[unix-history] / usr / src / sys / vax / uba / tm.c

/*	tm.c	4.5	%G%	*/

#include "tm.h"
#if NTM > 0
/*
 * TM tape driver
 */

#include "../h/param.h"
#include "../h/buf.h"
#include "../h/dir.h"
#include "../h/conf.h"
#include "../h/user.h"
#include "../h/file.h"
#include "../h/map.h"
#include "../h/pte.h"
#include "../h/uba.h"
#include "../h/mtio.h"
#include "../h/ioctl.h"
#include "../h/vm.h"

struct device {
	u_short	tmer;
	u_short	tmcs;
	short	tmbc;
	u_short tmba;
	short	tmdb;
	short	tmrd;
};

#define	b_repcnt  b_bcount
#define	b_command b_resid

struct	buf	tmtab;
struct	buf	ctmbuf;
struct	buf	rtmbuf;

int	tm_ubinfo;

/* bits in minor device */
#define	T_NOREWIND	04
#define	T_1600BPI	08

#define	INF	(daddr_t)1000000L

/*
 * Really only handle one tape drive... if you have more than one,
 * you can make all these arrays and change the obvious things, but
 * it is not clear what happens when some drives are transferring while
 * others rewind, so we don't pretend that this driver handles multiple
 * tape drives.
 */
char	t_openf;
daddr_t	t_blkno;
char	t_flags;
daddr_t	t_nxrec;
u_short	t_erreg;
u_short	t_dsreg;
short	t_resid;

/* bits in tmcs */
#define	GO	01
#define	OFFL	0
#define	RCOM	02
#define	WCOM	04
#define	WEOF	06
#define	SFORW	010
#define	SREV	012
#define	WIRG	014
#define	REW	016
#define	IENABLE	0100
#define	CUR	0200
#define	NOP	IENABLE
#define	DCLR	010000
#define	D800	060000
#define	ERROR	0100000

/* bits in tmer */
#define	TUR	1
#define	RWS	02
#define	WRL	04
#define	SDWN	010
#define	BOT	040
#define	SELR	0100
#define	NXM	0200
#define	TMBTE	0400
#define	RLE	01000
#define	EOT	02000
#define	BGL	04000
#define	PAE	010000
#define	CRE	020000
#define	EOF	040000
#define	ILC	0100000

#define	HARD    (ILC|EOT)
#define	SOFT	(CRE|PAE|BGL|RLE|TMBTE|NXM)

#define	SSEEK	1		/* seeking */
#define	SIO	2		/* doing seq i/o */
#define	SCOM	3		/* sending control command */

#define	LASTIOW 1		/* last op was a write */
#define	WAITREW	2		/* someone is waiting for a rewind */

tmopen(dev, flag)
	dev_t dev;
	int flag;
{
	register ds, unit;

	tmtab.b_flags |= B_TAPE;
	unit = minor(dev)&03;
	if (unit >= NTM || t_openf) {
		u.u_error = ENXIO;		/* out of range or open */
		return;
	}
	tcommand(dev, NOP, 1);
	if ((t_erreg&SELR) == 0) {
		u.u_error = EIO;		/* offline */
		return;
	}
	t_openf = 1;
	if (t_erreg&RWS)
		tmwaitrws(dev);			/* wait for rewind complete */
	while (t_erreg&SDWN)
		tcommand(dev, NOP, 1);		/* await settle down */
	if ((t_erreg&TUR)==0 ||
	    ((flag&(FREAD|FWRITE)) == FWRITE && (t_erreg&WRL))) {
		TMADDR->tmcs = DCLR|GO;
		u.u_error = EIO;		/* offline or write protect */
	}
	if (u.u_error != 0) {
		t_openf = 0;
		return;
	}
	t_blkno = (daddr_t)0;
	t_nxrec = INF;
	t_flags = 0;
	t_openf = 1;
}

tmwaitrws(dev)
	register dev;
{

	spl5();
	for (;;) {
		if ((TMADDR->tmer&RWS) == 0) {
			spl0();		/* rewind complete */
			return;
		}
		t_flags |= WAITREW;
		sleep((caddr_t)&t_flags, PRIBIO);
	}
}

tmclose(dev, flag)
	register dev_t dev;
	register flag;
{

	if (flag == FWRITE || ((flag&FWRITE) && (t_flags&LASTIOW))) {
		tcommand(dev, WEOF, 1);
		tcommand(dev, WEOF, 1);
		tcommand(dev, SREV, 1);
	}
	if ((minor(dev)&T_NOREWIND) == 0)
		tcommand(dev, REW, 1);
	t_openf = 0;
}

tcommand(dev, com, count)
	dev_t dev;
	int com, count;
{
	register struct buf *bp;

	bp = &ctmbuf;
	(void) spl5();
	while (bp->b_flags&B_BUSY) {
		bp->b_flags |= B_WANTED;
		sleep((caddr_t)bp, PRIBIO);
	}
	bp->b_flags = B_BUSY|B_READ;
	(void) spl0();
	bp->b_dev = dev;
	bp->b_repcnt = -count;
	bp->b_command = com;
	bp->b_blkno = 0;
	tmstrategy(bp);
	iowait(bp);
	if (bp->b_flags&B_WANTED)
		wakeup((caddr_t)bp);
	bp->b_flags &= B_ERROR;
}

tmstrategy(bp)
	register struct buf *bp;
{
	register daddr_t *p;

	tmwaitrws(bp->b_dev);
	if (bp != &ctmbuf) {
		p = &t_nxrec;
		if (dbtofsb(bp->b_blkno) > *p) {
			bp->b_flags |= B_ERROR;
			bp->b_error = ENXIO;		/* past EOF */
			iodone(bp);
			return;
		} else if (dbtofsb(bp->b_blkno) == *p && bp->b_flags&B_READ) {
			bp->b_resid = bp->b_bcount;
			clrbuf(bp);			/* at EOF */
			iodone(bp);
			return;
		} else if ((bp->b_flags&B_READ) == 0)
			*p = dbtofsb(bp->b_blkno) + 1;	/* write sets EOF */
	}
	bp->av_forw = NULL;
	(void) spl5();
	if (tmtab.b_actf == NULL)
		tmtab.b_actf = bp;
	else
		tmtab.b_actl->av_forw = bp;
	tmtab.b_actl = bp;
	if (tmtab.b_active == 0)
		tmstart();
	(void) spl0();
}

tmstart()
{
	register struct buf *bp;
	register cmd;
	register daddr_t blkno;
	int s;

loop:
	if ((bp = tmtab.b_actf) == 0)
		return;
	t_dsreg = TMADDR->tmcs;
	t_erreg = TMADDR->tmer;
	t_resid = TMADDR->tmbc;
	t_flags &= ~LASTIOW;
	if (t_openf < 0 || (TMADDR->tmcs&CUR) == 0) {
		/* t_openf = -1; ??? */
		bp->b_flags |= B_ERROR;		/* hard error'ed or !SELR */
		goto next;
	}
	cmd = IENABLE | GO;
	if ((minor(bp->b_dev) & T_1600BPI) == 0)
		cmd |= D800;
	if (bp == &ctmbuf) {
		if (bp->b_command == NOP)
			goto next;		/* just get status */
		else {
			cmd |= bp->b_command;
			tmtab.b_active = SCOM;
			if (bp->b_command == SFORW || bp->b_command == SREV)
				TMADDR->tmbc = bp->b_repcnt;
			TMADDR->tmcs = cmd;
			return;
		}
	}
	if ((blkno = t_blkno) == dbtofsb(bp->b_blkno)) {
		TMADDR->tmbc = -bp->b_bcount;
		s = spl6();
		if (tm_ubinfo == 0)
			tm_ubinfo = ubasetup(bp,1);
		splx(s);
		if ((bp->b_flags&B_READ) == 0) {
			if (tmtab.b_errcnt)
				cmd |= WIRG;
			else
				cmd |= WCOM;
		} else
			cmd |= RCOM;
		cmd |= (tm_ubinfo >> 12) & 0x30;
		tmtab.b_active = SIO;
		TMADDR->tmba = tm_ubinfo;
		TMADDR->tmcs = cmd; 
		return;
	}
	tmtab.b_active = SSEEK;
	if (blkno < dbtofsb(bp->b_blkno)) {
		cmd |= SFORW;
		TMADDR->tmbc = blkno - dbtofsb(bp->b_blkno);
	} else {
		cmd |= SREV;
		TMADDR->tmbc = dbtofsb(bp->b_blkno) - blkno;
	}
	TMADDR->tmcs = cmd;
	return;

next:
	ubarelse(&tm_ubinfo);
	tmtab.b_actf = bp->av_forw;
	iodone(bp);
	goto loop;
}

tmintr()
{
	register struct buf *bp;
	register state;

	if (t_flags&WAITREW && (TMADDR->tmer&RWS) == 0) {
		t_flags &= ~WAITREW;
		wakeup((caddr_t)&t_flags);
	}
	if ((bp = tmtab.b_actf) == NULL)
		return;
	t_dsreg = TMADDR->tmcs;
	t_erreg = TMADDR->tmer;
	t_resid = TMADDR->tmbc;
	if ((bp->b_flags & B_READ) == 0)
		t_flags |= LASTIOW;
	state = tmtab.b_active;
	tmtab.b_active = 0;
	if (TMADDR->tmcs&ERROR) {
		while(TMADDR->tmer & SDWN)
			;			/* await settle down */
		if (TMADDR->tmer&EOF) {
			tmseteof(bp);	/* set blkno and nxrec */
			state = SCOM;
			TMADDR->tmbc = -bp->b_bcount;
			goto errout;
		}
		if ((bp->b_flags&B_READ) && (TMADDR->tmer&(HARD|SOFT)) == RLE)
			goto out;
		if ((TMADDR->tmer&HARD)==0 && state==SIO) {
			if (++tmtab.b_errcnt < 7) {
				if((TMADDR->tmer&SOFT) == NXM)
					printf("TM UBA late error\n");
				else
					t_blkno += 2;		/* ???????? */
				ubarelse(&tm_ubinfo);
				tmstart();
				return;
			}
		} else if (t_openf>0 && bp != &rtmbuf)
			t_openf = -1;
		deverror(bp, t_erreg, t_dsreg);
		bp->b_flags |= B_ERROR;
		state = SIO;
	}
out:
	switch (state) {

	case SIO:
		t_blkno++;
		/* fall into ... */

	case SCOM:
		if (bp == &ctmbuf) {
			switch (bp->b_command) {
			case SFORW:
				t_blkno -= bp->b_repcnt;
				break;

			case SREV:
				t_blkno += bp->b_repcnt;
				break;

			default:
				if (++bp->b_repcnt < 0) {
					tmstart();	/* continue */
					return;
				}
			}
		}
errout:
		tmtab.b_errcnt = 0;
		tmtab.b_actf = bp->av_forw;
		bp->b_resid = -TMADDR->tmbc;
		ubarelse(&tm_ubinfo);
		iodone(bp);
		break;

	case SSEEK:
		t_blkno = dbtofsb(bp->b_blkno);
		break;

	default:
		return;
	}
	tmstart();
}

tmseteof(bp)
	register struct buf *bp;
{

	if (bp == &ctmbuf) {
		if (t_blkno > dbtofsb(bp->b_blkno)) {
			/* reversing */
			t_nxrec = dbtofsb(bp->b_blkno) - TMADDR->tmbc;
			t_blkno = t_nxrec;
		} else {
			/* spacing forward */
			t_blkno = dbtofsb(bp->b_blkno) + TMADDR->tmbc;
			t_nxrec = t_blkno - 1;
		}
		return;
	} 
	/* eof on read */
	t_nxrec = dbtofsb(bp->b_blkno);
}

tmread(dev)
{

	tmphys(dev);
	physio(tmstrategy, &rtmbuf, dev, B_READ, minphys);
}

tmwrite(dev)
{

	tmphys(dev);
	physio(tmstrategy, &rtmbuf, dev, B_WRITE, minphys);
}

tmphys(dev)
{
	register daddr_t a;

	a = dbtofsb(u.u_offset >> 9);
	t_blkno = a;
	t_nxrec = a + 1;
}

/*ARGSUSED*/
tmioctl(dev, cmd, addr, flag)
	caddr_t addr;
	dev_t dev;
{
	register callcount;
	int fcount;
	struct mtop mtop;
	struct mtget mtget;
	/* we depend of the values and order of the MT codes here */
	static tmops[] = {WEOF, SFORW, SREV, SFORW, SREV, REW, OFFL};

	switch(cmd) {
		case MTIOCTOP:	/* tape operation */
		if (copyin((caddr_t)addr, (caddr_t)&mtop, sizeof(mtop))) {
			u.u_error = EFAULT;
			return;
		}
		switch(mtop.mt_op) {
		case MTWEOF: case MTFSF: case MTBSF:
			callcount = mtop.mt_count;
			fcount = INF;
			break;
		case MTFSR: case MTBSR:
			callcount = 1;
			fcount = mtop.mt_count;
			break;
		case MTREW: case MTOFFL:
			callcount = 1;
			fcount = 1;
			break;
		default:
			u.u_error = ENXIO;
			return;
		}
		if (callcount <= 0 || fcount <= 0)
			u.u_error = ENXIO;
		else while (--callcount >= 0) {
			tcommand(dev, tmops[mtop.mt_op], fcount);
			if ((mtop.mt_op == MTFSR || mtop.mt_op == MTBSR) &&
			    ctmbuf.b_resid) {
				u.u_error = EIO;
				break;
			}
			if ((ctmbuf.b_flags&B_ERROR) || t_erreg&BOT)
				break;
		}
		geterror(&ctmbuf);
		return;
	case MTIOCGET:
		mtget.mt_dsreg = t_dsreg;
		mtget.mt_erreg = t_erreg;
		mtget.mt_resid = t_resid;
		if (copyout((caddr_t)&mtget, addr, sizeof(mtget)))
			u.u_error = EFAULT;
		return;
	default:
		u.u_error = ENXIO;
	}
}

#define	DBSIZE	20

twall(start, num)
	int start, num;
{
#if VAX==780
	register struct uba_regs *up = (struct uba_regs *)PHYSUBA0;
#endif
	int blk;

	TMPHYS->tmcs = DCLR | GO;
#if VAX==780
	up->uba_cr = ADINIT;
	up->uba_cr = IFS|BRIE|USEFIE|SUEFIE;
	while ((up->uba_cnfgr & UBIC) == 0)
		;
#endif
	while (num > 0) {
		blk = num > DBSIZE ? DBSIZE : num;
		tmdwrite(start, blk);
		start += blk;
		num -= blk;
	}
	((struct uba_regs *)PHYSUBA0)->uba_dpr[1] |= BNE;
}

tmdwrite(buf, num)
register buf, num;
{
	register int *io, npf;

	twait();
	((struct uba_regs *)PHYSUBA0)->uba_dpr[1] |= BNE;
	io = (int *)((struct uba_regs *)PHYSUBA0)->uba_map;
	npf = num+1;
	while (--npf != 0)
		 *io++ = (int)(buf++ | (1<<21) | MRV);
	*io = 0;
	TMPHYS->tmbc = -(num*NBPG);
	TMPHYS->tmba = 0;
	TMPHYS->tmcs = WCOM | GO | D800;
}

twait()
{
	register s;

	do
		s = TMPHYS->tmcs;
	while ((s & CUR) == 0);
}

rewind()
{

	twait();
	TMPHYS->tmcs = REW | GO;
}

teof()
{

	twait();
	TMPHYS->tmcs = WEOF | GO | D800;
}
#endif
Commit	Line	Data
b28deaf8	1	/* tm.c 4.5 %G% */
d75e5c3e	2
66b4fb09	3	#include "tm.h"
d75e5c3e BJ	4	#if NTM > 0
	5	/*
	6	* TM tape driver
	7	*/
	8
	9	#include "../h/param.h"
	10	#include "../h/buf.h"
	11	#include "../h/dir.h"
	12	#include "../h/conf.h"
	13	#include "../h/user.h"
	14	#include "../h/file.h"
	15	#include "../h/map.h"
	16	#include "../h/pte.h"
	17	#include "../h/uba.h"
	18	#include "../h/mtio.h"
	19	#include "../h/ioctl.h"
	20	#include "../h/vm.h"
	21
	22	struct device {
	23	u_short tmer;
	24	u_short tmcs;
	25	short tmbc;
	26	u_short tmba;
	27	short tmdb;
	28	short tmrd;
	29	};
	30
	31	#define b_repcnt b_bcount
	32	#define b_command b_resid
	33
	34	struct buf tmtab;
	35	struct buf ctmbuf;
	36	struct buf rtmbuf;
	37
	38	int tm_ubinfo;
	39
	40	/* bits in minor device */
	41	#define T_NOREWIND 04
	42	#define T_1600BPI 08
	43
	44	#define INF (daddr_t)1000000L
	45
	46	/*
	47	* Really only handle one tape drive... if you have more than one,
	48	* you can make all these arrays and change the obvious things, but
	49	* it is not clear what happens when some drives are transferring while
	50	* others rewind, so we don't pretend that this driver handles multiple
	51	* tape drives.
	52	*/
	53	char t_openf;
	54	daddr_t t_blkno;
	55	char t_flags;
	56	daddr_t t_nxrec;
	57	u_short t_erreg;
	58	u_short t_dsreg;
	59	short t_resid;
	60
	61	/* bits in tmcs */
	62	#define GO 01
	63	#define OFFL 0
	64	#define RCOM 02
	65	#define WCOM 04
	66	#define WEOF 06
	67	#define SFORW 010
68	#define SREV 012
69	#define WIRG 014
70	#define REW 016
71	#define IENABLE 0100
72	#define CUR 0200
73	#define NOP IENABLE
74	#define DCLR 010000
75	#define D800 060000
76	#define ERROR 0100000
77
78	/* bits in tmer */
79	#define TUR 1
80	#define RWS 02
81	#define WRL 04
82	#define SDWN 010
83	#define BOT 040
84	#define SELR 0100
85	#define NXM 0200
86	#define TMBTE 0400
87	#define RLE 01000
88	#define EOT 02000
89	#define BGL 04000
90	#define PAE 010000
91	#define CRE 020000
92	#define EOF 040000
93	#define ILC 0100000
94
95	#define HARD (ILC\|EOT)
96	#define SOFT (CRE\|PAE\|BGL\|RLE\|TMBTE\|NXM)
97
98	#define SSEEK 1 /* seeking */
99	#define SIO 2 /* doing seq i/o */
100	#define SCOM 3 /* sending control command */
101
102	#define LASTIOW 1 /* last op was a write */
103	#define WAITREW 2 /* someone is waiting for a rewind */
104
105	tmopen(dev, flag)
106	dev_t dev;
107	int flag;
108	{
109	register ds, unit;
110
111	tmtab.b_flags \|= B_TAPE;
112	unit = minor(dev)&03;
113	if (unit >= NTM \|\| t_openf) {
114	u.u_error = ENXIO; /* out of range or open */
115	return;
116	}
117	tcommand(dev, NOP, 1);
118	if ((t_erreg&SELR) == 0) {
119	u.u_error = EIO; /* offline */
120	return;
121	}
122	t_openf = 1;
123	if (t_erreg&RWS)
124	tmwaitrws(dev); /* wait for rewind complete */
125	while (t_erreg&SDWN)
126	tcommand(dev, NOP, 1); /* await settle down */
127	if ((t_erreg&TUR)==0 \|\|
128	((flag&(FREAD\|FWRITE)) == FWRITE && (t_erreg&WRL))) {
129	TMADDR->tmcs = DCLR\|GO;
130	u.u_error = EIO; /* offline or write protect */
131	}
132	if (u.u_error != 0) {
133	t_openf = 0;
134	return;
135	}
136	t_blkno = (daddr_t)0;
137	t_nxrec = INF;
138	t_flags = 0;
139	t_openf = 1;
140	}
141
142	tmwaitrws(dev)
143	register dev;
144	{
145
146	spl5();
147	for (;;) {
0a51498e	148	if ((TMADDR->tmer&RWS) == 0) {
d75e5c3e BJ	149	spl0(); /* rewind complete */
	150	return;
	151	}
	152	t_flags \|= WAITREW;
	153	sleep((caddr_t)&t_flags, PRIBIO);
	154	}
	155	}
	156
	157	tmclose(dev, flag)
	158	register dev_t dev;
	159	register flag;
	160	{
	161
	162	if (flag == FWRITE \|\| ((flag&FWRITE) && (t_flags&LASTIOW))) {
	163	tcommand(dev, WEOF, 1);
	164	tcommand(dev, WEOF, 1);
	165	tcommand(dev, SREV, 1);
	166	}
	167	if ((minor(dev)&T_NOREWIND) == 0)
	168	tcommand(dev, REW, 1);
	169	t_openf = 0;
	170	}
	171
	172	tcommand(dev, com, count)
	173	dev_t dev;
	174	int com, count;
	175	{
	176	register struct buf *bp;
	177
	178	bp = &ctmbuf;
	179	(void) spl5();
	180	while (bp->b_flags&B_BUSY) {
	181	bp->b_flags \|= B_WANTED;
	182	sleep((caddr_t)bp, PRIBIO);
	183	}
	184	bp->b_flags = B_BUSY\|B_READ;
	185	(void) spl0();
	186	bp->b_dev = dev;
	187	bp->b_repcnt = -count;
	188	bp->b_command = com;
	189	bp->b_blkno = 0;
	190	tmstrategy(bp);
	191	iowait(bp);
	192	if (bp->b_flags&B_WANTED)
	193	wakeup((caddr_t)bp);
	194	bp->b_flags &= B_ERROR;
	195	}
	196
	197	tmstrategy(bp)
	198	register struct buf *bp;
	199	{
	200	register daddr_t *p;
	201
0a51498e	202	tmwaitrws(bp->b_dev);
d75e5c3e BJ	203	if (bp != &ctmbuf) {
	204	p = &t_nxrec;
	205	if (dbtofsb(bp->b_blkno) > *p) {
	206	bp->b_flags \|= B_ERROR;
	207	bp->b_error = ENXIO; /* past EOF */
	208	iodone(bp);
	209	return;
	210	} else if (dbtofsb(bp->b_blkno) == *p && bp->b_flags&B_READ) {
	211	bp->b_resid = bp->b_bcount;
	212	clrbuf(bp); /* at EOF */
	213	iodone(bp);
	214	return;
	215	} else if ((bp->b_flags&B_READ) == 0)
	216	p = dbtofsb(bp->b_blkno) + 1; / write sets EOF */
	217	}
	218	bp->av_forw = NULL;
	219	(void) spl5();
	220	if (tmtab.b_actf == NULL)
	221	tmtab.b_actf = bp;
	222	else
	223	tmtab.b_actl->av_forw = bp;
	224	tmtab.b_actl = bp;
	225	if (tmtab.b_active == 0)
	226	tmstart();
	227	(void) spl0();
	228	}
	229
	230	tmstart()
	231	{
	232	register struct buf *bp;
	233	register cmd;
	234	register daddr_t blkno;
b28deaf8	235	int s;
d75e5c3e BJ	236
	237	loop:
	238	if ((bp = tmtab.b_actf) == 0)
	239	return;
	240	t_dsreg = TMADDR->tmcs;
	241	t_erreg = TMADDR->tmer;
	242	t_resid = TMADDR->tmbc;
	243	t_flags &= ~LASTIOW;
	244	if (t_openf < 0 \|\| (TMADDR->tmcs&CUR) == 0) {
	245	/* t_openf = -1; ??? */
	246	bp->b_flags \|= B_ERROR; /* hard error'ed or !SELR */
	247	goto next;
	248	}
	249	cmd = IENABLE \| GO;
	250	if ((minor(bp->b_dev) & T_1600BPI) == 0)
	251	cmd \|= D800;
	252	if (bp == &ctmbuf) {
	253	if (bp->b_command == NOP)
	254	goto next; /* just get status */
	255	else {
	256	cmd \|= bp->b_command;
	257	tmtab.b_active = SCOM;
	258	if (bp->b_command == SFORW \|\| bp->b_command == SREV)
	259	TMADDR->tmbc = bp->b_repcnt;
	260	TMADDR->tmcs = cmd;
	261	return;
	262	}
	263	}
	264	if ((blkno = t_blkno) == dbtofsb(bp->b_blkno)) {
	265	TMADDR->tmbc = -bp->b_bcount;
b28deaf8	266	s = spl6();
d75e5c3e BJ	267	if (tm_ubinfo == 0)
d75e5c3e BJ	268	tm_ubinfo = ubasetup(bp,1);
b28deaf8	269	splx(s);
d75e5c3e BJ	270	if ((bp->b_flags&B_READ) == 0) {
	271	if (tmtab.b_errcnt)
	272	cmd \|= WIRG;
	273	else
	274	cmd \|= WCOM;
	275	} else
	276	cmd \|= RCOM;
	277	cmd \|= (tm_ubinfo >> 12) & 0x30;
	278	tmtab.b_active = SIO;
	279	TMADDR->tmba = tm_ubinfo;
	280	TMADDR->tmcs = cmd;
	281	return;
	282	}
	283	tmtab.b_active = SSEEK;
	284	if (blkno < dbtofsb(bp->b_blkno)) {
	285	cmd \|= SFORW;
	286	TMADDR->tmbc = blkno - dbtofsb(bp->b_blkno);
	287	} else {
	288	cmd \|= SREV;
	289	TMADDR->tmbc = dbtofsb(bp->b_blkno) - blkno;
	290	}
	291	TMADDR->tmcs = cmd;
	292	return;
	293
	294	next:
b28deaf8	295	ubarelse(&tm_ubinfo);
d75e5c3e BJ	296	tmtab.b_actf = bp->av_forw;
	297	iodone(bp);
	298	goto loop;
	299	}
	300
	301	tmintr()
	302	{
	303	register struct buf *bp;
	304	register state;
	305
	306	if (t_flags&WAITREW && (TMADDR->tmer&RWS) == 0) {
	307	t_flags &= ~WAITREW;
	308	wakeup((caddr_t)&t_flags);
	309	}
	310	if ((bp = tmtab.b_actf) == NULL)
	311	return;
	312	t_dsreg = TMADDR->tmcs;
d75e5c3e BJ	313	t_erreg = TMADDR->tmer;
	314	t_resid = TMADDR->tmbc;
	315	if ((bp->b_flags & B_READ) == 0)
	316	t_flags \|= LASTIOW;
	317	state = tmtab.b_active;
	318	tmtab.b_active = 0;
	319	if (TMADDR->tmcs&ERROR) {
	320	while(TMADDR->tmer & SDWN)
	321	; /* await settle down */
	322	if (TMADDR->tmer&EOF) {
	323	tmseteof(bp); /* set blkno and nxrec */
	324	state = SCOM;
	325	TMADDR->tmbc = -bp->b_bcount;
	326	goto errout;
	327	}
	328	if ((bp->b_flags&B_READ) && (TMADDR->tmer&(HARD\|SOFT)) == RLE)
	329	goto out;
	330	if ((TMADDR->tmer&HARD)==0 && state==SIO) {
0a51498e	331	if (++tmtab.b_errcnt < 7) {
d75e5c3e BJ	332	if((TMADDR->tmer&SOFT) == NXM)
	333	printf("TM UBA late error\n");
	334	else
0a51498e	335	t_blkno += 2; /* ???????? */
b28deaf8	336	ubarelse(&tm_ubinfo);
d75e5c3e BJ	337	tmstart();
	338	return;
	339	}
	340	} else if (t_openf>0 && bp != &rtmbuf)
	341	t_openf = -1;
0a51498e	342	deverror(bp, t_erreg, t_dsreg);
d75e5c3e BJ	343	bp->b_flags \|= B_ERROR;
	344	state = SIO;
	345	}
	346	out:
	347	switch (state) {
	348
	349	case SIO:
	350	t_blkno++;
	351	/* fall into ... */
	352
	353	case SCOM:
	354	if (bp == &ctmbuf) {
	355	switch (bp->b_command) {
	356	case SFORW:
	357	t_blkno -= bp->b_repcnt;
	358	break;
	359
	360	case SREV:
	361	t_blkno += bp->b_repcnt;
	362	break;
	363
	364	default:
	365	if (++bp->b_repcnt < 0) {
	366	tmstart(); /* continue */
	367	return;
	368	}
	369	}
	370	}
	371	errout:
	372	tmtab.b_errcnt = 0;
	373	tmtab.b_actf = bp->av_forw;
	374	bp->b_resid = -TMADDR->tmbc;
b28deaf8	375	ubarelse(&tm_ubinfo);
d75e5c3e BJ	376	iodone(bp);
	377	break;
	378
	379	case SSEEK:
	380	t_blkno = dbtofsb(bp->b_blkno);
	381	break;
	382
	383	default:
	384	return;
	385	}
	386	tmstart();
	387	}
	388
	389	tmseteof(bp)
	390	register struct buf *bp;
	391	{
	392
	393	if (bp == &ctmbuf) {
	394	if (t_blkno > dbtofsb(bp->b_blkno)) {
	395	/* reversing */
	396	t_nxrec = dbtofsb(bp->b_blkno) - TMADDR->tmbc;
	397	t_blkno = t_nxrec;
	398	} else {
	399	/* spacing forward */
	400	t_blkno = dbtofsb(bp->b_blkno) + TMADDR->tmbc;
	401	t_nxrec = t_blkno - 1;
	402	}
	403	return;
	404	}
	405	/* eof on read */
	406	t_nxrec = dbtofsb(bp->b_blkno);
	407	}
	408
	409	tmread(dev)
	410	{
	411
	412	tmphys(dev);
	413	physio(tmstrategy, &rtmbuf, dev, B_READ, minphys);
	414	}
	415
	416	tmwrite(dev)
	417	{
	418
	419	tmphys(dev);
	420	physio(tmstrategy, &rtmbuf, dev, B_WRITE, minphys);
	421	}
	422
	423	tmphys(dev)
	424	{
	425	register daddr_t a;
	426
	427	a = dbtofsb(u.u_offset >> 9);
	428	t_blkno = a;
	429	t_nxrec = a + 1;
	430	}
	431
	432	/ARGSUSED/
	433	tmioctl(dev, cmd, addr, flag)
	434	caddr_t addr;
	435	dev_t dev;
	436	{
	437	register callcount;
	438	int fcount;
	439	struct mtop mtop;
440	struct mtget mtget;
441	/* we depend of the values and order of the MT codes here */
442	static tmops[] = {WEOF, SFORW, SREV, SFORW, SREV, REW, OFFL};
443
444	switch(cmd) {
445	case MTIOCTOP: /* tape operation */
446	if (copyin((caddr_t)addr, (caddr_t)&mtop, sizeof(mtop))) {
447	u.u_error = EFAULT;
448	return;
449	}
450	switch(mtop.mt_op) {
451	case MTWEOF: case MTFSF: case MTBSF:
452	callcount = mtop.mt_count;
453	fcount = INF;
454	break;
455	case MTFSR: case MTBSR:
456	callcount = 1;
457	fcount = mtop.mt_count;
458	break;
459	case MTREW: case MTOFFL:
460	callcount = 1;
461	fcount = 1;
462	break;
463	default:
464	u.u_error = ENXIO;
465	return;
466	}
467	if (callcount <= 0 \|\| fcount <= 0)
468	u.u_error = ENXIO;
469	else while (--callcount >= 0) {
470	tcommand(dev, tmops[mtop.mt_op], fcount);
471	if ((mtop.mt_op == MTFSR \|\| mtop.mt_op == MTBSR) &&
472	ctmbuf.b_resid) {
473	u.u_error = EIO;
474	break;
475	}
476	if ((ctmbuf.b_flags&B_ERROR) \|\| t_erreg&BOT)
477	break;
478	}
479	geterror(&ctmbuf);
480	return;
481	case MTIOCGET:
482	mtget.mt_dsreg = t_dsreg;
483	mtget.mt_erreg = t_erreg;
484	mtget.mt_resid = t_resid;
485	if (copyout((caddr_t)&mtget, addr, sizeof(mtget)))
486	u.u_error = EFAULT;
487	return;
488	default:
489	u.u_error = ENXIO;
490	}
491	}
492
493	#define DBSIZE 20
494
495	twall(start, num)
496	int start, num;
497	{
498	#if VAX==780
499	register struct uba_regs up = (struct uba_regs )PHYSUBA0;
500	#endif
501	int blk;
502
503	TMPHYS->tmcs = DCLR \| GO;
504	#if VAX==780
505	up->uba_cr = ADINIT;
506	up->uba_cr = IFS\|BRIE\|USEFIE\|SUEFIE;
507	while ((up->uba_cnfgr & UBIC) == 0)
508	;
509	#endif
510	while (num > 0) {
511	blk = num > DBSIZE ? DBSIZE : num;
512	tmdwrite(start, blk);
513	start += blk;
514	num -= blk;
515	}
0a51498e	516	((struct uba_regs *)PHYSUBA0)->uba_dpr[1] \|= BNE;
d75e5c3e BJ	517	}
	518
	519	tmdwrite(buf, num)
	520	register buf, num;
	521	{
	522	register int *io, npf;
0a51498e	523
5f550cff	524	twait();
0a51498e	525	((struct uba_regs *)PHYSUBA0)->uba_dpr[1] \|= BNE;
d75e5c3e BJ	526	io = (int )((struct uba_regs )PHYSUBA0)->uba_map;
d75e5c3e BJ	527	npf = num+1;
0a51498e	528	while (--npf != 0)
d75e5c3e BJ	529	*io++ = (int)(buf++ \| (1<<21) \| MRV);
	530	*io = 0;
	531	TMPHYS->tmbc = -(num*NBPG);
	532	TMPHYS->tmba = 0;
	533	TMPHYS->tmcs = WCOM \| GO \| D800;
	534	}
	535
5f550cff	536	twait()
d75e5c3e	537	{
0a51498e	538	register s;
d75e5c3e BJ	539
	540	do
	541	s = TMPHYS->tmcs;
	542	while ((s & CUR) == 0);
	543	}
	544
5f550cff	545	rewind()
d75e5c3e BJ	546	{
d75e5c3e BJ	547
5f550cff	548	twait();
d75e5c3e BJ	549	TMPHYS->tmcs = REW \| GO;
	550	}
	551
5f550cff	552	teof()
d75e5c3e BJ	553	{
d75e5c3e BJ	554
5f550cff	555	twait();
d75e5c3e BJ	556	TMPHYS->tmcs = WEOF \| GO \| D800;
	557	}
	558	#endif