2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
5 * Copyright 2008-2010 Johannes Berg <johannes@sipsolutions.net>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/export.h>
13 #include <linux/etherdevice.h>
14 #include <net/mac80211.h>
15 #include <asm/unaligned.h>
16 #include "ieee80211_i.h"
23 void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
26 struct ieee80211_local *local = hw_to_local(hw);
27 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
30 skb->pkt_type = IEEE80211_TX_STATUS_MSG;
31 skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
32 &local->skb_queue : &local->skb_queue_unreliable, skb);
33 tmp = skb_queue_len(&local->skb_queue) +
34 skb_queue_len(&local->skb_queue_unreliable);
35 while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
36 (skb = skb_dequeue(&local->skb_queue_unreliable))) {
37 ieee80211_free_txskb(hw, skb);
39 I802_DEBUG_INC(local->tx_status_drop);
41 tasklet_schedule(&local->tasklet);
43 EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
45 static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
49 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
50 struct ieee80211_hdr *hdr = (void *)skb->data;
54 * This skb 'survived' a round-trip through the driver, and
55 * hopefully the driver didn't mangle it too badly. However,
56 * we can definitely not rely on the control information
57 * being correct. Clear it so we don't get junk there, and
58 * indicate that it needs new processing, but must not be
59 * modified/encrypted again.
61 memset(&info->control, 0, sizeof(info->control));
63 info->control.jiffies = jiffies;
64 info->control.vif = &sta->sdata->vif;
65 info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
66 IEEE80211_TX_INTFL_RETRANSMISSION;
67 info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
69 sta->tx_filtered_count++;
72 * Clear more-data bit on filtered frames, it might be set
73 * but later frames might time out so it might have to be
74 * clear again ... It's all rather unlikely (this frame
75 * should time out first, right?) but let's not confuse
76 * peers unnecessarily.
78 if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
79 hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);
81 if (ieee80211_is_data_qos(hdr->frame_control)) {
82 u8 *p = ieee80211_get_qos_ctl(hdr);
83 int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
86 * Clear EOSP if set, this could happen e.g.
87 * if an absence period (us being a P2P GO)
90 if (*p & IEEE80211_QOS_CTL_EOSP)
91 *p &= ~IEEE80211_QOS_CTL_EOSP;
92 ac = ieee802_1d_to_ac[tid & 7];
98 * Clear the TX filter mask for this STA when sending the next
99 * packet. If the STA went to power save mode, this will happen
100 * when it wakes up for the next time.
102 set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
105 * This code races in the following way:
107 * (1) STA sends frame indicating it will go to sleep and does so
108 * (2) hardware/firmware adds STA to filter list, passes frame up
109 * (3) hardware/firmware processes TX fifo and suppresses a frame
110 * (4) we get TX status before having processed the frame and
111 * knowing that the STA has gone to sleep.
113 * This is actually quite unlikely even when both those events are
114 * processed from interrupts coming in quickly after one another or
115 * even at the same time because we queue both TX status events and
116 * RX frames to be processed by a tasklet and process them in the
117 * same order that they were received or TX status last. Hence, there
118 * is no race as long as the frame RX is processed before the next TX
119 * status, which drivers can ensure, see below.
121 * Note that this can only happen if the hardware or firmware can
122 * actually add STAs to the filter list, if this is done by the
123 * driver in response to set_tim() (which will only reduce the race
124 * this whole filtering tries to solve, not completely solve it)
125 * this situation cannot happen.
127 * To completely solve this race drivers need to make sure that they
128 * (a) don't mix the irq-safe/not irq-safe TX status/RX processing
130 * (b) always process RX events before TX status events if ordering
131 * can be unknown, for example with different interrupt status
133 * (c) if PS mode transitions are manual (i.e. the flag
134 * %IEEE80211_HW_AP_LINK_PS is set), always process PS state
135 * changes before calling TX status events if ordering can be
138 if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
139 skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
140 skb_queue_tail(&sta->tx_filtered[ac], skb);
141 sta_info_recalc_tim(sta);
143 if (!timer_pending(&local->sta_cleanup))
144 mod_timer(&local->sta_cleanup,
145 round_jiffies(jiffies +
146 STA_INFO_CLEANUP_INTERVAL));
150 if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
151 !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
152 /* Software retry the packet once */
153 info->flags |= IEEE80211_TX_INTFL_RETRIED;
154 ieee80211_add_pending_skb(local, skb);
158 ps_dbg_ratelimited(sta->sdata,
159 "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
160 skb_queue_len(&sta->tx_filtered[ac]),
161 !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);
162 ieee80211_free_txskb(&local->hw, skb);
165 static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
167 struct tid_ampdu_tx *tid_tx;
169 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
170 if (!tid_tx || !tid_tx->bar_pending)
173 tid_tx->bar_pending = false;
174 ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);
177 static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
179 struct ieee80211_mgmt *mgmt = (void *) skb->data;
180 struct ieee80211_local *local = sta->local;
181 struct ieee80211_sub_if_data *sdata = sta->sdata;
183 if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)
184 sta->last_rx = jiffies;
186 if (ieee80211_is_data_qos(mgmt->frame_control)) {
187 struct ieee80211_hdr *hdr = (void *) skb->data;
188 u8 *qc = ieee80211_get_qos_ctl(hdr);
189 u16 tid = qc[0] & 0xf;
191 ieee80211_check_pending_bar(sta, hdr->addr1, tid);
194 if (ieee80211_is_action(mgmt->frame_control) &&
195 mgmt->u.action.category == WLAN_CATEGORY_HT &&
196 mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
197 sdata->vif.type == NL80211_IFTYPE_STATION &&
198 ieee80211_sdata_running(sdata)) {
200 * This update looks racy, but isn't -- if we come
201 * here we've definitely got a station that we're
202 * talking to, and on a managed interface that can
203 * only be the AP. And the only other place updating
204 * this variable in managed mode is before association.
206 switch (mgmt->u.action.u.ht_smps.smps_control) {
207 case WLAN_HT_SMPS_CONTROL_DYNAMIC:
208 sdata->smps_mode = IEEE80211_SMPS_DYNAMIC;
210 case WLAN_HT_SMPS_CONTROL_STATIC:
211 sdata->smps_mode = IEEE80211_SMPS_STATIC;
213 case WLAN_HT_SMPS_CONTROL_DISABLED:
214 default: /* shouldn't happen since we don't send that */
215 sdata->smps_mode = IEEE80211_SMPS_OFF;
219 ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
223 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
225 struct tid_ampdu_tx *tid_tx;
227 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
231 tid_tx->failed_bar_ssn = ssn;
232 tid_tx->bar_pending = true;
235 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
237 int len = sizeof(struct ieee80211_radiotap_header);
239 /* IEEE80211_RADIOTAP_RATE rate */
240 if (info->status.rates[0].idx >= 0 &&
241 !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS))
244 /* IEEE80211_RADIOTAP_TX_FLAGS */
247 /* IEEE80211_RADIOTAP_DATA_RETRIES */
250 /* IEEE80211_TX_RC_MCS */
251 if (info->status.rates[0].idx >= 0 &&
252 info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
258 static void ieee80211_add_tx_radiotap_header(struct ieee80211_supported_band
259 *sband, struct sk_buff *skb,
260 int retry_count, int rtap_len)
262 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
263 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
264 struct ieee80211_radiotap_header *rthdr;
268 rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len);
270 memset(rthdr, 0, rtap_len);
271 rthdr->it_len = cpu_to_le16(rtap_len);
273 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
274 (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
275 pos = (unsigned char *)(rthdr + 1);
278 * XXX: Once radiotap gets the bitmap reset thing the vendor
279 * extensions proposal contains, we can actually report
280 * the whole set of tries we did.
283 /* IEEE80211_RADIOTAP_RATE */
284 if (info->status.rates[0].idx >= 0 &&
285 !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) {
286 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
287 *pos = sband->bitrates[info->status.rates[0].idx].bitrate / 5;
288 /* padding for tx flags */
292 /* IEEE80211_RADIOTAP_TX_FLAGS */
294 if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
295 !is_multicast_ether_addr(hdr->addr1))
296 txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
298 if ((info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
299 (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
300 txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
301 else if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
302 txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
304 put_unaligned_le16(txflags, pos);
307 /* IEEE80211_RADIOTAP_DATA_RETRIES */
308 /* for now report the total retry_count */
312 /* IEEE80211_TX_RC_MCS */
313 if (info->status.rates[0].idx >= 0 &&
314 info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
315 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
316 pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
317 IEEE80211_RADIOTAP_MCS_HAVE_GI |
318 IEEE80211_RADIOTAP_MCS_HAVE_BW;
319 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
320 pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
321 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
322 pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
323 if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
324 pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
325 pos[2] = info->status.rates[0].idx;
331 static void ieee80211_report_used_skb(struct ieee80211_local *local,
332 struct sk_buff *skb, bool dropped)
334 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
335 struct ieee80211_hdr *hdr = (void *)skb->data;
336 bool acked = info->flags & IEEE80211_TX_STAT_ACK;
341 if (info->flags & (IEEE80211_TX_INTFL_NL80211_FRAME_TX |
342 IEEE80211_TX_INTFL_MLME_CONN_TX)) {
343 struct ieee80211_sub_if_data *sdata = NULL;
344 struct ieee80211_sub_if_data *iter_sdata;
345 u64 cookie = (unsigned long)skb;
350 list_for_each_entry_rcu(iter_sdata, &local->interfaces,
352 if (!iter_sdata->dev)
355 if (skb->dev == iter_sdata->dev) {
361 sdata = rcu_dereference(local->p2p_sdata);
366 } else if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
367 ieee80211_mgd_conn_tx_status(sdata, hdr->frame_control,
369 } else if (ieee80211_is_nullfunc(hdr->frame_control) ||
370 ieee80211_is_qos_nullfunc(hdr->frame_control)) {
371 cfg80211_probe_status(sdata->dev, hdr->addr1,
372 cookie, acked, GFP_ATOMIC);
374 cfg80211_mgmt_tx_status(&sdata->wdev, cookie, skb->data,
375 skb->len, acked, GFP_ATOMIC);
381 if (unlikely(info->ack_frame_id)) {
382 struct sk_buff *ack_skb;
385 spin_lock_irqsave(&local->ack_status_lock, flags);
386 ack_skb = idr_find(&local->ack_status_frames,
389 idr_remove(&local->ack_status_frames,
391 spin_unlock_irqrestore(&local->ack_status_lock, flags);
395 /* consumes ack_skb */
396 skb_complete_wifi_ack(ack_skb, acked);
398 dev_kfree_skb_any(ack_skb);
405 * Use a static threshold for now, best value to be determined
407 * Should it depend on:
408 * - on # of retransmissions
409 * - current throughput (higher value for higher tpt)?
411 #define STA_LOST_PKT_THRESHOLD 50
413 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
415 struct sk_buff *skb2;
416 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
417 struct ieee80211_local *local = hw_to_local(hw);
418 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
420 struct ieee80211_supported_band *sband;
421 struct ieee80211_sub_if_data *sdata;
422 struct net_device *prev_dev = NULL;
423 struct sta_info *sta, *tmp;
424 int retry_count = -1, i;
428 struct ieee80211_bar *bar;
431 for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
432 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
433 !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
434 /* just the first aggr frame carry status info */
435 info->status.rates[i].idx = -1;
436 info->status.rates[i].count = 0;
438 } else if (info->status.rates[i].idx < 0) {
440 } else if (i >= hw->max_report_rates) {
441 /* the HW cannot have attempted that rate */
442 info->status.rates[i].idx = -1;
443 info->status.rates[i].count = 0;
447 retry_count += info->status.rates[i].count;
456 sband = local->hw.wiphy->bands[info->band];
457 fc = hdr->frame_control;
459 for_each_sta_info(local, hdr->addr1, sta, tmp) {
460 /* skip wrong virtual interface */
461 if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
464 if (info->flags & IEEE80211_TX_STATUS_EOSP)
465 clear_sta_flag(sta, WLAN_STA_SP);
467 acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
468 if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
470 * The STA is in power save mode, so assume
471 * that this TX packet failed because of that.
473 ieee80211_handle_filtered_frame(local, sta, skb);
478 /* mesh Peer Service Period support */
479 if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
480 ieee80211_is_data_qos(fc))
481 ieee80211_mpsp_trigger_process(
482 ieee80211_get_qos_ctl(hdr),
485 if ((local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) &&
487 sta->last_tx_rate = info->status.rates[rates_idx];
489 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
490 (ieee80211_is_data_qos(fc))) {
494 qc = ieee80211_get_qos_ctl(hdr);
496 ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
497 & IEEE80211_SCTL_SEQ);
498 ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
502 if (!acked && ieee80211_is_back_req(fc)) {
506 * BAR failed, store the last SSN and retry sending
507 * the BAR when the next unicast transmission on the
510 bar = (struct ieee80211_bar *) skb->data;
511 control = le16_to_cpu(bar->control);
512 if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
513 u16 ssn = le16_to_cpu(bar->start_seq_num);
516 IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
517 IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
519 ieee80211_set_bar_pending(sta, tid, ssn);
523 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
524 ieee80211_handle_filtered_frame(local, sta, skb);
529 sta->tx_retry_failed++;
530 sta->tx_retry_count += retry_count;
533 rate_control_tx_status(local, sband, sta, skb);
534 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
535 ieee80211s_update_metric(local, sta, skb);
537 if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
538 ieee80211_frame_acked(sta, skb);
540 if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
541 (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS))
542 ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data, acked);
544 if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) {
545 if (info->flags & IEEE80211_TX_STAT_ACK) {
546 if (sta->lost_packets)
547 sta->lost_packets = 0;
548 } else if (++sta->lost_packets >= STA_LOST_PKT_THRESHOLD) {
549 cfg80211_cqm_pktloss_notify(sta->sdata->dev,
553 sta->lost_packets = 0;
558 sta->last_ack_signal = info->status.ack_signal;
563 ieee80211_led_tx(local, 0);
566 * Fragments are passed to low-level drivers as separate skbs, so these
567 * are actually fragments, not frames. Update frame counters only for
568 * the first fragment of the frame. */
569 if (info->flags & IEEE80211_TX_STAT_ACK) {
570 if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
571 local->dot11TransmittedFrameCount++;
572 if (is_multicast_ether_addr(hdr->addr1))
573 local->dot11MulticastTransmittedFrameCount++;
575 local->dot11RetryCount++;
577 local->dot11MultipleRetryCount++;
580 /* This counter shall be incremented for an acknowledged MPDU
581 * with an individual address in the address 1 field or an MPDU
582 * with a multicast address in the address 1 field of type Data
584 if (!is_multicast_ether_addr(hdr->addr1) ||
585 ieee80211_is_data(fc) ||
586 ieee80211_is_mgmt(fc))
587 local->dot11TransmittedFragmentCount++;
589 if (ieee80211_is_first_frag(hdr->seq_ctrl))
590 local->dot11FailedCount++;
593 if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
594 (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) &&
595 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
596 local->ps_sdata && !(local->scanning)) {
597 if (info->flags & IEEE80211_TX_STAT_ACK) {
598 local->ps_sdata->u.mgd.flags |=
599 IEEE80211_STA_NULLFUNC_ACKED;
601 mod_timer(&local->dynamic_ps_timer, jiffies +
602 msecs_to_jiffies(10));
605 ieee80211_report_used_skb(local, skb, false);
607 /* this was a transmitted frame, but now we want to reuse it */
610 /* Need to make a copy before skb->cb gets cleared */
611 send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
612 !(ieee80211_is_data(fc));
615 * This is a bit racy but we can avoid a lot of work
618 if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
623 /* send frame to monitor interfaces now */
624 rtap_len = ieee80211_tx_radiotap_len(info);
625 if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
626 pr_err("ieee80211_tx_status: headroom too small\n");
630 ieee80211_add_tx_radiotap_header(sband, skb, retry_count, rtap_len);
632 /* XXX: is this sufficient for BPF? */
633 skb_set_mac_header(skb, 0);
634 skb->ip_summed = CHECKSUM_UNNECESSARY;
635 skb->pkt_type = PACKET_OTHERHOST;
636 skb->protocol = htons(ETH_P_802_2);
637 memset(skb->cb, 0, sizeof(skb->cb));
640 list_for_each_entry_rcu(sdata, &local->interfaces, list) {
641 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
642 if (!ieee80211_sdata_running(sdata))
645 if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
650 skb2 = skb_clone(skb, GFP_ATOMIC);
652 skb2->dev = prev_dev;
657 prev_dev = sdata->dev;
668 EXPORT_SYMBOL(ieee80211_tx_status);
670 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
672 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
673 cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
674 num_packets, GFP_ATOMIC);
676 EXPORT_SYMBOL(ieee80211_report_low_ack);
678 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
680 struct ieee80211_local *local = hw_to_local(hw);
682 ieee80211_report_used_skb(local, skb, true);
683 dev_kfree_skb_any(skb);
685 EXPORT_SYMBOL(ieee80211_free_txskb);
687 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
688 struct sk_buff_head *skbs)
692 while ((skb = __skb_dequeue(skbs)))
693 ieee80211_free_txskb(hw, skb);