package/mac80211/src/net/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 #include <linux/timer.h>
  18
  19 #include <net/mac80211.h>
  20 #include "ieee80211_i.h"
  21 #include "ieee80211_rate.h"
  22 #include "sta_info.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 int sta_info_hash_del(struct ieee80211_local *local,
  36                              struct sta_info *sta)
  37 {
  38         struct sta_info *s;
  39
  40         s = local->sta_hash[STA_HASH(sta->addr)];
  41         if (!s)
  42                 return -ENOENT;
  43         if (s == sta) {
  44                 local->sta_hash[STA_HASH(sta->addr)] = s->hnext;
  45                 return 0;
  46         }
  47
  48         while (s->hnext && s->hnext != sta)
  49                 s = s->hnext;
  50         if (s->hnext) {
  51                 s->hnext = sta->hnext;
  52                 return 0;
  53         }
  54
  55         return -ENOENT;
  56 }
  57
  58 struct sta_info *sta_info_get(struct ieee80211_local *local, u8 *addr)
  59 {
  60         struct sta_info *sta;
  61
  62         read_lock_bh(&local->sta_lock);
  63         sta = local->sta_hash[STA_HASH(addr)];
  64         while (sta) {
  65                 if (memcmp(sta->addr, addr, ETH_ALEN) == 0) {
  66                         __sta_info_get(sta);
  67                         break;
  68                 }
  69                 sta = sta->hnext;
  70         }
  71         read_unlock_bh(&local->sta_lock);
  72
  73         return sta;
  74 }
  75 EXPORT_SYMBOL(sta_info_get);
  76
  77
  78 static void sta_info_release(struct kref *kref)
  79 {
  80         struct sta_info *sta = container_of(kref, struct sta_info, kref);
  81         struct ieee80211_local *local = sta->local;
  82         struct sk_buff *skb;
  83         int i;
  84
  85         /* free sta structure; it has already been removed from
  86          * hash table etc. external structures. Make sure that all
  87          * buffered frames are release (one might have been added
  88          * after sta_info_free() was called). */
  89         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
  90                 local->total_ps_buffered--;
  91                 dev_kfree_skb_any(skb);
  92         }
  93         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
  94                 dev_kfree_skb_any(skb);
  95         }
  96         for (i = 0; i <  STA_TID_NUM; i++) {
  97                 del_timer_sync(&sta->ampdu_mlme.tid_rx[i].session_timer);
  98                 del_timer_sync(&sta->ampdu_mlme.tid_tx[i].addba_resp_timer);
  99         }
 100         rate_control_free_sta(sta->rate_ctrl, sta->rate_ctrl_priv);
 101         rate_control_put(sta->rate_ctrl);
 102         kfree(sta);
 103 }
 104
 105
 106 void sta_info_put(struct sta_info *sta)
 107 {
 108         kref_put(&sta->kref, sta_info_release);
 109 }
 110 EXPORT_SYMBOL(sta_info_put);
 111
 112
 113 struct sta_info * sta_info_add(struct ieee80211_local *local,
 114                                struct net_device *dev, u8 *addr, gfp_t gfp)
 115 {
 116         struct sta_info *sta;
 117         int i;
 118         DECLARE_MAC_BUF(mac);
 119
 120         sta = kzalloc(sizeof(*sta), gfp);
 121         if (!sta)
 122                 return NULL;
 123
 124         kref_init(&sta->kref);
 125
 126         sta->rate_ctrl = rate_control_get(local->rate_ctrl);
 127         sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, gfp);
 128         if (!sta->rate_ctrl_priv) {
 129                 rate_control_put(sta->rate_ctrl);
 130                 kfree(sta);
 131                 return NULL;
 132         }
 133
 134         memcpy(sta->addr, addr, ETH_ALEN);
 135         sta->local = local;
 136         sta->dev = dev;
 137         spin_lock_init(&sta->ampdu_mlme.ampdu_rx);
 138         spin_lock_init(&sta->ampdu_mlme.ampdu_tx);
 139         for (i = 0; i < STA_TID_NUM; i++) {
 140                 /* timer_to_tid must be initialized with identity mapping to
 141                  * enable session_timer's data differentiation. refer to
 142                  * sta_rx_agg_session_timer_expired for useage */
 143                 sta->timer_to_tid[i] = i;
 144                 /* tid to tx queue: initialize according to HW (0 is valid) */
 145                 sta->tid_to_tx_q[i] = local->hw.queues;
 146                 /* rx timers */
 147                 sta->ampdu_mlme.tid_rx[i].session_timer.function =
 148                         sta_rx_agg_session_timer_expired;
 149                 sta->ampdu_mlme.tid_rx[i].session_timer.data =
 150                         (unsigned long)&sta->timer_to_tid[i];
 151                 init_timer(&sta->ampdu_mlme.tid_rx[i].session_timer);
 152                 /* tx timers */
 153                 sta->ampdu_mlme.tid_tx[i].addba_resp_timer.function =
 154                         sta_addba_resp_timer_expired;
 155                 sta->ampdu_mlme.tid_tx[i].addba_resp_timer.data =
 156                         (unsigned long)&sta->timer_to_tid[i];
 157                 init_timer(&sta->ampdu_mlme.tid_tx[i].addba_resp_timer);
 158         }
 159         skb_queue_head_init(&sta->ps_tx_buf);
 160         skb_queue_head_init(&sta->tx_filtered);
 161         __sta_info_get(sta);    /* sta used by caller, decremented by
 162                                  * sta_info_put() */
 163         write_lock_bh(&local->sta_lock);
 164         list_add(&sta->list, &local->sta_list);
 165         local->num_sta++;
 166         sta_info_hash_add(local, sta);
 167         if (local->ops->sta_notify) {
 168                 struct ieee80211_sub_if_data *sdata;
 169
 170                 sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 171                 if (sdata->vif.type == IEEE80211_IF_TYPE_VLAN)
 172                         sdata = sdata->u.vlan.ap;
 173
 174                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
 175                                        STA_NOTIFY_ADD, addr);
 176         }
 177         write_unlock_bh(&local->sta_lock);
 178
 179 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 180         printk(KERN_DEBUG "%s: Added STA %s\n",
 181                wiphy_name(local->hw.wiphy), print_mac(mac, addr));
 182 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
 183
 184 #ifdef CONFIG_MAC80211_DEBUGFS
 185         /* debugfs entry adding might sleep, so schedule process
 186          * context task for adding entry for STAs that do not yet
 187          * have one. */
 188         queue_work(local->hw.workqueue, &local->sta_debugfs_add);
 189 #endif
 190
 191         return sta;
 192 }
 193
 194 /* Caller must hold local->sta_lock */
 195 void sta_info_remove(struct sta_info *sta)
 196 {
 197         struct ieee80211_local *local = sta->local;
 198         struct ieee80211_sub_if_data *sdata;
 199
 200         /* don't do anything if we've been removed already */
 201         if (sta_info_hash_del(local, sta))
 202                 return;
 203
 204         list_del(&sta->list);
 205         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 206         if (sta->flags & WLAN_STA_PS) {
 207                 sta->flags &= ~WLAN_STA_PS;
 208                 if (sdata->bss)
 209                         atomic_dec(&sdata->bss->num_sta_ps);
 210         }
 211         local->num_sta--;
 212         sta_info_remove_aid_ptr(sta);
 213
 214 }
 215
 216 void sta_info_free(struct sta_info *sta)
 217 {
 218         struct sk_buff *skb;
 219         struct ieee80211_local *local = sta->local;
 220         DECLARE_MAC_BUF(mac);
 221
 222         might_sleep();
 223
 224         write_lock_bh(&local->sta_lock);
 225         sta_info_remove(sta);
 226         write_unlock_bh(&local->sta_lock);
 227
 228         while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
 229                 local->total_ps_buffered--;
 230                 dev_kfree_skb(skb);
 231         }
 232         while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
 233                 dev_kfree_skb(skb);
 234         }
 235
 236 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
 237         printk(KERN_DEBUG "%s: Removed STA %s\n",
 238                wiphy_name(local->hw.wiphy), print_mac(mac, sta->addr));
 239 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
 240
 241         ieee80211_key_free(sta->key);
 242         sta->key = NULL;
 243
 244         if (local->ops->sta_notify) {
 245                 struct ieee80211_sub_if_data *sdata;
 246
 247                 sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 248
 249                 if (sdata->vif.type == IEEE80211_IF_TYPE_VLAN)
 250                         sdata = sdata->u.vlan.ap;
 251
 252                 local->ops->sta_notify(local_to_hw(local), &sdata->vif,
 253                                        STA_NOTIFY_REMOVE, sta->addr);
 254         }
 255
 256         rate_control_remove_sta_debugfs(sta);
 257         ieee80211_sta_debugfs_remove(sta);
 258
 259         sta_info_put(sta);
 260 }
 261
 262
 263 static inline int sta_info_buffer_expired(struct ieee80211_local *local,
 264                                           struct sta_info *sta,
 265                                           struct sk_buff *skb)
 266 {
 267         struct ieee80211_tx_packet_data *pkt_data;
 268         int timeout;
 269
 270         if (!skb)
 271                 return 0;
 272
 273         pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
 274
 275         /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
 276         timeout = (sta->listen_interval * local->hw.conf.beacon_int * 32 /
 277                    15625) * HZ;
 278         if (timeout < STA_TX_BUFFER_EXPIRE)
 279                 timeout = STA_TX_BUFFER_EXPIRE;
 280         return time_after(jiffies, pkt_data->jiffies + timeout);
 281 }
 282
 283
 284 static void sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
 285                                              struct sta_info *sta)
 286 {
 287         unsigned long flags;
 288         struct sk_buff *skb;
 289         DECLARE_MAC_BUF(mac);
 290
 291         if (skb_queue_empty(&sta->ps_tx_buf))
 292                 return;
 293
 294         for (;;) {
 295                 spin_lock_irqsave(&sta->ps_tx_buf.lock, flags);
 296                 skb = skb_peek(&sta->ps_tx_buf);
 297                 if (sta_info_buffer_expired(local, sta, skb)) {
 298                         skb = __skb_dequeue(&sta->ps_tx_buf);
 299                         if (skb_queue_empty(&sta->ps_tx_buf))
 300                                 sta->flags &= ~WLAN_STA_TIM;
 301                 } else
 302                         skb = NULL;
 303                 spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags);
 304
 305                 if (skb) {
 306                         local->total_ps_buffered--;
 307                         printk(KERN_DEBUG "Buffered frame expired (STA "
 308                                "%s)\n", print_mac(mac, sta->addr));
 309                         dev_kfree_skb(skb);
 310                 } else
 311                         break;
 312         }
 313 }
 314
 315
 316 static void sta_info_cleanup(unsigned long data)
 317 {
 318         struct ieee80211_local *local = (struct ieee80211_local *) data;
 319         struct sta_info *sta;
 320
 321         read_lock_bh(&local->sta_lock);
 322         list_for_each_entry(sta, &local->sta_list, list) {
 323                 __sta_info_get(sta);
 324                 sta_info_cleanup_expire_buffered(local, sta);
 325                 sta_info_put(sta);
 326         }
 327         read_unlock_bh(&local->sta_lock);
 328
 329         local->sta_cleanup.expires =
 330                 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
 331         add_timer(&local->sta_cleanup);
 332 }
 333
 334 #ifdef CONFIG_MAC80211_DEBUGFS
 335 static void sta_info_debugfs_add_task(struct work_struct *work)
 336 {
 337         struct ieee80211_local *local =
 338                 container_of(work, struct ieee80211_local, sta_debugfs_add);
 339         struct sta_info *sta, *tmp;
 340
 341         while (1) {
 342                 sta = NULL;
 343                 read_lock_bh(&local->sta_lock);
 344                 list_for_each_entry(tmp, &local->sta_list, list) {
 345                         if (!tmp->debugfs.dir) {
 346                                 sta = tmp;
 347                                 __sta_info_get(sta);
 348                                 break;
 349                         }
 350                 }
 351                 read_unlock_bh(&local->sta_lock);
 352
 353                 if (!sta)
 354                         break;
 355
 356                 ieee80211_sta_debugfs_add(sta);
 357                 rate_control_add_sta_debugfs(sta);
 358                 sta_info_put(sta);
 359         }
 360 }
 361 #endif
 362
 363 void sta_info_init(struct ieee80211_local *local)
 364 {
 365         rwlock_init(&local->sta_lock);
 366         INIT_LIST_HEAD(&local->sta_list);
 367
 368         init_timer(&local->sta_cleanup);
 369         local->sta_cleanup.expires =
 370                 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
 371         local->sta_cleanup.data = (unsigned long) local;
 372         local->sta_cleanup.function = sta_info_cleanup;
 373
 374 #ifdef CONFIG_MAC80211_DEBUGFS
 375         INIT_WORK(&local->sta_debugfs_add, sta_info_debugfs_add_task);
 376 #endif
 377 }
 378
 379 int sta_info_start(struct ieee80211_local *local)
 380 {
 381         add_timer(&local->sta_cleanup);
 382         return 0;
 383 }
 384
 385 void sta_info_stop(struct ieee80211_local *local)
 386 {
 387         del_timer(&local->sta_cleanup);
 388         sta_info_flush(local, NULL);
 389 }
 390
 391 void sta_info_remove_aid_ptr(struct sta_info *sta)
 392 {
 393         struct ieee80211_sub_if_data *sdata;
 394
 395         if (sta->aid <= 0)
 396                 return;
 397
 398         sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
 399
 400         if (sdata->local->ops->set_tim)
 401                 sdata->local->ops->set_tim(local_to_hw(sdata->local),
 402                                           sta->aid, 0);
 403         if (sdata->bss)
 404                 __bss_tim_clear(sdata->bss, sta->aid);
 405 }
 406
 407
 408 /**
 409  * sta_info_flush - flush matching STA entries from the STA table
 410  * @local: local interface data
 411  * @dev: matching rule for the net device (sta->dev) or %NULL to match all STAs
 412  */
 413 void sta_info_flush(struct ieee80211_local *local, struct net_device *dev)
 414 {
 415         struct sta_info *sta, *tmp;
 416         LIST_HEAD(tmp_list);
 417
 418         write_lock_bh(&local->sta_lock);
 419         list_for_each_entry_safe(sta, tmp, &local->sta_list, list)
 420                 if (!dev || dev == sta->dev) {
 421                         __sta_info_get(sta);
 422                         sta_info_remove(sta);
 423                         list_add_tail(&sta->list, &tmp_list);
 424                 }
 425         write_unlock_bh(&local->sta_lock);
 426
 427         list_for_each_entry_safe(sta, tmp, &tmp_list, list) {
 428                 sta_info_free(sta);
 429                 sta_info_put(sta);
 430         }
 431 }