Exemplo n.º 1
0
static ssize_t sta_flags_read(struct file *file, char __user *userbuf,
			      size_t count, loff_t *ppos)
{
	char buf[16 * NUM_WLAN_STA_FLAGS], *pos = buf;
	char *end = buf + sizeof(buf) - 1;
	struct sta_info *sta = file->private_data;
	unsigned int flg;

	BUILD_BUG_ON(ARRAY_SIZE(sta_flag_names) != NUM_WLAN_STA_FLAGS);

	for (flg = 0; flg < NUM_WLAN_STA_FLAGS; flg++) {
		if (test_sta_flag(sta, flg))
			pos += scnprintf(pos, end - pos, "%s\n",
					 sta_flag_names[flg]);
	}

	return simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
}
int mesh_plink_open(struct sta_info *sta)
{
	__le16 llid;
	struct ieee80211_sub_if_data *sdata = sta->sdata;

	if (!test_sta_flag(sta, WLAN_STA_AUTH))
		return -EPERM;

	spin_lock_bh(&sta->lock);
	get_random_bytes(&llid, 2);
	sta->llid = llid;
	if (sta->plink_state != NL80211_PLINK_LISTEN) {
		spin_unlock_bh(&sta->lock);
		return -EBUSY;
	}
	sta->plink_state = NL80211_PLINK_OPN_SNT;
	mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
	spin_unlock_bh(&sta->lock);
	mpl_dbg("Mesh plink: starting establishment with %pM\n",
		sta->sta.addr);

	return mesh_plink_frame_tx(sdata, PLINK_OPEN,
				   sta->sta.addr, llid, 0, 0);
}
Exemplo n.º 3
0
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_ON(!local->ops->ampdu_action))
        return -EINVAL;

    if ((tid >= STA_TID_NUM) ||
            !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) ||
            (local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW))
        return -EINVAL;

#ifdef CONFIG_MAC80211_HT_DEBUG
    printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
           pubsta->addr, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */

    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)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
        printk(KERN_DEBUG "BA sessions blocked. "
               "Denying BA session request\n");
#endif
        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) {
#ifdef CONFIG_MAC80211_HT_DEBUG
        printk(KERN_DEBUG "BA request denied - IBSS STA %pM"
               "does not advertise HT support\n", pubsta->addr);
#endif /* CONFIG_MAC80211_HT_DEBUG */
        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)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
        printk(KERN_DEBUG "BA request denied - "
               "waiting a grace period after %d failed requests "
               "on tid %u\n",
               sta->ampdu_mlme.addba_req_num[tid], tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
        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]) {
#ifdef CONFIG_MAC80211_HT_DEBUG
        printk(KERN_DEBUG "BA request denied - session is not "
               "idle on tid %u\n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
        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;

    /* response timer */
    tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
    tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
    init_timer(&tid_tx->addba_resp_timer);

    /* tx timer */
    tid_tx->session_timer.function = sta_tx_agg_session_timer_expired;
    tid_tx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
    init_timer_deferrable(&tid_tx->session_timer);

    /* 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;
}
void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
			 size_t len, struct ieee80211_rx_status *rx_status)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee802_11_elems elems;
	struct sta_info *sta;
	enum plink_event event;
	enum plink_frame_type ftype;
	size_t baselen;
	bool deactivated, matches_local = true;
	u8 ie_len;
	u8 *baseaddr;
	__le16 plid, llid, reason;
#ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
	static const char *mplstates[] = {
		[NL80211_PLINK_LISTEN] = "LISTEN",
		[NL80211_PLINK_OPN_SNT] = "OPN-SNT",
		[NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
		[NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
		[NL80211_PLINK_ESTAB] = "ESTAB",
		[NL80211_PLINK_HOLDING] = "HOLDING",
		[NL80211_PLINK_BLOCKED] = "BLOCKED"
	};
#endif

	/* need action_code, aux */
	if (len < IEEE80211_MIN_ACTION_SIZE + 3)
		return;

	if (is_multicast_ether_addr(mgmt->da)) {
		mpl_dbg("Mesh plink: ignore frame from multicast address");
		return;
	}

	baseaddr = mgmt->u.action.u.plink_action.variable;
	baselen = (u8 *) mgmt->u.action.u.plink_action.variable - (u8 *) mgmt;
	if (mgmt->u.action.u.plink_action.action_code == PLINK_CONFIRM) {
		baseaddr += 4;
		baselen += 4;
	}
	ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
	if (!elems.peer_link) {
		mpl_dbg("Mesh plink: missing necessary peer link ie\n");
		return;
	}
	if (elems.rsn_len &&
			sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
		mpl_dbg("Mesh plink: can't establish link with secure peer\n");
		return;
	}

	ftype = mgmt->u.action.u.plink_action.action_code;
	ie_len = elems.peer_link_len;
	if ((ftype == PLINK_OPEN && ie_len != 6) ||
	    (ftype == PLINK_CONFIRM && ie_len != 8) ||
	    (ftype == PLINK_CLOSE && ie_len != 8 && ie_len != 10)) {
		mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
		    ftype, ie_len);
		return;
	}

	if (ftype != PLINK_CLOSE && (!elems.mesh_id || !elems.mesh_config)) {
		mpl_dbg("Mesh plink: missing necessary ie\n");
		return;
	}
	/* Note the lines below are correct, the llid in the frame is the plid
	 * from the point of view of this host.
	 */
	memcpy(&plid, PLINK_GET_LLID(elems.peer_link), 2);
	if (ftype == PLINK_CONFIRM || (ftype == PLINK_CLOSE && ie_len == 10))
		memcpy(&llid, PLINK_GET_PLID(elems.peer_link), 2);

	rcu_read_lock();

	sta = sta_info_get(sdata, mgmt->sa);
	if (!sta && ftype != PLINK_OPEN) {
		mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
		rcu_read_unlock();
		return;
	}

	if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) {
		mpl_dbg("Mesh plink: Action frame from non-authed peer\n");
		rcu_read_unlock();
		return;
	}

	if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) {
		rcu_read_unlock();
		return;
	}

	/* Now we will figure out the appropriate event... */
	event = PLINK_UNDEFINED;
	if (ftype != PLINK_CLOSE && (!mesh_matches_local(&elems, sdata))) {
		matches_local = false;
		switch (ftype) {
		case PLINK_OPEN:
			event = OPN_RJCT;
			break;
		case PLINK_CONFIRM:
			event = CNF_RJCT;
			break;
		case PLINK_CLOSE:
			/* avoid warning */
			break;
		}
	}

	if (!sta && !matches_local) {
		rcu_read_unlock();
		reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
		llid = 0;
		mesh_plink_frame_tx(sdata, PLINK_CLOSE, mgmt->sa, llid,
				    plid, reason);
		return;
	} else if (!sta) {
		/* ftype == PLINK_OPEN */
		u32 rates;

		rcu_read_unlock();

		if (!mesh_plink_free_count(sdata)) {
			mpl_dbg("Mesh plink error: no more free plinks\n");
			return;
		}

		rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
		sta = mesh_plink_alloc(sdata, mgmt->sa, rates);
		if (!sta) {
			mpl_dbg("Mesh plink error: plink table full\n");
			return;
		}
		if (sta_info_insert_rcu(sta)) {
			rcu_read_unlock();
			return;
		}
		event = OPN_ACPT;
		spin_lock_bh(&sta->lock);
	} else if (matches_local) {
		spin_lock_bh(&sta->lock);
		switch (ftype) {
		case PLINK_OPEN:
			if (!mesh_plink_free_count(sdata) ||
			    (sta->plid && sta->plid != plid))
				event = OPN_IGNR;
			else
				event = OPN_ACPT;
			break;
		case PLINK_CONFIRM:
			if (!mesh_plink_free_count(sdata) ||
			    (sta->llid != llid || sta->plid != plid))
				event = CNF_IGNR;
			else
				event = CNF_ACPT;
			break;
		case PLINK_CLOSE:
			if (sta->plink_state == NL80211_PLINK_ESTAB)
				/* Do not check for llid or plid. This does not
				 * follow the standard but since multiple plinks
				 * per sta are not supported, it is necessary in
				 * order to avoid a livelock when MP A sees an
				 * establish peer link to MP B but MP B does not
				 * see it. This can be caused by a timeout in
				 * B's peer link establishment or B beign
				 * restarted.
				 */
				event = CLS_ACPT;
			else if (sta->plid != plid)
				event = CLS_IGNR;
			else if (ie_len == 7 && sta->llid != llid)
				event = CLS_IGNR;
			else
				event = CLS_ACPT;
			break;
		default:
			mpl_dbg("Mesh plink: unknown frame subtype\n");
			spin_unlock_bh(&sta->lock);
			rcu_read_unlock();
			return;
		}
	} else {
		spin_lock_bh(&sta->lock);
	}

	mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
		mgmt->sa, mplstates[sta->plink_state],
		le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
		event);
	reason = 0;
	switch (sta->plink_state) {
		/* spin_unlock as soon as state is updated at each case */
	case NL80211_PLINK_LISTEN:
		switch (event) {
		case CLS_ACPT:
			mesh_plink_fsm_restart(sta);
			spin_unlock_bh(&sta->lock);
			break;
		case OPN_ACPT:
			sta->plink_state = NL80211_PLINK_OPN_RCVD;
			sta->plid = plid;
			get_random_bytes(&llid, 2);
			sta->llid = llid;
			mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_OPEN, sta->sta.addr, llid,
					    0, 0);
			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr,
					    llid, plid, 0);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_OPN_SNT:
		switch (event) {
		case OPN_RJCT:
		case CNF_RJCT:
			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
		case CLS_ACPT:
			if (!reason)
				reason = cpu_to_le16(MESH_CLOSE_RCVD);
			sta->reason = reason;
			sta->plink_state = NL80211_PLINK_HOLDING;
			if (!mod_plink_timer(sta,
					     dot11MeshHoldingTimeout(sdata)))
				sta->ignore_plink_timer = true;

			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
					    plid, reason);
			break;
		case OPN_ACPT:
			/* retry timer is left untouched */
			sta->plink_state = NL80211_PLINK_OPN_RCVD;
			sta->plid = plid;
			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
					    plid, 0);
			break;
		case CNF_ACPT:
			sta->plink_state = NL80211_PLINK_CNF_RCVD;
			if (!mod_plink_timer(sta,
					     dot11MeshConfirmTimeout(sdata)))
				sta->ignore_plink_timer = true;

			spin_unlock_bh(&sta->lock);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_OPN_RCVD:
		switch (event) {
		case OPN_RJCT:
		case CNF_RJCT:
			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
		case CLS_ACPT:
			if (!reason)
				reason = cpu_to_le16(MESH_CLOSE_RCVD);
			sta->reason = reason;
			sta->plink_state = NL80211_PLINK_HOLDING;
			if (!mod_plink_timer(sta,
					     dot11MeshHoldingTimeout(sdata)))
				sta->ignore_plink_timer = true;

			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
					    plid, reason);
			break;
		case OPN_ACPT:
			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
					    plid, 0);
			break;
		case CNF_ACPT:
			del_timer(&sta->plink_timer);
			sta->plink_state = NL80211_PLINK_ESTAB;
			spin_unlock_bh(&sta->lock);
			mesh_plink_inc_estab_count(sdata);
			ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
				sta->sta.addr);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_CNF_RCVD:
		switch (event) {
		case OPN_RJCT:
		case CNF_RJCT:
			reason = cpu_to_le16(MESH_CAPABILITY_POLICY_VIOLATION);
		case CLS_ACPT:
			if (!reason)
				reason = cpu_to_le16(MESH_CLOSE_RCVD);
			sta->reason = reason;
			sta->plink_state = NL80211_PLINK_HOLDING;
			if (!mod_plink_timer(sta,
					     dot11MeshHoldingTimeout(sdata)))
				sta->ignore_plink_timer = true;

			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
					    plid, reason);
			break;
		case OPN_ACPT:
			del_timer(&sta->plink_timer);
			sta->plink_state = NL80211_PLINK_ESTAB;
			spin_unlock_bh(&sta->lock);
			mesh_plink_inc_estab_count(sdata);
			ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
				sta->sta.addr);
			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
					    plid, 0);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_ESTAB:
		switch (event) {
		case CLS_ACPT:
			reason = cpu_to_le16(MESH_CLOSE_RCVD);
			sta->reason = reason;
			deactivated = __mesh_plink_deactivate(sta);
			sta->plink_state = NL80211_PLINK_HOLDING;
			llid = sta->llid;
			mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
			spin_unlock_bh(&sta->lock);
			if (deactivated)
				ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr, llid,
					    plid, reason);
			break;
		case OPN_ACPT:
			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_CONFIRM, sta->sta.addr, llid,
					    plid, 0);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;
	case NL80211_PLINK_HOLDING:
		switch (event) {
		case CLS_ACPT:
			if (del_timer(&sta->plink_timer))
				sta->ignore_plink_timer = 1;
			mesh_plink_fsm_restart(sta);
			spin_unlock_bh(&sta->lock);
			break;
		case OPN_ACPT:
		case CNF_ACPT:
		case OPN_RJCT:
		case CNF_RJCT:
			llid = sta->llid;
			reason = sta->reason;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, PLINK_CLOSE, sta->sta.addr,
					    llid, plid, reason);
			break;
		default:
			spin_unlock_bh(&sta->lock);
		}
		break;
	default:
		/* should not get here, PLINK_BLOCKED is dealt with at the
		 * beginning of the function
		 */
		spin_unlock_bh(&sta->lock);
		break;
	}

	rcu_read_unlock();
}
Exemplo n.º 5
0
void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt,
			 size_t len, struct ieee80211_rx_status *rx_status)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee802_11_elems elems;
	struct sta_info *sta;
	enum plink_event event;
	enum ieee80211_self_protected_actioncode ftype;
	size_t baselen;
	bool deactivated, matches_local = true;
	u8 ie_len;
	u8 *baseaddr;
	__le16 plid, llid, reason;
#ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG
	static const char *mplstates[] = {
		[NL80211_PLINK_LISTEN] = "LISTEN",
		[NL80211_PLINK_OPN_SNT] = "OPN-SNT",
		[NL80211_PLINK_OPN_RCVD] = "OPN-RCVD",
		[NL80211_PLINK_CNF_RCVD] = "CNF_RCVD",
		[NL80211_PLINK_ESTAB] = "ESTAB",
		[NL80211_PLINK_HOLDING] = "HOLDING",
		[NL80211_PLINK_BLOCKED] = "BLOCKED"
	};
#endif

	/*                       */
	if (len < IEEE80211_MIN_ACTION_SIZE + 3)
		return;

	if (is_multicast_ether_addr(mgmt->da)) {
		mpl_dbg("Mesh plink: ignore frame from multicast address");
		return;
	}

	baseaddr = mgmt->u.action.u.self_prot.variable;
	baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt;
	if (mgmt->u.action.u.self_prot.action_code ==
						WLAN_SP_MESH_PEERING_CONFIRM) {
		baseaddr += 4;
		baselen += 4;
	}
	ieee802_11_parse_elems(baseaddr, len - baselen, &elems);
	if (!elems.peering) {
		mpl_dbg("Mesh plink: missing necessary peer link ie\n");
		return;
	}
	if (elems.rsn_len &&
			sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) {
		mpl_dbg("Mesh plink: can't establish link with secure peer\n");
		return;
	}

	ftype = mgmt->u.action.u.self_prot.action_code;
	ie_len = elems.peering_len;
	if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) ||
	    (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) ||
	    (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6
							&& ie_len != 8)) {
		mpl_dbg("Mesh plink: incorrect plink ie length %d %d\n",
		    ftype, ie_len);
		return;
	}

	if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
				(!elems.mesh_id || !elems.mesh_config)) {
		mpl_dbg("Mesh plink: missing necessary ie\n");
		return;
	}
	/*                                                                    
                                        
  */
	memcpy(&plid, PLINK_GET_LLID(elems.peering), 2);
	if (ftype == WLAN_SP_MESH_PEERING_CONFIRM ||
	    (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8))
		memcpy(&llid, PLINK_GET_PLID(elems.peering), 2);

	rcu_read_lock();

	sta = sta_info_get(sdata, mgmt->sa);
	if (!sta && ftype != WLAN_SP_MESH_PEERING_OPEN) {
		mpl_dbg("Mesh plink: cls or cnf from unknown peer\n");
		rcu_read_unlock();
		return;
	}

	if (ftype == WLAN_SP_MESH_PEERING_OPEN &&
	    !rssi_threshold_check(sta, sdata)) {
		mpl_dbg("Mesh plink: %pM does not meet rssi threshold\n",
			mgmt->sa);
		rcu_read_unlock();
		return;
	}

	if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) {
		mpl_dbg("Mesh plink: Action frame from non-authed peer\n");
		rcu_read_unlock();
		return;
	}

	if (sta && sta->plink_state == NL80211_PLINK_BLOCKED) {
		rcu_read_unlock();
		return;
	}

	/*                                                 */
	event = PLINK_UNDEFINED;
	if (ftype != WLAN_SP_MESH_PEERING_CLOSE &&
	    (!mesh_matches_local(&elems, sdata))) {
		matches_local = false;
		switch (ftype) {
		case WLAN_SP_MESH_PEERING_OPEN:
			event = OPN_RJCT;
			break;
		case WLAN_SP_MESH_PEERING_CONFIRM:
			event = CNF_RJCT;
			break;
		default:
			break;
		}
	}

	if (!sta && !matches_local) {
		rcu_read_unlock();
		reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG);
		llid = 0;
		mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE,
				    mgmt->sa, llid, plid, reason);
		return;
	} else if (!sta) {
		/*                                    */
		u32 rates;

		rcu_read_unlock();

		if (!mesh_plink_free_count(sdata)) {
			mpl_dbg("Mesh plink error: no more free plinks\n");
			return;
		}

		rates = ieee80211_sta_get_rates(local, &elems, rx_status->band);
		sta = mesh_plink_alloc(sdata, mgmt->sa, rates, &elems);
		if (!sta) {
			mpl_dbg("Mesh plink error: plink table full\n");
			return;
		}
		if (sta_info_insert_rcu(sta)) {
			rcu_read_unlock();
			return;
		}
		event = OPN_ACPT;
		spin_lock_bh(&sta->lock);
	} else if (matches_local) {
		spin_lock_bh(&sta->lock);
		switch (ftype) {
		case WLAN_SP_MESH_PEERING_OPEN:
			if (!mesh_plink_free_count(sdata) ||
			    (sta->plid && sta->plid != plid))
				event = OPN_IGNR;
			else
				event = OPN_ACPT;
			break;
		case WLAN_SP_MESH_PEERING_CONFIRM:
			if (!mesh_plink_free_count(sdata) ||
			    (sta->llid != llid || sta->plid != plid))
				event = CNF_IGNR;
			else
				event = CNF_ACPT;
			break;
		case WLAN_SP_MESH_PEERING_CLOSE:
			if (sta->plink_state == NL80211_PLINK_ESTAB)
				/*                                             
                                                    
                                                    
                                                  
                                                    
                                                 
                                             
                 
     */
				event = CLS_ACPT;
			else if (sta->plid != plid)
				event = CLS_IGNR;
			else if (ie_len == 7 && sta->llid != llid)
				event = CLS_IGNR;
			else
				event = CLS_ACPT;
			break;
		default:
			mpl_dbg("Mesh plink: unknown frame subtype\n");
			spin_unlock_bh(&sta->lock);
			rcu_read_unlock();
			return;
		}
	} else {
		spin_lock_bh(&sta->lock);
	}

	mpl_dbg("Mesh plink (peer, state, llid, plid, event): %pM %s %d %d %d\n",
		mgmt->sa, mplstates[sta->plink_state],
		le16_to_cpu(sta->llid), le16_to_cpu(sta->plid),
		event);
	reason = 0;
	switch (sta->plink_state) {
		/*                                                      */
	case NL80211_PLINK_LISTEN:
		switch (event) {
		case CLS_ACPT:
			mesh_plink_fsm_restart(sta);
			spin_unlock_bh(&sta->lock);
			break;
		case OPN_ACPT:
			sta->plink_state = NL80211_PLINK_OPN_RCVD;
			sta->plid = plid;
			get_random_bytes(&llid, 2);
			sta->llid = llid;
			mesh_plink_timer_set(sta, dot11MeshRetryTimeout(sdata));
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_OPEN,
					    sta->sta.addr, llid, 0, 0);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_CONFIRM,
					    sta->sta.addr, llid, plid, 0);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_OPN_SNT:
		switch (event) {
		case OPN_RJCT:
		case CNF_RJCT:
			reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG);
		case CLS_ACPT:
			if (!reason)
				reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE);
			sta->reason = reason;
			sta->plink_state = NL80211_PLINK_HOLDING;
			if (!mod_plink_timer(sta,
					     dot11MeshHoldingTimeout(sdata)))
				sta->ignore_plink_timer = true;

			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_CLOSE,
					    sta->sta.addr, llid, plid, reason);
			break;
		case OPN_ACPT:
			/*                               */
			sta->plink_state = NL80211_PLINK_OPN_RCVD;
			sta->plid = plid;
			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_CONFIRM,
					    sta->sta.addr, llid, plid, 0);
			break;
		case CNF_ACPT:
			sta->plink_state = NL80211_PLINK_CNF_RCVD;
			if (!mod_plink_timer(sta,
					     dot11MeshConfirmTimeout(sdata)))
				sta->ignore_plink_timer = true;

			spin_unlock_bh(&sta->lock);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_OPN_RCVD:
		switch (event) {
		case OPN_RJCT:
		case CNF_RJCT:
			reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG);
		case CLS_ACPT:
			if (!reason)
				reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE);
			sta->reason = reason;
			sta->plink_state = NL80211_PLINK_HOLDING;
			if (!mod_plink_timer(sta,
					     dot11MeshHoldingTimeout(sdata)))
				sta->ignore_plink_timer = true;

			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE,
					    sta->sta.addr, llid, plid, reason);
			break;
		case OPN_ACPT:
			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_CONFIRM,
					    sta->sta.addr, llid, plid, 0);
			break;
		case CNF_ACPT:
			del_timer(&sta->plink_timer);
			sta->plink_state = NL80211_PLINK_ESTAB;
			spin_unlock_bh(&sta->lock);
			mesh_plink_inc_estab_count(sdata);
			ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
				sta->sta.addr);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_CNF_RCVD:
		switch (event) {
		case OPN_RJCT:
		case CNF_RJCT:
			reason = cpu_to_le16(WLAN_REASON_MESH_CONFIG);
		case CLS_ACPT:
			if (!reason)
				reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE);
			sta->reason = reason;
			sta->plink_state = NL80211_PLINK_HOLDING;
			if (!mod_plink_timer(sta,
					     dot11MeshHoldingTimeout(sdata)))
				sta->ignore_plink_timer = true;

			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_CLOSE,
					    sta->sta.addr, llid, plid, reason);
			break;
		case OPN_ACPT:
			del_timer(&sta->plink_timer);
			sta->plink_state = NL80211_PLINK_ESTAB;
			spin_unlock_bh(&sta->lock);
			mesh_plink_inc_estab_count(sdata);
			ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
			mpl_dbg("Mesh plink with %pM ESTABLISHED\n",
				sta->sta.addr);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_CONFIRM,
					    sta->sta.addr, llid, plid, 0);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;

	case NL80211_PLINK_ESTAB:
		switch (event) {
		case CLS_ACPT:
			reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE);
			sta->reason = reason;
			deactivated = __mesh_plink_deactivate(sta);
			sta->plink_state = NL80211_PLINK_HOLDING;
			llid = sta->llid;
			mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata));
			spin_unlock_bh(&sta->lock);
			if (deactivated)
				ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON);
			mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE,
					    sta->sta.addr, llid, plid, reason);
			break;
		case OPN_ACPT:
			llid = sta->llid;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata,
					    WLAN_SP_MESH_PEERING_CONFIRM,
					    sta->sta.addr, llid, plid, 0);
			break;
		default:
			spin_unlock_bh(&sta->lock);
			break;
		}
		break;
	case NL80211_PLINK_HOLDING:
		switch (event) {
		case CLS_ACPT:
			if (del_timer(&sta->plink_timer))
				sta->ignore_plink_timer = 1;
			mesh_plink_fsm_restart(sta);
			spin_unlock_bh(&sta->lock);
			break;
		case OPN_ACPT:
		case CNF_ACPT:
		case OPN_RJCT:
		case CNF_RJCT:
			llid = sta->llid;
			reason = sta->reason;
			spin_unlock_bh(&sta->lock);
			mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE,
					    sta->sta.addr, llid, plid, reason);
			break;
		default:
			spin_unlock_bh(&sta->lock);
		}
		break;
	default:
		/*                                                        
                              
   */
		spin_unlock_bh(&sta->lock);
		break;
	}

	rcu_read_unlock();
}
Exemplo n.º 6
0
static void mesh_sync_offset_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
				   u16 stype,
				   struct ieee80211_mgmt *mgmt,
				   struct ieee802_11_elems *elems,
				   struct ieee80211_rx_status *rx_status)
{
	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
	struct ieee80211_local *local = sdata->local;
	struct sta_info *sta;
	u64 t_t, t_r;

	WARN_ON(ifmsh->mesh_sp_id != IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET);

	/* standard mentions only beacons */
	if (stype != IEEE80211_STYPE_BEACON)
		return;

	/*
	 * Get time when timestamp field was received.  If we don't
	 * have rx timestamps, then use current tsf as an approximation.
	 * drv_get_tsf() must be called before entering the rcu-read
	 * section.
	 */
	if (ieee80211_have_rx_timestamp(rx_status))
		t_r = ieee80211_calculate_rx_timestamp(local, rx_status,
						       24 + 12 +
						       elems->total_len +
						       FCS_LEN,
						       24);
	else
		t_r = drv_get_tsf(local, sdata);

	rcu_read_lock();
	sta = sta_info_get(sdata, mgmt->sa);
	if (!sta)
		goto no_sync;

	/* check offset sync conditions (13.13.2.2.1)
	 *
	 * TODO also sync to
	 * dot11MeshNbrOffsetMaxNeighbor non-peer non-MBSS neighbors
	 */

	if (elems->mesh_config && mesh_peer_tbtt_adjusting(elems)) {
		msync_dbg(sdata, "STA %pM : is adjusting TBTT\n",
			  sta->sta.addr);
		goto no_sync;
	}

	/* Timing offset calculation (see 13.13.2.2.2) */
	t_t = le64_to_cpu(mgmt->u.beacon.timestamp);
	sta->mesh->t_offset = t_t - t_r;

	if (test_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN)) {
		s64 t_clockdrift = sta->mesh->t_offset_setpoint - sta->mesh->t_offset;
		msync_dbg(sdata,
			  "STA %pM : t_offset=%lld, t_offset_setpoint=%lld, t_clockdrift=%lld\n",
			  sta->sta.addr, (long long) sta->mesh->t_offset,
			  (long long) sta->mesh->t_offset_setpoint,
			  (long long) t_clockdrift);

		if (t_clockdrift > TOFFSET_MAXIMUM_ADJUSTMENT ||
		    t_clockdrift < -TOFFSET_MAXIMUM_ADJUSTMENT) {
			msync_dbg(sdata,
				  "STA %pM : t_clockdrift=%lld too large, setpoint reset\n",
				  sta->sta.addr,
				  (long long) t_clockdrift);
			clear_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN);
			goto no_sync;
		}

		spin_lock_bh(&ifmsh->sync_offset_lock);
		if (t_clockdrift > ifmsh->sync_offset_clockdrift_max)
			ifmsh->sync_offset_clockdrift_max = t_clockdrift;
		spin_unlock_bh(&ifmsh->sync_offset_lock);
	} else {
		sta->mesh->t_offset_setpoint = sta->mesh->t_offset - TOFFSET_SET_MARGIN;
		set_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN);
		msync_dbg(sdata,
			  "STA %pM : offset was invalid, t_offset=%lld\n",
			  sta->sta.addr,
			  (long long) sta->mesh->t_offset);
	}

no_sync:
	rcu_read_unlock();
}
Exemplo n.º 7
0
Arquivo: wme.c Projeto: 7799/linux
/* Indicate which queue to use. */
u16 ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
			   struct sk_buff *skb)
{
	struct ieee80211_local *local = sdata->local;
	struct sta_info *sta = NULL;
	const u8 *ra = NULL;
	bool qos = false;
	struct mac80211_qos_map *qos_map;

	if (local->hw.queues < IEEE80211_NUM_ACS || skb->len < 6) {
		skb->priority = 0; /* required for correct WPA/11i MIC */
		return 0;
	}

	rcu_read_lock();
	switch (sdata->vif.type) {
	case NL80211_IFTYPE_AP_VLAN:
		sta = rcu_dereference(sdata->u.vlan.sta);
		if (sta) {
			qos = test_sta_flag(sta, WLAN_STA_WME);
			break;
		}
	case NL80211_IFTYPE_AP:
		ra = skb->data;
		break;
	case NL80211_IFTYPE_WDS:
		ra = sdata->u.wds.remote_addr;
		break;
#ifdef CONFIG_MAC80211_MESH
	case NL80211_IFTYPE_MESH_POINT:
		qos = true;
		break;
#endif
	case NL80211_IFTYPE_STATION:
		ra = sdata->u.mgd.bssid;
		break;
	case NL80211_IFTYPE_ADHOC:
		ra = skb->data;
		break;
	default:
		break;
	}

	if (!sta && ra && !is_multicast_ether_addr(ra)) {
		sta = sta_info_get(sdata, ra);
		if (sta)
			qos = test_sta_flag(sta, WLAN_STA_WME);
	}
	rcu_read_unlock();

	if (!qos) {
		skb->priority = 0; /* required for correct WPA/11i MIC */
		return IEEE80211_AC_BE;
	}

	if (skb->protocol == sdata->control_port_protocol) {
		skb->priority = 7;
		return ieee80211_downgrade_queue(sdata, skb);
	}

	/* use the data classifier to determine what 802.1d tag the
	 * data frame has */
	rcu_read_lock();
	qos_map = rcu_dereference(sdata->qos_map);
	skb->priority = cfg80211_classify8021d(skb, qos_map ?
					       &qos_map->qos_map : NULL);
	rcu_read_unlock();

	return ieee80211_downgrade_queue(sdata, skb);
}
Exemplo n.º 8
0
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_ON(!local->ops->ampdu_action))
		return -EINVAL;

	if ((tid >= STA_TID_NUM) ||
	    !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) ||
	    (local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW))
		return -EINVAL;

#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
	       pubsta->addr, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	/*
	 * The aggregation code is not prepared to handle
	 * anything but STA/AP due to the BSSID handling.
	 * IBSS could work in the code but isn't supported
	 * by drivers or the standard.
	 */
	if (sdata->vif.type != NL80211_IFTYPE_STATION &&
	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
	    sdata->vif.type != NL80211_IFTYPE_AP)
		return -EINVAL;

	if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "BA sessions blocked. "
		       "Denying BA session request\n");
#endif
		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;
	}

	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]) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "BA request denied - session is not "
				 "idle on tid %u\n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
		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;

	/* Tx timer */
	tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
	tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
	init_timer(&tid_tx->addba_resp_timer);

	/* 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;
}
Exemplo n.º 9
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, &params);
		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, &params);

	/* 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, &params);
	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, &params);

	/*
	 * 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);
}