/******************************************************************************
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
 * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
 * Copyright(c) 2016        Intel Deutschland GmbH
 *
 * 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
 *
 * BSD LICENSE
 *
 * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
 * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *****************************************************************************/
#include <linux/ieee80211.h>
#include <linux/etherdevice.h>
#include <linux/tcp.h>
#include <net/ip.h>

#include "iwl-trans.h"
#include "iwl-eeprom-parse.h"
#include "mvm.h"
#include "sta.h"
#include "fw-dbg.h"

static void
iwl_mvm_bar_check_trigger(struct iwl_mvm *mvm, const u8 *addr,
                          u16 tid, u16 ssn)
{
        struct iwl_fw_dbg_trigger_tlv *trig;
        struct iwl_fw_dbg_trigger_ba *ba_trig;

        if (!iwl_fw_dbg_trigger_enabled(mvm->fw, FW_DBG_TRIGGER_BA))
                return;

        trig = iwl_fw_dbg_get_trigger(mvm->fw, FW_DBG_TRIGGER_BA);
        ba_trig = (void *)trig->data;

        if (!iwl_fw_dbg_trigger_check_stop(mvm, NULL, trig))
                return;

        if (!(le16_to_cpu(ba_trig->tx_bar) & BIT(tid)))
                return;

        iwl_mvm_fw_dbg_collect_trig(mvm, trig,
                                    "BAR sent to %pM, tid %d, ssn %d",
                                    addr, tid, ssn);
}

/*
 * Sets most of the Tx cmd's fields
 */
void iwl_mvm_set_tx_cmd(struct iwl_mvm *mvm, struct sk_buff *skb,
                        struct iwl_tx_cmd *tx_cmd,
                        struct ieee80211_tx_info *info, u8 sta_id)
{
        struct ieee80211_tx_info *skb_info = IEEE80211_SKB_CB(skb);
        struct ieee80211_hdr *hdr = (void *)skb->data;
        __le16 fc = hdr->frame_control;
        u32 tx_flags = le32_to_cpu(tx_cmd->tx_flags);
        u32 len = skb->len + FCS_LEN;
        u8 ac;

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

        if (ieee80211_is_probe_resp(fc))
                tx_flags |= TX_CMD_FLG_TSF;

        if (ieee80211_has_morefrags(fc))
                tx_flags |= TX_CMD_FLG_MORE_FRAG;

        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;
        } else if (ieee80211_is_back_req(fc)) {
                struct ieee80211_bar *bar = (void *)skb->data;
                u16 control = le16_to_cpu(bar->control);
                u16 ssn = le16_to_cpu(bar->start_seq_num);

                tx_flags |= TX_CMD_FLG_ACK | TX_CMD_FLG_BAR;
                tx_cmd->tid_tspec = (control &
                                     IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
                        IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
                WARN_ON_ONCE(tx_cmd->tid_tspec >= IWL_MAX_TID_COUNT);
                iwl_mvm_bar_check_trigger(mvm, bar->ra, tx_cmd->tid_tspec,
                                          ssn);
        } else {
                tx_cmd->tid_tspec = IWL_TID_NON_QOS;
                if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ)
                        tx_flags |= TX_CMD_FLG_SEQ_CTL;
                else
                        tx_flags &= ~TX_CMD_FLG_SEQ_CTL;
        }

        /* Default to 0 (BE) when tid_spec is set to IWL_TID_NON_QOS */
        if (tx_cmd->tid_tspec < IWL_MAX_TID_COUNT)
                ac = tid_to_mac80211_ac[tx_cmd->tid_tspec];
        else
                ac = tid_to_mac80211_ac[0];

        tx_flags |= iwl_mvm_bt_coex_tx_prio(mvm, hdr, info, ac) <<
                        TX_CMD_FLG_BT_PRIO_POS;

        if (ieee80211_is_mgmt(fc)) {
                if (ieee80211_is_assoc_req(fc) || ieee80211_is_reassoc_req(fc))
                        tx_cmd->pm_frame_timeout = cpu_to_le16(PM_FRAME_ASSOC);
                else if (ieee80211_is_action(fc))
                        tx_cmd->pm_frame_timeout = cpu_to_le16(PM_FRAME_NONE);
                else
                        tx_cmd->pm_frame_timeout = cpu_to_le16(PM_FRAME_MGMT);

                /* The spec allows Action frames in A-MPDU, we don't support
                 * it
                 */
                WARN_ON_ONCE(info->flags & IEEE80211_TX_CTL_AMPDU);
        } else if (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO) {
                tx_cmd->pm_frame_timeout = cpu_to_le16(PM_FRAME_MGMT);
        } else {
                tx_cmd->pm_frame_timeout = cpu_to_le16(PM_FRAME_NONE);
        }

        if (ieee80211_is_data(fc) && len > mvm->rts_threshold &&
            !is_multicast_ether_addr(ieee80211_get_DA(hdr)))
                tx_flags |= TX_CMD_FLG_PROT_REQUIRE;

        if (fw_has_capa(&mvm->fw->ucode_capa,
                        IWL_UCODE_TLV_CAPA_TXPOWER_INSERTION_SUPPORT) &&
            ieee80211_action_contains_tpc(skb))
                tx_flags |= TX_CMD_FLG_WRITE_TX_POWER;

        tx_cmd->tx_flags = cpu_to_le32(tx_flags);
        /* Total # bytes to be transmitted */
        tx_cmd->len = cpu_to_le16((u16)skb->len +
                (uintptr_t)skb_info->driver_data[0]);
        tx_cmd->next_frame_len = 0;
        tx_cmd->life_time = cpu_to_le32(TX_CMD_LIFE_TIME_INFINITE);
        tx_cmd->sta_id = sta_id;
}

/*
 * Sets the fields in the Tx cmd that are rate related
 */
void iwl_mvm_set_tx_cmd_rate(struct iwl_mvm *mvm, struct iwl_tx_cmd *tx_cmd,
                            struct ieee80211_tx_info *info,
                            struct ieee80211_sta *sta, __le16 fc)
{
        u32 rate_flags;
        int rate_idx;
        u8 rate_plcp;

        /* Set retry limit on RTS packets */
        tx_cmd->rts_retry_limit = IWL_RTS_DFAULT_RETRY_LIMIT;

        /* Set retry limit on DATA packets and Probe Responses*/
        if (ieee80211_is_probe_resp(fc)) {
                tx_cmd->data_retry_limit = IWL_MGMT_DFAULT_RETRY_LIMIT;
                tx_cmd->rts_retry_limit =
                        min(tx_cmd->data_retry_limit, tx_cmd->rts_retry_limit);
        } else if (ieee80211_is_back_req(fc)) {
                tx_cmd->data_retry_limit = IWL_BAR_DFAULT_RETRY_LIMIT;
        } else {
                tx_cmd->data_retry_limit = IWL_DEFAULT_TX_RETRY;
        }

        /*
         * for data packets, rate info comes from the table inside the fw. This
         * table is controlled by LINK_QUALITY commands
         */

        if (ieee80211_is_data(fc) && sta) {
                tx_cmd->initial_rate_index = 0;
                tx_cmd->tx_flags |= cpu_to_le32(TX_CMD_FLG_STA_RATE);
                return;
        } else if (ieee80211_is_back_req(fc)) {
                tx_cmd->tx_flags |=
                        cpu_to_le32(TX_CMD_FLG_ACK | TX_CMD_FLG_BAR);
        }

        /* HT rate doesn't make sense for a non data frame */
        WARN_ONCE(info->control.rates[0].flags & IEEE80211_TX_RC_MCS,
                  "Got an HT rate (flags:0x%x/mcs:%d) for a non data frame (fc:0x%x)\n",
                  info->control.rates[0].flags,
                  info->control.rates[0].idx,
                  le16_to_cpu(fc));

        rate_idx = info->control.rates[0].idx;
        /* if the rate isn't a well known legacy rate, take the lowest one */
        if (rate_idx < 0 || rate_idx > IWL_RATE_COUNT_LEGACY)
                rate_idx = rate_lowest_index(
                                &mvm->nvm_data->bands[info->band], sta);

        /* For 5 GHZ band, remap mac80211 rate indices into driver indices */
        if (info->band == IEEE80211_BAND_5GHZ)
                rate_idx += IWL_FIRST_OFDM_RATE;

        /* For 2.4 GHZ band, check that there is no need to remap */
        BUILD_BUG_ON(IWL_FIRST_CCK_RATE != 0);

        /* Get PLCP rate for tx_cmd->rate_n_flags */
        rate_plcp = iwl_mvm_mac80211_idx_to_hwrate(rate_idx);

        mvm->mgmt_last_antenna_idx =
                iwl_mvm_next_antenna(mvm, iwl_mvm_get_valid_tx_ant(mvm),
                                     mvm->mgmt_last_antenna_idx);

        if (info->band == IEEE80211_BAND_2GHZ &&
            !iwl_mvm_bt_coex_is_shared_ant_avail(mvm))
                rate_flags = mvm->cfg->non_shared_ant << RATE_MCS_ANT_POS;
        else
                rate_flags =
                        BIT(mvm->mgmt_last_antenna_idx) << RATE_MCS_ANT_POS;

        /* 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 the rate in the TX cmd */
        tx_cmd->rate_n_flags = cpu_to_le32((u32)rate_plcp | rate_flags);
}

/*
 * Sets the fields in the Tx cmd that are crypto related
 */
static void iwl_mvm_set_tx_cmd_crypto(struct iwl_mvm *mvm,
                                      struct ieee80211_tx_info *info,
                                      struct iwl_tx_cmd *tx_cmd,
                                      struct sk_buff *skb_frag,
                                      int hdrlen)
{
        struct ieee80211_key_conf *keyconf = info->control.hw_key;
        u8 *crypto_hdr = skb_frag->data + hdrlen;
        u64 pn;

        switch (keyconf->cipher) {
        case WLAN_CIPHER_SUITE_CCMP:
        case WLAN_CIPHER_SUITE_CCMP_256:
                iwl_mvm_set_tx_cmd_ccmp(info, tx_cmd);
                pn = atomic64_inc_return(&keyconf->tx_pn);
                crypto_hdr[0] = pn;
                crypto_hdr[2] = 0;
                crypto_hdr[3] = 0x20 | (keyconf->keyidx << 6);
                crypto_hdr[1] = pn >> 8;
                crypto_hdr[4] = pn >> 16;
                crypto_hdr[5] = pn >> 24;
                crypto_hdr[6] = pn >> 32;
                crypto_hdr[7] = pn >> 40;
                break;

        case WLAN_CIPHER_SUITE_TKIP:
                tx_cmd->sec_ctl = TX_CMD_SEC_TKIP;
                pn = atomic64_inc_return(&keyconf->tx_pn);
                ieee80211_tkip_add_iv(crypto_hdr, keyconf, pn);
                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_WEP_KEY_IDX_POS) &
                          TX_CMD_SEC_WEP_KEY_IDX_MSK);

                memcpy(&tx_cmd->key[3], keyconf->key, keyconf->keylen);
                break;
        default:
                tx_cmd->sec_ctl |= TX_CMD_SEC_EXT;
        }
}

/*
 * Allocates and sets the Tx cmd the driver data pointers in the skb
 */
static struct iwl_device_cmd *
iwl_mvm_set_tx_params(struct iwl_mvm *mvm, struct sk_buff *skb,
                      struct ieee80211_tx_info *info, int hdrlen,
                      struct ieee80211_sta *sta, u8 sta_id)
{
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        struct ieee80211_tx_info *skb_info = IEEE80211_SKB_CB(skb);
        struct iwl_device_cmd *dev_cmd;
        struct iwl_tx_cmd *tx_cmd;

        dev_cmd = iwl_trans_alloc_tx_cmd(mvm->trans);

        if (unlikely(!dev_cmd))
                return NULL;

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

        if (info->control.hw_key)
                iwl_mvm_set_tx_cmd_crypto(mvm, info, tx_cmd, skb, hdrlen);

        iwl_mvm_set_tx_cmd(mvm, skb, tx_cmd, info, sta_id);

        iwl_mvm_set_tx_cmd_rate(mvm, tx_cmd, info, sta, hdr->frame_control);

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

        skb_info->driver_data[1] = dev_cmd;

        return dev_cmd;
}

int iwl_mvm_tx_skb_non_sta(struct iwl_mvm *mvm, struct sk_buff *skb)
{
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        struct ieee80211_tx_info *skb_info = IEEE80211_SKB_CB(skb);
        struct ieee80211_tx_info info;
        struct iwl_device_cmd *dev_cmd;
        struct iwl_tx_cmd *tx_cmd;
        u8 sta_id;
        int hdrlen = ieee80211_hdrlen(hdr->frame_control);

        memcpy(&info, skb->cb, sizeof(info));

        if (WARN_ON_ONCE(info.flags & IEEE80211_TX_CTL_AMPDU))
                return -1;

        if (WARN_ON_ONCE(info.flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM &&
                         (!info.control.vif ||
                          info.hw_queue != info.control.vif->cab_queue)))
                return -1;

        /* This holds the amsdu headers length */
        skb_info->driver_data[0] = (void *)(uintptr_t)0;

        /*
         * IWL_MVM_OFFCHANNEL_QUEUE is used for ROC packets that can be used
         * in 2 different types of vifs, P2P & STATION. P2P uses the offchannel
         * queue. STATION (HS2.0) uses the auxiliary context of the FW,
         * and hence needs to be sent on the aux queue
         */
        if (IEEE80211_SKB_CB(skb)->hw_queue == IWL_MVM_OFFCHANNEL_QUEUE &&
            info.control.vif->type == NL80211_IFTYPE_STATION)
                IEEE80211_SKB_CB(skb)->hw_queue = mvm->aux_queue;

        /*
         * If the interface on which the frame is sent is the P2P_DEVICE
         * or an AP/GO interface use the broadcast station associated
         * with it; otherwise if the interface is a managed interface
         * use the AP station associated with it for multicast traffic
         * (this is not possible for unicast packets as a TLDS discovery
         * response are sent without a station entry); otherwise use the
         * AUX station.
         */
        sta_id = mvm->aux_sta.sta_id;
        if (info.control.vif) {
                struct iwl_mvm_vif *mvmvif =
                        iwl_mvm_vif_from_mac80211(info.control.vif);

                if (info.control.vif->type == NL80211_IFTYPE_P2P_DEVICE ||
                    info.control.vif->type == NL80211_IFTYPE_AP)
                        sta_id = mvmvif->bcast_sta.sta_id;
                else if (info.control.vif->type == NL80211_IFTYPE_STATION &&
                         is_multicast_ether_addr(hdr->addr1)) {
                        u8 ap_sta_id = ACCESS_ONCE(mvmvif->ap_sta_id);

                        if (ap_sta_id != IWL_MVM_STATION_COUNT)
                                sta_id = ap_sta_id;
                }
        }

        IWL_DEBUG_TX(mvm, "station Id %d, queue=%d\n", sta_id, info.hw_queue);

        dev_cmd = iwl_mvm_set_tx_params(mvm, skb, &info, hdrlen, NULL, sta_id);
        if (!dev_cmd)
                return -1;

        tx_cmd = (struct iwl_tx_cmd *)dev_cmd->payload;

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

        if (iwl_trans_tx(mvm->trans, skb, dev_cmd, info.hw_queue)) {
                iwl_trans_free_tx_cmd(mvm->trans, dev_cmd);
                return -1;
        }

        /*
         * Increase the pending frames counter, so that later when a reply comes
         * in and the counter is decreased - we don't start getting negative
         * values.
         * Note that we don't need to make sure it isn't agg'd, since we're
         * TXing non-sta
         */
        atomic_inc(&mvm->pending_frames[sta_id]);

        return 0;
}

#ifdef CONFIG_INET
static int iwl_mvm_tx_tso(struct iwl_mvm *mvm, struct sk_buff *skb,
                          struct ieee80211_tx_info *info,
                          struct ieee80211_sta *sta,
                          struct sk_buff_head *mpdus_skb)
{
        struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
        struct ieee80211_hdr *hdr = (void *)skb->data;
        unsigned int mss = skb_shinfo(skb)->gso_size;
        struct sk_buff *tmp, *next;
        char cb[sizeof(skb->cb)];
        unsigned int num_subframes, tcp_payload_len, subf_len, max_amsdu_len;
        bool ipv4 = (skb->protocol == htons(ETH_P_IP));
        u16 ip_base_id = ipv4 ? ntohs(ip_hdr(skb)->id) : 0;
        u16 amsdu_add, snap_ip_tcp, pad, i = 0;
        unsigned int dbg_max_amsdu_len;
        u8 *qc, tid, txf;

        snap_ip_tcp = 8 + skb_transport_header(skb) - skb_network_header(skb) +
                tcp_hdrlen(skb);

        qc = ieee80211_get_qos_ctl(hdr);
        tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
        if (WARN_ON_ONCE(tid >= IWL_MAX_TID_COUNT))
                return -EINVAL;

        if (!sta->max_amsdu_len ||
            !ieee80211_is_data_qos(hdr->frame_control) ||
            !mvmsta->tlc_amsdu) {
                num_subframes = 1;
                pad = 0;
                goto segment;
        }

        /*
         * No need to lock amsdu_in_ampdu_allowed since it can't be modified
         * during an BA session.
         */
        if (info->flags & IEEE80211_TX_CTL_AMPDU &&
            !mvmsta->tid_data[tid].amsdu_in_ampdu_allowed) {
                num_subframes = 1;
                pad = 0;
                goto segment;
        }

        max_amsdu_len = sta->max_amsdu_len;
        dbg_max_amsdu_len = ACCESS_ONCE(mvm->max_amsdu_len);

        /* the Tx FIFO to which this A-MSDU will be routed */
        txf = iwl_mvm_ac_to_tx_fifo[tid_to_mac80211_ac[tid]];

        /*
         * Don't send an AMSDU that will be longer than the TXF.
         * Add a security margin of 256 for the TX command + headers.
         * We also want to have the start of the next packet inside the
         * fifo to be able to send bursts.
         */
        max_amsdu_len = min_t(unsigned int, max_amsdu_len,
                              mvm->shared_mem_cfg.txfifo_size[txf] - 256);

        if (dbg_max_amsdu_len)
                max_amsdu_len = min_t(unsigned int, max_amsdu_len,
                                      dbg_max_amsdu_len);

        /*
         * Limit A-MSDU in A-MPDU to 4095 bytes when VHT is not
         * supported. This is a spec requirement (IEEE 802.11-2015
         * section 8.7.3 NOTE 3).
         */
        if (info->flags & IEEE80211_TX_CTL_AMPDU &&
            !sta->vht_cap.vht_supported)
                max_amsdu_len = min_t(unsigned int, max_amsdu_len, 4095);

        /* Sub frame header + SNAP + IP header + TCP header + MSS */
        subf_len = sizeof(struct ethhdr) + snap_ip_tcp + mss;
        pad = (4 - subf_len) & 0x3;

        /*
         * If we have N subframes in the A-MSDU, then the A-MSDU's size is
         * N * subf_len + (N - 1) * pad.
         */
        num_subframes = (max_amsdu_len + pad) / (subf_len + pad);
        if (num_subframes > 1)
                *qc |= IEEE80211_QOS_CTL_A_MSDU_PRESENT;

        tcp_payload_len = skb_tail_pointer(skb) - skb_transport_header(skb) -
                tcp_hdrlen(skb) + skb->data_len;

        /*
         * Make sure we have enough TBs for the A-MSDU:
         *      2 for each subframe
         *      1 more for each fragment
         *      1 more for the potential data in the header
         */
        num_subframes =
                min_t(unsigned int, num_subframes,
                      (mvm->trans->max_skb_frags - 1 -
                       skb_shinfo(skb)->nr_frags) / 2);

        /* This skb fits in one single A-MSDU */
        if (num_subframes * mss >= tcp_payload_len) {
                struct ieee80211_tx_info *skb_info = IEEE80211_SKB_CB(skb);

                /*
                 * Compute the length of all the data added for the A-MSDU.
                 * This will be used to compute the length to write in the TX
                 * command. We have: SNAP + IP + TCP for n -1 subframes and
                 * ETH header for n subframes. Note that the original skb
                 * already had one set of SNAP / IP / TCP headers.
                 */
                num_subframes = DIV_ROUND_UP(tcp_payload_len, mss);
                amsdu_add = num_subframes * sizeof(struct ethhdr) +
                        (num_subframes - 1) * (snap_ip_tcp + pad);
                /* This holds the amsdu headers length */
                skb_info->driver_data[0] = (void *)(uintptr_t)amsdu_add;

                __skb_queue_tail(mpdus_skb, skb);
                return 0;
        }

        /*
         * Trick the segmentation function to make it
         * create SKBs that can fit into one A-MSDU.
         */
segment:
        skb_shinfo(skb)->gso_size = num_subframes * mss;
        memcpy(cb, skb->cb, sizeof(cb));

        next = skb_gso_segment(skb, NETIF_F_CSUM_MASK | NETIF_F_SG);
        skb_shinfo(skb)->gso_size = mss;
        if (WARN_ON_ONCE(IS_ERR(next)))
                return -EINVAL;
        else if (next)
                consume_skb(skb);

        while (next) {
                tmp = next;
                next = tmp->next;

                memcpy(tmp->cb, cb, sizeof(tmp->cb));
                /*
                 * Compute the length of all the data added for the A-MSDU.
                 * This will be used to compute the length to write in the TX
                 * command. We have: SNAP + IP + TCP for n -1 subframes and
                 * ETH header for n subframes.
                 */
                tcp_payload_len = skb_tail_pointer(tmp) -
                        skb_transport_header(tmp) -
                        tcp_hdrlen(tmp) + tmp->data_len;

                if (ipv4)
                        ip_hdr(tmp)->id = htons(ip_base_id + i * num_subframes);

                if (tcp_payload_len > mss) {
                        struct ieee80211_tx_info *skb_info =
                                IEEE80211_SKB_CB(tmp);

                        num_subframes = DIV_ROUND_UP(tcp_payload_len, mss);
                        amsdu_add = num_subframes * sizeof(struct ethhdr) +
                                (num_subframes - 1) * (snap_ip_tcp + pad);
                        skb_info->driver_data[0] =
                                (void *)(uintptr_t)amsdu_add;
                        skb_shinfo(tmp)->gso_size = mss;
                } else {
                        qc = ieee80211_get_qos_ctl((void *)tmp->data);

                        if (ipv4)
                                ip_send_check(ip_hdr(tmp));
                        *qc &= ~IEEE80211_QOS_CTL_A_MSDU_PRESENT;
                        skb_shinfo(tmp)->gso_size = 0;
                }

                tmp->prev = NULL;
                tmp->next = NULL;

                __skb_queue_tail(mpdus_skb, tmp);
                i++;
        }

        return 0;
}
#else /* CONFIG_INET */
static int iwl_mvm_tx_tso(struct iwl_mvm *mvm, struct sk_buff *skb,
                          struct ieee80211_tx_info *info,
                          struct ieee80211_sta *sta,
                          struct sk_buff_head *mpdus_skb)
{
        /* Impossible to get TSO with CONFIG_INET */
        WARN_ON(1);

        return -1;
}
#endif

/*
 * Sets the fields in the Tx cmd that are crypto related
 */
static int iwl_mvm_tx_mpdu(struct iwl_mvm *mvm, struct sk_buff *skb,
                           struct ieee80211_tx_info *info,
                           struct ieee80211_sta *sta)
{
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
        struct iwl_mvm_sta *mvmsta;
        struct iwl_device_cmd *dev_cmd;
        struct iwl_tx_cmd *tx_cmd;
        __le16 fc;
        u16 seq_number = 0;
        u8 tid = IWL_MAX_TID_COUNT;
        u8 txq_id = info->hw_queue;
        bool is_data_qos = false, is_ampdu = false;
        int hdrlen;

        mvmsta = iwl_mvm_sta_from_mac80211(sta);
        fc = hdr->frame_control;
        hdrlen = ieee80211_hdrlen(fc);

        if (WARN_ON_ONCE(!mvmsta))
                return -1;

        if (WARN_ON_ONCE(mvmsta->sta_id == IWL_MVM_STATION_COUNT))
                return -1;

        dev_cmd = iwl_mvm_set_tx_params(mvm, skb, info, hdrlen,
                                        sta, mvmsta->sta_id);
        if (!dev_cmd)
                goto drop;

        tx_cmd = (struct iwl_tx_cmd *)dev_cmd->payload;
        /* From now on, we cannot access info->control */

        /*
         * we handle that entirely ourselves -- for uAPSD the firmware
         * will always send a notification, and for PS-Poll responses
         * we'll notify mac80211 when getting frame status
         */
        info->flags &= ~IEEE80211_TX_STATUS_EOSP;

        spin_lock(&mvmsta->lock);

        if (ieee80211_is_data_qos(fc) && !ieee80211_is_qos_nullfunc(fc)) {
                u8 *qc = NULL;
                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;

                seq_number = mvmsta->tid_data[tid].seq_number;
                seq_number &= IEEE80211_SCTL_SEQ;
                hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
                hdr->seq_ctrl |= cpu_to_le16(seq_number);
                is_data_qos = true;
                is_ampdu = info->flags & IEEE80211_TX_CTL_AMPDU;
        }

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

        WARN_ON_ONCE(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM);

        if (sta->tdls) {
                /* default to TID 0 for non-QoS packets */
                u8 tdls_tid = tid == IWL_MAX_TID_COUNT ? 0 : tid;

                txq_id = mvmsta->hw_queue[tid_to_mac80211_ac[tdls_tid]];
        }

        if (is_ampdu) {
                if (WARN_ON_ONCE(mvmsta->tid_data[tid].state != IWL_AGG_ON))
                        goto drop_unlock_sta;
                txq_id = mvmsta->tid_data[tid].txq_id;
        }

        IWL_DEBUG_TX(mvm, "TX to [%d|%d] Q:%d - seq: 0x%x\n", mvmsta->sta_id,
                     tid, txq_id, IEEE80211_SEQ_TO_SN(seq_number));

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

        if (is_data_qos && !ieee80211_has_morefrags(fc))
                mvmsta->tid_data[tid].seq_number = seq_number + 0x10;

        spin_unlock(&mvmsta->lock);

        if (txq_id < mvm->first_agg_queue)
                atomic_inc(&mvm->pending_frames[mvmsta->sta_id]);

        return 0;

drop_unlock_sta:
        iwl_trans_free_tx_cmd(mvm->trans, dev_cmd);
        spin_unlock(&mvmsta->lock);
drop:
        return -1;
}

int iwl_mvm_tx_skb(struct iwl_mvm *mvm, struct sk_buff *skb,
                   struct ieee80211_sta *sta)
{
        struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
        struct ieee80211_tx_info *skb_info = IEEE80211_SKB_CB(skb);
        struct ieee80211_tx_info info;
        struct sk_buff_head mpdus_skbs;
        unsigned int payload_len;
        int ret;

        if (WARN_ON_ONCE(!mvmsta))
                return -1;

        if (WARN_ON_ONCE(mvmsta->sta_id == IWL_MVM_STATION_COUNT))
                return -1;

        memcpy(&info, skb->cb, sizeof(info));

        /* This holds the amsdu headers length */
        skb_info->driver_data[0] = (void *)(uintptr_t)0;

        if (!skb_is_gso(skb))
                return iwl_mvm_tx_mpdu(mvm, skb, &info, sta);

        payload_len = skb_tail_pointer(skb) - skb_transport_header(skb) -
                tcp_hdrlen(skb) + skb->data_len;

        if (payload_len <= skb_shinfo(skb)->gso_size)
                return iwl_mvm_tx_mpdu(mvm, skb, &info, sta);

        __skb_queue_head_init(&mpdus_skbs);

        ret = iwl_mvm_tx_tso(mvm, skb, &info, sta, &mpdus_skbs);
        if (ret)
                return ret;

        if (WARN_ON(skb_queue_empty(&mpdus_skbs)))
                return ret;

        while (!skb_queue_empty(&mpdus_skbs)) {
                skb = __skb_dequeue(&mpdus_skbs);

                ret = iwl_mvm_tx_mpdu(mvm, skb, &info, sta);
                if (ret) {
                        __skb_queue_purge(&mpdus_skbs);
                        return ret;
                }
        }

        return 0;
}

static void iwl_mvm_check_ratid_empty(struct iwl_mvm *mvm,
                                      struct ieee80211_sta *sta, u8 tid)
{
        struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
        struct iwl_mvm_tid_data *tid_data = &mvmsta->tid_data[tid];
        struct ieee80211_vif *vif = mvmsta->vif;

        lockdep_assert_held(&mvmsta->lock);

        if ((tid_data->state == IWL_AGG_ON ||
             tid_data->state == IWL_EMPTYING_HW_QUEUE_DELBA) &&
            iwl_mvm_tid_queued(tid_data) == 0) {
                /*
                 * Now that this aggregation queue is empty tell mac80211 so it
                 * knows we no longer have frames buffered for the station on
                 * this TID (for the TIM bitmap calculation.)
                 */
                ieee80211_sta_set_buffered(sta, tid, false);
        }

        if (tid_data->ssn != tid_data->next_reclaimed)
                return;

        switch (tid_data->state) {
        case IWL_EMPTYING_HW_QUEUE_ADDBA:
                IWL_DEBUG_TX_QUEUES(mvm,
                                    "Can continue addBA flow ssn = next_recl = %d\n",
                                    tid_data->next_reclaimed);
                tid_data->state = IWL_AGG_STARTING;
                ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                break;

        case IWL_EMPTYING_HW_QUEUE_DELBA:
                IWL_DEBUG_TX_QUEUES(mvm,
                                    "Can continue DELBA flow ssn = next_recl = %d\n",
                                    tid_data->next_reclaimed);
                iwl_mvm_disable_txq(mvm, tid_data->txq_id,
                                    vif->hw_queue[tid_to_mac80211_ac[tid]], tid,
                                    CMD_ASYNC);
                tid_data->state = IWL_AGG_OFF;
                ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                break;

        default:
                break;
        }
}

#ifdef CONFIG_IWLWIFI_DEBUG
const char *iwl_mvm_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(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(SMALL_CF_POLL);
        TX_STATUS_FAIL(FW_DROP);
        TX_STATUS_FAIL(STA_COLOR_MISMATCH);
        }

        return "UNKNOWN";

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

void iwl_mvm_hwrate_to_tx_rate(u32 rate_n_flags,
                               enum ieee80211_band band,
                               struct ieee80211_tx_rate *r)
{
        if (rate_n_flags & RATE_HT_MCS_GF_MSK)
                r->flags |= IEEE80211_TX_RC_GREEN_FIELD;
        switch (rate_n_flags & RATE_MCS_CHAN_WIDTH_MSK) {
        case RATE_MCS_CHAN_WIDTH_20:
                break;
        case RATE_MCS_CHAN_WIDTH_40:
                r->flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
                break;
        case RATE_MCS_CHAN_WIDTH_80:
                r->flags |= IEEE80211_TX_RC_80_MHZ_WIDTH;
                break;
        case RATE_MCS_CHAN_WIDTH_160:
                r->flags |= IEEE80211_TX_RC_160_MHZ_WIDTH;
                break;
        }
        if (rate_n_flags & RATE_MCS_SGI_MSK)
                r->flags |= IEEE80211_TX_RC_SHORT_GI;
        if (rate_n_flags & RATE_MCS_HT_MSK) {
                r->flags |= IEEE80211_TX_RC_MCS;
                r->idx = rate_n_flags & RATE_HT_MCS_INDEX_MSK;
        } else if (rate_n_flags & RATE_MCS_VHT_MSK) {
                ieee80211_rate_set_vht(
                        r, rate_n_flags & RATE_VHT_MCS_RATE_CODE_MSK,
                        ((rate_n_flags & RATE_VHT_MCS_NSS_MSK) >>
                                                RATE_VHT_MCS_NSS_POS) + 1);
                r->flags |= IEEE80211_TX_RC_VHT_MCS;
        } else {
                r->idx = iwl_mvm_legacy_rate_to_mac80211_idx(rate_n_flags,
                                                             band);
        }
}

/**
 * translate ucode response to mac80211 tx status control values
 */
static void iwl_mvm_hwrate_to_tx_status(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);
        iwl_mvm_hwrate_to_tx_rate(rate_n_flags, info->band, r);
}

static void iwl_mvm_tx_status_check_trigger(struct iwl_mvm *mvm,
                                            u32 status)
{
        struct iwl_fw_dbg_trigger_tlv *trig;
        struct iwl_fw_dbg_trigger_tx_status *status_trig;
        int i;

        if (!iwl_fw_dbg_trigger_enabled(mvm->fw, FW_DBG_TRIGGER_TX_STATUS))
                return;

        trig = iwl_fw_dbg_get_trigger(mvm->fw, FW_DBG_TRIGGER_TX_STATUS);
        status_trig = (void *)trig->data;

        if (!iwl_fw_dbg_trigger_check_stop(mvm, NULL, trig))
                return;

        for (i = 0; i < ARRAY_SIZE(status_trig->statuses); i++) {
                /* don't collect on status 0 */
                if (!status_trig->statuses[i].status)
                        break;

                if (status_trig->statuses[i].status != (status & TX_STATUS_MSK))
                        continue;

                iwl_mvm_fw_dbg_collect_trig(mvm, trig,
                                            "Tx status %d was received",
                                            status & TX_STATUS_MSK);
                break;
        }
}

static void iwl_mvm_rx_tx_cmd_single(struct iwl_mvm *mvm,
                                     struct iwl_rx_packet *pkt)
{
        struct ieee80211_sta *sta;
        u16 sequence = le16_to_cpu(pkt->hdr.sequence);
        int txq_id = SEQ_TO_QUEUE(sequence);
        struct iwl_mvm_tx_resp *tx_resp = (void *)pkt->data;
        int sta_id = IWL_MVM_TX_RES_GET_RA(tx_resp->ra_tid);
        int tid = IWL_MVM_TX_RES_GET_TID(tx_resp->ra_tid);
        u32 status = le16_to_cpu(tx_resp->status.status);
        u16 ssn = iwl_mvm_get_scd_ssn(tx_resp);
        struct iwl_mvm_sta *mvmsta;
        struct sk_buff_head skbs;
        u8 skb_freed = 0;
        u16 next_reclaimed, seq_ctl;
        bool is_ndp = false;

        __skb_queue_head_init(&skbs);

        seq_ctl = le16_to_cpu(tx_resp->seq_ctl);

        /* we can free until ssn % q.n_bd not inclusive */
        iwl_trans_reclaim(mvm->trans, txq_id, ssn, &skbs);

        while (!skb_queue_empty(&skbs)) {
                struct sk_buff *skb = __skb_dequeue(&skbs);
                struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

                skb_freed++;

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

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

                info->flags &= ~IEEE80211_TX_CTL_AMPDU;

                /* inform mac80211 about what happened with the frame */
                switch (status & TX_STATUS_MSK) {
                case TX_STATUS_SUCCESS:
                case TX_STATUS_DIRECT_DONE:
                        info->flags |= IEEE80211_TX_STAT_ACK;
                        break;
                case TX_STATUS_FAIL_DEST_PS:
                        info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
                        break;
                default:
                        break;
                }

                iwl_mvm_tx_status_check_trigger(mvm, status);

                info->status.rates[0].count = tx_resp->failure_frame + 1;
                iwl_mvm_hwrate_to_tx_status(le32_to_cpu(tx_resp->initial_rate),
                                            info);
                info->status.status_driver_data[1] =
                        (void *)(uintptr_t)le32_to_cpu(tx_resp->initial_rate);

                /* Single frame failure in an AMPDU queue => send BAR */
                if (txq_id >= mvm->first_agg_queue &&
                    !(info->flags & IEEE80211_TX_STAT_ACK) &&
                    !(info->flags & IEEE80211_TX_STAT_TX_FILTERED))
                        info->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;

                /* W/A FW bug: seq_ctl is wrong when the status isn't success */
                if (status != TX_STATUS_SUCCESS) {
                        struct ieee80211_hdr *hdr = (void *)skb->data;
                        seq_ctl = le16_to_cpu(hdr->seq_ctrl);
                }

                if (unlikely(!seq_ctl)) {
                        struct ieee80211_hdr *hdr = (void *)skb->data;

                        /*
                         * If it is an NDP, we can't update next_reclaim since
                         * its sequence control is 0. Note that for that same
                         * reason, NDPs are never sent to A-MPDU'able queues
                         * so that we can never have more than one freed frame
                         * for a single Tx resonse (see WARN_ON below).
                         */
                        if (ieee80211_is_qos_nullfunc(hdr->frame_control))
                                is_ndp = true;
                }

                /*
                 * TODO: this is not accurate if we are freeing more than one
                 * packet.
                 */
                info->status.tx_time =
                        le16_to_cpu(tx_resp->wireless_media_time);
                BUILD_BUG_ON(ARRAY_SIZE(info->status.status_driver_data) < 1);
                info->status.status_driver_data[0] =
                                (void *)(uintptr_t)tx_resp->reduced_tpc;

                ieee80211_tx_status(mvm->hw, skb);
        }

        if (txq_id >= mvm->first_agg_queue) {
                /* If this is an aggregation queue, we use the ssn since:
                 * ssn = wifi seq_num % 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. In that
                 * case, several packets will be reclaimed even if
                 * frame_count = 1.
                 *
                 * The ssn is the index (% 256) of the latest packet that has
                 * treated (acked / dropped) + 1.
                 */
                next_reclaimed = ssn;
        } else {
                /* The next packet to be reclaimed is the one after this one */
                next_reclaimed = IEEE80211_SEQ_TO_SN(seq_ctl + 0x10);
        }

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

        IWL_DEBUG_TX_REPLY(mvm,
                           "\t\t\t\tinitial_rate 0x%x retries %d, idx=%d ssn=%d next_reclaimed=0x%x seq_ctl=0x%x\n",
                           le32_to_cpu(tx_resp->initial_rate),
                           tx_resp->failure_frame, SEQ_TO_INDEX(sequence),
                           ssn, next_reclaimed, seq_ctl);

        rcu_read_lock();

        sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]);
        /*
         * sta can't be NULL otherwise it'd mean that the sta has been freed in
         * the firmware while we still have packets for it in the Tx queues.
         */
        if (WARN_ON_ONCE(!sta))
                goto out;

        if (!IS_ERR(sta)) {
                mvmsta = iwl_mvm_sta_from_mac80211(sta);

                if (tid != IWL_TID_NON_QOS) {
                        struct iwl_mvm_tid_data *tid_data =
                                &mvmsta->tid_data[tid];
                        bool send_eosp_ndp = false;

                        spin_lock_bh(&mvmsta->lock);
                        if (!is_ndp) {
                                tid_data->next_reclaimed = next_reclaimed;
                                IWL_DEBUG_TX_REPLY(mvm,
                                                   "Next reclaimed packet:%d\n",
                                                   next_reclaimed);
                        } else {
                                IWL_DEBUG_TX_REPLY(mvm,
                                                   "NDP - don't update next_reclaimed\n");
                        }

                        iwl_mvm_check_ratid_empty(mvm, sta, tid);

                        if (mvmsta->sleep_tx_count) {
                                mvmsta->sleep_tx_count--;
                                if (mvmsta->sleep_tx_count &&
                                    !iwl_mvm_tid_queued(tid_data)) {
                                        /*
                                         * The number of frames in the queue
                                         * dropped to 0 even if we sent less
                                         * frames than we thought we had on the
                                         * Tx queue.
                                         * This means we had holes in the BA
                                         * window that we just filled, ask
                                         * mac80211 to send EOSP since the
                                         * firmware won't know how to do that.
                                         * Send NDP and the firmware will send
                                         * EOSP notification that will trigger
                                         * a call to ieee80211_sta_eosp().
                                         */
                                        send_eosp_ndp = true;
                                }
                        }

                        spin_unlock_bh(&mvmsta->lock);
                        if (send_eosp_ndp) {
                                iwl_mvm_sta_modify_sleep_tx_count(mvm, sta,
                                        IEEE80211_FRAME_RELEASE_UAPSD,
                                        1, tid, false, false);
                                mvmsta->sleep_tx_count = 0;
                                ieee80211_send_eosp_nullfunc(sta, tid);
                        }
                }

                if (mvmsta->next_status_eosp) {
                        mvmsta->next_status_eosp = false;
                        ieee80211_sta_eosp(sta);
                }
        } else {
                mvmsta = NULL;
        }

        /*
         * If the txq is not an AMPDU queue, there is no chance we freed
         * several skbs. Check that out...
         */
        if (txq_id >= mvm->first_agg_queue)
                goto out;

        /* We can't free more than one frame at once on a shared queue */
        WARN_ON(skb_freed > 1);

        /* If we have still frames for this STA nothing to do here */
        if (!atomic_sub_and_test(skb_freed, &mvm->pending_frames[sta_id]))
                goto out;

        if (mvmsta && mvmsta->vif->type == NL80211_IFTYPE_AP) {

                /*
                 * If there are no pending frames for this STA and
                 * the tx to this station is not disabled, notify
                 * mac80211 that this station can now wake up in its
                 * STA table.
                 * If mvmsta is not NULL, sta is valid.
                 */

                spin_lock_bh(&mvmsta->lock);

                if (!mvmsta->disable_tx)
                        ieee80211_sta_block_awake(mvm->hw, sta, false);

                spin_unlock_bh(&mvmsta->lock);
        }

        if (PTR_ERR(sta) == -EBUSY || PTR_ERR(sta) == -ENOENT) {
                /*
                 * We are draining and this was the last packet - pre_rcu_remove
                 * has been called already. We might be after the
                 * synchronize_net already.
                 * Don't rely on iwl_mvm_rm_sta to see the empty Tx queues.
                 */
                set_bit(sta_id, mvm->sta_drained);
                schedule_work(&mvm->sta_drained_wk);
        }

out:
        rcu_read_unlock();
}

#ifdef CONFIG_IWLWIFI_DEBUG
#define AGG_TX_STATE_(x) case AGG_TX_STATE_ ## x: return #x
static const char *iwl_get_agg_tx_status(u16 status)
{
        switch (status & AGG_TX_STATE_STATUS_MSK) {
        AGG_TX_STATE_(TRANSMITTED);
        AGG_TX_STATE_(UNDERRUN);
        AGG_TX_STATE_(BT_PRIO);
        AGG_TX_STATE_(FEW_BYTES);
        AGG_TX_STATE_(ABORT);
        AGG_TX_STATE_(LAST_SENT_TTL);
        AGG_TX_STATE_(LAST_SENT_TRY_CNT);
        AGG_TX_STATE_(LAST_SENT_BT_KILL);
        AGG_TX_STATE_(SCD_QUERY);
        AGG_TX_STATE_(TEST_BAD_CRC32);
        AGG_TX_STATE_(RESPONSE);
        AGG_TX_STATE_(DUMP_TX);
        AGG_TX_STATE_(DELAY_TX);
        }

        return "UNKNOWN";
}

static void iwl_mvm_rx_tx_cmd_agg_dbg(struct iwl_mvm *mvm,
                                      struct iwl_rx_packet *pkt)
{
        struct iwl_mvm_tx_resp *tx_resp = (void *)pkt->data;
        struct agg_tx_status *frame_status = &tx_resp->status;
        int i;

        for (i = 0; i < tx_resp->frame_count; i++) {
                u16 fstatus = le16_to_cpu(frame_status[i].status);

                IWL_DEBUG_TX_REPLY(mvm,
                                   "status %s (0x%04x), try-count (%d) seq (0x%x)\n",
                                   iwl_get_agg_tx_status(fstatus),
                                   fstatus & AGG_TX_STATE_STATUS_MSK,
                                   (fstatus & AGG_TX_STATE_TRY_CNT_MSK) >>
                                        AGG_TX_STATE_TRY_CNT_POS,
                                   le16_to_cpu(frame_status[i].sequence));
        }
}
#else
static void iwl_mvm_rx_tx_cmd_agg_dbg(struct iwl_mvm *mvm,
                                      struct iwl_rx_packet *pkt)
{}
#endif /* CONFIG_IWLWIFI_DEBUG */

static void iwl_mvm_rx_tx_cmd_agg(struct iwl_mvm *mvm,
                                  struct iwl_rx_packet *pkt)
{
        struct iwl_mvm_tx_resp *tx_resp = (void *)pkt->data;
        int sta_id = IWL_MVM_TX_RES_GET_RA(tx_resp->ra_tid);
        int tid = IWL_MVM_TX_RES_GET_TID(tx_resp->ra_tid);
        u16 sequence = le16_to_cpu(pkt->hdr.sequence);
        struct ieee80211_sta *sta;

        if (WARN_ON_ONCE(SEQ_TO_QUEUE(sequence) < mvm->first_agg_queue))
                return;

        if (WARN_ON_ONCE(tid == IWL_TID_NON_QOS))
                return;

        iwl_mvm_rx_tx_cmd_agg_dbg(mvm, pkt);

        rcu_read_lock();

        sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]);

        if (!WARN_ON_ONCE(IS_ERR_OR_NULL(sta))) {
                struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
                mvmsta->tid_data[tid].rate_n_flags =
                        le32_to_cpu(tx_resp->initial_rate);
                mvmsta->tid_data[tid].tx_time =
                        le16_to_cpu(tx_resp->wireless_media_time);
        }

        rcu_read_unlock();
}

void iwl_mvm_rx_tx_cmd(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb)
{
        struct iwl_rx_packet *pkt = rxb_addr(rxb);
        struct iwl_mvm_tx_resp *tx_resp = (void *)pkt->data;

        if (tx_resp->frame_count == 1)
                iwl_mvm_rx_tx_cmd_single(mvm, pkt);
        else
                iwl_mvm_rx_tx_cmd_agg(mvm, pkt);
}

static void iwl_mvm_tx_info_from_ba_notif(struct ieee80211_tx_info *info,
                                          struct iwl_mvm_ba_notif *ba_notif,
                                          struct iwl_mvm_tid_data *tid_data)
{
        info->flags |= IEEE80211_TX_STAT_AMPDU;
        info->status.ampdu_ack_len = ba_notif->txed_2_done;
        info->status.ampdu_len = ba_notif->txed;
        iwl_mvm_hwrate_to_tx_status(tid_data->rate_n_flags,
                                    info);
        /* TODO: not accounted if the whole A-MPDU failed */
        info->status.tx_time = tid_data->tx_time;
        info->status.status_driver_data[0] =
                (void *)(uintptr_t)ba_notif->reduced_txp;
        info->status.status_driver_data[1] =
                (void *)(uintptr_t)tid_data->rate_n_flags;
}

void iwl_mvm_rx_ba_notif(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb)
{
        struct iwl_rx_packet *pkt = rxb_addr(rxb);
        struct iwl_mvm_ba_notif *ba_notif = (void *)pkt->data;
        struct sk_buff_head reclaimed_skbs;
        struct iwl_mvm_tid_data *tid_data;
        struct ieee80211_sta *sta;
        struct iwl_mvm_sta *mvmsta;
        struct sk_buff *skb;
        int sta_id, tid, freed;
        /* "flow" corresponds to Tx queue */
        u16 scd_flow = le16_to_cpu(ba_notif->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_notif->scd_ssn);

        sta_id = ba_notif->sta_id;
        tid = ba_notif->tid;

        if (WARN_ONCE(sta_id >= IWL_MVM_STATION_COUNT ||
                      tid >= IWL_MAX_TID_COUNT,
                      "sta_id %d tid %d", sta_id, tid))
                return;

        rcu_read_lock();

        sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]);

        /* Reclaiming frames for a station that has been deleted ? */
        if (WARN_ON_ONCE(IS_ERR_OR_NULL(sta))) {
                rcu_read_unlock();
                return;
        }

        mvmsta = iwl_mvm_sta_from_mac80211(sta);
        tid_data = &mvmsta->tid_data[tid];

        if (tid_data->txq_id != scd_flow) {
                IWL_ERR(mvm,
                        "invalid BA notification: Q %d, tid %d, flow %d\n",
                        tid_data->txq_id, tid, scd_flow);
                rcu_read_unlock();
                return;
        }

        spin_lock_bh(&mvmsta->lock);

        __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(mvm->trans, scd_flow, ba_resp_scd_ssn,
                          &reclaimed_skbs);

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

        IWL_DEBUG_TX_REPLY(mvm, "reduced txp from ba notif %d\n",
                           ba_notif->reduced_txp);
        tid_data->next_reclaimed = ba_resp_scd_ssn;

        iwl_mvm_check_ratid_empty(mvm, sta, 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(mvm->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;

                /* this is the first skb we deliver in this batch */
                /* put the rate scaling data there */
                if (freed == 1)
                        iwl_mvm_tx_info_from_ba_notif(info, ba_notif, tid_data);
        }

        spin_unlock_bh(&mvmsta->lock);

        /* We got a BA notif with 0 acked or scd_ssn didn't progress which is
         * possible (i.e. first MPDU in the aggregation wasn't acked)
         * Still it's important to update RS about sent vs. acked.
         */
        if (skb_queue_empty(&reclaimed_skbs)) {
                struct ieee80211_tx_info ba_info = {};
                struct ieee80211_chanctx_conf *chanctx_conf = NULL;

                if (mvmsta->vif)
                        chanctx_conf =
                                rcu_dereference(mvmsta->vif->chanctx_conf);

                if (WARN_ON_ONCE(!chanctx_conf))
                        goto out;

                ba_info.band = chanctx_conf->def.chan->band;
                iwl_mvm_tx_info_from_ba_notif(&ba_info, ba_notif, tid_data);

                IWL_DEBUG_TX_REPLY(mvm, "No reclaim. Update rs directly\n");
                iwl_mvm_rs_tx_status(mvm, sta, tid, &ba_info);
        }

out:
        rcu_read_unlock();

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

/*
 * Note that there are transports that buffer frames before they reach
 * the firmware. This means that after flush_tx_path is called, the
 * queue might not be empty. The race-free way to handle this is to:
 * 1) set the station as draining
 * 2) flush the Tx path
 * 3) wait for the transport queues to be empty
 */
int iwl_mvm_flush_tx_path(struct iwl_mvm *mvm, u32 tfd_msk, u32 flags)
{
        int ret;
        struct iwl_tx_path_flush_cmd flush_cmd = {
                .queues_ctl = cpu_to_le32(tfd_msk),
                .flush_ctl = cpu_to_le16(DUMP_TX_FIFO_FLUSH),
        };

        ret = iwl_mvm_send_cmd_pdu(mvm, TXPATH_FLUSH, flags,
                                   sizeof(flush_cmd), &flush_cmd);
        if (ret)
                IWL_ERR(mvm, "Failed to send flush command (%d)\n", ret);
        return ret;
}