/** * mesh_path_error_tx - Sends a PERR mesh management frame * * @ttl: allowed remaining hops * @target: broken destination * @target_sn: SN of the broken destination * @target_rcode: reason code for this PERR * @ra: node this frame is addressed to * @sdata: local mesh subif * * Note: This function may be called with driver locks taken that the driver * also acquires in the TX path. To avoid a deadlock we don't transmit the * frame directly but add it to the pending queue instead. */ int mesh_path_error_tx(struct ieee80211_sub_if_data *sdata, u8 ttl, const u8 *target, u32 target_sn, u16 target_rcode, const u8 *ra) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; struct ieee80211_mgmt *mgmt; u8 *pos, ie_len; int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + sizeof(mgmt->u.action.u.mesh_action); if (time_before(jiffies, ifmsh->next_perr)) return -EAGAIN; skb = dev_alloc_skb(local->tx_headroom + sdata->encrypt_headroom + IEEE80211_ENCRYPT_TAILROOM + hdr_len + 2 + 15 /* PERR IE */); if (!skb) return -1; skb_reserve(skb, local->tx_headroom + sdata->encrypt_headroom); mgmt = skb_put_zero(skb, hdr_len); mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_ACTION); memcpy(mgmt->da, ra, ETH_ALEN); memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); /* BSSID == SA */ memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; mgmt->u.action.u.mesh_action.action_code = WLAN_MESH_ACTION_HWMP_PATH_SELECTION; ie_len = 15; pos = skb_put(skb, 2 + ie_len); *pos++ = WLAN_EID_PERR; *pos++ = ie_len; /* ttl */ *pos++ = ttl; /* number of destinations */ *pos++ = 1; /* Flags field has AE bit only as defined in * sec 8.4.2.117 IEEE802.11-2012 */ *pos = 0; pos++; memcpy(pos, target, ETH_ALEN); pos += ETH_ALEN; put_unaligned_le32(target_sn, pos); pos += 4; put_unaligned_le16(target_rcode, pos); /* see note in function header */ prepare_frame_for_deferred_tx(sdata, skb); ifmsh->next_perr = TU_TO_EXP_TIME( ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); ieee80211_add_pending_skb(local, skb); return 0; }
/** * hwmp_route_info_get - Update routing info to originator and transmitter * * @sdata: local mesh subif * @mgmt: mesh management frame * @hwmp_ie: hwmp information element (PREP or PREQ) * * This function updates the path routing information to the originator and the * transmitter of a HWMP PREQ or PREP fram. * * Returns: metric to frame originator or 0 if the frame should not be further * processed * * Notes: this function is the only place (besides user-provided info) where * path routing information is updated. */ static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, u8 *hwmp_ie) { struct ieee80211_local *local = sdata->local; struct mesh_path *mpath; struct sta_info *sta; bool fresh_info; u8 *orig_addr, *ta; u32 orig_dsn, orig_metric; unsigned long orig_lifetime, exp_time; u32 last_hop_metric, new_metric; bool process = true; u8 action = mgmt->u.action.u.mesh_action.action_code; rcu_read_lock(); sta = sta_info_get(local, mgmt->sa); if (!sta) { rcu_read_unlock(); return 0; } last_hop_metric = airtime_link_metric_get(local, sta); /* Update and check originator routing info */ fresh_info = true; switch (action) { case MPATH_PREQ: orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); orig_dsn = PREQ_IE_ORIG_DSN(hwmp_ie); orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); orig_metric = PREQ_IE_METRIC(hwmp_ie); break; case MPATH_PREP: /* Originator here refers to the MP that was the destination in * the Path Request. The draft refers to that MP as the * destination address, even though usually it is the origin of * the PREP frame. We divert from the nomenclature in the draft * so that we can easily use a single function to gather path * information from both PREQ and PREP frames. */ orig_addr = PREP_IE_ORIG_ADDR(hwmp_ie); orig_dsn = PREP_IE_ORIG_DSN(hwmp_ie); orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); orig_metric = PREP_IE_METRIC(hwmp_ie); break; default: rcu_read_unlock(); return 0; } new_metric = orig_metric + last_hop_metric; if (new_metric < orig_metric) new_metric = MAX_METRIC; exp_time = TU_TO_EXP_TIME(orig_lifetime); if (memcmp(orig_addr, sdata->dev->dev_addr, ETH_ALEN) == 0) { /* This MP is the originator, we are not interested in this * frame, except for updating transmitter's path info. */ process = false; fresh_info = false; } else { mpath = mesh_path_lookup(orig_addr, sdata); if (mpath) { spin_lock_bh(&mpath->state_lock); if (mpath->flags & MESH_PATH_FIXED) fresh_info = false; else if ((mpath->flags & MESH_PATH_ACTIVE) && (mpath->flags & MESH_PATH_DSN_VALID)) { if (DSN_GT(mpath->dsn, orig_dsn) || (mpath->dsn == orig_dsn && action == MPATH_PREQ && new_metric > mpath->metric)) { process = false; fresh_info = false; } } } else { mesh_path_add(orig_addr, sdata); mpath = mesh_path_lookup(orig_addr, sdata); if (!mpath) { rcu_read_unlock(); return 0; } spin_lock_bh(&mpath->state_lock); } if (fresh_info) { mesh_path_assign_nexthop(mpath, sta); mpath->flags |= MESH_PATH_DSN_VALID; mpath->metric = new_metric; mpath->dsn = orig_dsn; mpath->exp_time = time_after(mpath->exp_time, exp_time) ? mpath->exp_time : exp_time; mesh_path_activate(mpath); spin_unlock_bh(&mpath->state_lock); mesh_path_tx_pending(mpath); /* draft says preq_id should be saved to, but there does * not seem to be any use for it, skipping by now */ } else spin_unlock_bh(&mpath->state_lock); } /* Update and check transmitter routing info */ ta = mgmt->sa; if (memcmp(orig_addr, ta, ETH_ALEN) == 0) fresh_info = false; else { fresh_info = true; mpath = mesh_path_lookup(ta, sdata); if (mpath) { spin_lock_bh(&mpath->state_lock); if ((mpath->flags & MESH_PATH_FIXED) || ((mpath->flags & MESH_PATH_ACTIVE) && (last_hop_metric > mpath->metric))) fresh_info = false; } else { mesh_path_add(ta, sdata); mpath = mesh_path_lookup(ta, sdata); if (!mpath) { rcu_read_unlock(); return 0; } spin_lock_bh(&mpath->state_lock); } if (fresh_info) { mesh_path_assign_nexthop(mpath, sta); mpath->flags &= ~MESH_PATH_DSN_VALID; mpath->metric = last_hop_metric; mpath->exp_time = time_after(mpath->exp_time, exp_time) ? mpath->exp_time : exp_time; mesh_path_activate(mpath); spin_unlock_bh(&mpath->state_lock); mesh_path_tx_pending(mpath); } else spin_unlock_bh(&mpath->state_lock); } rcu_read_unlock(); return process ? new_metric : 0; }
void ieee80211_process_addba_resp(struct ieee80211_local *local, struct sta_info *sta, struct ieee80211_mgmt *mgmt, size_t len) { struct tid_ampdu_tx *tid_tx; u16 capab, tid; u8 buf_size; capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab); tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; mutex_lock(&sta->ampdu_mlme.mtx); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) goto out; if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) { #ifdef CONFIG_MAC80211_HT_DEBUG printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid); #endif goto out; } del_timer_sync(&tid_tx->addba_resp_timer); #ifdef CONFIG_MAC80211_HT_DEBUG printk(KERN_DEBUG "switched off addBA timer for tid %d\n", tid); #endif /* * addba_resp_timer may have fired before we got here, and * caused WANT_STOP to be set. If the stop then was already * processed further, STOPPING might be set. */ if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { #ifdef CONFIG_MAC80211_HT_DEBUG printk(KERN_DEBUG "got addBA resp for tid %d but we already gave up\n", tid); #endif goto out; } /* * IEEE 802.11-2007 7.3.1.14: * In an ADDBA Response frame, when the Status Code field * is set to 0, the Buffer Size subfield is set to a value * of at least 1. */ if (le16_to_cpu(mgmt->u.action.u.addba_resp.status) == WLAN_STATUS_SUCCESS && buf_size) { if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { /* ignore duplicate response */ goto out; } tid_tx->buf_size = buf_size; if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)) ieee80211_agg_tx_operational(local, sta, tid); sta->ampdu_mlme.addba_req_num[tid] = 0; if (tid_tx->timeout) { mod_timer(&tid_tx->session_timer, TU_TO_EXP_TIME(tid_tx->timeout)); tid_tx->last_tx = jiffies; } } else { ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR, true); } out: mutex_unlock(&sta->ampdu_mlme.mtx); }
/** * mesh_path_error_tx - Sends a PERR mesh management frame * * @ttl: allowed remaining hops * @target: broken destination * @target_sn: SN of the broken destination * @target_rcode: reason code for this PERR * @ra: node this frame is addressed to * @sdata: local mesh subif * * Note: This function may be called with driver locks taken that the driver * also acquires in the TX path. To avoid a deadlock we don't transmit the * frame directly but add it to the pending queue instead. */ int mesh_path_error_tx(u8 ttl, u8 *target, __le32 target_sn, __le16 target_rcode, const u8 *ra, struct ieee80211_sub_if_data *sdata) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; struct ieee80211_mgmt *mgmt; u8 *pos, ie_len; int hdr_len = offsetof(struct ieee80211_mgmt, u.action.u.mesh_action) + sizeof(mgmt->u.action.u.mesh_action); if (time_before(jiffies, ifmsh->next_perr)) return -EAGAIN; skb = dev_alloc_skb(local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM + IEEE80211_ENCRYPT_TAILROOM + hdr_len + 2 + 15 /* PERR IE */); if (!skb) return -1; skb_reserve(skb, local->tx_headroom + IEEE80211_ENCRYPT_HEADROOM); mgmt = (struct ieee80211_mgmt *) skb_put(skb, hdr_len); memset(mgmt, 0, hdr_len); mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_ACTION); memcpy(mgmt->da, ra, ETH_ALEN); memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); /* BSSID == SA */ memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); mgmt->u.action.category = WLAN_CATEGORY_MESH_ACTION; mgmt->u.action.u.mesh_action.action_code = WLAN_MESH_ACTION_HWMP_PATH_SELECTION; ie_len = 15; pos = skb_put(skb, 2 + ie_len); *pos++ = WLAN_EID_PERR; *pos++ = ie_len; /* ttl */ *pos++ = ttl; /* number of destinations */ *pos++ = 1; /* * flags bit, bit 1 is unset if we know the sequence number and * bit 2 is set if we have a reason code */ *pos = 0; if (!target_sn) *pos |= MP_F_USN; if (target_rcode) *pos |= MP_F_RCODE; pos++; memcpy(pos, target, ETH_ALEN); pos += ETH_ALEN; memcpy(pos, &target_sn, 4); pos += 4; memcpy(pos, &target_rcode, 2); /* see note in function header */ prepare_frame_for_deferred_tx(sdata, skb); ifmsh->next_perr = TU_TO_EXP_TIME( ifmsh->mshcfg.dot11MeshHWMPperrMinInterval); ieee80211_add_pending_skb(local, skb); return 0; }
/** * hwmp_route_info_get - Update routing info to originator and transmitter * * @sdata: local mesh subif * @mgmt: mesh management frame * @hwmp_ie: hwmp information element (PREP or PREQ) * @action: type of hwmp ie * * This function updates the path routing information to the originator and the * transmitter of a HWMP PREQ or PREP frame. * * Returns: metric to frame originator or 0 if the frame should not be further * processed * * Notes: this function is the only place (besides user-provided info) where * path routing information is updated. */ static u32 hwmp_route_info_get(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, const u8 *hwmp_ie, enum mpath_frame_type action) { struct ieee80211_local *local = sdata->local; struct mesh_path *mpath; struct sta_info *sta; bool fresh_info; const u8 *orig_addr, *ta; u32 orig_sn, orig_metric; unsigned long orig_lifetime, exp_time; u32 last_hop_metric, new_metric; bool process = true; rcu_read_lock(); sta = sta_info_get(sdata, mgmt->sa); if (!sta) { rcu_read_unlock(); return 0; } last_hop_metric = airtime_link_metric_get(local, sta); /* Update and check originator routing info */ fresh_info = true; switch (action) { case MPATH_PREQ: orig_addr = PREQ_IE_ORIG_ADDR(hwmp_ie); orig_sn = PREQ_IE_ORIG_SN(hwmp_ie); orig_lifetime = PREQ_IE_LIFETIME(hwmp_ie); orig_metric = PREQ_IE_METRIC(hwmp_ie); break; case MPATH_PREP: /* Originator here refers to the MP that was the target in the * Path Request. We divert from the nomenclature in the draft * so that we can easily use a single function to gather path * information from both PREQ and PREP frames. */ orig_addr = PREP_IE_TARGET_ADDR(hwmp_ie); orig_sn = PREP_IE_TARGET_SN(hwmp_ie); orig_lifetime = PREP_IE_LIFETIME(hwmp_ie); orig_metric = PREP_IE_METRIC(hwmp_ie); break; default: rcu_read_unlock(); return 0; } new_metric = orig_metric + last_hop_metric; if (new_metric < orig_metric) new_metric = MAX_METRIC; exp_time = TU_TO_EXP_TIME(orig_lifetime); if (ether_addr_equal(orig_addr, sdata->vif.addr)) { /* This MP is the originator, we are not interested in this * frame, except for updating transmitter's path info. */ process = false; fresh_info = false; } else { mpath = mesh_path_lookup(sdata, orig_addr); if (mpath) { spin_lock_bh(&mpath->state_lock); if (mpath->flags & MESH_PATH_FIXED) fresh_info = false; else if ((mpath->flags & MESH_PATH_ACTIVE) && (mpath->flags & MESH_PATH_SN_VALID)) { if (SN_GT(mpath->sn, orig_sn) || (mpath->sn == orig_sn && new_metric >= mpath->metric)) { process = false; fresh_info = false; } } else if (!(mpath->flags & MESH_PATH_ACTIVE)) { bool have_sn, newer_sn, bounced; have_sn = mpath->flags & MESH_PATH_SN_VALID; newer_sn = have_sn && SN_GT(orig_sn, mpath->sn); bounced = have_sn && (SN_DELTA(orig_sn, mpath->sn) > MAX_SANE_SN_DELTA); if (!have_sn || newer_sn) { /* if SN is newer than what we had * then we can take it */; } else if (bounced) { /* if SN is way different than what * we had then assume the other side * rebooted or restarted */; } else { process = false; fresh_info = false; } } } else { mpath = mesh_path_add(sdata, orig_addr); if (IS_ERR(mpath)) { rcu_read_unlock(); return 0; } spin_lock_bh(&mpath->state_lock); } if (fresh_info) { mesh_path_assign_nexthop(mpath, sta); mpath->flags |= MESH_PATH_SN_VALID; mpath->metric = new_metric; mpath->sn = orig_sn; mpath->exp_time = time_after(mpath->exp_time, exp_time) ? mpath->exp_time : exp_time; mesh_path_activate(mpath); spin_unlock_bh(&mpath->state_lock); ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); /* init it at a low value - 0 start is tricky */ ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); mesh_path_tx_pending(mpath); /* draft says preq_id should be saved to, but there does * not seem to be any use for it, skipping by now */ } else spin_unlock_bh(&mpath->state_lock); } /* Update and check transmitter routing info */ ta = mgmt->sa; if (ether_addr_equal(orig_addr, ta)) fresh_info = false; else { fresh_info = true; mpath = mesh_path_lookup(sdata, ta); if (mpath) { spin_lock_bh(&mpath->state_lock); if ((mpath->flags & MESH_PATH_FIXED) || ((mpath->flags & MESH_PATH_ACTIVE) && (last_hop_metric > mpath->metric))) fresh_info = false; } else { mpath = mesh_path_add(sdata, ta); if (IS_ERR(mpath)) { rcu_read_unlock(); return 0; } spin_lock_bh(&mpath->state_lock); } if (fresh_info) { mesh_path_assign_nexthop(mpath, sta); mpath->metric = last_hop_metric; mpath->exp_time = time_after(mpath->exp_time, exp_time) ? mpath->exp_time : exp_time; mesh_path_activate(mpath); spin_unlock_bh(&mpath->state_lock); ewma_mesh_fail_avg_init(&sta->mesh->fail_avg); /* init it at a low value - 0 start is tricky */ ewma_mesh_fail_avg_add(&sta->mesh->fail_avg, 1); mesh_path_tx_pending(mpath); } else spin_unlock_bh(&mpath->state_lock); } rcu_read_unlock(); return process ? new_metric : 0; }
int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, enum ieee80211_agg_stop_reason reason) { struct ieee80211_local *local = sta->local; struct tid_ampdu_tx *tid_tx; struct ieee80211_ampdu_params params = { .sta = &sta->sta, .tid = tid, .buf_size = 0, .amsdu = false, .timeout = 0, .ssn = 0, }; int ret; lockdep_assert_held(&sta->ampdu_mlme.mtx); switch (reason) { case AGG_STOP_DECLINED: case AGG_STOP_LOCAL_REQUEST: case AGG_STOP_PEER_REQUEST: params.action = IEEE80211_AMPDU_TX_STOP_CONT; break; case AGG_STOP_DESTROY_STA: params.action = IEEE80211_AMPDU_TX_STOP_FLUSH; break; default: WARN_ON_ONCE(1); return -EINVAL; } spin_lock_bh(&sta->lock); /* free struct pending for start, if present */ tid_tx = sta->ampdu_mlme.tid_start_tx[tid]; kfree(tid_tx); sta->ampdu_mlme.tid_start_tx[tid] = NULL; tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) { spin_unlock_bh(&sta->lock); return -ENOENT; } /* * if we're already stopping ignore any new requests to stop * unless we're destroying it in which case notify the driver */ if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { spin_unlock_bh(&sta->lock); if (reason != AGG_STOP_DESTROY_STA) return -EALREADY; params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT; ret = drv_ampdu_action(local, sta->sdata, ¶ms); WARN_ON_ONCE(ret); return 0; } if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) { /* not even started yet! */ ieee80211_assign_tid_tx(sta, tid, NULL); spin_unlock_bh(&sta->lock); kfree_rcu(tid_tx, rcu_head); return 0; } set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state); spin_unlock_bh(&sta->lock); ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n", sta->sta.addr, tid); del_timer_sync(&tid_tx->addba_resp_timer); del_timer_sync(&tid_tx->session_timer); /* * After this packets are no longer handed right through * to the driver but are put onto tid_tx->pending instead, * with locking to ensure proper access. */ clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); /* * There might be a few packets being processed right now (on * another CPU) that have already gotten past the aggregation * check when it was still OPERATIONAL and consequently have * IEEE80211_TX_CTL_AMPDU set. In that case, this code might * call into the driver at the same time or even before the * TX paths calls into it, which could confuse the driver. * * Wait for all currently running TX paths to finish before * telling the driver. New packets will not go through since * the aggregation session is no longer OPERATIONAL. */ synchronize_net(); tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ? WLAN_BACK_RECIPIENT : WLAN_BACK_INITIATOR; tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST; ret = drv_ampdu_action(local, sta->sdata, ¶ms); /* HW shall not deny going back to legacy */ if (WARN_ON(ret)) { /* * We may have pending packets get stuck in this case... * Not bothering with a workaround for now. */ } /* * In the case of AGG_STOP_DESTROY_STA, the driver won't * necessarily call ieee80211_stop_tx_ba_cb(), so this may * seem like we can leave the tid_tx data pending forever. * This is true, in a way, but "forever" is only until the * station struct is actually destroyed. In the meantime, * leaving it around ensures that we don't transmit packets * to the driver on this TID which might confuse it. */ return 0; } /* * After sending add Block Ack request we activated a timer until * add Block Ack response will arrive from the recipient. * If this timer expires sta_addba_resp_timer_expired will be executed. */ static void sta_addba_resp_timer_expired(struct timer_list *t) { struct tid_ampdu_tx *tid_tx_timer = from_timer(tid_tx_timer, t, addba_resp_timer); struct sta_info *sta = tid_tx_timer->sta; u8 tid = tid_tx_timer->tid; struct tid_ampdu_tx *tid_tx; /* check if the TID waits for addBA response */ rcu_read_lock(); tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); if (!tid_tx || test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { rcu_read_unlock(); ht_dbg(sta->sdata, "timer expired on %pM tid %d not expecting addBA response\n", sta->sta.addr, tid); return; } ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n", sta->sta.addr, tid); ieee80211_stop_tx_ba_session(&sta->sta, tid); rcu_read_unlock(); } void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid) { struct tid_ampdu_tx *tid_tx; struct ieee80211_local *local = sta->local; struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_ampdu_params params = { .sta = &sta->sta, .action = IEEE80211_AMPDU_TX_START, .tid = tid, .buf_size = 0, .amsdu = false, .timeout = 0, }; int ret; tid_tx = rcu_dereference_protected_tid_tx(sta, tid); /* * Start queuing up packets for this aggregation session. * We're going to release them once the driver is OK with * that. */ clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); ieee80211_agg_stop_txq(sta, tid); /* * Make sure no packets are being processed. This ensures that * we have a valid starting sequence number and that in-flight * packets have been flushed out and no packets for this TID * will go into the driver during the ampdu_action call. */ synchronize_net(); params.ssn = sta->tid_seq[tid] >> 4; ret = drv_ampdu_action(local, sdata, ¶ms); if (ret) { ht_dbg(sdata, "BA request denied - HW unavailable for %pM tid %d\n", sta->sta.addr, tid); spin_lock_bh(&sta->lock); ieee80211_agg_splice_packets(sdata, tid_tx, tid); ieee80211_assign_tid_tx(sta, tid, NULL); ieee80211_agg_splice_finish(sdata, tid); spin_unlock_bh(&sta->lock); ieee80211_agg_start_txq(sta, tid, false); kfree_rcu(tid_tx, rcu_head); return; } /* activate the timer for the recipient's addBA response */ mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL); ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n", sta->sta.addr, tid); spin_lock_bh(&sta->lock); sta->ampdu_mlme.last_addba_req_time[tid] = jiffies; sta->ampdu_mlme.addba_req_num[tid]++; spin_unlock_bh(&sta->lock); /* send AddBA request */ ieee80211_send_addba_request(sdata, sta->sta.addr, tid, tid_tx->dialog_token, params.ssn, IEEE80211_MAX_AMPDU_BUF, tid_tx->timeout); } /* * After accepting the AddBA Response we activated a timer, * resetting it after each frame that we send. */ static void sta_tx_agg_session_timer_expired(struct timer_list *t) { struct tid_ampdu_tx *tid_tx_timer = from_timer(tid_tx_timer, t, session_timer); struct sta_info *sta = tid_tx_timer->sta; u8 tid = tid_tx_timer->tid; struct tid_ampdu_tx *tid_tx; unsigned long timeout; rcu_read_lock(); tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { rcu_read_unlock(); return; } timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); if (time_is_after_jiffies(timeout)) { mod_timer(&tid_tx->session_timer, timeout); rcu_read_unlock(); return; } rcu_read_unlock(); ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n", sta->sta.addr, tid); ieee80211_stop_tx_ba_session(&sta->sta, tid); } int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid, u16 timeout) { struct sta_info *sta = container_of(pubsta, struct sta_info, sta); struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_local *local = sdata->local; struct tid_ampdu_tx *tid_tx; int ret = 0; trace_api_start_tx_ba_session(pubsta, tid); if (WARN(sta->reserved_tid == tid, "Requested to start BA session on reserved tid=%d", tid)) return -EINVAL; if (!pubsta->ht_cap.ht_supported) return -EINVAL; if (WARN_ON_ONCE(!local->ops->ampdu_action)) return -EINVAL; if ((tid >= IEEE80211_NUM_TIDS) || !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) || ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW)) return -EINVAL; if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID)) return -EINVAL; ht_dbg(sdata, "Open BA session requested for %pM tid %u\n", pubsta->addr, tid); if (sdata->vif.type != NL80211_IFTYPE_STATION && sdata->vif.type != NL80211_IFTYPE_MESH_POINT && sdata->vif.type != NL80211_IFTYPE_AP_VLAN && sdata->vif.type != NL80211_IFTYPE_AP && sdata->vif.type != NL80211_IFTYPE_ADHOC) return -EINVAL; if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { ht_dbg(sdata, "BA sessions blocked - Denying BA session request %pM tid %d\n", sta->sta.addr, tid); return -EINVAL; } /* * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a * member of an IBSS, and has no other existing Block Ack agreement * with the recipient STA, then the initiating STA shall transmit a * Probe Request frame to the recipient STA and shall not transmit an * ADDBA Request frame unless it receives a Probe Response frame * from the recipient within dot11ADDBAFailureTimeout. * * The probe request mechanism for ADDBA is currently not implemented, * but we only build up Block Ack session with HT STAs. This information * is set when we receive a bss info from a probe response or a beacon. */ if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC && !sta->sta.ht_cap.ht_supported) { ht_dbg(sdata, "BA request denied - IBSS STA %pM does not advertise HT support\n", pubsta->addr); return -EINVAL; } spin_lock_bh(&sta->lock); /* we have tried too many times, receiver does not want A-MPDU */ if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) { ret = -EBUSY; goto err_unlock_sta; } /* * if we have tried more than HT_AGG_BURST_RETRIES times we * will spread our requests in time to avoid stalling connection * for too long */ if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES && time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] + HT_AGG_RETRIES_PERIOD)) { ht_dbg(sdata, "BA request denied - %d failed requests on %pM tid %u\n", sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid); ret = -EBUSY; goto err_unlock_sta; } tid_tx = rcu_dereference_protected_tid_tx(sta, tid); /* check if the TID is not in aggregation flow already */ if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) { ht_dbg(sdata, "BA request denied - session is not idle on %pM tid %u\n", sta->sta.addr, tid); ret = -EAGAIN; goto err_unlock_sta; } /* prepare A-MPDU MLME for Tx aggregation */ tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC); if (!tid_tx) { ret = -ENOMEM; goto err_unlock_sta; } skb_queue_head_init(&tid_tx->pending); __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); tid_tx->timeout = timeout; tid_tx->sta = sta; tid_tx->tid = tid; /* response timer */ timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0); /* tx timer */ timer_setup(&tid_tx->session_timer, sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE); /* assign a dialog token */ sta->ampdu_mlme.dialog_token_allocator++; tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator; /* * Finally, assign it to the start array; the work item will * collect it and move it to the normal array. */ sta->ampdu_mlme.tid_start_tx[tid] = tid_tx; ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); /* this flow continues off the work */ err_unlock_sta: spin_unlock_bh(&sta->lock); return ret; } EXPORT_SYMBOL(ieee80211_start_tx_ba_session); static void ieee80211_agg_tx_operational(struct ieee80211_local *local, struct sta_info *sta, u16 tid) { struct tid_ampdu_tx *tid_tx; struct ieee80211_ampdu_params params = { .sta = &sta->sta, .action = IEEE80211_AMPDU_TX_OPERATIONAL, .tid = tid, .timeout = 0, .ssn = 0, }; lockdep_assert_held(&sta->ampdu_mlme.mtx); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); params.buf_size = tid_tx->buf_size; params.amsdu = tid_tx->amsdu; ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n", sta->sta.addr, tid); drv_ampdu_action(local, sta->sdata, ¶ms); /* * synchronize with TX path, while splicing the TX path * should block so it won't put more packets onto pending. */ spin_lock_bh(&sta->lock); ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); /* * Now mark as operational. This will be visible * in the TX path, and lets it go lock-free in * the common case. */ set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); ieee80211_agg_splice_finish(sta->sdata, tid); spin_unlock_bh(&sta->lock); ieee80211_agg_start_txq(sta, tid, true); } void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid, struct tid_ampdu_tx *tid_tx) { struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_local *local = sdata->local; if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))) return; if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) ieee80211_agg_tx_operational(local, sta, tid); } static struct tid_ampdu_tx * ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata, const u8 *ra, u16 tid, struct sta_info **sta) { struct tid_ampdu_tx *tid_tx; if (tid >= IEEE80211_NUM_TIDS) { ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n", tid, IEEE80211_NUM_TIDS); return NULL; } *sta = sta_info_get_bss(sdata, ra); if (!*sta) { ht_dbg(sdata, "Could not find station: %pM\n", ra); return NULL; } tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]); if (WARN_ON(!tid_tx)) ht_dbg(sdata, "addBA was not requested!\n"); return tid_tx; } void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, const u8 *ra, u16 tid) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct sta_info *sta; struct tid_ampdu_tx *tid_tx; trace_api_start_tx_ba_cb(sdata, ra, tid); rcu_read_lock(); tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); if (!tid_tx) goto out; set_bit(HT_AGG_STATE_START_CB, &tid_tx->state); ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); out: rcu_read_unlock(); } EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe); int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, enum ieee80211_agg_stop_reason reason) { int ret; mutex_lock(&sta->ampdu_mlme.mtx); ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason); mutex_unlock(&sta->ampdu_mlme.mtx); return ret; } int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid) { struct sta_info *sta = container_of(pubsta, struct sta_info, sta); struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_local *local = sdata->local; struct tid_ampdu_tx *tid_tx; int ret = 0; trace_api_stop_tx_ba_session(pubsta, tid); if (!local->ops->ampdu_action) return -EINVAL; if (tid >= IEEE80211_NUM_TIDS) return -EINVAL; spin_lock_bh(&sta->lock); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) { ret = -ENOENT; goto unlock; } WARN(sta->reserved_tid == tid, "Requested to stop BA session on reserved tid=%d", tid); if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { /* already in progress stopping it */ ret = 0; goto unlock; } set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state); ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); unlock: spin_unlock_bh(&sta->lock); return ret; } EXPORT_SYMBOL(ieee80211_stop_tx_ba_session); void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid, struct tid_ampdu_tx *tid_tx) { struct ieee80211_sub_if_data *sdata = sta->sdata; bool send_delba = false; ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n", sta->sta.addr, tid); spin_lock_bh(&sta->lock); if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { ht_dbg(sdata, "unexpected callback to A-MPDU stop for %pM tid %d\n", sta->sta.addr, tid); goto unlock_sta; } if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop) send_delba = true; ieee80211_remove_tid_tx(sta, tid); unlock_sta: spin_unlock_bh(&sta->lock); if (send_delba) ieee80211_send_delba(sdata, sta->sta.addr, tid, WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE); } void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, const u8 *ra, u16 tid) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct sta_info *sta; struct tid_ampdu_tx *tid_tx; trace_api_stop_tx_ba_cb(sdata, ra, tid); rcu_read_lock(); tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); if (!tid_tx) goto out; set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state); ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); out: rcu_read_unlock(); } EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe); void ieee80211_process_addba_resp(struct ieee80211_local *local, struct sta_info *sta, struct ieee80211_mgmt *mgmt, size_t len) { struct tid_ampdu_tx *tid_tx; struct ieee80211_txq *txq; u16 capab, tid; u8 buf_size; bool amsdu; capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab); amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK; tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes); txq = sta->sta.txq[tid]; if (!amsdu && txq) set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags); mutex_lock(&sta->ampdu_mlme.mtx); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) goto out; if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) { ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n", sta->sta.addr, tid); goto out; } del_timer_sync(&tid_tx->addba_resp_timer); ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n", sta->sta.addr, tid); /* * addba_resp_timer may have fired before we got here, and * caused WANT_STOP to be set. If the stop then was already * processed further, STOPPING might be set. */ if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { ht_dbg(sta->sdata, "got addBA resp for %pM tid %d but we already gave up\n", sta->sta.addr, tid); goto out; } /* * IEEE 802.11-2007 7.3.1.14: * In an ADDBA Response frame, when the Status Code field * is set to 0, the Buffer Size subfield is set to a value * of at least 1. */ if (le16_to_cpu(mgmt->u.action.u.addba_resp.status) == WLAN_STATUS_SUCCESS && buf_size) { if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { /* ignore duplicate response */ goto out; } tid_tx->buf_size = buf_size; tid_tx->amsdu = amsdu; if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)) ieee80211_agg_tx_operational(local, sta, tid); sta->ampdu_mlme.addba_req_num[tid] = 0; if (tid_tx->timeout) { mod_timer(&tid_tx->session_timer, TU_TO_EXP_TIME(tid_tx->timeout)); tid_tx->last_tx = jiffies; } } else { ___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED); } out: mutex_unlock(&sta->ampdu_mlme.mtx); }
void ieee80211_process_addba_resp(struct ieee80211_local *local, struct sta_info *sta, struct ieee80211_mgmt *mgmt, size_t len) { struct tid_ampdu_tx *tid_tx; struct ieee80211_txq *txq; u16 capab, tid; u8 buf_size; bool amsdu; capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab); amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK; tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes); txq = sta->sta.txq[tid]; if (!amsdu && txq) set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags); mutex_lock(&sta->ampdu_mlme.mtx); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) goto out; if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) { ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n", sta->sta.addr, tid); goto out; } del_timer_sync(&tid_tx->addba_resp_timer); ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n", sta->sta.addr, tid); /* * addba_resp_timer may have fired before we got here, and * caused WANT_STOP to be set. If the stop then was already * processed further, STOPPING might be set. */ if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { ht_dbg(sta->sdata, "got addBA resp for %pM tid %d but we already gave up\n", sta->sta.addr, tid); goto out; } /* * IEEE 802.11-2007 7.3.1.14: * In an ADDBA Response frame, when the Status Code field * is set to 0, the Buffer Size subfield is set to a value * of at least 1. */ if (le16_to_cpu(mgmt->u.action.u.addba_resp.status) == WLAN_STATUS_SUCCESS && buf_size) { if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { /* ignore duplicate response */ goto out; } tid_tx->buf_size = buf_size; tid_tx->amsdu = amsdu; if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)) ieee80211_agg_tx_operational(local, sta, tid); sta->ampdu_mlme.addba_req_num[tid] = 0; if (tid_tx->timeout) { mod_timer(&tid_tx->session_timer, TU_TO_EXP_TIME(tid_tx->timeout)); tid_tx->last_tx = jiffies; } } else { ___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED); } out: mutex_unlock(&sta->ampdu_mlme.mtx); }