xref: /openbmc/linux/net/mac80211/sta_info.c (revision ee3858551ae6d044578f598f8001db5f1a9fd52e)
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 #ifdef CONFIG_MAC80211_MESH
25 #include "mesh.h"
26 #endif
27 
28 /* Caller must hold local->sta_lock */
29 static void sta_info_hash_add(struct ieee80211_local *local,
30 			      struct sta_info *sta)
31 {
32 	sta->hnext = local->sta_hash[STA_HASH(sta->addr)];
33 	local->sta_hash[STA_HASH(sta->addr)] = sta;
34 }
35 
36 
37 /* Caller must hold local->sta_lock */
38 static int sta_info_hash_del(struct ieee80211_local *local,
39 			     struct sta_info *sta)
40 {
41 	struct sta_info *s;
42 
43 	s = local->sta_hash[STA_HASH(sta->addr)];
44 	if (!s)
45 		return -ENOENT;
46 	if (s == sta) {
47 		local->sta_hash[STA_HASH(sta->addr)] = s->hnext;
48 		return 0;
49 	}
50 
51 	while (s->hnext && s->hnext != sta)
52 		s = s->hnext;
53 	if (s->hnext) {
54 		s->hnext = sta->hnext;
55 		return 0;
56 	}
57 
58 	return -ENOENT;
59 }
60 
61 /* must hold local->sta_lock */
62 static struct sta_info *__sta_info_find(struct ieee80211_local *local,
63 					u8 *addr)
64 {
65 	struct sta_info *sta;
66 
67 	sta = local->sta_hash[STA_HASH(addr)];
68 	while (sta) {
69 		if (compare_ether_addr(sta->addr, addr) == 0)
70 			break;
71 		sta = sta->hnext;
72 	}
73 	return sta;
74 }
75 
76 struct sta_info *sta_info_get(struct ieee80211_local *local, u8 *addr)
77 {
78 	struct sta_info *sta;
79 
80 	read_lock_bh(&local->sta_lock);
81 	sta = __sta_info_find(local, addr);
82 	if (sta)
83 		__sta_info_get(sta);
84 	read_unlock_bh(&local->sta_lock);
85 
86 	return sta;
87 }
88 EXPORT_SYMBOL(sta_info_get);
89 
90 struct sta_info *sta_info_get_by_idx(struct ieee80211_local *local, int idx,
91 				     struct net_device *dev)
92 {
93 	struct sta_info *sta;
94 	int i = 0;
95 
96 	read_lock_bh(&local->sta_lock);
97 	list_for_each_entry(sta, &local->sta_list, list) {
98 		if (i < idx) {
99 			++i;
100 			continue;
101 		} else if (!dev || dev == sta->dev) {
102 			__sta_info_get(sta);
103 			read_unlock_bh(&local->sta_lock);
104 			return sta;
105 		}
106 	}
107 	read_unlock_bh(&local->sta_lock);
108 
109 	return NULL;
110 }
111 
112 static void sta_info_release(struct kref *kref)
113 {
114 	struct sta_info *sta = container_of(kref, struct sta_info, kref);
115 	struct ieee80211_local *local = sta->local;
116 	struct sk_buff *skb;
117 	int i;
118 
119 	/* free sta structure; it has already been removed from
120 	 * hash table etc. external structures. Make sure that all
121 	 * buffered frames are release (one might have been added
122 	 * after sta_info_free() was called). */
123 	while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
124 		local->total_ps_buffered--;
125 		dev_kfree_skb_any(skb);
126 	}
127 	while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
128 		dev_kfree_skb_any(skb);
129 	}
130 	for (i = 0; i <  STA_TID_NUM; i++) {
131 		del_timer_sync(&sta->ampdu_mlme.tid_rx[i].session_timer);
132 		del_timer_sync(&sta->ampdu_mlme.tid_tx[i].addba_resp_timer);
133 	}
134 	rate_control_free_sta(sta->rate_ctrl, sta->rate_ctrl_priv);
135 	rate_control_put(sta->rate_ctrl);
136 	kfree(sta);
137 }
138 
139 
140 void sta_info_put(struct sta_info *sta)
141 {
142 	kref_put(&sta->kref, sta_info_release);
143 }
144 EXPORT_SYMBOL(sta_info_put);
145 
146 
147 struct sta_info *sta_info_add(struct ieee80211_local *local,
148 			      struct net_device *dev, u8 *addr, gfp_t gfp)
149 {
150 	struct sta_info *sta;
151 	int i;
152 	DECLARE_MAC_BUF(mac);
153 
154 	sta = kzalloc(sizeof(*sta), gfp);
155 	if (!sta)
156 		return ERR_PTR(-ENOMEM);
157 
158 	kref_init(&sta->kref);
159 
160 	sta->rate_ctrl = rate_control_get(local->rate_ctrl);
161 	sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, gfp);
162 	if (!sta->rate_ctrl_priv) {
163 		rate_control_put(sta->rate_ctrl);
164 		kfree(sta);
165 		return ERR_PTR(-ENOMEM);
166 	}
167 
168 	memcpy(sta->addr, addr, ETH_ALEN);
169 	sta->local = local;
170 	sta->dev = dev;
171 	spin_lock_init(&sta->ampdu_mlme.ampdu_rx);
172 	spin_lock_init(&sta->ampdu_mlme.ampdu_tx);
173 	for (i = 0; i < STA_TID_NUM; i++) {
174 		/* timer_to_tid must be initialized with identity mapping to
175 		 * enable session_timer's data differentiation. refer to
176 		 * sta_rx_agg_session_timer_expired for useage */
177 		sta->timer_to_tid[i] = i;
178 		/* tid to tx queue: initialize according to HW (0 is valid) */
179 		sta->tid_to_tx_q[i] = local->hw.queues;
180 		/* rx timers */
181 		sta->ampdu_mlme.tid_rx[i].session_timer.function =
182 			sta_rx_agg_session_timer_expired;
183 		sta->ampdu_mlme.tid_rx[i].session_timer.data =
184 			(unsigned long)&sta->timer_to_tid[i];
185 		init_timer(&sta->ampdu_mlme.tid_rx[i].session_timer);
186 		/* tx timers */
187 		sta->ampdu_mlme.tid_tx[i].addba_resp_timer.function =
188 			sta_addba_resp_timer_expired;
189 		sta->ampdu_mlme.tid_tx[i].addba_resp_timer.data =
190 			(unsigned long)&sta->timer_to_tid[i];
191 		init_timer(&sta->ampdu_mlme.tid_tx[i].addba_resp_timer);
192 	}
193 	skb_queue_head_init(&sta->ps_tx_buf);
194 	skb_queue_head_init(&sta->tx_filtered);
195 	write_lock_bh(&local->sta_lock);
196 	/* mark sta as used (by caller) */
197 	__sta_info_get(sta);
198 	/* check if STA exists already */
199 	if (__sta_info_find(local, addr)) {
200 		write_unlock_bh(&local->sta_lock);
201 		sta_info_put(sta);
202 		return ERR_PTR(-EEXIST);
203 	}
204 	list_add(&sta->list, &local->sta_list);
205 	local->num_sta++;
206 	sta_info_hash_add(local, sta);
207 	if (local->ops->sta_notify) {
208 		struct ieee80211_sub_if_data *sdata;
209 
210 		sdata = IEEE80211_DEV_TO_SUB_IF(dev);
211 		if (sdata->vif.type == IEEE80211_IF_TYPE_VLAN)
212 			sdata = sdata->u.vlan.ap;
213 
214 		local->ops->sta_notify(local_to_hw(local), &sdata->vif,
215 				       STA_NOTIFY_ADD, addr);
216 	}
217 	write_unlock_bh(&local->sta_lock);
218 
219 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
220 	printk(KERN_DEBUG "%s: Added STA %s\n",
221 	       wiphy_name(local->hw.wiphy), print_mac(mac, addr));
222 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
223 
224 #ifdef CONFIG_MAC80211_DEBUGFS
225 	/* debugfs entry adding might sleep, so schedule process
226 	 * context task for adding entry for STAs that do not yet
227 	 * have one. */
228 	queue_work(local->hw.workqueue, &local->sta_debugfs_add);
229 #endif
230 
231 	return sta;
232 }
233 
234 static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid)
235 {
236 	/*
237 	 * This format has been mandated by the IEEE specifications,
238 	 * so this line may not be changed to use the __set_bit() format.
239 	 */
240 	bss->tim[aid / 8] |= (1 << (aid % 8));
241 }
242 
243 static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid)
244 {
245 	/*
246 	 * This format has been mandated by the IEEE specifications,
247 	 * so this line may not be changed to use the __clear_bit() format.
248 	 */
249 	bss->tim[aid / 8] &= ~(1 << (aid % 8));
250 }
251 
252 static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss,
253 				   struct sta_info *sta)
254 {
255 	if (bss)
256 		__bss_tim_set(bss, sta->aid);
257 	if (sta->local->ops->set_tim)
258 		sta->local->ops->set_tim(local_to_hw(sta->local), sta->aid, 1);
259 }
260 
261 void sta_info_set_tim_bit(struct sta_info *sta)
262 {
263 	struct ieee80211_sub_if_data *sdata;
264 
265 	sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
266 
267 	read_lock_bh(&sta->local->sta_lock);
268 	__sta_info_set_tim_bit(sdata->bss, sta);
269 	read_unlock_bh(&sta->local->sta_lock);
270 }
271 
272 static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss,
273 				     struct sta_info *sta)
274 {
275 	if (bss)
276 		__bss_tim_clear(bss, sta->aid);
277 	if (sta->local->ops->set_tim)
278 		sta->local->ops->set_tim(local_to_hw(sta->local), sta->aid, 0);
279 }
280 
281 void sta_info_clear_tim_bit(struct sta_info *sta)
282 {
283 	struct ieee80211_sub_if_data *sdata;
284 
285 	sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
286 
287 	read_lock_bh(&sta->local->sta_lock);
288 	__sta_info_clear_tim_bit(sdata->bss, sta);
289 	read_unlock_bh(&sta->local->sta_lock);
290 }
291 
292 /* Caller must hold local->sta_lock */
293 void sta_info_remove(struct sta_info *sta)
294 {
295 	struct ieee80211_local *local = sta->local;
296 	struct ieee80211_sub_if_data *sdata;
297 
298 	/* don't do anything if we've been removed already */
299 	if (sta_info_hash_del(local, sta))
300 		return;
301 
302 	list_del(&sta->list);
303 	sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
304 	if (sta->flags & WLAN_STA_PS) {
305 		sta->flags &= ~WLAN_STA_PS;
306 		if (sdata->bss)
307 			atomic_dec(&sdata->bss->num_sta_ps);
308 		__sta_info_clear_tim_bit(sdata->bss, sta);
309 	}
310 	local->num_sta--;
311 
312 #ifdef CONFIG_MAC80211_MESH
313 	if (sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT)
314 		mesh_accept_plinks_update(sdata->dev);
315 #endif
316 }
317 
318 void sta_info_free(struct sta_info *sta)
319 {
320 	struct sk_buff *skb;
321 	struct ieee80211_local *local = sta->local;
322 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
323 
324 	DECLARE_MAC_BUF(mac);
325 
326 	might_sleep();
327 
328 	write_lock_bh(&local->sta_lock);
329 	sta_info_remove(sta);
330 	write_unlock_bh(&local->sta_lock);
331 
332 #ifdef CONFIG_MAC80211_MESH
333 	if (sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT) {
334 		spin_lock_bh(&sta->plink_lock);
335 		mesh_plink_deactivate(sta);
336 		spin_unlock_bh(&sta->plink_lock);
337 	}
338 #endif
339 
340 	while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
341 		local->total_ps_buffered--;
342 		dev_kfree_skb(skb);
343 	}
344 	while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) {
345 		dev_kfree_skb(skb);
346 	}
347 
348 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
349 	printk(KERN_DEBUG "%s: Removed STA %s\n",
350 	       wiphy_name(local->hw.wiphy), print_mac(mac, sta->addr));
351 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
352 
353 	ieee80211_key_free(sta->key);
354 	WARN_ON(sta->key);
355 
356 	if (local->ops->sta_notify) {
357 
358 		if (sdata->vif.type == IEEE80211_IF_TYPE_VLAN)
359 			sdata = sdata->u.vlan.ap;
360 
361 		local->ops->sta_notify(local_to_hw(local), &sdata->vif,
362 				       STA_NOTIFY_REMOVE, sta->addr);
363 	}
364 
365 	rate_control_remove_sta_debugfs(sta);
366 	ieee80211_sta_debugfs_remove(sta);
367 
368 	sta_info_put(sta);
369 }
370 
371 
372 static inline int sta_info_buffer_expired(struct ieee80211_local *local,
373 					  struct sta_info *sta,
374 					  struct sk_buff *skb)
375 {
376 	struct ieee80211_tx_packet_data *pkt_data;
377 	int timeout;
378 
379 	if (!skb)
380 		return 0;
381 
382 	pkt_data = (struct ieee80211_tx_packet_data *) skb->cb;
383 
384 	/* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
385 	timeout = (sta->listen_interval * local->hw.conf.beacon_int * 32 /
386 		   15625) * HZ;
387 	if (timeout < STA_TX_BUFFER_EXPIRE)
388 		timeout = STA_TX_BUFFER_EXPIRE;
389 	return time_after(jiffies, pkt_data->jiffies + timeout);
390 }
391 
392 
393 static void sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
394 					     struct sta_info *sta)
395 {
396 	unsigned long flags;
397 	struct sk_buff *skb;
398 	struct ieee80211_sub_if_data *sdata;
399 	DECLARE_MAC_BUF(mac);
400 
401 	if (skb_queue_empty(&sta->ps_tx_buf))
402 		return;
403 
404 	for (;;) {
405 		spin_lock_irqsave(&sta->ps_tx_buf.lock, flags);
406 		skb = skb_peek(&sta->ps_tx_buf);
407 		if (sta_info_buffer_expired(local, sta, skb))
408 			skb = __skb_dequeue(&sta->ps_tx_buf);
409 		else
410 			skb = NULL;
411 		spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags);
412 
413 		if (!skb)
414 			break;
415 
416 		sdata = IEEE80211_DEV_TO_SUB_IF(sta->dev);
417 		local->total_ps_buffered--;
418 		printk(KERN_DEBUG "Buffered frame expired (STA "
419 		       "%s)\n", print_mac(mac, sta->addr));
420 		dev_kfree_skb(skb);
421 
422 		if (skb_queue_empty(&sta->ps_tx_buf))
423 			sta_info_clear_tim_bit(sta);
424 	}
425 }
426 
427 
428 static void sta_info_cleanup(unsigned long data)
429 {
430 	struct ieee80211_local *local = (struct ieee80211_local *) data;
431 	struct sta_info *sta;
432 
433 	read_lock_bh(&local->sta_lock);
434 	list_for_each_entry(sta, &local->sta_list, list) {
435 		__sta_info_get(sta);
436 		sta_info_cleanup_expire_buffered(local, sta);
437 		sta_info_put(sta);
438 	}
439 	read_unlock_bh(&local->sta_lock);
440 
441 	local->sta_cleanup.expires =
442 		round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
443 	add_timer(&local->sta_cleanup);
444 }
445 
446 #ifdef CONFIG_MAC80211_DEBUGFS
447 static void sta_info_debugfs_add_task(struct work_struct *work)
448 {
449 	struct ieee80211_local *local =
450 		container_of(work, struct ieee80211_local, sta_debugfs_add);
451 	struct sta_info *sta, *tmp;
452 
453 	while (1) {
454 		sta = NULL;
455 		read_lock_bh(&local->sta_lock);
456 		list_for_each_entry(tmp, &local->sta_list, list) {
457 			if (!tmp->debugfs.dir) {
458 				sta = tmp;
459 				__sta_info_get(sta);
460 				break;
461 			}
462 		}
463 		read_unlock_bh(&local->sta_lock);
464 
465 		if (!sta)
466 			break;
467 
468 		ieee80211_sta_debugfs_add(sta);
469 		rate_control_add_sta_debugfs(sta);
470 		sta_info_put(sta);
471 	}
472 }
473 #endif
474 
475 void sta_info_init(struct ieee80211_local *local)
476 {
477 	rwlock_init(&local->sta_lock);
478 	INIT_LIST_HEAD(&local->sta_list);
479 
480 	setup_timer(&local->sta_cleanup, sta_info_cleanup,
481 		    (unsigned long)local);
482 	local->sta_cleanup.expires =
483 		round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
484 
485 #ifdef CONFIG_MAC80211_DEBUGFS
486 	INIT_WORK(&local->sta_debugfs_add, sta_info_debugfs_add_task);
487 #endif
488 }
489 
490 int sta_info_start(struct ieee80211_local *local)
491 {
492 	add_timer(&local->sta_cleanup);
493 	return 0;
494 }
495 
496 void sta_info_stop(struct ieee80211_local *local)
497 {
498 	del_timer(&local->sta_cleanup);
499 	sta_info_flush(local, NULL);
500 }
501 
502 /**
503  * sta_info_flush - flush matching STA entries from the STA table
504  * @local: local interface data
505  * @dev: matching rule for the net device (sta->dev) or %NULL to match all STAs
506  */
507 void sta_info_flush(struct ieee80211_local *local, struct net_device *dev)
508 {
509 	struct sta_info *sta, *tmp;
510 	LIST_HEAD(tmp_list);
511 
512 	write_lock_bh(&local->sta_lock);
513 	list_for_each_entry_safe(sta, tmp, &local->sta_list, list)
514 		if (!dev || dev == sta->dev) {
515 			__sta_info_get(sta);
516 			sta_info_remove(sta);
517 			list_add_tail(&sta->list, &tmp_list);
518 		}
519 	write_unlock_bh(&local->sta_lock);
520 
521 	list_for_each_entry_safe(sta, tmp, &tmp_list, list) {
522 		sta_info_free(sta);
523 		sta_info_put(sta);
524 	}
525 }
526