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let ht.h define NHT
[unix-history] / usr / src / sys / vax / mba / ht.c
/* ht.c 4.2 %G% */
#include "../conf/ht.h"
#if NHT > 0
/*
* TJU16 tape driver
*/
#include "../h/param.h"
#include "../h/systm.h"
#include "../h/buf.h"
#include "../h/conf.h"
#include "../h/dir.h"
#include "../h/file.h"
#include "../h/user.h"
#include "../h/map.h"
#include "../h/pte.h"
#include "../h/mba.h"
struct device
{
int htcs1;
int htds;
int hter;
int htmr;
int htas;
int htfc;
int htdt;
int htck;
int htsn;
int httc;
};
struct buf httab;
struct buf rhtbuf;
struct buf chtbuf;
#define INF 1000000
char h_openf[NHT];
daddr_t h_blkno[NHT];
char h_flags[NHT];
daddr_t h_nxrec[NHT];
#define GO 01
#define WCOM 060
#define RCOM 070
#define NOP 0
#define WEOF 026
#define SFORW 030
#define SREV 032
#define ERASE 024
#define REW 06
#define DCLR 010
#define P800 01700 /* 800 + pdp11 mode */
#define P1600 02300 /* 1600 + pdp11 mode */
#define IENABLE 0100
#define RDY 0200
#define TM 04
#define DRY 0200
#define EOT 02000
#define CS 02000
#define COR 0100000
#define PES 040
#define WRL 04000
#define MOL 010000
#define ERR 040000
#define FCE 01000
#define TRE 040000
#define HARD 064023 /* UNS|OPI|NEF|FMT|RMR|ILR|ILF */
#define SIO 1
#define SSFOR 2
#define SSREV 3
#define SRETRY 4
#define SCOM 5
#define SOK 6
#define H_WRITTEN 1
htopen(dev, flag)
{
register unit, ds;
if ((mbaact&(1<<HTMBANUM)) == 0)
mbainit(HTMBANUM);
httab.b_flags |= B_TAPE;
unit = minor(dev) & 03;
if (unit >= NHT || h_openf[unit]) {
u.u_error = ENXIO;
return;
}
h_blkno[unit] = 0;
h_nxrec[unit] = INF;
h_flags[unit] = 0;
ds = hcommand(dev, NOP);
if ((ds&MOL)==0 || (flag && (ds&WRL)))
u.u_error = ENXIO;
if (u.u_error==0)
h_openf[unit]++;
}
htclose(dev, flag)
{
register int unit;
unit = minor(dev) & 03;
if (flag == FWRITE || ((flag&FWRITE) && (h_flags[unit]&H_WRITTEN))) {
(void) hcommand(dev, WEOF);
(void) hcommand(dev, WEOF);
(void) hcommand(dev, SREV);
}
if((minor(dev)&4) == 0) /* no 4 -> rewind */
(void) hcommand(dev, REW);
h_openf[unit] = 0;
}
hcommand(dev, com)
{
register struct buf *bp;
bp = &chtbuf;
(void) spl5();
while(bp->b_flags&B_BUSY) {
bp->b_flags |= B_WANTED;
sleep((caddr_t)bp, PRIBIO);
}
(void) spl0();
bp->b_dev = dev;
bp->b_resid = com;
bp->b_blkno = 0;
bp->b_flags = B_BUSY|B_READ;
htstrategy(bp);
iowait(bp);
if(bp->b_flags&B_WANTED)
wakeup((caddr_t)bp);
bp->b_flags = 0;
return(bp->b_resid);
}
htstrategy(bp)
register struct buf *bp;
{
register daddr_t *p;
if(bp != &chtbuf) {
p = &h_nxrec[minor(bp->b_dev)&03];
if(dbtofsb(bp->b_blkno) > *p) {
bp->b_flags |= B_ERROR;
bp->b_error = ENXIO;
iodone(bp);
return;
}
if(dbtofsb(bp->b_blkno) == *p && bp->b_flags&B_READ) {
bp->b_resid = bp->b_bcount;
clrbuf(bp);
iodone(bp);
return;
}
if ((bp->b_flags&B_READ)==0) {
*p = dbtofsb(bp->b_blkno) + 1;
h_flags[minor(bp->b_dev)&03] |= H_WRITTEN;
}
}
bp->av_forw = NULL;
(void) spl5();
if (httab.b_actf == NULL)
httab.b_actf = bp;
else
httab.b_actl->av_forw = bp;
httab.b_actl = bp;
if (httab.b_active==0)
htstart();
(void) spl0();
}
htstart()
{
register struct buf *bp;
register unit, den;
daddr_t blkno;
register struct device *htp = mbadev(HTMBA,0);
loop:
if ((bp = httab.b_actf) == NULL)
return;
unit = minor(bp->b_dev);
den = P800 | (unit&03);
if(unit >= 8)
den = P1600 | (unit&03);
if((htp->httc&03777) != den)
htp->httc = den;
unit &= 03;
blkno = h_blkno[unit];
if (bp == &chtbuf) {
if (bp->b_resid==NOP) {
bp->b_resid = htp->htds & 0xffff;
goto next;
}
httab.b_active = SCOM;
htp->htfc = 0;
htp->htcs1 = bp->b_resid|GO;
return;
}
if (h_openf[unit] < 0 || dbtofsb(bp->b_blkno) > h_nxrec[unit])
goto abort;
if (blkno == dbtofsb(bp->b_blkno)) {
httab.b_active = SIO;
htp->htfc = -bp->b_bcount;
mbastart(bp, (int *)htp);
} else {
if (blkno < dbtofsb(bp->b_blkno)) {
httab.b_active = SSFOR;
htp->htfc = blkno - dbtofsb(bp->b_blkno);
htp->htcs1 = SFORW|GO;
} else {
httab.b_active = SSREV;
htp->htfc = dbtofsb(bp->b_blkno) - blkno;
htp->htcs1 = SREV|GO;
}
}
return;
abort:
bp->b_flags |= B_ERROR;
next:
httab.b_actf = bp->av_forw;
iodone(bp);
goto loop;
}
/*ARGSUSED*/
htintr(mbastat, as)
{
register struct buf *bp;
register int unit, state;
int err;
register struct device *htp = mbadev(HTMBA,0);
if ((bp = httab.b_actf)==NULL)
return;
unit = minor(bp->b_dev) & 03;
state = httab.b_active;
httab.b_active = 0;
if (htp->htds&(ERR|EOT|TM) || mbastat & MBAEBITS) {
err = htp->hter & 0xffff;
if ((mbastat & MBAEBITS) || (err&HARD))
state = 0;
if (bp == &rhtbuf)
err &= ~FCE;
if ((bp->b_flags&B_READ) && (htp->htds&PES))
err &= ~(CS|COR);
if(htp->htds&EOT || (htp->htds&MOL)==0) {
if(h_openf[unit])
h_openf[unit] = -1;
}
else if(htp->htds&TM) {
htp->htfc = 0;
h_nxrec[unit] = dbtofsb(bp->b_blkno);
state = SOK;
}
else if(state && err == 0)
state = SOK;
if(httab.b_errcnt > 4)
deverror(bp, htp->hter, mbastat);
HTMBA->mba_cr &= ~MBAIE;
htp->htcs1 = DCLR|GO;
HTMBA->mba_cr |= MBAIE;
if (state==SIO && ++httab.b_errcnt < 10) {
httab.b_active = SRETRY;
h_blkno[unit]++;
htp->htfc = -1;
htp->htcs1 = SREV|GO;
return;
}
if (state!=SOK) {
bp->b_flags |= B_ERROR;
state = SIO;
}
} else if (htp->htcs1 < 0) { /* SC */
if(htp->htds & ERR) {
HTMBA->mba_cr &= ~MBAIE;
htp->htcs1 = DCLR|GO;
HTMBA->mba_cr |= MBAIE;
}
}
switch(state) {
case SIO:
case SOK:
h_blkno[unit]++;
case SCOM:
httab.b_errcnt = 0;
httab.b_actf = bp->av_forw;
bp->b_resid = - (htp->htfc & 0xffff);
if (bp->b_flags & B_READ)
bp->b_resid += bp->b_bcount;
iodone(bp);
break;
case SRETRY:
if((bp->b_flags&B_READ)==0) {
httab.b_active = SSFOR;
htp->htcs1 = ERASE|GO;
return;
}
case SSFOR:
case SSREV:
#define blk dbtofsb(bp->b_blkno)
if(htp->htds & TM) {
if(state == SSREV) {
h_nxrec[unit] = blk - (htp->htfc&0xffff);
h_blkno[unit] = h_nxrec[unit];
} else {
h_nxrec[unit] = blk + (htp->htfc&0xffff) - 1;
h_blkno[unit] = blk + (htp->htfc & 0xffff);
}
} else
h_blkno[unit] = blk;
break;
default:
return;
}
htstart();
}
htread(dev)
{
htphys(dev);
physio(htstrategy, &rhtbuf, dev, B_READ, minphys);
}
htwrite(dev)
{
htphys(dev);
physio(htstrategy, &rhtbuf, dev, B_WRITE, minphys);
}
htphys(dev)
{
register unit;
daddr_t a;
unit = minor(dev) & 03;
if(unit < NHT) {
a = u.u_offset >> 9;
h_blkno[unit] = dbtofsb(a);
h_nxrec[unit] = dbtofsb(a)+1;
}
}
#endif
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.