/* $NetBSD: mt.c,v 1.1 1995/10/02 00:28:20 thorpej Exp $ */ /* * Copyright (c) 1992, The University of Utah and * the Computer Systems Laboratory at the University of Utah (CSL). * All rights reserved. * * Permission to use, copy, modify and distribute this software is hereby * granted provided that (1) source code retains these copyright, permission, * and disclaimer notices, and (2) redistributions including binaries * reproduce the notices in supporting documentation, and (3) all advertising * materials mentioning features or use of this software display the following * acknowledgement: ``This product includes software developed by the * Computer Systems Laboratory at the University of Utah.'' * * THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS * IS" CONDITION. THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF * ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * CSL requests users of this software to return to csl-dist@cs.utah.edu any * improvements that they make and grant CSL redistribution rights. * * Utah $Hdr: mt.c 1.8 95/09/12$ */ /* @(#)mt.c 3.9 90/07/10 mt Xinu * * Magnetic tape driver (7974a, 7978a/b, 7979a, 7980a, 7980xc) * Original version contributed by Mt. Xinu. * Modified for 4.4BSD by Mark Davies and Andrew Vignaux, Department of * Computer Science, Victoria University of Wellington */ #include "mt.h" #if NMT > 0 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct mtinfo { u_short hwid; char *desc; } mtinfo[] = { MT7978ID, "7978", MT7979AID, "7979A", MT7980ID, "7980", MT7974AID, "7974A", }; int nmtinfo = sizeof(mtinfo) / sizeof(mtinfo[0]); struct mt_softc { short sc_hpibno; /* logical HPIB this slave it attached to */ short sc_slave; /* HPIB slave address (0-6) */ short sc_flags; /* see below */ u_char sc_lastdsj; /* place for DSJ in mtreaddsj() */ u_char sc_lastecmd; /* place for End Command in mtreaddsj() */ short sc_recvtimeo; /* count of hpibsend timeouts to prevent hang */ short sc_statindex; /* index for next sc_stat when MTF_STATTIMEO */ struct mt_stat sc_stat;/* status bytes last read from device */ short sc_density; /* current density of tape (mtio.h format) */ short sc_type; /* tape drive model (hardware IDs) */ struct devqueue sc_dq; /* HPIB device queue member */ tpr_t sc_ttyp; } mt_softc[NMT]; struct buf mttab[NMT]; struct buf mtbuf[NMT]; #ifdef DEBUG int mtdebug = 0; #define dlog if (mtdebug) log #else #define dlog if (0) log #endif #define UNIT(x) (minor(x) & 3) #define B_CMD B_XXX /* command buf instead of data */ #define b_cmd b_blkno /* blkno holds cmd when B_CMD */ int mtinit(), mtintr(); void mtustart(), mtstart(), mtgo(), mtstrategy(); struct driver mtdriver = { mtinit, "mt", (int (*)()) mtstart, (int (*)()) mtgo, mtintr, }; mtinit(hd) register struct hp_device *hd; { register int unit; register int hpibno = hd->hp_ctlr; register int slave = hd->hp_slave; register struct mt_softc *sc; register int id; register struct buf *bp; for (bp = mttab; bp < &mttab[NMT]; bp++) bp->b_actb = &bp->b_actf; unit = hpibid(hpibno, slave); for (id = 0; id < nmtinfo; id++) if (unit == mtinfo[id].hwid) goto gottype; return (0); /* not a known HP magtape */ gottype: unit = hd->hp_unit; sc = &mt_softc[unit]; sc->sc_type = mtinfo[id].hwid; printf("mt%d: %s tape\n", unit, mtinfo[id].desc); sc->sc_hpibno = hpibno; sc->sc_slave = slave; sc->sc_flags = MTF_EXISTS; sc->sc_dq.dq_ctlr = hpibno; sc->sc_dq.dq_unit = unit; sc->sc_dq.dq_slave = slave; sc->sc_dq.dq_driver = &mtdriver; return (1); } /* * Perform a read of "Device Status Jump" register and update the * status if necessary. If status is read, the given "ecmd" is also * performed, unless "ecmd" is zero. Returns DSJ value, -1 on failure * and -2 on "temporary" failure. */ mtreaddsj(unit, ecmd) register int unit; int ecmd; { register struct mt_softc *sc = &mt_softc[unit]; int retval; if (sc->sc_flags & MTF_STATTIMEO) goto getstats; retval = hpibrecv(sc->sc_hpibno, (sc->sc_flags & MTF_DSJTIMEO) ? -1 : sc->sc_slave, MTT_DSJ, &(sc->sc_lastdsj), 1); sc->sc_flags &= ~MTF_DSJTIMEO; if (retval != 1) { dlog(LOG_DEBUG, "mt%d can't hpibrecv DSJ\n", unit); if (sc->sc_recvtimeo == 0) sc->sc_recvtimeo = hz; if (--sc->sc_recvtimeo == 0) return (-1); if (retval == 0) sc->sc_flags |= MTF_DSJTIMEO; return (-2); } sc->sc_recvtimeo = 0; sc->sc_statindex = 0; dlog(LOG_DEBUG, "mt%d readdsj: 0x%x\n", unit, sc->sc_lastdsj); sc->sc_lastecmd = ecmd; switch (sc->sc_lastdsj) { case 0: if (ecmd & MTE_DSJ_FORCE) break; return (0); case 2: sc->sc_lastecmd = MTE_COMPLETE; case 1: break; default: log(LOG_ERR, "mt%d readdsj: DSJ 0x%x\n", unit, sc->sc_lastdsj); return (-1); } getstats: retval = hpibrecv(sc->sc_hpibno, (sc->sc_flags & MTF_STATCONT) ? -1 : sc->sc_slave, MTT_STAT, ((char *)&(sc->sc_stat)) + sc->sc_statindex, sizeof(sc->sc_stat) - sc->sc_statindex); sc->sc_flags &= ~(MTF_STATTIMEO | MTF_STATCONT); if (retval != sizeof(sc->sc_stat) - sc->sc_statindex) { if (sc->sc_recvtimeo == 0) sc->sc_recvtimeo = hz; if (--sc->sc_recvtimeo != 0) { if (retval >= 0) { sc->sc_statindex += retval; sc->sc_flags |= MTF_STATCONT; } sc->sc_flags |= MTF_STATTIMEO; return (-2); } log(LOG_ERR, "mt%d readdsj: can't read status\n", unit); return (-1); } sc->sc_recvtimeo = 0; sc->sc_statindex = 0; dlog(LOG_DEBUG, "mt%d readdsj: status is %x %x %x %x %x %x\n", unit, sc->sc_stat1, sc->sc_stat2, sc->sc_stat3, sc->sc_stat4, sc->sc_stat5, sc->sc_stat6); if (sc->sc_lastecmd) (void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD, &(sc->sc_lastecmd), 1); return ((int) sc->sc_lastdsj); } mtopen(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { register int unit = UNIT(dev); register struct mt_softc *sc = &mt_softc[unit]; register int req_den; int error; dlog(LOG_DEBUG, "mt%d open: flags 0x%x\n", unit, sc->sc_flags); if (unit >= NMT || (sc->sc_flags & MTF_EXISTS) == 0) return (ENXIO); if (sc->sc_flags & MTF_OPEN) return (EBUSY); sc->sc_flags |= MTF_OPEN; sc->sc_ttyp = tprintf_open(p); if ((sc->sc_flags & MTF_ALIVE) == 0) { error = mtcommand(dev, MTRESET, 0); if (error != 0 || (sc->sc_flags & MTF_ALIVE) == 0) goto errout; if ((sc->sc_stat1 & (SR1_BOT | SR1_ONLINE)) == SR1_ONLINE) (void) mtcommand(dev, MTREW, 0); } for (;;) { if ((error = mtcommand(dev, MTNOP, 0)) != 0) goto errout; if (!(sc->sc_flags & MTF_REW)) break; if (tsleep((caddr_t) &lbolt, PCATCH | (PZERO + 1), "mt", 0) != 0) { error = EINTR; goto errout; } } if ((flag & FWRITE) && (sc->sc_stat1 & SR1_RO)) { error = EROFS; goto errout; } if (!(sc->sc_stat1 & SR1_ONLINE)) { uprintf("mt%d: not online\n", unit); error = EIO; goto errout; } /* * Select density: * - find out what density the drive is set to * (i.e. the density of the current tape) * - if we are going to write * - if we're not at the beginning of the tape * - complain if we want to change densities * - otherwise, select the mtcommand to set the density * * If the drive doesn't support it then don't change the recorded * density. * * The original MOREbsd code had these additional conditions * for the mid-tape change * * req_den != T_BADBPI && * sc->sc_density != T_6250BPI * * which suggests that it would be possible to write multiple * densities if req_den == T_BAD_BPI or the current tape * density was 6250. Testing of our 7980 suggests that the * device cannot change densities mid-tape. * * ajv@comp.vuw.ac.nz */ sc->sc_density = (sc->sc_stat2 & SR2_6250) ? T_6250BPI : ( (sc->sc_stat3 & SR3_1600) ? T_1600BPI : ( (sc->sc_stat3 & SR3_800) ? T_800BPI : -1)); req_den = (dev & T_DENSEL); if (flag & FWRITE) { if (!(sc->sc_stat1 & SR1_BOT)) { if (sc->sc_density != req_den) { uprintf("mt%d: can't change density mid-tape\n", unit); error = EIO; goto errout; } } else { int mtset_density = (req_den == T_800BPI ? MTSET800BPI : ( req_den == T_1600BPI ? MTSET1600BPI : ( req_den == T_6250BPI ? MTSET6250BPI : ( sc->sc_type == MT7980ID ? MTSET6250DC : MTSET6250BPI)))); if (mtcommand(dev, mtset_density, 0) == 0) sc->sc_density = req_den; } } return (0); errout: sc->sc_flags &= ~MTF_OPEN; return (error); } mtclose(dev, flag) dev_t dev; int flag; { register struct mt_softc *sc = &mt_softc[UNIT(dev)]; if (sc->sc_flags & MTF_WRT) { (void) mtcommand(dev, MTWEOF, 2); (void) mtcommand(dev, MTBSF, 0); } if ((minor(dev) & T_NOREWIND) == 0) (void) mtcommand(dev, MTREW, 0); sc->sc_flags &= ~MTF_OPEN; tprintf_close(sc->sc_ttyp); return (0); } mtcommand(dev, cmd, cnt) dev_t dev; int cmd; int cnt; { register struct buf *bp = &mtbuf[UNIT(dev)]; int error = 0; #if 1 if (bp->b_flags & B_BUSY) return (EBUSY); #endif bp->b_cmd = cmd; bp->b_dev = dev; do { bp->b_flags = B_BUSY | B_CMD; mtstrategy(bp); iowait(bp); if (bp->b_flags & B_ERROR) { error = (int) (unsigned) bp->b_error; break; } } while (--cnt > 0); #if 0 bp->b_flags = 0 /*&= ~B_BUSY*/; #else bp->b_flags &= ~B_BUSY; #endif return (error); } /* * Only thing to check here is for legal record lengths (writes only). */ void mtstrategy(bp) register struct buf *bp; { register struct mt_softc *sc; register struct buf *dp; register int unit; register int s; unit = UNIT(bp->b_dev); sc = &mt_softc[unit]; dlog(LOG_DEBUG, "mt%d strategy\n", unit); if ((bp->b_flags & (B_CMD | B_READ)) == 0) { #define WRITE_BITS_IGNORED 8 #if 0 if (bp->b_bcount & ((1 << WRITE_BITS_IGNORED) - 1)) { tprintf(sc->sc_ttyp, "mt%d: write record must be multiple of %d\n", unit, 1 << WRITE_BITS_IGNORED); goto error; } #endif s = 16 * 1024; if (sc->sc_stat2 & SR2_LONGREC) { switch (sc->sc_density) { case T_1600BPI: s = 32 * 1024; break; case T_6250BPI: case T_BADBPI: s = 60 * 1024; break; } } if (bp->b_bcount > s) { tprintf(sc->sc_ttyp, "mt%d: write record (%d) too big: limit (%d)\n", unit, bp->b_bcount, s); error: bp->b_flags |= B_ERROR; bp->b_error = EIO; iodone(bp); return; } } dp = &mttab[unit]; bp->b_actf = NULL; s = splbio(); bp->b_actb = dp->b_actb; *dp->b_actb = bp; dp->b_actb = &bp->b_actf; if (dp->b_active == 0) { dp->b_active = 1; mtustart(unit); } splx(s); } void mtustart(unit) register int unit; { dlog(LOG_DEBUG, "mt%d ustart\n", unit); if (hpibreq(&(mt_softc[unit].sc_dq))) mtstart(unit); } #define hpibppclear(unit) \ { hpib_softc[unit].sc_flags &= ~HPIBF_PPOLL; } void spl_mtintr(unit) int unit; { int s = splbio(); hpibppclear(mt_softc[unit].sc_hpibno); mtintr(unit); (void) splx(s); } void spl_mtstart(unit) int unit; { int s = splbio(); mtstart(unit); (void) splx(s); } void mtstart(unit) register int unit; { register struct mt_softc *sc = &mt_softc[unit]; register struct buf *bp, *dp; short cmdcount = 1; u_char cmdbuf[2]; dlog(LOG_DEBUG, "mt%d start\n", unit); sc->sc_flags &= ~MTF_WRT; bp = mttab[unit].b_actf; if ((sc->sc_flags & MTF_ALIVE) == 0 && ((bp->b_flags & B_CMD) == 0 || bp->b_cmd != MTRESET)) goto fatalerror; if (sc->sc_flags & MTF_REW) { if (!hpibpptest(sc->sc_hpibno, sc->sc_slave)) goto stillrew; switch (mtreaddsj(unit, MTE_DSJ_FORCE|MTE_COMPLETE|MTE_IDLE)) { case 0: case 1: stillrew: if ((sc->sc_stat1 & SR1_BOT) || !(sc->sc_stat1 & SR1_ONLINE)) { sc->sc_flags &= ~MTF_REW; break; } case -2: /* * -2 means "timeout" reading DSJ, which is probably * temporary. This is considered OK when doing a NOP, * but not otherwise. */ if (sc->sc_flags & (MTF_DSJTIMEO | MTF_STATTIMEO)) { timeout(spl_mtstart, (void *)unit, hz >> 5); return; } case 2: if (bp->b_cmd != MTNOP || !(bp->b_flags & B_CMD)) { bp->b_error = EBUSY; goto errdone; } goto done; default: goto fatalerror; } } if (bp->b_flags & B_CMD) { if (sc->sc_flags & MTF_PASTEOT) { switch(bp->b_cmd) { case MTFSF: case MTWEOF: case MTFSR: bp->b_error = ENOSPC; goto errdone; case MTBSF: case MTOFFL: case MTBSR: case MTREW: sc->sc_flags &= ~(MTF_PASTEOT | MTF_ATEOT); break; } } switch(bp->b_cmd) { case MTFSF: if (sc->sc_flags & MTF_HITEOF) goto done; cmdbuf[0] = MTTC_FSF; break; case MTBSF: if (sc->sc_flags & MTF_HITBOF) goto done; cmdbuf[0] = MTTC_BSF; break; case MTOFFL: sc->sc_flags |= MTF_REW; cmdbuf[0] = MTTC_REWOFF; break; case MTWEOF: cmdbuf[0] = MTTC_WFM; break; case MTBSR: cmdbuf[0] = MTTC_BSR; break; case MTFSR: cmdbuf[0] = MTTC_FSR; break; case MTREW: sc->sc_flags |= MTF_REW; cmdbuf[0] = MTTC_REW; break; case MTNOP: /* * NOP is supposed to set status bits. * Force readdsj to do it. */ switch (mtreaddsj(unit, MTE_DSJ_FORCE | MTE_COMPLETE | MTE_IDLE)) { default: goto done; case -1: /* * If this fails, perform a device clear * to fix any protocol problems and (most * likely) get the status. */ bp->b_cmd = MTRESET; break; case -2: timeout(spl_mtstart, (void *)unit, hz >> 5); return; } case MTRESET: /* * 1) selected device clear (send with "-2" secondary) * 2) set timeout, then wait for "service request" * 3) interrupt will read DSJ (and END COMPLETE-IDLE) */ if (hpibsend(sc->sc_hpibno, sc->sc_slave, -2, NULL, 0)){ log(LOG_ERR, "mt%d can't reset\n", unit); goto fatalerror; } timeout(spl_mtintr, (void *)unit, 4 * hz); hpibawait(sc->sc_hpibno, sc->sc_slave); return; case MTSET800BPI: cmdbuf[0] = MTTC_800; break; case MTSET1600BPI: cmdbuf[0] = MTTC_1600; break; case MTSET6250BPI: cmdbuf[0] = MTTC_6250; break; case MTSET6250DC: cmdbuf[0] = MTTC_DC6250; break; } } else { if (sc->sc_flags & MTF_PASTEOT) { bp->b_error = ENOSPC; goto errdone; } if (bp->b_flags & B_READ) { sc->sc_flags |= MTF_IO; cmdbuf[0] = MTTC_READ; } else { sc->sc_flags |= MTF_WRT | MTF_IO; cmdbuf[0] = MTTC_WRITE; cmdbuf[1] = (bp->b_bcount + ((1 << WRITE_BITS_IGNORED) - 1)) >> WRITE_BITS_IGNORED; cmdcount = 2; } } if (hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_TCMD, cmdbuf, cmdcount) == cmdcount) { if (sc->sc_flags & MTF_REW) goto done; hpibawait(sc->sc_hpibno); return; } fatalerror: /* * If anything fails, the drive is probably hosed, so mark it not * "ALIVE" (but it EXISTS and is OPEN or we wouldn't be here, and * if, last we heard, it was REWinding, remember that). */ sc->sc_flags &= MTF_EXISTS | MTF_OPEN | MTF_REW; bp->b_error = EIO; errdone: bp->b_flags |= B_ERROR; done: sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF); iodone(bp); if (dp = bp->b_actf) dp->b_actb = bp->b_actb; else mttab[unit].b_actb = bp->b_actb; *bp->b_actb = dp; hpibfree(&(sc->sc_dq)); if ((bp = dp) == NULL) mttab[unit].b_active = 0; else mtustart(unit); } /* * The Utah code had a bug which meant that the driver was unable to read. * "rw" was initialized to bp->b_flags & B_READ before "bp" was initialized. * -- ajv@comp.vuw.ac.nz */ void mtgo(unit) register int unit; { register struct mt_softc *sc = &mt_softc[unit]; register struct buf *bp; int rw; dlog(LOG_DEBUG, "mt%d go\n", unit); bp = mttab[unit].b_actf; rw = bp->b_flags & B_READ; hpibgo(sc->sc_hpibno, sc->sc_slave, rw ? MTT_READ : MTL_WRITE, bp->b_un.b_addr, bp->b_bcount, rw, rw != 0); } mtintr(unit) register int unit; { register struct mt_softc *sc = &mt_softc[unit]; register struct buf *bp, *dp; register int i; u_char cmdbuf[4]; bp = mttab[unit].b_actf; if (bp == NULL) { log(LOG_ERR, "mt%d intr: bp == NULL\n", unit); return; } dlog(LOG_DEBUG, "mt%d intr\n", unit); /* * Some operation completed. Read status bytes and report errors. * Clear EOF flags here `cause they're set once on specific conditions * below when a command succeeds. * A DSJ of 2 always means keep waiting. If the command was READ * (and we're in data DMA phase) stop data transfer first. */ sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF); if ((bp->b_flags & (B_CMD|B_READ)) == B_READ && !(sc->sc_flags & (MTF_IO | MTF_STATTIMEO | MTF_DSJTIMEO))){ cmdbuf[0] = MTE_STOP; (void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD,cmdbuf,1); } switch (mtreaddsj(unit, 0)) { case 0: break; case 1: /* * If we're in the middle of a READ/WRITE and have yet to * start the data transfer, a DSJ of one should terminate it. */ sc->sc_flags &= ~MTF_IO; break; case 2: (void) hpibawait(sc->sc_hpibno); return; case -2: /* * -2 means that the drive failed to respond quickly enough * to the request for DSJ. It's probably just "busy" figuring * it out and will know in a little bit... */ timeout(spl_mtintr, (void *)unit, hz >> 5); return; default: log(LOG_ERR, "mt%d intr: can't get drive stat\n", unit); goto error; } if (sc->sc_stat1 & (SR1_ERR | SR1_REJECT)) { i = sc->sc_stat4 & SR4_ERCLMASK; log(LOG_ERR, "mt%d: %s error, retry %d, SR2/3 %x/%x, code %d\n", unit, i == SR4_DEVICE ? "device" : (i == SR4_PROTOCOL ? "protocol" : (i == SR4_SELFTEST ? "selftest" : "unknown")), sc->sc_stat4 & SR4_RETRYMASK, sc->sc_stat2, sc->sc_stat3, sc->sc_stat5); if ((bp->b_flags & B_CMD) && bp->b_cmd == MTRESET) untimeout(spl_mtintr, (void *)unit); if (sc->sc_stat3 & SR3_POWERUP) sc->sc_flags &= MTF_OPEN | MTF_EXISTS; goto error; } /* * Report and clear any soft errors. */ if (sc->sc_stat1 & SR1_SOFTERR) { log(LOG_WARNING, "mt%d: soft error, retry %d\n", unit, sc->sc_stat4 & SR4_RETRYMASK); sc->sc_stat1 &= ~SR1_SOFTERR; } /* * We've initiated a read or write, but haven't actually started to * DMA the data yet. At this point, the drive's ready. */ if (sc->sc_flags & MTF_IO) { sc->sc_flags &= ~MTF_IO; if (hpibustart(sc->sc_hpibno)) mtgo(unit); return; } /* * Check for End Of Tape - we're allowed to hit EOT and then write (or * read) one more record. If we get here and have not already hit EOT, * return ENOSPC to inform the process that it's hit it. If we get * here and HAVE already hit EOT, don't allow any more operations that * move the tape forward. */ if (sc->sc_stat1 & SR1_EOT) { if (sc->sc_flags & MTF_ATEOT) sc->sc_flags |= MTF_PASTEOT; else { bp->b_flags |= B_ERROR; bp->b_error = ENOSPC; sc->sc_flags |= MTF_ATEOT; } } /* * If a motion command was being executed, check for Tape Marks. * If we were doing data, make sure we got the right amount, and * check for hitting tape marks on reads. */ if (bp->b_flags & B_CMD) { if (sc->sc_stat1 & SR1_EOF) { if (bp->b_cmd == MTFSR) sc->sc_flags |= MTF_HITEOF; if (bp->b_cmd == MTBSR) sc->sc_flags |= MTF_HITBOF; } if (bp->b_cmd == MTRESET) { untimeout(spl_mtintr, (void *)unit); sc->sc_flags |= MTF_ALIVE; } } else { i = hpibrecv(sc->sc_hpibno, sc->sc_slave, MTT_BCNT, cmdbuf, 2); if (i != 2) { log(LOG_ERR, "mt%d intr: can't get xfer length\n"); goto error; } i = (int) *((u_short *) cmdbuf); if (i <= bp->b_bcount) { if (i == 0) sc->sc_flags |= MTF_HITEOF; bp->b_resid = bp->b_bcount - i; dlog(LOG_DEBUG, "mt%d intr: bcount %d, resid %d\n", unit, bp->b_bcount, bp->b_resid); } else { tprintf(sc->sc_ttyp, "mt%d: record (%d) larger than wanted (%d)\n", unit, i, bp->b_bcount); error: sc->sc_flags &= ~MTF_IO; bp->b_error = EIO; bp->b_flags |= B_ERROR; } } /* * The operation is completely done. * Let the drive know with an END command. */ cmdbuf[0] = MTE_COMPLETE | MTE_IDLE; (void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD, cmdbuf, 1); bp->b_flags &= ~B_CMD; iodone(bp); if (dp = bp->b_actf) dp->b_actb = bp->b_actb; else mttab[unit].b_actb = bp->b_actb; *bp->b_actb = dp; hpibfree(&(sc->sc_dq)); #if 0 if (bp /*mttab[unit].b_actf*/ == NULL) #else if (mttab[unit].b_actf == NULL) #endif mttab[unit].b_active = 0; else mtustart(unit); } mtread(dev, uio) dev_t dev; struct uio *uio; { return(physio(mtstrategy, &mtbuf[UNIT(dev)], dev, B_READ, minphys, uio)); } mtwrite(dev, uio) dev_t dev; struct uio *uio; { return(physio(mtstrategy, &mtbuf[UNIT(dev)], dev, B_WRITE, minphys, uio)); } mtioctl(dev, cmd, data, flag) dev_t dev; u_long cmd; caddr_t data; int flag; { register struct mtop *op; int cnt; switch (cmd) { case MTIOCTOP: op = (struct mtop *)data; switch(op->mt_op) { case MTWEOF: case MTFSF: case MTBSR: case MTBSF: case MTFSR: cnt = op->mt_count; break; case MTOFFL: case MTREW: case MTNOP: cnt = 0; break; default: return (EINVAL); } return (mtcommand(dev, op->mt_op, cnt)); case MTIOCGET: break; default: return (EINVAL); } return (0); } /*ARGSUSED*/ mtdump(dev) dev_t dev; { return(ENXIO); } #endif /* NMT > 0 */