/* * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2006-2007 Jiri Benc * Copyright 2008-2010 Johannes Berg * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include "ieee80211_i.h" #include "rate.h" #include "mesh.h" #include "led.h" #include "wme.h" void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw, struct sk_buff *skb) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); int tmp; skb->pkt_type = IEEE80211_TX_STATUS_MSG; skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ? &local->skb_queue : &local->skb_queue_unreliable, skb); tmp = skb_queue_len(&local->skb_queue) + skb_queue_len(&local->skb_queue_unreliable); while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT && (skb = skb_dequeue(&local->skb_queue_unreliable))) { dev_kfree_skb_irq(skb); tmp--; I802_DEBUG_INC(local->tx_status_drop); } tasklet_schedule(&local->tasklet); } EXPORT_SYMBOL(ieee80211_tx_status_irqsafe); static void ieee80211_handle_filtered_frame(struct ieee80211_local *local, struct sta_info *sta, struct sk_buff *skb) { struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct ieee80211_hdr *hdr = (void *)skb->data; int ac; /* * This skb 'survived' a round-trip through the driver, and * hopefully the driver didn't mangle it too badly. However, * we can definitely not rely on the control information * being correct. Clear it so we don't get junk there, and * indicate that it needs new processing, but must not be * modified/encrypted again. */ memset(&info->control, 0, sizeof(info->control)); info->control.jiffies = jiffies; info->control.vif = &sta->sdata->vif; info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING | IEEE80211_TX_INTFL_RETRANSMISSION; info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS; sta->tx_filtered_count++; /* * Clear more-data bit on filtered frames, it might be set * but later frames might time out so it might have to be * clear again ... It's all rather unlikely (this frame * should time out first, right?) but let's not confuse * peers unnecessarily. */ if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA)) hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA); if (ieee80211_is_data_qos(hdr->frame_control)) { u8 *p = ieee80211_get_qos_ctl(hdr); int tid = *p & IEEE80211_QOS_CTL_TID_MASK; /* * Clear EOSP if set, this could happen e.g. * if an absence period (us being a P2P GO) * shortens the SP. */ if (*p & IEEE80211_QOS_CTL_EOSP) *p &= ~IEEE80211_QOS_CTL_EOSP; ac = ieee802_1d_to_ac[tid & 7]; } else { ac = IEEE80211_AC_BE; } /* * Clear the TX filter mask for this STA when sending the next * packet. If the STA went to power save mode, this will happen * when it wakes up for the next time. */ set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT); /* * This code races in the following way: * * (1) STA sends frame indicating it will go to sleep and does so * (2) hardware/firmware adds STA to filter list, passes frame up * (3) hardware/firmware processes TX fifo and suppresses a frame * (4) we get TX status before having processed the frame and * knowing that the STA has gone to sleep. * * This is actually quite unlikely even when both those events are * processed from interrupts coming in quickly after one another or * even at the same time because we queue both TX status events and * RX frames to be processed by a tasklet and process them in the * same order that they were received or TX status last. Hence, there * is no race as long as the frame RX is processed before the next TX * status, which drivers can ensure, see below. * * Note that this can only happen if the hardware or firmware can * actually add STAs to the filter list, if this is done by the * driver in response to set_tim() (which will only reduce the race * this whole filtering tries to solve, not completely solve it) * this situation cannot happen. * * To completely solve this race drivers need to make sure that they * (a) don't mix the irq-safe/not irq-safe TX status/RX processing * functions and * (b) always process RX events before TX status events if ordering * can be unknown, for example with different interrupt status * bits. * (c) if PS mode transitions are manual (i.e. the flag * %IEEE80211_HW_AP_LINK_PS is set), always process PS state * changes before calling TX status events if ordering can be * unknown. */ if (test_sta_flag(sta, WLAN_STA_PS_STA) && skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) { skb_queue_tail(&sta->tx_filtered[ac], skb); sta_info_recalc_tim(sta); if (!timer_pending(&local->sta_cleanup)) mod_timer(&local->sta_cleanup, round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL)); return; } if (!test_sta_flag(sta, WLAN_STA_PS_STA) && !(info->flags & IEEE80211_TX_INTFL_RETRIED)) { /* Software retry the packet once */ info->flags |= IEEE80211_TX_INTFL_RETRIED; ieee80211_add_pending_skb(local, skb); return; } #ifdef CONFIG_MAC80211_VERBOSE_DEBUG if (net_ratelimit()) wiphy_debug(local->hw.wiphy, "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n", skb_queue_len(&sta->tx_filtered[ac]), !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies); #endif dev_kfree_skb(skb); } static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid) { struct tid_ampdu_tx *tid_tx; tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); if (!tid_tx || !tid_tx->bar_pending) return; tid_tx->bar_pending = false; ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn); } static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb) { struct ieee80211_mgmt *mgmt = (void *) skb->data; struct ieee80211_local *local = sta->local; struct ieee80211_sub_if_data *sdata = sta->sdata; if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) sta->last_rx = jiffies; if (ieee80211_is_data_qos(mgmt->frame_control)) { struct ieee80211_hdr *hdr = (void *) skb->data; u8 *qc = ieee80211_get_qos_ctl(hdr); u16 tid = qc[0] & 0xf; ieee80211_check_pending_bar(sta, hdr->addr1, tid); } if (ieee80211_is_action(mgmt->frame_control) && sdata->vif.type == NL80211_IFTYPE_STATION && mgmt->u.action.category == WLAN_CATEGORY_HT && mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS) { /* * This update looks racy, but isn't -- if we come * here we've definitely got a station that we're * talking to, and on a managed interface that can * only be the AP. And the only other place updating * this variable is before we're associated. */ switch (mgmt->u.action.u.ht_smps.smps_control) { case WLAN_HT_SMPS_CONTROL_DYNAMIC: sta->sdata->u.mgd.ap_smps = IEEE80211_SMPS_DYNAMIC; break; case WLAN_HT_SMPS_CONTROL_STATIC: sta->sdata->u.mgd.ap_smps = IEEE80211_SMPS_STATIC; break; case WLAN_HT_SMPS_CONTROL_DISABLED: default: /* shouldn't happen since we don't send that */ sta->sdata->u.mgd.ap_smps = IEEE80211_SMPS_OFF; break; } ieee80211_queue_work(&local->hw, &local->recalc_smps); } } static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn) { struct tid_ampdu_tx *tid_tx; tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); if (!tid_tx) return; tid_tx->failed_bar_ssn = ssn; tid_tx->bar_pending = true; } static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info) { int len = sizeof(struct ieee80211_radiotap_header); /* IEEE80211_RADIOTAP_RATE rate */ if (info->status.rates[0].idx >= 0 && !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) len += 2; /* IEEE80211_RADIOTAP_TX_FLAGS */ len += 2; /* IEEE80211_RADIOTAP_DATA_RETRIES */ len += 1; /* IEEE80211_TX_RC_MCS */ if (info->status.rates[0].idx >= 0 && info->status.rates[0].flags & IEEE80211_TX_RC_MCS) len += 3; return len; } static void ieee80211_add_tx_radiotap_header(struct ieee80211_supported_band *sband, struct sk_buff *skb, int retry_count, int rtap_len) { struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; struct ieee80211_radiotap_header *rthdr; unsigned char *pos; u16 txflags; rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len); memset(rthdr, 0, rtap_len); rthdr->it_len = cpu_to_le16(rtap_len); rthdr->it_present = cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) | (1 << IEEE80211_RADIOTAP_DATA_RETRIES)); pos = (unsigned char *)(rthdr + 1); /* * XXX: Once radiotap gets the bitmap reset thing the vendor * extensions proposal contains, we can actually report * the whole set of tries we did. */ /* IEEE80211_RADIOTAP_RATE */ if (info->status.rates[0].idx >= 0 && !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) { rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE); *pos = sband->bitrates[info->status.rates[0].idx].bitrate / 5; /* padding for tx flags */ pos += 2; } /* IEEE80211_RADIOTAP_TX_FLAGS */ txflags = 0; if (!(info->flags & IEEE80211_TX_STAT_ACK) && !is_multicast_ether_addr(hdr->addr1)) txflags |= IEEE80211_RADIOTAP_F_TX_FAIL; if ((info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) || (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)) txflags |= IEEE80211_RADIOTAP_F_TX_CTS; else if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) txflags |= IEEE80211_RADIOTAP_F_TX_RTS; put_unaligned_le16(txflags, pos); pos += 2; /* IEEE80211_RADIOTAP_DATA_RETRIES */ /* for now report the total retry_count */ *pos = retry_count; pos++; /* IEEE80211_TX_RC_MCS */ if (info->status.rates[0].idx >= 0 && info->status.rates[0].flags & IEEE80211_TX_RC_MCS) { rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS); pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS | IEEE80211_RADIOTAP_MCS_HAVE_GI | IEEE80211_RADIOTAP_MCS_HAVE_BW; if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI) pos[1] |= IEEE80211_RADIOTAP_MCS_SGI; if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH) pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40; if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD) pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF; pos[2] = info->status.rates[0].idx; pos += 3; } } /* * Use a static threshold for now, best value to be determined * by testing ... * Should it depend on: * - on # of retransmissions * - current throughput (higher value for higher tpt)? */ #define STA_LOST_PKT_THRESHOLD 50 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb) { struct sk_buff *skb2; struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); __le16 fc; struct ieee80211_supported_band *sband; struct ieee80211_sub_if_data *sdata; struct net_device *prev_dev = NULL; struct sta_info *sta, *tmp; int retry_count = -1, i; int rates_idx = -1; bool send_to_cooked; bool acked; struct ieee80211_bar *bar; int rtap_len; for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { if (info->status.rates[i].idx < 0) { break; } else if (i >= hw->max_report_rates) { /* the HW cannot have attempted that rate */ info->status.rates[i].idx = -1; info->status.rates[i].count = 0; break; } retry_count += info->status.rates[i].count; } rates_idx = i - 1; if (retry_count < 0) retry_count = 0; rcu_read_lock(); sband = local->hw.wiphy->bands[info->band]; fc = hdr->frame_control; for_each_sta_info(local, hdr->addr1, sta, tmp) { /* skip wrong virtual interface */ if (compare_ether_addr(hdr->addr2, sta->sdata->vif.addr)) continue; if (info->flags & IEEE80211_TX_STATUS_EOSP) clear_sta_flag(sta, WLAN_STA_SP); acked = !!(info->flags & IEEE80211_TX_STAT_ACK); if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) { /* * The STA is in power save mode, so assume * that this TX packet failed because of that. */ ieee80211_handle_filtered_frame(local, sta, skb); rcu_read_unlock(); return; } if ((local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) && (rates_idx != -1)) sta->last_tx_rate = info->status.rates[rates_idx]; if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) && (ieee80211_is_data_qos(fc))) { u16 tid, ssn; u8 *qc; qc = ieee80211_get_qos_ctl(hdr); tid = qc[0] & 0xf; ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10) & IEEE80211_SCTL_SEQ); ieee80211_send_bar(&sta->sdata->vif, hdr->addr1, tid, ssn); } if (!acked && ieee80211_is_back_req(fc)) { u16 tid, control; /* * BAR failed, store the last SSN and retry sending * the BAR when the next unicast transmission on the * same TID succeeds. */ bar = (struct ieee80211_bar *) skb->data; control = le16_to_cpu(bar->control); if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) { u16 ssn = le16_to_cpu(bar->start_seq_num); tid = (control & IEEE80211_BAR_CTRL_TID_INFO_MASK) >> IEEE80211_BAR_CTRL_TID_INFO_SHIFT; ieee80211_set_bar_pending(sta, tid, ssn); } } if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) { ieee80211_handle_filtered_frame(local, sta, skb); rcu_read_unlock(); return; } else { if (!acked) sta->tx_retry_failed++; sta->tx_retry_count += retry_count; } rate_control_tx_status(local, sband, sta, skb); if (ieee80211_vif_is_mesh(&sta->sdata->vif)) ieee80211s_update_metric(local, sta, skb); if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked) ieee80211_frame_acked(sta, skb); if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) && (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)) ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data, acked); if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) { if (info->flags & IEEE80211_TX_STAT_ACK) { if (sta->lost_packets) sta->lost_packets = 0; } else if (++sta->lost_packets >= STA_LOST_PKT_THRESHOLD) { cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr, sta->lost_packets, GFP_ATOMIC); sta->lost_packets = 0; } } } rcu_read_unlock(); ieee80211_led_tx(local, 0); /* SNMP counters * Fragments are passed to low-level drivers as separate skbs, so these * are actually fragments, not frames. Update frame counters only for * the first fragment of the frame. */ if (info->flags & IEEE80211_TX_STAT_ACK) { if (ieee80211_is_first_frag(hdr->seq_ctrl)) { local->dot11TransmittedFrameCount++; if (is_multicast_ether_addr(hdr->addr1)) local->dot11MulticastTransmittedFrameCount++; if (retry_count > 0) local->dot11RetryCount++; if (retry_count > 1) local->dot11MultipleRetryCount++; } /* This counter shall be incremented for an acknowledged MPDU * with an individual address in the address 1 field or an MPDU * with a multicast address in the address 1 field of type Data * or Management. */ if (!is_multicast_ether_addr(hdr->addr1) || ieee80211_is_data(fc) || ieee80211_is_mgmt(fc)) local->dot11TransmittedFragmentCount++; } else { if (ieee80211_is_first_frag(hdr->seq_ctrl)) local->dot11FailedCount++; } if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) && (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) && !(info->flags & IEEE80211_TX_CTL_INJECTED) && local->ps_sdata && !(local->scanning)) { if (info->flags & IEEE80211_TX_STAT_ACK) { local->ps_sdata->u.mgd.flags |= IEEE80211_STA_NULLFUNC_ACKED; } else mod_timer(&local->dynamic_ps_timer, jiffies + msecs_to_jiffies(10)); } if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) { u64 cookie = (unsigned long)skb; if (ieee80211_is_nullfunc(hdr->frame_control) || ieee80211_is_qos_nullfunc(hdr->frame_control)) { acked = info->flags & IEEE80211_TX_STAT_ACK; cfg80211_probe_status(skb->dev, hdr->addr1, cookie, acked, GFP_ATOMIC); } else { struct ieee80211_work *wk; rcu_read_lock(); list_for_each_entry_rcu(wk, &local->work_list, list) { if (wk->type != IEEE80211_WORK_OFFCHANNEL_TX) continue; if (wk->offchan_tx.frame != skb) continue; wk->offchan_tx.status = true; break; } rcu_read_unlock(); if (local->hw_roc_skb_for_status == skb) { cookie = local->hw_roc_cookie ^ 2; local->hw_roc_skb_for_status = NULL; } cfg80211_mgmt_tx_status( skb->dev, cookie, skb->data, skb->len, !!(info->flags & IEEE80211_TX_STAT_ACK), GFP_ATOMIC); } } if (unlikely(info->ack_frame_id)) { struct sk_buff *ack_skb; unsigned long flags; spin_lock_irqsave(&local->ack_status_lock, flags); ack_skb = idr_find(&local->ack_status_frames, info->ack_frame_id); if (ack_skb) idr_remove(&local->ack_status_frames, info->ack_frame_id); spin_unlock_irqrestore(&local->ack_status_lock, flags); /* consumes ack_skb */ if (ack_skb) skb_complete_wifi_ack(ack_skb, info->flags & IEEE80211_TX_STAT_ACK); } /* this was a transmitted frame, but now we want to reuse it */ skb_orphan(skb); /* Need to make a copy before skb->cb gets cleared */ send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) || !(ieee80211_is_data(fc)); /* * This is a bit racy but we can avoid a lot of work * with this test... */ if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) { dev_kfree_skb(skb); return; } /* send frame to monitor interfaces now */ rtap_len = ieee80211_tx_radiotap_len(info); if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) { printk(KERN_ERR "ieee80211_tx_status: headroom too small\n"); dev_kfree_skb(skb); return; } ieee80211_add_tx_radiotap_header(sband, skb, retry_count, rtap_len); /* XXX: is this sufficient for BPF? */ skb_set_mac_header(skb, 0); skb->ip_summed = CHECKSUM_UNNECESSARY; skb->pkt_type = PACKET_OTHERHOST; skb->protocol = htons(ETH_P_802_2); memset(skb->cb, 0, sizeof(skb->cb)); rcu_read_lock(); list_for_each_entry_rcu(sdata, &local->interfaces, list) { if (sdata->vif.type == NL80211_IFTYPE_MONITOR) { if (!ieee80211_sdata_running(sdata)) continue; if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) && !send_to_cooked) continue; if (prev_dev) { skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) { skb2->dev = prev_dev; netif_rx(skb2); } } prev_dev = sdata->dev; } } if (prev_dev) { skb->dev = prev_dev; netif_rx(skb); skb = NULL; } rcu_read_unlock(); dev_kfree_skb(skb); } EXPORT_SYMBOL(ieee80211_tx_status); void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets) { struct sta_info *sta = container_of(pubsta, struct sta_info, sta); cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr, num_packets, GFP_ATOMIC); } EXPORT_SYMBOL(ieee80211_report_low_ack); void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb) { struct ieee80211_local *local = hw_to_local(hw); struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); if (unlikely(info->ack_frame_id)) { struct sk_buff *ack_skb; unsigned long flags; spin_lock_irqsave(&local->ack_status_lock, flags); ack_skb = idr_find(&local->ack_status_frames, info->ack_frame_id); if (ack_skb) idr_remove(&local->ack_status_frames, info->ack_frame_id); spin_unlock_irqrestore(&local->ack_status_lock, flags); /* consumes ack_skb */ if (ack_skb) dev_kfree_skb_any(ack_skb); } dev_kfree_skb_any(skb); } EXPORT_SYMBOL(ieee80211_free_txskb); void ieee80211_purge_tx_queue(struct ieee80211_hw *hw, struct sk_buff_head *skbs) { struct sk_buff *skb; while ((skb = __skb_dequeue(skbs))) ieee80211_free_txskb(hw, skb); }