sta_info.c revision 38a679a52be13d5a0c766597ab823e06688d6e8e
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(local->sta_hash[STA_HASH(addr)]); 97 while (sta) { 98 if (sta->sdata == sdata && 99 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 100 break; 101 sta = rcu_dereference(sta->hnext); 102 } 103 return sta; 104} 105 106/* 107 * Get sta info either from the specified interface 108 * or from one of its vlans 109 */ 110struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata, 111 const u8 *addr) 112{ 113 struct ieee80211_local *local = sdata->local; 114 struct sta_info *sta; 115 116 sta = rcu_dereference(local->sta_hash[STA_HASH(addr)]); 117 while (sta) { 118 if ((sta->sdata == sdata || 119 sta->sdata->bss == sdata->bss) && 120 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) 121 break; 122 sta = rcu_dereference(sta->hnext); 123 } 124 return sta; 125} 126 127struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata, 128 int idx) 129{ 130 struct ieee80211_local *local = sdata->local; 131 struct sta_info *sta; 132 int i = 0; 133 134 list_for_each_entry_rcu(sta, &local->sta_list, list) { 135 if (sdata != sta->sdata) 136 continue; 137 if (i < idx) { 138 ++i; 139 continue; 140 } 141 return sta; 142 } 143 144 return NULL; 145} 146 147/** 148 * __sta_info_free - internal STA free helper 149 * 150 * @local: pointer to the global information 151 * @sta: STA info to free 152 * 153 * This function must undo everything done by sta_info_alloc() 154 * that may happen before sta_info_insert(). 155 */ 156static void __sta_info_free(struct ieee80211_local *local, 157 struct sta_info *sta) 158{ 159 if (sta->rate_ctrl) { 160 rate_control_free_sta(sta); 161 rate_control_put(sta->rate_ctrl); 162 } 163 164#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 165 printk(KERN_DEBUG "%s: Destroyed STA %pM\n", 166 wiphy_name(local->hw.wiphy), sta->sta.addr); 167#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 168 169 kfree(sta); 170} 171 172/* Caller must hold local->sta_lock */ 173static void sta_info_hash_add(struct ieee80211_local *local, 174 struct sta_info *sta) 175{ 176 sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)]; 177 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta); 178} 179 180static void sta_unblock(struct work_struct *wk) 181{ 182 struct sta_info *sta; 183 184 sta = container_of(wk, struct sta_info, drv_unblock_wk); 185 186 if (sta->dead) 187 return; 188 189 if (!test_sta_flags(sta, WLAN_STA_PS_STA)) 190 ieee80211_sta_ps_deliver_wakeup(sta); 191 else if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL)) 192 ieee80211_sta_ps_deliver_poll_response(sta); 193} 194 195static int sta_prepare_rate_control(struct ieee80211_local *local, 196 struct sta_info *sta, gfp_t gfp) 197{ 198 if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) 199 return 0; 200 201 sta->rate_ctrl = rate_control_get(local->rate_ctrl); 202 sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, 203 &sta->sta, gfp); 204 if (!sta->rate_ctrl_priv) { 205 rate_control_put(sta->rate_ctrl); 206 return -ENOMEM; 207 } 208 209 return 0; 210} 211 212struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, 213 u8 *addr, gfp_t gfp) 214{ 215 struct ieee80211_local *local = sdata->local; 216 struct sta_info *sta; 217 int i; 218 219 sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); 220 if (!sta) 221 return NULL; 222 223 spin_lock_init(&sta->lock); 224 spin_lock_init(&sta->flaglock); 225 INIT_WORK(&sta->drv_unblock_wk, sta_unblock); 226 227 memcpy(sta->sta.addr, addr, ETH_ALEN); 228 sta->local = local; 229 sta->sdata = sdata; 230 231 if (sta_prepare_rate_control(local, sta, gfp)) { 232 kfree(sta); 233 return NULL; 234 } 235 236 for (i = 0; i < STA_TID_NUM; i++) { 237 /* timer_to_tid must be initialized with identity mapping to 238 * enable session_timer's data differentiation. refer to 239 * sta_rx_agg_session_timer_expired for useage */ 240 sta->timer_to_tid[i] = i; 241 /* rx */ 242 sta->ampdu_mlme.tid_state_rx[i] = HT_AGG_STATE_IDLE; 243 sta->ampdu_mlme.tid_rx[i] = NULL; 244 /* tx */ 245 sta->ampdu_mlme.tid_state_tx[i] = HT_AGG_STATE_IDLE; 246 sta->ampdu_mlme.tid_tx[i] = NULL; 247 sta->ampdu_mlme.addba_req_num[i] = 0; 248 } 249 skb_queue_head_init(&sta->ps_tx_buf); 250 skb_queue_head_init(&sta->tx_filtered); 251 252 for (i = 0; i < NUM_RX_DATA_QUEUES; i++) 253 sta->last_seq_ctrl[i] = cpu_to_le16(USHORT_MAX); 254 255#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 256 printk(KERN_DEBUG "%s: Allocated STA %pM\n", 257 wiphy_name(local->hw.wiphy), sta->sta.addr); 258#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 259 260#ifdef CONFIG_MAC80211_MESH 261 sta->plink_state = PLINK_LISTEN; 262 init_timer(&sta->plink_timer); 263#endif 264 265 return sta; 266} 267 268static int sta_info_finish_insert(struct sta_info *sta, bool async) 269{ 270 struct ieee80211_local *local = sta->local; 271 struct ieee80211_sub_if_data *sdata = sta->sdata; 272 struct station_info sinfo; 273 unsigned long flags; 274 int err = 0; 275 276 WARN_ON(!mutex_is_locked(&local->sta_mtx)); 277 278 /* notify driver */ 279 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 280 sdata = container_of(sdata->bss, 281 struct ieee80211_sub_if_data, 282 u.ap); 283 err = drv_sta_add(local, sdata, &sta->sta); 284 if (err) { 285 if (!async) 286 return err; 287 printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to driver (%d)" 288 " - keeping it anyway.\n", 289 sdata->name, sta->sta.addr, err); 290 } else { 291 sta->uploaded = true; 292#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 293 if (async) 294 printk(KERN_DEBUG "%s: Finished adding IBSS STA %pM\n", 295 wiphy_name(local->hw.wiphy), sta->sta.addr); 296#endif 297 } 298 299 sdata = sta->sdata; 300 301 if (!async) { 302 local->num_sta++; 303 local->sta_generation++; 304 smp_mb(); 305 306 /* make the station visible */ 307 spin_lock_irqsave(&local->sta_lock, flags); 308 sta_info_hash_add(local, sta); 309 spin_unlock_irqrestore(&local->sta_lock, flags); 310 } 311 312 list_add(&sta->list, &local->sta_list); 313 314 ieee80211_sta_debugfs_add(sta); 315 rate_control_add_sta_debugfs(sta); 316 317 sinfo.filled = 0; 318 sinfo.generation = local->sta_generation; 319 cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL); 320 321 322 return 0; 323} 324 325static void sta_info_finish_pending(struct ieee80211_local *local) 326{ 327 struct sta_info *sta; 328 unsigned long flags; 329 330 spin_lock_irqsave(&local->sta_lock, flags); 331 while (!list_empty(&local->sta_pending_list)) { 332 sta = list_first_entry(&local->sta_pending_list, 333 struct sta_info, list); 334 list_del(&sta->list); 335 spin_unlock_irqrestore(&local->sta_lock, flags); 336 337 sta_info_finish_insert(sta, true); 338 339 spin_lock_irqsave(&local->sta_lock, flags); 340 } 341 spin_unlock_irqrestore(&local->sta_lock, flags); 342} 343 344static void sta_info_finish_work(struct work_struct *work) 345{ 346 struct ieee80211_local *local = 347 container_of(work, struct ieee80211_local, sta_finish_work); 348 349 mutex_lock(&local->sta_mtx); 350 sta_info_finish_pending(local); 351 mutex_unlock(&local->sta_mtx); 352} 353 354int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU) 355{ 356 struct ieee80211_local *local = sta->local; 357 struct ieee80211_sub_if_data *sdata = sta->sdata; 358 unsigned long flags; 359 int err = 0; 360 361 /* 362 * Can't be a WARN_ON because it can be triggered through a race: 363 * something inserts a STA (on one CPU) without holding the RTNL 364 * and another CPU turns off the net device. 365 */ 366 if (unlikely(!ieee80211_sdata_running(sdata))) { 367 err = -ENETDOWN; 368 rcu_read_lock(); 369 goto out_free; 370 } 371 372 if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 || 373 is_multicast_ether_addr(sta->sta.addr))) { 374 err = -EINVAL; 375 rcu_read_lock(); 376 goto out_free; 377 } 378 379 /* 380 * In ad-hoc mode, we sometimes need to insert stations 381 * from tasklet context from the RX path. To avoid races, 382 * always do so in that case -- see the comment below. 383 */ 384 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 385 spin_lock_irqsave(&local->sta_lock, flags); 386 /* check if STA exists already */ 387 if (sta_info_get_bss(sdata, sta->sta.addr)) { 388 spin_unlock_irqrestore(&local->sta_lock, flags); 389 rcu_read_lock(); 390 err = -EEXIST; 391 goto out_free; 392 } 393 394 local->num_sta++; 395 local->sta_generation++; 396 smp_mb(); 397 sta_info_hash_add(local, sta); 398 399 list_add_tail(&sta->list, &local->sta_pending_list); 400 401 rcu_read_lock(); 402 spin_unlock_irqrestore(&local->sta_lock, flags); 403 404#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 405 printk(KERN_DEBUG "%s: Added IBSS STA %pM\n", 406 wiphy_name(local->hw.wiphy), sta->sta.addr); 407#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 408 409 ieee80211_queue_work(&local->hw, &local->sta_finish_work); 410 411 return 0; 412 } 413 414 /* 415 * On first glance, this will look racy, because the code 416 * below this point, which inserts a station with sleeping, 417 * unlocks the sta_lock between checking existence in the 418 * hash table and inserting into it. 419 * 420 * However, it is not racy against itself because it keeps 421 * the mutex locked. It still seems to race against the 422 * above code that atomically inserts the station... That, 423 * however, is not true because the above code can only 424 * be invoked for IBSS interfaces, and the below code will 425 * not be -- and the two do not race against each other as 426 * the hash table also keys off the interface. 427 */ 428 429 might_sleep(); 430 431 mutex_lock(&local->sta_mtx); 432 433 spin_lock_irqsave(&local->sta_lock, flags); 434 /* check if STA exists already */ 435 if (sta_info_get_bss(sdata, sta->sta.addr)) { 436 spin_unlock_irqrestore(&local->sta_lock, flags); 437 mutex_unlock(&local->sta_mtx); 438 rcu_read_lock(); 439 err = -EEXIST; 440 goto out_free; 441 } 442 443 spin_unlock_irqrestore(&local->sta_lock, flags); 444 445 err = sta_info_finish_insert(sta, false); 446 if (err) { 447 mutex_unlock(&local->sta_mtx); 448 rcu_read_lock(); 449 goto out_free; 450 } 451 452#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 453 printk(KERN_DEBUG "%s: Inserted STA %pM\n", 454 wiphy_name(local->hw.wiphy), sta->sta.addr); 455#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 456 457 /* move reference to rcu-protected */ 458 rcu_read_lock(); 459 mutex_unlock(&local->sta_mtx); 460 461 if (ieee80211_vif_is_mesh(&sdata->vif)) 462 mesh_accept_plinks_update(sdata); 463 464 return 0; 465 out_free: 466 BUG_ON(!err); 467 __sta_info_free(local, sta); 468 return err; 469} 470 471int sta_info_insert(struct sta_info *sta) 472{ 473 int err = sta_info_insert_rcu(sta); 474 475 rcu_read_unlock(); 476 477 return err; 478} 479 480static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid) 481{ 482 /* 483 * This format has been mandated by the IEEE specifications, 484 * so this line may not be changed to use the __set_bit() format. 485 */ 486 bss->tim[aid / 8] |= (1 << (aid % 8)); 487} 488 489static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid) 490{ 491 /* 492 * This format has been mandated by the IEEE specifications, 493 * so this line may not be changed to use the __clear_bit() format. 494 */ 495 bss->tim[aid / 8] &= ~(1 << (aid % 8)); 496} 497 498static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss, 499 struct sta_info *sta) 500{ 501 BUG_ON(!bss); 502 503 __bss_tim_set(bss, sta->sta.aid); 504 505 if (sta->local->ops->set_tim) { 506 sta->local->tim_in_locked_section = true; 507 drv_set_tim(sta->local, &sta->sta, true); 508 sta->local->tim_in_locked_section = false; 509 } 510} 511 512void sta_info_set_tim_bit(struct sta_info *sta) 513{ 514 unsigned long flags; 515 516 BUG_ON(!sta->sdata->bss); 517 518 spin_lock_irqsave(&sta->local->sta_lock, flags); 519 __sta_info_set_tim_bit(sta->sdata->bss, sta); 520 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 521} 522 523static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss, 524 struct sta_info *sta) 525{ 526 BUG_ON(!bss); 527 528 __bss_tim_clear(bss, sta->sta.aid); 529 530 if (sta->local->ops->set_tim) { 531 sta->local->tim_in_locked_section = true; 532 drv_set_tim(sta->local, &sta->sta, false); 533 sta->local->tim_in_locked_section = false; 534 } 535} 536 537void sta_info_clear_tim_bit(struct sta_info *sta) 538{ 539 unsigned long flags; 540 541 BUG_ON(!sta->sdata->bss); 542 543 spin_lock_irqsave(&sta->local->sta_lock, flags); 544 __sta_info_clear_tim_bit(sta->sdata->bss, sta); 545 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 546} 547 548static int sta_info_buffer_expired(struct sta_info *sta, 549 struct sk_buff *skb) 550{ 551 struct ieee80211_tx_info *info; 552 int timeout; 553 554 if (!skb) 555 return 0; 556 557 info = IEEE80211_SKB_CB(skb); 558 559 /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */ 560 timeout = (sta->listen_interval * 561 sta->sdata->vif.bss_conf.beacon_int * 562 32 / 15625) * HZ; 563 if (timeout < STA_TX_BUFFER_EXPIRE) 564 timeout = STA_TX_BUFFER_EXPIRE; 565 return time_after(jiffies, info->control.jiffies + timeout); 566} 567 568 569static void sta_info_cleanup_expire_buffered(struct ieee80211_local *local, 570 struct sta_info *sta) 571{ 572 unsigned long flags; 573 struct sk_buff *skb; 574 struct ieee80211_sub_if_data *sdata; 575 576 if (skb_queue_empty(&sta->ps_tx_buf)) 577 return; 578 579 for (;;) { 580 spin_lock_irqsave(&sta->ps_tx_buf.lock, flags); 581 skb = skb_peek(&sta->ps_tx_buf); 582 if (sta_info_buffer_expired(sta, skb)) 583 skb = __skb_dequeue(&sta->ps_tx_buf); 584 else 585 skb = NULL; 586 spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags); 587 588 if (!skb) 589 break; 590 591 sdata = sta->sdata; 592 local->total_ps_buffered--; 593#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 594 printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n", 595 sta->sta.addr); 596#endif 597 dev_kfree_skb(skb); 598 599 if (skb_queue_empty(&sta->ps_tx_buf)) 600 sta_info_clear_tim_bit(sta); 601 } 602} 603 604static int __must_check __sta_info_destroy(struct sta_info *sta) 605{ 606 struct ieee80211_local *local; 607 struct ieee80211_sub_if_data *sdata; 608 struct sk_buff *skb; 609 unsigned long flags; 610 int ret, i; 611 612 might_sleep(); 613 614 if (!sta) 615 return -ENOENT; 616 617 local = sta->local; 618 sdata = sta->sdata; 619 620 spin_lock_irqsave(&local->sta_lock, flags); 621 ret = sta_info_hash_del(local, sta); 622 /* this might still be the pending list ... which is fine */ 623 if (!ret) 624 list_del(&sta->list); 625 spin_unlock_irqrestore(&local->sta_lock, flags); 626 if (ret) 627 return ret; 628 629 if (sta->key) { 630 ieee80211_key_free(sta->key); 631 /* 632 * We have only unlinked the key, and actually destroying it 633 * may mean it is removed from hardware which requires that 634 * the key->sta pointer is still valid, so flush the key todo 635 * list here. 636 * 637 * ieee80211_key_todo() will synchronize_rcu() so after this 638 * nothing can reference this sta struct any more. 639 */ 640 ieee80211_key_todo(); 641 642 WARN_ON(sta->key); 643 } 644 645 sta->dead = true; 646 647 if (test_and_clear_sta_flags(sta, 648 WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) { 649 BUG_ON(!sdata->bss); 650 651 atomic_dec(&sdata->bss->num_sta_ps); 652 __sta_info_clear_tim_bit(sdata->bss, sta); 653 } 654 655 local->num_sta--; 656 local->sta_generation++; 657 658 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 659 rcu_assign_pointer(sdata->u.vlan.sta, NULL); 660 661 if (sta->uploaded) { 662 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 663 sdata = container_of(sdata->bss, 664 struct ieee80211_sub_if_data, 665 u.ap); 666 drv_sta_remove(local, sdata, &sta->sta); 667 sdata = sta->sdata; 668 } 669 670#ifdef CONFIG_MAC80211_MESH 671 if (ieee80211_vif_is_mesh(&sdata->vif)) { 672 mesh_accept_plinks_update(sdata); 673 del_timer(&sta->plink_timer); 674 } 675#endif 676 677#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 678 printk(KERN_DEBUG "%s: Removed STA %pM\n", 679 wiphy_name(local->hw.wiphy), sta->sta.addr); 680#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 681 cancel_work_sync(&sta->drv_unblock_wk); 682 683 rate_control_remove_sta_debugfs(sta); 684 ieee80211_sta_debugfs_remove(sta); 685 686#ifdef CONFIG_MAC80211_MESH 687 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) { 688 mesh_plink_deactivate(sta); 689 del_timer_sync(&sta->plink_timer); 690 } 691#endif 692 693 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { 694 local->total_ps_buffered--; 695 dev_kfree_skb_any(skb); 696 } 697 698 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) 699 dev_kfree_skb_any(skb); 700 701 for (i = 0; i < STA_TID_NUM; i++) { 702 struct tid_ampdu_rx *tid_rx; 703 struct tid_ampdu_tx *tid_tx; 704 705 spin_lock_bh(&sta->lock); 706 tid_rx = sta->ampdu_mlme.tid_rx[i]; 707 /* Make sure timer won't free the tid_rx struct, see below */ 708 if (tid_rx) 709 tid_rx->shutdown = true; 710 711 spin_unlock_bh(&sta->lock); 712 713 /* 714 * Outside spinlock - shutdown is true now so that the timer 715 * won't free tid_rx, we have to do that now. Can't let the 716 * timer do it because we have to sync the timer outside the 717 * lock that it takes itself. 718 */ 719 if (tid_rx) { 720 del_timer_sync(&tid_rx->session_timer); 721 kfree(tid_rx); 722 } 723 724 /* 725 * No need to do such complications for TX agg sessions, the 726 * path leading to freeing the tid_tx struct goes via a call 727 * from the driver, and thus needs to look up the sta struct 728 * again, which cannot be found when we get here. Hence, we 729 * just need to delete the timer and free the aggregation 730 * info; we won't be telling the peer about it then but that 731 * doesn't matter if we're not talking to it again anyway. 732 */ 733 tid_tx = sta->ampdu_mlme.tid_tx[i]; 734 if (tid_tx) { 735 del_timer_sync(&tid_tx->addba_resp_timer); 736 /* 737 * STA removed while aggregation session being 738 * started? Bit odd, but purge frames anyway. 739 */ 740 skb_queue_purge(&tid_tx->pending); 741 kfree(tid_tx); 742 } 743 } 744 745 __sta_info_free(local, sta); 746 747 return 0; 748} 749 750int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr) 751{ 752 struct sta_info *sta; 753 int ret; 754 755 mutex_lock(&sdata->local->sta_mtx); 756 sta = sta_info_get(sdata, addr); 757 ret = __sta_info_destroy(sta); 758 mutex_unlock(&sdata->local->sta_mtx); 759 760 return ret; 761} 762 763int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata, 764 const u8 *addr) 765{ 766 struct sta_info *sta; 767 int ret; 768 769 mutex_lock(&sdata->local->sta_mtx); 770 sta = sta_info_get_bss(sdata, addr); 771 ret = __sta_info_destroy(sta); 772 mutex_unlock(&sdata->local->sta_mtx); 773 774 return ret; 775} 776 777static void sta_info_cleanup(unsigned long data) 778{ 779 struct ieee80211_local *local = (struct ieee80211_local *) data; 780 struct sta_info *sta; 781 782 rcu_read_lock(); 783 list_for_each_entry_rcu(sta, &local->sta_list, list) 784 sta_info_cleanup_expire_buffered(local, sta); 785 rcu_read_unlock(); 786 787 if (local->quiescing) 788 return; 789 790 local->sta_cleanup.expires = 791 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); 792 add_timer(&local->sta_cleanup); 793} 794 795void sta_info_init(struct ieee80211_local *local) 796{ 797 spin_lock_init(&local->sta_lock); 798 mutex_init(&local->sta_mtx); 799 INIT_LIST_HEAD(&local->sta_list); 800 INIT_LIST_HEAD(&local->sta_pending_list); 801 INIT_WORK(&local->sta_finish_work, sta_info_finish_work); 802 803 setup_timer(&local->sta_cleanup, sta_info_cleanup, 804 (unsigned long)local); 805 local->sta_cleanup.expires = 806 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); 807} 808 809int sta_info_start(struct ieee80211_local *local) 810{ 811 add_timer(&local->sta_cleanup); 812 return 0; 813} 814 815void sta_info_stop(struct ieee80211_local *local) 816{ 817 del_timer(&local->sta_cleanup); 818 sta_info_flush(local, NULL); 819} 820 821/** 822 * sta_info_flush - flush matching STA entries from the STA table 823 * 824 * Returns the number of removed STA entries. 825 * 826 * @local: local interface data 827 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs 828 */ 829int sta_info_flush(struct ieee80211_local *local, 830 struct ieee80211_sub_if_data *sdata) 831{ 832 struct sta_info *sta, *tmp; 833 int ret = 0; 834 835 might_sleep(); 836 837 mutex_lock(&local->sta_mtx); 838 839 sta_info_finish_pending(local); 840 841 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 842 if (!sdata || sdata == sta->sdata) 843 WARN_ON(__sta_info_destroy(sta)); 844 } 845 mutex_unlock(&local->sta_mtx); 846 847 return ret; 848} 849 850void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata, 851 unsigned long exp_time) 852{ 853 struct ieee80211_local *local = sdata->local; 854 struct sta_info *sta, *tmp; 855 856 mutex_lock(&local->sta_mtx); 857 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) 858 if (time_after(jiffies, sta->last_rx + exp_time)) { 859#ifdef CONFIG_MAC80211_IBSS_DEBUG 860 printk(KERN_DEBUG "%s: expiring inactive STA %pM\n", 861 sdata->name, sta->sta.addr); 862#endif 863 WARN_ON(__sta_info_destroy(sta)); 864 } 865 mutex_unlock(&local->sta_mtx); 866} 867 868struct ieee80211_sta *ieee80211_find_sta_by_hw(struct ieee80211_hw *hw, 869 const u8 *addr) 870{ 871 struct sta_info *sta, *nxt; 872 873 /* Just return a random station ... first in list ... */ 874 for_each_sta_info(hw_to_local(hw), addr, sta, nxt) 875 return &sta->sta; 876 return NULL; 877} 878EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_hw); 879 880struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif, 881 const u8 *addr) 882{ 883 struct ieee80211_sub_if_data *sdata; 884 885 if (!vif) 886 return NULL; 887 888 sdata = vif_to_sdata(vif); 889 890 return ieee80211_find_sta_by_hw(&sdata->local->hw, addr); 891} 892EXPORT_SYMBOL(ieee80211_find_sta); 893 894/* powersave support code */ 895void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) 896{ 897 struct ieee80211_sub_if_data *sdata = sta->sdata; 898 struct ieee80211_local *local = sdata->local; 899 int sent, buffered; 900 901 drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta); 902 903 if (!skb_queue_empty(&sta->ps_tx_buf)) 904 sta_info_clear_tim_bit(sta); 905 906 /* Send all buffered frames to the station */ 907 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered); 908 buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf); 909 sent += buffered; 910 local->total_ps_buffered -= buffered; 911 912#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 913 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames " 914 "since STA not sleeping anymore\n", sdata->name, 915 sta->sta.addr, sta->sta.aid, sent - buffered, buffered); 916#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 917} 918 919void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta) 920{ 921 struct ieee80211_sub_if_data *sdata = sta->sdata; 922 struct ieee80211_local *local = sdata->local; 923 struct sk_buff *skb; 924 int no_pending_pkts; 925 926 skb = skb_dequeue(&sta->tx_filtered); 927 if (!skb) { 928 skb = skb_dequeue(&sta->ps_tx_buf); 929 if (skb) 930 local->total_ps_buffered--; 931 } 932 no_pending_pkts = skb_queue_empty(&sta->tx_filtered) && 933 skb_queue_empty(&sta->ps_tx_buf); 934 935 if (skb) { 936 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 937 struct ieee80211_hdr *hdr = 938 (struct ieee80211_hdr *) skb->data; 939 940 /* 941 * Tell TX path to send this frame even though the STA may 942 * still remain is PS mode after this frame exchange. 943 */ 944 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE; 945 946#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 947 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n", 948 sta->sta.addr, sta->sta.aid, 949 skb_queue_len(&sta->ps_tx_buf)); 950#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 951 952 /* Use MoreData flag to indicate whether there are more 953 * buffered frames for this STA */ 954 if (no_pending_pkts) 955 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 956 else 957 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 958 959 ieee80211_add_pending_skb(local, skb); 960 961 if (no_pending_pkts) 962 sta_info_clear_tim_bit(sta); 963#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 964 } else { 965 /* 966 * FIXME: This can be the result of a race condition between 967 * us expiring a frame and the station polling for it. 968 * Should we send it a null-func frame indicating we 969 * have nothing buffered for it? 970 */ 971 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even " 972 "though there are no buffered frames for it\n", 973 sdata->name, sta->sta.addr); 974#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 975 } 976} 977 978void ieee80211_sta_block_awake(struct ieee80211_hw *hw, 979 struct ieee80211_sta *pubsta, bool block) 980{ 981 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 982 983 if (block) 984 set_sta_flags(sta, WLAN_STA_PS_DRIVER); 985 else 986 ieee80211_queue_work(hw, &sta->drv_unblock_wk); 987} 988EXPORT_SYMBOL(ieee80211_sta_block_awake); 989