cy.c

早期freebsd实现

/*
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Computer Consoles Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *
 *	@(#)cy.c	7.8 (Berkeley) 5/8/91
 */

#include "yc.h"
#if NCY > 0
/*
 * Cipher Tapemaster driver.
 */
#define CYDEBUG
#ifdef	CYDEBUG
int	cydebug = 0;
#define	dlog(params)	if (cydebug) log params
#else
#define dlog(params)	/* */
#endif

#include "sys/param.h"
#include "sys/systm.h"
#include "sys/vm.h"
#include "sys/buf.h"
#include "sys/file.h"
#include "sys/signal.h"
#include "sys/ioctl.h"
#include "sys/mtio.h"
#include "sys/errno.h"
#include "sys/cmap.h"
#include "sys/time.h"
#include "sys/kernel.h"
#include "sys/syslog.h"
#include "sys/tprintf.h"

#include "../include/cpu.h"
#include "../include/mtpr.h"
#include "../include/pte.h"

#include "../vba/vbavar.h"
#define	CYERROR
#include "../vba/cyreg.h"

/*
 * There is a ccybuf per tape controller.
 * It is used as the token to pass to the internal routines
 * to execute tape ioctls, and also acts as a lock on the slaves
 * on the controller, since there is only one per controller.
 * In particular, when the tape is rewinding on close we release
 * the user process but any further attempts to use the tape drive
 * before the rewind completes will hang waiting for ccybuf.
 */
struct	buf ccybuf[NCY];

int	cyprobe(), cyslave(), cyattach();
struct	buf ycutab[NYC];
short	yctocy[NYC];
struct	vba_ctlr *cyminfo[NCY];
struct	vba_device *ycdinfo[NYC];
long	cystd[] = { 0 };
struct	vba_driver cydriver =
   { cyprobe, cyslave, cyattach, 0, cystd, "yc", ycdinfo, "cy", cyminfo };

/* bits in minor device */
#define	YCUNIT(dev)	(minor(dev)&03)
#define	CYUNIT(dev)	(yctocy[YCUNIT(dev)])
#define	T_NOREWIND	0x04
#define	T_1600BPI	0x00		/* pseudo */
#define	T_3200BPI	0x08		/* unused */

#define	INF	1000000L		/* close to infinity */

/*
 * Software state and shared command areas per controller.
 *
 * The i/o intermediate buffer must be allocated in startup()
 * so its address will fit in 20-bits (YECH!!!!!!!!!!!!!!).
 */
struct cy_softc {
	int	cy_bs;		/* controller's buffer size */
	struct	cyscp *cy_scp;	/* system configuration block address */
	struct	cyccb cy_ccb;	/* channel control block */
	struct	cyscb cy_scb;	/* system configuration block */
	struct	cytpb cy_tpb;	/* tape parameter block */
	struct	cytpb cy_nop;	/* nop parameter block for cyintr */
	struct	vb_buf cy_rbuf;	/* vba resources */
} cy_softc[NCY];

/*
 * Software state per tape transport.
 */
struct	yc_softc {
	char	yc_openf;	/* lock against multiple opens */
	char	yc_lastiow;	/* last operation was a write */
	short	yc_tact;	/* timeout is active */
	long	yc_timo;	/* time until timeout expires */
	u_short	yc_control;	/* copy of last tpcb.tpcontrol */
	u_short	yc_status;	/* copy of last tpcb.tpstatus */
	u_short	yc_resid;	/* copy of last bc */
	u_short	yc_dens;	/* prototype control word with density info */
	tpr_t	yc_tpr;		/* handle for tprintf */
	daddr_t	yc_blkno;	/* block number, for block device tape */
	daddr_t	yc_nxrec;	/* position of end of tape, if known */
	int	yc_blksize;	/* current tape blocksize estimate */
	int	yc_blks;	/* number of I/O operations since open */
	int	yc_softerrs;	/* number of soft I/O errors since open */
} yc_softc[NYC];

/*
 * States for vm->um_tab.b_active, the per controller state flag.
 * This is used to sequence control in the driver.
 */
#define	SSEEK	1		/* seeking */
#define	SIO	2		/* doing seq i/o */
#define	SCOM	3		/* sending control command */
#define	SREW	4		/* sending a rewind */
#define	SERASE	5		/* erase inter-record gap */
#define	SERASED	6		/* erased inter-record gap */

/* there's no way to figure these out dynamically? -- yech */
struct	cyscp *cyscp[] =
    { (struct cyscp *)0xc0000c06, (struct cyscp *)0xc0000c16 };
#define	NCYSCP	(sizeof (cyscp) / sizeof (cyscp[0]))

cyprobe(reg, vm)
	caddr_t reg;
	struct vba_ctlr *vm;
{
	register br, cvec;			/* must be r12, r11 */
	register struct cy_softc *cy;
	int ctlr = vm->um_ctlr;

#ifdef lint
	br = 0; cvec = br; br = cvec;
	cyintr(0);
#endif
	if (badcyaddr(reg+1))
		return (0);
	if (ctlr > NCYSCP || cyscp[ctlr] == 0)		/* XXX */
		return (0);
	cy = &cy_softc[ctlr];
	cy->cy_scp = cyscp[ctlr];			/* XXX */
	/*
	 * Tapemaster controller must have interrupt handler
	 * disable interrupt, so we'll just kludge things
	 * (stupid multibus non-vectored interrupt crud).
	 */
	if (cyinit(ctlr, reg)) {
		uncache(&cy->cy_tpb.tpcount);
		cy->cy_bs = htoms(cy->cy_tpb.tpcount);
		/*
		 * Setup nop parameter block for clearing interrupts.
		 */
		cy->cy_nop.tpcmd = CY_NOP;
		cy->cy_nop.tpcontrol = 0;
		/*
		 * Allocate page tables.
		 */
		if (cybuf == 0) {
			printf("no cy buffer!!!\n");
			return (0);
		}
		cy->cy_rbuf.vb_rawbuf = cybuf + ctlr * CYMAXIO;
		if (vbainit(&cy->cy_rbuf, CYMAXIO, VB_20BIT) == 0) {
			printf("cy%d: vbainit failed\n", ctlr);
			return (0);
		}

		br = 0x13, cvec = 0x80;			/* XXX */
		return (sizeof (struct cyccb));
	} else
		return (0);
}

/*
 * Check to see if a drive is attached to a controller.
 * Since we can only tell that a drive is there if a tape is loaded and
 * the drive is placed online, we always indicate the slave is present.
 */
cyslave(vi, addr)
	struct vba_device *vi;
	caddr_t addr;
{

#ifdef lint
	vi = vi; addr = addr;
#endif
	return (1);
}

cyattach(vi)
	struct vba_device *vi;
{
	register struct cy_softc *cy;
	int ctlr = vi->ui_mi->um_ctlr;

	yctocy[vi->ui_unit] = ctlr;
	cy = &cy_softc[ctlr];
	if (vi->ui_slave == 0 && cy->cy_bs)
		printf("; %dkb buffer", cy->cy_bs/1024);
}

/*
 * Initialize the controller after a controller reset or
 * during autoconfigure.  All of the system control blocks
 * are initialized and the controller is asked to configure
 * itself for later use.
 */
cyinit(ctlr, addr)
	int ctlr;
	register caddr_t addr;
{
	register struct cy_softc *cy = &cy_softc[ctlr];
	register int *pte;

	/*
	 * Initialize the system configuration pointer.
	 */
	/* make kernel writable */
	pte = (int *)&Sysmap[btop((int)cy->cy_scp &~ KERNBASE)]; 
	*pte &= ~PG_PROT; *pte |= PG_KW;
	mtpr(TBIS, cy->cy_scp);
	/* load the correct values in the scp */
	cy->cy_scp->csp_buswidth = CSP_16BITS;
	cyldmba(cy->cy_scp->csp_scb, (caddr_t)&cy->cy_scb);
	/* put it back to read-only */
	*pte &= ~PG_PROT; *pte |= PG_KR;
	mtpr(TBIS, cy->cy_scp);

	/*
	 * Init system configuration block.
	 */
	cy->cy_scb.csb_fixed = CSB_FIXED;
	/* set pointer to the channel control block */
	cyldmba(cy->cy_scb.csb_ccb, (caddr_t)&cy->cy_ccb);

	/*
	 * Initialize the chanel control block.
	 */
	cy->cy_ccb.cbcw = CBCW_CLRINT;
	cy->cy_ccb.cbgate = GATE_OPEN;
	/* set pointer to the tape parameter block */
	cyldmba(cy->cy_ccb.cbtpb, (caddr_t)&cy->cy_tpb);

	/*
	 * Issue a nop cmd and get the internal buffer size for buffered i/o.
	 */
	cy->cy_tpb.tpcmd = CY_NOP;
	cy->cy_tpb.tpcontrol = CYCW_16BITS;
	cy->cy_ccb.cbgate = GATE_CLOSED;	
	CY_GO(addr);
	if (cywait(&cy->cy_ccb) || (cy->cy_tpb.tpstatus&CYS_ERR)) {
		uncache(&cy->cy_tpb.tpstatus);
		printf("cy%d: timeout or err during init, status=%b\n", ctlr,
		    cy->cy_tpb.tpstatus, CYS_BITS);
		return (0);
	}
	cy->cy_tpb.tpcmd = CY_CONFIG;
	cy->cy_tpb.tpcontrol = CYCW_16BITS;
	cy->cy_ccb.cbgate = GATE_CLOSED;	
	CY_GO(addr);
	if (cywait(&cy->cy_ccb) || (cy->cy_tpb.tpstatus&CYS_ERR)) {
		uncache(&cy->cy_tpb.tpstatus);
		printf("cy%d: configuration failure, status=%b\n", ctlr,
		    cy->cy_tpb.tpstatus, CYS_BITS);
		return (0);
	}
	return (1);
}

int	cytimer();
/*
 * Open the device.  Tapes are unique open
 * devices, so we refuse if it is already open.
 * We also check that a tape is available, and
 * don't block waiting here; if you want to wait
 * for a tape you should timeout in user code.
 */
cyopen(dev, flag)
	dev_t dev;
	register int flag;
{
	register int ycunit;
	register struct vba_device *vi;
	register struct yc_softc *yc;

	ycunit = YCUNIT(dev);
	if (ycunit >= NYC || (vi = ycdinfo[ycunit]) == 0 || vi->ui_alive == 0)
		return (ENXIO);
	if ((yc = &yc_softc[ycunit])->yc_openf)
		return (EBUSY);
	yc->yc_openf = 1;
#define	PACKUNIT(vi) \
    (((vi->ui_slave&1)<<11)|((vi->ui_slave&2)<<9)|((vi->ui_slave&4)>>2))
	/* no way to select density */
	yc->yc_dens = PACKUNIT(vi)|CYCW_IE|CYCW_16BITS;
	if (yc->yc_tact == 0) {
		yc->yc_timo = INF;
		yc->yc_tact = 1;
		timeout(cytimer, (caddr_t)dev, 5*hz);
	}
	cycommand(dev, CY_SENSE, 1);
	if ((yc->yc_status&CYS_OL) == 0) {	/* not on-line */
		uprintf("cy%d: not online\n", ycunit);
		yc->yc_openf = 0;
		return (EIO);
	}
	if ((flag&FWRITE) && (yc->yc_status&CYS_WP)) {
		uprintf("cy%d: no write ring\n", ycunit);
		yc->yc_openf = 0;
		return (EIO);
	}
	yc->yc_blkno = (daddr_t)0;
	yc->yc_nxrec = INF;
	yc->yc_lastiow = 0;
	yc->yc_blksize = CYMAXIO;		/* guess > 0 */
	yc->yc_blks = 0;
	yc->yc_softerrs = 0;
	yc->yc_tpr = tprintf_open();
	return (0);
}

/*
 * Close tape device.
 *
 * If tape was open for writing or last operation was a write,
 * then write two EOF's and backspace over the last one.
 * Unless this is a non-rewinding special file, rewind the tape.
 * Make the tape available to others.
 */
cyclose(dev, flag)
	dev_t dev;
	int flag;
{
	struct yc_softc *yc = &yc_softc[YCUNIT(dev)];

	if (flag == FWRITE || (flag&FWRITE) && yc->yc_lastiow) {
		cycommand(dev, CY_WEOF, 1);	/* can't use count with WEOF */
		cycommand(dev, CY_WEOF, 1);
		cycommand(dev, CY_SREV, 1);
	}
	if ((minor(dev)&T_NOREWIND) == 0)
		/*
		 * 0 count means don't hang waiting for rewind complete
		 * rather ccybuf stays busy until the operation completes
		 * preventing further opens from completing by preventing
		 * a CY_SENSE from completing.
		 */
		cycommand(dev, CY_REW, 0);
	if (yc->yc_blks > 10 && yc->yc_softerrs > yc->yc_blks / 10)
		log(LOG_INFO, "yc%d: %d soft errors in %d blocks\n",
		    YCUNIT(dev), yc->yc_softerrs, yc->yc_blks);
	dlog((LOG_INFO, "%d soft errors in %d blocks\n",
	    yc->yc_softerrs, yc->yc_blks));
	tprintf_close(yc->yc_tpr);
	yc->yc_openf = 0;
	return (0);
}

/*
 * Execute a command on the tape drive a specified number of times.
 */
cycommand(dev, com, count)
	dev_t dev;
	int com, count;
{
	register struct buf *bp;
	int s;
	
	bp = &ccybuf[CYUNIT(dev)];
	s = spl3();
	dlog((LOG_INFO, "cycommand(%o, %x, %d), b_flags %x\n",
	    dev, com, count, bp->b_flags));
	while (bp->b_flags&B_BUSY) {
		/*