source: src/linux/universal/linux-4.9/net/mac80211/agg-rx.c @ 31662

Last change on this file since 31662 was 31662, checked in by brainslayer, 11 days ago

use new squashfs in all kernels

File size: 15.1 KB
Line 
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 * Copyright(c) 2015 Intel Deutschland GmbH
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 */
16
17/**
18 * DOC: RX A-MPDU aggregation
19 *
20 * Aggregation on the RX side requires only implementing the
21 * @ampdu_action callback that is invoked to start/stop any
22 * block-ack sessions for RX aggregation.
23 *
24 * When RX aggregation is started by the peer, the driver is
25 * notified via @ampdu_action function, with the
26 * %IEEE80211_AMPDU_RX_START action, and may reject the request
27 * in which case a negative response is sent to the peer, if it
28 * accepts it a positive response is sent.
29 *
30 * While the session is active, the device/driver are required
31 * to de-aggregate frames and pass them up one by one to mac80211,
32 * which will handle the reorder buffer.
33 *
34 * When the aggregation session is stopped again by the peer or
35 * ourselves, the driver's @ampdu_action function will be called
36 * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the
37 * call must not fail.
38 */
39
40#include <linux/ieee80211.h>
41#include <linux/slab.h>
42#include <linux/export.h>
43#include <net/mac80211.h>
44#include "ieee80211_i.h"
45#include "driver-ops.h"
46
47static void ieee80211_free_tid_rx(struct rcu_head *h)
48{
49        struct tid_ampdu_rx *tid_rx =
50                container_of(h, struct tid_ampdu_rx, rcu_head);
51        int i;
52
53        for (i = 0; i < tid_rx->buf_size; i++)
54                __skb_queue_purge(&tid_rx->reorder_buf[i]);
55        kfree(tid_rx->reorder_buf);
56        kfree(tid_rx->reorder_time);
57        kfree(tid_rx);
58}
59
60void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
61                                     u16 initiator, u16 reason, bool tx)
62{
63        struct ieee80211_local *local = sta->local;
64        struct tid_ampdu_rx *tid_rx;
65        struct ieee80211_ampdu_params params = {
66                .sta = &sta->sta,
67                .action = IEEE80211_AMPDU_RX_STOP,
68                .tid = tid,
69                .amsdu = false,
70                .timeout = 0,
71                .ssn = 0,
72        };
73
74        lockdep_assert_held(&sta->ampdu_mlme.mtx);
75
76        tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
77                                        lockdep_is_held(&sta->ampdu_mlme.mtx));
78
79        if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid))
80                return;
81
82        RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
83        __clear_bit(tid, sta->ampdu_mlme.agg_session_valid);
84
85        ht_dbg(sta->sdata,
86               "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
87               sta->sta.addr, tid,
88               initiator == WLAN_BACK_RECIPIENT ? "recipient" : "inititator",
89               (int)reason);
90
91        if (drv_ampdu_action(local, sta->sdata, &params))
92                sdata_info(sta->sdata,
93                           "HW problem - can not stop rx aggregation for %pM tid %d\n",
94                           sta->sta.addr, tid);
95
96        /* check if this is a self generated aggregation halt */
97        if (initiator == WLAN_BACK_RECIPIENT && tx)
98                ieee80211_send_delba(sta->sdata, sta->sta.addr,
99                                     tid, WLAN_BACK_RECIPIENT, reason);
100
101        /*
102         * return here in case tid_rx is not assigned - which will happen if
103         * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set.
104         */
105        if (!tid_rx)
106                return;
107
108        del_timer_sync(&tid_rx->session_timer);
109
110        /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
111        spin_lock_bh(&tid_rx->reorder_lock);
112        tid_rx->removed = true;
113        spin_unlock_bh(&tid_rx->reorder_lock);
114        del_timer_sync(&tid_rx->reorder_timer);
115
116        call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
117}
118
119void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
120                                    u16 initiator, u16 reason, bool tx)
121{
122        mutex_lock(&sta->ampdu_mlme.mtx);
123        ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
124        mutex_unlock(&sta->ampdu_mlme.mtx);
125}
126
127void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
128                                  const u8 *addr)
129{
130        struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
131        struct sta_info *sta;
132        int i;
133
134        rcu_read_lock();
135        sta = sta_info_get_bss(sdata, addr);
136        if (!sta) {
137                rcu_read_unlock();
138                return;
139        }
140
141        for (i = 0; i < IEEE80211_NUM_TIDS; i++)
142                if (ba_rx_bitmap & BIT(i))
143                        set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
144
145        ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
146        rcu_read_unlock();
147}
148EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
149
150/*
151 * After accepting the AddBA Request we activated a timer,
152 * resetting it after each frame that arrives from the originator.
153 */
154static void sta_rx_agg_session_timer_expired(unsigned long data)
155{
156        /* not an elegant detour, but there is no choice as the timer passes
157         * only one argument, and various sta_info are needed here, so init
158         * flow in sta_info_create gives the TID as data, while the timer_to_id
159         * array gives the sta through container_of */
160        u8 *ptid = (u8 *)data;
161        u8 *timer_to_id = ptid - *ptid;
162        struct sta_info *sta = container_of(timer_to_id, struct sta_info,
163                                         timer_to_tid[0]);
164        struct tid_ampdu_rx *tid_rx;
165        unsigned long timeout;
166
167        rcu_read_lock();
168        tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]);
169        if (!tid_rx) {
170                rcu_read_unlock();
171                return;
172        }
173
174        timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
175        if (time_is_after_jiffies(timeout)) {
176                mod_timer(&tid_rx->session_timer, timeout);
177                rcu_read_unlock();
178                return;
179        }
180        rcu_read_unlock();
181
182        ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
183               sta->sta.addr, (u16)*ptid);
184
185        set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired);
186        ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
187}
188
189static void sta_rx_agg_reorder_timer_expired(unsigned long data)
190{
191        u8 *ptid = (u8 *)data;
192        u8 *timer_to_id = ptid - *ptid;
193        struct sta_info *sta = container_of(timer_to_id, struct sta_info,
194                        timer_to_tid[0]);
195
196        rcu_read_lock();
197        ieee80211_release_reorder_timeout(sta, *ptid);
198        rcu_read_unlock();
199}
200
201static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
202                                      u8 dialog_token, u16 status, u16 policy,
203                                      u16 buf_size, u16 timeout)
204{
205        struct ieee80211_local *local = sdata->local;
206        struct sk_buff *skb;
207        struct ieee80211_mgmt *mgmt;
208        bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
209        u16 capab;
210
211        skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
212        if (!skb)
213                return;
214
215        skb_reserve(skb, local->hw.extra_tx_headroom);
216        mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
217        memset(mgmt, 0, 24);
218        memcpy(mgmt->da, da, ETH_ALEN);
219        memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
220        if (sdata->vif.type == NL80211_IFTYPE_AP ||
221            sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
222            sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
223                memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
224        else if (sdata->vif.type == NL80211_IFTYPE_STATION)
225                memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
226        else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
227                memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
228
229        mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
230                                          IEEE80211_STYPE_ACTION);
231
232        skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
233        mgmt->u.action.category = WLAN_CATEGORY_BACK;
234        mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
235        mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
236
237        capab = (u16)(amsdu << 0);      /* bit 0 A-MSDU support */
238        capab |= (u16)(policy << 1);    /* bit 1 aggregation policy */
239        capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
240        capab |= (u16)(buf_size << 6);  /* bit 15:6 max size of aggregation */
241
242        mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
243        mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
244        mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
245
246        ieee80211_tx_skb(sdata, skb);
247}
248
249void __ieee80211_start_rx_ba_session(struct sta_info *sta,
250                                     u8 dialog_token, u16 timeout,
251                                     u16 start_seq_num, u16 ba_policy, u16 tid,
252                                     u16 buf_size, bool tx, bool auto_seq)
253{
254        struct ieee80211_local *local = sta->sdata->local;
255        struct tid_ampdu_rx *tid_agg_rx;
256        struct ieee80211_ampdu_params params = {
257                .sta = &sta->sta,
258                .action = IEEE80211_AMPDU_RX_START,
259                .tid = tid,
260                .amsdu = false,
261                .timeout = timeout,
262                .ssn = start_seq_num,
263        };
264        int i, ret = -EOPNOTSUPP;
265        u16 status = WLAN_STATUS_REQUEST_DECLINED;
266
267        if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
268                ht_dbg(sta->sdata,
269                       "STA %pM requests BA session on unsupported tid %d\n",
270                       sta->sta.addr, tid);
271                goto end_no_lock;
272        }
273
274        if (!sta->sta.ht_cap.ht_supported) {
275                ht_dbg(sta->sdata,
276                       "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
277                       sta->sta.addr, tid);
278                /* send a response anyway, it's an error case if we get here */
279                goto end_no_lock;
280        }
281
282        if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
283                ht_dbg(sta->sdata,
284                       "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
285                       sta->sta.addr, tid);
286                goto end_no_lock;
287        }
288
289        /* sanity check for incoming parameters:
290         * check if configuration can support the BA policy
291         * and if buffer size does not exceeds max value */
292        /* XXX: check own ht delayed BA capability?? */
293        if (((ba_policy != 1) &&
294             (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
295            (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
296                status = WLAN_STATUS_INVALID_QOS_PARAM;
297                ht_dbg_ratelimited(sta->sdata,
298                                   "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
299                                   sta->sta.addr, tid, ba_policy, buf_size);
300                goto end_no_lock;
301        }
302        /* determine default buffer size */
303        if (buf_size == 0)
304                buf_size = IEEE80211_MAX_AMPDU_BUF;
305
306        /* make sure the size doesn't exceed the maximum supported by the hw */
307        if (buf_size > sta->sta.max_rx_aggregation_subframes)
308                buf_size = sta->sta.max_rx_aggregation_subframes;
309        params.buf_size = buf_size;
310
311        ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
312               buf_size, sta->sta.addr);
313
314        /* examine state machine */
315        mutex_lock(&sta->ampdu_mlme.mtx);
316
317        if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
318                if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
319                        ht_dbg_ratelimited(sta->sdata,
320                                           "updated AddBA Req from %pM on tid %u\n",
321                                           sta->sta.addr, tid);
322                        /* We have no API to update the timeout value in the
323                         * driver so reject the timeout update.
324                         */
325                        status = WLAN_STATUS_REQUEST_DECLINED;
326                        ieee80211_send_addba_resp(sta->sdata, sta->sta.addr,
327                                                  tid, dialog_token, status,
328                                                  1, buf_size, timeout);
329                        goto end;
330                }
331
332                ht_dbg_ratelimited(sta->sdata,
333                                   "unexpected AddBA Req from %pM on tid %u\n",
334                                   sta->sta.addr, tid);
335
336                /* delete existing Rx BA session on the same tid */
337                ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
338                                                WLAN_STATUS_UNSPECIFIED_QOS,
339                                                false);
340        }
341
342        if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
343                ret = drv_ampdu_action(local, sta->sdata, &params);
344                ht_dbg(sta->sdata,
345                       "Rx A-MPDU request on %pM tid %d result %d\n",
346                       sta->sta.addr, tid, ret);
347                if (!ret)
348                        status = WLAN_STATUS_SUCCESS;
349                goto end;
350        }
351
352        /* prepare A-MPDU MLME for Rx aggregation */
353        tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
354        if (!tid_agg_rx)
355                goto end;
356
357        spin_lock_init(&tid_agg_rx->reorder_lock);
358
359        /* rx timer */
360        tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired;
361        tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
362        init_timer_deferrable(&tid_agg_rx->session_timer);
363
364        /* rx reorder timer */
365        tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired;
366        tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid];
367        init_timer(&tid_agg_rx->reorder_timer);
368
369        /* prepare reordering buffer */
370        tid_agg_rx->reorder_buf =
371                kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
372        tid_agg_rx->reorder_time =
373                kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
374        if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
375                kfree(tid_agg_rx->reorder_buf);
376                kfree(tid_agg_rx->reorder_time);
377                kfree(tid_agg_rx);
378                goto end;
379        }
380
381        for (i = 0; i < buf_size; i++)
382                __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
383
384        ret = drv_ampdu_action(local, sta->sdata, &params);
385        ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
386               sta->sta.addr, tid, ret);
387        if (ret) {
388                kfree(tid_agg_rx->reorder_buf);
389                kfree(tid_agg_rx->reorder_time);
390                kfree(tid_agg_rx);
391                goto end;
392        }
393
394        /* update data */
395        tid_agg_rx->ssn = start_seq_num;
396        tid_agg_rx->head_seq_num = start_seq_num;
397        tid_agg_rx->buf_size = buf_size;
398        tid_agg_rx->timeout = timeout;
399        tid_agg_rx->stored_mpdu_num = 0;
400        tid_agg_rx->auto_seq = auto_seq;
401        tid_agg_rx->started = false;
402        tid_agg_rx->reorder_buf_filtered = 0;
403        status = WLAN_STATUS_SUCCESS;
404
405        /* activate it for RX */
406        rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
407
408        if (timeout) {
409                mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
410                tid_agg_rx->last_rx = jiffies;
411        }
412
413end:
414        if (status == WLAN_STATUS_SUCCESS) {
415                __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
416                __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
417                sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
418        }
419        mutex_unlock(&sta->ampdu_mlme.mtx);
420
421end_no_lock:
422        if (tx)
423                ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
424                                          dialog_token, status, 1, buf_size,
425                                          timeout);
426}
427
428void ieee80211_process_addba_request(struct ieee80211_local *local,
429                                     struct sta_info *sta,
430                                     struct ieee80211_mgmt *mgmt,
431                                     size_t len)
432{
433        u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
434        u8 dialog_token;
435
436        /* extract session parameters from addba request frame */
437        dialog_token = mgmt->u.action.u.addba_req.dialog_token;
438        timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
439        start_seq_num =
440                le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
441
442        capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
443        ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
444        tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
445        buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
446
447        __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
448                                        start_seq_num, ba_policy, tid,
449                                        buf_size, true, false);
450}
451
452void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif,
453                                        const u8 *addr, u16 tid)
454{
455        struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
456        struct ieee80211_local *local = sdata->local;
457        struct ieee80211_rx_agg *rx_agg;
458        struct sk_buff *skb = dev_alloc_skb(0);
459
460        if (unlikely(!skb))
461                return;
462
463        rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
464        memcpy(&rx_agg->addr, addr, ETH_ALEN);
465        rx_agg->tid = tid;
466
467        skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START;
468        skb_queue_tail(&sdata->skb_queue, skb);
469        ieee80211_queue_work(&local->hw, &sdata->work);
470}
471EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl);
472
473void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif,
474                                       const u8 *addr, u16 tid)
475{
476        struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
477        struct ieee80211_local *local = sdata->local;
478        struct ieee80211_rx_agg *rx_agg;
479        struct sk_buff *skb = dev_alloc_skb(0);
480
481        if (unlikely(!skb))
482                return;
483
484        rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
485        memcpy(&rx_agg->addr, addr, ETH_ALEN);
486        rx_agg->tid = tid;
487
488        skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP;
489        skb_queue_tail(&sdata->skb_queue, skb);
490        ieee80211_queue_work(&local->hw, &sdata->work);
491}
492EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl);
Note: See TracBrowser for help on using the repository browser.