_mb(); 313 314 /* make the station visible */ 315 spin_lock_irqsave(&local->sta_lock, flags); 316 sta_info_hash_add(local, sta); 317 spin_unlock_irqrestore(&local->sta_lock, flags); 318 } 319 320 list_add(&sta->list, &local->sta_list); 321 322 ieee80211_sta_debugfs_add(sta); 323 rate_control_add_sta_debugfs(sta); 324 325 sinfo.filled = 0; 326 sinfo.generation = local->sta_generation; 327 cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL); 328 329 330 return 0; 331} 332 333static void sta_info_finish_pending(struct ieee80211_local *local) 334{ 335 struct sta_info *sta; 336 unsigned long flags; 337 338 spin_lock_irqsave(&local->sta_lock, flags); 339 while (!list_empty(&local->sta_pending_list)) { 340 sta = list_first_entry(&local->sta_pending_list, 341 struct sta_info, list); 342 list_del(&sta->list); 343 spin_unlock_irqrestore(&local->sta_lock, flags); 344 345 sta_info_finish_insert(sta, true); 346 347 spin_lock_irqsave(&local->sta_lock, flags); 348 } 349 spin_unlock_irqrestore(&local->sta_lock, flags); 350} 351 352static void sta_info_finish_work(struct work_struct *work) 353{ 354 struct ieee80211_local *local = 355 container_of(work, struct ieee80211_local, sta_finish_work); 356 357 mutex_lock(&local->sta_mtx); 358 sta_info_finish_pending(local); 359 mutex_unlock(&local->sta_mtx); 360} 361 362int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU) 363{ 364 struct ieee80211_local *local = sta->local; 365 struct ieee80211_sub_if_data *sdata = sta->sdata; 366 unsigned long flags; 367 int err = 0; 368 369 /* 370 * Can't be a WARN_ON because it can be triggered through a race: 371 * something inserts a STA (on one CPU) without holding the RTNL 372 * and another CPU turns off the net device. 373 */ 374 if (unlikely(!ieee80211_sdata_running(sdata))) { 375 err = -ENETDOWN; 376 rcu_read_lock(); 377 goto out_free; 378 } 379 380 if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 || 381 is_multicast_ether_addr(sta->sta.addr))) { 382 err = -EINVAL; 383 rcu_read_lock(); 384 goto out_free; 385 } 386 387 /* 388 * In ad-hoc mode, we sometimes need to insert stations 389 * from tasklet context from the RX path. To avoid races, 390 * always do so in that case -- see the comment below. 391 */ 392 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 393 spin_lock_irqsave(&local->sta_lock, flags); 394 /* check if STA exists already */ 395 if (sta_info_get_bss(sdata, sta->sta.addr)) { 396 spin_unlock_irqrestore(&local->sta_lock, flags); 397 rcu_read_lock(); 398 err = -EEXIST; 399 goto out_free; 400 } 401 402 local->num_sta++; 403 local->sta_generation++; 404 smp_mb(); 405 sta_info_hash_add(local, sta); 406 407 list_add_tail(&sta->list, &local->sta_pending_list); 408 409 rcu_read_lock(); 410 spin_unlock_irqrestore(&local->sta_lock, flags); 411 412#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 413 wiphy_debug(local->hw.wiphy, "Added IBSS STA %pM\n", 414 sta->sta.addr); 415#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 416 417 ieee80211_queue_work(&local->hw, &local->sta_finish_work); 418 419 return 0; 420 } 421 422 /* 423 * On first glance, this will look racy, because the code 424 * below this point, which inserts a station with sleeping, 425 * unlocks the sta_lock between checking existence in the 426 * hash table and inserting into it. 427 * 428 * However, it is not racy against itself because it keeps 429 * the mutex locked. It still seems to race against the 430 * above code that atomically inserts the station... That, 431 * however, is not true because the above code can only 432 * be invoked for IBSS interfaces, and the below code will 433 * not be -- and the two do not race against each other as 434 * the hash table also keys off the interface. 435 */ 436 437 might_sleep(); 438 439 mutex_lock(&local->sta_mtx); 440 441 spin_lock_irqsave(&local->sta_lock, flags); 442 /* check if STA exists already */ 443 if (sta_info_get_bss(sdata, sta->sta.addr)) { 444 spin_unlock_irqrestore(&local->sta_lock, flags); 445 mutex_unlock(&local->sta_mtx); 446 rcu_read_lock(); 447 err = -EEXIST; 448 goto out_free; 449 } 450 451 spin_unlock_irqrestore(&local->sta_lock, flags); 452 453 err = sta_info_finish_insert(sta, false); 454 if (err) { 455 mutex_unlock(&local->sta_mtx); 456 rcu_read_lock(); 457 goto out_free; 458 } 459 460#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 461 wiphy_debug(local->hw.wiphy, "Inserted STA %pM\n", sta->sta.addr); 462#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 463 464 /* move reference to rcu-protected */ 465 rcu_read_lock(); 466 mutex_unlock(&local->sta_mtx); 467 468 if (ieee80211_vif_is_mesh(&sdata->vif)) 469 mesh_accept_plinks_update(sdata); 470 471 return 0; 472 out_free: 473 BUG_ON(!err); 474 __sta_info_free(local, sta); 475 return err; 476} 477 478int sta_info_insert(struct sta_info *sta) 479{ 480 int err = sta_info_insert_rcu(sta); 481 482 rcu_read_unlock(); 483 484 return err; 485} 486 487static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid) 488{ 489 /* 490 * This format has been mandated by the IEEE specifications, 491 * so this line may not be changed to use the __set_bit() format. 492 */ 493 bss->tim[aid / 8] |= (1 << (aid % 8)); 494} 495 496static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid) 497{ 498 /* 499 * This format has been mandated by the IEEE specifications, 500 * so this line may not be changed to use the __clear_bit() format. 501 */ 502 bss->tim[aid / 8] &= ~(1 << (aid % 8)); 503} 504 505static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss, 506 struct sta_info *sta) 507{ 508 BUG_ON(!bss); 509 510 __bss_tim_set(bss, sta->sta.aid); 511 512 if (sta->local->ops->set_tim) { 513 sta->local->tim_in_locked_section = true; 514 drv_set_tim(sta->local, &sta->sta, true); 515 sta->local->tim_in_locked_section = false; 516 } 517} 518 519void sta_info_set_tim_bit(struct sta_info *sta) 520{ 521 unsigned long flags; 522 523 BUG_ON(!sta->sdata->bss); 524 525 spin_lock_irqsave(&sta->local->sta_lock, flags); 526 __sta_info_set_tim_bit(sta->sdata->bss, sta); 527 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 528} 529 530static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss, 531 struct sta_info *sta) 532{ 533 BUG_ON(!bss); 534 535 __bss_tim_clear(bss, sta->sta.aid); 536 537 if (sta->local->ops->set_tim) { 538 sta->local->tim_in_locked_section = true; 539 drv_set_tim(sta->local, &sta->sta, false); 540 sta->local->tim_in_locked_section = false; 541 } 542} 543 544void sta_info_clear_tim_bit(struct sta_info *sta) 545{ 546 unsigned long flags; 547 548 BUG_ON(!sta->sdata->bss); 549 550 spin_lock_irqsave(&sta->local->sta_lock, flags); 551 __sta_info_clear_tim_bit(sta->sdata->bss, sta); 552 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 553} 554 555static int sta_info_buffer_expired(struct sta_info *sta, 556 struct sk_buff *skb) 557{ 558 struct ieee80211_tx_info *info; 559 int timeout; 560 561 if (!skb) 562 return 0; 563 564 info = IEEE80211_SKB_CB(skb); 565 566 /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */ 567 timeout = (sta->listen_interval * 568 sta->sdata->vif.bss_conf.beacon_int * 569 32 / 15625) * HZ; 570 if (timeout < STA_TX_BUFFER_EXPIRE) 571 timeout = STA_TX_BUFFER_EXPIRE; 572 return time_after(jiffies, info->control.jiffies + timeout); 573} 574 575 576static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local, 577 struct sta_info *sta) 578{ 579 unsigned long flags; 580 struct sk_buff *skb; 581 struct ieee80211_sub_if_data *sdata; 582 583 if (skb_queue_empty(&sta->ps_tx_buf)) 584 return false; 585 586 for (;;) { 587 spin_lock_irqsave(&sta->ps_tx_buf.lock, flags); 588 skb = skb_peek(&sta->ps_tx_buf); 589 if (sta_info_buffer_expired(sta, skb)) 590 skb = __skb_dequeue(&sta->ps_tx_buf); 591 else 592 skb = NULL; 593 spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags); 594 595 if (!skb) 596 break; 597 598 sdata = sta->sdata; 599 local->total_ps_buffered--; 600#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 601 printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n", 602 sta->sta.addr); 603#endif 604 dev_kfree_skb(skb); 605 606 if (skb_queue_empty(&sta->ps_tx_buf)) 607 sta_info_clear_tim_bit(sta); 608 } 609 610 return true; 611} 612 613static int __must_check __sta_info_destroy(struct sta_info *sta) 614{ 615 struct ieee80211_local *local; 616 struct ieee80211_sub_if_data *sdata; 617 struct sk_buff *skb; 618 unsigned long flags; 619 int ret; 620 621 might_sleep(); 622 623 if (!sta) 624 return -ENOENT; 625 626 local = sta->local; 627 sdata = sta->sdata; 628 629 /* 630 * Before removing the station from the driver and 631 * rate control, it might still start new aggregation 632 * sessions -- block that to make sure the tear-down 633 * will be sufficient. 634 */ 635 set_sta_flags(sta, WLAN_STA_BLOCK_BA); 636 ieee80211_sta_tear_down_BA_sessions(sta); 637 638 spin_lock_irqsave(&local->sta_lock, flags); 639 ret = sta_info_hash_del(local, sta); 640 /* this might still be the pending list ... which is fine */ 641 if (!ret) 642 list_del(&sta->list); 643 spin_unlock_irqrestore(&local->sta_lock, flags); 644 if (ret) 645 return ret; 646 647 if (sta->key) { 648 ieee80211_key_free(local, sta->key); 649 WARN_ON(sta->key); 650 } 651 652 sta->dead = true; 653 654 if (test_and_clear_sta_flags(sta, 655 WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) { 656 BUG_ON(!sdata->bss); 657 658 atomic_dec(&sdata->bss->num_sta_ps); 659 __sta_info_clear_tim_bit(sdata->bss, sta); 660 } 661 662 local->num_sta--; 663 local->sta_generation++; 664 665 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 666 rcu_assign_pointer(sdata->u.vlan.sta, NULL); 667 668 if (sta->uploaded) { 669 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 670 sdata = container_of(sdata->bss, 671 struct ieee80211_sub_if_data, 672 u.ap); 673 drv_sta_remove(local, sdata, &sta->sta); 674 sdata = sta->sdata; 675 } 676 677 /* 678 * At this point, after we wait for an RCU grace period, 679 * neither mac80211 nor the driver can reference this 680 * sta struct any more except by still existing timers 681 * associated with this station that we clean up below. 682 */ 683 synchronize_rcu(); 684 685#ifdef CONFIG_MAC80211_MESH 686 if (ieee80211_vif_is_mesh(&sdata->vif)) 687 mesh_accept_plinks_update(sdata); 688#endif 689 690#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 691 wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr); 692#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 693 cancel_work_sync(&sta->drv_unblock_wk); 694 695 rate_control_remove_sta_debugfs(sta); 696 ieee80211_sta_debugfs_remove(sta); 697 698#ifdef CONFIG_MAC80211_MESH 699 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) { 700 mesh_plink_deactivate(sta); 701 del_timer_sync(&sta->plink_timer); 702 } 703#endif 704 705 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { 706 local->total_ps_buffered--; 707 dev_kfree_skb_any(skb); 708 } 709 710 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) 711 dev_kfree_skb_any(skb); 712 713 __sta_info_free(local, sta); 714 715 return 0; 716} 717 718int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr) 719{ 720 struct sta_info *sta; 721 int ret; 722 723 mutex_lock(&sdata->local->sta_mtx); 724 sta = sta_info_get(sdata, addr); 725 ret = __sta_info_destroy(sta); 726 mutex_unlock(&sdata->local->sta_mtx); 727 728 return ret; 729} 730 731int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata, 732 const u8 *addr) 733{ 734 struct sta_info *sta; 735 int ret; 736 737 mutex_lock(&sdata->local->sta_mtx); 738 sta = sta_info_get_bss(sdata, addr); 739 ret = __sta_info_destroy(sta); 740 mutex_unlock(&sdata->local->sta_mtx); 741 742 return ret; 743} 744 745static void sta_info_cleanup(unsigned long data) 746{ 747 struct ieee80211_local *local = (struct ieee80211_local *) data; 748 struct sta_info *sta; 749 bool timer_needed = false; 750 751 rcu_read_lock(); 752 list_for_each_entry_rcu(sta, &local->sta_list, list) 753 if (sta_info_cleanup_expire_buffered(local, sta)) 754 timer_needed = true; 755 rcu_read_unlock(); 756 757 if (local->quiescing) 758 return; 759 760 if (!timer_needed) 761 return; 762 763 local->sta_cleanup.expires = 764 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); 765 add_timer(&local->sta_cleanup); 766} 767 768void sta_info_init(struct ieee80211_local *local) 769{ 770 spin_lock_init(&local->sta_lock); 771 mutex_init(&local->sta_mtx); 772 INIT_LIST_HEAD(&local->sta_list); 773 INIT_LIST_HEAD(&local->sta_pending_list); 774 INIT_WORK(&local->sta_finish_work, sta_info_finish_work); 775 776 setup_timer(&local->sta_cleanup, sta_info_cleanup, 777 (unsigned long)local); 778 local->sta_cleanup.expires = 779 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); 780} 781 782int sta_info_start(struct ieee80211_local *local) 783{ 784 add_timer(&local->sta_cleanup); 785 return 0; 786} 787 788void sta_info_stop(struct ieee80211_local *local) 789{ 790 del_timer(&local->sta_cleanup); 791 sta_info_flush(local, NULL); 792} 793 794/** 795 * sta_info_flush - flush matching STA entries from the STA table 796 * 797 * Returns the number of removed STA entries. 798 * 799 * @local: local interface data 800 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs 801 */ 802int sta_info_flush(struct ieee80211_local *local, 803 struct ieee80211_sub_if_data *sdata) 804{ 805 struct sta_info *sta, *tmp; 806 int ret = 0; 807 808 might_sleep(); 809 810 mutex_lock(&local->sta_mtx); 811 812 sta_info_finish_pending(local); 813 814 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 815 if (!sdata || sdata == sta->sdata) 816 WARN_ON(__sta_info_destroy(sta)); 817 } 818 mutex_unlock(&local->sta_mtx); 819 820 return ret; 821} 822 823void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata, 824 unsigned long exp_time) 825{ 826 struct ieee80211_local *local = sdata->local; 827 struct sta_info *sta, *tmp; 828 829 mutex_lock(&local->sta_mtx); 830 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) 831 if (time_after(jiffies, sta->last_rx + exp_time)) { 832#ifdef CONFIG_MAC80211_IBSS_DEBUG 833 printk(KERN_DEBUG "%s: expiring inactive STA %pM\n", 834 sdata->name, sta->sta.addr); 835#endif 836 WARN_ON(__sta_info_destroy(sta)); 837 } 838 mutex_unlock(&local->sta_mtx); 839} 840 841struct ieee80211_sta *ieee80211_find_sta_by_hw(struct ieee80211_hw *hw, 842 const u8 *addr) 843{ 844 struct sta_info *sta, *nxt; 845 846 /* Just return a random station ... first in list ... */ 847 for_each_sta_info(hw_to_local(hw), addr, sta, nxt) { 848 if (!sta->uploaded) 849 return NULL; 850 return &sta->sta; 851 } 852 853 return NULL; 854} 855EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_hw); 856 857struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif, 858 const u8 *addr) 859{ 860 struct sta_info *sta; 861 862 if (!vif) 863 return NULL; 864 865 sta = sta_info_get_bss(vif_to_sdata(vif), addr); 866 if (!sta) 867 return NULL; 868 869 if (!sta->uploaded) 870 return NULL; 871 872 return &sta->sta; 873} 874EXPORT_SYMBOL(ieee80211_find_sta); 875 876/* powersave support code */ 877void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) 878{ 879 struct ieee80211_sub_if_data *sdata = sta->sdata; 880 struct ieee80211_local *local = sdata->local; 881 int sent, buffered; 882 883 drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta); 884 885 if (!skb_queue_empty(&sta->ps_tx_buf)) 886 sta_info_clear_tim_bit(sta); 887 888 /* Send all buffered frames to the station */ 889 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered); 890 buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf); 891 sent += buffered; 892 local->total_ps_buffered -= buffered; 893 894#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 895 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames " 896 "since STA not sleeping anymore\n", sdata->name, 897 sta->sta.addr, sta->sta.aid, sent - buffered, buffered); 898#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 899} 900 901void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta) 902{ 903 struct ieee80211_sub_if_data *sdata = sta->sdata; 904 struct ieee80211_local *local = sdata->local; 905 struct sk_buff *skb; 906 int no_pending_pkts; 907 908 skb = skb_dequeue(&sta->tx_filtered); 909 if (!skb) { 910 skb = skb_dequeue(&sta->ps_tx_buf); 911 if (skb) 912 local->total_ps_buffered--; 913 } 914 no_pending_pkts = skb_queue_empty(&sta->tx_filtered) && 915 skb_queue_empty(&sta->ps_tx_buf); 916 917 if (skb) { 918 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 919 struct ieee80211_hdr *hdr = 920 (struct ieee80211_hdr *) skb->data; 921 922 /* 923 * Tell TX path to send this frame even though the STA may 924 * still remain is PS mode after this frame exchange. 925 */ 926 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE; 927 928#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 929 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n", 930 sta->sta.addr, sta->sta.aid, 931 skb_queue_len(&sta->ps_tx_buf)); 932#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 933 934 /* Use MoreData flag to indicate whether there are more 935 * buffered frames for this STA */ 936 if (no_pending_pkts) 937 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 938 else 939 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 940 941 ieee80211_add_pending_skb(local, skb); 942 943 if (no_pending_pkts) 944 sta_info_clear_tim_bit(sta); 945#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 946 } else { 947 /* 948 * FIXME: This can be the result of a race condition between 949 * us expiring a frame and the station polling for it. 950 * Should we send it a null-func frame indicating we 951 * have nothing buffered for it? 952 */ 953 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even " 954 "though there are no buffered frames for it\n", 955 sdata->name, sta->sta.addr); 956#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 957 } 958} 959 960void ieee80211_sta_block_awake(struct ieee80211_hw *hw, 961 struct ieee80211_sta *pubsta, bool block) 962{ 963 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 964 965 trace_api_sta_block_awake(sta->local, pubsta, block); 966 967 if (block) 968 set_sta_flags(sta, WLAN_STA_PS_DRIVER); 969 else 970 ieee80211_queue_work(hw, &sta->drv_unblock_wk); 971} 972EXPORT_SYMBOL(ieee80211_sta_block_awake); 973