sta_info.c revision 8cb231530f03961b55aa4e84e6ead5590bcde04d
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 && 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 clear_sta_flags(sta, WLAN_STA_PS_DRIVER); 204 ieee80211_sta_ps_deliver_poll_response(sta); 205 } else 206 clear_sta_flags(sta, WLAN_STA_PS_DRIVER); 207} 208 209static int sta_prepare_rate_control(struct ieee80211_local *local, 210 struct sta_info *sta, gfp_t gfp) 211{ 212 if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) 213 return 0; 214 215 sta->rate_ctrl = rate_control_get(local->rate_ctrl); 216 sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, 217 &sta->sta, gfp); 218 if (!sta->rate_ctrl_priv) { 219 rate_control_put(sta->rate_ctrl); 220 return -ENOMEM; 221 } 222 223 return 0; 224} 225 226struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, 227 u8 *addr, gfp_t gfp) 228{ 229 struct ieee80211_local *local = sdata->local; 230 struct sta_info *sta; 231 struct timespec uptime; 232 int i; 233 234 sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); 235 if (!sta) 236 return NULL; 237 238 spin_lock_init(&sta->lock); 239 spin_lock_init(&sta->flaglock); 240 INIT_WORK(&sta->drv_unblock_wk, sta_unblock); 241 INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work); 242 mutex_init(&sta->ampdu_mlme.mtx); 243 244 memcpy(sta->sta.addr, addr, ETH_ALEN); 245 sta->local = local; 246 sta->sdata = sdata; 247 sta->last_rx = jiffies; 248 249 do_posix_clock_monotonic_gettime(&uptime); 250 sta->last_connected = uptime.tv_sec; 251 ewma_init(&sta->avg_signal, 1024, 8); 252 253 if (sta_prepare_rate_control(local, sta, gfp)) { 254 kfree(sta); 255 return NULL; 256 } 257 258 for (i = 0; i < STA_TID_NUM; i++) { 259 /* 260 * timer_to_tid must be initialized with identity mapping 261 * to enable session_timer's data differentiation. See 262 * sta_rx_agg_session_timer_expired for usage. 263 */ 264 sta->timer_to_tid[i] = i; 265 } 266 skb_queue_head_init(&sta->ps_tx_buf); 267 skb_queue_head_init(&sta->tx_filtered); 268 269 for (i = 0; i < NUM_RX_DATA_QUEUES; i++) 270 sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX); 271 272#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 273 wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr); 274#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 275 276#ifdef CONFIG_MAC80211_MESH 277 sta->plink_state = PLINK_LISTEN; 278 init_timer(&sta->plink_timer); 279#endif 280 281 return sta; 282} 283 284static int sta_info_finish_insert(struct sta_info *sta, bool async) 285{ 286 struct ieee80211_local *local = sta->local; 287 struct ieee80211_sub_if_data *sdata = sta->sdata; 288 struct station_info sinfo; 289 unsigned long flags; 290 int err = 0; 291 292 lockdep_assert_held(&local->sta_mtx); 293 294 /* notify driver */ 295 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 296 sdata = container_of(sdata->bss, 297 struct ieee80211_sub_if_data, 298 u.ap); 299 err = drv_sta_add(local, sdata, &sta->sta); 300 if (err) { 301 if (!async) 302 return err; 303 printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to driver (%d)" 304 " - keeping it anyway.\n", 305 sdata->name, sta->sta.addr, err); 306 } else { 307 sta->uploaded = true; 308#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 309 if (async) 310 wiphy_debug(local->hw.wiphy, 311 "Finished adding IBSS STA %pM\n", 312 sta->sta.addr); 313#endif 314 } 315 316 sdata = sta->sdata; 317 318 if (!async) { 319 local->num_sta++; 320 local->sta_generation++; 321 smp_mb(); 322 323 /* make the station visible */ 324 spin_lock_irqsave(&local->sta_lock, flags); 325 sta_info_hash_add(local, sta); 326 spin_unlock_irqrestore(&local->sta_lock, flags); 327 } 328 329 list_add(&sta->list, &local->sta_list); 330 331 ieee80211_sta_debugfs_add(sta); 332 rate_control_add_sta_debugfs(sta); 333 334 sinfo.filled = 0; 335 sinfo.generation = local->sta_generation; 336 cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL); 337 338 339 return 0; 340} 341 342static void sta_info_finish_pending(struct ieee80211_local *local) 343{ 344 struct sta_info *sta; 345 unsigned long flags; 346 347 spin_lock_irqsave(&local->sta_lock, flags); 348 while (!list_empty(&local->sta_pending_list)) { 349 sta = list_first_entry(&local->sta_pending_list, 350 struct sta_info, list); 351 list_del(&sta->list); 352 spin_unlock_irqrestore(&local->sta_lock, flags); 353 354 sta_info_finish_insert(sta, true); 355 356 spin_lock_irqsave(&local->sta_lock, flags); 357 } 358 spin_unlock_irqrestore(&local->sta_lock, flags); 359} 360 361static void sta_info_finish_work(struct work_struct *work) 362{ 363 struct ieee80211_local *local = 364 container_of(work, struct ieee80211_local, sta_finish_work); 365 366 mutex_lock(&local->sta_mtx); 367 sta_info_finish_pending(local); 368 mutex_unlock(&local->sta_mtx); 369} 370 371int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU) 372{ 373 struct ieee80211_local *local = sta->local; 374 struct ieee80211_sub_if_data *sdata = sta->sdata; 375 unsigned long flags; 376 int err = 0; 377 378 /* 379 * Can't be a WARN_ON because it can be triggered through a race: 380 * something inserts a STA (on one CPU) without holding the RTNL 381 * and another CPU turns off the net device. 382 */ 383 if (unlikely(!ieee80211_sdata_running(sdata))) { 384 err = -ENETDOWN; 385 rcu_read_lock(); 386 goto out_free; 387 } 388 389 if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 || 390 is_multicast_ether_addr(sta->sta.addr))) { 391 err = -EINVAL; 392 rcu_read_lock(); 393 goto out_free; 394 } 395 396 /* 397 * In ad-hoc mode, we sometimes need to insert stations 398 * from tasklet context from the RX path. To avoid races, 399 * always do so in that case -- see the comment below. 400 */ 401 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 402 spin_lock_irqsave(&local->sta_lock, flags); 403 /* check if STA exists already */ 404 if (sta_info_get_bss(sdata, sta->sta.addr)) { 405 spin_unlock_irqrestore(&local->sta_lock, flags); 406 rcu_read_lock(); 407 err = -EEXIST; 408 goto out_free; 409 } 410 411 local->num_sta++; 412 local->sta_generation++; 413 smp_mb(); 414 sta_info_hash_add(local, sta); 415 416 list_add_tail(&sta->list, &local->sta_pending_list); 417 418 rcu_read_lock(); 419 spin_unlock_irqrestore(&local->sta_lock, flags); 420 421#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 422 wiphy_debug(local->hw.wiphy, "Added IBSS STA %pM\n", 423 sta->sta.addr); 424#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 425 426 ieee80211_queue_work(&local->hw, &local->sta_finish_work); 427 428 return 0; 429 } 430 431 /* 432 * On first glance, this will look racy, because the code 433 * below this point, which inserts a station with sleeping, 434 * unlocks the sta_lock between checking existence in the 435 * hash table and inserting into it. 436 * 437 * However, it is not racy against itself because it keeps 438 * the mutex locked. It still seems to race against the 439 * above code that atomically inserts the station... That, 440 * however, is not true because the above code can only 441 * be invoked for IBSS interfaces, and the below code will 442 * not be -- and the two do not race against each other as 443 * the hash table also keys off the interface. 444 */ 445 446 might_sleep(); 447 448 mutex_lock(&local->sta_mtx); 449 450 spin_lock_irqsave(&local->sta_lock, flags); 451 /* check if STA exists already */ 452 if (sta_info_get_bss(sdata, sta->sta.addr)) { 453 spin_unlock_irqrestore(&local->sta_lock, flags); 454 mutex_unlock(&local->sta_mtx); 455 rcu_read_lock(); 456 err = -EEXIST; 457 goto out_free; 458 } 459 460 spin_unlock_irqrestore(&local->sta_lock, flags); 461 462 err = sta_info_finish_insert(sta, false); 463 if (err) { 464 mutex_unlock(&local->sta_mtx); 465 rcu_read_lock(); 466 goto out_free; 467 } 468 469#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 470 wiphy_debug(local->hw.wiphy, "Inserted STA %pM\n", sta->sta.addr); 471#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 472 473 /* move reference to rcu-protected */ 474 rcu_read_lock(); 475 mutex_unlock(&local->sta_mtx); 476 477 if (ieee80211_vif_is_mesh(&sdata->vif)) 478 mesh_accept_plinks_update(sdata); 479 480 return 0; 481 out_free: 482 BUG_ON(!err); 483 __sta_info_free(local, sta); 484 return err; 485} 486 487int sta_info_insert(struct sta_info *sta) 488{ 489 int err = sta_info_insert_rcu(sta); 490 491 rcu_read_unlock(); 492 493 return err; 494} 495 496static inline void __bss_tim_set(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 __set_bit() format. 501 */ 502 bss->tim[aid / 8] |= (1 << (aid % 8)); 503} 504 505static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid) 506{ 507 /* 508 * This format has been mandated by the IEEE specifications, 509 * so this line may not be changed to use the __clear_bit() format. 510 */ 511 bss->tim[aid / 8] &= ~(1 << (aid % 8)); 512} 513 514static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss, 515 struct sta_info *sta) 516{ 517 BUG_ON(!bss); 518 519 __bss_tim_set(bss, sta->sta.aid); 520 521 if (sta->local->ops->set_tim) { 522 sta->local->tim_in_locked_section = true; 523 drv_set_tim(sta->local, &sta->sta, true); 524 sta->local->tim_in_locked_section = false; 525 } 526} 527 528void sta_info_set_tim_bit(struct sta_info *sta) 529{ 530 unsigned long flags; 531 532 BUG_ON(!sta->sdata->bss); 533 534 spin_lock_irqsave(&sta->local->sta_lock, flags); 535 __sta_info_set_tim_bit(sta->sdata->bss, sta); 536 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 537} 538 539static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss, 540 struct sta_info *sta) 541{ 542 BUG_ON(!bss); 543 544 __bss_tim_clear(bss, sta->sta.aid); 545 546 if (sta->local->ops->set_tim) { 547 sta->local->tim_in_locked_section = true; 548 drv_set_tim(sta->local, &sta->sta, false); 549 sta->local->tim_in_locked_section = false; 550 } 551} 552 553void sta_info_clear_tim_bit(struct sta_info *sta) 554{ 555 unsigned long flags; 556 557 BUG_ON(!sta->sdata->bss); 558 559 spin_lock_irqsave(&sta->local->sta_lock, flags); 560 __sta_info_clear_tim_bit(sta->sdata->bss, sta); 561 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 562} 563 564static int sta_info_buffer_expired(struct sta_info *sta, 565 struct sk_buff *skb) 566{ 567 struct ieee80211_tx_info *info; 568 int timeout; 569 570 if (!skb) 571 return 0; 572 573 info = IEEE80211_SKB_CB(skb); 574 575 /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */ 576 timeout = (sta->listen_interval * 577 sta->sdata->vif.bss_conf.beacon_int * 578 32 / 15625) * HZ; 579 if (timeout < STA_TX_BUFFER_EXPIRE) 580 timeout = STA_TX_BUFFER_EXPIRE; 581 return time_after(jiffies, info->control.jiffies + timeout); 582} 583 584 585static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local, 586 struct sta_info *sta) 587{ 588 unsigned long flags; 589 struct sk_buff *skb; 590 591 if (skb_queue_empty(&sta->ps_tx_buf)) 592 return false; 593 594 for (;;) { 595 spin_lock_irqsave(&sta->ps_tx_buf.lock, flags); 596 skb = skb_peek(&sta->ps_tx_buf); 597 if (sta_info_buffer_expired(sta, skb)) 598 skb = __skb_dequeue(&sta->ps_tx_buf); 599 else 600 skb = NULL; 601 spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags); 602 603 if (!skb) 604 break; 605 606 local->total_ps_buffered--; 607#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 608 printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n", 609 sta->sta.addr); 610#endif 611 dev_kfree_skb(skb); 612 613 if (skb_queue_empty(&sta->ps_tx_buf) && 614 !test_sta_flags(sta, WLAN_STA_PS_DRIVER_BUF)) 615 sta_info_clear_tim_bit(sta); 616 } 617 618 return true; 619} 620 621static int __must_check __sta_info_destroy(struct sta_info *sta) 622{ 623 struct ieee80211_local *local; 624 struct ieee80211_sub_if_data *sdata; 625 struct sk_buff *skb; 626 unsigned long flags; 627 int ret, i; 628 629 might_sleep(); 630 631 if (!sta) 632 return -ENOENT; 633 634 local = sta->local; 635 sdata = sta->sdata; 636 637 /* 638 * Before removing the station from the driver and 639 * rate control, it might still start new aggregation 640 * sessions -- block that to make sure the tear-down 641 * will be sufficient. 642 */ 643 set_sta_flags(sta, WLAN_STA_BLOCK_BA); 644 ieee80211_sta_tear_down_BA_sessions(sta, true); 645 646 spin_lock_irqsave(&local->sta_lock, flags); 647 ret = sta_info_hash_del(local, sta); 648 /* this might still be the pending list ... which is fine */ 649 if (!ret) 650 list_del(&sta->list); 651 spin_unlock_irqrestore(&local->sta_lock, flags); 652 if (ret) 653 return ret; 654 655 mutex_lock(&local->key_mtx); 656 for (i = 0; i < NUM_DEFAULT_KEYS; i++) 657 __ieee80211_key_free(sta->gtk[i]); 658 if (sta->ptk) 659 __ieee80211_key_free(sta->ptk); 660 mutex_unlock(&local->key_mtx); 661 662 sta->dead = true; 663 664 if (test_and_clear_sta_flags(sta, 665 WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) { 666 BUG_ON(!sdata->bss); 667 668 atomic_dec(&sdata->bss->num_sta_ps); 669 __sta_info_clear_tim_bit(sdata->bss, sta); 670 } 671 672 local->num_sta--; 673 local->sta_generation++; 674 675 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 676 rcu_assign_pointer(sdata->u.vlan.sta, NULL); 677 678 if (sta->uploaded) { 679 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 680 sdata = container_of(sdata->bss, 681 struct ieee80211_sub_if_data, 682 u.ap); 683 drv_sta_remove(local, sdata, &sta->sta); 684 sdata = sta->sdata; 685 } 686 687 /* 688 * At this point, after we wait for an RCU grace period, 689 * neither mac80211 nor the driver can reference this 690 * sta struct any more except by still existing timers 691 * associated with this station that we clean up below. 692 */ 693 synchronize_rcu(); 694 695#ifdef CONFIG_MAC80211_MESH 696 if (ieee80211_vif_is_mesh(&sdata->vif)) 697 mesh_accept_plinks_update(sdata); 698#endif 699 700#ifdef CONFIG_MAC80211_VERBOSE_DEBUG 701 wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr); 702#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 703 cancel_work_sync(&sta->drv_unblock_wk); 704 705 cfg80211_del_sta(sdata->dev, sta->sta.addr, GFP_KERNEL); 706 707 rate_control_remove_sta_debugfs(sta); 708 ieee80211_sta_debugfs_remove(sta); 709 710#ifdef CONFIG_MAC80211_MESH 711 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) { 712 mesh_plink_deactivate(sta); 713 del_timer_sync(&sta->plink_timer); 714 } 715#endif 716 717 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { 718 local->total_ps_buffered--; 719 dev_kfree_skb_any(skb); 720 } 721 722 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) 723 dev_kfree_skb_any(skb); 724 725 __sta_info_free(local, sta); 726 727 return 0; 728} 729 730int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr) 731{ 732 struct sta_info *sta; 733 int ret; 734 735 mutex_lock(&sdata->local->sta_mtx); 736 sta = sta_info_get(sdata, addr); 737 ret = __sta_info_destroy(sta); 738 mutex_unlock(&sdata->local->sta_mtx); 739 740 return ret; 741} 742 743int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata, 744 const u8 *addr) 745{ 746 struct sta_info *sta; 747 int ret; 748 749 mutex_lock(&sdata->local->sta_mtx); 750 sta = sta_info_get_bss(sdata, addr); 751 ret = __sta_info_destroy(sta); 752 mutex_unlock(&sdata->local->sta_mtx); 753 754 return ret; 755} 756 757static void sta_info_cleanup(unsigned long data) 758{ 759 struct ieee80211_local *local = (struct ieee80211_local *) data; 760 struct sta_info *sta; 761 bool timer_needed = false; 762 763 rcu_read_lock(); 764 list_for_each_entry_rcu(sta, &local->sta_list, list) 765 if (sta_info_cleanup_expire_buffered(local, sta)) 766 timer_needed = true; 767 rcu_read_unlock(); 768 769 if (local->quiescing) 770 return; 771 772 if (!timer_needed) 773 return; 774 775 mod_timer(&local->sta_cleanup, 776 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL)); 777} 778 779void sta_info_init(struct ieee80211_local *local) 780{ 781 spin_lock_init(&local->sta_lock); 782 mutex_init(&local->sta_mtx); 783 INIT_LIST_HEAD(&local->sta_list); 784 INIT_LIST_HEAD(&local->sta_pending_list); 785 INIT_WORK(&local->sta_finish_work, sta_info_finish_work); 786 787 setup_timer(&local->sta_cleanup, sta_info_cleanup, 788 (unsigned long)local); 789} 790 791void sta_info_stop(struct ieee80211_local *local) 792{ 793 del_timer(&local->sta_cleanup); 794 sta_info_flush(local, NULL); 795} 796 797/** 798 * sta_info_flush - flush matching STA entries from the STA table 799 * 800 * Returns the number of removed STA entries. 801 * 802 * @local: local interface data 803 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs 804 */ 805int sta_info_flush(struct ieee80211_local *local, 806 struct ieee80211_sub_if_data *sdata) 807{ 808 struct sta_info *sta, *tmp; 809 int ret = 0; 810 811 might_sleep(); 812 813 mutex_lock(&local->sta_mtx); 814 815 sta_info_finish_pending(local); 816 817 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 818 if (!sdata || sdata == sta->sdata) 819 WARN_ON(__sta_info_destroy(sta)); 820 } 821 mutex_unlock(&local->sta_mtx); 822 823 return ret; 824} 825 826void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata, 827 unsigned long exp_time) 828{ 829 struct ieee80211_local *local = sdata->local; 830 struct sta_info *sta, *tmp; 831 832 mutex_lock(&local->sta_mtx); 833 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) 834 if (time_after(jiffies, sta->last_rx + exp_time)) { 835#ifdef CONFIG_MAC80211_IBSS_DEBUG 836 printk(KERN_DEBUG "%s: expiring inactive STA %pM\n", 837 sdata->name, sta->sta.addr); 838#endif 839 WARN_ON(__sta_info_destroy(sta)); 840 } 841 mutex_unlock(&local->sta_mtx); 842} 843 844struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw, 845 const u8 *addr, 846 const u8 *localaddr) 847{ 848 struct sta_info *sta, *nxt; 849 850 /* 851 * Just return a random station if localaddr is NULL 852 * ... first in list. 853 */ 854 for_each_sta_info(hw_to_local(hw), addr, sta, nxt) { 855 if (localaddr && 856 compare_ether_addr(sta->sdata->vif.addr, localaddr) != 0) 857 continue; 858 if (!sta->uploaded) 859 return NULL; 860 return &sta->sta; 861 } 862 863 return NULL; 864} 865EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr); 866 867struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif, 868 const u8 *addr) 869{ 870 struct sta_info *sta; 871 872 if (!vif) 873 return NULL; 874 875 sta = sta_info_get_bss(vif_to_sdata(vif), addr); 876 if (!sta) 877 return NULL; 878 879 if (!sta->uploaded) 880 return NULL; 881 882 return &sta->sta; 883} 884EXPORT_SYMBOL(ieee80211_find_sta); 885 886static void clear_sta_ps_flags(void *_sta) 887{ 888 struct sta_info *sta = _sta; 889 890 clear_sta_flags(sta, WLAN_STA_PS_DRIVER | WLAN_STA_PS_STA); 891} 892 893/* powersave support code */ 894void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) 895{ 896 struct ieee80211_sub_if_data *sdata = sta->sdata; 897 struct ieee80211_local *local = sdata->local; 898 int sent, buffered; 899 900 clear_sta_flags(sta, WLAN_STA_PS_DRIVER_BUF); 901 if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS)) 902 drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta); 903 904 if (!skb_queue_empty(&sta->ps_tx_buf)) 905 sta_info_clear_tim_bit(sta); 906 907 /* Send all buffered frames to the station */ 908 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered); 909 buffered = ieee80211_add_pending_skbs_fn(local, &sta->ps_tx_buf, 910 clear_sta_ps_flags, sta); 911 sent += buffered; 912 local->total_ps_buffered -= buffered; 913 914#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 915 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames " 916 "since STA not sleeping anymore\n", sdata->name, 917 sta->sta.addr, sta->sta.aid, sent - buffered, buffered); 918#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 919} 920 921void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta) 922{ 923 struct ieee80211_sub_if_data *sdata = sta->sdata; 924 struct ieee80211_local *local = sdata->local; 925 struct sk_buff *skb; 926 int no_pending_pkts; 927 928 skb = skb_dequeue(&sta->tx_filtered); 929 if (!skb) { 930 skb = skb_dequeue(&sta->ps_tx_buf); 931 if (skb) 932 local->total_ps_buffered--; 933 } 934 no_pending_pkts = skb_queue_empty(&sta->tx_filtered) && 935 skb_queue_empty(&sta->ps_tx_buf); 936 937 if (skb) { 938 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 939 struct ieee80211_hdr *hdr = 940 (struct ieee80211_hdr *) skb->data; 941 942 /* 943 * Tell TX path to send this frame even though the STA may 944 * still remain is PS mode after this frame exchange. 945 */ 946 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE; 947 948#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 949 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n", 950 sta->sta.addr, sta->sta.aid, 951 skb_queue_len(&sta->ps_tx_buf)); 952#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 953 954 /* Use MoreData flag to indicate whether there are more 955 * buffered frames for this STA */ 956 if (no_pending_pkts) 957 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA); 958 else 959 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA); 960 961 ieee80211_add_pending_skb(local, skb); 962 963 if (no_pending_pkts) 964 sta_info_clear_tim_bit(sta); 965#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 966 } else { 967 /* 968 * FIXME: This can be the result of a race condition between 969 * us expiring a frame and the station polling for it. 970 * Should we send it a null-func frame indicating we 971 * have nothing buffered for it? 972 */ 973 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even " 974 "though there are no buffered frames for it\n", 975 sdata->name, sta->sta.addr); 976#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */ 977 } 978} 979 980void ieee80211_sta_block_awake(struct ieee80211_hw *hw, 981 struct ieee80211_sta *pubsta, bool block) 982{ 983 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 984 985 trace_api_sta_block_awake(sta->local, pubsta, block); 986 987 if (block) 988 set_sta_flags(sta, WLAN_STA_PS_DRIVER); 989 else if (test_sta_flags(sta, WLAN_STA_PS_DRIVER)) 990 ieee80211_queue_work(hw, &sta->drv_unblock_wk); 991} 992EXPORT_SYMBOL(ieee80211_sta_block_awake); 993 994void ieee80211_sta_set_tim(struct ieee80211_sta *pubsta) 995{ 996 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 997 998 set_sta_flags(sta, WLAN_STA_PS_DRIVER_BUF); 999 sta_info_set_tim_bit(sta); 1000} 1001EXPORT_SYMBOL(ieee80211_sta_set_tim); 1002