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 */ 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 = 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 */ 90 struct 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 */ 116 struct 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 } 138 139 struct 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 */ 168 static 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 */ 184 static 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 } 190 191 static 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 } 208 209 static 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 } 225 226 struct 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 int i; 232 233 sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); 234 if (!sta) 235 return NULL; 236 237 spin_lock_init(&sta->lock); 238 spin_lock_init(&sta->flaglock); 239 INIT_WORK(&sta->drv_unblock_wk, sta_unblock); 240 INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work); 241 mutex_init(&sta->ampdu_mlme.mtx); 242 243 memcpy(sta->sta.addr, addr, ETH_ALEN); 244 sta->local = local; 245 sta->sdata = sdata; 246 247 ewma_init(&sta->avg_signal, 1024, 8); 248 249 if (sta_prepare_rate_control(local, sta, gfp)) { 250 kfree(sta); 251 return NULL; 252 } 253 254 for (i = 0; i < STA_TID_NUM; i++) { 255 /* 256 * timer_to_tid must be initialized with identity mapping 257 * to enable session_timer's data differentiation. See 258 * sta_rx_agg_session_timer_expired for usage. 259 */ 260 sta->timer_to_tid[i] = i; 261 } 262 skb_queue_head_init(&sta->ps_tx_buf); 263 skb_queue_head_init(&sta->tx_filtered); 264 265 for (i = 0; i < NUM_RX_DATA_QUEUES; i++) 266 sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX); 267 268 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 269 wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr); 270 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 271 272 #ifdef CONFIG_MAC80211_MESH 273 sta->plink_state = PLINK_LISTEN; 274 init_timer(&sta->plink_timer); 275 #endif 276 277 return sta; 278 } 279 280 static int sta_info_finish_insert(struct sta_info *sta, bool async) 281 { 282 struct ieee80211_local *local = sta->local; 283 struct ieee80211_sub_if_data *sdata = sta->sdata; 284 struct station_info sinfo; 285 unsigned long flags; 286 int err = 0; 287 288 lockdep_assert_held(&local->sta_mtx); 289 290 /* notify driver */ 291 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 292 sdata = container_of(sdata->bss, 293 struct ieee80211_sub_if_data, 294 u.ap); 295 err = drv_sta_add(local, sdata, &sta->sta); 296 if (err) { 297 if (!async) 298 return err; 299 printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to driver (%d)" 300 " - keeping it anyway.\n", 301 sdata->name, sta->sta.addr, err); 302 } else { 303 sta->uploaded = true; 304 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 305 if (async) 306 wiphy_debug(local->hw.wiphy, 307 "Finished adding IBSS STA %pM\n", 308 sta->sta.addr); 309 #endif 310 } 311 312 sdata = sta->sdata; 313 314 if (!async) { 315 local->num_sta++; 316 local->sta_generation++; 317 smp_mb(); 318 319 /* make the station visible */ 320 spin_lock_irqsave(&local->sta_lock, flags); 321 sta_info_hash_add(local, sta); 322 spin_unlock_irqrestore(&local->sta_lock, flags); 323 } 324 325 list_add(&sta->list, &local->sta_list); 326 327 ieee80211_sta_debugfs_add(sta); 328 rate_control_add_sta_debugfs(sta); 329 330 sinfo.filled = 0; 331 sinfo.generation = local->sta_generation; 332 cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL); 333 334 335 return 0; 336 } 337 338 static void sta_info_finish_pending(struct ieee80211_local *local) 339 { 340 struct sta_info *sta; 341 unsigned long flags; 342 343 spin_lock_irqsave(&local->sta_lock, flags); 344 while (!list_empty(&local->sta_pending_list)) { 345 sta = list_first_entry(&local->sta_pending_list, 346 struct sta_info, list); 347 list_del(&sta->list); 348 spin_unlock_irqrestore(&local->sta_lock, flags); 349 350 sta_info_finish_insert(sta, true); 351 352 spin_lock_irqsave(&local->sta_lock, flags); 353 } 354 spin_unlock_irqrestore(&local->sta_lock, flags); 355 } 356 357 static void sta_info_finish_work(struct work_struct *work) 358 { 359 struct ieee80211_local *local = 360 container_of(work, struct ieee80211_local, sta_finish_work); 361 362 mutex_lock(&local->sta_mtx); 363 sta_info_finish_pending(local); 364 mutex_unlock(&local->sta_mtx); 365 } 366 367 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU) 368 { 369 struct ieee80211_local *local = sta->local; 370 struct ieee80211_sub_if_data *sdata = sta->sdata; 371 unsigned long flags; 372 int err = 0; 373 374 /* 375 * Can't be a WARN_ON because it can be triggered through a race: 376 * something inserts a STA (on one CPU) without holding the RTNL 377 * and another CPU turns off the net device. 378 */ 379 if (unlikely(!ieee80211_sdata_running(sdata))) { 380 err = -ENETDOWN; 381 rcu_read_lock(); 382 goto out_free; 383 } 384 385 if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 || 386 is_multicast_ether_addr(sta->sta.addr))) { 387 err = -EINVAL; 388 rcu_read_lock(); 389 goto out_free; 390 } 391 392 /* 393 * In ad-hoc mode, we sometimes need to insert stations 394 * from tasklet context from the RX path. To avoid races, 395 * always do so in that case -- see the comment below. 396 */ 397 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) { 398 spin_lock_irqsave(&local->sta_lock, flags); 399 /* check if STA exists already */ 400 if (sta_info_get_bss(sdata, sta->sta.addr)) { 401 spin_unlock_irqrestore(&local->sta_lock, flags); 402 rcu_read_lock(); 403 err = -EEXIST; 404 goto out_free; 405 } 406 407 local->num_sta++; 408 local->sta_generation++; 409 smp_mb(); 410 sta_info_hash_add(local, sta); 411 412 list_add_tail(&sta->list, &local->sta_pending_list); 413 414 rcu_read_lock(); 415 spin_unlock_irqrestore(&local->sta_lock, flags); 416 417 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 418 wiphy_debug(local->hw.wiphy, "Added IBSS STA %pM\n", 419 sta->sta.addr); 420 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 421 422 ieee80211_queue_work(&local->hw, &local->sta_finish_work); 423 424 return 0; 425 } 426 427 /* 428 * On first glance, this will look racy, because the code 429 * below this point, which inserts a station with sleeping, 430 * unlocks the sta_lock between checking existence in the 431 * hash table and inserting into it. 432 * 433 * However, it is not racy against itself because it keeps 434 * the mutex locked. It still seems to race against the 435 * above code that atomically inserts the station... That, 436 * however, is not true because the above code can only 437 * be invoked for IBSS interfaces, and the below code will 438 * not be -- and the two do not race against each other as 439 * the hash table also keys off the interface. 440 */ 441 442 might_sleep(); 443 444 mutex_lock(&local->sta_mtx); 445 446 spin_lock_irqsave(&local->sta_lock, flags); 447 /* check if STA exists already */ 448 if (sta_info_get_bss(sdata, sta->sta.addr)) { 449 spin_unlock_irqrestore(&local->sta_lock, flags); 450 mutex_unlock(&local->sta_mtx); 451 rcu_read_lock(); 452 err = -EEXIST; 453 goto out_free; 454 } 455 456 spin_unlock_irqrestore(&local->sta_lock, flags); 457 458 err = sta_info_finish_insert(sta, false); 459 if (err) { 460 mutex_unlock(&local->sta_mtx); 461 rcu_read_lock(); 462 goto out_free; 463 } 464 465 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 466 wiphy_debug(local->hw.wiphy, "Inserted STA %pM\n", sta->sta.addr); 467 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 468 469 /* move reference to rcu-protected */ 470 rcu_read_lock(); 471 mutex_unlock(&local->sta_mtx); 472 473 if (ieee80211_vif_is_mesh(&sdata->vif)) 474 mesh_accept_plinks_update(sdata); 475 476 return 0; 477 out_free: 478 BUG_ON(!err); 479 __sta_info_free(local, sta); 480 return err; 481 } 482 483 int sta_info_insert(struct sta_info *sta) 484 { 485 int err = sta_info_insert_rcu(sta); 486 487 rcu_read_unlock(); 488 489 return err; 490 } 491 492 static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid) 493 { 494 /* 495 * This format has been mandated by the IEEE specifications, 496 * so this line may not be changed to use the __set_bit() format. 497 */ 498 bss->tim[aid / 8] |= (1 << (aid % 8)); 499 } 500 501 static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid) 502 { 503 /* 504 * This format has been mandated by the IEEE specifications, 505 * so this line may not be changed to use the __clear_bit() format. 506 */ 507 bss->tim[aid / 8] &= ~(1 << (aid % 8)); 508 } 509 510 static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss, 511 struct sta_info *sta) 512 { 513 BUG_ON(!bss); 514 515 __bss_tim_set(bss, sta->sta.aid); 516 517 if (sta->local->ops->set_tim) { 518 sta->local->tim_in_locked_section = true; 519 drv_set_tim(sta->local, &sta->sta, true); 520 sta->local->tim_in_locked_section = false; 521 } 522 } 523 524 void sta_info_set_tim_bit(struct sta_info *sta) 525 { 526 unsigned long flags; 527 528 BUG_ON(!sta->sdata->bss); 529 530 spin_lock_irqsave(&sta->local->sta_lock, flags); 531 __sta_info_set_tim_bit(sta->sdata->bss, sta); 532 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 533 } 534 535 static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss, 536 struct sta_info *sta) 537 { 538 BUG_ON(!bss); 539 540 __bss_tim_clear(bss, sta->sta.aid); 541 542 if (sta->local->ops->set_tim) { 543 sta->local->tim_in_locked_section = true; 544 drv_set_tim(sta->local, &sta->sta, false); 545 sta->local->tim_in_locked_section = false; 546 } 547 } 548 549 void sta_info_clear_tim_bit(struct sta_info *sta) 550 { 551 unsigned long flags; 552 553 BUG_ON(!sta->sdata->bss); 554 555 spin_lock_irqsave(&sta->local->sta_lock, flags); 556 __sta_info_clear_tim_bit(sta->sdata->bss, sta); 557 spin_unlock_irqrestore(&sta->local->sta_lock, flags); 558 } 559 560 static int sta_info_buffer_expired(struct sta_info *sta, 561 struct sk_buff *skb) 562 { 563 struct ieee80211_tx_info *info; 564 int timeout; 565 566 if (!skb) 567 return 0; 568 569 info = IEEE80211_SKB_CB(skb); 570 571 /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */ 572 timeout = (sta->listen_interval * 573 sta->sdata->vif.bss_conf.beacon_int * 574 32 / 15625) * HZ; 575 if (timeout < STA_TX_BUFFER_EXPIRE) 576 timeout = STA_TX_BUFFER_EXPIRE; 577 return time_after(jiffies, info->control.jiffies + timeout); 578 } 579 580 581 static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local, 582 struct sta_info *sta) 583 { 584 unsigned long flags; 585 struct sk_buff *skb; 586 struct ieee80211_sub_if_data *sdata; 587 588 if (skb_queue_empty(&sta->ps_tx_buf)) 589 return false; 590 591 for (;;) { 592 spin_lock_irqsave(&sta->ps_tx_buf.lock, flags); 593 skb = skb_peek(&sta->ps_tx_buf); 594 if (sta_info_buffer_expired(sta, skb)) 595 skb = __skb_dequeue(&sta->ps_tx_buf); 596 else 597 skb = NULL; 598 spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags); 599 600 if (!skb) 601 break; 602 603 sdata = sta->sdata; 604 local->total_ps_buffered--; 605 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG 606 printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n", 607 sta->sta.addr); 608 #endif 609 dev_kfree_skb(skb); 610 611 if (skb_queue_empty(&sta->ps_tx_buf)) 612 sta_info_clear_tim_bit(sta); 613 } 614 615 return true; 616 } 617 618 static int __must_check __sta_info_destroy(struct sta_info *sta) 619 { 620 struct ieee80211_local *local; 621 struct ieee80211_sub_if_data *sdata; 622 struct sk_buff *skb; 623 unsigned long flags; 624 int ret, i; 625 626 might_sleep(); 627 628 if (!sta) 629 return -ENOENT; 630 631 local = sta->local; 632 sdata = sta->sdata; 633 634 /* 635 * Before removing the station from the driver and 636 * rate control, it might still start new aggregation 637 * sessions -- block that to make sure the tear-down 638 * will be sufficient. 639 */ 640 set_sta_flags(sta, WLAN_STA_BLOCK_BA); 641 ieee80211_sta_tear_down_BA_sessions(sta, true); 642 643 spin_lock_irqsave(&local->sta_lock, flags); 644 ret = sta_info_hash_del(local, sta); 645 /* this might still be the pending list ... which is fine */ 646 if (!ret) 647 list_del(&sta->list); 648 spin_unlock_irqrestore(&local->sta_lock, flags); 649 if (ret) 650 return ret; 651 652 for (i = 0; i < NUM_DEFAULT_KEYS; i++) 653 ieee80211_key_free(local, sta->gtk[i]); 654 if (sta->ptk) 655 ieee80211_key_free(local, sta->ptk); 656 657 sta->dead = true; 658 659 if (test_and_clear_sta_flags(sta, 660 WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) { 661 BUG_ON(!sdata->bss); 662 663 atomic_dec(&sdata->bss->num_sta_ps); 664 __sta_info_clear_tim_bit(sdata->bss, sta); 665 } 666 667 local->num_sta--; 668 local->sta_generation++; 669 670 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 671 rcu_assign_pointer(sdata->u.vlan.sta, NULL); 672 673 if (sta->uploaded) { 674 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) 675 sdata = container_of(sdata->bss, 676 struct ieee80211_sub_if_data, 677 u.ap); 678 drv_sta_remove(local, sdata, &sta->sta); 679 sdata = sta->sdata; 680 } 681 682 /* 683 * At this point, after we wait for an RCU grace period, 684 * neither mac80211 nor the driver can reference this 685 * sta struct any more except by still existing timers 686 * associated with this station that we clean up below. 687 */ 688 synchronize_rcu(); 689 690 #ifdef CONFIG_MAC80211_MESH 691 if (ieee80211_vif_is_mesh(&sdata->vif)) 692 mesh_accept_plinks_update(sdata); 693 #endif 694 695 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG 696 wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr); 697 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ 698 cancel_work_sync(&sta->drv_unblock_wk); 699 700 rate_control_remove_sta_debugfs(sta); 701 ieee80211_sta_debugfs_remove(sta); 702 703 #ifdef CONFIG_MAC80211_MESH 704 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) { 705 mesh_plink_deactivate(sta); 706 del_timer_sync(&sta->plink_timer); 707 } 708 #endif 709 710 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { 711 local->total_ps_buffered--; 712 dev_kfree_skb_any(skb); 713 } 714 715 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) 716 dev_kfree_skb_any(skb); 717 718 __sta_info_free(local, sta); 719 720 return 0; 721 } 722 723 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr) 724 { 725 struct sta_info *sta; 726 int ret; 727 728 mutex_lock(&sdata->local->sta_mtx); 729 sta = sta_info_get(sdata, addr); 730 ret = __sta_info_destroy(sta); 731 mutex_unlock(&sdata->local->sta_mtx); 732 733 return ret; 734 } 735 736 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata, 737 const u8 *addr) 738 { 739 struct sta_info *sta; 740 int ret; 741 742 mutex_lock(&sdata->local->sta_mtx); 743 sta = sta_info_get_bss(sdata, addr); 744 ret = __sta_info_destroy(sta); 745 mutex_unlock(&sdata->local->sta_mtx); 746 747 return ret; 748 } 749 750 static void sta_info_cleanup(unsigned long data) 751 { 752 struct ieee80211_local *local = (struct ieee80211_local *) data; 753 struct sta_info *sta; 754 bool timer_needed = false; 755 756 rcu_read_lock(); 757 list_for_each_entry_rcu(sta, &local->sta_list, list) 758 if (sta_info_cleanup_expire_buffered(local, sta)) 759 timer_needed = true; 760 rcu_read_unlock(); 761 762 if (local->quiescing) 763 return; 764 765 if (!timer_needed) 766 return; 767 768 local->sta_cleanup.expires = 769 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); 770 add_timer(&local->sta_cleanup); 771 } 772 773 void sta_info_init(struct ieee80211_local *local) 774 { 775 spin_lock_init(&local->sta_lock); 776 mutex_init(&local->sta_mtx); 777 INIT_LIST_HEAD(&local->sta_list); 778 INIT_LIST_HEAD(&local->sta_pending_list); 779 INIT_WORK(&local->sta_finish_work, sta_info_finish_work); 780 781 setup_timer(&local->sta_cleanup, sta_info_cleanup, 782 (unsigned long)local); 783 local->sta_cleanup.expires = 784 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); 785 } 786 787 int sta_info_start(struct ieee80211_local *local) 788 { 789 add_timer(&local->sta_cleanup); 790 return 0; 791 } 792 793 void sta_info_stop(struct ieee80211_local *local) 794 { 795 del_timer(&local->sta_cleanup); 796 sta_info_flush(local, NULL); 797 } 798 799 /** 800 * sta_info_flush - flush matching STA entries from the STA table 801 * 802 * Returns the number of removed STA entries. 803 * 804 * @local: local interface data 805 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs 806 */ 807 int sta_info_flush(struct ieee80211_local *local, 808 struct ieee80211_sub_if_data *sdata) 809 { 810 struct sta_info *sta, *tmp; 811 int ret = 0; 812 813 might_sleep(); 814 815 mutex_lock(&local->sta_mtx); 816 817 sta_info_finish_pending(local); 818 819 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { 820 if (!sdata || sdata == sta->sdata) 821 WARN_ON(__sta_info_destroy(sta)); 822 } 823 mutex_unlock(&local->sta_mtx); 824 825 return ret; 826 } 827 828 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata, 829 unsigned long exp_time) 830 { 831 struct ieee80211_local *local = sdata->local; 832 struct sta_info *sta, *tmp; 833 834 mutex_lock(&local->sta_mtx); 835 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) 836 if (time_after(jiffies, sta->last_rx + exp_time)) { 837 #ifdef CONFIG_MAC80211_IBSS_DEBUG 838 printk(KERN_DEBUG "%s: expiring inactive STA %pM\n", 839 sdata->name, sta->sta.addr); 840 #endif 841 WARN_ON(__sta_info_destroy(sta)); 842 } 843 mutex_unlock(&local->sta_mtx); 844 } 845 846 struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw, 847 const u8 *addr, 848 const u8 *localaddr) 849 { 850 struct sta_info *sta, *nxt; 851 852 /* 853 * Just return a random station if localaddr is NULL 854 * ... first in list. 855 */ 856 for_each_sta_info(hw_to_local(hw), addr, sta, nxt) { 857 if (localaddr && 858 compare_ether_addr(sta->sdata->vif.addr, localaddr) != 0) 859 continue; 860 if (!sta->uploaded) 861 return NULL; 862 return &sta->sta; 863 } 864 865 return NULL; 866 } 867 EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr); 868 869 struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif, 870 const u8 *addr) 871 { 872 struct sta_info *sta; 873 874 if (!vif) 875 return NULL; 876 877 sta = sta_info_get_bss(vif_to_sdata(vif), addr); 878 if (!sta) 879 return NULL; 880 881 if (!sta->uploaded) 882 return NULL; 883 884 return &sta->sta; 885 } 886 EXPORT_SYMBOL(ieee80211_find_sta); 887 888 static void clear_sta_ps_flags(void *_sta) 889 { 890 struct sta_info *sta = _sta; 891 892 clear_sta_flags(sta, WLAN_STA_PS_DRIVER | WLAN_STA_PS_STA); 893 } 894 895 /* powersave support code */ 896 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta) 897 { 898 struct ieee80211_sub_if_data *sdata = sta->sdata; 899 struct ieee80211_local *local = sdata->local; 900 int sent, buffered; 901 902 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 } 920 921 void 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 } 979 980 void 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 } 992 EXPORT_SYMBOL(ieee80211_sta_block_awake); 993