From: CSRG <csrg@ucbvax.Berkeley.EDU>
Date: Wed, 11 Nov 1981 06:42:18 +0000 (-0800)
Subject: BSD 4_1_snap development
X-Git-Tag: BSD-4_1_snap~134
X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/commitdiff_plain/eb016ef3a17d824e8a98013356df44f3967dae05

BSD 4_1_snap development
Work on file sys/dev/mt.c

Synthesized-from: CSRG/cd1/4.1.snap
---

diff --git a/sys/dev/mt.c b/sys/dev/mt.c
new file mode 100644
index 0000000000..48113e251c
--- /dev/null
+++ b/sys/dev/mt.c
@@ -0,0 +1,645 @@
+/*	mt.c	1.2	81/10/27	*/
+
+#include "mu.h"
+#if NMT > 0
+/*
+ * TM78/TU78 tape driver
+ *
+ *	Behavior in complex error situations is uncertain...
+ *
+ * TODO:
+ *	test error recovery
+ *	add odd byte count kludge from VMS driver
+ *	write dump routine
+ */
+#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/mbareg.h"
+#include "../h/mbavar.h"
+#include "../h/mtio.h"
+#include "../h/ioctl.h"
+#include "../h/cmap.h"
+#include "../h/cpu.h"
+
+#include "../h/mtreg.h"
+
+struct	buf	rmtbuf[NMT];
+struct	buf	cmtbuf[NMT];
+
+short	mttypes[] =
+	{ MBDT_TU78, 0 };
+struct	mba_device *mtinfo[NMT];
+int	mtattach(), mtslave(), mtustart(), mtstart(), mtndtint(), mtdtint();
+struct	mba_driver mtdriver =
+    { mtattach, mtslave, mtustart, mtstart, mtdtint, mtndtint,
+      mttypes, "mt", "mu", mtinfo };
+
+#define MASKREG(r)	((r) & 0xffff)
+
+/* bits in minor device */
+#define	MUUNIT(dev)	(minor(dev)&03)
+#define	H_NOREWIND	04
+#define	H_6250BPI	08
+
+#define MTUNIT(dev)	(mutomt[MUUNIT(dev)])
+
+#define	INF	(daddr_t)1000000L	/* a block number that wont exist */
+
+struct	mu_softc {
+	char	sc_openf;
+	char	sc_flags;
+	daddr_t	sc_blkno;
+	daddr_t	sc_nxrec;
+	u_short	sc_erreg;
+	u_short	sc_dsreg;
+	short	sc_resid;
+	short	sc_dens;
+	struct	mba_device *sc_mi;
+	int	sc_slave;
+} mu_softc[NMU];
+short	mutomt[NMU];
+
+/*
+ * Bits for sc_flags.
+ */
+#define	H_WRITTEN 1	/* last operation was a write */
+
+char	mtds_bits[] = MTDS_BITS;
+
+/*ARGSUSED*/
+mtattach(mi)
+	struct mba_device *mi;
+{
+
+}
+
+mtslave(mi, ms)
+	struct mba_device *mi;
+	struct mba_slave *ms;
+{
+	register struct mu_softc *sc = &mu_softc[ms->ms_unit];
+	register struct mtdevice *mtaddr = (struct mtdevice *)mi->mi_drv;
+	int s = spl7(), rtn = 0;
+
+	mtaddr->mtas = -1;
+	mtaddr->mtncs[ms->ms_slave] = MT_SENSE|MT_GO;
+	while (mtaddr->mtas == 0)
+		;
+	if ((mtaddr->mtner & MTER_INTCODE) == MTER_DONE &&
+	    (mtaddr->mtds & MTDS_PRES)) {
+		sc->sc_mi = mi;
+		sc->sc_slave = ms->ms_slave;
+		mutomt[ms->ms_unit] = mi->mi_unit;
+		rtn = 1;
+	}
+	mtaddr->mtas = mtaddr->mtas;
+	splx(s);
+	return (rtn);
+}
+
+mtopen(dev, flag)
+	dev_t dev;
+	int flag;
+{
+	register int muunit;
+	register struct mba_device *mi;
+	register struct mu_softc *sc;
+	int olddens, dens;
+
+	muunit = MUUNIT(dev);
+	if (muunit >= NMU || (sc = &mu_softc[muunit])->sc_openf ||
+	    (mi = mtinfo[MTUNIT(dev)]) == 0 || mi->mi_alive == 0) {
+		u.u_error = ENXIO;
+		return;
+	}
+	olddens = sc->sc_dens;
+	dens = sc->sc_dens = (minor(dev)&H_6250BPI) ? MT_GCR : 0;
+	mtcommand(dev, MT_SENSE, 1);
+	sc->sc_dens = olddens;
+	if ((sc->sc_dsreg & MTDS_ONL) == 0) {
+		uprintf("mu%d: not online\n", muunit);
+		u.u_error = EIO;
+		return;
+	}
+	if ((flag&FWRITE) && (sc->sc_dsreg&MTDS_FPT)) {
+		uprintf("mu%d: no write ring\n", muunit);
+		u.u_error = EIO;
+		return;
+	}
+	if ((sc->sc_dsreg & MTDS_BOT) == 0 && (flag&FWRITE) &&
+	    dens != sc->sc_dens) {
+		uprintf("mu%d: can't change density in mid-tape\n", muunit);
+		u.u_error = EIO;
+		return;
+	}
+	sc->sc_openf = 1;
+	sc->sc_blkno = (daddr_t)0;
+	sc->sc_nxrec = INF;
+	sc->sc_flags = 0;
+	sc->sc_dens = dens;
+}
+
+mtclose(dev, flag)
+	register dev_t dev;
+	register flag;
+{
+	register struct mu_softc *sc = &mu_softc[MUUNIT(dev)];
+
+	if (flag == FWRITE || ((flag&FWRITE) && (sc->sc_flags&H_WRITTEN)))
+		mtcommand(dev, MT_CLS|sc->sc_dens, 1);
+	if ((minor(dev)&H_NOREWIND) == 0)
+		mtcommand(dev, MT_REW, 0);
+	sc->sc_openf = 0;
+}
+
+mtcommand(dev, com, count)
+	dev_t dev;
+	int com, count;
+{
+	register struct buf *bp;
+
+	bp = &cmtbuf[MTUNIT(dev)];
+	(void) spl5();
+	while (bp->b_flags&B_BUSY) {
+		if(bp->b_repcnt == 0 && (bp->b_flags&B_DONE))
+			break;
+		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_command = com;
+	bp->b_repcnt = count;
+	bp->b_blkno = 0;
+	mtstrategy(bp);
+	if (count == 0)
+		return;
+	iowait(bp);
+	if (bp->b_flags&B_WANTED)
+		wakeup((caddr_t)bp);
+	bp->b_flags &= B_ERROR;
+}
+
+mtstrategy(bp)
+	register struct buf *bp;
+{
+	register struct mba_device *mi = mtinfo[MTUNIT(bp->b_dev)];
+	register struct buf *dp;
+
+	bp->av_forw = NULL;
+	dp = &mi->mi_tab;
+	(void) spl5();
+	if (dp->b_actf == NULL)
+		dp->b_actf = bp;
+	else
+		dp->b_actl->av_forw = bp;
+	dp->b_actl = bp;
+	if (dp->b_active == 0)
+		mbustart(mi);
+	(void) spl0();
+}
+
+mtustart(mi)
+	register struct mba_device *mi;
+{
+	register struct mtdevice *mtaddr =
+	    (struct mtdevice *)mi->mi_drv;
+	register struct buf *bp = mi->mi_tab.b_actf;
+	register struct mu_softc *sc = &mu_softc[MUUNIT(bp->b_dev)];
+	daddr_t blkno;
+
+	sc->sc_flags &= ~H_WRITTEN;
+	if (sc->sc_openf < 0) {
+		bp->b_flags |= B_ERROR;
+		return (MBU_NEXT);
+	}
+	if (bp != &cmtbuf[MTUNIT(bp->b_dev)]) {
+		if (dbtofsb(bp->b_blkno) > sc->sc_nxrec) {
+			bp->b_flags |= B_ERROR;
+			bp->b_error = ENXIO;
+			return (MBU_NEXT);
+		}
+		if (dbtofsb(bp->b_blkno) == sc->sc_nxrec &&
+		    bp->b_flags&B_READ) {
+			bp->b_resid = bp->b_bcount;
+			clrbuf(bp);
+			return (MBU_NEXT);
+		}
+		if ((bp->b_flags&B_READ)==0)
+			sc->sc_nxrec = dbtofsb(bp->b_blkno) + 1;
+	} else {
+		mtaddr->mtncs[MUUNIT(bp->b_dev)] =
+			(bp->b_repcnt<<8)|bp->b_command|MT_GO;
+		return (MBU_STARTED);
+	}
+	if ((blkno = sc->sc_blkno) == dbtofsb(bp->b_blkno)) {
+		if (mi->mi_tab.b_errcnt == 2) {
+			mtaddr->mtca = MUUNIT(bp->b_dev);
+		} else {
+			mtaddr->mtbc = bp->b_bcount;
+			mtaddr->mtca = (1<<2)|MUUNIT(bp->b_dev);
+		}
+		return (MBU_DODATA);
+	}
+	if (blkno < dbtofsb(bp->b_blkno))
+		mtaddr->mtncs[MUUNIT(bp->b_dev)] =
+		  (min(dbtofsb(bp->b_blkno) - blkno, 0377)<<8)| MT_SFORW|MT_GO;
+	else
+		mtaddr->mtncs[MUUNIT(bp->b_dev)] =
+		  (min(blkno - dbtofsb(bp->b_blkno), 0377)<<8)| MT_SREV|MT_GO;
+	return (MBU_STARTED);
+}
+
+mtstart(mi)
+	register struct mba_device *mi;
+{
+	register struct buf *bp = mi->mi_tab.b_actf;
+	register struct mu_softc *sc = &mu_softc[MUUNIT(bp->b_dev)];
+
+	if (bp->b_flags & B_READ)
+		if (mi->mi_tab.b_errcnt == 2)
+			return(MT_READREV|MT_GO);
+		else
+			return(MT_READ|MT_GO);
+	else
+		return(MT_WRITE|sc->sc_dens|MT_GO);
+}
+
+mtdtint(mi, mbsr)
+	register struct mba_device *mi;
+	int mbsr;
+{
+	register struct mtdevice *mtaddr = (struct mtdevice *)mi->mi_drv;
+	register struct buf *bp = mi->mi_tab.b_actf;
+	register struct mu_softc *sc;
+
+	/* I'M NOT SURE IF THIS SHOULD ALWAYS BE THE CASE SO FOR NOW... */
+	if ((mtaddr->mtca&3) != MUUNIT(bp->b_dev)) {
+		printf("mt: wrong unit!\n");
+		mtaddr->mtca = MUUNIT(bp->b_dev);
+	}
+	sc = &mu_softc[MUUNIT(bp->b_dev)];
+	sc->sc_erreg = mtaddr->mter;
+	if((bp->b_flags & B_READ) == 0)
+		sc->sc_flags |= H_WRITTEN;
+	switch (sc->sc_erreg & MTER_INTCODE) {
+	case MTER_DONE:
+	case MTER_LONGREC:
+		if (mi->mi_tab.b_errcnt != 2)
+			sc->sc_blkno++;
+		bp->b_resid = 0;
+		break;
+
+	case MTER_NOTCAP:
+		printf("mu%d: blank tape\n", MUUNIT(bp->b_dev));
+		goto err;
+
+	case MTER_TM:
+	case MTER_EOT:
+		sc->sc_blkno++;
+	err:
+		bp->b_resid = bp->b_bcount;
+		sc->sc_nxrec = dbtofsb(bp->b_blkno);
+		break;
+
+	case MTER_SHRTREC:
+		sc->sc_blkno++;
+		if (bp != &rmtbuf[MTUNIT(bp->b_dev)])
+			bp->b_flags |= B_ERROR;
+		if (mi->mi_tab.b_errcnt == 2)
+			bp->b_bcount = bp->b_resid;	/* restore saved value */
+		bp->b_resid = bp->b_bcount - mtaddr->mtbc;
+		break;
+
+	case MTER_RDOPP:
+		mi->mi_tab.b_errcnt = 2;	/* indicate "read opposite" */
+		bp->b_resid = bp->b_bcount;	/* save it */
+		bp->b_bcount = mtaddr->mtbc;	/* use this instead */
+		return(MBD_RETRY);
+
+	case MTER_RETRY:
+		mi->mi_tab.b_errcnt = 1;	/* indicate simple retry */
+		return(MBD_RETRY);
+
+	case MTER_OFFLINE:
+		if (sc->sc_openf > 0) {
+			sc->sc_openf = -1;
+			printf("mu%d: offline\n", MUUNIT(bp->b_dev));
+		}
+		bp->b_flags |= B_ERROR;
+		break;
+
+	case MTER_FPT:
+		printf("mu%d: no write ring\n", MUUNIT(bp->b_dev));
+		bp->b_flags |= B_ERROR;
+		break;
+
+	default:
+		printf("mu%d: hard error bn%d mbsr=%b er=%x ds=%b\n",
+		    MUUNIT(bp->b_dev), bp->b_blkno,
+		    mbsr, mbsr_bits, sc->sc_erreg,
+		    sc->sc_dsreg, mtds_bits);
+		bp->b_flags |= B_ERROR;
+		mtaddr->mtid = MTID_CLR;		/* reset the TM78 */
+		DELAY(250);
+		while ((mtaddr->mtid & MTID_RDY) == 0)	/* wait for it */
+			;
+		return (MBD_DONE);
+	}
+	/* CHECK FOR MBA ERROR WHEN NO OTHER ERROR INDICATED? */
+	return (MBD_DONE);
+}
+
+mtndtint(mi)
+	register struct mba_device *mi;
+{
+	register struct mtdevice *mtaddr = (struct mtdevice *)mi->mi_drv;
+	register struct buf *bp = mi->mi_tab.b_actf;
+	register struct mu_softc *sc;
+	int er, fc, unit;
+
+	unit = (mtaddr->mtner >> 8) & 3;
+	er = MASKREG(mtaddr->mtner);
+	/* WILL THIS OCCUR IF ANOTHER DRIVE COMES ONLINE? */
+	if (bp == 0 || unit != MUUNIT(bp->b_dev)) {	/* consistency check */
+		if ((er & MTER_INTCODE) != MTER_ONLINE)
+			printf("mt: unit %d random interrupt\n", unit);
+		return (MBN_SKIP);
+	}
+	if (bp == 0)
+		return (MBN_SKIP);
+	fc = (mtaddr->mtncs[unit] >> 8) & 0xff;
+	sc = &mu_softc[unit];
+	sc->sc_erreg = er;
+	sc->sc_resid = fc;
+	switch (er & MTER_INTCODE) {
+	case MTER_DONE:
+		if (bp == &cmtbuf[MTUNIT(bp->b_dev)]) {
+	done:
+			if (bp->b_command == MT_SENSE)
+				sc->sc_dsreg = MASKREG(mtaddr->mtds);
+			bp->b_resid = fc;
+			return (MBN_DONE);
+		}
+		/* this is UGLY!  (but is it correct?) */
+		if ((fc = dbtofsb(bp->b_blkno) - sc->sc_blkno) < 0)
+			sc->sc_blkno -= min(0377, -fc);
+		else
+			sc->sc_blkno += min(0377, fc);
+		return (MBN_RETRY);
+
+	case MTER_RWDING:
+		return (MBN_SKIP);	/* ignore "rewind started" interrupt */
+
+	case MTER_NOTCAP:
+		printf("mu%d: blank tape\n", MUUNIT(bp->b_dev));
+
+	case MTER_TM:
+	case MTER_EOT:
+	case MTER_LEOT:
+		if (sc->sc_blkno > dbtofsb(bp->b_blkno)) {
+			sc->sc_nxrec = dbtofsb(bp->b_blkno) + fc;
+			sc->sc_blkno = sc->sc_nxrec;
+		} else {
+			sc->sc_blkno = dbtofsb(bp->b_blkno) - fc;
+			sc->sc_nxrec = sc->sc_blkno - 1;
+		}
+		return (MBN_RETRY);
+
+	case MTER_FPT:
+		printf("mu%d: no write ring\n", MUUNIT(bp->b_dev));
+		bp->b_flags |= B_ERROR;
+		return (MBN_DONE);
+
+	case MTER_OFFLINE:
+		if (sc->sc_openf > 0) {
+			sc->sc_openf = -1;
+			printf("mu%d: offline\n", MUUNIT(bp->b_dev));
+		}
+		bp->b_flags |= B_ERROR;
+		return (MBN_DONE);
+
+	case MTER_BOT:
+		if (bp == &cmtbuf[MTUNIT(bp->b_dev)])
+			goto done;
+		/* FALL THROUGH */
+
+	default:
+		printf("mu%d: hard error bn%d er=%o ds=%b\n",
+		    MUUNIT(bp->b_dev), bp->b_blkno,
+		    sc->sc_erreg, sc->sc_dsreg, mtds_bits);
+		mtaddr->mtid = MTID_CLR;		/* reset the TM78 */
+		DELAY(250);
+		while ((mtaddr->mtid & MTID_RDY) == 0)	/* wait for it */
+			;
+		bp->b_flags |= B_ERROR;
+		return (MBN_DONE);
+	}
+	/* NOTREACHED */
+}
+
+mtread(dev)
+	dev_t dev;
+{
+
+	mtphys(dev);
+	if (u.u_error)
+		return;
+	physio(mtstrategy, &rmtbuf[MTUNIT(dev)], dev, B_READ, minphys);
+}
+
+mtwrite(dev)
+{
+
+	mtphys(dev);
+	if (u.u_error)
+		return;
+	physio(mtstrategy, &rmtbuf[MTUNIT(dev)], dev, B_WRITE, minphys);
+}
+
+mtphys(dev)
+	dev_t dev;
+{
+	register int mtunit;
+	register struct mu_softc *sc;
+	register struct mba_device *mi;
+	daddr_t a;
+
+	mtunit = MTUNIT(dev);
+	if (mtunit >= NMT || (mi = mtinfo[mtunit]) == 0 || mi->mi_alive == 0) {
+		u.u_error = ENXIO;
+		return;
+	}
+	a = u.u_offset >> 9;
+	sc = &mu_softc[MUUNIT(dev)];
+	sc->sc_blkno = dbtofsb(a);
+	sc->sc_nxrec = dbtofsb(a)+1;
+}
+
+/*ARGSUSED*/
+mtioctl(dev, cmd, addr, flag)
+	dev_t dev;
+	int cmd;
+	caddr_t addr;
+	int flag;
+{
+	register struct mu_softc *sc = &mu_softc[MUUNIT(dev)];
+	register struct buf *bp = &cmtbuf[MTUNIT(dev)];
+	register callcount;
+	register int n, op;
+	int fcount;
+	struct mtop mtop;
+	struct mtget mtget;
+	/* we depend of the values and order of the MT codes here */
+	static mtops[] =
+	{MT_WTM,MT_SFORWF,MT_SREVF,MT_SFORW,MT_SREV,MT_REW,MT_UNLOAD,MT_SENSE};
+
+	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:
+			callcount = mtop.mt_count;
+			fcount = 1;
+			break;
+		case MTFSF: case MTBSF:
+			callcount = mtop.mt_count;
+			fcount = 1;
+			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;
+			return;
+		}
+		op = mtops[mtop.mt_op];
+		if (op == MT_WTM)
+			op |= sc->sc_dens;
+		while (--callcount >= 0) {
+			register int n;
+
+			do {
+				n = min(fcount, 0xff);
+				mtcommand(dev, op, n);
+				fcount -= n;
+			} while (fcount);
+			if ((mtop.mt_op == MTFSR || mtop.mt_op == MTBSR) &&
+			    bp->b_resid) {
+				u.u_error = EIO;
+				break;
+			}
+			if (bp->b_flags&B_ERROR)
+				break;
+		}
+		geterror(bp);
+		return;
+	case MTIOCGET:
+		mtget.mt_erreg = sc->sc_erreg;
+		mtget.mt_resid = sc->sc_resid;
+		mtcommand(dev, MT_SENSE, 1);	/* update drive status */
+		mtget.mt_dsreg = sc->sc_dsreg;
+		mtget.mt_type = MT_ISMT;
+		if (copyout((caddr_t)&mtget, addr, sizeof(mtget)))
+			u.u_error = EFAULT;
+		return;
+	default:
+		u.u_error = ENXIO;
+	}
+}
+
+#define	DBSIZE	20
+
+mtdump()
+{
+	register struct mba_device *mi;
+	register struct mba_regs *mp;
+	register struct mtdevice *mtaddr;
+	int blk, num;
+	int start;
+
+	start = 0;
+	num = maxfree;
+#define	phys(a,b)		((b)((int)(a)&0x7fffffff))
+	if (mtinfo[0] == 0)
+		return (ENXIO);
+	mi = phys(mtinfo[0], struct mba_device *);
+	mp = phys(mi->mi_hd, struct mba_hd *)->mh_physmba;
+	mp->mba_cr = MBCR_IE;
+	mtaddr = (struct mtdevice *)&mp->mba_drv[mi->mi_drive];
+#ifdef notyet
+	mtaddr->mttc = MTTC_PDP11|MTTC_1600BPI;
+	mtaddr->mtcs1 = MT_DCLR|MT_GO;
+	while (num > 0) {
+		blk = num > DBSIZE ? DBSIZE : num;
+		mtdwrite(start, blk, mtaddr, mp);
+		start += blk;
+		num -= blk;
+	}
+	mteof(mtaddr);
+	mteof(mtaddr);
+	mtwait(mtaddr);
+	if (mtaddr->mtds&MTDS_ERR)
+		return (EIO);
+	mtaddr->mtcs1 = MT_REW|MT_GO;
+	return (0);
+}
+
+mtdwrite(dbuf, num, mtaddr, mp)
+	register dbuf, num;
+	register struct mtdevice *mtaddr;
+	struct mba_regs *mp;
+{
+	register struct pte *io;
+	register int i;
+
+	mtwait(mtaddr);
+	io = mp->mba_map;
+	for (i = 0; i < num; i++)
+		*(int *)io++ = dbuf++ | PG_V;
+	mtaddr->mtfc = -(num*NBPG);
+	mp->mba_sr = -1;
+	mp->mba_bcr = -(num*NBPG);
+	mp->mba_var = 0;
+	mtaddr->mtcs1 = MT_WCOM|MT_GO;
+}
+
+mtwait(mtaddr)
+	struct mtdevice *mtaddr;
+{
+	register s;
+
+	do
+		s = mtaddr->mtds;
+	while ((s & MTDS_DRY) == 0);
+}
+
+mteof(mtaddr)
+	struct mtdevice *mtaddr;
+{
+
+	mtwait(mtaddr);
+	mtaddr->mtcs1 = MT_WEOF|MT_GO;
+#endif notyet
+}
+#endif