USG_PG3/usr/source/io2/rp.c

#
/*
 * RP disk driver
 */

#include "../head/param.h"
#include "../head/systm.h"
#include "../head/buf.h"
#include "../head/bufx.h"
#include "../head/conf.h"
#include "../head/user.h"
#include "../head/userx.h"
#include "../head/elog.h"

struct  rpregs {
	int	rpds;
	int	rper;
	int	rpcs;
	int	rpwc;
	int	rpba;
	int	rpca;
	int	rpda;
};

#define	RPADDR	0176710
#define	NRP	2

struct {
	char	*nblocks;
	int	cyloff;
} rp_sizes[] {
	40600L,	0,		/* cyl 0 thru 202 */
	40600L,	203,		/* cyl 203 thru 405 */
	9200,	0,		/* cyl 0 thru 45 */
	9200,	360,		/* cyl 360 thru 405 */
	65535L,	0,		/* cyl 0 thru 327 */
	65535L,	78,		/* cyl 78 thru 405 */
	15600,	0,		/* cyl 0 thru 77 */
	15600,	328,		/* cyl 328 thru 405 */
};

struct	devtab	rptab;
struct	buf	rrpbuf;

struct	iostat	rpstat[NRP];
struct	errtab	rpetab { etabinit(E_BLK,NRP,RP,rpstat) };

#define	GO	01
#define	RESET	0
#define	HSEEK	014

#define	IENABLE	0100
#define	READY	0200

#define	SUFU	01000
#define	SUSU	02000
#define	SUSI	04000
#define	HNF	010000

/*
 * Use av_back to save track+sector,
 * b_resid for cylinder.
 */

#define	trksec	av_back
#define	cylin	b_resid

/*
 * Monitoring device number
 */
#define	DK_N	2

rpopen(dev, flag)
{
	if (dev.d_minor >= (NRP<<3))
		u.u_error = ENXIO;
}

rpstrategy(abp)
struct buf *abp;
{
	register struct buf *bp;
	register char *p1, *p2;

	bp = abp;
	if(bp->b_flags&B_PHYS)
		mapalloc(bp);
	p1 = &rp_sizes[bp->b_dev.d_minor&07];
	if(bp->b_blkno >= p1->nblocks) {
		if (bp->b_flags&B_READ)
			bp->b_resid = bp->b_wcount;
		else {
			bp->b_flags =| B_ERROR;
			bp->b_error = ENXIO;
		}
		iodone(bp);
		return;
	}
	bp->av_forw = 0;
	bp->cylin = p1->cyloff;
	p1 = bp->b_blkno;
	p2 = lrem(p1, 10);
	p1 = ldiv(p1, 10);
	bp->trksec = (p1%20)<<8 | p2;
	bp->cylin =+ p1/20;
	spl5();
	if ((p1 = rptab.d_actf)==0)
		rptab.d_actf = bp;
	else {
		for (; p2 = p1->av_forw; p1 = p2) {
			if (p1->cylin <= bp->cylin
			 && bp->cylin <  p2->cylin
			 || p1->cylin >= bp->cylin
			 && bp->cylin >  p2->cylin) 
				break;
		}
		bp->av_forw = p2;
		p1->av_forw = bp;
	}
	if (rptab.d_active==0)
		rpstart();
	spl0();
}

rpstart()
{
	register struct buf *bp;
	register int n;

	if ((bp = rptab.d_actf) == 0)
		return;
	rptab.d_active++;
	n = bp->b_dev.d_minor>>3;
	rpetab.e_aunit = &rpstat[n];
	rpetab.e_aunit->io_ops++;
	blkacty =| (1<<RP);
	RPADDR->rpda = bp->trksec;
	devstart(bp, &RPADDR->rpca, bp->cylin, n);
	dk_busy =| 1<<DK_N;
	dk_numb[DK_N] =+ 1;
	dk_wds[DK_N] =+ (-bp->b_wcount>>5) & 03777;
}

rpintr()
{
	register struct buf *bp;
	register int ctr;
	struct rpregs rpregs[0];

	if (rptab.d_active == 0)
		return;
	blkacty =& ~(1<<RP);
	dk_busy =& ~(1<<DK_N);
	bp = rptab.d_actf;
	rptab.d_active = 0;
	if (RPADDR->rpcs < 0) {		/* error bit */
/*		deverror(bp, RPADDR->rper, RPADDR->rpds);  /**/
		fmtblk(&rpetab,RPADDR,sizeof(rpregs[0])/2,bp);
		if(RPADDR->rpds & (SUFU|SUSI|HNF)) {
			RPADDR->rpcs.lobyte = HSEEK|GO;
			rpetab.e_aunit->io_misc++;
			ctr = 0;
			while ((RPADDR->rpds&SUSU) && --ctr);
		}
		RPADDR->rpcs = RESET|GO;
		rpetab.e_aunit->io_misc++;
		ctr = 0;
		while ((RPADDR->rpcs&READY) == 0 && --ctr);
		if (rptab.d_errcnt < 10) {
			if(rptab.d_errcnt++ == 0)
				logerr(&rpetab,E_FIRST);
			rpstart();
			return;
		}
		bp->b_flags =| B_ERROR;
	}
	if(rpetab.e_emsg != NULL)
		logerr(&rpetab,E_RETRY);
	rptab.d_errcnt = 0;
	rptab.d_actf = bp->av_forw;
	bp->b_resid = RPADDR->rpwc;
	iodone(bp);
	rpstart();
}

rpread(dev)
{
	register nblks;

	nblks = rp_sizes[dev.d_minor & 07].nblocks;
	physio(rpstrategy, &rrpbuf, dev, B_READ, nblks);
}

rpwrite(dev)
{
	register nblks;

	nblks = rp_sizes[dev.d_minor & 07].nblocks;
	physio(rpstrategy, &rrpbuf, dev, B_WRITE, nblks);
}