/******************************************************************************
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2008 - 2014 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
 * USA
 *
 * The full GNU General Public License is included in this distribution
 * in the file called COPYING.
 *
 * Contact Information:
 *  Intel Linux Wireless <linuxwifi@intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 *****************************************************************************/

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/ieee80211.h>
#include "iwl-io.h"
#include "iwl-trans.h"
#include "iwl-agn-hw.h"
#include "dev.h"
#include "agn.h"

static const u8 tid_to_ac[] = {
        IEEE80211_AC_BE,
        IEEE80211_AC_BK,
        IEEE80211_AC_BK,
        IEEE80211_AC_BE,
        IEEE80211_AC_VI,
        IEEE80211_AC_VI,
        IEEE80211_AC_VO,
        IEEE80211_AC_VO,
};

static void iwlagn_tx_cmd_protection(struct iwl_priv *priv,
                                     struct ieee80211_tx_info *info,
                                     __le16 fc, __le32 *tx_flags)
{
        if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS ||
            info->control.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT ||
            info->flags & IEEE80211_TX_CTL_AMPDU)
                *tx_flags |= TX_CMD_FLG_PROT_REQUIRE_MSK;
}

/*
 * handle build REPLY_TX command notification.
 */
static void iwlagn_tx_cmd_build_basic(struct iwl_priv *priv,
                                      struct sk_buff *skb,
                                      struct iwl_tx_cmd *tx_cmd,
                                      struct ieee80211_tx_info *info,
                                      struct ieee80211_hdr *hdr, u8 sta_id)
{
        __le16 fc = hdr->frame_control;
        __le32 tx_flags = tx_cmd->tx_flags;

        tx_cmd->stop_time.life_time = TX_CMD_LIFE_TIME_INFINITE;

        if (!(info->flags & IEEE80211_TX_CTL_NO_ACK))
                tx_flags |= TX_CMD_FLG_ACK_MSK;
        else
                tx_flags &= ~TX_CMD_FLG_ACK_MSK;

        if (ieee80211_is_probe_resp(fc))
                tx_flags |= TX_CMD_FLG_TSF_MSK;
        else if (ieee80211_is_back_req(fc))
                tx_flags |= TX_CMD_FLG_ACK_MSK | TX_CMD_FLG_IMM_BA_RSP_MASK;
        else if (info->band == NL80211_BAND_2GHZ &&
                 priv->lib->bt_params &&
                 priv->lib->bt_params->advanced_bt_coexist &&
                 (ieee80211_is_auth(fc) || ieee80211_is_assoc_req(fc) ||
                 ieee80211_is_reassoc_req(fc) ||
                 info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO))
                tx_flags |= TX_CMD_FLG_IGNORE_BT;


        tx_cmd->sta_id = sta_id;
        if (ieee80211_has_morefrags(fc))
                tx_flags |= TX_CMD_FLG_MORE_FRAG_MSK;

        if (ieee80211_is_data_qos(fc)) {
                u8 *qc = ieee80211_get_qos_ctl(hdr);
                tx_cmd->tid_tspec = qc[0] & 0xf;
                tx_flags &= ~TX_CMD_FLG_SEQ_CTL_MSK;
        } else {
                tx_cmd->tid_tspec = IWL_TID_NON_QOS;
                if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ)
                        tx_flags |= TX_CMD_FLG_SEQ_CTL_MSK;
                else
                        tx_flags &= ~TX_CMD_FLG_SEQ_CTL_MSK;
        }

        iwlagn_tx_cmd_protection(priv, info, fc, &tx_flags);

        tx_flags &= ~(TX_CMD_FLG_ANT_SEL_MSK);
        if (ieee80211_is_mgmt(fc)) {
                if (ieee80211_is_assoc_req(fc) || ieee80211_is_reassoc_req(fc))
                        tx_cmd->timeout.pm_frame_timeout = cpu_to_le16(3);
                else
                        tx_cmd->timeout.pm_frame_timeout = cpu_to_le16(2);
        } else {
                tx_cmd->timeout.pm_frame_timeout = 0;
        }

        tx_cmd->driver_txop = 0;
        tx_cmd->tx_flags = tx_flags;
        tx_cmd->next_frame_len = 0;
}

static void iwlagn_tx_cmd_build_rate(struct iwl_priv *priv,
                                     struct iwl_tx_cmd *tx_cmd,
                                     struct ieee80211_tx_info *info,
                                     struct ieee80211_sta *sta,
                                     __le16 fc)
{
        u32 rate_flags;
        int rate_idx;
        u8 rts_retry_limit;
        u8 data_retry_limit;
        u8 rate_plcp;

        if (priv->wowlan) {
                rts_retry_limit = IWLAGN_LOW_RETRY_LIMIT;
                data_retry_limit = IWLAGN_LOW_RETRY_LIMIT;
        } else {
                /* Set retry limit on RTS packets */
                rts_retry_limit = IWLAGN_RTS_DFAULT_RETRY_LIMIT;

                /* Set retry limit on DATA packets and Probe Responses*/
                if (ieee80211_is_probe_resp(fc)) {
                        data_retry_limit = IWLAGN_MGMT_DFAULT_RETRY_LIMIT;
                        rts_retry_limit =
                                min(data_retry_limit, rts_retry_limit);
                } else if (ieee80211_is_back_req(fc))
                        data_retry_limit = IWLAGN_BAR_DFAULT_RETRY_LIMIT;
                else
                        data_retry_limit = IWLAGN_DEFAULT_TX_RETRY;
        }

        tx_cmd->data_retry_limit = data_retry_limit;
        tx_cmd->rts_retry_limit = rts_retry_limit;

        /* DATA packets will use the uCode station table for rate/antenna
         * selection */
        if (ieee80211_is_data(fc)) {
                tx_cmd->initial_rate_index = 0;
                tx_cmd->tx_flags |= TX_CMD_FLG_STA_RATE_MSK;
                return;
        } else if (ieee80211_is_back_req(fc))
                tx_cmd->tx_flags |= TX_CMD_FLG_STA_RATE_MSK;

        /**
         * If the current TX rate stored in mac80211 has the MCS bit set, it's
         * not really a TX rate.  Thus, we use the lowest supported rate for
         * this band.  Also use the lowest supported rate if the stored rate
         * index is invalid.
         */
        rate_idx = info->control.rates[0].idx;
        if (info->control.rates[0].flags & IEEE80211_TX_RC_MCS ||
                        (rate_idx < 0) || (rate_idx > IWL_RATE_COUNT_LEGACY))
                rate_idx = rate_lowest_index(
                                &priv->nvm_data->bands[info->band], sta);
        /* For 5 GHZ band, remap mac80211 rate indices into driver indices */
        if (info->band == NL80211_BAND_5GHZ)
                rate_idx += IWL_FIRST_OFDM_RATE;
        /* Get PLCP rate for tx_cmd->rate_n_flags */
        rate_plcp = iwl_rates[rate_idx].plcp;
        /* Zero out flags for this packet */
        rate_flags = 0;

        /* Set CCK flag as needed */
        if ((rate_idx >= IWL_FIRST_CCK_RATE) && (rate_idx <= IWL_LAST_CCK_RATE))
                rate_flags |= RATE_MCS_CCK_MSK;

        /* Set up antennas */
        if (priv->lib->bt_params &&
            priv->lib->bt_params->advanced_bt_coexist &&
            priv->bt_full_concurrent) {
                /* operated as 1x1 in full concurrency mode */
                priv->mgmt_tx_ant = iwl_toggle_tx_ant(priv, priv->mgmt_tx_ant,
                                first_antenna(priv->nvm_data->valid_tx_ant));
        } else
                priv->mgmt_tx_ant = iwl_toggle_tx_ant(
                                        priv, priv->mgmt_tx_ant,
                                        priv->nvm_data->valid_tx_ant);
        rate_flags |= iwl_ant_idx_to_flags(priv->mgmt_tx_ant);

        /* Set the rate in the TX cmd */
        tx_cmd->rate_n_flags = iwl_hw_set_rate_n_flags(rate_plcp, rate_flags);
}

static void iwlagn_tx_cmd_build_hwcrypto(struct iwl_priv *priv,
                                         struct ieee80211_tx_info *info,
                                         struct iwl_tx_cmd *tx_cmd,
                                         struct sk_buff *skb_frag)
{
        struct ieee80211_key_conf *keyconf = info->control.hw_key;

        switch (keyconf->cipher) {
        case WLAN_CIPHER_SUITE_CCMP:
                tx_cmd->sec_ctl = TX_CMD_SEC_CCM;
                memcpy(tx_cmd->key, keyconf->key, keyconf->keylen);
                if (info->flags & IEEE80211_TX_CTL_AMPDU)
                        tx_cmd->tx_flags |= TX_CMD_FLG_AGG_CCMP_MSK;
                break;

        case WLAN_CIPHER_SUITE_TKIP:
                tx_cmd->sec_ctl = TX_CMD_SEC_TKIP;
                ieee80211_get_tkip_p2k(keyconf, skb_frag, tx_cmd->key);
                break;

        case WLAN_CIPHER_SUITE_WEP104:
                tx_cmd->sec_ctl |= TX_CMD_SEC_KEY128;
                /* fall through */
        case WLAN_CIPHER_SUITE_WEP40:
                tx_cmd->sec_ctl |= (TX_CMD_SEC_WEP |
                        (keyconf->keyidx & TX_CMD_SEC_MSK) << TX_CMD_SEC_SHIFT);

                memcpy(&tx_cmd->key[3], keyconf->key, keyconf->keylen);

                IWL_DEBUG_TX(priv, "Configuring packet for WEP encryption "
                             "with key %d\n", keyconf->keyidx);
                break;

        default:
                IWL_ERR(priv, "Unknown encode cipher %x\n", keyconf->cipher);
                break;
        }
}

/**
 * iwl_sta_id_or_broadcast - return sta_id or broadcast sta
 * @context: the current context
 * @sta: mac80211 station
 *
 * In certain circumstances mac80211 passes a station pointer
 * that may be %NULL, for example during TX or key setup. In
 * that case, we need to use the broadcast station, so this
 * inline wraps that pattern.
 */
static int iwl_sta_id_or_broadcast(struct iwl_rxon_context *context,
                                   struct ieee80211_sta *sta)
{
        int sta_id;

        if (!sta)
                return context->bcast_sta_id;

        sta_id = iwl_sta_id(sta);

        /*
         * mac80211 should not be passing a partially
         * initialised station!
         */
        WARN_ON(sta_id == IWL_INVALID_STATION);

        return sta_id;
}

/*
 * start REPLY_TX command process
 */
int iwlagn_tx_skb(struct iwl_priv *priv,
                  struct ieee80211_sta *sta,
                  struct sk_buff *skb)
{
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        struct iwl_station_priv *sta_priv = NULL;
        struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
        struct iwl_device_cmd *dev_cmd;
        struct iwl_tx_cmd *tx_cmd;
        __le16 fc;
        u8 hdr_len;
        u16 len, seq_number = 0;
        u8 sta_id, tid = IWL_MAX_TID_COUNT;
        bool is_agg = false, is_data_qos = false;
        int txq_id;

        if (info->control.vif)
                ctx = iwl_rxon_ctx_from_vif(info->control.vif);

        if (iwl_is_rfkill(priv)) {
                IWL_DEBUG_DROP(priv, "Dropping - RF KILL\n");
                goto drop_unlock_priv;
        }

        fc = hdr->frame_control;

#ifdef CONFIG_IWLWIFI_DEBUG
        if (ieee80211_is_auth(fc))
                IWL_DEBUG_TX(priv, "Sending AUTH frame\n");
        else if (ieee80211_is_assoc_req(fc))
                IWL_DEBUG_TX(priv, "Sending ASSOC frame\n");
        else if (ieee80211_is_reassoc_req(fc))
                IWL_DEBUG_TX(priv, "Sending REASSOC frame\n");
#endif

        if (unlikely(ieee80211_is_probe_resp(fc))) {
                struct iwl_wipan_noa_data *noa_data =
                        rcu_dereference(priv->noa_data);

                if (noa_data &&
                    pskb_expand_head(skb, 0, noa_data->length,
                                     GFP_ATOMIC) == 0) {
                        skb_put_data(skb, noa_data->data, noa_data->length);
                        hdr = (struct ieee80211_hdr *)skb->data;
                }
        }

        hdr_len = ieee80211_hdrlen(fc);

        /* For management frames use broadcast id to do not break aggregation */
        if (!ieee80211_is_data(fc))
                sta_id = ctx->bcast_sta_id;
        else {
                /* Find index into station table for destination station */
                sta_id = iwl_sta_id_or_broadcast(ctx, sta);
                if (sta_id == IWL_INVALID_STATION) {
                        IWL_DEBUG_DROP(priv, "Dropping - INVALID STATION: %pM\n",
                                       hdr->addr1);
                        goto drop_unlock_priv;
                }
        }

        if (sta)
                sta_priv = (void *)sta->drv_priv;

        if (sta_priv && sta_priv->asleep &&
            (info->flags & IEEE80211_TX_CTL_NO_PS_BUFFER)) {
                /*
                 * This sends an asynchronous command to the device,
                 * but we can rely on it being processed before the
                 * next frame is processed -- and the next frame to
                 * this station is the one that will consume this
                 * counter.
                 * For now set the counter to just 1 since we do not
                 * support uAPSD yet.
                 *
                 * FIXME: If we get two non-bufferable frames one
                 * after the other, we might only send out one of
                 * them because this is racy.
                 */
                iwl_sta_modify_sleep_tx_count(priv, sta_id, 1);
        }

        dev_cmd = iwl_trans_alloc_tx_cmd(priv->trans);

        if (unlikely(!dev_cmd))
                goto drop_unlock_priv;

        memset(dev_cmd, 0, sizeof(*dev_cmd));
        dev_cmd->hdr.cmd = REPLY_TX;
        tx_cmd = (struct iwl_tx_cmd *) dev_cmd->payload;

        /* Total # bytes to be transmitted */
        len = (u16)skb->len;
        tx_cmd->len = cpu_to_le16(len);

        if (info->control.hw_key)
                iwlagn_tx_cmd_build_hwcrypto(priv, info, tx_cmd, skb);

        /* TODO need this for burst mode later on */
        iwlagn_tx_cmd_build_basic(priv, skb, tx_cmd, info, hdr, sta_id);

        iwlagn_tx_cmd_build_rate(priv, tx_cmd, info, sta, fc);

        memset(&info->status, 0, sizeof(info->status));
        memset(info->driver_data, 0, sizeof(info->driver_data));

        info->driver_data[0] = ctx;
        info->driver_data[1] = dev_cmd;
        /* From now on, we cannot access info->control */

        spin_lock(&priv->sta_lock);

        if (ieee80211_is_data_qos(fc) && !ieee80211_is_qos_nullfunc(fc)) {
                u8 *qc = NULL;
                struct iwl_tid_data *tid_data;
                qc = ieee80211_get_qos_ctl(hdr);
                tid = qc[0] & IEEE80211_QOS_CTL_TID_MASK;
                if (WARN_ON_ONCE(tid >= IWL_MAX_TID_COUNT))
                        goto drop_unlock_sta;
                tid_data = &priv->tid_data[sta_id][tid];

                /* aggregation is on for this <sta,tid> */
                if (info->flags & IEEE80211_TX_CTL_AMPDU &&
                    tid_data->agg.state != IWL_AGG_ON) {
                        IWL_ERR(priv,
                                "TX_CTL_AMPDU while not in AGG: Tx flags = 0x%08x, agg.state = %d\n",
                                info->flags, tid_data->agg.state);
                        IWL_ERR(priv, "sta_id = %d, tid = %d seq_num = %d\n",
                                sta_id, tid,
                                IEEE80211_SEQ_TO_SN(tid_data->seq_number));
                        goto drop_unlock_sta;
                }

                /* We can receive packets from the stack in IWL_AGG_{ON,OFF}
                 * only. Check this here.
                 */
                if (WARN_ONCE(tid_data->agg.state != IWL_AGG_ON &&
                              tid_data->agg.state != IWL_AGG_OFF,
                              "Tx while agg.state = %d\n", tid_data->agg.state))
                        goto drop_unlock_sta;

                seq_number = tid_data->seq_number;
                seq_number &= IEEE80211_SCTL_SEQ;
                hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
                hdr->seq_ctrl |= cpu_to_le16(seq_number);
                seq_number += 0x10;

                if (info->flags & IEEE80211_TX_CTL_AMPDU)
                        is_agg = true;
                is_data_qos = true;
        }

        /* Copy MAC header from skb into command buffer */
        memcpy(tx_cmd->hdr, hdr, hdr_len);

        txq_id = info->hw_queue;

        if (is_agg)
                txq_id = priv->tid_data[sta_id][tid].agg.txq_id;
        else if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
                /*
                 * The microcode will clear the more data
                 * bit in the last frame it transmits.
                 */
                hdr->frame_control |=
                        cpu_to_le16(IEEE80211_FCTL_MOREDATA);
        }

        WARN_ON_ONCE(is_agg &&
                     priv->queue_to_mac80211[txq_id] != info->hw_queue);

        IWL_DEBUG_TX(priv, "TX to [%d|%d] Q:%d - seq: 0x%x\n", sta_id, tid,
                     txq_id, seq_number);

        if (iwl_trans_tx(priv->trans, skb, dev_cmd, txq_id))
                goto drop_unlock_sta;

        if (is_data_qos && !ieee80211_has_morefrags(fc))
                priv->tid_data[sta_id][tid].seq_number = seq_number;

        spin_unlock(&priv->sta_lock);

        /*
         * Avoid atomic ops if it isn't an associated client.
         * Also, if this is a packet for aggregation, don't
         * increase the counter because the ucode will stop
         * aggregation queues when their respective station
         * goes to sleep.
         */
        if (sta_priv && sta_priv->client && !is_agg)
                atomic_inc(&sta_priv->pending_frames);

        return 0;

drop_unlock_sta:
        if (dev_cmd)
                iwl_trans_free_tx_cmd(priv->trans, dev_cmd);
        spin_unlock(&priv->sta_lock);
drop_unlock_priv:
        return -1;
}

static int iwlagn_alloc_agg_txq(struct iwl_priv *priv, int mq)
{
        int q;

        for (q = IWLAGN_FIRST_AMPDU_QUEUE;
             q < priv->cfg->base_params->num_of_queues; q++) {
                if (!test_and_set_bit(q, priv->agg_q_alloc)) {
                        priv->queue_to_mac80211[q] = mq;
                        return q;
                }
        }

        return -ENOSPC;
}

static void iwlagn_dealloc_agg_txq(struct iwl_priv *priv, int q)
{
        clear_bit(q, priv->agg_q_alloc);
        priv->queue_to_mac80211[q] = IWL_INVALID_MAC80211_QUEUE;
}

int iwlagn_tx_agg_stop(struct iwl_priv *priv, struct ieee80211_vif *vif,
                        struct ieee80211_sta *sta, u16 tid)
{
        struct iwl_tid_data *tid_data;
        int sta_id, txq_id;
        enum iwl_agg_state agg_state;

        sta_id = iwl_sta_id(sta);

        if (sta_id == IWL_INVALID_STATION) {
                IWL_ERR(priv, "Invalid station for AGG tid %d\n", tid);
                return -ENXIO;
        }

        spin_lock_bh(&priv->sta_lock);

        tid_data = &priv->tid_data[sta_id][tid];
        txq_id = tid_data->agg.txq_id;

        switch (tid_data->agg.state) {
        case IWL_EMPTYING_HW_QUEUE_ADDBA:
                /*
                * This can happen if the peer stops aggregation
                * again before we've had a chance to drain the
                * queue we selected previously, i.e. before the
                * session was really started completely.
                */
                IWL_DEBUG_HT(priv, "AGG stop before setup done\n");
                goto turn_off;
        case IWL_AGG_STARTING:
                /*
                 * This can happen when the session is stopped before
                 * we receive ADDBA response
                 */
                IWL_DEBUG_HT(priv, "AGG stop before AGG became operational\n");
                goto turn_off;
        case IWL_AGG_ON:
                break;
        default:
                IWL_WARN(priv,
                         "Stopping AGG while state not ON or starting for %d on %d (%d)\n",
                         sta_id, tid, tid_data->agg.state);
                spin_unlock_bh(&priv->sta_lock);
                return 0;
        }

        tid_data->agg.ssn = IEEE80211_SEQ_TO_SN(tid_data->seq_number);

        /* There are still packets for this RA / TID in the HW */
        if (!test_bit(txq_id, priv->agg_q_alloc)) {
                IWL_DEBUG_TX_QUEUES(priv,
                        "stopping AGG on STA/TID %d/%d but hwq %d not used\n",
                        sta_id, tid, txq_id);
        } else if (tid_data->agg.ssn != tid_data->next_reclaimed) {
                IWL_DEBUG_TX_QUEUES(priv,
                                    "Can't proceed: ssn %d, next_recl = %d\n",
                                    tid_data->agg.ssn,
                                    tid_data->next_reclaimed);
                tid_data->agg.state = IWL_EMPTYING_HW_QUEUE_DELBA;
                spin_unlock_bh(&priv->sta_lock);
                return 0;
        }

        IWL_DEBUG_TX_QUEUES(priv, "Can proceed: ssn = next_recl = %d\n",
                            tid_data->agg.ssn);
turn_off:
        agg_state = tid_data->agg.state;
        tid_data->agg.state = IWL_AGG_OFF;

        spin_unlock_bh(&priv->sta_lock);

        if (test_bit(txq_id, priv->agg_q_alloc)) {
                /*
                 * If the transport didn't know that we wanted to start
                 * agreggation, don't tell it that we want to stop them.
                 * This can happen when we don't get the addBA response on
                 * time, or we hadn't time to drain the AC queues.
                 */
                if (agg_state == IWL_AGG_ON)
                        iwl_trans_txq_disable(priv->trans, txq_id, true);
                else
                        IWL_DEBUG_TX_QUEUES(priv, "Don't disable tx agg: %d\n",
                                            agg_state);
                iwlagn_dealloc_agg_txq(priv, txq_id);
        }

        ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);

        return 0;
}

int iwlagn_tx_agg_start(struct iwl_priv *priv, struct ieee80211_vif *vif,
                        struct ieee80211_sta *sta, u16 tid, u16 *ssn)
{
        struct iwl_rxon_context *ctx = iwl_rxon_ctx_from_vif(vif);
        struct iwl_tid_data *tid_data;
        int sta_id, txq_id, ret;

        IWL_DEBUG_HT(priv, "TX AGG request on ra = %pM tid = %d\n",
                     sta->addr, tid);

        sta_id = iwl_sta_id(sta);
        if (sta_id == IWL_INVALID_STATION) {
                IWL_ERR(priv, "Start AGG on invalid station\n");
                return -ENXIO;
        }
        if (unlikely(tid >= IWL_MAX_TID_COUNT))
                return -EINVAL;

        if (priv->tid_data[sta_id][tid].agg.state != IWL_AGG_OFF) {
                IWL_ERR(priv, "Start AGG when state is not IWL_AGG_OFF !\n");
                return -ENXIO;
        }

        txq_id = iwlagn_alloc_agg_txq(priv, ctx->ac_to_queue[tid_to_ac[tid]]);
        if (txq_id < 0) {
                IWL_DEBUG_TX_QUEUES(priv,
                        "No free aggregation queue for %pM/%d\n",
                        sta->addr, tid);
                return txq_id;
        }

        ret = iwl_sta_tx_modify_enable_tid(priv, sta_id, tid);
        if (ret)
                return ret;

        spin_lock_bh(&priv->sta_lock);
        tid_data = &priv->tid_data[sta_id][tid];
        tid_data->agg.ssn = IEEE80211_SEQ_TO_SN(tid_data->seq_number);
        tid_data->agg.txq_id = txq_id;

        *ssn = tid_data->agg.ssn;

        if (*ssn == tid_data->next_reclaimed) {
                IWL_DEBUG_TX_QUEUES(priv, "Can proceed: ssn = next_recl = %d\n",
                                    tid_data->agg.ssn);
                tid_data->agg.state = IWL_AGG_STARTING;
                ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
        } else {
                IWL_DEBUG_TX_QUEUES(priv, "Can't proceed: ssn %d, "
                                    "next_reclaimed = %d\n",
                                    tid_data->agg.ssn,
                                    tid_data->next_reclaimed);
                tid_data->agg.state = IWL_EMPTYING_HW_QUEUE_ADDBA;
        }
        spin_unlock_bh(&priv->sta_lock);

        return ret;
}

int iwlagn_tx_agg_flush(struct iwl_priv *priv, struct ieee80211_vif *vif,
                        struct ieee80211_sta *sta, u16 tid)
{
        struct iwl_tid_data *tid_data;
        enum iwl_agg_state agg_state;
        int sta_id, txq_id;
        sta_id = iwl_sta_id(sta);

        /*
         * First set the agg state to OFF to avoid calling
         * ieee80211_stop_tx_ba_cb in iwlagn_check_ratid_empty.
         */
        spin_lock_bh(&priv->sta_lock);

        tid_data = &priv->tid_data[sta_id][tid];
        txq_id = tid_data->agg.txq_id;
        agg_state = tid_data->agg.state;
        IWL_DEBUG_TX_QUEUES(priv, "Flush AGG: sta %d tid %d q %d state %d\n",
                            sta_id, tid, txq_id, tid_data->agg.state);

        tid_data->agg.state = IWL_AGG_OFF;

        spin_unlock_bh(&priv->sta_lock);

        if (iwlagn_txfifo_flush(priv, BIT(txq_id)))
                IWL_ERR(priv, "Couldn't flush the AGG queue\n");

        if (test_bit(txq_id, priv->agg_q_alloc)) {
                /*
                 * If the transport didn't know that we wanted to start
                 * agreggation, don't tell it that we want to stop them.
                 * This can happen when we don't get the addBA response on
                 * time, or we hadn't time to drain the AC queues.
                 */
                if (agg_state == IWL_AGG_ON)
                        iwl_trans_txq_disable(priv->trans, txq_id, true);
                else
                        IWL_DEBUG_TX_QUEUES(priv, "Don't disable tx agg: %d\n",
                                            agg_state);
                iwlagn_dealloc_agg_txq(priv, txq_id);
        }

        return 0;
}

int iwlagn_tx_agg_oper(struct iwl_priv *priv, struct ieee80211_vif *vif,
                        struct ieee80211_sta *sta, u16 tid, u8 buf_size)
{
        struct iwl_station_priv *sta_priv = (void *) sta->drv_priv;
        struct iwl_rxon_context *ctx = iwl_rxon_ctx_from_vif(vif);
        int q, fifo;
        u16 ssn;

        buf_size = min_t(int, buf_size, LINK_QUAL_AGG_FRAME_LIMIT_DEF);

        spin_lock_bh(&priv->sta_lock);
        ssn = priv->tid_data[sta_priv->sta_id][tid].agg.ssn;
        q = priv->tid_data[sta_priv->sta_id][tid].agg.txq_id;
        priv->tid_data[sta_priv->sta_id][tid].agg.state = IWL_AGG_ON;
        spin_unlock_bh(&priv->sta_lock);

        fifo = ctx->ac_to_fifo[tid_to_ac[tid]];

        iwl_trans_txq_enable(priv->trans, q, fifo, sta_priv->sta_id, tid,
                             buf_size, ssn, 0);

        /*
         * If the limit is 0, then it wasn't initialised yet,
         * use the default. We can do that since we take the
         * minimum below, and we don't want to go above our
         * default due to hardware restrictions.
         */
        if (sta_priv->max_agg_bufsize == 0)
                sta_priv->max_agg_bufsize =
                        LINK_QUAL_AGG_FRAME_LIMIT_DEF;

        /*
         * Even though in theory the peer could have different
         * aggregation reorder buffer sizes for different sessions,
         * our ucode doesn't allow for that and has a global limit
         * for each station. Therefore, use the minimum of all the
         * aggregation sessions and our default value.
         */
        sta_priv->max_agg_bufsize =
                min(sta_priv->max_agg_bufsize, buf_size);

        if (priv->hw_params.use_rts_for_aggregation) {
                /*
                 * switch to RTS/CTS if it is the prefer protection
                 * method for HT traffic
                 */

                sta_priv->lq_sta.lq.general_params.flags |=
                        LINK_QUAL_FLAGS_SET_STA_TLC_RTS_MSK;
        }
        priv->agg_tids_count++;
        IWL_DEBUG_HT(priv, "priv->agg_tids_count = %u\n",
                     priv->agg_tids_count);

        sta_priv->lq_sta.lq.agg_params.agg_frame_cnt_limit =
                sta_priv->max_agg_bufsize;

        IWL_DEBUG_HT(priv, "Tx aggregation enabled on ra = %pM tid = %d\n",
                 sta->addr, tid);

        return iwl_send_lq_cmd(priv, ctx,
                        &sta_priv->lq_sta.lq, CMD_ASYNC, false);
}

static void iwlagn_check_ratid_empty(struct iwl_priv *priv, int sta_id, u8 tid)
{
        struct iwl_tid_data *tid_data = &priv->tid_data[sta_id][tid];
        enum iwl_rxon_context_id ctx;
        struct ieee80211_vif *vif;
        u8 *addr;

        lockdep_assert_held(&priv->sta_lock);

        addr = priv->stations[sta_id].sta.sta.addr;
        ctx = priv->stations[sta_id].ctxid;
        vif = priv->contexts[ctx].vif;

        switch (priv->tid_data[sta_id][tid].agg.state) {
        case IWL_EMPTYING_HW_QUEUE_DELBA:
                /* There are no packets for this RA / TID in the HW any more */
                if (tid_data->agg.ssn == tid_data->next_reclaimed) {
                        IWL_DEBUG_TX_QUEUES(priv,
                                "Can continue DELBA flow ssn = next_recl = %d\n",
                                tid_data->next_reclaimed);
                        iwl_trans_txq_disable(priv->trans,
                                              tid_data->agg.txq_id, true);
                        iwlagn_dealloc_agg_txq(priv, tid_data->agg.txq_id);
                        tid_data->agg.state = IWL_AGG_OFF;
                        ieee80211_stop_tx_ba_cb_irqsafe(vif, addr, tid);
                }
                break;
        case IWL_EMPTYING_HW_QUEUE_ADDBA:
                /* There are no packets for this RA / TID in the HW any more */
                if (tid_data->agg.ssn == tid_data->next_reclaimed) {
                        IWL_DEBUG_TX_QUEUES(priv,
                                "Can continue ADDBA flow ssn = next_recl = %d\n",
                                tid_data->next_reclaimed);
                        tid_data->agg.state = IWL_AGG_STARTING;
                        ieee80211_start_tx_ba_cb_irqsafe(vif, addr, tid);
                }
                break;
        default:
                break;
        }
}

static void iwlagn_non_agg_tx_status(struct iwl_priv *priv,
                                     struct iwl_rxon_context *ctx,
                                     const u8 *addr1)
{
        struct ieee80211_sta *sta;
        struct iwl_station_priv *sta_priv;

        rcu_read_lock();
        sta = ieee80211_find_sta(ctx->vif, addr1);
        if (sta) {
                sta_priv = (void *)sta->drv_priv;
                /* avoid atomic ops if this isn't a client */
                if (sta_priv->client &&
                    atomic_dec_return(&sta_priv->pending_frames) == 0)
                        ieee80211_sta_block_awake(priv->hw, sta, false);
        }
        rcu_read_unlock();
}

/**
 * translate ucode response to mac80211 tx status control values
 */
static void iwlagn_hwrate_to_tx_control(struct iwl_priv *priv, u32 rate_n_flags,
                                  struct ieee80211_tx_info *info)
{
        struct ieee80211_tx_rate *r = &info->status.rates[0];

        info->status.antenna =
                ((rate_n_flags & RATE_MCS_ANT_ABC_MSK) >> RATE_MCS_ANT_POS);
        if (rate_n_flags & RATE_MCS_HT_MSK)
                r->flags |= IEEE80211_TX_RC_MCS;
        if (rate_n_flags & RATE_MCS_GF_MSK)
                r->flags |= IEEE80211_TX_RC_GREEN_FIELD;
        if (rate_n_flags & RATE_MCS_HT40_MSK)
                r->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
        if (rate_n_flags & RATE_MCS_DUP_MSK)
                r->flags |= IEEE80211_TX_RC_DUP_DATA;
        if (rate_n_flags & RATE_MCS_SGI_MSK)
                r->flags |= IEEE80211_TX_RC_SHORT_GI;
        r->idx = iwlagn_hwrate_to_mac80211_idx(rate_n_flags, info->band);
}

#ifdef CONFIG_IWLWIFI_DEBUG
const char *iwl_get_tx_fail_reason(u32 status)
{
#define TX_STATUS_FAIL(x) case TX_STATUS_FAIL_ ## x: return #x
#define TX_STATUS_POSTPONE(x) case TX_STATUS_POSTPONE_ ## x: return #x

        switch (status & TX_STATUS_MSK) {
        case TX_STATUS_SUCCESS:
                return "SUCCESS";
        TX_STATUS_POSTPONE(DELAY);
        TX_STATUS_POSTPONE(FEW_BYTES);
        TX_STATUS_POSTPONE(BT_PRIO);
        TX_STATUS_POSTPONE(QUIET_PERIOD);
        TX_STATUS_POSTPONE(CALC_TTAK);
        TX_STATUS_FAIL(INTERNAL_CROSSED_RETRY);
        TX_STATUS_FAIL(SHORT_LIMIT);
        TX_STATUS_FAIL(LONG_LIMIT);
        TX_STATUS_FAIL(FIFO_UNDERRUN);
        TX_STATUS_FAIL(DRAIN_FLOW);
        TX_STATUS_FAIL(RFKILL_FLUSH);
        TX_STATUS_FAIL(LIFE_EXPIRE);
        TX_STATUS_FAIL(DEST_PS);
        TX_STATUS_FAIL(HOST_ABORTED);
        TX_STATUS_FAIL(BT_RETRY);
        TX_STATUS_FAIL(STA_INVALID);
        TX_STATUS_FAIL(FRAG_DROPPED);
        TX_STATUS_FAIL(TID_DISABLE);
        TX_STATUS_FAIL(FIFO_FLUSHED);
        TX_STATUS_FAIL(INSUFFICIENT_CF_POLL);
        TX_STATUS_FAIL(PASSIVE_NO_RX);
        TX_STATUS_FAIL(NO_BEACON_ON_RADAR);
        }

        return "UNKNOWN";

#undef TX_STATUS_FAIL
#undef TX_STATUS_POSTPONE
}
#endif /* CONFIG_IWLWIFI_DEBUG */

static void iwlagn_count_agg_tx_err_status(struct iwl_priv *priv, u16 status)
{
        status &= AGG_TX_STATUS_MSK;

        switch (status) {
        case AGG_TX_STATE_UNDERRUN_MSK:
                priv->reply_agg_tx_stats.underrun++;
                break;
        case AGG_TX_STATE_BT_PRIO_MSK:
                priv->reply_agg_tx_stats.bt_prio++;
                break;
        case AGG_TX_STATE_FEW_BYTES_MSK:
                priv->reply_agg_tx_stats.few_bytes++;
                break;
        case AGG_TX_STATE_ABORT_MSK:
                priv->reply_agg_tx_stats.abort++;
                break;
        case AGG_TX_STATE_LAST_SENT_TTL_MSK:
                priv->reply_agg_tx_stats.last_sent_ttl++;
                break;
        case AGG_TX_STATE_LAST_SENT_TRY_CNT_MSK:
                priv->reply_agg_tx_stats.last_sent_try++;
                break;
        case AGG_TX_STATE_LAST_SENT_BT_KILL_MSK:
                priv->reply_agg_tx_stats.last_sent_bt_kill++;
                break;
        case AGG_TX_STATE_SCD_QUERY_MSK:
                priv->reply_agg_tx_stats.scd_query++;
                break;
        case AGG_TX_STATE_TEST_BAD_CRC32_MSK:
                priv->reply_agg_tx_stats.bad_crc32++;
                break;
        case AGG_TX_STATE_RESPONSE_MSK:
                priv->reply_agg_tx_stats.response++;
                break;
        case AGG_TX_STATE_DUMP_TX_MSK:
                priv->reply_agg_tx_stats.dump_tx++;
                break;
        case AGG_TX_STATE_DELAY_TX_MSK:
                priv->reply_agg_tx_stats.delay_tx++;
                break;
        default:
                priv->reply_agg_tx_stats.unknown++;
                break;
        }
}

static inline u32 iwlagn_get_scd_ssn(struct iwlagn_tx_resp *tx_resp)
{
        return le32_to_cpup((__le32 *)&tx_resp->status +
                            tx_resp->frame_count) & IEEE80211_MAX_SN;
}

static void iwl_rx_reply_tx_agg(struct iwl_priv *priv,
                                struct iwlagn_tx_resp *tx_resp)
{
        struct agg_tx_status *frame_status = &tx_resp->status;
        int tid = (tx_resp->ra_tid & IWLAGN_TX_RES_TID_MSK) >>
                IWLAGN_TX_RES_TID_POS;
        int sta_id = (tx_resp->ra_tid & IWLAGN_TX_RES_RA_MSK) >>
                IWLAGN_TX_RES_RA_POS;
        struct iwl_ht_agg *agg = &priv->tid_data[sta_id][tid].agg;
        u32 status = le16_to_cpu(tx_resp->status.status);
        int i;

        WARN_ON(tid == IWL_TID_NON_QOS);

        if (agg->wait_for_ba)
                IWL_DEBUG_TX_REPLY(priv,
                        "got tx response w/o block-ack\n");

        agg->rate_n_flags = le32_to_cpu(tx_resp->rate_n_flags);
        agg->wait_for_ba = (tx_resp->frame_count > 1);

        /*
         * If the BT kill count is non-zero, we'll get this
         * notification again.
         */
        if (tx_resp->bt_kill_count && tx_resp->frame_count == 1 &&
            priv->lib->bt_params &&
            priv->lib->bt_params->advanced_bt_coexist) {
                IWL_DEBUG_COEX(priv, "receive reply tx w/ bt_kill\n");
        }

        if (tx_resp->frame_count == 1)
                return;

        IWL_DEBUG_TX_REPLY(priv, "TXQ %d initial_rate 0x%x ssn %d frm_cnt %d\n",
                           agg->txq_id,
                           le32_to_cpu(tx_resp->rate_n_flags),
                           iwlagn_get_scd_ssn(tx_resp), tx_resp->frame_count);

        /* Construct bit-map of pending frames within Tx window */
        for (i = 0; i < tx_resp->frame_count; i++) {
                u16 fstatus = le16_to_cpu(frame_status[i].status);
                u8 retry_cnt = (fstatus & AGG_TX_TRY_MSK) >> AGG_TX_TRY_POS;

                if (status & AGG_TX_STATUS_MSK)
                        iwlagn_count_agg_tx_err_status(priv, fstatus);

                if (status & (AGG_TX_STATE_FEW_BYTES_MSK |
                              AGG_TX_STATE_ABORT_MSK))
                        continue;

                if (status & AGG_TX_STATUS_MSK || retry_cnt > 1)
                        IWL_DEBUG_TX_REPLY(priv,
                                           "%d: status %s (0x%04x), try-count (0x%01x)\n",
                                           i,
                                           iwl_get_agg_tx_fail_reason(fstatus),
                                           fstatus & AGG_TX_STATUS_MSK,
                                           retry_cnt);
        }
}

#ifdef CONFIG_IWLWIFI_DEBUG
#define AGG_TX_STATE_FAIL(x) case AGG_TX_STATE_ ## x: return #x

const char *iwl_get_agg_tx_fail_reason(u16 status)
{
        status &= AGG_TX_STATUS_MSK;
        switch (status) {
        case AGG_TX_STATE_TRANSMITTED:
                return "SUCCESS";
                AGG_TX_STATE_FAIL(UNDERRUN_MSK);
                AGG_TX_STATE_FAIL(BT_PRIO_MSK);
                AGG_TX_STATE_FAIL(FEW_BYTES_MSK);
                AGG_TX_STATE_FAIL(ABORT_MSK);
                AGG_TX_STATE_FAIL(LAST_SENT_TTL_MSK);
                AGG_TX_STATE_FAIL(LAST_SENT_TRY_CNT_MSK);
                AGG_TX_STATE_FAIL(LAST_SENT_BT_KILL_MSK);
                AGG_TX_STATE_FAIL(SCD_QUERY_MSK);
                AGG_TX_STATE_FAIL(TEST_BAD_CRC32_MSK);
                AGG_TX_STATE_FAIL(RESPONSE_MSK);
                AGG_TX_STATE_FAIL(DUMP_TX_MSK);
                AGG_TX_STATE_FAIL(DELAY_TX_MSK);
        }

        return "UNKNOWN";
}
#endif /* CONFIG_IWLWIFI_DEBUG */

static void iwlagn_count_tx_err_status(struct iwl_priv *priv, u16 status)
{
        status &= TX_STATUS_MSK;

        switch (status) {
        case TX_STATUS_POSTPONE_DELAY:
                priv->reply_tx_stats.pp_delay++;
                break;
        case TX_STATUS_POSTPONE_FEW_BYTES:
                priv->reply_tx_stats.pp_few_bytes++;
                break;
        case TX_STATUS_POSTPONE_BT_PRIO:
                priv->reply_tx_stats.pp_bt_prio++;
                break;
        case TX_STATUS_POSTPONE_QUIET_PERIOD:
                priv->reply_tx_stats.pp_quiet_period++;
                break;
        case TX_STATUS_POSTPONE_CALC_TTAK:
                priv->reply_tx_stats.pp_calc_ttak++;
                break;
        case TX_STATUS_FAIL_INTERNAL_CROSSED_RETRY:
                priv->reply_tx_stats.int_crossed_retry++;
                break;
        case TX_STATUS_FAIL_SHORT_LIMIT:
                priv->reply_tx_stats.short_limit++;
                break;
        case TX_STATUS_FAIL_LONG_LIMIT:
                priv->reply_tx_stats.long_limit++;
                break;
        case TX_STATUS_FAIL_FIFO_UNDERRUN:
                priv->reply_tx_stats.fifo_underrun++;
                break;
        case TX_STATUS_FAIL_DRAIN_FLOW:
                priv->reply_tx_stats.drain_flow++;
                break;
        case TX_STATUS_FAIL_RFKILL_FLUSH:
                priv->reply_tx_stats.rfkill_flush++;
                break;
        case TX_STATUS_FAIL_LIFE_EXPIRE:
                priv->reply_tx_stats.life_expire++;
                break;
        case TX_STATUS_FAIL_DEST_PS:
                priv->reply_tx_stats.dest_ps++;
                break;
        case TX_STATUS_FAIL_HOST_ABORTED:
                priv->reply_tx_stats.host_abort++;
                break;
        case TX_STATUS_FAIL_BT_RETRY:
                priv->reply_tx_stats.bt_retry++;
                break;
        case TX_STATUS_FAIL_STA_INVALID:
                priv->reply_tx_stats.sta_invalid++;
                break;
        case TX_STATUS_FAIL_FRAG_DROPPED:
                priv->reply_tx_stats.frag_drop++;
                break;
        case TX_STATUS_FAIL_TID_DISABLE:
                priv->reply_tx_stats.tid_disable++;
                break;
        case TX_STATUS_FAIL_FIFO_FLUSHED:
                priv->reply_tx_stats.fifo_flush++;
                break;
        case TX_STATUS_FAIL_INSUFFICIENT_CF_POLL:
                priv->reply_tx_stats.insuff_cf_poll++;
                break;
        case TX_STATUS_FAIL_PASSIVE_NO_RX:
                priv->reply_tx_stats.fail_hw_drop++;
                break;
        case TX_STATUS_FAIL_NO_BEACON_ON_RADAR:
                priv->reply_tx_stats.sta_color_mismatch++;
                break;
        default:
                priv->reply_tx_stats.unknown++;
                break;
        }
}

static void iwlagn_set_tx_status(struct iwl_priv *priv,
                                 struct ieee80211_tx_info *info,
                                 struct iwlagn_tx_resp *tx_resp)
{
        u16 status = le16_to_cpu(tx_resp->status.status);

        info->flags &= ~IEEE80211_TX_CTL_AMPDU;

        info->status.rates[0].count = tx_resp->failure_frame + 1;
        info->flags |= iwl_tx_status_to_mac80211(status);
        iwlagn_hwrate_to_tx_control(priv, le32_to_cpu(tx_resp->rate_n_flags),
                                    info);
        if (!iwl_is_tx_success(status))
                iwlagn_count_tx_err_status(priv, status);
}

static void iwl_check_abort_status(struct iwl_priv *priv,
                            u8 frame_count, u32 status)
{
        if (frame_count == 1 && status == TX_STATUS_FAIL_RFKILL_FLUSH) {
                IWL_ERR(priv, "Tx flush command to flush out all frames\n");
                if (!test_bit(STATUS_EXIT_PENDING, &priv->status))
                        queue_work(priv->workqueue, &priv->tx_flush);
        }
}

void iwlagn_rx_reply_tx(struct iwl_priv *priv, struct iwl_rx_cmd_buffer *rxb)
{
        struct iwl_rx_packet *pkt = rxb_addr(rxb);
        u16 sequence = le16_to_cpu(pkt->hdr.sequence);
        int txq_id = SEQ_TO_QUEUE(sequence);
        int cmd_index __maybe_unused = SEQ_TO_INDEX(sequence);
        struct iwlagn_tx_resp *tx_resp = (void *)pkt->data;
        struct ieee80211_hdr *hdr;
        u32 status = le16_to_cpu(tx_resp->status.status);
        u16 ssn = iwlagn_get_scd_ssn(tx_resp);
        int tid;
        int sta_id;
        int freed;
        struct ieee80211_tx_info *info;
        struct sk_buff_head skbs;
        struct sk_buff *skb;
        struct iwl_rxon_context *ctx;
        bool is_agg = (txq_id >= IWLAGN_FIRST_AMPDU_QUEUE);

        tid = (tx_resp->ra_tid & IWLAGN_TX_RES_TID_MSK) >>
                IWLAGN_TX_RES_TID_POS;
        sta_id = (tx_resp->ra_tid & IWLAGN_TX_RES_RA_MSK) >>
                IWLAGN_TX_RES_RA_POS;

        spin_lock_bh(&priv->sta_lock);

        if (is_agg) {
                WARN_ON_ONCE(sta_id >= IWLAGN_STATION_COUNT ||
                             tid >= IWL_MAX_TID_COUNT);
                if (txq_id != priv->tid_data[sta_id][tid].agg.txq_id)
                        IWL_ERR(priv, "txq_id mismatch: %d %d\n", txq_id,
                                priv->tid_data[sta_id][tid].agg.txq_id);
                iwl_rx_reply_tx_agg(priv, tx_resp);
        }

        __skb_queue_head_init(&skbs);

        if (tx_resp->frame_count == 1) {
                u16 next_reclaimed = le16_to_cpu(tx_resp->seq_ctl);
                next_reclaimed = IEEE80211_SEQ_TO_SN(next_reclaimed + 0x10);

                if (is_agg) {
                        /* If this is an aggregation queue, we can rely on the
                         * ssn since the wifi sequence number corresponds to
                         * the index in the TFD ring (%256).
                         * The seq_ctl is the sequence control of the packet
                         * to which this Tx response relates. But if there is a
                         * hole in the bitmap of the BA we received, this Tx
                         * response may allow to reclaim the hole and all the
                         * subsequent packets that were already acked.
                         * In that case, seq_ctl != ssn, and the next packet
                         * to be reclaimed will be ssn and not seq_ctl.
                         */
                        next_reclaimed = ssn;
                }

                if (tid != IWL_TID_NON_QOS) {
                        priv->tid_data[sta_id][tid].next_reclaimed =
                                next_reclaimed;
                        IWL_DEBUG_TX_REPLY(priv, "Next reclaimed packet:%d\n",
                                                  next_reclaimed);
                        iwlagn_check_ratid_empty(priv, sta_id, tid);
                }

                iwl_trans_reclaim(priv->trans, txq_id, ssn, &skbs);

                freed = 0;

                /* process frames */
                skb_queue_walk(&skbs, skb) {
                        hdr = (struct ieee80211_hdr *)skb->data;

                        if (!ieee80211_is_data_qos(hdr->frame_control))
                                priv->last_seq_ctl = tx_resp->seq_ctl;

                        info = IEEE80211_SKB_CB(skb);
                        ctx = info->driver_data[0];
                        iwl_trans_free_tx_cmd(priv->trans,
                                              info->driver_data[1]);

                        memset(&info->status, 0, sizeof(info->status));

                        if (status == TX_STATUS_FAIL_PASSIVE_NO_RX &&
                            ctx->vif &&
                            ctx->vif->type == NL80211_IFTYPE_STATION) {
                                /* block and stop all queues */
                                priv->passive_no_rx = true;
                                IWL_DEBUG_TX_QUEUES(priv,
                                        "stop all queues: passive channel\n");
                                ieee80211_stop_queues(priv->hw);

                                IWL_DEBUG_TX_REPLY(priv,
                                           "TXQ %d status %s (0x%08x) "
                                           "rate_n_flags 0x%x retries %d\n",
                                           txq_id,
                                           iwl_get_tx_fail_reason(status),
                                           status,
                                           le32_to_cpu(tx_resp->rate_n_flags),
                                           tx_resp->failure_frame);

                                IWL_DEBUG_TX_REPLY(priv,
                                           "FrameCnt = %d, idx=%d\n",
                                           tx_resp->frame_count, cmd_index);
                        }

                        /* check if BAR is needed */
                        if (is_agg && !iwl_is_tx_success(status))
                                info->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
                        iwlagn_set_tx_status(priv, IEEE80211_SKB_CB(skb),
                                     tx_resp);
                        if (!is_agg)
                                iwlagn_non_agg_tx_status(priv, ctx, hdr->addr1);

                        freed++;
                }

                if (tid != IWL_TID_NON_QOS) {
                        priv->tid_data[sta_id][tid].next_reclaimed =
                                next_reclaimed;
                        IWL_DEBUG_TX_REPLY(priv, "Next reclaimed packet:%d\n",
                                           next_reclaimed);
                }

                if (!is_agg && freed != 1)
                        IWL_ERR(priv, "Q: %d, freed %d\n", txq_id, freed);

                IWL_DEBUG_TX_REPLY(priv, "TXQ %d status %s (0x%08x)\n", txq_id,
                                   iwl_get_tx_fail_reason(status), status);

                IWL_DEBUG_TX_REPLY(priv,
                                   "\t\t\t\tinitial_rate 0x%x retries %d, idx=%d ssn=%d seq_ctl=0x%x\n",
                                   le32_to_cpu(tx_resp->rate_n_flags),
                                   tx_resp->failure_frame,
                                   SEQ_TO_INDEX(sequence), ssn,
                                   le16_to_cpu(tx_resp->seq_ctl));
        }

        iwl_check_abort_status(priv, tx_resp->frame_count, status);
        spin_unlock_bh(&priv->sta_lock);

        while (!skb_queue_empty(&skbs)) {
                skb = __skb_dequeue(&skbs);
                ieee80211_tx_status(priv->hw, skb);
        }
}

/**
 * iwlagn_rx_reply_compressed_ba - Handler for REPLY_COMPRESSED_BA
 *
 * Handles block-acknowledge notification from device, which reports success
 * of frames sent via aggregation.
 */
void iwlagn_rx_reply_compressed_ba(struct iwl_priv *priv,
                                   struct iwl_rx_cmd_buffer *rxb)
{
        struct iwl_rx_packet *pkt = rxb_addr(rxb);
        struct iwl_compressed_ba_resp *ba_resp = (void *)pkt->data;
        struct iwl_ht_agg *agg;
        struct sk_buff_head reclaimed_skbs;
        struct sk_buff *skb;
        int sta_id;
        int tid;
        int freed;

        /* "flow" corresponds to Tx queue */
        u16 scd_flow = le16_to_cpu(ba_resp->scd_flow);

        /* "ssn" is start of block-ack Tx window, corresponds to index
         * (in Tx queue's circular buffer) of first TFD/frame in window */
        u16 ba_resp_scd_ssn = le16_to_cpu(ba_resp->scd_ssn);

        if (scd_flow >= priv->cfg->base_params->num_of_queues) {
                IWL_ERR(priv,
                        "BUG_ON scd_flow is bigger than number of queues\n");
                return;
        }

        sta_id = ba_resp->sta_id;
        tid = ba_resp->tid;
        agg = &priv->tid_data[sta_id][tid].agg;

        spin_lock_bh(&priv->sta_lock);

        if (unlikely(!agg->wait_for_ba)) {
                if (unlikely(ba_resp->bitmap))
                        IWL_ERR(priv, "Received BA when not expected\n");
                spin_unlock_bh(&priv->sta_lock);
                return;
        }

        if (unlikely(scd_flow != agg->txq_id)) {
                /*
                 * FIXME: this is a uCode bug which need to be addressed,
                 * log the information and return for now.
                 * Since it is can possibly happen very often and in order
                 * not to fill the syslog, don't use IWL_ERR or IWL_WARN
                 */
                IWL_DEBUG_TX_QUEUES(priv,
                                    "Bad queue mapping txq_id=%d, agg_txq[sta:%d,tid:%d]=%d\n",
                                    scd_flow, sta_id, tid, agg->txq_id);
                spin_unlock_bh(&priv->sta_lock);
                return;
        }

        __skb_queue_head_init(&reclaimed_skbs);

        /* Release all TFDs before the SSN, i.e. all TFDs in front of
         * block-ack window (we assume that they've been successfully
         * transmitted ... if not, it's too late anyway). */
        iwl_trans_reclaim(priv->trans, scd_flow, ba_resp_scd_ssn,
                          &reclaimed_skbs);

        IWL_DEBUG_TX_REPLY(priv, "REPLY_COMPRESSED_BA [%d] Received from %pM, "
                           "sta_id = %d\n",
                           agg->wait_for_ba,
                           (u8 *) &ba_resp->sta_addr_lo32,
                           ba_resp->sta_id);
        IWL_DEBUG_TX_REPLY(priv, "TID = %d, SeqCtl = %d, bitmap = 0x%llx, "
                           "scd_flow = %d, scd_ssn = %d sent:%d, acked:%d\n",
                           ba_resp->tid, le16_to_cpu(ba_resp->seq_ctl),
                           (unsigned long long)le64_to_cpu(ba_resp->bitmap),
                           scd_flow, ba_resp_scd_ssn, ba_resp->txed,
                           ba_resp->txed_2_done);

        /* Mark that the expected block-ack response arrived */
        agg->wait_for_ba = false;

        /* Sanity check values reported by uCode */
        if (ba_resp->txed_2_done > ba_resp->txed) {
                IWL_DEBUG_TX_REPLY(priv,
                        "bogus sent(%d) and ack(%d) count\n",
                        ba_resp->txed, ba_resp->txed_2_done);
                /*
                 * set txed_2_done = txed,
                 * so it won't impact rate scale
                 */
                ba_resp->txed = ba_resp->txed_2_done;
        }

        priv->tid_data[sta_id][tid].next_reclaimed = ba_resp_scd_ssn;

        iwlagn_check_ratid_empty(priv, sta_id, tid);
        freed = 0;

        skb_queue_walk(&reclaimed_skbs, skb) {
                struct ieee80211_hdr *hdr = (void *)skb->data;
                struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

                if (ieee80211_is_data_qos(hdr->frame_control))
                        freed++;
                else
                        WARN_ON_ONCE(1);

                iwl_trans_free_tx_cmd(priv->trans, info->driver_data[1]);

                memset(&info->status, 0, sizeof(info->status));
                /* Packet was transmitted successfully, failures come as single
                 * frames because before failing a frame the firmware transmits
                 * it without aggregation at least once.
                 */
                info->flags |= IEEE80211_TX_STAT_ACK;

                if (freed == 1) {
                        /* this is the first skb we deliver in this batch */
                        /* put the rate scaling data there */
                        info = IEEE80211_SKB_CB(skb);
                        memset(&info->status, 0, sizeof(info->status));
                        info->flags |= IEEE80211_TX_STAT_AMPDU;
                        info->status.ampdu_ack_len = ba_resp->txed_2_done;
                        info->status.ampdu_len = ba_resp->txed;
                        iwlagn_hwrate_to_tx_control(priv, agg->rate_n_flags,
                                                    info);
                }
        }

        spin_unlock_bh(&priv->sta_lock);

        while (!skb_queue_empty(&reclaimed_skbs)) {
                skb = __skb_dequeue(&reclaimed_skbs);
                ieee80211_tx_status(priv->hw, skb);
        }
}