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1 | /* |
2 | * HT handling |
3 | * |
4 | * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> |
5 | * Copyright 2002-2005, Instant802 Networks, Inc. |
6 | * Copyright 2005-2006, Devicescape Software, Inc. |
7 | * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> |
8 | * Copyright 2007, Michael Wu <flamingice@sourmilk.net> |
9 | * Copyright 2007-2010, Intel Corporation |
10 | * |
11 | * This program is free software; you can redistribute it and/or modify |
12 | * it under the terms of the GNU General Public License version 2 as |
13 | * published by the Free Software Foundation. |
14 | */ |
15 | |
16 | #include <linux/ieee80211.h> |
17 | #include <linux/slab.h> |
18 | #include <linux/export.h> |
19 | #include <net/mac80211.h> |
20 | #include "ieee80211_i.h" |
21 | #include "driver-ops.h" |
22 | #include "wme.h" |
23 | |
24 | /** |
25 | * DOC: TX A-MPDU aggregation |
26 | * |
27 | * Aggregation on the TX side requires setting the hardware flag |
28 | * %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed |
29 | * packets with a flag indicating A-MPDU aggregation. The driver |
30 | * or device is responsible for actually aggregating the frames, |
31 | * as well as deciding how many and which to aggregate. |
32 | * |
33 | * When TX aggregation is started by some subsystem (usually the rate |
34 | * control algorithm would be appropriate) by calling the |
35 | * ieee80211_start_tx_ba_session() function, the driver will be |
36 | * notified via its @ampdu_action function, with the |
37 | * %IEEE80211_AMPDU_TX_START action. |
38 | * |
39 | * In response to that, the driver is later required to call the |
40 | * ieee80211_start_tx_ba_cb_irqsafe() function, which will really |
41 | * start the aggregation session after the peer has also responded. |
42 | * If the peer responds negatively, the session will be stopped |
43 | * again right away. Note that it is possible for the aggregation |
44 | * session to be stopped before the driver has indicated that it |
45 | * is done setting it up, in which case it must not indicate the |
46 | * setup completion. |
47 | * |
48 | * Also note that, since we also need to wait for a response from |
49 | * the peer, the driver is notified of the completion of the |
50 | * handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the |
51 | * @ampdu_action callback. |
52 | * |
53 | * Similarly, when the aggregation session is stopped by the peer |
54 | * or something calling ieee80211_stop_tx_ba_session(), the driver's |
55 | * @ampdu_action function will be called with the action |
56 | * %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail, |
57 | * and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe(). |
58 | * Note that the sta can get destroyed before the BA tear down is |
59 | * complete. |
60 | */ |
61 | |
62 | static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata, |
63 | const u8 *da, u16 tid, |
64 | u8 dialog_token, u16 start_seq_num, |
65 | u16 agg_size, u16 timeout) |
66 | { |
67 | struct ieee80211_local *local = sdata->local; |
68 | struct sk_buff *skb; |
69 | struct ieee80211_mgmt *mgmt; |
70 | u16 capab; |
71 | |
72 | skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); |
73 | |
74 | if (!skb) |
75 | return; |
76 | |
77 | skb_reserve(skb, local->hw.extra_tx_headroom); |
78 | mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24); |
79 | memset(mgmt, 0, 24); |
80 | memcpy(mgmt->da, da, ETH_ALEN); |
81 | memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); |
82 | if (sdata->vif.type == NL80211_IFTYPE_AP || |
83 | sdata->vif.type == NL80211_IFTYPE_AP_VLAN || |
84 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) |
85 | memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); |
86 | else if (sdata->vif.type == NL80211_IFTYPE_STATION) |
87 | memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); |
88 | else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) |
89 | memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); |
90 | |
91 | mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | |
92 | IEEE80211_STYPE_ACTION); |
93 | |
94 | skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req)); |
95 | |
96 | mgmt->u.action.category = WLAN_CATEGORY_BACK; |
97 | mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ; |
98 | |
99 | mgmt->u.action.u.addba_req.dialog_token = dialog_token; |
100 | capab = (u16)(1 << 1); /* bit 1 aggregation policy */ |
101 | capab |= (u16)(tid << 2); /* bit 5:2 TID number */ |
102 | capab |= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */ |
103 | |
104 | mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab); |
105 | |
106 | mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout); |
107 | mgmt->u.action.u.addba_req.start_seq_num = |
108 | cpu_to_le16(start_seq_num << 4); |
109 | |
110 | ieee80211_tx_skb(sdata, skb); |
111 | } |
112 | |
113 | void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn) |
114 | { |
115 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
116 | struct ieee80211_local *local = sdata->local; |
117 | struct sk_buff *skb; |
118 | struct ieee80211_bar *bar; |
119 | u16 bar_control = 0; |
120 | |
121 | skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom); |
122 | if (!skb) |
123 | return; |
124 | |
125 | skb_reserve(skb, local->hw.extra_tx_headroom); |
126 | bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar)); |
127 | memset(bar, 0, sizeof(*bar)); |
128 | bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | |
129 | IEEE80211_STYPE_BACK_REQ); |
130 | memcpy(bar->ra, ra, ETH_ALEN); |
131 | memcpy(bar->ta, sdata->vif.addr, ETH_ALEN); |
132 | bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL; |
133 | bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA; |
134 | bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT); |
135 | bar->control = cpu_to_le16(bar_control); |
136 | bar->start_seq_num = cpu_to_le16(ssn); |
137 | |
138 | IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT | |
139 | IEEE80211_TX_CTL_REQ_TX_STATUS; |
140 | ieee80211_tx_skb_tid(sdata, skb, tid); |
141 | } |
142 | EXPORT_SYMBOL(ieee80211_send_bar); |
143 | |
144 | void ieee80211_assign_tid_tx(struct sta_info *sta, int tid, |
145 | struct tid_ampdu_tx *tid_tx) |
146 | { |
147 | lockdep_assert_held(&sta->ampdu_mlme.mtx); |
148 | lockdep_assert_held(&sta->lock); |
149 | rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx); |
150 | } |
151 | |
152 | static inline int ieee80211_ac_from_tid(int tid) |
153 | { |
154 | return ieee802_1d_to_ac[tid & 7]; |
155 | } |
156 | |
157 | /* |
158 | * When multiple aggregation sessions on multiple stations |
159 | * are being created/destroyed simultaneously, we need to |
160 | * refcount the global queue stop caused by that in order |
161 | * to not get into a situation where one of the aggregation |
162 | * setup or teardown re-enables queues before the other is |
163 | * ready to handle that. |
164 | * |
165 | * These two functions take care of this issue by keeping |
166 | * a global "agg_queue_stop" refcount. |
167 | */ |
168 | static void __acquires(agg_queue) |
169 | ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid) |
170 | { |
171 | int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; |
172 | |
173 | if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1) |
174 | ieee80211_stop_queue_by_reason( |
175 | &sdata->local->hw, queue, |
176 | IEEE80211_QUEUE_STOP_REASON_AGGREGATION); |
177 | __acquire(agg_queue); |
178 | } |
179 | |
180 | static void __releases(agg_queue) |
181 | ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid) |
182 | { |
183 | int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; |
184 | |
185 | if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0) |
186 | ieee80211_wake_queue_by_reason( |
187 | &sdata->local->hw, queue, |
188 | IEEE80211_QUEUE_STOP_REASON_AGGREGATION); |
189 | __release(agg_queue); |
190 | } |
191 | |
192 | /* |
193 | * splice packets from the STA's pending to the local pending, |
194 | * requires a call to ieee80211_agg_splice_finish later |
195 | */ |
196 | static void __acquires(agg_queue) |
197 | ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata, |
198 | struct tid_ampdu_tx *tid_tx, u16 tid) |
199 | { |
200 | struct ieee80211_local *local = sdata->local; |
201 | int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; |
202 | unsigned long flags; |
203 | |
204 | ieee80211_stop_queue_agg(sdata, tid); |
205 | |
206 | if (WARN(!tid_tx, |
207 | "TID %d gone but expected when splicing aggregates from the pending queue\n", |
208 | tid)) |
209 | return; |
210 | |
211 | if (!skb_queue_empty(&tid_tx->pending)) { |
212 | spin_lock_irqsave(&local->queue_stop_reason_lock, flags); |
213 | /* copy over remaining packets */ |
214 | skb_queue_splice_tail_init(&tid_tx->pending, |
215 | &local->pending[queue]); |
216 | spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); |
217 | } |
218 | } |
219 | |
220 | static void __releases(agg_queue) |
221 | ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid) |
222 | { |
223 | ieee80211_wake_queue_agg(sdata, tid); |
224 | } |
225 | |
226 | static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid) |
227 | { |
228 | struct tid_ampdu_tx *tid_tx; |
229 | |
230 | lockdep_assert_held(&sta->ampdu_mlme.mtx); |
231 | lockdep_assert_held(&sta->lock); |
232 | |
233 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
234 | |
235 | /* |
236 | * When we get here, the TX path will not be lockless any more wrt. |
237 | * aggregation, since the OPERATIONAL bit has long been cleared. |
238 | * Thus it will block on getting the lock, if it occurs. So if we |
239 | * stop the queue now, we will not get any more packets, and any |
240 | * that might be being processed will wait for us here, thereby |
241 | * guaranteeing that no packets go to the tid_tx pending queue any |
242 | * more. |
243 | */ |
244 | |
245 | ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); |
246 | |
247 | /* future packets must not find the tid_tx struct any more */ |
248 | ieee80211_assign_tid_tx(sta, tid, NULL); |
249 | |
250 | ieee80211_agg_splice_finish(sta->sdata, tid); |
251 | |
252 | kfree_rcu(tid_tx, rcu_head); |
253 | } |
254 | |
255 | int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, |
256 | enum ieee80211_agg_stop_reason reason) |
257 | { |
258 | struct ieee80211_local *local = sta->local; |
259 | struct tid_ampdu_tx *tid_tx; |
260 | enum ieee80211_ampdu_mlme_action action; |
261 | int ret; |
262 | |
263 | lockdep_assert_held(&sta->ampdu_mlme.mtx); |
264 | |
265 | switch (reason) { |
266 | case AGG_STOP_DECLINED: |
267 | case AGG_STOP_LOCAL_REQUEST: |
268 | case AGG_STOP_PEER_REQUEST: |
269 | action = IEEE80211_AMPDU_TX_STOP_CONT; |
270 | break; |
271 | case AGG_STOP_DESTROY_STA: |
272 | action = IEEE80211_AMPDU_TX_STOP_FLUSH; |
273 | break; |
274 | default: |
275 | WARN_ON_ONCE(1); |
276 | return -EINVAL; |
277 | } |
278 | |
279 | spin_lock_bh(&sta->lock); |
280 | |
281 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
282 | if (!tid_tx) { |
283 | spin_unlock_bh(&sta->lock); |
284 | return -ENOENT; |
285 | } |
286 | |
287 | /* |
288 | * if we're already stopping ignore any new requests to stop |
289 | * unless we're destroying it in which case notify the driver |
290 | */ |
291 | if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { |
292 | spin_unlock_bh(&sta->lock); |
293 | if (reason != AGG_STOP_DESTROY_STA) |
294 | return -EALREADY; |
295 | ret = drv_ampdu_action(local, sta->sdata, |
296 | IEEE80211_AMPDU_TX_STOP_FLUSH_CONT, |
297 | &sta->sta, tid, NULL, 0); |
298 | WARN_ON_ONCE(ret); |
299 | return 0; |
300 | } |
301 | |
302 | if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) { |
303 | /* not even started yet! */ |
304 | ieee80211_assign_tid_tx(sta, tid, NULL); |
305 | spin_unlock_bh(&sta->lock); |
306 | kfree_rcu(tid_tx, rcu_head); |
307 | return 0; |
308 | } |
309 | |
310 | set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state); |
311 | |
312 | spin_unlock_bh(&sta->lock); |
313 | |
314 | ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n", |
315 | sta->sta.addr, tid); |
316 | |
317 | del_timer_sync(&tid_tx->addba_resp_timer); |
318 | del_timer_sync(&tid_tx->session_timer); |
319 | |
320 | /* |
321 | * After this packets are no longer handed right through |
322 | * to the driver but are put onto tid_tx->pending instead, |
323 | * with locking to ensure proper access. |
324 | */ |
325 | clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); |
326 | |
327 | /* |
328 | * There might be a few packets being processed right now (on |
329 | * another CPU) that have already gotten past the aggregation |
330 | * check when it was still OPERATIONAL and consequently have |
331 | * IEEE80211_TX_CTL_AMPDU set. In that case, this code might |
332 | * call into the driver at the same time or even before the |
333 | * TX paths calls into it, which could confuse the driver. |
334 | * |
335 | * Wait for all currently running TX paths to finish before |
336 | * telling the driver. New packets will not go through since |
337 | * the aggregation session is no longer OPERATIONAL. |
338 | */ |
339 | synchronize_net(); |
340 | |
341 | tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ? |
342 | WLAN_BACK_RECIPIENT : |
343 | WLAN_BACK_INITIATOR; |
344 | tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST; |
345 | |
346 | ret = drv_ampdu_action(local, sta->sdata, action, |
347 | &sta->sta, tid, NULL, 0); |
348 | |
349 | /* HW shall not deny going back to legacy */ |
350 | if (WARN_ON(ret)) { |
351 | /* |
352 | * We may have pending packets get stuck in this case... |
353 | * Not bothering with a workaround for now. |
354 | */ |
355 | } |
356 | |
357 | /* |
358 | * In the case of AGG_STOP_DESTROY_STA, the driver won't |
359 | * necessarily call ieee80211_stop_tx_ba_cb(), so this may |
360 | * seem like we can leave the tid_tx data pending forever. |
361 | * This is true, in a way, but "forever" is only until the |
362 | * station struct is actually destroyed. In the meantime, |
363 | * leaving it around ensures that we don't transmit packets |
364 | * to the driver on this TID which might confuse it. |
365 | */ |
366 | |
367 | return 0; |
368 | } |
369 | |
370 | /* |
371 | * After sending add Block Ack request we activated a timer until |
372 | * add Block Ack response will arrive from the recipient. |
373 | * If this timer expires sta_addba_resp_timer_expired will be executed. |
374 | */ |
375 | static void sta_addba_resp_timer_expired(unsigned long data) |
376 | { |
377 | /* not an elegant detour, but there is no choice as the timer passes |
378 | * only one argument, and both sta_info and TID are needed, so init |
379 | * flow in sta_info_create gives the TID as data, while the timer_to_id |
380 | * array gives the sta through container_of */ |
381 | u16 tid = *(u8 *)data; |
382 | struct sta_info *sta = container_of((void *)data, |
383 | struct sta_info, timer_to_tid[tid]); |
384 | struct tid_ampdu_tx *tid_tx; |
385 | |
386 | /* check if the TID waits for addBA response */ |
387 | rcu_read_lock(); |
388 | tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); |
389 | if (!tid_tx || |
390 | test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { |
391 | rcu_read_unlock(); |
392 | ht_dbg(sta->sdata, |
393 | "timer expired on %pM tid %d but we are not (or no longer) expecting addBA response there\n", |
394 | sta->sta.addr, tid); |
395 | return; |
396 | } |
397 | |
398 | ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n", |
399 | sta->sta.addr, tid); |
400 | |
401 | ieee80211_stop_tx_ba_session(&sta->sta, tid); |
402 | rcu_read_unlock(); |
403 | } |
404 | |
405 | void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid) |
406 | { |
407 | struct tid_ampdu_tx *tid_tx; |
408 | struct ieee80211_local *local = sta->local; |
409 | struct ieee80211_sub_if_data *sdata = sta->sdata; |
410 | u16 start_seq_num; |
411 | int ret; |
412 | |
413 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
414 | |
415 | /* |
416 | * Start queuing up packets for this aggregation session. |
417 | * We're going to release them once the driver is OK with |
418 | * that. |
419 | */ |
420 | clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); |
421 | |
422 | /* |
423 | * Make sure no packets are being processed. This ensures that |
424 | * we have a valid starting sequence number and that in-flight |
425 | * packets have been flushed out and no packets for this TID |
426 | * will go into the driver during the ampdu_action call. |
427 | */ |
428 | synchronize_net(); |
429 | |
430 | start_seq_num = sta->tid_seq[tid] >> 4; |
431 | |
432 | ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START, |
433 | &sta->sta, tid, &start_seq_num, 0); |
434 | if (ret) { |
435 | ht_dbg(sdata, |
436 | "BA request denied - HW unavailable for %pM tid %d\n", |
437 | sta->sta.addr, tid); |
438 | spin_lock_bh(&sta->lock); |
439 | ieee80211_agg_splice_packets(sdata, tid_tx, tid); |
440 | ieee80211_assign_tid_tx(sta, tid, NULL); |
441 | ieee80211_agg_splice_finish(sdata, tid); |
442 | spin_unlock_bh(&sta->lock); |
443 | |
444 | kfree_rcu(tid_tx, rcu_head); |
445 | return; |
446 | } |
447 | |
448 | /* activate the timer for the recipient's addBA response */ |
449 | mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL); |
450 | ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n", |
451 | sta->sta.addr, tid); |
452 | |
453 | spin_lock_bh(&sta->lock); |
454 | sta->ampdu_mlme.last_addba_req_time[tid] = jiffies; |
455 | sta->ampdu_mlme.addba_req_num[tid]++; |
456 | spin_unlock_bh(&sta->lock); |
457 | |
458 | /* send AddBA request */ |
459 | ieee80211_send_addba_request(sdata, sta->sta.addr, tid, |
460 | tid_tx->dialog_token, start_seq_num, |
461 | local->hw.max_tx_aggregation_subframes, |
462 | tid_tx->timeout); |
463 | } |
464 | |
465 | /* |
466 | * After accepting the AddBA Response we activated a timer, |
467 | * resetting it after each frame that we send. |
468 | */ |
469 | static void sta_tx_agg_session_timer_expired(unsigned long data) |
470 | { |
471 | /* not an elegant detour, but there is no choice as the timer passes |
472 | * only one argument, and various sta_info are needed here, so init |
473 | * flow in sta_info_create gives the TID as data, while the timer_to_id |
474 | * array gives the sta through container_of */ |
475 | u8 *ptid = (u8 *)data; |
476 | u8 *timer_to_id = ptid - *ptid; |
477 | struct sta_info *sta = container_of(timer_to_id, struct sta_info, |
478 | timer_to_tid[0]); |
479 | struct tid_ampdu_tx *tid_tx; |
480 | unsigned long timeout; |
481 | |
482 | rcu_read_lock(); |
483 | tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[*ptid]); |
484 | if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { |
485 | rcu_read_unlock(); |
486 | return; |
487 | } |
488 | |
489 | timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); |
490 | if (time_is_after_jiffies(timeout)) { |
491 | mod_timer(&tid_tx->session_timer, timeout); |
492 | rcu_read_unlock(); |
493 | return; |
494 | } |
495 | |
496 | rcu_read_unlock(); |
497 | |
498 | ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n", |
499 | sta->sta.addr, (u16)*ptid); |
500 | |
501 | ieee80211_stop_tx_ba_session(&sta->sta, *ptid); |
502 | } |
503 | |
504 | int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid, |
505 | u16 timeout) |
506 | { |
507 | struct sta_info *sta = container_of(pubsta, struct sta_info, sta); |
508 | struct ieee80211_sub_if_data *sdata = sta->sdata; |
509 | struct ieee80211_local *local = sdata->local; |
510 | struct tid_ampdu_tx *tid_tx; |
511 | int ret = 0; |
512 | |
513 | trace_api_start_tx_ba_session(pubsta, tid); |
514 | |
515 | if (WARN_ON_ONCE(!local->ops->ampdu_action)) |
516 | return -EINVAL; |
517 | |
518 | if ((tid >= IEEE80211_NUM_TIDS) || |
519 | !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) || |
520 | (local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW)) |
521 | return -EINVAL; |
522 | |
523 | ht_dbg(sdata, "Open BA session requested for %pM tid %u\n", |
524 | pubsta->addr, tid); |
525 | |
526 | if (sdata->vif.type != NL80211_IFTYPE_STATION && |
527 | sdata->vif.type != NL80211_IFTYPE_MESH_POINT && |
528 | sdata->vif.type != NL80211_IFTYPE_AP_VLAN && |
529 | sdata->vif.type != NL80211_IFTYPE_AP && |
530 | sdata->vif.type != NL80211_IFTYPE_ADHOC) |
531 | return -EINVAL; |
532 | |
533 | if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { |
534 | ht_dbg(sdata, |
535 | "BA sessions blocked - Denying BA session request %pM tid %d\n", |
536 | sta->sta.addr, tid); |
537 | return -EINVAL; |
538 | } |
539 | |
540 | /* |
541 | * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a |
542 | * member of an IBSS, and has no other existing Block Ack agreement |
543 | * with the recipient STA, then the initiating STA shall transmit a |
544 | * Probe Request frame to the recipient STA and shall not transmit an |
545 | * ADDBA Request frame unless it receives a Probe Response frame |
546 | * from the recipient within dot11ADDBAFailureTimeout. |
547 | * |
548 | * The probe request mechanism for ADDBA is currently not implemented, |
549 | * but we only build up Block Ack session with HT STAs. This information |
550 | * is set when we receive a bss info from a probe response or a beacon. |
551 | */ |
552 | if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC && |
553 | !sta->sta.ht_cap.ht_supported) { |
554 | ht_dbg(sdata, |
555 | "BA request denied - IBSS STA %pM does not advertise HT support\n", |
556 | pubsta->addr); |
557 | return -EINVAL; |
558 | } |
559 | |
560 | spin_lock_bh(&sta->lock); |
561 | |
562 | /* we have tried too many times, receiver does not want A-MPDU */ |
563 | if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) { |
564 | ret = -EBUSY; |
565 | goto err_unlock_sta; |
566 | } |
567 | |
568 | /* |
569 | * if we have tried more than HT_AGG_BURST_RETRIES times we |
570 | * will spread our requests in time to avoid stalling connection |
571 | * for too long |
572 | */ |
573 | if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES && |
574 | time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] + |
575 | HT_AGG_RETRIES_PERIOD)) { |
576 | ht_dbg(sdata, |
577 | "BA request denied - waiting a grace period after %d failed requests on %pM tid %u\n", |
578 | sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid); |
579 | ret = -EBUSY; |
580 | goto err_unlock_sta; |
581 | } |
582 | |
583 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
584 | /* check if the TID is not in aggregation flow already */ |
585 | if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) { |
586 | ht_dbg(sdata, |
587 | "BA request denied - session is not idle on %pM tid %u\n", |
588 | sta->sta.addr, tid); |
589 | ret = -EAGAIN; |
590 | goto err_unlock_sta; |
591 | } |
592 | |
593 | /* prepare A-MPDU MLME for Tx aggregation */ |
594 | tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC); |
595 | if (!tid_tx) { |
596 | ret = -ENOMEM; |
597 | goto err_unlock_sta; |
598 | } |
599 | |
600 | skb_queue_head_init(&tid_tx->pending); |
601 | __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); |
602 | |
603 | tid_tx->timeout = timeout; |
604 | |
605 | /* response timer */ |
606 | tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired; |
607 | tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid]; |
608 | init_timer(&tid_tx->addba_resp_timer); |
609 | |
610 | /* tx timer */ |
611 | tid_tx->session_timer.function = sta_tx_agg_session_timer_expired; |
612 | tid_tx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid]; |
613 | init_timer_deferrable(&tid_tx->session_timer); |
614 | |
615 | /* assign a dialog token */ |
616 | sta->ampdu_mlme.dialog_token_allocator++; |
617 | tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator; |
618 | |
619 | /* |
620 | * Finally, assign it to the start array; the work item will |
621 | * collect it and move it to the normal array. |
622 | */ |
623 | sta->ampdu_mlme.tid_start_tx[tid] = tid_tx; |
624 | |
625 | ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); |
626 | |
627 | /* this flow continues off the work */ |
628 | err_unlock_sta: |
629 | spin_unlock_bh(&sta->lock); |
630 | return ret; |
631 | } |
632 | EXPORT_SYMBOL(ieee80211_start_tx_ba_session); |
633 | |
634 | static void ieee80211_agg_tx_operational(struct ieee80211_local *local, |
635 | struct sta_info *sta, u16 tid) |
636 | { |
637 | struct tid_ampdu_tx *tid_tx; |
638 | |
639 | lockdep_assert_held(&sta->ampdu_mlme.mtx); |
640 | |
641 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
642 | |
643 | ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n", |
644 | sta->sta.addr, tid); |
645 | |
646 | drv_ampdu_action(local, sta->sdata, |
647 | IEEE80211_AMPDU_TX_OPERATIONAL, |
648 | &sta->sta, tid, NULL, tid_tx->buf_size); |
649 | |
650 | /* |
651 | * synchronize with TX path, while splicing the TX path |
652 | * should block so it won't put more packets onto pending. |
653 | */ |
654 | spin_lock_bh(&sta->lock); |
655 | |
656 | ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); |
657 | /* |
658 | * Now mark as operational. This will be visible |
659 | * in the TX path, and lets it go lock-free in |
660 | * the common case. |
661 | */ |
662 | set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); |
663 | ieee80211_agg_splice_finish(sta->sdata, tid); |
664 | |
665 | spin_unlock_bh(&sta->lock); |
666 | } |
667 | |
668 | void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid) |
669 | { |
670 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
671 | struct ieee80211_local *local = sdata->local; |
672 | struct sta_info *sta; |
673 | struct tid_ampdu_tx *tid_tx; |
674 | |
675 | trace_api_start_tx_ba_cb(sdata, ra, tid); |
676 | |
677 | if (tid >= IEEE80211_NUM_TIDS) { |
678 | ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n", |
679 | tid, IEEE80211_NUM_TIDS); |
680 | return; |
681 | } |
682 | |
683 | mutex_lock(&local->sta_mtx); |
684 | sta = sta_info_get_bss(sdata, ra); |
685 | if (!sta) { |
686 | mutex_unlock(&local->sta_mtx); |
687 | ht_dbg(sdata, "Could not find station: %pM\n", ra); |
688 | return; |
689 | } |
690 | |
691 | mutex_lock(&sta->ampdu_mlme.mtx); |
692 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
693 | |
694 | if (WARN_ON(!tid_tx)) { |
695 | ht_dbg(sdata, "addBA was not requested!\n"); |
696 | goto unlock; |
697 | } |
698 | |
699 | if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))) |
700 | goto unlock; |
701 | |
702 | if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) |
703 | ieee80211_agg_tx_operational(local, sta, tid); |
704 | |
705 | unlock: |
706 | mutex_unlock(&sta->ampdu_mlme.mtx); |
707 | mutex_unlock(&local->sta_mtx); |
708 | } |
709 | |
710 | void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, |
711 | const u8 *ra, u16 tid) |
712 | { |
713 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
714 | struct ieee80211_local *local = sdata->local; |
715 | struct ieee80211_ra_tid *ra_tid; |
716 | struct sk_buff *skb = dev_alloc_skb(0); |
717 | |
718 | if (unlikely(!skb)) |
719 | return; |
720 | |
721 | ra_tid = (struct ieee80211_ra_tid *) &skb->cb; |
722 | memcpy(&ra_tid->ra, ra, ETH_ALEN); |
723 | ra_tid->tid = tid; |
724 | |
725 | skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_START; |
726 | skb_queue_tail(&sdata->skb_queue, skb); |
727 | ieee80211_queue_work(&local->hw, &sdata->work); |
728 | } |
729 | EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe); |
730 | |
731 | int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, |
732 | enum ieee80211_agg_stop_reason reason) |
733 | { |
734 | int ret; |
735 | |
736 | mutex_lock(&sta->ampdu_mlme.mtx); |
737 | |
738 | ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason); |
739 | |
740 | mutex_unlock(&sta->ampdu_mlme.mtx); |
741 | |
742 | return ret; |
743 | } |
744 | |
745 | int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid) |
746 | { |
747 | struct sta_info *sta = container_of(pubsta, struct sta_info, sta); |
748 | struct ieee80211_sub_if_data *sdata = sta->sdata; |
749 | struct ieee80211_local *local = sdata->local; |
750 | struct tid_ampdu_tx *tid_tx; |
751 | int ret = 0; |
752 | |
753 | trace_api_stop_tx_ba_session(pubsta, tid); |
754 | |
755 | if (!local->ops->ampdu_action) |
756 | return -EINVAL; |
757 | |
758 | if (tid >= IEEE80211_NUM_TIDS) |
759 | return -EINVAL; |
760 | |
761 | spin_lock_bh(&sta->lock); |
762 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
763 | |
764 | if (!tid_tx) { |
765 | ret = -ENOENT; |
766 | goto unlock; |
767 | } |
768 | |
769 | if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { |
770 | /* already in progress stopping it */ |
771 | ret = 0; |
772 | goto unlock; |
773 | } |
774 | |
775 | set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state); |
776 | ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); |
777 | |
778 | unlock: |
779 | spin_unlock_bh(&sta->lock); |
780 | return ret; |
781 | } |
782 | EXPORT_SYMBOL(ieee80211_stop_tx_ba_session); |
783 | |
784 | void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid) |
785 | { |
786 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
787 | struct ieee80211_local *local = sdata->local; |
788 | struct sta_info *sta; |
789 | struct tid_ampdu_tx *tid_tx; |
790 | |
791 | trace_api_stop_tx_ba_cb(sdata, ra, tid); |
792 | |
793 | if (tid >= IEEE80211_NUM_TIDS) { |
794 | ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n", |
795 | tid, IEEE80211_NUM_TIDS); |
796 | return; |
797 | } |
798 | |
799 | ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n", ra, tid); |
800 | |
801 | mutex_lock(&local->sta_mtx); |
802 | |
803 | sta = sta_info_get_bss(sdata, ra); |
804 | if (!sta) { |
805 | ht_dbg(sdata, "Could not find station: %pM\n", ra); |
806 | goto unlock; |
807 | } |
808 | |
809 | mutex_lock(&sta->ampdu_mlme.mtx); |
810 | spin_lock_bh(&sta->lock); |
811 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
812 | |
813 | if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { |
814 | ht_dbg(sdata, |
815 | "unexpected callback to A-MPDU stop for %pM tid %d\n", |
816 | sta->sta.addr, tid); |
817 | goto unlock_sta; |
818 | } |
819 | |
820 | if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop) |
821 | ieee80211_send_delba(sta->sdata, ra, tid, |
822 | WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE); |
823 | |
824 | ieee80211_remove_tid_tx(sta, tid); |
825 | |
826 | unlock_sta: |
827 | spin_unlock_bh(&sta->lock); |
828 | mutex_unlock(&sta->ampdu_mlme.mtx); |
829 | unlock: |
830 | mutex_unlock(&local->sta_mtx); |
831 | } |
832 | |
833 | void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, |
834 | const u8 *ra, u16 tid) |
835 | { |
836 | struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); |
837 | struct ieee80211_local *local = sdata->local; |
838 | struct ieee80211_ra_tid *ra_tid; |
839 | struct sk_buff *skb = dev_alloc_skb(0); |
840 | |
841 | if (unlikely(!skb)) |
842 | return; |
843 | |
844 | ra_tid = (struct ieee80211_ra_tid *) &skb->cb; |
845 | memcpy(&ra_tid->ra, ra, ETH_ALEN); |
846 | ra_tid->tid = tid; |
847 | |
848 | skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_STOP; |
849 | skb_queue_tail(&sdata->skb_queue, skb); |
850 | ieee80211_queue_work(&local->hw, &sdata->work); |
851 | } |
852 | EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe); |
853 | |
854 | |
855 | void ieee80211_process_addba_resp(struct ieee80211_local *local, |
856 | struct sta_info *sta, |
857 | struct ieee80211_mgmt *mgmt, |
858 | size_t len) |
859 | { |
860 | struct tid_ampdu_tx *tid_tx; |
861 | u16 capab, tid; |
862 | u8 buf_size; |
863 | |
864 | capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab); |
865 | tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; |
866 | buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; |
867 | |
868 | mutex_lock(&sta->ampdu_mlme.mtx); |
869 | |
870 | tid_tx = rcu_dereference_protected_tid_tx(sta, tid); |
871 | if (!tid_tx) |
872 | goto out; |
873 | |
874 | if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) { |
875 | ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n", |
876 | sta->sta.addr, tid); |
877 | goto out; |
878 | } |
879 | |
880 | del_timer_sync(&tid_tx->addba_resp_timer); |
881 | |
882 | ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n", |
883 | sta->sta.addr, tid); |
884 | |
885 | /* |
886 | * addba_resp_timer may have fired before we got here, and |
887 | * caused WANT_STOP to be set. If the stop then was already |
888 | * processed further, STOPPING might be set. |
889 | */ |
890 | if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) || |
891 | test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { |
892 | ht_dbg(sta->sdata, |
893 | "got addBA resp for %pM tid %d but we already gave up\n", |
894 | sta->sta.addr, tid); |
895 | goto out; |
896 | } |
897 | |
898 | /* |
899 | * IEEE 802.11-2007 7.3.1.14: |
900 | * In an ADDBA Response frame, when the Status Code field |
901 | * is set to 0, the Buffer Size subfield is set to a value |
902 | * of at least 1. |
903 | */ |
904 | if (le16_to_cpu(mgmt->u.action.u.addba_resp.status) |
905 | == WLAN_STATUS_SUCCESS && buf_size) { |
906 | if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED, |
907 | &tid_tx->state)) { |
908 | /* ignore duplicate response */ |
909 | goto out; |
910 | } |
911 | |
912 | tid_tx->buf_size = buf_size; |
913 | |
914 | if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)) |
915 | ieee80211_agg_tx_operational(local, sta, tid); |
916 | |
917 | sta->ampdu_mlme.addba_req_num[tid] = 0; |
918 | |
919 | if (tid_tx->timeout) { |
920 | mod_timer(&tid_tx->session_timer, |
921 | TU_TO_EXP_TIME(tid_tx->timeout)); |
922 | tid_tx->last_tx = jiffies; |
923 | } |
924 | |
925 | } else { |
926 | ___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED); |
927 | } |
928 | |
929 | out: |
930 | mutex_unlock(&sta->ampdu_mlme.mtx); |
931 | } |
932 |
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