rtl871x_xmit.c

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/******************************************************************************
 * rtl871x_xmit.c
 *
 * Copyright(c) 2007 - 2010 Realtek Corporation. All rights reserved.
 * Linux device driver for RTL8192SU
 *
 * 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
 *
 * Modifications for inclusion into the Linux staging tree are
 * Copyright(c) 2010 Larry Finger. All rights reserved.
 *
 * Contact information:
 * WLAN FAE <[email protected]>
 * Larry Finger <[email protected]>
 *
 ******************************************************************************/

#define _RTL871X_XMIT_C_

#include "osdep_service.h"
#include "drv_types.h"
#include "wifi.h"
#include "osdep_intf.h"
#include "usb_ops.h"


static const u8 P802_1H_OUI[P80211_OUI_LEN] = {0x00, 0x00, 0xf8};
static const u8 RFC1042_OUI[P80211_OUI_LEN] = {0x00, 0x00, 0x00};
static void init_hwxmits(struct hw_xmit *phwxmit, sint entry);
static void alloc_hwxmits(struct _adapter *padapter);
static void free_hwxmits(struct _adapter *padapter);

static void _init_txservq(struct tx_servq *ptxservq)
{
    _init_listhead(&ptxservq->tx_pending);
    _init_queue(&ptxservq->sta_pending);
    ptxservq->qcnt = 0;
}

void _r8712_init_sta_xmit_priv(struct sta_xmit_priv *psta_xmitpriv)
{
    memset((unsigned char *)psta_xmitpriv, 0,
         sizeof(struct sta_xmit_priv));
    spin_lock_init(&psta_xmitpriv->lock);
    _init_txservq(&psta_xmitpriv->be_q);
    _init_txservq(&psta_xmitpriv->bk_q);
    _init_txservq(&psta_xmitpriv->vi_q);
    _init_txservq(&psta_xmitpriv->vo_q);
    _init_listhead(&psta_xmitpriv->legacy_dz);
    _init_listhead(&psta_xmitpriv->apsd);
}

sint _r8712_init_xmit_priv(struct xmit_priv *pxmitpriv,
               struct _adapter *padapter)
{
    sint i;
    struct xmit_buf *pxmitbuf;
    struct xmit_frame *pxframe;

    memset((unsigned char *)pxmitpriv, 0, sizeof(struct xmit_priv));
    spin_lock_init(&pxmitpriv->lock);
    /*
    Please insert all the queue initialization using _init_queue below
    */
    pxmitpriv->adapter = padapter;
    _init_queue(&pxmitpriv->be_pending);
    _init_queue(&pxmitpriv->bk_pending);
    _init_queue(&pxmitpriv->vi_pending);
    _init_queue(&pxmitpriv->vo_pending);
    _init_queue(&pxmitpriv->bm_pending);
    _init_queue(&pxmitpriv->legacy_dz_queue);
    _init_queue(&pxmitpriv->apsd_queue);
    _init_queue(&pxmitpriv->free_xmit_queue);
    /*
    Please allocate memory with the sz = (struct xmit_frame) * NR_XMITFRAME,
    and initialize free_xmit_frame below.
    Please also apply  free_txobj to link_up all the xmit_frames...
    */
    pxmitpriv->pallocated_frame_buf = _malloc(NR_XMITFRAME *
                      sizeof(struct xmit_frame) + 4);
    if (pxmitpriv->pallocated_frame_buf == NULL) {
        pxmitpriv->pxmit_frame_buf = NULL;
        return _FAIL;
    }
    pxmitpriv->pxmit_frame_buf = pxmitpriv->pallocated_frame_buf + 4 -
            ((addr_t) (pxmitpriv->pallocated_frame_buf) & 3);
    pxframe = (struct xmit_frame *) pxmitpriv->pxmit_frame_buf;
    for (i = 0; i < NR_XMITFRAME; i++) {
        _init_listhead(&(pxframe->list));
        pxframe->padapter = padapter;
        pxframe->frame_tag = DATA_FRAMETAG;
        pxframe->pkt = NULL;
        pxframe->buf_addr = NULL;
        pxframe->pxmitbuf = NULL;
        list_insert_tail(&(pxframe->list),
                 &(pxmitpriv->free_xmit_queue.queue));
        pxframe++;
    }
    pxmitpriv->free_xmitframe_cnt = NR_XMITFRAME;
    /*
        init xmit hw_txqueue
    */
    _r8712_init_hw_txqueue(&pxmitpriv->be_txqueue, BE_QUEUE_INX);
    _r8712_init_hw_txqueue(&pxmitpriv->bk_txqueue, BK_QUEUE_INX);
    _r8712_init_hw_txqueue(&pxmitpriv->vi_txqueue, VI_QUEUE_INX);
    _r8712_init_hw_txqueue(&pxmitpriv->vo_txqueue, VO_QUEUE_INX);
    _r8712_init_hw_txqueue(&pxmitpriv->bmc_txqueue, BMC_QUEUE_INX);
    pxmitpriv->frag_len = MAX_FRAG_THRESHOLD;
    pxmitpriv->txirp_cnt = 1;
    /*per AC pending irp*/
    pxmitpriv->beq_cnt = 0;
    pxmitpriv->bkq_cnt = 0;
    pxmitpriv->viq_cnt = 0;
    pxmitpriv->voq_cnt = 0;
    /*init xmit_buf*/
    _init_queue(&pxmitpriv->free_xmitbuf_queue);
    _init_queue(&pxmitpriv->pending_xmitbuf_queue);
    pxmitpriv->pallocated_xmitbuf = _malloc(NR_XMITBUFF *
                    sizeof(struct xmit_buf) + 4);
    if (pxmitpriv->pallocated_xmitbuf  == NULL)
        return _FAIL;
    pxmitpriv->pxmitbuf = pxmitpriv->pallocated_xmitbuf + 4 -
                  ((addr_t)(pxmitpriv->pallocated_xmitbuf) & 3);
    pxmitbuf = (struct xmit_buf *)pxmitpriv->pxmitbuf;
    for (i = 0; i < NR_XMITBUFF; i++) {
        _init_listhead(&pxmitbuf->list);
        pxmitbuf->pallocated_buf = _malloc(MAX_XMITBUF_SZ +
                       XMITBUF_ALIGN_SZ);
        if (pxmitbuf->pallocated_buf == NULL)
            return _FAIL;
        pxmitbuf->pbuf = pxmitbuf->pallocated_buf + XMITBUF_ALIGN_SZ -
                 ((addr_t) (pxmitbuf->pallocated_buf) &
                 (XMITBUF_ALIGN_SZ - 1));
        r8712_xmit_resource_alloc(padapter, pxmitbuf);
        list_insert_tail(&pxmitbuf->list,
                 &(pxmitpriv->free_xmitbuf_queue.queue));
        pxmitbuf++;
    }
    pxmitpriv->free_xmitbuf_cnt = NR_XMITBUFF;
    _init_workitem(&padapter->wkFilterRxFF0, r8712_SetFilter, padapter);
    alloc_hwxmits(padapter);
    init_hwxmits(pxmitpriv->hwxmits, pxmitpriv->hwxmit_entry);
    tasklet_init(&pxmitpriv->xmit_tasklet,
        (void(*)(unsigned long))r8712_xmit_bh,
        (unsigned long)padapter);
    return _SUCCESS;
}

void _free_xmit_priv(struct xmit_priv *pxmitpriv)
{
    int i;
    struct _adapter *padapter = pxmitpriv->adapter;
    struct xmit_frame *pxmitframe = (struct xmit_frame *)
                    pxmitpriv->pxmit_frame_buf;
    struct xmit_buf *pxmitbuf = (struct xmit_buf *)pxmitpriv->pxmitbuf;

    if (pxmitpriv->pxmit_frame_buf == NULL)
        return;
    for (i = 0; i < NR_XMITFRAME; i++) {
        r8712_xmit_complete(padapter, pxmitframe);
        pxmitframe++;
    }
    for (i = 0; i < NR_XMITBUFF; i++) {
        r8712_xmit_resource_free(padapter, pxmitbuf);
        kfree(pxmitbuf->pallocated_buf);
        pxmitbuf++;
    }
    kfree(pxmitpriv->pallocated_frame_buf);
    kfree(pxmitpriv->pallocated_xmitbuf);
    free_hwxmits(padapter);
}

sint r8712_update_attrib(struct _adapter *padapter, _pkt *pkt,
           struct pkt_attrib *pattrib)
{
    uint i;
    struct pkt_file pktfile;
    struct sta_info *psta = NULL;
    struct ethhdr etherhdr;

    struct tx_cmd txdesc;

    sint bmcast;
    struct sta_priv     *pstapriv = &padapter->stapriv;
    struct security_priv    *psecuritypriv = &padapter->securitypriv;
    struct mlme_priv    *pmlmepriv = &padapter->mlmepriv;
    struct qos_priv     *pqospriv = &pmlmepriv->qospriv;

    _r8712_open_pktfile(pkt, &pktfile);

    i = _r8712_pktfile_read(&pktfile, (unsigned char *)&etherhdr, ETH_HLEN);

    pattrib->ether_type = ntohs(etherhdr.h_proto);

{
    u8 bool;
    /*If driver xmit ARP packet, driver can set ps mode to initial
     * setting. It stands for getting DHCP or fix IP.*/
    if (pattrib->ether_type == 0x0806) {
        if (padapter->pwrctrlpriv.pwr_mode !=
            padapter->registrypriv.power_mgnt) {
            _cancel_timer(&(pmlmepriv->dhcp_timer), &bool);
            r8712_set_ps_mode(padapter, padapter->registrypriv.
                power_mgnt, padapter->registrypriv.smart_ps);
        }
    }
}
    memcpy(pattrib->dst, &etherhdr.h_dest, ETH_ALEN);
    memcpy(pattrib->src, &etherhdr.h_source, ETH_ALEN);
    pattrib->pctrl = 0;
    if ((check_fwstate(pmlmepriv, WIFI_ADHOC_STATE) == true) ||
        (check_fwstate(pmlmepriv, WIFI_ADHOC_MASTER_STATE) == true)) {
        memcpy(pattrib->ra, pattrib->dst, ETH_ALEN);
        memcpy(pattrib->ta, pattrib->src, ETH_ALEN);
    } else if (check_fwstate(pmlmepriv, WIFI_STATION_STATE)) {
        memcpy(pattrib->ra, get_bssid(pmlmepriv), ETH_ALEN);
        memcpy(pattrib->ta, pattrib->src, ETH_ALEN);
    } else if (check_fwstate(pmlmepriv, WIFI_AP_STATE)) {
        memcpy(pattrib->ra, pattrib->dst, ETH_ALEN);
        memcpy(pattrib->ta, get_bssid(pmlmepriv), ETH_ALEN);
    } else if (check_fwstate(pmlmepriv, WIFI_MP_STATE) == true) {
        /*firstly, filter packet not belongs to mp*/
        if (pattrib->ether_type != 0x8712)
            return _FAIL;
        /* for mp storing the txcmd per packet,
         * according to the info of txcmd to update pattrib */
        /*get MP_TXDESC_SIZE bytes txcmd per packet*/
        i = _r8712_pktfile_read(&pktfile, (u8 *)&txdesc, TXDESC_SIZE);
        memcpy(pattrib->ra, pattrib->dst, ETH_ALEN);
        memcpy(pattrib->ta, pattrib->src, ETH_ALEN);
        pattrib->pctrl = 1;
    }
    /* r8712_xmitframe_coalesce() overwrite this!*/
    pattrib->pktlen = pktfile.pkt_len;
    if (ETH_P_IP == pattrib->ether_type) {
        /* The following is for DHCP and ARP packet, we use cck1M to
         * tx these packets and let LPS awake some time
         * to prevent DHCP protocol fail */
        u8 tmp[24];
        _r8712_pktfile_read(&pktfile, &tmp[0], 24);
        pattrib->dhcp_pkt = 0;
        if (pktfile.pkt_len > 282) {/*MINIMUM_DHCP_PACKET_SIZE)*/
            if (ETH_P_IP == pattrib->ether_type) {/* IP header*/
                if (((tmp[21] == 68) && (tmp[23] == 67)) ||
                    ((tmp[21] == 67) && (tmp[23] == 68))) {
                    /* 68 : UDP BOOTP client
                     * 67 : UDP BOOTP server
                     * Use low rate to send DHCP packet.*/
                    pattrib->dhcp_pkt = 1;
                }
            }
        }
    }
    bmcast = IS_MCAST(pattrib->ra);
    /* get sta_info*/
    if (bmcast) {
        psta = r8712_get_bcmc_stainfo(padapter);
        pattrib->mac_id = 4;
    } else {
        if (check_fwstate(pmlmepriv, WIFI_MP_STATE) == true) {
            psta = r8712_get_stainfo(pstapriv,
                         get_bssid(pmlmepriv));
            pattrib->mac_id = 5;
        } else {
            psta = r8712_get_stainfo(pstapriv, pattrib->ra);
            if (psta == NULL)  /* drop the pkt */
                return _FAIL;
            if (check_fwstate(pmlmepriv, WIFI_STATION_STATE))
                pattrib->mac_id = 5;
            else
                pattrib->mac_id = psta->mac_id;
        }
    }

    if (psta) {
        pattrib->psta = psta;
    } else {
        /* if we cannot get psta => drrp the pkt */
        return _FAIL;
    }

    pattrib->ack_policy = 0;
    /* get ether_hdr_len */
    pattrib->pkt_hdrlen = ETH_HLEN;

    if (pqospriv->qos_option)
        r8712_set_qos(&pktfile, pattrib);
    else {
        pattrib->hdrlen = WLAN_HDR_A3_LEN;
        pattrib->subtype = WIFI_DATA_TYPE;
        pattrib->priority = 0;
    }
    if (psta->ieee8021x_blocked == true) {
        pattrib->encrypt = 0;
        if ((pattrib->ether_type != 0x888e) &&
            (check_fwstate(pmlmepriv, WIFI_MP_STATE) == false))
            return _FAIL;
    } else
        GET_ENCRY_ALGO(psecuritypriv, psta, pattrib->encrypt, bmcast);
    switch (pattrib->encrypt) {
    case _WEP40_:
    case _WEP104_:
        pattrib->iv_len = 4;
        pattrib->icv_len = 4;
        break;
    case _TKIP_:
        pattrib->iv_len = 8;
        pattrib->icv_len = 4;
        if (padapter->securitypriv.busetkipkey == _FAIL)
            return _FAIL;
        break;
    case _AES_:
        pattrib->iv_len = 8;
        pattrib->icv_len = 8;
        break;
    default:
        pattrib->iv_len = 0;
        pattrib->icv_len = 0;
        break;
    }

    if (pattrib->encrypt &&
        ((padapter->securitypriv.sw_encrypt == true) ||
         (psecuritypriv->hw_decrypted == false)))
        pattrib->bswenc = true;
    else
        pattrib->bswenc = false;
    /* if in MP_STATE, update pkt_attrib from mp_txcmd, and overwrite
     * some settings above.*/
    if (check_fwstate(pmlmepriv, WIFI_MP_STATE) == true)
        pattrib->priority = (txdesc.txdw1 >> QSEL_SHT) & 0x1f;
    return _SUCCESS;
}

static sint xmitframe_addmic(struct _adapter *padapter,
                 struct xmit_frame *pxmitframe)
{
    u32 curfragnum, length, datalen;
    u8  *pframe, *payload, mic[8];
    struct  mic_data micdata;
    struct  sta_info *stainfo;
    struct  qos_priv *pqospriv = &(padapter->mlmepriv.qospriv);
    struct  pkt_attrib  *pattrib = &pxmitframe->attrib;
    struct  security_priv *psecuritypriv = &padapter->securitypriv;
    struct  xmit_priv *pxmitpriv = &padapter->xmitpriv;
    u8 priority[4] = {0x0, 0x0, 0x0, 0x0};
    sint bmcst = IS_MCAST(pattrib->ra);

    if (pattrib->psta)
        stainfo = pattrib->psta;
    else
        stainfo = r8712_get_stainfo(&padapter->stapriv,
                        &pattrib->ra[0]);
    if (pattrib->encrypt == _TKIP_) {
        /*encode mic code*/
        if (stainfo != NULL) {
            u8 null_key[16] = {0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
                       0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
                       0x0, 0x0};
            datalen = pattrib->pktlen - pattrib->hdrlen;
            pframe = pxmitframe->buf_addr + TXDESC_OFFSET;
            if (bmcst) {
                if (!memcmp(psecuritypriv->XGrptxmickey
                   [psecuritypriv->XGrpKeyid].skey,
                   null_key, 16))
                    return _FAIL;
                /*start to calculate the mic code*/
                r8712_secmicsetkey(&micdata,
                     psecuritypriv->
                     XGrptxmickey[psecuritypriv->
                    XGrpKeyid].skey);
            } else {
                if (!memcmp(&stainfo->tkiptxmickey.skey[0],
                        null_key, 16))
                    return _FAIL;
                /* start to calculate the mic code */
                r8712_secmicsetkey(&micdata,
                         &stainfo->tkiptxmickey.skey[0]);
            }
            if (pframe[1] & 1) {   /* ToDS==1 */
                r8712_secmicappend(&micdata,
                           &pframe[16], 6); /*DA*/
                if (pframe[1]&2)  /* From Ds==1 */
                    r8712_secmicappend(&micdata,
                               &pframe[24], 6);
                else
                    r8712_secmicappend(&micdata,
                               &pframe[10], 6);
            } else {    /* ToDS==0 */
                r8712_secmicappend(&micdata,
                           &pframe[4], 6); /* DA */
                if (pframe[1]&2)  /* From Ds==1 */
                    r8712_secmicappend(&micdata,
                               &pframe[16], 6);
                else
                    r8712_secmicappend(&micdata,
                               &pframe[10], 6);
            }
            if (pqospriv->qos_option == 1)
                    priority[0] = (u8)pxmitframe->
                              attrib.priority;
            r8712_secmicappend(&micdata, &priority[0], 4);
            payload = pframe;
            for (curfragnum = 0; curfragnum < pattrib->nr_frags;
                 curfragnum++) {
                payload = (u8 *)RND4((addr_t)(payload));
                payload = payload+pattrib->
                      hdrlen+pattrib->iv_len;
                if ((curfragnum + 1) == pattrib->nr_frags) {
                    length = pattrib->last_txcmdsz -
                          pattrib->hdrlen -
                          pattrib->iv_len -
                          ((psecuritypriv->sw_encrypt)
                          ? pattrib->icv_len : 0);
                    r8712_secmicappend(&micdata, payload,
                               length);
                    payload = payload+length;
                } else{
                    length = pxmitpriv->frag_len -
                        pattrib->hdrlen-pattrib->iv_len -
                        ((psecuritypriv->sw_encrypt) ?
                        pattrib->icv_len : 0);
                    r8712_secmicappend(&micdata, payload,
                               length);
                    payload = payload + length +
                          pattrib->icv_len;
                }
            }
            r8712_secgetmic(&micdata, &(mic[0]));
            /* add mic code  and add the mic code length in
             * last_txcmdsz */
            memcpy(payload, &(mic[0]), 8);
            pattrib->last_txcmdsz += 8;
            payload = payload-pattrib->last_txcmdsz + 8;
        }
    }
    return _SUCCESS;
}

static sint xmitframe_swencrypt(struct _adapter *padapter,
                struct xmit_frame *pxmitframe)
{
    struct pkt_attrib   *pattrib = &pxmitframe->attrib;

    if (pattrib->bswenc) {
        switch (pattrib->encrypt) {
        case _WEP40_:
        case _WEP104_:
            r8712_wep_encrypt(padapter, (u8 *)pxmitframe);
            break;
        case _TKIP_:
            r8712_tkip_encrypt(padapter, (u8 *)pxmitframe);
            break;
        case _AES_:
            r8712_aes_encrypt(padapter, (u8 *)pxmitframe);
            break;
        default:
                break;
        }
    }
    return _SUCCESS;
}

static sint make_wlanhdr(struct _adapter *padapter , u8 *hdr,
             struct pkt_attrib *pattrib)
{
    u16 *qc;

    struct ieee80211_hdr *pwlanhdr = (struct ieee80211_hdr *)hdr;
    struct mlme_priv *pmlmepriv = &padapter->mlmepriv;
    struct qos_priv *pqospriv = &pmlmepriv->qospriv;
    u16 *fctrl = &pwlanhdr->frame_ctl;
    memset(hdr, 0, WLANHDR_OFFSET);
    SetFrameSubType(fctrl, pattrib->subtype);
    if (pattrib->subtype & WIFI_DATA_TYPE) {
        if ((check_fwstate(pmlmepriv,  WIFI_STATION_STATE) == true)) {
            /* to_ds = 1, fr_ds = 0; */
            SetToDs(fctrl);
            memcpy(pwlanhdr->addr1, get_bssid(pmlmepriv),
                ETH_ALEN);
            memcpy(pwlanhdr->addr2, pattrib->src, ETH_ALEN);
            memcpy(pwlanhdr->addr3, pattrib->dst, ETH_ALEN);
        } else if ((check_fwstate(pmlmepriv, WIFI_AP_STATE) == true)) {
            /* to_ds = 0, fr_ds = 1; */
            SetFrDs(fctrl);
            memcpy(pwlanhdr->addr1, pattrib->dst, ETH_ALEN);
            memcpy(pwlanhdr->addr2, get_bssid(pmlmepriv),
                ETH_ALEN);
            memcpy(pwlanhdr->addr3, pattrib->src, ETH_ALEN);
        } else if ((check_fwstate(pmlmepriv, WIFI_ADHOC_STATE) == true)
               || (check_fwstate(pmlmepriv, WIFI_ADHOC_MASTER_STATE)
               == true)) {
            memcpy(pwlanhdr->addr1, pattrib->dst, ETH_ALEN);
            memcpy(pwlanhdr->addr2, pattrib->src, ETH_ALEN);
            memcpy(pwlanhdr->addr3, get_bssid(pmlmepriv),
                ETH_ALEN);
        } else if (check_fwstate(pmlmepriv, WIFI_MP_STATE) == true) {
            memcpy(pwlanhdr->addr1, pattrib->dst, ETH_ALEN);
            memcpy(pwlanhdr->addr2, pattrib->src, ETH_ALEN);
            memcpy(pwlanhdr->addr3, get_bssid(pmlmepriv),
                ETH_ALEN);
        } else
            return _FAIL;

        if (pattrib->encrypt)
            SetPrivacy(fctrl);
        if (pqospriv->qos_option) {
            qc = (unsigned short *)(hdr + pattrib->hdrlen - 2);
            if (pattrib->priority)
                SetPriority(qc, pattrib->priority);
            SetAckpolicy(qc, pattrib->ack_policy);
        }
        /* TODO: fill HT Control Field */
        /* Update Seq Num will be handled by f/w */
        {
            struct sta_info *psta;

            sint bmcst = IS_MCAST(pattrib->ra);
            if (pattrib->psta)
                psta = pattrib->psta;
            else {
                if (bmcst)
                    psta = r8712_get_bcmc_stainfo(padapter);
                else
                    psta =
                     r8712_get_stainfo(&padapter->stapriv,
                     pattrib->ra);
            }
            if (psta) {
                psta->sta_xmitpriv.txseq_tid
                          [pattrib->priority]++;
                psta->sta_xmitpriv.txseq_tid[pattrib->priority]
                           &= 0xFFF;
                pattrib->seqnum = psta->sta_xmitpriv.
                          txseq_tid[pattrib->priority];
                SetSeqNum(hdr, pattrib->seqnum);
            }
        }
    }
    return _SUCCESS;
}

static sint r8712_put_snap(u8 *data, u16 h_proto)
{
    struct ieee80211_snap_hdr *snap;
    const u8 *oui;

    snap = (struct ieee80211_snap_hdr *)data;
    snap->dsap = 0xaa;
    snap->ssap = 0xaa;
    snap->ctrl = 0x03;
    if (h_proto == 0x8137 || h_proto == 0x80f3)
        oui = P802_1H_OUI;
    else
        oui = RFC1042_OUI;
    snap->oui[0] = oui[0];
    snap->oui[1] = oui[1];
    snap->oui[2] = oui[2];
    *(u16 *)(data + SNAP_SIZE) = htons(h_proto);
    return SNAP_SIZE + sizeof(u16);
}

/*
 * This sub-routine will perform all the following:
 * 1. remove 802.3 header.
 * 2. create wlan_header, based on the info in pxmitframe
 * 3. append sta's iv/ext-iv
 * 4. append LLC
 * 5. move frag chunk from pframe to pxmitframe->mem
 * 6. apply sw-encrypt, if necessary.
 */
sint r8712_xmitframe_coalesce(struct _adapter *padapter, _pkt *pkt,
            struct xmit_frame *pxmitframe)
{
    struct pkt_file pktfile;

    sint    frg_len, mpdu_len, llc_sz;
    u32 mem_sz;
    u8  frg_inx;
    addr_t addr;
    u8 *pframe, *mem_start, *ptxdesc;
    struct sta_info     *psta;
    struct security_priv    *psecuritypriv = &padapter->securitypriv;
    struct mlme_priv    *pmlmepriv = &padapter->mlmepriv;
    struct xmit_priv    *pxmitpriv = &padapter->xmitpriv;
    struct pkt_attrib   *pattrib = &pxmitframe->attrib;
    u8 *pbuf_start;
    sint bmcst = IS_MCAST(pattrib->ra);

    if (pattrib->psta == NULL)
        return _FAIL;
    psta = pattrib->psta;
    if (pxmitframe->buf_addr == NULL)
        return _FAIL;
    pbuf_start = pxmitframe->buf_addr;
    ptxdesc = pbuf_start;
    mem_start = pbuf_start + TXDESC_OFFSET;
    if (make_wlanhdr(padapter, mem_start, pattrib) == _FAIL)
        return _FAIL;
    _r8712_open_pktfile(pkt, &pktfile);
    _r8712_pktfile_read(&pktfile, NULL, (uint) pattrib->pkt_hdrlen);
    if (check_fwstate(pmlmepriv, WIFI_MP_STATE) == true) {
        /* truncate TXDESC_SIZE bytes txcmd if at mp mode for 871x */
        if (pattrib->ether_type == 0x8712) {
            /* take care -  update_txdesc overwrite this */
            _r8712_pktfile_read(&pktfile, ptxdesc, TXDESC_SIZE);
        }
    }
    pattrib->pktlen = pktfile.pkt_len;
    frg_inx = 0;
    frg_len = pxmitpriv->frag_len - 4;
    while (1) {
        llc_sz = 0;
        mpdu_len = frg_len;
        pframe = mem_start;
        SetMFrag(mem_start);
        pframe += pattrib->hdrlen;
        mpdu_len -= pattrib->hdrlen;
        /* adding icv, if necessary...*/
        if (pattrib->iv_len) {
            if (psta != NULL) {
                switch (pattrib->encrypt) {
                case _WEP40_:
                case _WEP104_:
                    WEP_IV(pattrib->iv, psta->txpn,
                           (u8)psecuritypriv->
                           PrivacyKeyIndex);
                    break;
                case _TKIP_:
                    if (bmcst)
                        TKIP_IV(pattrib->iv,
                            psta->txpn,
                            (u8)psecuritypriv->
                            XGrpKeyid);
                    else
                        TKIP_IV(pattrib->iv, psta->txpn,
                            0);
                    break;
                case _AES_:
                    if (bmcst)
                        AES_IV(pattrib->iv, psta->txpn,
                            (u8)psecuritypriv->
                            XGrpKeyid);
                    else
                        AES_IV(pattrib->iv, psta->txpn,
                               0);
                    break;
                }
            }
            memcpy(pframe, pattrib->iv, pattrib->iv_len);
            pframe += pattrib->iv_len;
            mpdu_len -= pattrib->iv_len;
        }
        if (frg_inx == 0) {
            llc_sz = r8712_put_snap(pframe, pattrib->ether_type);
            pframe += llc_sz;
            mpdu_len -= llc_sz;
        }
        if ((pattrib->icv_len > 0) && (pattrib->bswenc))
            mpdu_len -= pattrib->icv_len;
        if (bmcst)
            mem_sz = _r8712_pktfile_read(&pktfile, pframe,
                 pattrib->pktlen);
        else
            mem_sz = _r8712_pktfile_read(&pktfile, pframe,
                 mpdu_len);
        pframe += mem_sz;
        if ((pattrib->icv_len > 0) && (pattrib->bswenc)) {
            memcpy(pframe, pattrib->icv, pattrib->icv_len);
            pframe += pattrib->icv_len;
        }
        frg_inx++;
        if (bmcst || (r8712_endofpktfile(&pktfile) == true)) {
            pattrib->nr_frags = frg_inx;
            pattrib->last_txcmdsz = pattrib->hdrlen +
                        pattrib->iv_len +
                        ((pattrib->nr_frags == 1) ?
                        llc_sz : 0) +
                        ((pattrib->bswenc) ?
                        pattrib->icv_len : 0) + mem_sz;
            ClearMFrag(mem_start);
            break;
        }
        addr = (addr_t)(pframe);
        mem_start = (unsigned char *)RND4(addr) + TXDESC_OFFSET;
        memcpy(mem_start, pbuf_start + TXDESC_OFFSET, pattrib->hdrlen);
    }

    if (xmitframe_addmic(padapter, pxmitframe) == _FAIL)
        return _FAIL;
    xmitframe_swencrypt(padapter, pxmitframe);
    return _SUCCESS;
}

void r8712_update_protection(struct _adapter *padapter, u8 *ie, uint ie_len)
{
    uint    protection;
    u8  *perp;
    sint     erp_len;
    struct  xmit_priv *pxmitpriv = &padapter->xmitpriv;
    struct  registry_priv *pregistrypriv = &padapter->registrypriv;

    switch (pxmitpriv->vcs_setting) {
    case DISABLE_VCS:
        pxmitpriv->vcs = NONE_VCS;
        break;
    case ENABLE_VCS:
        break;
    case AUTO_VCS:
    default:
        perp = r8712_get_ie(ie, _ERPINFO_IE_, &erp_len, ie_len);
        if (perp == NULL)
            pxmitpriv->vcs = NONE_VCS;
        else {
            protection = (*(perp + 2)) & BIT(1);
            if (protection) {
                if (pregistrypriv->vcs_type == RTS_CTS)
                    pxmitpriv->vcs = RTS_CTS;
                else
                    pxmitpriv->vcs = CTS_TO_SELF;
            } else
                pxmitpriv->vcs = NONE_VCS;
        }
        break;
    }
}

struct xmit_buf *r8712_alloc_xmitbuf(struct xmit_priv *pxmitpriv)
{
    unsigned long irqL;
    struct xmit_buf *pxmitbuf =  NULL;
    struct list_head *plist, *phead;
    struct  __queue *pfree_xmitbuf_queue = &pxmitpriv->free_xmitbuf_queue;

    spin_lock_irqsave(&pfree_xmitbuf_queue->lock, irqL);
    if (_queue_empty(pfree_xmitbuf_queue) == true)
        pxmitbuf = NULL;
    else {
        phead = get_list_head(pfree_xmitbuf_queue);
        plist = get_next(phead);
        pxmitbuf = LIST_CONTAINOR(plist, struct xmit_buf, list);
        list_delete(&(pxmitbuf->list));
    }
    if (pxmitbuf !=  NULL)
        pxmitpriv->free_xmitbuf_cnt--;
    spin_unlock_irqrestore(&pfree_xmitbuf_queue->lock, irqL);
    return pxmitbuf;
}

int r8712_free_xmitbuf(struct xmit_priv *pxmitpriv, struct xmit_buf *pxmitbuf)
{
    unsigned long irqL;
    struct  __queue *pfree_xmitbuf_queue = &pxmitpriv->free_xmitbuf_queue;

    if (pxmitbuf == NULL)
        return _FAIL;
    spin_lock_irqsave(&pfree_xmitbuf_queue->lock, irqL);
    list_delete(&pxmitbuf->list);
    list_insert_tail(&(pxmitbuf->list), get_list_head(pfree_xmitbuf_queue));
    pxmitpriv->free_xmitbuf_cnt++;
    spin_unlock_irqrestore(&pfree_xmitbuf_queue->lock, irqL);
    return _SUCCESS;
}

/*
Calling context:
1. OS_TXENTRY
2. RXENTRY (rx_thread or RX_ISR/RX_CallBack)

If we turn on USE_RXTHREAD, then, no need for critical section.
Otherwise, we must use _enter/_exit critical to protect free_xmit_queue...

Must be very very cautious...

*/

struct xmit_frame *r8712_alloc_xmitframe(struct xmit_priv *pxmitpriv)
{
    /*
        Please remember to use all the osdep_service api,
        and lock/unlock or _enter/_exit critical to protect
        pfree_xmit_queue
    */
    unsigned long irqL;
    struct xmit_frame *pxframe = NULL;
    struct list_head *plist, *phead;
    struct  __queue *pfree_xmit_queue = &pxmitpriv->free_xmit_queue;

    spin_lock_irqsave(&pfree_xmit_queue->lock, irqL);
    if (_queue_empty(pfree_xmit_queue) == true)
        pxframe =  NULL;
    else {
        phead = get_list_head(pfree_xmit_queue);
        plist = get_next(phead);
        pxframe = LIST_CONTAINOR(plist, struct xmit_frame, list);
        list_delete(&(pxframe->list));
    }
    if (pxframe !=  NULL) {
        pxmitpriv->free_xmitframe_cnt--;
        pxframe->buf_addr = NULL;
        pxframe->pxmitbuf = NULL;
        pxframe->attrib.psta = NULL;
        pxframe->pkt = NULL;
    }
    spin_unlock_irqrestore(&pfree_xmit_queue->lock, irqL);
    return pxframe;
}

void r8712_free_xmitframe(struct xmit_priv *pxmitpriv,
              struct xmit_frame *pxmitframe)
{
    unsigned long irqL;
    struct  __queue *pfree_xmit_queue = &pxmitpriv->free_xmit_queue;
    struct _adapter *padapter = pxmitpriv->adapter;
    struct sk_buff *pndis_pkt = NULL;

    if (pxmitframe == NULL)
        return;
    spin_lock_irqsave(&pfree_xmit_queue->lock, irqL);
    list_delete(&pxmitframe->list);
    if (pxmitframe->pkt) {
        pndis_pkt = pxmitframe->pkt;
        pxmitframe->pkt = NULL;
    }
    list_insert_tail(&pxmitframe->list, get_list_head(pfree_xmit_queue));
    pxmitpriv->free_xmitframe_cnt++;
    spin_unlock_irqrestore(&pfree_xmit_queue->lock, irqL);
    if (netif_queue_stopped(padapter->pnetdev))
        netif_wake_queue(padapter->pnetdev);
}

void r8712_free_xmitframe_ex(struct xmit_priv *pxmitpriv,
              struct xmit_frame *pxmitframe)
{
    if (pxmitframe == NULL)
        return;
    if (pxmitframe->frame_tag == DATA_FRAMETAG)
        r8712_free_xmitframe(pxmitpriv, pxmitframe);
}

void r8712_free_xmitframe_queue(struct xmit_priv *pxmitpriv,
                struct  __queue *pframequeue)
{
    unsigned long irqL;
    struct list_head *plist, *phead;
    struct  xmit_frame  *pxmitframe;

    spin_lock_irqsave(&(pframequeue->lock), irqL);
    phead = get_list_head(pframequeue);
    plist = get_next(phead);
    while (end_of_queue_search(phead, plist) == false) {
        pxmitframe = LIST_CONTAINOR(plist, struct xmit_frame, list);
        plist = get_next(plist);
        r8712_free_xmitframe(pxmitpriv, pxmitframe);
    }
    spin_unlock_irqrestore(&(pframequeue->lock), irqL);
}

static inline struct tx_servq *get_sta_pending(struct _adapter *padapter,
                           struct  __queue **ppstapending,
                           struct sta_info *psta, sint up)
{

    struct tx_servq *ptxservq;
    struct hw_xmit *phwxmits =  padapter->xmitpriv.hwxmits;

    switch (up) {
    case 1:
    case 2:
        ptxservq = &(psta->sta_xmitpriv.bk_q);
        *ppstapending = &padapter->xmitpriv.bk_pending;
        (phwxmits+3)->accnt++;
        break;
    case 4:
    case 5:
        ptxservq = &(psta->sta_xmitpriv.vi_q);
        *ppstapending = &padapter->xmitpriv.vi_pending;
        (phwxmits+1)->accnt++;
        break;
    case 6:
    case 7:
        ptxservq = &(psta->sta_xmitpriv.vo_q);
        *ppstapending = &padapter->xmitpriv.vo_pending;
        (phwxmits+0)->accnt++;
        break;
    case 0:
    case 3:
    default:
        ptxservq = &(psta->sta_xmitpriv.be_q);
        *ppstapending = &padapter->xmitpriv.be_pending;
        (phwxmits + 2)->accnt++;
        break;
    }
    return ptxservq;
}

/*
 * Will enqueue pxmitframe to the proper queue, and indicate it
 * to xx_pending list.....
 */
sint r8712_xmit_classifier(struct _adapter *padapter,
               struct xmit_frame *pxmitframe)
{
    unsigned long irqL0;
    struct  __queue *pstapending;
    struct sta_info *psta;
    struct tx_servq *ptxservq;
    struct pkt_attrib *pattrib = &pxmitframe->attrib;
    struct sta_priv *pstapriv = &padapter->stapriv;
    struct mlme_priv *pmlmepriv = &padapter->mlmepriv;
    sint bmcst = IS_MCAST(pattrib->ra);

    if (pattrib->psta)
        psta = pattrib->psta;
    else {
        if (bmcst)
            psta = r8712_get_bcmc_stainfo(padapter);
        else {
            if (check_fwstate(pmlmepriv, WIFI_MP_STATE) == true)
                psta = r8712_get_stainfo(pstapriv,
                       get_bssid(pmlmepriv));
            else
                psta = r8712_get_stainfo(pstapriv, pattrib->ra);
        }
    }
    if (psta == NULL)
        return _FAIL;
    ptxservq = get_sta_pending(padapter, &pstapending,
           psta, pattrib->priority);
    spin_lock_irqsave(&pstapending->lock, irqL0);
    if (is_list_empty(&ptxservq->tx_pending))
        list_insert_tail(&ptxservq->tx_pending,
                 get_list_head(pstapending));
    list_insert_tail(&pxmitframe->list,
             get_list_head(&ptxservq->sta_pending));
    ptxservq->qcnt++;
    spin_unlock_irqrestore(&pstapending->lock, irqL0);
    return _SUCCESS;
}

static void alloc_hwxmits(struct _adapter *padapter)
{
    struct hw_xmit *hwxmits;
    struct xmit_priv *pxmitpriv = &padapter->xmitpriv;

    pxmitpriv->hwxmit_entry = HWXMIT_ENTRY;
    pxmitpriv->hwxmits = (struct hw_xmit *)_malloc(sizeof(struct hw_xmit) *
                 pxmitpriv->hwxmit_entry);
    if (pxmitpriv->hwxmits == NULL)
        return;
    hwxmits = pxmitpriv->hwxmits;
    if (pxmitpriv->hwxmit_entry == 5) {
        pxmitpriv->bmc_txqueue.head = 0;
        hwxmits[0] .phwtxqueue = &pxmitpriv->bmc_txqueue;
        hwxmits[0] .sta_queue = &pxmitpriv->bm_pending;
        pxmitpriv->vo_txqueue.head = 0;
        hwxmits[1] .phwtxqueue = &pxmitpriv->vo_txqueue;
        hwxmits[1] .sta_queue = &pxmitpriv->vo_pending;
    pxmitpriv->vi_txqueue.head = 0;
        hwxmits[2] .phwtxqueue = &pxmitpriv->vi_txqueue;
        hwxmits[2] .sta_queue = &pxmitpriv->vi_pending;
        pxmitpriv->bk_txqueue.head = 0;
        hwxmits[3] .phwtxqueue = &pxmitpriv->bk_txqueue;
        hwxmits[3] .sta_queue = &pxmitpriv->bk_pending;
        pxmitpriv->be_txqueue.head = 0;
        hwxmits[4] .phwtxqueue = &pxmitpriv->be_txqueue;
        hwxmits[4] .sta_queue = &pxmitpriv->be_pending;
    } else if (pxmitpriv->hwxmit_entry == 4) {
        pxmitpriv->vo_txqueue.head = 0;
        hwxmits[0] .phwtxqueue = &pxmitpriv->vo_txqueue;
        hwxmits[0] .sta_queue = &pxmitpriv->vo_pending;
        pxmitpriv->vi_txqueue.head = 0;
        hwxmits[1] .phwtxqueue = &pxmitpriv->vi_txqueue;
        hwxmits[1] .sta_queue = &pxmitpriv->vi_pending;
        pxmitpriv->be_txqueue.head = 0;
        hwxmits[2] .phwtxqueue = &pxmitpriv->be_txqueue;
        hwxmits[2] .sta_queue = &pxmitpriv->be_pending;
        pxmitpriv->bk_txqueue.head = 0;
        hwxmits[3] .phwtxqueue = &pxmitpriv->bk_txqueue;
        hwxmits[3] .sta_queue = &pxmitpriv->bk_pending;
    }
}

static void free_hwxmits(struct _adapter *padapter)
{
    struct xmit_priv *pxmitpriv = &padapter->xmitpriv;

    kfree(pxmitpriv->hwxmits);
}

static void init_hwxmits(struct hw_xmit *phwxmit, sint entry)
{
    sint i;

    for (i = 0; i < entry; i++, phwxmit++) {
        spin_lock_init(&phwxmit->xmit_lock);
        _init_listhead(&phwxmit->pending);
        phwxmit->txcmdcnt = 0;
        phwxmit->accnt = 0;
    }
}

void xmitframe_xmitbuf_attach(struct xmit_frame *pxmitframe,
            struct xmit_buf *pxmitbuf)
{
    /* pxmitbuf attach to pxmitframe */
    pxmitframe->pxmitbuf = pxmitbuf;
    /* urb and irp connection */
    pxmitframe->pxmit_urb[0] = pxmitbuf->pxmit_urb[0];
    /* buffer addr assoc */
    pxmitframe->buf_addr = pxmitbuf->pbuf;
    /* pxmitframe attach to pxmitbuf */
    pxmitbuf->priv_data = pxmitframe;
}

/*
 * tx_action == 0 == no frames to transmit
 * tx_action > 0 ==> we have frames to transmit
 * tx_action < 0 ==> we have frames to transmit, but TXFF is not even enough
 *                       to transmit 1 frame.
 */

int r8712_pre_xmit(struct _adapter *padapter, struct xmit_frame *pxmitframe)
{
    unsigned long irqL;
    int ret;
    struct xmit_buf *pxmitbuf = NULL;
    struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
    struct pkt_attrib *pattrib = &pxmitframe->attrib;

    r8712_do_queue_select(padapter, pattrib);
    spin_lock_irqsave(&pxmitpriv->lock, irqL);
    if (r8712_txframes_sta_ac_pending(padapter, pattrib) > 0) {
        ret = false;
        r8712_xmit_enqueue(padapter, pxmitframe);
        spin_unlock_irqrestore(&pxmitpriv->lock, irqL);
        return ret;
    }
    pxmitbuf = r8712_alloc_xmitbuf(pxmitpriv);
    if (pxmitbuf == NULL) { /*enqueue packet*/
        ret = false;
        r8712_xmit_enqueue(padapter, pxmitframe);
        spin_unlock_irqrestore(&pxmitpriv->lock, irqL);
    } else { /*dump packet directly*/
        spin_unlock_irqrestore(&pxmitpriv->lock, irqL);
        ret = true;
        xmitframe_xmitbuf_attach(pxmitframe, pxmitbuf);
        r8712_xmit_direct(padapter, pxmitframe);
    }
    return ret;
}