ess.c

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/******************************************************************************
 *
 *  (C)Copyright 1998,1999 SysKonnect,
 *  a business unit of Schneider & Koch & Co. Datensysteme GmbH.
 *
 *  See the file "skfddi.c" for further information.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  The information in this file is provided "AS IS" without warranty.
 *
 ******************************************************************************/

/*
 * *******************************************************************
 * This SBA code implements the Synchronous Bandwidth Allocation
 * functions described in the "FDDI Synchronous Forum Implementer's
 * Agreement" dated December 1th, 1993.
 * *******************************************************************
 *
 *  PURPOSE: The purpose of this function is to control
 *       synchronous allocations on a single FDDI segment.
 *       Allocations are limited to the primary FDDI ring.
 *       The SBM provides recovery mechanisms to recover
 *       unused bandwidth also resolves T_Neg and
 *       reconfiguration changes. Many of the SBM state
 *       machine inputs are sourced by the underlying
 *       FDDI sub-system supporting the SBA application.
 *
 * *******************************************************************
 */

#include "h/types.h"
#include "h/fddi.h"
#include "h/smc.h"
#include "h/smt_p.h"


#ifndef SLIM_SMT

#ifdef ESS

#ifndef lint
static const char ID_sccs[] = "@(#)ess.c    1.10 96/02/23 (C) SK" ;
#define LINT_USE(x)
#else
#define LINT_USE(x) (x)=(x)
#endif
#define MS2BCLK(x)  ((x)*12500L)

/*
    -------------------------------------------------------------
    LOCAL VARIABLES:
    -------------------------------------------------------------
*/

static const u_short plist_raf_alc_res[] = { SMT_P0012, SMT_P320B, SMT_P320F,
                    SMT_P3210, SMT_P0019, SMT_P001A,
                    SMT_P001D, 0 } ;

static const u_short plist_raf_chg_req[] = { SMT_P320B, SMT_P320F, SMT_P3210,
                    SMT_P001A, 0 } ;

static const struct fddi_addr smt_sba_da = {{0x80,0x01,0x43,0x00,0x80,0x0C}} ;
static const struct fddi_addr null_addr = {{0,0,0,0,0,0}} ;

/*
    -------------------------------------------------------------
    GLOBAL VARIABLES:
    -------------------------------------------------------------
*/


/*
    -------------------------------------------------------------
    LOCAL FUNCTIONS:
    -------------------------------------------------------------
*/

static void ess_send_response(struct s_smc *smc, struct smt_header *sm,
                  int sba_cmd);
static void ess_config_fifo(struct s_smc *smc);
static void ess_send_alc_req(struct s_smc *smc);
static void ess_send_frame(struct s_smc *smc, SMbuf *mb);

/*
    -------------------------------------------------------------
    EXTERNAL FUNCTIONS:
    -------------------------------------------------------------
*/

/*
    -------------------------------------------------------------
    PUBLIC FUNCTIONS:
    -------------------------------------------------------------
*/

void ess_timer_poll(struct s_smc *smc);
void ess_para_change(struct s_smc *smc);
int ess_raf_received_pack(struct s_smc *smc, SMbuf *mb, struct smt_header *sm,
              int fs);
static int process_bw_alloc(struct s_smc *smc, long int payload, long int overhead);


/*
 * --------------------------------------------------------------------------
 *  End Station Support (ESS)
 * --------------------------------------------------------------------------
 */

/*
 * evaluate the RAF frame
 */
int ess_raf_received_pack(struct s_smc *smc, SMbuf *mb, struct smt_header *sm,
              int fs)
{
    void            *p ;        /* universal pointer */
    struct smt_p_0016   *cmd ;      /* para: command for the ESS */
    SMbuf           *db ;
    u_long          msg_res_type ;  /* recource type */
    u_long          payload, overhead ;
    int         local ;
    int         i ;

    /*
     * Message Processing Code
     */
     local = ((fs & L_INDICATOR) != 0) ;

    /*
     * get the resource type
     */
    if (!(p = (void *) sm_to_para(smc,sm,SMT_P0015))) {
        DB_ESS("ESS: RAF frame error, parameter type not found\n",0,0) ;
        return fs;
    }
    msg_res_type = ((struct smt_p_0015 *)p)->res_type ;

    /*
     * get the pointer to the ESS command
     */
    if (!(cmd = (struct smt_p_0016 *) sm_to_para(smc,sm,SMT_P0016))) {
        /*
         * error in frame: para ESS command was not found
         */
         DB_ESS("ESS: RAF frame error, parameter command not found\n",0,0);
         return fs;
    }

    DB_ESSN(2,"fc %x    ft %x\n",sm->smt_class,sm->smt_type) ;
    DB_ESSN(2,"ver %x   tran %lx\n",sm->smt_version,sm->smt_tid) ;
    DB_ESSN(2,"stn_id %s\n",addr_to_string(&sm->smt_source),0) ;

    DB_ESSN(2,"infolen %x   res %x\n",sm->smt_len, msg_res_type) ;
    DB_ESSN(2,"sbacmd %x\n",cmd->sba_cmd,0) ;

    /*
     * evaluate the ESS command
     */
    switch (cmd->sba_cmd) {

    /*
     * Process an ESS Allocation Request
     */
    case REQUEST_ALLOCATION :
        /*
         * check for an RAF Request (Allocation Request)
         */
        if (sm->smt_type == SMT_REQUEST) {
            /*
             * process the Allocation request only if the frame is
             * local and no static allocation is used
             */
            if (!local || smc->mib.fddiESSPayload)
                return fs;
            
            p = (void *) sm_to_para(smc,sm,SMT_P0019)  ;
            for (i = 0; i < 5; i++) {
                if (((struct smt_p_0019 *)p)->alloc_addr.a[i]) {
                    return fs;
                }
            }

            /*
             * Note: The Application should send a LAN_LOC_FRAME.
             *   The ESS do not send the Frame to the network!
             */
            smc->ess.alloc_trans_id = sm->smt_tid ;
            DB_ESS("ESS: save Alloc Req Trans ID %lx\n",sm->smt_tid,0);
            p = (void *) sm_to_para(smc,sm,SMT_P320F) ;
            ((struct smt_p_320f *)p)->mib_payload =
                smc->mib.a[PATH0].fddiPATHSbaPayload ;
            p = (void *) sm_to_para(smc,sm,SMT_P3210) ;
            ((struct smt_p_3210 *)p)->mib_overhead =
                smc->mib.a[PATH0].fddiPATHSbaOverhead ;
            sm->smt_dest = smt_sba_da ;

            if (smc->ess.local_sba_active)
                return fs | I_INDICATOR;

            if (!(db = smt_get_mbuf(smc)))
                return fs;

            db->sm_len = mb->sm_len ;
            db->sm_off = mb->sm_off ;
            memcpy(((char *)(db->sm_data+db->sm_off)),(char *)sm,
                (int)db->sm_len) ;
            dump_smt(smc,
                (struct smt_header *)(db->sm_data+db->sm_off),
                "RAF") ;
            smt_send_frame(smc,db,FC_SMT_INFO,0) ;
            return fs;
        }

        /*
         * The RAF frame is an Allocation Response !
         * check the parameters
         */
        if (smt_check_para(smc,sm,plist_raf_alc_res)) {
            DB_ESS("ESS: RAF with para problem, ignoring\n",0,0) ;
            return fs;
        }

        /*
         * VERIFY THE FRAME IS WELL BUILT:
         *
         *  1. path index = primary ring only
         *  2. resource type = sync bw only
         *  3. trans action id = alloc_trans_id
         *  4. reason code = success
         *
         * If any are violated, discard the RAF frame
         */
        if ((((struct smt_p_320b *)sm_to_para(smc,sm,SMT_P320B))->path_index
            != PRIMARY_RING) ||
            (msg_res_type != SYNC_BW) ||
        (((struct smt_p_reason *)sm_to_para(smc,sm,SMT_P0012))->rdf_reason
            != SMT_RDF_SUCCESS) ||
            (sm->smt_tid != smc->ess.alloc_trans_id)) {

            DB_ESS("ESS: Allocation Response not accepted\n",0,0) ;
            return fs;
        }

        /*
         * Extract message parameters
         */
        p = (void *) sm_to_para(smc,sm,SMT_P320F) ;
                if (!p) {
                        printk(KERN_ERR "ESS: sm_to_para failed");
                        return fs;
                }       
        payload = ((struct smt_p_320f *)p)->mib_payload ;
        p = (void *) sm_to_para(smc,sm,SMT_P3210) ;
                if (!p) {
                        printk(KERN_ERR "ESS: sm_to_para failed");
                        return fs;
                }       
        overhead = ((struct smt_p_3210 *)p)->mib_overhead ;

        DB_ESSN(2,"payload= %lx overhead= %lx\n",payload,overhead) ;

        /*
         * process the bandwidth allocation
         */
        (void)process_bw_alloc(smc,(long)payload,(long)overhead) ;

        return fs;
        /* end of Process Allocation Request */

    /*
     * Process an ESS Change Request
     */
    case CHANGE_ALLOCATION :
        /*
         * except only replies
         */
        if (sm->smt_type != SMT_REQUEST) {
            DB_ESS("ESS: Do not process Change Responses\n",0,0) ;
            return fs;
        }

        /*
         * check the para for the Change Request
         */
        if (smt_check_para(smc,sm,plist_raf_chg_req)) {
            DB_ESS("ESS: RAF with para problem, ignoring\n",0,0) ;
            return fs;
        }

        /*
         * Verify the path index and resource
         * type are correct. If any of
         * these are false, don't process this
         * change request frame.
         */
        if ((((struct smt_p_320b *)sm_to_para(smc,sm,SMT_P320B))->path_index
            != PRIMARY_RING) || (msg_res_type != SYNC_BW)) {
            DB_ESS("ESS: RAF frame with para problem, ignoring\n",0,0) ;
            return fs;
        }

        /*
         * Extract message queue parameters
         */
        p = (void *) sm_to_para(smc,sm,SMT_P320F) ;
        payload = ((struct smt_p_320f *)p)->mib_payload ;
        p = (void *) sm_to_para(smc,sm,SMT_P3210) ;
        overhead = ((struct smt_p_3210 *)p)->mib_overhead ;

        DB_ESSN(2,"ESS: Change Request from %s\n",
            addr_to_string(&sm->smt_source),0) ;
        DB_ESSN(2,"payload= %lx overhead= %lx\n",payload,overhead) ;

        /*
         * process the bandwidth allocation
         */
        if(!process_bw_alloc(smc,(long)payload,(long)overhead))
            return fs;

        /*
         * send an RAF Change Reply
         */
        ess_send_response(smc,sm,CHANGE_ALLOCATION) ;

        return fs;
        /* end of Process Change Request */

    /*
     * Process Report Response
     */
    case REPORT_ALLOCATION :
        /*
         * except only requests
         */
        if (sm->smt_type != SMT_REQUEST) {
            DB_ESS("ESS: Do not process a Report Reply\n",0,0) ;
            return fs;
        }

        DB_ESSN(2,"ESS: Report Request from %s\n",
            addr_to_string(&(sm->smt_source)),0) ;

        /*
         * verify that the resource type is sync bw only
         */
        if (msg_res_type != SYNC_BW) {
            DB_ESS("ESS: ignoring RAF with para problem\n",0,0) ;
            return fs;
        }

        /*
         * send an RAF Change Reply
         */
        ess_send_response(smc,sm,REPORT_ALLOCATION) ;

        return fs;
        /* end of Process Report Request */

    default:
        /*
         * error in frame
         */
        DB_ESS("ESS: ignoring RAF with bad sba_cmd\n",0,0) ;
        break ;
    }

    return fs;
}

/*
 * determines the synchronous bandwidth, set the TSYNC register and the
 * mib variables SBAPayload, SBAOverhead and fddiMACT-NEG.
 */
static int process_bw_alloc(struct s_smc *smc, long int payload, long int overhead)
{
    /*
     * determine the synchronous bandwidth (sync_bw) in bytes per T-NEG,
     * if the payload is greater than zero.
     * For the SBAPayload and the SBAOverhead we have the following
     * unite quations
     *            _       _
     *           |       bytes |
     *  SBAPayload = | 8000 ------ |
     *           |      s  |
     *            -       -
     *             _       _
     *            |  bytes  |
     *  SBAOverhead = | ------  |
     *            |  T-NEG  |
     *             -       -
     *
     * T-NEG is described by the equation:
     *
     *           (-) fddiMACT-NEG
     *  T-NEG =     -------------------
     *          12500000 1/s
     *
     * The number of bytes we are able to send is the payload
     * plus the overhead.
     *
     *            bytes    T-NEG SBAPayload 8000 bytes/s
     * sync_bw =  SBAOverhead ------ + -----------------------------
     *            T-NEG     T-NEG
     *
     *
     *                   1
     * sync_bw =  SBAOverhead + ---- (-)fddiMACT-NEG * SBAPayload
     *                  1562
     *
     */

    /*
     * set the mib attributes fddiPATHSbaOverhead, fddiPATHSbaPayload
     */
/*  if (smt_set_obj(smc,SMT_P320F,payload,S_SET)) {
        DB_ESS("ESS: SMT does not accept the payload value\n",0,0) ;
        return FALSE;
    }
    if (smt_set_obj(smc,SMT_P3210,overhead,S_SET)) {
        DB_ESS("ESS: SMT does not accept the overhead value\n",0,0) ;
        return FALSE;
    } */

    /* premliminary */
    if (payload > MAX_PAYLOAD || overhead > 5000) {
        DB_ESS("ESS: payload / overhead not accepted\n",0,0) ;
        return FALSE;
    }

    /*
     * start the iterative allocation process if the payload or the overhead
     * are smaller than the parsed values
     */
    if (smc->mib.fddiESSPayload &&
        ((u_long)payload != smc->mib.fddiESSPayload ||
        (u_long)overhead != smc->mib.fddiESSOverhead)) {
        smc->ess.raf_act_timer_poll = TRUE ;
        smc->ess.timer_count = 0 ;
    }

    /*
     * evulate the Payload
     */
    if (payload) {
        DB_ESSN(2,"ESS: turn SMT_ST_SYNC_SERVICE bit on\n",0,0) ;
        smc->ess.sync_bw_available = TRUE ;

        smc->ess.sync_bw = overhead -
            (long)smc->mib.m[MAC0].fddiMACT_Neg *
            payload / 1562 ;
    }
    else {
        DB_ESSN(2,"ESS: turn SMT_ST_SYNC_SERVICE bit off\n",0,0) ;
        smc->ess.sync_bw_available = FALSE ;
        smc->ess.sync_bw = 0 ;
        overhead = 0 ;
    }

    smc->mib.a[PATH0].fddiPATHSbaPayload = payload ;
    smc->mib.a[PATH0].fddiPATHSbaOverhead = overhead ;


    DB_ESSN(2,"tsync = %lx\n",smc->ess.sync_bw,0) ;

    ess_config_fifo(smc) ;
    set_formac_tsync(smc,smc->ess.sync_bw) ;
    return TRUE;
}

static void ess_send_response(struct s_smc *smc, struct smt_header *sm,
                  int sba_cmd)
{
    struct smt_sba_chg  *chg ;
    SMbuf           *mb ;
    void            *p ;

    /*
     * get and initialize the response frame
     */
    if (sba_cmd == CHANGE_ALLOCATION) {
        if (!(mb=smt_build_frame(smc,SMT_RAF,SMT_REPLY,
                sizeof(struct smt_sba_chg))))
                return ;
    }
    else {
        if (!(mb=smt_build_frame(smc,SMT_RAF,SMT_REPLY,
                sizeof(struct smt_sba_rep_res))))
                return ;
    }

    chg = smtod(mb,struct smt_sba_chg *) ;
    chg->smt.smt_tid = sm->smt_tid ;
    chg->smt.smt_dest = sm->smt_source ;

    /* set P15 */
    chg->s_type.para.p_type = SMT_P0015 ;
    chg->s_type.para.p_len = sizeof(struct smt_p_0015) - PARA_LEN ;
    chg->s_type.res_type = SYNC_BW ;

    /* set P16 */
    chg->cmd.para.p_type = SMT_P0016 ;
    chg->cmd.para.p_len = sizeof(struct smt_p_0016) - PARA_LEN ;
    chg->cmd.sba_cmd = sba_cmd ;

    /* set P320B */
    chg->path.para.p_type = SMT_P320B ;
    chg->path.para.p_len = sizeof(struct smt_p_320b) - PARA_LEN ;
    chg->path.mib_index = SBAPATHINDEX ;
    chg->path.path_pad = 0;
    chg->path.path_index = PRIMARY_RING ;

    /* set P320F */
    chg->payload.para.p_type = SMT_P320F ;
    chg->payload.para.p_len = sizeof(struct smt_p_320f) - PARA_LEN ;
    chg->payload.mib_index = SBAPATHINDEX ;
    chg->payload.mib_payload = smc->mib.a[PATH0].fddiPATHSbaPayload ;

    /* set P3210 */
    chg->overhead.para.p_type = SMT_P3210 ;
    chg->overhead.para.p_len = sizeof(struct smt_p_3210) - PARA_LEN ;
    chg->overhead.mib_index = SBAPATHINDEX ;
    chg->overhead.mib_overhead = smc->mib.a[PATH0].fddiPATHSbaOverhead ;

    if (sba_cmd == CHANGE_ALLOCATION) {
        /* set P1A */
        chg->cat.para.p_type = SMT_P001A ;
        chg->cat.para.p_len = sizeof(struct smt_p_001a) - PARA_LEN ;
        p = (void *) sm_to_para(smc,sm,SMT_P001A) ;
        chg->cat.category = ((struct smt_p_001a *)p)->category ;
    }
    dump_smt(smc,(struct smt_header *)chg,"RAF") ;
    ess_send_frame(smc,mb) ;
}

void ess_timer_poll(struct s_smc *smc)
{
    if (!smc->ess.raf_act_timer_poll)
        return ;

    DB_ESSN(2,"ESS: timer_poll\n",0,0) ;

    smc->ess.timer_count++ ;
    if (smc->ess.timer_count == 10) {
        smc->ess.timer_count = 0 ;
        ess_send_alc_req(smc) ;
    }
}

static void ess_send_alc_req(struct s_smc *smc)
{
    struct smt_sba_alc_req *req ;
    SMbuf   *mb ;

    /*
     * send never allocation request where the requested payload and
     * overhead is zero or deallocate bandwidth when no bandwidth is
     * parsed
     */
    if (!smc->mib.fddiESSPayload) {
        smc->mib.fddiESSOverhead = 0 ;
    }
    else {
        if (!smc->mib.fddiESSOverhead)
            smc->mib.fddiESSOverhead = DEFAULT_OV ;
    }

    if (smc->mib.fddiESSOverhead ==
        smc->mib.a[PATH0].fddiPATHSbaOverhead &&
        smc->mib.fddiESSPayload ==
        smc->mib.a[PATH0].fddiPATHSbaPayload){
        smc->ess.raf_act_timer_poll = FALSE ;
        smc->ess.timer_count = 7 ;  /* next RAF alc req after 3 s */
        return ;
    }
    
    /*
     * get and initialize the response frame
     */
    if (!(mb=smt_build_frame(smc,SMT_RAF,SMT_REQUEST,
            sizeof(struct smt_sba_alc_req))))
            return ;
    req = smtod(mb,struct smt_sba_alc_req *) ;
    req->smt.smt_tid = smc->ess.alloc_trans_id = smt_get_tid(smc) ;
    req->smt.smt_dest = smt_sba_da ;

    /* set P15 */
    req->s_type.para.p_type = SMT_P0015 ;
    req->s_type.para.p_len = sizeof(struct smt_p_0015) - PARA_LEN ;
    req->s_type.res_type = SYNC_BW ;

    /* set P16 */
    req->cmd.para.p_type = SMT_P0016 ;
    req->cmd.para.p_len = sizeof(struct smt_p_0016) - PARA_LEN ;
    req->cmd.sba_cmd = REQUEST_ALLOCATION ;

    /*
     * set the parameter type and parameter length of all used
     * parameters
     */

    /* set P320B */
    req->path.para.p_type = SMT_P320B ;
    req->path.para.p_len = sizeof(struct smt_p_320b) - PARA_LEN ;
    req->path.mib_index = SBAPATHINDEX ;
    req->path.path_pad = 0;
    req->path.path_index = PRIMARY_RING ;

    /* set P0017 */
    req->pl_req.para.p_type = SMT_P0017 ;
    req->pl_req.para.p_len = sizeof(struct smt_p_0017) - PARA_LEN ;
    req->pl_req.sba_pl_req = smc->mib.fddiESSPayload -
        smc->mib.a[PATH0].fddiPATHSbaPayload ;

    /* set P0018 */
    req->ov_req.para.p_type = SMT_P0018 ;
    req->ov_req.para.p_len = sizeof(struct smt_p_0018) - PARA_LEN ;
    req->ov_req.sba_ov_req = smc->mib.fddiESSOverhead -
        smc->mib.a[PATH0].fddiPATHSbaOverhead ;

    /* set P320F */
    req->payload.para.p_type = SMT_P320F ;
    req->payload.para.p_len = sizeof(struct smt_p_320f) - PARA_LEN ;
    req->payload.mib_index = SBAPATHINDEX ;
    req->payload.mib_payload = smc->mib.a[PATH0].fddiPATHSbaPayload ;

    /* set P3210 */
    req->overhead.para.p_type = SMT_P3210 ;
    req->overhead.para.p_len = sizeof(struct smt_p_3210) - PARA_LEN ;
    req->overhead.mib_index = SBAPATHINDEX ;
    req->overhead.mib_overhead = smc->mib.a[PATH0].fddiPATHSbaOverhead ;

    /* set P19 */
    req->a_addr.para.p_type = SMT_P0019 ;
    req->a_addr.para.p_len = sizeof(struct smt_p_0019) - PARA_LEN ;
    req->a_addr.sba_pad = 0;
    req->a_addr.alloc_addr = null_addr ;

    /* set P1A */
    req->cat.para.p_type = SMT_P001A ;
    req->cat.para.p_len = sizeof(struct smt_p_001a) - PARA_LEN ;
    req->cat.category = smc->mib.fddiESSCategory ;

    /* set P1B */
    req->tneg.para.p_type = SMT_P001B ;
    req->tneg.para.p_len = sizeof(struct smt_p_001b) - PARA_LEN ;
    req->tneg.max_t_neg = smc->mib.fddiESSMaxTNeg ;

    /* set P1C */
    req->segm.para.p_type = SMT_P001C ;
    req->segm.para.p_len = sizeof(struct smt_p_001c) - PARA_LEN ;
    req->segm.min_seg_siz = smc->mib.fddiESSMinSegmentSize ;

    dump_smt(smc,(struct smt_header *)req,"RAF") ;
    ess_send_frame(smc,mb) ;
}

static void ess_send_frame(struct s_smc *smc, SMbuf *mb)
{
    /*
     * check if the frame must be send to the own ESS
     */
    if (smc->ess.local_sba_active) {
        /*
         * Send the Change Reply to the local SBA
         */
        DB_ESS("ESS:Send to the local SBA\n",0,0) ;
        if (!smc->ess.sba_reply_pend)
            smc->ess.sba_reply_pend = mb ;
        else {
            DB_ESS("Frame is lost - another frame was pending\n",0,0);
            smt_free_mbuf(smc,mb) ;
        }
    }
    else {
        /*
         * Send the SBA RAF Change Reply to the network
         */
        DB_ESS("ESS:Send to the network\n",0,0) ;
        smt_send_frame(smc,mb,FC_SMT_INFO,0) ;
    }
}

void ess_para_change(struct s_smc *smc)
{
    (void)process_bw_alloc(smc,(long)smc->mib.a[PATH0].fddiPATHSbaPayload,
        (long)smc->mib.a[PATH0].fddiPATHSbaOverhead) ;
}

static void ess_config_fifo(struct s_smc *smc)
{
    /*
     * if nothing to do exit 
     */
    if (smc->mib.a[PATH0].fddiPATHSbaPayload) {
        if (smc->hw.fp.fifo.fifo_config_mode & SYNC_TRAFFIC_ON &&
            (smc->hw.fp.fifo.fifo_config_mode&SEND_ASYNC_AS_SYNC) ==
            smc->mib.fddiESSSynchTxMode) {
            return ;
        }
    }
    else {
        if (!(smc->hw.fp.fifo.fifo_config_mode & SYNC_TRAFFIC_ON)) {
            return ;
        }
    }

    /*
     * split up the FIFO and reinitialize the queues
     */
    formac_reinit_tx(smc) ;
}

#endif /* ESS */

#endif  /* no SLIM_SMT */