Commit | Line | Data |
---|---|---|
f0706e82 JB |
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> | |
0d174406 | 17 | #include <linux/timer.h> |
d0709a65 | 18 | #include <linux/rtnetlink.h> |
f0706e82 JB |
19 | |
20 | #include <net/mac80211.h> | |
21 | #include "ieee80211_i.h" | |
2c8dccc7 | 22 | #include "rate.h" |
f0706e82 | 23 | #include "sta_info.h" |
e9f207f0 | 24 | #include "debugfs_sta.h" |
ee385855 | 25 | #include "mesh.h" |
f0706e82 | 26 | |
d0709a65 JB |
27 | /** |
28 | * DOC: STA information lifetime rules | |
29 | * | |
30 | * STA info structures (&struct sta_info) are managed in a hash table | |
31 | * for faster lookup and a list for iteration. They are managed using | |
32 | * RCU, i.e. access to the list and hash table is protected by RCU. | |
33 | * | |
03e4497e JB |
34 | * Upon allocating a STA info structure with sta_info_alloc(), the caller owns |
35 | * that structure. It must then either destroy it using sta_info_destroy() | |
36 | * (which is pretty useless) or insert it into the hash table using | |
37 | * sta_info_insert() which demotes the reference from ownership to a regular | |
38 | * RCU-protected reference; if the function is called without protection by an | |
93e5deb1 JB |
39 | * RCU critical section the reference is instantly invalidated. Note that the |
40 | * caller may not do much with the STA info before inserting it, in particular, | |
41 | * it may not start any mesh peer link management or add encryption keys. | |
42 | * | |
43 | * When the insertion fails (sta_info_insert()) returns non-zero), the | |
44 | * structure will have been freed by sta_info_insert()! | |
d0709a65 JB |
45 | * |
46 | * Because there are debugfs entries for each station, and adding those | |
47 | * must be able to sleep, it is also possible to "pin" a station entry, | |
48 | * that means it can be removed from the hash table but not be freed. | |
93e5deb1 JB |
49 | * See the comment in __sta_info_unlink() for more information, this is |
50 | * an internal capability only. | |
d0709a65 JB |
51 | * |
52 | * In order to remove a STA info structure, the caller needs to first | |
dbbea671 | 53 | * unlink it (sta_info_unlink()) from the list and hash tables and |
3b96766f JB |
54 | * then destroy it; sta_info_destroy() will wait for an RCU grace period |
55 | * to elapse before actually freeing it. Due to the pinning and the | |
56 | * possibility of multiple callers trying to remove the same STA info at | |
57 | * the same time, sta_info_unlink() can clear the STA info pointer it is | |
58 | * passed to indicate that the STA info is owned by somebody else now. | |
d0709a65 | 59 | * |
dbbea671 | 60 | * If sta_info_unlink() did not clear the pointer then the caller owns |
d0709a65 | 61 | * the STA info structure now and is responsible of destroying it with |
3b96766f | 62 | * a call to sta_info_destroy(). |
d0709a65 JB |
63 | * |
64 | * In all other cases, there is no concept of ownership on a STA entry, | |
65 | * each structure is owned by the global hash table/list until it is | |
66 | * removed. All users of the structure need to be RCU protected so that | |
67 | * the structure won't be freed before they are done using it. | |
68 | */ | |
f0706e82 JB |
69 | |
70 | /* Caller must hold local->sta_lock */ | |
be8755e1 MW |
71 | static int sta_info_hash_del(struct ieee80211_local *local, |
72 | struct sta_info *sta) | |
f0706e82 JB |
73 | { |
74 | struct sta_info *s; | |
75 | ||
17741cdc | 76 | s = local->sta_hash[STA_HASH(sta->sta.addr)]; |
f0706e82 | 77 | if (!s) |
be8755e1 MW |
78 | return -ENOENT; |
79 | if (s == sta) { | |
17741cdc | 80 | rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], |
d0709a65 | 81 | s->hnext); |
be8755e1 | 82 | return 0; |
f0706e82 JB |
83 | } |
84 | ||
be8755e1 | 85 | while (s->hnext && s->hnext != sta) |
f0706e82 | 86 | s = s->hnext; |
be8755e1 | 87 | if (s->hnext) { |
d0709a65 | 88 | rcu_assign_pointer(s->hnext, sta->hnext); |
be8755e1 MW |
89 | return 0; |
90 | } | |
f0706e82 | 91 | |
be8755e1 | 92 | return -ENOENT; |
f0706e82 JB |
93 | } |
94 | ||
d0709a65 | 95 | /* protected by RCU */ |
4b7679a5 | 96 | struct sta_info *sta_info_get(struct ieee80211_local *local, const u8 *addr) |
f0706e82 JB |
97 | { |
98 | struct sta_info *sta; | |
99 | ||
d0709a65 | 100 | sta = rcu_dereference(local->sta_hash[STA_HASH(addr)]); |
f0706e82 | 101 | while (sta) { |
5cf12e8d | 102 | if (memcmp(sta->sta.addr, addr, ETH_ALEN) == 0) |
f0706e82 | 103 | break; |
d0709a65 | 104 | sta = rcu_dereference(sta->hnext); |
f0706e82 | 105 | } |
43ba7e95 JB |
106 | return sta; |
107 | } | |
108 | ||
ee385855 LCC |
109 | struct sta_info *sta_info_get_by_idx(struct ieee80211_local *local, int idx, |
110 | struct net_device *dev) | |
111 | { | |
112 | struct sta_info *sta; | |
113 | int i = 0; | |
114 | ||
d0709a65 | 115 | list_for_each_entry_rcu(sta, &local->sta_list, list) { |
2a8ca29a LCC |
116 | if (dev && dev != sta->sdata->dev) |
117 | continue; | |
ee385855 LCC |
118 | if (i < idx) { |
119 | ++i; | |
120 | continue; | |
ee385855 | 121 | } |
2a8ca29a | 122 | return sta; |
ee385855 | 123 | } |
ee385855 LCC |
124 | |
125 | return NULL; | |
126 | } | |
f0706e82 | 127 | |
93e5deb1 JB |
128 | /** |
129 | * __sta_info_free - internal STA free helper | |
130 | * | |
6ef307bc | 131 | * @local: pointer to the global information |
93e5deb1 JB |
132 | * @sta: STA info to free |
133 | * | |
134 | * This function must undo everything done by sta_info_alloc() | |
135 | * that may happen before sta_info_insert(). | |
136 | */ | |
137 | static void __sta_info_free(struct ieee80211_local *local, | |
138 | struct sta_info *sta) | |
139 | { | |
4b7679a5 | 140 | rate_control_free_sta(sta); |
93e5deb1 JB |
141 | rate_control_put(sta->rate_ctrl); |
142 | ||
143 | #ifdef CONFIG_MAC80211_VERBOSE_DEBUG | |
0c68ae26 JB |
144 | printk(KERN_DEBUG "%s: Destroyed STA %pM\n", |
145 | wiphy_name(local->hw.wiphy), sta->sta.addr); | |
93e5deb1 JB |
146 | #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ |
147 | ||
148 | kfree(sta); | |
149 | } | |
150 | ||
d0709a65 | 151 | void sta_info_destroy(struct sta_info *sta) |
f0706e82 | 152 | { |
97bff8ec | 153 | struct ieee80211_local *local; |
f0706e82 | 154 | struct sk_buff *skb; |
07db2183 | 155 | int i; |
73651ee6 | 156 | |
97bff8ec JB |
157 | might_sleep(); |
158 | ||
73651ee6 JB |
159 | if (!sta) |
160 | return; | |
f0706e82 | 161 | |
97bff8ec | 162 | local = sta->local; |
d0709a65 JB |
163 | |
164 | rate_control_remove_sta_debugfs(sta); | |
165 | ieee80211_sta_debugfs_remove(sta); | |
166 | ||
167 | #ifdef CONFIG_MAC80211_MESH | |
168 | if (ieee80211_vif_is_mesh(&sta->sdata->vif)) | |
169 | mesh_plink_deactivate(sta); | |
170 | #endif | |
171 | ||
3b96766f JB |
172 | /* |
173 | * We have only unlinked the key, and actually destroying it | |
174 | * may mean it is removed from hardware which requires that | |
175 | * the key->sta pointer is still valid, so flush the key todo | |
176 | * list here. | |
177 | * | |
178 | * ieee80211_key_todo() will synchronize_rcu() so after this | |
179 | * nothing can reference this sta struct any more. | |
180 | */ | |
181 | ieee80211_key_todo(); | |
d0709a65 JB |
182 | |
183 | #ifdef CONFIG_MAC80211_MESH | |
184 | if (ieee80211_vif_is_mesh(&sta->sdata->vif)) | |
185 | del_timer_sync(&sta->plink_timer); | |
186 | #endif | |
187 | ||
f0706e82 JB |
188 | while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) { |
189 | local->total_ps_buffered--; | |
190 | dev_kfree_skb_any(skb); | |
191 | } | |
d0709a65 JB |
192 | |
193 | while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL) | |
f0706e82 | 194 | dev_kfree_skb_any(skb); |
d0709a65 | 195 | |
fe3bf0f5 | 196 | for (i = 0; i < STA_TID_NUM; i++) { |
07346f81 | 197 | spin_lock_bh(&sta->lock); |
cee24a3e RR |
198 | if (sta->ampdu_mlme.tid_rx[i]) |
199 | del_timer_sync(&sta->ampdu_mlme.tid_rx[i]->session_timer); | |
cee24a3e RR |
200 | if (sta->ampdu_mlme.tid_tx[i]) |
201 | del_timer_sync(&sta->ampdu_mlme.tid_tx[i]->addba_resp_timer); | |
07346f81 | 202 | spin_unlock_bh(&sta->lock); |
fe3bf0f5 | 203 | } |
cee24a3e | 204 | |
93e5deb1 | 205 | __sta_info_free(local, sta); |
f0706e82 JB |
206 | } |
207 | ||
208 | ||
d0709a65 JB |
209 | /* Caller must hold local->sta_lock */ |
210 | static void sta_info_hash_add(struct ieee80211_local *local, | |
211 | struct sta_info *sta) | |
f0706e82 | 212 | { |
17741cdc JB |
213 | sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)]; |
214 | rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta); | |
f0706e82 | 215 | } |
f0706e82 | 216 | |
73651ee6 JB |
217 | struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, |
218 | u8 *addr, gfp_t gfp) | |
f0706e82 | 219 | { |
d0709a65 | 220 | struct ieee80211_local *local = sdata->local; |
f0706e82 | 221 | struct sta_info *sta; |
16c5f15c | 222 | int i; |
f0706e82 | 223 | |
17741cdc | 224 | sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp); |
f0706e82 | 225 | if (!sta) |
73651ee6 | 226 | return NULL; |
f0706e82 | 227 | |
07346f81 | 228 | spin_lock_init(&sta->lock); |
5a9f7b04 | 229 | spin_lock_init(&sta->flaglock); |
07346f81 | 230 | |
17741cdc | 231 | memcpy(sta->sta.addr, addr, ETH_ALEN); |
d0709a65 JB |
232 | sta->local = local; |
233 | sta->sdata = sdata; | |
f0706e82 JB |
234 | |
235 | sta->rate_ctrl = rate_control_get(local->rate_ctrl); | |
d0709a65 | 236 | sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl, |
4b7679a5 | 237 | &sta->sta, gfp); |
f0706e82 JB |
238 | if (!sta->rate_ctrl_priv) { |
239 | rate_control_put(sta->rate_ctrl); | |
f0706e82 | 240 | kfree(sta); |
73651ee6 | 241 | return NULL; |
f0706e82 JB |
242 | } |
243 | ||
16c5f15c RR |
244 | for (i = 0; i < STA_TID_NUM; i++) { |
245 | /* timer_to_tid must be initialized with identity mapping to | |
246 | * enable session_timer's data differentiation. refer to | |
247 | * sta_rx_agg_session_timer_expired for useage */ | |
248 | sta->timer_to_tid[i] = i; | |
fe3bf0f5 | 249 | /* tid to tx queue: initialize according to HW (0 is valid) */ |
e2530083 | 250 | sta->tid_to_tx_q[i] = ieee80211_num_queues(&local->hw); |
cee24a3e RR |
251 | /* rx */ |
252 | sta->ampdu_mlme.tid_state_rx[i] = HT_AGG_STATE_IDLE; | |
253 | sta->ampdu_mlme.tid_rx[i] = NULL; | |
254 | /* tx */ | |
255 | sta->ampdu_mlme.tid_state_tx[i] = HT_AGG_STATE_IDLE; | |
256 | sta->ampdu_mlme.tid_tx[i] = NULL; | |
257 | sta->ampdu_mlme.addba_req_num[i] = 0; | |
16c5f15c | 258 | } |
f0706e82 JB |
259 | skb_queue_head_init(&sta->ps_tx_buf); |
260 | skb_queue_head_init(&sta->tx_filtered); | |
73651ee6 JB |
261 | |
262 | #ifdef CONFIG_MAC80211_VERBOSE_DEBUG | |
0c68ae26 JB |
263 | printk(KERN_DEBUG "%s: Allocated STA %pM\n", |
264 | wiphy_name(local->hw.wiphy), sta->sta.addr); | |
73651ee6 JB |
265 | #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ |
266 | ||
03e4497e | 267 | #ifdef CONFIG_MAC80211_MESH |
b4e08ea1 | 268 | sta->plink_state = PLINK_LISTEN; |
03e4497e JB |
269 | init_timer(&sta->plink_timer); |
270 | #endif | |
271 | ||
73651ee6 JB |
272 | return sta; |
273 | } | |
274 | ||
275 | int sta_info_insert(struct sta_info *sta) | |
276 | { | |
277 | struct ieee80211_local *local = sta->local; | |
278 | struct ieee80211_sub_if_data *sdata = sta->sdata; | |
279 | unsigned long flags; | |
93e5deb1 | 280 | int err = 0; |
73651ee6 | 281 | |
03e4497e JB |
282 | /* |
283 | * Can't be a WARN_ON because it can be triggered through a race: | |
284 | * something inserts a STA (on one CPU) without holding the RTNL | |
285 | * and another CPU turns off the net device. | |
286 | */ | |
93e5deb1 JB |
287 | if (unlikely(!netif_running(sdata->dev))) { |
288 | err = -ENETDOWN; | |
289 | goto out_free; | |
290 | } | |
03e4497e | 291 | |
17741cdc | 292 | if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->dev->dev_addr) == 0 || |
c6a1fa12 | 293 | is_multicast_ether_addr(sta->sta.addr))) { |
93e5deb1 JB |
294 | err = -EINVAL; |
295 | goto out_free; | |
296 | } | |
44213b5e | 297 | |
d0709a65 | 298 | spin_lock_irqsave(&local->sta_lock, flags); |
43ba7e95 | 299 | /* check if STA exists already */ |
4b7679a5 | 300 | if (sta_info_get(local, sta->sta.addr)) { |
d0709a65 | 301 | spin_unlock_irqrestore(&local->sta_lock, flags); |
93e5deb1 JB |
302 | err = -EEXIST; |
303 | goto out_free; | |
43ba7e95 | 304 | } |
f0706e82 JB |
305 | list_add(&sta->list, &local->sta_list); |
306 | local->num_sta++; | |
307 | sta_info_hash_add(local, sta); | |
32bfd35d | 308 | |
d0709a65 JB |
309 | /* notify driver */ |
310 | if (local->ops->sta_notify) { | |
05c914fe | 311 | if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) |
3e122be0 JB |
312 | sdata = container_of(sdata->bss, |
313 | struct ieee80211_sub_if_data, | |
314 | u.ap); | |
32bfd35d JB |
315 | |
316 | local->ops->sta_notify(local_to_hw(local), &sdata->vif, | |
17741cdc | 317 | STA_NOTIFY_ADD, &sta->sta); |
32bfd35d | 318 | } |
d0709a65 | 319 | |
f0706e82 | 320 | #ifdef CONFIG_MAC80211_VERBOSE_DEBUG |
0c68ae26 JB |
321 | printk(KERN_DEBUG "%s: Inserted STA %pM\n", |
322 | wiphy_name(local->hw.wiphy), sta->sta.addr); | |
f0706e82 JB |
323 | #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ |
324 | ||
73651ee6 JB |
325 | spin_unlock_irqrestore(&local->sta_lock, flags); |
326 | ||
e9f207f0 | 327 | #ifdef CONFIG_MAC80211_DEBUGFS |
93e5deb1 JB |
328 | /* |
329 | * Debugfs entry adding might sleep, so schedule process | |
be8755e1 | 330 | * context task for adding entry for STAs that do not yet |
93e5deb1 JB |
331 | * have one. |
332 | * NOTE: due to auto-freeing semantics this may only be done | |
333 | * if the insertion is successful! | |
334 | */ | |
49ec6fa2 | 335 | schedule_work(&local->sta_debugfs_add); |
e9f207f0 JB |
336 | #endif |
337 | ||
73651ee6 JB |
338 | if (ieee80211_vif_is_mesh(&sdata->vif)) |
339 | mesh_accept_plinks_update(sdata); | |
340 | ||
341 | return 0; | |
93e5deb1 JB |
342 | out_free: |
343 | BUG_ON(!err); | |
344 | __sta_info_free(local, sta); | |
345 | return err; | |
f0706e82 JB |
346 | } |
347 | ||
004c872e JB |
348 | static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid) |
349 | { | |
350 | /* | |
351 | * This format has been mandated by the IEEE specifications, | |
352 | * so this line may not be changed to use the __set_bit() format. | |
353 | */ | |
354 | bss->tim[aid / 8] |= (1 << (aid % 8)); | |
355 | } | |
356 | ||
357 | static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid) | |
358 | { | |
359 | /* | |
360 | * This format has been mandated by the IEEE specifications, | |
361 | * so this line may not be changed to use the __clear_bit() format. | |
362 | */ | |
363 | bss->tim[aid / 8] &= ~(1 << (aid % 8)); | |
364 | } | |
365 | ||
366 | static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss, | |
367 | struct sta_info *sta) | |
368 | { | |
3e122be0 JB |
369 | BUG_ON(!bss); |
370 | ||
17741cdc | 371 | __bss_tim_set(bss, sta->sta.aid); |
3e122be0 | 372 | |
d0709a65 JB |
373 | if (sta->local->ops->set_tim) { |
374 | sta->local->tim_in_locked_section = true; | |
17741cdc JB |
375 | sta->local->ops->set_tim(local_to_hw(sta->local), |
376 | &sta->sta, true); | |
d0709a65 JB |
377 | sta->local->tim_in_locked_section = false; |
378 | } | |
004c872e JB |
379 | } |
380 | ||
381 | void sta_info_set_tim_bit(struct sta_info *sta) | |
382 | { | |
d0709a65 | 383 | unsigned long flags; |
004c872e | 384 | |
3e122be0 JB |
385 | BUG_ON(!sta->sdata->bss); |
386 | ||
d0709a65 JB |
387 | spin_lock_irqsave(&sta->local->sta_lock, flags); |
388 | __sta_info_set_tim_bit(sta->sdata->bss, sta); | |
389 | spin_unlock_irqrestore(&sta->local->sta_lock, flags); | |
004c872e JB |
390 | } |
391 | ||
392 | static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss, | |
393 | struct sta_info *sta) | |
394 | { | |
3e122be0 JB |
395 | BUG_ON(!bss); |
396 | ||
17741cdc | 397 | __bss_tim_clear(bss, sta->sta.aid); |
3e122be0 | 398 | |
d0709a65 JB |
399 | if (sta->local->ops->set_tim) { |
400 | sta->local->tim_in_locked_section = true; | |
17741cdc JB |
401 | sta->local->ops->set_tim(local_to_hw(sta->local), |
402 | &sta->sta, false); | |
d0709a65 JB |
403 | sta->local->tim_in_locked_section = false; |
404 | } | |
004c872e JB |
405 | } |
406 | ||
407 | void sta_info_clear_tim_bit(struct sta_info *sta) | |
408 | { | |
d0709a65 | 409 | unsigned long flags; |
004c872e | 410 | |
3e122be0 JB |
411 | BUG_ON(!sta->sdata->bss); |
412 | ||
d0709a65 JB |
413 | spin_lock_irqsave(&sta->local->sta_lock, flags); |
414 | __sta_info_clear_tim_bit(sta->sdata->bss, sta); | |
415 | spin_unlock_irqrestore(&sta->local->sta_lock, flags); | |
004c872e JB |
416 | } |
417 | ||
24723d1b | 418 | static void __sta_info_unlink(struct sta_info **sta) |
f0706e82 | 419 | { |
d0709a65 JB |
420 | struct ieee80211_local *local = (*sta)->local; |
421 | struct ieee80211_sub_if_data *sdata = (*sta)->sdata; | |
d0709a65 JB |
422 | /* |
423 | * pull caller's reference if we're already gone. | |
424 | */ | |
425 | if (sta_info_hash_del(local, *sta)) { | |
426 | *sta = NULL; | |
427 | return; | |
428 | } | |
be8755e1 | 429 | |
3b96766f JB |
430 | if ((*sta)->key) { |
431 | ieee80211_key_free((*sta)->key); | |
432 | WARN_ON((*sta)->key); | |
433 | } | |
434 | ||
7d1559f1 JB |
435 | list_del(&(*sta)->list); |
436 | ||
07346f81 | 437 | if (test_and_clear_sta_flags(*sta, WLAN_STA_PS)) { |
3e122be0 JB |
438 | BUG_ON(!sdata->bss); |
439 | ||
440 | atomic_dec(&sdata->bss->num_sta_ps); | |
7d1559f1 JB |
441 | __sta_info_clear_tim_bit(sdata->bss, *sta); |
442 | } | |
443 | ||
444 | local->num_sta--; | |
445 | ||
446 | if (local->ops->sta_notify) { | |
05c914fe | 447 | if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) |
3e122be0 JB |
448 | sdata = container_of(sdata->bss, |
449 | struct ieee80211_sub_if_data, | |
450 | u.ap); | |
7d1559f1 JB |
451 | |
452 | local->ops->sta_notify(local_to_hw(local), &sdata->vif, | |
17741cdc | 453 | STA_NOTIFY_REMOVE, &(*sta)->sta); |
7d1559f1 JB |
454 | } |
455 | ||
456 | if (ieee80211_vif_is_mesh(&sdata->vif)) { | |
457 | mesh_accept_plinks_update(sdata); | |
458 | #ifdef CONFIG_MAC80211_MESH | |
459 | del_timer(&(*sta)->plink_timer); | |
460 | #endif | |
461 | } | |
462 | ||
463 | #ifdef CONFIG_MAC80211_VERBOSE_DEBUG | |
0c68ae26 JB |
464 | printk(KERN_DEBUG "%s: Removed STA %pM\n", |
465 | wiphy_name(local->hw.wiphy), (*sta)->sta.addr); | |
7d1559f1 JB |
466 | #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */ |
467 | ||
d0709a65 | 468 | /* |
7d1559f1 | 469 | * Finally, pull caller's reference if the STA is pinned by the |
d0709a65 JB |
470 | * task that is adding the debugfs entries. In that case, we |
471 | * leave the STA "to be freed". | |
472 | * | |
473 | * The rules are not trivial, but not too complex either: | |
474 | * (1) pin_status is only modified under the sta_lock | |
49ec6fa2 JB |
475 | * (2) STAs may only be pinned under the RTNL so that |
476 | * sta_info_flush() is guaranteed to actually destroy | |
477 | * all STAs that are active for a given interface, this | |
478 | * is required for correctness because otherwise we | |
479 | * could notify a driver that an interface is going | |
480 | * away and only after that (!) notify it about a STA | |
481 | * on that interface going away. | |
482 | * (3) sta_info_debugfs_add_work() will set the status | |
d0709a65 JB |
483 | * to PINNED when it found an item that needs a new |
484 | * debugfs directory created. In that case, that item | |
485 | * must not be freed although all *RCU* users are done | |
486 | * with it. Hence, we tell the caller of _unlink() | |
487 | * that the item is already gone (as can happen when | |
488 | * two tasks try to unlink/destroy at the same time) | |
49ec6fa2 | 489 | * (4) We set the pin_status to DESTROY here when we |
d0709a65 | 490 | * find such an item. |
49ec6fa2 | 491 | * (5) sta_info_debugfs_add_work() will reset the pin_status |
d0709a65 JB |
492 | * from PINNED to NORMAL when it is done with the item, |
493 | * but will check for DESTROY before resetting it in | |
494 | * which case it will free the item. | |
495 | */ | |
496 | if ((*sta)->pin_status == STA_INFO_PIN_STAT_PINNED) { | |
497 | (*sta)->pin_status = STA_INFO_PIN_STAT_DESTROY; | |
498 | *sta = NULL; | |
499 | return; | |
500 | } | |
f0706e82 JB |
501 | } |
502 | ||
d0709a65 JB |
503 | void sta_info_unlink(struct sta_info **sta) |
504 | { | |
505 | struct ieee80211_local *local = (*sta)->local; | |
506 | unsigned long flags; | |
507 | ||
508 | spin_lock_irqsave(&local->sta_lock, flags); | |
509 | __sta_info_unlink(sta); | |
510 | spin_unlock_irqrestore(&local->sta_lock, flags); | |
511 | } | |
f0706e82 JB |
512 | |
513 | static inline int sta_info_buffer_expired(struct ieee80211_local *local, | |
514 | struct sta_info *sta, | |
515 | struct sk_buff *skb) | |
516 | { | |
e039fa4a | 517 | struct ieee80211_tx_info *info; |
f0706e82 JB |
518 | int timeout; |
519 | ||
520 | if (!skb) | |
521 | return 0; | |
522 | ||
e039fa4a | 523 | info = IEEE80211_SKB_CB(skb); |
f0706e82 JB |
524 | |
525 | /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */ | |
526 | timeout = (sta->listen_interval * local->hw.conf.beacon_int * 32 / | |
527 | 15625) * HZ; | |
528 | if (timeout < STA_TX_BUFFER_EXPIRE) | |
529 | timeout = STA_TX_BUFFER_EXPIRE; | |
e039fa4a | 530 | return time_after(jiffies, info->control.jiffies + timeout); |
f0706e82 JB |
531 | } |
532 | ||
533 | ||
534 | static void sta_info_cleanup_expire_buffered(struct ieee80211_local *local, | |
535 | struct sta_info *sta) | |
536 | { | |
537 | unsigned long flags; | |
538 | struct sk_buff *skb; | |
836341a7 | 539 | struct ieee80211_sub_if_data *sdata; |
f0706e82 JB |
540 | |
541 | if (skb_queue_empty(&sta->ps_tx_buf)) | |
542 | return; | |
543 | ||
544 | for (;;) { | |
545 | spin_lock_irqsave(&sta->ps_tx_buf.lock, flags); | |
546 | skb = skb_peek(&sta->ps_tx_buf); | |
836341a7 | 547 | if (sta_info_buffer_expired(local, sta, skb)) |
f0706e82 | 548 | skb = __skb_dequeue(&sta->ps_tx_buf); |
836341a7 | 549 | else |
f0706e82 JB |
550 | skb = NULL; |
551 | spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags); | |
552 | ||
836341a7 | 553 | if (!skb) |
f0706e82 | 554 | break; |
836341a7 | 555 | |
d0709a65 | 556 | sdata = sta->sdata; |
836341a7 | 557 | local->total_ps_buffered--; |
f4ea83dd | 558 | #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG |
0c68ae26 JB |
559 | printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n", |
560 | sta->sta.addr); | |
f4ea83dd | 561 | #endif |
836341a7 JB |
562 | dev_kfree_skb(skb); |
563 | ||
004c872e JB |
564 | if (skb_queue_empty(&sta->ps_tx_buf)) |
565 | sta_info_clear_tim_bit(sta); | |
f0706e82 JB |
566 | } |
567 | } | |
568 | ||
569 | ||
570 | static void sta_info_cleanup(unsigned long data) | |
571 | { | |
572 | struct ieee80211_local *local = (struct ieee80211_local *) data; | |
573 | struct sta_info *sta; | |
574 | ||
d0709a65 JB |
575 | rcu_read_lock(); |
576 | list_for_each_entry_rcu(sta, &local->sta_list, list) | |
f0706e82 | 577 | sta_info_cleanup_expire_buffered(local, sta); |
d0709a65 | 578 | rcu_read_unlock(); |
f0706e82 | 579 | |
0d174406 JB |
580 | local->sta_cleanup.expires = |
581 | round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); | |
f0706e82 JB |
582 | add_timer(&local->sta_cleanup); |
583 | } | |
584 | ||
e9f207f0 | 585 | #ifdef CONFIG_MAC80211_DEBUGFS |
4d6141c3 JS |
586 | /* |
587 | * See comment in __sta_info_unlink, | |
588 | * caller must hold local->sta_lock. | |
589 | */ | |
590 | static void __sta_info_pin(struct sta_info *sta) | |
591 | { | |
592 | WARN_ON(sta->pin_status != STA_INFO_PIN_STAT_NORMAL); | |
593 | sta->pin_status = STA_INFO_PIN_STAT_PINNED; | |
594 | } | |
595 | ||
596 | /* | |
597 | * See comment in __sta_info_unlink, returns sta if it | |
598 | * needs to be destroyed. | |
599 | */ | |
600 | static struct sta_info *__sta_info_unpin(struct sta_info *sta) | |
601 | { | |
602 | struct sta_info *ret = NULL; | |
603 | unsigned long flags; | |
604 | ||
605 | spin_lock_irqsave(&sta->local->sta_lock, flags); | |
606 | WARN_ON(sta->pin_status != STA_INFO_PIN_STAT_DESTROY && | |
607 | sta->pin_status != STA_INFO_PIN_STAT_PINNED); | |
608 | if (sta->pin_status == STA_INFO_PIN_STAT_DESTROY) | |
609 | ret = sta; | |
610 | sta->pin_status = STA_INFO_PIN_STAT_NORMAL; | |
611 | spin_unlock_irqrestore(&sta->local->sta_lock, flags); | |
612 | ||
613 | return ret; | |
614 | } | |
615 | ||
d0709a65 | 616 | static void sta_info_debugfs_add_work(struct work_struct *work) |
e9f207f0 JB |
617 | { |
618 | struct ieee80211_local *local = | |
619 | container_of(work, struct ieee80211_local, sta_debugfs_add); | |
620 | struct sta_info *sta, *tmp; | |
d0709a65 | 621 | unsigned long flags; |
e9f207f0 | 622 | |
49ec6fa2 JB |
623 | /* We need to keep the RTNL across the whole pinned status. */ |
624 | rtnl_lock(); | |
e9f207f0 JB |
625 | while (1) { |
626 | sta = NULL; | |
d0709a65 JB |
627 | |
628 | spin_lock_irqsave(&local->sta_lock, flags); | |
e9f207f0 | 629 | list_for_each_entry(tmp, &local->sta_list, list) { |
63044e9f JB |
630 | /* |
631 | * debugfs.add_has_run will be set by | |
632 | * ieee80211_sta_debugfs_add regardless | |
633 | * of what else it does. | |
634 | */ | |
635 | if (!tmp->debugfs.add_has_run) { | |
e9f207f0 | 636 | sta = tmp; |
d0709a65 | 637 | __sta_info_pin(sta); |
e9f207f0 JB |
638 | break; |
639 | } | |
640 | } | |
d0709a65 | 641 | spin_unlock_irqrestore(&local->sta_lock, flags); |
e9f207f0 JB |
642 | |
643 | if (!sta) | |
644 | break; | |
645 | ||
e9f207f0 JB |
646 | ieee80211_sta_debugfs_add(sta); |
647 | rate_control_add_sta_debugfs(sta); | |
d0709a65 JB |
648 | |
649 | sta = __sta_info_unpin(sta); | |
4f6fab47 | 650 | sta_info_destroy(sta); |
e9f207f0 | 651 | } |
49ec6fa2 | 652 | rtnl_unlock(); |
e9f207f0 JB |
653 | } |
654 | #endif | |
655 | ||
3b96766f | 656 | static void __ieee80211_run_pending_flush(struct ieee80211_local *local) |
dc6676b7 JB |
657 | { |
658 | struct sta_info *sta; | |
659 | unsigned long flags; | |
660 | ||
661 | ASSERT_RTNL(); | |
662 | ||
663 | spin_lock_irqsave(&local->sta_lock, flags); | |
664 | while (!list_empty(&local->sta_flush_list)) { | |
665 | sta = list_first_entry(&local->sta_flush_list, | |
666 | struct sta_info, list); | |
667 | list_del(&sta->list); | |
668 | spin_unlock_irqrestore(&local->sta_lock, flags); | |
669 | sta_info_destroy(sta); | |
670 | spin_lock_irqsave(&local->sta_lock, flags); | |
671 | } | |
672 | spin_unlock_irqrestore(&local->sta_lock, flags); | |
673 | } | |
674 | ||
675 | static void ieee80211_sta_flush_work(struct work_struct *work) | |
676 | { | |
677 | struct ieee80211_local *local = | |
678 | container_of(work, struct ieee80211_local, sta_flush_work); | |
679 | ||
680 | rtnl_lock(); | |
681 | __ieee80211_run_pending_flush(local); | |
682 | rtnl_unlock(); | |
683 | } | |
684 | ||
f0706e82 JB |
685 | void sta_info_init(struct ieee80211_local *local) |
686 | { | |
d0709a65 | 687 | spin_lock_init(&local->sta_lock); |
f0706e82 | 688 | INIT_LIST_HEAD(&local->sta_list); |
dc6676b7 JB |
689 | INIT_LIST_HEAD(&local->sta_flush_list); |
690 | INIT_WORK(&local->sta_flush_work, ieee80211_sta_flush_work); | |
f0706e82 | 691 | |
b24b8a24 PE |
692 | setup_timer(&local->sta_cleanup, sta_info_cleanup, |
693 | (unsigned long)local); | |
0d174406 JB |
694 | local->sta_cleanup.expires = |
695 | round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL); | |
e9f207f0 JB |
696 | |
697 | #ifdef CONFIG_MAC80211_DEBUGFS | |
d0709a65 | 698 | INIT_WORK(&local->sta_debugfs_add, sta_info_debugfs_add_work); |
e9f207f0 | 699 | #endif |
f0706e82 JB |
700 | } |
701 | ||
702 | int sta_info_start(struct ieee80211_local *local) | |
703 | { | |
704 | add_timer(&local->sta_cleanup); | |
705 | return 0; | |
706 | } | |
707 | ||
708 | void sta_info_stop(struct ieee80211_local *local) | |
709 | { | |
f0706e82 | 710 | del_timer(&local->sta_cleanup); |
dc6676b7 | 711 | cancel_work_sync(&local->sta_flush_work); |
49ec6fa2 JB |
712 | #ifdef CONFIG_MAC80211_DEBUGFS |
713 | /* | |
714 | * Make sure the debugfs adding work isn't pending after this | |
715 | * because we're about to be destroyed. It doesn't matter | |
716 | * whether it ran or not since we're going to flush all STAs | |
717 | * anyway. | |
718 | */ | |
719 | cancel_work_sync(&local->sta_debugfs_add); | |
720 | #endif | |
dc6676b7 JB |
721 | |
722 | rtnl_lock(); | |
be8755e1 | 723 | sta_info_flush(local, NULL); |
dc6676b7 JB |
724 | __ieee80211_run_pending_flush(local); |
725 | rtnl_unlock(); | |
f0706e82 JB |
726 | } |
727 | ||
f0706e82 JB |
728 | /** |
729 | * sta_info_flush - flush matching STA entries from the STA table | |
44213b5e JB |
730 | * |
731 | * Returns the number of removed STA entries. | |
732 | * | |
f0706e82 | 733 | * @local: local interface data |
d0709a65 | 734 | * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs |
f0706e82 | 735 | */ |
44213b5e | 736 | int sta_info_flush(struct ieee80211_local *local, |
d0709a65 | 737 | struct ieee80211_sub_if_data *sdata) |
f0706e82 JB |
738 | { |
739 | struct sta_info *sta, *tmp; | |
be8755e1 | 740 | LIST_HEAD(tmp_list); |
44213b5e | 741 | int ret = 0; |
d0709a65 | 742 | unsigned long flags; |
f0706e82 | 743 | |
d0709a65 | 744 | might_sleep(); |
dc6676b7 | 745 | ASSERT_RTNL(); |
be8755e1 | 746 | |
d0709a65 JB |
747 | spin_lock_irqsave(&local->sta_lock, flags); |
748 | list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { | |
749 | if (!sdata || sdata == sta->sdata) { | |
750 | __sta_info_unlink(&sta); | |
44213b5e | 751 | if (sta) { |
d0709a65 | 752 | list_add_tail(&sta->list, &tmp_list); |
44213b5e JB |
753 | ret++; |
754 | } | |
d0709a65 | 755 | } |
be8755e1 | 756 | } |
d0709a65 JB |
757 | spin_unlock_irqrestore(&local->sta_lock, flags); |
758 | ||
d0709a65 JB |
759 | list_for_each_entry_safe(sta, tmp, &tmp_list, list) |
760 | sta_info_destroy(sta); | |
44213b5e JB |
761 | |
762 | return ret; | |
f0706e82 | 763 | } |
dc6676b7 JB |
764 | |
765 | /** | |
766 | * sta_info_flush_delayed - flush matching STA entries from the STA table | |
767 | * | |
768 | * This function unlinks all stations for a given interface and queues | |
769 | * them for freeing. Note that the workqueue function scheduled here has | |
770 | * to run before any new keys can be added to the system to avoid set_key() | |
771 | * callback ordering issues. | |
772 | * | |
773 | * @sdata: the interface | |
774 | */ | |
775 | void sta_info_flush_delayed(struct ieee80211_sub_if_data *sdata) | |
776 | { | |
777 | struct ieee80211_local *local = sdata->local; | |
778 | struct sta_info *sta, *tmp; | |
779 | unsigned long flags; | |
780 | bool work = false; | |
781 | ||
782 | spin_lock_irqsave(&local->sta_lock, flags); | |
783 | list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { | |
784 | if (sdata == sta->sdata) { | |
785 | __sta_info_unlink(&sta); | |
786 | if (sta) { | |
787 | list_add_tail(&sta->list, | |
788 | &local->sta_flush_list); | |
789 | work = true; | |
790 | } | |
791 | } | |
792 | } | |
793 | if (work) | |
794 | schedule_work(&local->sta_flush_work); | |
795 | spin_unlock_irqrestore(&local->sta_lock, flags); | |
796 | } | |
24723d1b JB |
797 | |
798 | void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata, | |
799 | unsigned long exp_time) | |
800 | { | |
801 | struct ieee80211_local *local = sdata->local; | |
802 | struct sta_info *sta, *tmp; | |
803 | LIST_HEAD(tmp_list); | |
24723d1b JB |
804 | unsigned long flags; |
805 | ||
806 | spin_lock_irqsave(&local->sta_lock, flags); | |
807 | list_for_each_entry_safe(sta, tmp, &local->sta_list, list) | |
808 | if (time_after(jiffies, sta->last_rx + exp_time)) { | |
809 | #ifdef CONFIG_MAC80211_IBSS_DEBUG | |
0c68ae26 JB |
810 | printk(KERN_DEBUG "%s: expiring inactive STA %pM\n", |
811 | sdata->dev->name, sta->sta.addr); | |
24723d1b JB |
812 | #endif |
813 | __sta_info_unlink(&sta); | |
814 | if (sta) | |
815 | list_add(&sta->list, &tmp_list); | |
816 | } | |
817 | spin_unlock_irqrestore(&local->sta_lock, flags); | |
818 | ||
819 | list_for_each_entry_safe(sta, tmp, &tmp_list, list) | |
820 | sta_info_destroy(sta); | |
821 | } | |
17741cdc JB |
822 | |
823 | struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_hw *hw, | |
c6a1fa12 | 824 | const u8 *addr) |
17741cdc | 825 | { |
4b7679a5 | 826 | struct sta_info *sta = sta_info_get(hw_to_local(hw), addr); |
17741cdc JB |
827 | |
828 | if (!sta) | |
829 | return NULL; | |
830 | return &sta->sta; | |
831 | } | |
832 | EXPORT_SYMBOL(ieee80211_find_sta); |