mscp_tape.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

 *   Return	
 *   Values:
 */

int 
tmscpwrite( dev, uio )

	dev_t		dev;
	struct	uio 	*uio;

{

	register UNITB	*up;

	/* If there is no known unit corresponding to the device
	 * number, return an error.
	 */
	if(( up = Dev_to_Tunitb( dev )) == NULL ) {
		Dprint8("write: ENXIO return, unknown unit\n");
		return( ENXIO );
	}

	/* Invoke physio to fire off the strategy routine and return
	 * the resulting status.
	 */
	return( physio( tmscpstrategy, &up->rawbuf, dev, B_WRITE, minphys, uio ));
}


/*
 *
 *   Name:	tmscpioctl	- Process I/O Control Functions
 *
 *   Abstract:	
 *
 *   Inputs:
 *
 *   Outputs:
 *
 *
 *   Return	NONE
 *   Values:
 */


int
tmscpioctl(dev, cmd, data, flag)

    dev_t		dev;
    int			cmd;
    caddr_t		data;
    int			flag;

{

	register UNITB	*up;
	REQB		*rp;
	struct uba_device *ui;  /* ptr to the uba device structure */

	CONNB		*cp;
        struct mtop	*mtop;      /* mag tape cmd op to perform */
        struct mtget	*mtget;    /* mag tape struct to get info in */
        struct devget	*devget;  /* device struct for status info */
	int		unit;
	int		retries;
	int		s;

	Dprint6("tmscpioctl\n");

    /* If there is no known unit corresponding to the device
     * number, return an error.
     */
    if(( up = Dev_to_Tunitb( dev )) == NULL ) {
	Dprint8("ioctl: ENXIO return, unknown unit\n");
	return( ENXIO );
    }

    cp = up->connb;
    unit = up->unit;
    ui = up->ubdev;

    /* Set BOM if at position 0 for status ioctl's
     */
    if(up->tms_position == 0)
	up->tms_flags |= DEV_BOM;
    else
	up->tms_flags &= ~DEV_BOM;

    /* tms_status is used to determine the status of the requested ioctl
     * except for the case of MTIOCGET.  This means we need to init the field
     * in all cases except MTIOCGET.  For MTIOCGET we want to return the status
     * of the last command issued.
     */
    if (cmd != MTIOCGET)
                up->tms_status = ~(MSCP_ST_SUCC);

    switch( cmd ) {
        case MTIOCTOP:  /* tape operation */
	Dprint4("MTIOCTOP\n");
                mtop = (struct mtop *)data;
                switch (mtop->mt_op) {

/*		The ERASE and ABORT ioctls work but at this time there are
/*		no user level functions which call them
/*
/*		case MTERASE:	/* Issue tape erase.  It will erase from
/*				 * current tape position to physical
/*				 * end of tape.   The rewinds to BOT.
/*				 * Would use timeout of RETRY_REPOS_COUNT.
/*				 */
/*			Dprint4("MTERASE\n");
/*			/* Check to make sure that the unit 
/*			* is online.
/*			*/
/*			if( up->flags.online ) {
/*				(void) mscp_alloc_reqb( up, NULL, 
/*				    tmscp_era_states, (u_long) 0, (u_long) 0 );
/*			}
/*			break;
/*
/*
/*		case MTABORT:	/* Issue abort command.  It will abort the
/*				 * last long running tape command issued.
/*				 * NOTE: The present abort scheme is 
/*				 * insuficient if more than one command is
/*				 * outstanding or if the command intended to be
/*				 * aborted was not the most recent command.
/*				 */
/*			Dprint4("MTABORT\n");
/*			/* Check to make sure that the unit 
/*			* is online.
/*			*/
/*			if( up->flags.online ) {
/*
/*
/*
/*				/* Allocate a request block and start the data transfer.
/*				*/
/*				(void) mscp_alloc_reqb( up, NULL, tmscp_abo_states, (u_long) 0, (u_long) 0 );
/*			}
/*			break;
/*
 */
                case MTWEOF:	/* Write two EOF's and reposition back 1 
				 * this has the effect of writing a EOT
				 * but if a new file is put on the tape
				 * (assume no rewind) the second EOF is 
				 * over written making it a real EOF and
				 * not an EOT.
				 *
				 * Note: ts.c only writes one tape mark.  This
				 * makes behavior different if a reposition is
				 * done after this command.  If a close is done
				 * after MTWEOF then there will really be 3
				 * tape marks on the media.  This is a potential
				 * violation of ansi specs.  This routine never
				 * looks at the count parameter from the user.
				 */
			Dprint4("MTWEOF\n");
			/* Write the first tape mark
			 */
			up->Tflags.tms_wait = 1;
			rp = (REQB *) mscp_alloc_reqb( up, NULL, tmscp_wtm_states, (u_long) 0, (u_long) 0 );
			retries = RETRY_COUNT;
			while( up->Tflags.tms_wait  && ( --retries >= 0 ) ) {
				timeout( wakeup, ( caddr_t )rp, hz );
				( void )sleep(( caddr_t )rp, PSWP+1 );
				untimeout(wakeup, ( caddr_t )rp, hz );
			}
			Time_Check(up->Tflags.tms_wait, retries, "MTWEOF 1");
			up->Tflags.tms_wait = 0;
              
	                  /* Check the status for the command that was issued and return fail code
	                   * if the status is not success.
	                   */
	                  if ( up->tms_status != MSCP_ST_SUCC) 
	              		return(EIO);
	
			/* Write the second tape mark
			 * Initilize command status to prevent masking of error.
			 */
			up->Tflags.tms_wait = 1;
			up->tms_status = ~(MSCP_ST_SUCC);
			rp = (REQB *) mscp_alloc_reqb( up, NULL, tmscp_wtm_states, (u_long) 0, (u_long) 0 );
			retries = RETRY_COUNT;
			while( up->Tflags.tms_wait  && ( --retries >= 0 ) ) {
				timeout( wakeup, ( caddr_t )rp, hz );
				( void )sleep(( caddr_t )rp, PSWP+1 );
				untimeout(wakeup, ( caddr_t )rp, hz );
			}
			Time_Check(up->Tflags.tms_wait, retries, "MTWEOF 2");
			up->Tflags.tms_wait = 0;
              
	                /* Check the status for the command that was issued and return fail code
	                * if the status is not success.
	                */
	                if ( up->tms_status != MSCP_ST_SUCC) 
	              		return(EIO);
			up->Tflags.tms_write=0;
	
			/*
			 * Success of 2 consecutive wtm's will cause the
			 * controller to flush it's cache. Clear tms_cach_write
			 * to indicate that there are no write records pending
			 * in the controller's write cache.
			 */
			up->Tflags.tms_cach_write = 0;

			/* Now reposition back over the last tape mark 
			 * Initilize command status to prevent masking of error.
			 */
			up->Tflags.tms_wait = 1;
			up->tms_status = ~(MSCP_ST_SUCC);
			rp = (REQB *) mscp_alloc_reqb( up, NULL, tmscp_rpo_states, (u_long) (MSCP_MD_OBJCT | MSCP_MD_REVRS), (u_long) 1 );
			retries = RETRY_COUNT;
			while( up->Tflags.tms_wait  && ( --retries >= 0 ) ) {
				timeout( wakeup, ( caddr_t )rp, hz );
				( void )sleep(( caddr_t )rp, PSWP+1 );
				untimeout(wakeup, ( caddr_t )rp, hz );
			}
			Time_Check(up->Tflags.tms_wait, retries, "MTWEOF 3");
			up->Tflags.tms_wait = 0;
              
	                /* Check the status for the command that was issued and return fail code
	                * if the status is not success.
	                */
	                if ( up->tms_status != MSCP_ST_SUCC) 
	              		return(EIO);
			else
				return(0);

                case MTFSF: 	/* Reposition command forward EOF count
			 	 */
			Dprint4("MTFSF\n");
			/* Check to make sure that the unit 
			 * is online.
			 */
			if( up->flags.online ) {
				/* Allocate a request block and start the data transfer.
				*/
				up->Tflags.tms_wait = 1;
				rp = (REQB *) mscp_alloc_reqb( up, NULL, tmscp_rpo_states, (u_long) 0, (u_long) mtop->mt_count );
				retries = RETRY_REPOS_COUNT;
				while( up->Tflags.tms_wait  && ( --retries >= 0 ) ) {
					timeout( wakeup, ( caddr_t )rp, hz );
					( void )sleep(( caddr_t )rp, PSWP+1 );
					untimeout(wakeup, ( caddr_t )rp, hz );
				}
				Time_Check(up->Tflags.tms_wait,retries,"MTFSF");
				up->Tflags.tms_wait = 0;
			}
              
	                /* Check the status for the command that was issued and return fail code
	                * if the status is not success.
	                */
	                if ( up->tms_status != MSCP_ST_SUCC) 
	              		return(EIO);
			else
				return(0);

		case MTBSF: 	/* Reposition command backward EOF count 
			 	 */
			Dprint4("MTBSF\n");

			/* Check to make sure that the unit 
			 * is online.
			 */
			if( up->flags.online ) {
				/* Allocate a request block and start the data transfer.
				*/
				up->Tflags.tms_wait = 1;
				rp = (REQB *) mscp_alloc_reqb( up, NULL, tmscp_rpo_states, (u_long) MSCP_MD_REVRS, (u_long) mtop->mt_count );
				retries = RETRY_REPOS_COUNT;
				while( up->Tflags.tms_wait  && ( --retries >= 0 ) ) {
					timeout( wakeup, ( caddr_t )rp, hz );
					( void )sleep(( caddr_t )rp, PSWP+1 );
					untimeout(wakeup, ( caddr_t )rp, hz );
				}
				Time_Check(up->Tflags.tms_wait,retries,"MTBSF");
				up->Tflags.tms_wait = 0;
			}
              
	                /* Check the status for the command that was issued and return fail code
	                * if the status is not success.
	                */
	                if ( up->tms_status != MSCP_ST_SUCC) 
	              		return(EIO);
			else
				return(0);

                case MTFSR:  	/* Reposition command forward count 
			 	 */
			Dprint4("MTFSR\n");
			/* Check to make sure that the unit 
			* is online.
			*/
			if( up->flags.online ) {
				/* Allocate a request block and start the data 
				 * transfer.
				 * To setup the reposition command to move
				 * RECORDS call the tmscp_rec_states instead
				 * of the tmscp_rpo_states.  This is the only
				 * way to tell in the "cm" routine that records
				 * and not tape OBJECTS or tape MARKS are to be
				 * skipped.  The previous driver moved tape
				 * objects; not true records.
				 */
				up->Tflags.tms_wait = 1;
				rp = (REQB *) mscp_alloc_reqb( up, NULL, tmscp_rec_states, (u_long) 0, (u_long) mtop->mt_count );
				retries = RETRY_REPOS_COUNT;
				while( up->Tflags.tms_wait  && ( --retries >= 0 ) ) {
					timeout( wakeup, ( caddr_t )rp, hz );
					( void )sleep(( caddr_t )rp, PSWP+1 );
					untimeout(wakeup, ( caddr_t )rp, hz );
				}
				Time_Check(up->Tflags.tms_wait,retries,"MTFSR 1");
				up->Tflags.tms_wait = 0;
			}
              
	                /* Check the status for the command that was issued 
			* and return fail code if the status is not success.
			* The status would not be success if a tape mark has 
			* been encountered (as an example).  Clear the 
			* associated serious exception if it has been raised.
			* Serious exception will be set if the reposition
			* record command hit a tape mark.
	                */
	                if ( up->tms_status != MSCP_ST_SUCC) {
				if (up->Tflags.tms_clserex) {
					/* Allocate a request block to
					* reposition nowhere to clear the 
					* serious exception.
					*/
					up->Tflags.tms_wait = 1;
					rp = (REQB *) mscp_alloc_reqb( up, NULL, tmscp_rpo_states, (u_long) MSCP_MD_OBJCT, (u_long) 0 );
					retries = RETRY_COUNT;
					while( up->Tflags.tms_wait  && ( --retries >= 0 ) ) {
					   timeout( wakeup, ( caddr_t )rp, hz );
					   ( void )sleep(( caddr_t )rp, PSWP+1);
					   untimeout(wakeup, ( caddr_t )rp, hz);
					}
					Time_Check(up->Tflags.tms_wait,retries,"MTFSR 2");
					up->Tflags.tms_wait = 0;
				}
	              		return(EIO);
			}
			else
				return(0);

		case MTBSR: 	/* Reposition command backward count 
			 	 */
			Dprint4("MTBSR\n");
			/* Check to make sure that the unit 
			* is online.
			*/
			if( up->flags.online ) {

				/* Allocate a request block and start the data 
				 * transfer.
				 * To setup the reposition command to move
				 * RECORDS call the tmscp_rec_states instead
				 * of the tmscp_rpo_states.  This is the only
				 * way to tell in the "cm" routine that records
				 * and not tape OBJECTS or tape MARKS are to be
				 * skipped.  The previous driver moved tape
				 * object