scsi_tape.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef lint
static	char	*sccsid = "@(#)scsi_tape.c	4.6  (ULTRIX)        1/22/91";
#endif lint

/************************************************************************
 *									*
 *			Copyright (c) 1984,86,87,88,89 by		*
 *		Digital Equipment Corporation, Maynard, MA		*
 *			All rights reserved.				*
 *									*
 *   This software is furnished under a license and may be used and	*
 *   copied  only  in accordance with the terms of such license and	*
 *   with the  inclusion  of  the  above  copyright  notice.   This	*
 *   software  or  any	other copies thereof may not be provided or	*
 *   otherwise made available to any other person.  No title to and	*
 *   ownership of the software is hereby transferred.			*
 *									*
 *   This software is  derived	from  software	received  from	the	*
 *   University    of	California,   Berkeley,   and	from   Bell	*
 *   Laboratories.  Use, duplication, or disclosure is	subject  to	*
 *   restrictions  under  license  agreements  with  University  of	*
 *   California and with AT&T.						*
 *									*
 *   The information in this software is subject to change  without	*
 *   notice  and should not be construed as a commitment by Digital	*
 *   Equipment Corporation.						*
 *									*
 *   Digital assumes no responsibility for the use  or	reliability	*
 *   of its software on equipment which is not supplied by Digital.	*
 *									*
 ************************************************************************/

/************************************************************************
 *
 * scsi_tape.c	23_Jun-89
 *
 * VAX SCSI device driver (tape routines)
 *
 * Modification history:
 *
 *  08-Jan-91	Robin Miller
 *	Modified DEVIOCGET ioctl() code to properly return tape density
 *	codes.  To resolve this problem, the density_table[] was defined
 *	to decode the mode sense density code, and additional code was
 *	added to return default density codes.
 *
 *  15-Nov-90	Robin Miller
 *	Removed clearing of the DEV_TPMARK flag in tzstrategy() for nbuf
 *	I/O requests (B_RAWASYNC).  This caused a race condition with code
 *	in the SCSI state machine with outstanding read requests.  This
 *	problem caused the queued reads to read past the tape file mark.
 *
 *  21-Sept-90	Bill Dallas
 *	Fixed 2 problems with the devget ioctl.
 *	Problem one caused a panic if someone made a minor
 *	number by hand (aka mknod) which was out side the
 *	controllers range. The second problem was minor,
 *	we never gave back to the user the lower 4 bits
 *	of the devget.category_stat field.
 *
 *  30-Jul-90	Bill Dallas   
 *	Added fixed block tape units tape mark handling.
 *	This included a new falg in sc_category_flags called
 *	TPMARK_PENDING
 *
 *  13-Nov-89   Janet Schank
 *      Changed the refrence of nNSCSI to nNSCSIBUS.
 *
 *  08-Oct-89	Fred Canter
 *	Bump TZ30 minium revision level to 11. It should be 12, but
 *	we never received rev 12 drives to test.
 *	Remove #ifdef OLDWAY.
 *
 *  01-Oct-89	Fred Canter
 *	Bug fix. Tapes were not reporting write locked status via the
 *	devioget ioctl.
 *
 *  24-Jul-89	Fred Canter
 *	Bug fix for dump (MT CACHE ioctls not supported by SCSI).
 *
 *  16-Jul-89	Fred Canter
 *	Changed meaning of count field for MODSNS tzcommand/rzcommand.
 *
 *  23-Jun-89	John A. Gallant
 *	Added the tape command completion routine.
 *
 *  19-Jun-89	Fred Canter
 *	Convert to scsi_devtab.
 *
 * 13-Jun-89	Fred Canter
 *	Added MTFLUSH to tzioctl (always returns ENXIO).
 *
 * 06-Apr-89	Fred Canter
 *	Added TZxx (EXABYTE) support. Cannot count on TZxx drives
 *	supporting the receive diagnostic results command.
 *
 *	Added b_comand to replace b_command for local command buffers.
 *	Use b_gid instead of b_resid to store command.
 *
 *	Added debug code to allow mode sense before tape open.
 *
 * 12-Feb-89	Fred Canter
 *	Added function header comments to each routine.
 *
 *  5-Feb-89	Fred Canter
 *	Added tz_tz30_minrev and tz_tzk50_minrev so minimum firmware
 *	revision levels for tapes can be changed with adb.
 *
 * 14-Jan-89	Fred Canter
 *	Clear sc_category_flags in tzopen() so left over DEV_TPMARK
 *	does not casue drive to fail all commands after encountering
 *	a tape mark.
 *	Fixed a bug which caused a space command (via ioctl) to
 *	space over a tape mark without failing (as it should).
 *	In tzioctl(), fail the ioctl if DEV_TPMARK set.
 *	Update minimum firmware revision for the TZK50 to 45.
 *
 * 28-Dec-88	Fred Canter
 *	Changed stops to tzops in tzioctl, for consistency.
 *
 * 18-Dec-88	Fred Canter
 *	Fixed (as best I could) info returned for MTIOCGET ioctl
 *	(mt status). So MTX can handle EOT on SCSI tapes.
 *
 * 17-Dec-88	Fred Canter
 *	Added pseudo commands to resolve the conflict between
 *	SZ_UNLOAD and SZ_SSUNIT both being opcode 0x1b.
 *
 * 16-Oct-88	Fred Canter
 *	Clean up comments.
 *
 * 28-Sep-88	Fred Canter
 *	Clean up comments.
 *
 * 21-Aug-88	Fred Canter
 *	Fixed a bug which caused the magtape exerciser MTIOCTOP ioctl
 *	to fail. Check status and sense key after ioctl.
 *
 * 17-Aug-88	Fred Canter
 *	Created this file by moving the SCSI tape specific files
 *	from the old combined driver (scsi.c) to scsi_tape.c.
 *
 ***********************************************************************/

#include "scsi.h"
#include "sii.h"

#if NSCSI > 0 || NSII > 0 || defined(BINARY)

#include "../data/scsi_data.c"
#include "scsi_debug.h"

/*
 * Define the tape density table.
 */
static int density_table[] = {
	0,				/* 0x00 - Default density.	*/
	DEV_800BPI,			/* 0x01 - 800 BPI   (NRZI, R)	*/
	DEV_1600BPI,			/* 0x02 - 1600 BPI  (PE, R)	*/
	DEV_6250BPI,			/* 0x03 - 6250 BPI  (GCR, R)	*/
	DEV_8000_BPI,			/* 0x04 - 8000 BPI  (GCR, C)	*/
	DEV_8000_BPI,			/* 0x05 - 8000 BPI  (GCR, C)	*/
	0,				/* 0x06 - 3200 BPI  (PE, R)	*/
	0,				/* 0x07 - 6400 BPI  (IMFM, C)	*/
	DEV_8000_BPI,			/* 0x08 - 8000 BPI  (GCR, CS)	*/
	DEV_38000BPI,			/* 0x09 - 37871 BPI (GCR, C)	*/
	DEV_6666BPI,			/* 0x0A - 6667 BPI  (MFM, C)	*/
	DEV_1600BPI,			/* 0x0B - 1600 BPI  (PE, C)	*/
	0,				/* 0x0C - 12690 BPI (GCR, C)	*/
	DEV_10000_BPI,			/* 0x0D - QIC-120 with ECC.	*/
	DEV_10000_BPI,			/* 0x0E - QIC-150 with ECC.	*/
	DEV_10000_BPI,			/* 0x0F - QIC-120   (GCR, C)	*/
	DEV_10000_BPI,			/* 0x10 - QIC-150   (GCR, C)	*/
	DEV_16000_BPI,			/* 0x11 - QIC-320   (GCR, C)	*/
	0,				/* 0x12 - QIC-1350  (RLL, C)	*/
	DEV_61000_BPI,			/* 0x13 - 4mm Tape  (DDS, CS)	*/
	DEV_54000_BPI			/* 0x14 - 8mm Tape  (???, CS)	*/
};
static int density_entrys = sizeof(density_table) / sizeof(int);

/*
 * TODO:
 *	Temporary(?) debug variable.
 *	If nonzero, SZ_NODEVICE is returned from tz_rcvdiag()
 *	if the tape fails self test or its firmware revision
 *	level is too far out of date.
 *	If zero, tz_rcvdiag() results are ignored.
 */
int sz_open_fst = 1;

int	wakeup();
extern int hz;


extern int sz_unit_rcvdiag[];	/* If zero, need unit's selftest status */

/*
 * Unit on line flag. Set to one if the
 * device is on-line. Set to zero on any unit
 * attention condition.
 */
extern int sz_unit_online[];

/*
 *
 * Name:		tzopen		-Tape open routine
 *
 * Abstract:		This routine is called each time a tape device
 *			is opened. This routine: makes sure the device
 *			exists, checks for device on-line via test unit
 *			ready, and does a mode select (sets buffered mode).
 *			On the first call, a receive diagnostic results
 *			command is done to make sure the tape drive is ok.
 *
 * Inputs:
 *
 * dev			ULTRIX major/minor device number.
 * flag			How to open flag (read, write, NDELAY).
 *
 * Outputs:
 *			Possible error messages (eg, device off-line).
 *			sz_unit_online flag set.
 *			Exclusive use flag (sc_openf) flag set.
 *
 * Return Values:
 *
 * ENXIO		No such device or address (non extistent device).
 * EIO			I/O error (device off-line, etc).
 * 0			Open succeeded.
 *
 * Side Effects:
 *			tzcommand() called.
 *			sleep() called.
 *
 */

tzopen(dev, flag)
	register dev_t dev;
	register int flag;
{
	register struct uba_device *ui;
	register struct sz_softc *sc;
	int unit = UNIT(dev);
	int cntlr;
	int targid;
	int retry = 0;
	int retval;
	int dev_ready;
	struct sz_modsns_dt *sdp;

	/*
	 * Order of following checks is important.
	 */
	if (unit >= nNSZ)
	    return(ENXIO);
	ui = szdinfo[unit];
	if ((ui == 0) || (ui->ui_alive == 0))
	    return(ENXIO);
	cntlr = ui->ui_ctlr;
	if (cntlr >= nNSCSIBUS)
	    return(ENXIO);
	targid = ui->ui_slave;
	sc = &sz_softc[cntlr];
	if (sc->sc_alive[targid] == 0 || sc->sc_openf[targid])
	    return (ENXIO);
	if ((sc->sc_devtyp[targid] & SZ_TAPE) == 0)
	    return(ENXIO);
	/*
	 * This is a strange use of the FNDELAY flag.  It
	 * is here to allow the installation finder program
	 * to open the device when the tape cartridge is not
	 * inserted.  The installation finder program needs
	 * to do an ioctl, so open must succeed whether or
	 * not a cartridge is present.
	 */
	/*
	 * Clear sc_flags, device will lockup after any
	 * hard error (DEV_HARDERR set) if we don't.
	 * TODO: other drivers look at dis_eot_??[]!
	 */
	sc->sc_flags[targid] = 0;

	sc->sc_category_flags[targid] = 0;
	sc->sc_szflags[targid] &= ~SZ_NODEVICE;

	/*
	 * Get selftest result, if we haven't already.
	 * The tz_rcvdiag() routine will return
	 * SZ_NODEVICE if anything is wrong.
	 *
	 * Fix for the nodiag flag in devtab..Some units
	 * must have a senddiag cmd before a recvdiag cmd 
 	 * or data is garbage for the recv diag cmd. We 
	 * will just look at the NO_DIAG flag in the devtab
	 * struct for this type unit.
	 */
	if ((sz_unit_rcvdiag[unit] == 0) && 
		((sc->sc_devtab[targid]->flags & SCSI_NODIAG) == 0))
	    {
	    sc->sc_szflags[targid] |= tz_rcvdiag(dev);
	}

	/*
	 * Try to bring the drive on line.
	 * The TZK50 takes about 25 seconds come ready after
	 * a cartridge change. The TZ30 takes about 30 seconds.
	 * So, we try for 40 seconds to bring the drive on-line.
	 * This allows the user some think time to realize the
	 * tape is off-line and load the cartridge.
	 */
	dev_ready = 0;
	for (retry = 0; retry < 20; retry++) {
	    if (sc->sc_szflags[targid] & SZ_NODEVICE) {
		if (flag & FNDELAY)
		    break;
		else
		    return(ENXIO);
	    }
	    tzcommand(dev, SZ_TUR, 1, 0);
	    if (sc->sc_c_status[targid] == SZ_GOOD) {
		dev_ready = 1;
		break;
	    }
	    else if (sc->sc_c_status[targid] == SZ_BAD) {
		continue;
	    }
	    else if (sc->sc_c_status[targid] == SZ_CHKCND) {
		retval = SZ_RETRY;
		switch(sc->sc_c_snskey[targid]) {
		case SZ_NOSENSE:
		case SZ_RECOVERR:
		    retval = SZ_SUCCESS;
		    dev_ready = 1;
		    break;

		case SZ_NOTREADY:
		    timeout(wakeup, (caddr_t)&sc->sc_alive[targid], (hz*2));
		    sleep((caddr_t)&sc->sc_alive[targid], PZERO + 1);
		    if (!(sc->sc_flags[targid] & DEV_EOM)) {
			sc->sc_flags[targid] = 0;
		    }
		    break;

		case SZ_UNITATTEN:
		    sz_unit_online[unit] = 0;
		    /* just retry */
		    break;

		default:
		    /* TODO: may want to retry? */
		    if (!(sc->sc_flags[targid] & DEV_EOM)) {
			sc->sc_flags[targid] = 0;
		    }
		    if(flag & FNDELAY) {
			sc->sc_szflags[targid] |= SZ_NODEVICE;
			retval = SZ_SUCCESS;
		    }
		    else {
			return(ENXIO);
		    }
		    break;
		}	/* end of switch */
		if (retval == SZ_SUCCESS)
		    break;		/* from for loop */
		else
		    continue;		/* with for loop */
	    }
	    else {
		/* TODO: debug */
		printf("tzopen: impossible sc_c_status (val=%d)\n",
		    sc->sc_c_status[targid]);
		continue;	/* retry */
	    }
	}	/* end for loop */
	if (retry >= 20) {
	    if (!(flag & FNDELAY)) {
	    	DEV_UGH(sc->sc_device[targid], unit, "offline");
	    	return(EIO);
	    }
	}
	/*
	 * If SZ_NODEVICE is not set, the device exists,
	 * and we want to do a SZ_MODSEL command
	 */
	if (!(sc->sc_szflags[targid] & SZ_NODEVICE)) {
	    if (tz_exabyte_modsns) {
		tzcommand(dev, SZ_MODSNS, -1, 0);
		if (sc->sc_c_status[targid] != SZ_GOOD)
		    printf("tzopen: %s unit %d: mode sense failed\n",
			sc->sc_device[targid], unit);
		sdp = (struct sz_modsns_dt *)&sc->sz_dat[targid];
		printf("vu = 0x%x, mt = 0x%x, rt = 0x%x\n", sdp->vulen,
			sdp->pad[0], sdp->pad[1]);
	    }
	    for (retry = 0; retry < 5; retry++) {
		tzcommand(dev, SZ_MODSEL, 1, 0);
		if (sc->sc_c_status[targid] == SZ_GOOD)
		    break;
	    }
	    if ((retry >= 5) && ((flag & FNDELAY) == 0)) {
		printf("tzopen: %s unit %d: mode select failed\n",
		    sc->sc_device[targid], unit);
		return(EIO);
	    }
	}
	/* So open nodelay doesn't falsely set on-line! */
	if (dev_ready)
	    sz_unit_online[unit] = 1;
	sc->sc_openf[targid] = 1;
	return (0);
}



int	tz_tz30_minrev = 11;	/* Minimum TZ30 firmware revision */
int	tz_tzk50_minrev = 45;	/* Minimum TZK50 firmware revision */

/*
 *
 * Name:		tz_rcvdiag	-Receive diagnostic results
 *
 * Abstract:		This routine executes a receive diagnostic results
 *			command for the specified tape drive, and uses
 *			the results to determine if the tape exists,
 *			is up to minimum firmware revision, and passed
 *			self test.
 *
 * Inputs:
 *
 * dev			ULTRIX major/minor device number.
 *
 * Outputs:
 *			sz_unit_rcvdiag flag set.
 *			Possible firmware revision level warning message.
 *			Possible error message (receive diagnostics failed).
 *
 * Return Values:
 *
 * SZ_NODEVICE		Tape drive does not exist or failed self test.
 * SZ_SUCCESS		Tape exists and is operational.
 *