gdth.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

            for (b=0,t=0; b<ha->bus_cnt; ++b) {
                for (t=0; t<MAXID; ++t) {
                    if (ha->id[b][t].type == EMPTY_DTYP) {
                        pos_found = TRUE;
                        break;
                    }
                }
                if (pos_found)
                    break;
            }
            TRACE(("gdth_search_dr() drive %d free pos at bus/id %d/%d\n",
                         i,b,t));

            ha->id[b][t].type      = CACHE_DTYP;
            ha->id[b][t].devtype   = 0;
            ha->id[b][t].size      = ha->info;
            ha->id[b][t].hostdrive = i;

            /* evaluate mapping (sectors per head, heads per cylinder) */
	    ha->id[b][t].size &= ~SECS32;
	    if (ha->info2 == 0) {
		drv_cyls = ha->id[b][t].size /HEADS/SECS;
		if (drv_cyls <= MAXCYLS) {
		    drv_hds = HEADS;
		    drv_secs= SECS;
		} else {                            /* too high for 64*32 */
		    drv_cyls = ha->id[b][t].size /MEDHEADS/MEDSECS;
		    if (drv_cyls <= MAXCYLS) {
			drv_hds = MEDHEADS;
			drv_secs= MEDSECS;
		    } else {                        /* too high for 127*63 */
			drv_cyls = ha->id[b][t].size /BIGHEADS/BIGSECS;
			drv_hds = BIGHEADS;
			drv_secs= BIGSECS;
		    }
		}
            } else {
		drv_hds = ha->info2 & 0xff;
		drv_secs = (ha->info2 >> 8) & 0xff;
		drv_cyls = ha->id[b][t].size /drv_hds/drv_secs;
	    }
            ha->id[b][t].heads = (unchar)drv_hds;
            ha->id[b][t].secs  = (unchar)drv_secs;
            /* round size */
            ha->id[b][t].size  = drv_cyls * drv_hds * drv_secs;
            TRACE2(("gdth_search_dr() cdr. %d size %ld hds %ld scs %ld\n",
                   i,ha->id[b][t].size,drv_hds,drv_secs));
            
            /* get informations about device */
            if (gdth_internal_cmd(hanum,CACHESERVICE,GDT_DEVTYPE,i,
                                  0,0)) {
                TRACE(("gdth_search_dr() cache drive %d devtype %ld\n",
                       i,ha->info));
                ha->id[b][t].devtype = (ushort)ha->info;
            }
        }
    }

    TRACE(("gdth_search_drives() OK\n"));
    return 1;
}


/* command queueing/sending functions */

static void gdth_putq(int hanum,Scsi_Cmnd *scp,unchar priority)
{
    register gdth_ha_str *ha;
    register Scsi_Cmnd *pscp;
    register Scsi_Cmnd *nscp;
    ulong flags;
    unchar b, t;

    TRACE(("gdth_putq() priority %d\n",priority));
    save_flags(flags);
    cli();

    ha = HADATA(gdth_ctr_tab[hanum]);
    scp->SCp.this_residual = (int)priority;
    gdth_update_timeout(hanum, scp, scp->timeout_per_command * 6);
#if LINUX_VERSION_CODE >= 0x020000
    b = scp->channel;
#else
    b = NUMDATA(nscp->host)->busnum;
#endif
    t = scp->target;
#if LINUX_VERSION_CODE >= 0x010300
    if (priority >= DEFAULT_PRI && ha->id[b][t].lock) {
        TRACE2(("gdth_putq(): locked IO -> update_timeout()\n"));
        scp->SCp.buffers_residual = gdth_update_timeout(hanum, scp, 0);
    }
#endif

    if (ha->req_first==NULL) {
        ha->req_first = scp;                    /* queue was empty */
        scp->SCp.ptr = NULL;
    } else {                                    /* queue not empty */
        pscp = ha->req_first;
        nscp = (Scsi_Cmnd *)pscp->SCp.ptr;
        /* priority: 0-highest,..,0xff-lowest */
        while (nscp && (unchar)nscp->SCp.this_residual <= priority) {
            pscp = nscp;
            nscp = (Scsi_Cmnd *)pscp->SCp.ptr;
        }
        pscp->SCp.ptr = (char *)scp;
        scp->SCp.ptr  = (char *)nscp;
    }
    restore_flags(flags);

#ifdef GDTH_STATISTICS
    flags = 0;
    for (nscp=ha->req_first; nscp; nscp=(Scsi_Cmnd*)nscp->SCp.ptr)
        ++flags;
    if (max_rq < flags) {
        max_rq = flags;
        TRACE3(("GDT: max_rq = %d\n",(ushort)max_rq));
    }
#endif
}

static void gdth_next(int hanum)
{
    register gdth_ha_str *ha;
    register Scsi_Cmnd *pscp;
    register Scsi_Cmnd *nscp;
    unchar b, t, next_cmd, firsttime;
    ushort hdrive;
    ulong flags;
    int cmd_index;

    TRACE(("gdth_next() hanum %d\n",hanum));
    save_flags(flags);
    cli();

    ha = HADATA(gdth_ctr_tab[hanum]);
    ha->cmd_cnt = ha->cmd_offs_dpmem = 0;
    next_cmd = firsttime = TRUE;
    cmd_index = 0;

    for (nscp = pscp = ha->req_first; nscp; nscp = (Scsi_Cmnd *)nscp->SCp.ptr) {
        if (nscp != pscp && nscp != (Scsi_Cmnd *)pscp->SCp.ptr)
            pscp = (Scsi_Cmnd *)pscp->SCp.ptr;
#if LINUX_VERSION_CODE >= 0x020000
        b = nscp->channel;
#else
        b = NUMDATA(nscp->host)->busnum;
#endif
        t = nscp->target;
        if (nscp->SCp.this_residual < DEFAULT_PRI || !ha->id[b][t].lock) {

            if (firsttime) {
                if (gdth_test_busy(hanum)) {        /* controller busy ? */
                    TRACE(("gdth_next() controller %d busy !\n",hanum));
                    if (!gdth_polling) {
                        restore_flags(flags);
                        return;
                    }
                    while (gdth_test_busy(hanum))
                        gdth_delay(1);
                }
                firsttime = FALSE;
            }

#if LINUX_VERSION_CODE >= 0x010300
            if (nscp->done == gdth_scsi_done) {
                if (!(cmd_index=gdth_special_cmd(hanum,nscp,b)))
                    next_cmd = FALSE;
            } else
#endif
            if (ha->id[b][t].type != CACHE_DTYP) {
                if (!(cmd_index=gdth_fill_raw_cmd(hanum,nscp,b)))
                    next_cmd = FALSE;
            } else {
                hdrive = ha->id[b][t].hostdrive;
                switch (nscp->cmnd[0]) {
                  case TEST_UNIT_READY:
                  case INQUIRY:
                  case REQUEST_SENSE:
                  case READ_CAPACITY:
                  case VERIFY:
                  case START_STOP:
                  case MODE_SENSE:
                    TRACE2(("cache cmd %x/%x/%x/%x/%x/%x\n",nscp->cmnd[0],
                        nscp->cmnd[1],nscp->cmnd[2],nscp->cmnd[3],
                        nscp->cmnd[4],nscp->cmnd[5]));
                        gdth_internal_cache_cmd(hanum,nscp,b,&flags);
                    break;

                  case ALLOW_MEDIUM_REMOVAL:
                    TRACE2(("cache cmd %x/%x/%x/%x/%x/%x\n",nscp->cmnd[0],
                        nscp->cmnd[1],nscp->cmnd[2],nscp->cmnd[3],
                        nscp->cmnd[4],nscp->cmnd[5]));
                    if ( (nscp->cmnd[4]&1) && !(ha->id[b][t].devtype&1) ) {
                        TRACE2(("Prevent r. nonremov. drive->do nothing\n"));
                        nscp->result = DID_OK << 16;
                        restore_flags( flags );
                        if (!nscp->SCp.have_data_in)
                            nscp->SCp.have_data_in++;
                        else
                            nscp->scsi_done(nscp);
                        save_flags( flags );
                        cli();
                    } else {
                        nscp->cmnd[3] = (ha->id[b][t].devtype&1) ? 1:0;
                        TRACE2(("Prevent/allow r. %d rem. drive %d\n",
                            nscp->cmnd[4],nscp->cmnd[3]));
                        if (!(cmd_index=gdth_fill_cache_cmd(hanum,nscp,hdrive)))
                            next_cmd = FALSE;
                    }
                    break;

                  case READ_6:
                  case WRITE_6:
                  case READ_10:
                  case WRITE_10:
                    if (!(cmd_index=gdth_fill_cache_cmd(hanum,nscp,hdrive)))
                        next_cmd = FALSE;
                    break;

                  default:
                    TRACE2(("cache cmd %x/%x/%x/%x/%x/%x\n",nscp->cmnd[0],
                        nscp->cmnd[1],nscp->cmnd[2],nscp->cmnd[3],
                        nscp->cmnd[4],nscp->cmnd[5]));
                    printk("GDT: Unknown SCSI command 0x%x to cache service !\n",
                       nscp->cmnd[0]);
                    nscp->result = DID_ABORT << 16;
                    restore_flags( flags );
                    if (!nscp->SCp.have_data_in)
                        nscp->SCp.have_data_in++;
                    else
                        nscp->scsi_done(nscp);
                    save_flags( flags );
                    cli();
                    break;
                }
            }

            if (!next_cmd)
                break;
            if (nscp == ha->req_first)
                ha->req_first = pscp = (Scsi_Cmnd *)nscp->SCp.ptr;
            else
                pscp->SCp.ptr = nscp->SCp.ptr;
            if (gdth_polling)
                break;
        }
    }

    if (ha->cmd_cnt > 0) {
        gdth_release_event(hanum);
    }

    restore_flags(flags);

    if (gdth_polling && ha->cmd_cnt > 0) {
        if (!gdth_wait(hanum,cmd_index,POLL_TIMEOUT))
            printk("GDT: Controller %d: Command %d timed out !\n",
                   hanum,cmd_index);
    }
}
    
static void gdth_copy_internal_data(Scsi_Cmnd *scp,char *buffer,ushort count)
{
    ushort cpcount,i;
    ushort cpsum,cpnow;
    struct scatterlist *sl;

    cpcount = count<=(ushort)scp->bufflen ? count:(ushort)scp->bufflen;
    if (scp->use_sg) {
        sl = (struct scatterlist *)scp->request_buffer;
        for (i=0,cpsum=0; i<scp->use_sg; ++i,++sl) {
            cpnow = (ushort)sl->length;
            TRACE(("copy_internal() now %d sum %d count %d %d\n",
                          cpnow,cpsum,cpcount,(ushort)scp->bufflen));
            if (cpsum+cpnow > cpcount) 
                cpnow = cpcount - cpsum;
            cpsum += cpnow;
            memcpy((char*)sl->address,buffer,cpnow);
            if (cpsum == cpcount)
                break;
            buffer += cpnow;
        }
    } else {
        TRACE(("copy_internal() count %d\n",cpcount));
        memcpy((char*)scp->request_buffer,buffer,cpcount);
    }
}

static int gdth_internal_cache_cmd(int hanum,Scsi_Cmnd *scp,
                                   unchar b,ulong *flags)
{
    register gdth_ha_str *ha;
    ushort hdrive;
    unchar t;
    gdth_inq_data inq;
    gdth_rdcap_data rdc;
    gdth_sense_data sd;
    gdth_modep_data mpd;

    ha = HADATA(gdth_ctr_tab[hanum]);
    t  = scp->target;
    hdrive = ha->id[b][t].hostdrive;
    TRACE(("gdth_internal_cache_cmd() cmd 0x%x hdrive %d\n",
                 scp->cmnd[0],hdrive));

    if (scp->lun !=0)
        scp->result = DID_BAD_TARGET << 16;
    else {
        switch (scp->cmnd[0]) {
          case TEST_UNIT_READY:
          case VERIFY:
          case START_STOP:
            TRACE2(("Test/Verify/Start hdrive %d\n",hdrive));
            break;

          case INQUIRY:
            TRACE2(("Inquiry hdrive %d devtype %d\n",
                          hdrive,ha->id[b][t].devtype));
            inq.type_qual = (ha->id[b][t].devtype&4) ? TYPE_ROM:TYPE_DISK;
            /* you can here set all disks to removable, if you want to do
               a flush using the ALLOW_MEDIUM_REMOVAL command */
            inq.modif_rmb = ha->id[b][t].devtype&1 ? 0x80:0x00;
            inq.version   = 2;
            inq.resp_aenc = 2;
            inq.add_length= 32;
            strcpy(inq.vendor,"ICP    ");
            sprintf(inq.product,"Host Drive  #%02d",hdrive);
            strcpy(inq.revision,"   ");
            gdth_copy_internal_data(scp,(char*)&inq,sizeof(gdth_inq_data));
            break;

          case REQUEST_SENSE:
            TRACE2(("Request sense hdrive %d\n",hdrive));
            sd.errorcode = 0x70;
            sd.segno     = 0x00;
            sd.key       = NO_SENSE;
            sd.info      = 0;
            sd.add_length= 0;
            gdth_copy_internal_data(scp,(char*)&sd,sizeof(gdth_sense_data));
            break;

          case MODE_SENSE:
            TRACE2(("Mode sense hdrive %d\n",hdrive));
            memset((char*)&mpd,0,sizeof(gdth_modep_data));
            mpd.hd.data_length = sizeof(gdth_modep_data);
            mpd.hd.dev_par     = (ha->id[b][t].devtype&2) ? 0x80:0;
            mpd.hd.bd_length   = sizeof(mpd.bd);
            mpd.bd.block_length[0] = (SECTOR_SIZE & 0x00ff0000) >> 16;
            mpd.bd.block_length[1] = (SECTOR_SIZE & 0x0000ff00) >> 8;
            mpd.bd.block_length[2] = (SECTOR_SIZE & 0x000000ff);
            gdth_copy_internal_data(scp,(char*)&mpd,sizeof(gdth_modep_data));
            break;

          case READ_CAPACITY:
            TRACE2(("Read capacity hdrive %d\n",hdrive));
            rdc.last_block_no = ntohl(ha->id[b][t].size-1);
            rdc.block_length  = ntohl(SECTOR_SIZE);
            gdth_copy_internal_data(scp,(char*)&rdc,sizeof(gdth_rdcap_data));
            break;

          default:
            TRACE2(("Internal cache cmd 0x%x unknown\n",scp->cmnd[0]));
            break;
        }
        scp->result = DID_OK << 16;
    }

    restore_flags(*flags);
    if (!scp->SCp.have_data_in)
        scp->SCp.have_data_in++;
    else
        scp->scsi_done(scp);
    save_flags(*flags);
    cli();
    return 1;
}
    
static int gdth_fill_cache_cmd(int hanum,Scsi_Cmnd *scp,ushort hdrive)
{
    register gdth_ha_str *ha;
    register gdth_cmd_str *cmdp;
    struct scatterlist *sl;
    ushort i;
    int cmd_in