package/mac80211/src/mac80211/sta_info.c

   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
  18 #include <net/mac80211.h>
  19 #include "ieee80211_i.h"
  20 #include "ieee80211_rate.h"
  21 #include "sta_info.h"
  22 #include "debugfs_key.h"
  23 #include "debugfs_sta.h"
  24
  25 /* Caller must hold local->sta_lock */
  26 static void sta_info_hash_add(struct ieee80211_local *local,
  27                               struct sta_info *sta)
  28 {
  29         sta->hnext = local->sta_hash[STA_HASH(sta->addr)];
  30         local->sta_hash[STA_HASH(sta->addr)] = sta;
  31 }
  32
  33
  34 /* Caller must hold local->sta_lock */
  35 static void sta_info_hash_del(struct ieee80211_local *local,
  36                               struct sta_info *sta, int dls)
  37 {
  38         struct sta_info *s;
  39
  40         s = local->sta_hash[STA_HASH(sta->addr)];
  41         if (!s)
  42                 return;
  43         if (memcmp(s->addr, sta->addr, ETH_ALEN) == 0) {
  44                 if (dls && !s->dls_sta)
  45                         return;
  46                 local->sta_hash[STA_HASH(sta->addr)] = s->hnext;
  47                 return;
  48         }
  49
  50         while (s->hnext && memcmp(s->hnext->addr, sta->addr, ETH_ALEN) != 0)
  51                 s = s->hnext;
  52         if (s->hnext) {
  53                 if (dls && !s->hnext->dls_sta)
  54                         return;
  55                 s->hnext = s->hnext->hnext;
  56         } else
  57                 printk(KERN_ERR "%s: could not remove STA " MAC_FMT " from "
  58                        "hash table\n", local->mdev->name, MAC_ARG(sta->addr));
  59 }
  60
  61 static inline void __sta_info_get(struct sta_info *sta)
  62 {
  63         kref_get(&sta->kref);
  64 }
  65
  66 struct sta_info *sta_info_get(struct ieee80211_local *local, u8 *addr)
  67 {
  68         struct sta_info *sta;
  69
  70         spin_lock_bh(&local->sta_lock);
  71         sta = local->sta_hash[STA_HASH(addr)];
  72         while (sta) {
  73                 if (memcmp(sta->addr, addr, ETH_ALEN) == 0) {
  74                         __sta_info_get(sta);
  75                         break;
  76                 }
  77                 sta = sta->hnext;
  78         }
  79         spin_unlock_bh(&local->sta_lock);
  80
  81         return sta;
  82 }
  83 EXPORT_SYMBOL(sta_info_get);
  84
  85 struct sta_info *dls_info_get(struct ieee80211_local *local, u8 *addr)
  86 {
  87         struct sta_info *sta;
  88
  89         spin_lock_bh(&local->sta_lock);
  90         sta = local->sta_hash[STA_HASH(addr)];
  91         while (sta) {
  92                 if (memcmp(sta->addr, addr, ETH_ALEN) == 0) {
  93                         if (!sta->dls_sta) {
  94                                 sta = NULL;
  95                                 break;
  96                         }
  97                         __sta_info_get(sta);
  98                         break;
  99                 }
 100                 sta = sta->hnext;
 101         }
 102         spin_unlock_bh(&local->sta_lock);
 103
 104         return sta;
 105 }
 106
 107 int sta_info_min_txrate_get(struct ieee80211_local *local)
 108 {
 109         struct sta_info *sta;
 110         struct ieee80211_hw_mode *mode;
 111         int min_txrate = 9999999;
 112         int i;
 113
 114         spin_lock_bh(&local->sta_lock);
 115         mode = local->oper_hw_mode;
 116         for (i = 0; i < STA_HASH_SIZE; i++) {
 117                 sta = local->sta_hash[i];
 118                 while (sta) {
 119                         if (sta->txrate < min_txrate)
 120                                 min_txrate = sta->txrate;
 121                         sta = sta->hnext;
 122                 }
 123         }
 124         spin_unlock_bh(&local->sta_lock);
 125         if (min_txrate == 9999999)
 126                 min_txrate = 0;
 127
 128         return mode->rates[min_txrate].rate;
 129 }
 130
 131
 132 static void sta_info_release(struct kref *kref)
 133 {
 134         struct sta_info *sta = container_of(kref, struct sta_info, kref);
 135         struct ieee80211_local *local = sta->local;
 136         struct sk_buff *skb;
 137
 138         /* free sta structure; it has already been removed from
 139          * hash table etc. external structures. Make sure that all
 140          * buffered frames are release (one might have been added
 141          * after sta_info_free() was called). */
 142         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 143                 local->total_ps_buffered--;
 144                 dev_kfree_skb_any(skb);
 145         }
 146         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 147                 dev_kfree_skb_any(skb);
 148         }
 149         rate_control_free_sta(sta->rate_ctrl, sta->rate_ctrl_priv);
 150         rate_control_put(sta->rate_ctrl);
 151         if (sta->key)
 152                 ieee80211_debugfs_key_sta_del(sta->key, sta);
 153         kfree(sta);
 154 }
 155
 156
 157 void sta_info_put(struct sta_info *sta)
 158 {
 159         kref_put(&sta->kref, sta_info_release);
 160 }
 161 EXPORT_SYMBOL(sta_info_put);
 162
 163
 164 struct sta_info * sta_info_add(struct ieee80211_local *local,
 165                                struct net_device *dev, u8 *addr, gfp_t gfp)
 166 {
 167         struct sta_info *sta;
 168
 169         sta = kzalloc(sizeof(*sta), gfp);
 170         if (!sta)
 171                 return NULL;
 172
 173         kref_init(&sta->kref);
 174
 175         sta->rate_ctrl = rate_control_get(local->rate_ctrl);
 176         sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, gfp);
 177         if (!sta->rate_ctrl_priv) {
 178                 rate_control_put(sta->rate_ctrl);
 179                 kref_put(&sta->kref, sta_info_release);
 180                 kfree(sta);
 181                 return NULL;
 182         }
 183
 184         memcpy(sta->addr, addr, ETH_ALEN);
 185         sta->local = local;
 186         sta->dev = dev;
 187         skb_queue_head_init(&sta->ps_tx_buf);
 188         skb_queue_head_init(&sta->tx_filtered);
 189         __sta_info_get(sta);    /* sta used by caller, decremented by
 190                                  * sta_info_put() */
 191         spin_lock_bh(&local->sta_lock);
 192         list_add(&sta->list, &local->sta_list);
 193         local->num_sta++;
 194         sta_info_hash_add(local, sta);
 195         spin_unlock_bh(&local->sta_lock);
 196         if (local->ops->sta_table_notification)
 197                 local->ops->sta_table_notification(local_to_hw(local),
 198                                                   local->num_sta);
 199         sta->key_idx_compression = HW_KEY_IDX_INVALID;
 200
 201 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 202         printk(KERN_DEBUG "%s: Added STA " MAC_FMT "\n",
 203                local->mdev->name, MAC_ARG(addr));
 204 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
 205
 206 #ifdef CONFIG_MAC80211_DEBUGFS
 207         if (!in_interrupt()) {
 208                 sta->debugfs_registered = 1;
 209                 ieee80211_sta_debugfs_add(sta);
 210                 rate_control_add_sta_debugfs(sta);
 211         } else {
 212                 /* debugfs entry adding might sleep, so schedule process
 213                  * context task for adding entry for STAs that do not yet
 214                  * have one. */
 215                 queue_work(local->hw.workqueue, &local->sta_debugfs_add);
 216         }
 217 #endif
 218
 219         return sta;
 220 }
 221
 222 static void finish_sta_info_free(struct ieee80211_local *local,
 223                                  struct sta_info *sta)
 224 {
 225 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 226         printk(KERN_DEBUG "%s: Removed STA " MAC_FMT "\n",
 227                local->mdev->name, MAC_ARG(sta->addr));
 228 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
 229
 230         if (sta->key) {
 231                 ieee80211_debugfs_key_remove(sta->key);
 232                 ieee80211_key_free(sta->key);
 233                 sta->key = NULL;
 234         }
 235
 236         rate_control_remove_sta_debugfs(sta);
 237         ieee80211_sta_debugfs_remove(sta);
 238
 239         sta_info_put(sta);
 240 }
 241
 242 static void sta_info_remove(struct sta_info *sta)
 243 {
 244         struct ieee80211_local *local = sta->local;
 245         struct ieee80211_sub_if_data *sdata;
 246
 247         sta_info_hash_del(local, sta, 0);
 248         list_del(&sta->list);
 249         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 250         if (sta->flags & WLAN_STA_PS) {
 251                 sta->flags &= ~WLAN_STA_PS;
 252                 if (sdata->bss)
 253                         atomic_dec(&sdata->bss->num_sta_ps);
 254         }
 255         local->num_sta--;
 256         sta_info_remove_aid_ptr(sta);
 257 }
 258
 259 void sta_info_free(struct sta_info *sta, int locked)
 260 {
 261         struct sk_buff *skb;
 262         struct ieee80211_local *local = sta->local;
 263
 264         if (!locked) {
 265                 spin_lock_bh(&local->sta_lock);
 266                 sta_info_remove(sta);
 267                 spin_unlock_bh(&local->sta_lock);
 268         } else {
 269                 sta_info_remove(sta);
 270         }
 271         if (local->ops->sta_table_notification)
 272                 local->ops->sta_table_notification(local_to_hw(local),
 273                                                   local->num_sta);
 274
 275         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 276                 local->total_ps_buffered--;
 277                 dev_kfree_skb_any(skb);
 278         }
 279         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 280                 dev_kfree_skb_any(skb);
 281         }
 282
 283         if (sta->key) {
 284                 if (local->ops->set_key) {
 285                         struct ieee80211_key_conf *key;
 286                         key = ieee80211_key_data2conf(local, sta->key);
 287                         if (key) {
 288                                 local->ops->set_key(local_to_hw(local),
 289                                                    DISABLE_KEY,
 290                                                    sta->addr, key, sta->aid);
 291                                 kfree(key);
 292                         }
 293                 }
 294         } else if (sta->key_idx_compression != HW_KEY_IDX_INVALID) {
 295                 struct ieee80211_key_conf conf;
 296                 memset(&conf, 0, sizeof(conf));
 297                 conf.hw_key_idx = sta->key_idx_compression;
 298                 conf.alg = ALG_NULL;
 299                 conf.flags |= IEEE80211_KEY_FORCE_SW_ENCRYPT;
 300                 local->ops->set_key(local_to_hw(local), DISABLE_KEY,
 301                                    sta->addr, &conf, sta->aid);
 302                 sta->key_idx_compression = HW_KEY_IDX_INVALID;
 303         }
 304
 305 #ifdef CONFIG_MAC80211_DEBUGFS
 306         if (in_atomic()) {
 307                 list_add(&sta->list, &local->deleted_sta_list);
 308                 queue_work(local->hw.workqueue, &local->sta_debugfs_add);
 309         } else
 310 #endif
 311                 finish_sta_info_free(local, sta);
 312 }
 313
 314
 315 static inline int sta_info_buffer_expired(struct ieee80211_local *local,
 316                                           struct sta_info *sta,
 317                                           struct sk_buff *skb)
 318 {
 319         struct ieee80211_tx_packet_data *pkt_data;
 320         int timeout;
 321
 322         if (!skb)
 323                 return 0;
 324
 325         pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 326
 327         /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
 328         timeout = (sta->listen_interval * local->hw.conf.beacon_int * 32 /
 329                    15625) * HZ;
 330         if (timeout < STA_TX_BUFFER_EXPIRE)
 331                 timeout = STA_TX_BUFFER_EXPIRE;
 332         return time_after(jiffies, pkt_data->jiffies + timeout);
 333 }
 334
 335
 336 static void sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
 337                                              struct sta_info *sta)
 338 {
 339         unsigned long flags;
 340         struct sk_buff *skb;
 341
 342         if (skb_queue_empty(&sta->ps_tx_buf))
 343                 return;
 344
 345         for (;;) {
 346                 spin_lock_irqsave(&sta->ps_tx_buf.lock, flags);
 347                 skb = skb_peek(&sta->ps_tx_buf);
 348                 if (sta_info_buffer_expired(local, sta, skb)) {
 349                         skb = __skb_dequeue(&sta->ps_tx_buf);
 350                         if (skb_queue_empty(&sta->ps_tx_buf))
 351                                 sta->flags &= ~WLAN_STA_TIM;
 352                 } else
 353                         skb = NULL;
 354                 spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags);
 355
 356                 if (skb) {
 357                         local->total_ps_buffered--;
 358                         printk(KERN_DEBUG "Buffered frame expired (STA "
 359                                MAC_FMT ")\n", MAC_ARG(sta->addr));
 360                         dev_kfree_skb(skb);
 361                 } else
 362                         break;
 363         }
 364 }
 365
 366
 367 static void sta_info_cleanup(unsigned long data)
 368 {
 369         struct ieee80211_local *local = (struct ieee80211_local *) data;
 370         struct sta_info *sta;
 371
 372         spin_lock_bh(&local->sta_lock);
 373         list_for_each_entry(sta, &local->sta_list, list) {
 374                 __sta_info_get(sta);
 375                 sta_info_cleanup_expire_buffered(local, sta);
 376                 sta_info_put(sta);
 377         }
 378         spin_unlock_bh(&local->sta_lock);
 379
 380         local->sta_cleanup.expires = jiffies + STA_INFO_CLEANUP_INTERVAL;
 381         add_timer(&local->sta_cleanup);
 382 }
 383
 384 #ifdef CONFIG_MAC80211_DEBUGFS
 385 static void sta_info_debugfs_add_task(struct work_struct *work)
 386 {
 387         struct ieee80211_local *local =
 388                 container_of(work, struct ieee80211_local, sta_debugfs_add);
 389         struct sta_info *sta, *tmp;
 390
 391         while (1) {
 392                 spin_lock_bh(&local->sta_lock);
 393                 if (!list_empty(&local->deleted_sta_list)) {
 394                         sta = list_entry(local->deleted_sta_list.next,
 395                                          struct sta_info, list);
 396                         list_del(local->deleted_sta_list.next);
 397                 } else
 398                         sta = NULL;
 399                 spin_unlock_bh(&local->sta_lock);
 400                 if (!sta)
 401                         break;
 402                 finish_sta_info_free(local, sta);
 403         }
 404
 405         while (1) {
 406                 sta = NULL;
 407                 spin_lock_bh(&local->sta_lock);
 408                 list_for_each_entry(tmp, &local->sta_list, list) {
 409                         if (!tmp->debugfs_registered) {
 410                                 sta = tmp;
 411                                 __sta_info_get(sta);
 412                                 break;
 413                         }
 414                 }
 415                 spin_unlock_bh(&local->sta_lock);
 416
 417                 if (!sta)
 418                         break;
 419
 420                 sta->debugfs_registered = 1;
 421                 ieee80211_sta_debugfs_add(sta);
 422                 rate_control_add_sta_debugfs(sta);
 423                 sta_info_put(sta);
 424         }
 425 }
 426 #endif
 427
 428 void sta_info_init(struct ieee80211_local *local)
 429 {
 430         spin_lock_init(&local->sta_lock);
 431         INIT_LIST_HEAD(&local->sta_list);
 432         INIT_LIST_HEAD(&local->deleted_sta_list);
 433
 434         init_timer(&local->sta_cleanup);
 435         local->sta_cleanup.expires = jiffies + STA_INFO_CLEANUP_INTERVAL;
 436         local->sta_cleanup.data = (unsigned long) local;
 437         local->sta_cleanup.function = sta_info_cleanup;
 438
 439 #ifdef CONFIG_MAC80211_DEBUGFS
 440         INIT_WORK(&local->sta_debugfs_add, sta_info_debugfs_add_task);
 441 #endif
 442 }
 443
 444 int sta_info_start(struct ieee80211_local *local)
 445 {
 446         add_timer(&local->sta_cleanup);
 447         return 0;
 448 }
 449
 450 void sta_info_stop(struct ieee80211_local *local)
 451 {
 452         struct sta_info *sta, *tmp;
 453
 454         del_timer(&local->sta_cleanup);
 455
 456         list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
 457                 /* sta_info_free must be called with 0 as the last
 458                  * parameter to ensure all debugfs sta entries are
 459                  * unregistered. We don't need locking at this
 460                  * point. */
 461                 sta_info_free(sta, 0);
 462         }
 463 }
 464
 465 void sta_info_remove_aid_ptr(struct sta_info *sta)
 466 {
 467         struct ieee80211_sub_if_data *sdata;
 468
 469         if (sta->aid <= 0)
 470                 return;
 471
 472         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 473
 474         if (sdata->local->ops->set_tim)
 475                 sdata->local->ops->set_tim(local_to_hw(sdata->local),
 476                                           sta->aid, 0);
 477         if (sdata->bss)
 478                 __bss_tim_clear(sdata->bss, sta->aid);
 479 }
 480
 481
 482 /**
 483  * sta_info_flush - flush matching STA entries from the STA table
 484  * @local: local interface data
 485  * @dev: matching rule for the net device (sta->dev) or %NULL to match all STAs
 486  */
 487 void sta_info_flush(struct ieee80211_local *local, struct net_device *dev)
 488 {
 489         struct sta_info *sta, *tmp;
 490
 491         spin_lock_bh(&local->sta_lock);
 492         list_for_each_entry_safe(sta, tmp, &local->sta_list, list)
 493                 if (!dev || dev == sta->dev)
 494                         sta_info_free(sta, 1);
 495         spin_unlock_bh(&local->sta_lock);
 496 }