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mt.c revision 1.29
      1 /*	$NetBSD: mt.c,v 1.29 2005/06/02 16:25:02 tsutsui Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jason R. Thorpe.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  * 3. All advertising materials mentioning features or use of this software
     19  *    must display the following acknowledgement:
     20  *	This product includes software developed by the NetBSD
     21  *	Foundation, Inc. and its contributors.
     22  * 4. Neither the name of The NetBSD Foundation nor the names of its
     23  *    contributors may be used to endorse or promote products derived
     24  *    from this software without specific prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     36  * POSSIBILITY OF SUCH DAMAGE.
     37  */
     38 
     39 /*
     40  * Copyright (c) 1992, The University of Utah and
     41  * the Computer Systems Laboratory at the University of Utah (CSL).
     42  * All rights reserved.
     43  *
     44  * Permission to use, copy, modify and distribute this software is hereby
     45  * granted provided that (1) source code retains these copyright, permission,
     46  * and disclaimer notices, and (2) redistributions including binaries
     47  * reproduce the notices in supporting documentation, and (3) all advertising
     48  * materials mentioning features or use of this software display the following
     49  * acknowledgement: ``This product includes software developed by the
     50  * Computer Systems Laboratory at the University of Utah.''
     51  *
     52  * THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS
     53  * IS" CONDITION.  THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF
     54  * ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     55  *
     56  * CSL requests users of this software to return to csl-dist (at) cs.utah.edu any
     57  * improvements that they make and grant CSL redistribution rights.
     58  *
     59  *	Utah $Hdr: mt.c 1.8 95/09/12$
     60  */
     61 /*	@(#)mt.c	3.9	90/07/10	mt Xinu
     62  *
     63  * Magnetic tape driver (7974a, 7978a/b, 7979a, 7980a, 7980xc)
     64  * Original version contributed by Mt. Xinu.
     65  * Modified for 4.4BSD by Mark Davies and Andrew Vignaux, Department of
     66  * Computer Science, Victoria University of Wellington
     67  */
     68 
     69 #include <sys/cdefs.h>
     70 __KERNEL_RCSID(0, "$NetBSD: mt.c,v 1.29 2005/06/02 16:25:02 tsutsui Exp $");
     71 
     72 #include <sys/param.h>
     73 #include <sys/systm.h>
     74 #include <sys/callout.h>
     75 #include <sys/buf.h>
     76 #include <sys/bufq.h>
     77 #include <sys/ioctl.h>
     78 #include <sys/mtio.h>
     79 #include <sys/file.h>
     80 #include <sys/proc.h>
     81 #include <sys/errno.h>
     82 #include <sys/syslog.h>
     83 #include <sys/tty.h>
     84 #include <sys/kernel.h>
     85 #include <sys/tprintf.h>
     86 #include <sys/device.h>
     87 #include <sys/conf.h>
     88 
     89 #include <hp300/dev/hpibvar.h>
     90 
     91 #include <hp300/dev/mtreg.h>
     92 
     93 #include "ioconf.h"
     94 
     95 static const struct mtinfo {
     96 	u_short	hwid;
     97 	const char *desc;
     98 } mtinfo[] = {
     99 	{ MT7978ID,	"7978"	},
    100 	{ MT7979AID,	"7979A"	},
    101 	{ MT7980ID,	"7980"	},
    102 	{ MT7974AID,	"7974A"	},
    103 };
    104 static const int nmtinfo = sizeof(mtinfo) / sizeof(mtinfo[0]);
    105 
    106 struct	mt_softc {
    107 	struct	device sc_dev;
    108 	struct	callout sc_start_ch;
    109 	struct	callout sc_intr_ch;
    110 	int	sc_hpibno;	/* logical HPIB this slave it attached to */
    111 	int	sc_slave;	/* HPIB slave address (0-6) */
    112 	short	sc_flags;	/* see below */
    113 	u_char	sc_lastdsj;	/* place for DSJ in mtreaddsj() */
    114 	u_char	sc_lastecmd;	/* place for End Command in mtreaddsj() */
    115 	short	sc_recvtimeo;	/* count of hpibsend timeouts to prevent hang */
    116 	short	sc_statindex;	/* index for next sc_stat when MTF_STATTIMEO */
    117 	struct	mt_stat sc_stat;/* status bytes last read from device */
    118 	short	sc_density;	/* current density of tape (mtio.h format) */
    119 	short	sc_type;	/* tape drive model (hardware IDs) */
    120 	struct	hpibqueue sc_hq; /* HPIB device queue member */
    121 	tpr_t	sc_ttyp;
    122 	struct bufq_state sc_tab;/* buf queue */
    123 	int	sc_active;
    124 	struct buf sc_bufstore;	/* XXX buffer storage */
    125 };
    126 
    127 #ifdef DEBUG
    128 int	mtdebug = 0;
    129 #define	dlog	if (mtdebug) log
    130 #else
    131 #define	dlog	if (0) log
    132 #endif
    133 
    134 #define	UNIT(x)		(minor(x) & 3)
    135 
    136 #define B_CMD		B_XXX		/* command buf instead of data */
    137 #define	b_cmd		b_blkno		/* blkno holds cmd when B_CMD */
    138 
    139 static int	mtmatch(struct device *, struct cfdata *, void *);
    140 static void	mtattach(struct device *, struct device *, void *);
    141 
    142 CFATTACH_DECL(mt, sizeof(struct mt_softc),
    143     mtmatch, mtattach, NULL, NULL);
    144 
    145 static dev_type_open(mtopen);
    146 static dev_type_close(mtclose);
    147 static dev_type_read(mtread);
    148 static dev_type_write(mtwrite);
    149 static dev_type_ioctl(mtioctl);
    150 static dev_type_strategy(mtstrategy);
    151 
    152 const struct bdevsw mt_bdevsw = {
    153 	mtopen, mtclose, mtstrategy, mtioctl, nodump, nosize, D_TAPE
    154 };
    155 
    156 const struct cdevsw mt_cdevsw = {
    157 	mtopen, mtclose, mtread, mtwrite, mtioctl,
    158 	nostop, notty, nopoll, nommap, nokqfilter, D_TAPE
    159 };
    160 
    161 static int	mtident(struct mt_softc *, struct hpibbus_attach_args *);
    162 static void	mtustart(struct mt_softc *);
    163 static int	mtreaddsj(struct mt_softc *, int);
    164 static int	mtcommand(dev_t, int, int);
    165 static void	spl_mtintr(void *);
    166 static void	spl_mtstart(void *);
    167 
    168 static void	mtstart(void *);
    169 static void	mtgo(void *);
    170 static void	mtintr(void *);
    171 
    172 static int
    173 mtmatch(struct device *parent, struct cfdata *match, void *aux)
    174 {
    175 	struct hpibbus_attach_args *ha = aux;
    176 
    177 	return (mtident(NULL, ha));
    178 }
    179 
    180 static void
    181 mtattach(struct device *parent, struct device *self, void *aux)
    182 {
    183 	struct mt_softc *sc = (struct mt_softc *)self;
    184 	struct hpibbus_attach_args *ha = aux;
    185 	int unit, hpibno, slave;
    186 
    187 	if (mtident(sc, ha) == 0) {
    188 		printf("\n%s: impossible!\n", sc->sc_dev.dv_xname);
    189 		return;
    190 	}
    191 
    192 	unit = self->dv_unit;
    193 	hpibno = parent->dv_unit;
    194 	slave = ha->ha_slave;
    195 
    196 	bufq_alloc(&sc->sc_tab, BUFQ_FCFS);
    197 	callout_init(&sc->sc_start_ch);
    198 	callout_init(&sc->sc_intr_ch);
    199 
    200 	sc->sc_hpibno = hpibno;
    201 	sc->sc_slave = slave;
    202 	sc->sc_flags = MTF_EXISTS;
    203 
    204 	/* Initialize hpib job queue entry. */
    205 	sc->sc_hq.hq_softc = sc;
    206 	sc->sc_hq.hq_slave = sc->sc_slave;
    207 	sc->sc_hq.hq_start = mtstart;
    208 	sc->sc_hq.hq_go = mtgo;
    209 	sc->sc_hq.hq_intr = mtintr;
    210 }
    211 
    212 static int
    213 mtident(struct mt_softc *sc, struct hpibbus_attach_args *ha)
    214 {
    215 	int i;
    216 
    217 	for (i = 0; i < nmtinfo; i++) {
    218 		if (ha->ha_id == mtinfo[i].hwid) {
    219 			if (sc != NULL) {
    220 				sc->sc_type = mtinfo[i].hwid;
    221 				printf(": %s tape\n", mtinfo[i].desc);
    222 			}
    223 			return (1);
    224 		}
    225 	}
    226 	return (0);
    227 }
    228 
    229 /*
    230  * Perform a read of "Device Status Jump" register and update the
    231  * status if necessary.  If status is read, the given "ecmd" is also
    232  * performed, unless "ecmd" is zero.  Returns DSJ value, -1 on failure
    233  * and -2 on "temporary" failure.
    234  */
    235 static int
    236 mtreaddsj(struct mt_softc *sc, int ecmd)
    237 {
    238 	int retval;
    239 
    240 	if (sc->sc_flags & MTF_STATTIMEO)
    241 		goto getstats;
    242 	retval = hpibrecv(sc->sc_hpibno,
    243 	    (sc->sc_flags & MTF_DSJTIMEO) ? -1 : sc->sc_slave,
    244 	    MTT_DSJ, &(sc->sc_lastdsj), 1);
    245 	sc->sc_flags &= ~MTF_DSJTIMEO;
    246 	if (retval != 1) {
    247 		dlog(LOG_DEBUG, "%s can't hpibrecv DSJ",
    248 		    sc->sc_dev.dv_xname);
    249 		if (sc->sc_recvtimeo == 0)
    250 			sc->sc_recvtimeo = hz;
    251 		if (--sc->sc_recvtimeo == 0)
    252 			return (-1);
    253 		if (retval == 0)
    254 			sc->sc_flags |= MTF_DSJTIMEO;
    255 		return (-2);
    256 	}
    257 	sc->sc_recvtimeo = 0;
    258 	sc->sc_statindex = 0;
    259 	dlog(LOG_DEBUG, "%s readdsj: 0x%x", sc->sc_dev.dv_xname,
    260 	    sc->sc_lastdsj);
    261 	sc->sc_lastecmd = ecmd;
    262 	switch (sc->sc_lastdsj) {
    263 	    case 0:
    264 		if (ecmd & MTE_DSJ_FORCE)
    265 			break;
    266 		return (0);
    267 
    268 	    case 2:
    269 		sc->sc_lastecmd = MTE_COMPLETE;
    270 	    case 1:
    271 		break;
    272 
    273 	    default:
    274 		log(LOG_ERR, "%s readdsj: DSJ 0x%x\n", sc->sc_dev.dv_xname,
    275 		    sc->sc_lastdsj);
    276 		return (-1);
    277 	}
    278     getstats:
    279 	retval = hpibrecv(sc->sc_hpibno,
    280 	    (sc->sc_flags & MTF_STATCONT) ? -1 : sc->sc_slave,
    281 	    MTT_STAT, ((char *)&(sc->sc_stat)) + sc->sc_statindex,
    282 	    sizeof(sc->sc_stat) - sc->sc_statindex);
    283 	sc->sc_flags &= ~(MTF_STATTIMEO | MTF_STATCONT);
    284 	if (retval != sizeof(sc->sc_stat) - sc->sc_statindex) {
    285 		if (sc->sc_recvtimeo == 0)
    286 			sc->sc_recvtimeo = hz;
    287 		if (--sc->sc_recvtimeo != 0) {
    288 			if (retval >= 0) {
    289 				sc->sc_statindex += retval;
    290 				sc->sc_flags |= MTF_STATCONT;
    291 			}
    292 			sc->sc_flags |= MTF_STATTIMEO;
    293 			return (-2);
    294 		}
    295 		log(LOG_ERR, "%s readdsj: can't read status",
    296 		    sc->sc_dev.dv_xname);
    297 		return (-1);
    298 	}
    299 	sc->sc_recvtimeo = 0;
    300 	sc->sc_statindex = 0;
    301 	dlog(LOG_DEBUG, "%s readdsj: status is %x %x %x %x %x %x",
    302 	    sc->sc_dev.dv_xname,
    303 	    sc->sc_stat1, sc->sc_stat2, sc->sc_stat3,
    304 	    sc->sc_stat4, sc->sc_stat5, sc->sc_stat6);
    305 	if (sc->sc_lastecmd)
    306 		(void) hpibsend(sc->sc_hpibno, sc->sc_slave,
    307 		    MTL_ECMD, &(sc->sc_lastecmd), 1);
    308 	return ((int) sc->sc_lastdsj);
    309 }
    310 
    311 static int
    312 mtopen(dev_t dev, int flag, int mode, struct proc *p)
    313 {
    314 	int unit = UNIT(dev);
    315 	struct mt_softc *sc;
    316 	int req_den;
    317 	int error;
    318 
    319 	if (unit >= mt_cd.cd_ndevs ||
    320 	    (sc = mt_cd.cd_devs[unit]) == NULL ||
    321 	    (sc->sc_flags & MTF_EXISTS) == 0)
    322 		return (ENXIO);
    323 
    324 	dlog(LOG_DEBUG, "%s open: flags 0x%x", sc->sc_dev.dv_xname,
    325 	    sc->sc_flags);
    326 	if (sc->sc_flags & MTF_OPEN)
    327 		return (EBUSY);
    328 	sc->sc_flags |= MTF_OPEN;
    329 	sc->sc_ttyp = tprintf_open(p);
    330 	if ((sc->sc_flags & MTF_ALIVE) == 0) {
    331 		error = mtcommand(dev, MTRESET, 0);
    332 		if (error != 0 || (sc->sc_flags & MTF_ALIVE) == 0)
    333 			goto errout;
    334 		if ((sc->sc_stat1 & (SR1_BOT | SR1_ONLINE)) == SR1_ONLINE)
    335 			(void) mtcommand(dev, MTREW, 0);
    336 	}
    337 	for (;;) {
    338 		if ((error = mtcommand(dev, MTNOP, 0)) != 0)
    339 			goto errout;
    340 		if (!(sc->sc_flags & MTF_REW))
    341 			break;
    342 		if (tsleep((caddr_t) &lbolt, PCATCH | (PZERO + 1),
    343 		    "mt", 0) != 0) {
    344 			error = EINTR;
    345 			goto errout;
    346 		}
    347 	}
    348 	if ((flag & FWRITE) && (sc->sc_stat1 & SR1_RO)) {
    349 		error = EROFS;
    350 		goto errout;
    351 	}
    352 	if (!(sc->sc_stat1 & SR1_ONLINE)) {
    353 		uprintf("%s: not online\n", sc->sc_dev.dv_xname);
    354 		error = EIO;
    355 		goto errout;
    356 	}
    357 	/*
    358 	 * Select density:
    359 	 *  - find out what density the drive is set to
    360 	 *	(i.e. the density of the current tape)
    361 	 *  - if we are going to write
    362 	 *    - if we're not at the beginning of the tape
    363 	 *      - complain if we want to change densities
    364 	 *    - otherwise, select the mtcommand to set the density
    365 	 *
    366 	 * If the drive doesn't support it then don't change the recorded
    367 	 * density.
    368 	 *
    369 	 * The original MOREbsd code had these additional conditions
    370 	 * for the mid-tape change
    371 	 *
    372 	 *	req_den != T_BADBPI &&
    373 	 *	sc->sc_density != T_6250BPI
    374 	 *
    375 	 * which suggests that it would be possible to write multiple
    376 	 * densities if req_den == T_BAD_BPI or the current tape
    377 	 * density was 6250.  Testing of our 7980 suggests that the
    378 	 * device cannot change densities mid-tape.
    379 	 *
    380 	 * ajv (at) comp.vuw.ac.nz
    381 	 */
    382 	sc->sc_density = (sc->sc_stat2 & SR2_6250) ? T_6250BPI : (
    383 			 (sc->sc_stat3 & SR3_1600) ? T_1600BPI : (
    384 			 (sc->sc_stat3 & SR3_800) ? T_800BPI : -1));
    385 	req_den = (dev & T_DENSEL);
    386 
    387 	if (flag & FWRITE) {
    388 		if (!(sc->sc_stat1 & SR1_BOT)) {
    389 			if (sc->sc_density != req_den) {
    390 				uprintf("%s: can't change density mid-tape\n",
    391 				    sc->sc_dev.dv_xname);
    392 				error = EIO;
    393 				goto errout;
    394 			}
    395 		}
    396 		else {
    397 			int mtset_density =
    398 			    (req_den == T_800BPI  ? MTSET800BPI : (
    399 			     req_den == T_1600BPI ? MTSET1600BPI : (
    400 			     req_den == T_6250BPI ? MTSET6250BPI : (
    401 			     sc->sc_type == MT7980ID
    402 						  ? MTSET6250DC
    403 						  : MTSET6250BPI))));
    404 			if (mtcommand(dev, mtset_density, 0) == 0)
    405 				sc->sc_density = req_den;
    406 		}
    407 	}
    408 	return (0);
    409 errout:
    410 	sc->sc_flags &= ~MTF_OPEN;
    411 	return (error);
    412 }
    413 
    414 static int
    415 mtclose(dev_t dev, int flag, int fmt, struct proc *p)
    416 {
    417 	struct mt_softc *sc = mt_cd.cd_devs[UNIT(dev)];
    418 
    419 	if (sc->sc_flags & MTF_WRT) {
    420 		(void) mtcommand(dev, MTWEOF, 2);
    421 		(void) mtcommand(dev, MTBSF, 0);
    422 	}
    423 	if ((minor(dev) & T_NOREWIND) == 0)
    424 		(void) mtcommand(dev, MTREW, 0);
    425 	sc->sc_flags &= ~MTF_OPEN;
    426 	tprintf_close(sc->sc_ttyp);
    427 	return (0);
    428 }
    429 
    430 static int
    431 mtcommand(dev_t dev, int cmd, int cnt)
    432 {
    433 	struct mt_softc *sc = mt_cd.cd_devs[UNIT(dev)];
    434 	struct buf *bp = &sc->sc_bufstore;
    435 	int error = 0;
    436 
    437 #if 1
    438 	if (bp->b_flags & B_BUSY)
    439 		return (EBUSY);
    440 #endif
    441 	bp->b_cmd = cmd;
    442 	bp->b_dev = dev;
    443 	do {
    444 		bp->b_flags = B_BUSY | B_CMD;
    445 		mtstrategy(bp);
    446 		biowait(bp);
    447 		if (bp->b_flags & B_ERROR) {
    448 			error = (int) (unsigned) bp->b_error;
    449 			break;
    450 		}
    451 	} while (--cnt > 0);
    452 #if 0
    453 	bp->b_flags = 0 /*&= ~B_BUSY*/;
    454 #else
    455 	bp->b_flags &= ~B_BUSY;
    456 #endif
    457 	return (error);
    458 }
    459 
    460 /*
    461  * Only thing to check here is for legal record lengths (writes only).
    462  */
    463 static void
    464 mtstrategy(struct buf *bp)
    465 {
    466 	struct mt_softc *sc;
    467 	int unit;
    468 	int s;
    469 
    470 	unit = UNIT(bp->b_dev);
    471 	sc = mt_cd.cd_devs[unit];
    472 	dlog(LOG_DEBUG, "%s strategy", sc->sc_dev.dv_xname);
    473 	if ((bp->b_flags & (B_CMD | B_READ)) == 0) {
    474 #define WRITE_BITS_IGNORED	8
    475 #if 0
    476 		if (bp->b_bcount & ((1 << WRITE_BITS_IGNORED) - 1)) {
    477 			tprintf(sc->sc_ttyp,
    478 				"%s: write record must be multiple of %d\n",
    479 				sc->sc_dev.dv_xname, 1 << WRITE_BITS_IGNORED);
    480 			goto error;
    481 		}
    482 #endif
    483 		s = 16 * 1024;
    484 		if (sc->sc_stat2 & SR2_LONGREC) {
    485 			switch (sc->sc_density) {
    486 			    case T_1600BPI:
    487 				s = 32 * 1024;
    488 				break;
    489 
    490 			    case T_6250BPI:
    491 			    case T_BADBPI:
    492 				s = 60 * 1024;
    493 				break;
    494 			}
    495 		}
    496 		if (bp->b_bcount > s) {
    497 			tprintf(sc->sc_ttyp,
    498 				"%s: write record (%d) too big: limit (%d)\n",
    499 				sc->sc_dev.dv_xname, bp->b_bcount, s);
    500 #if 0 /* XXX see above */
    501 	    error:
    502 #endif
    503 			bp->b_flags |= B_ERROR;
    504 			bp->b_error = EIO;
    505 			biodone(bp);
    506 			return;
    507 		}
    508 	}
    509 	s = splbio();
    510 	BUFQ_PUT(&sc->sc_tab, bp);
    511 	if (sc->sc_active == 0) {
    512 		sc->sc_active = 1;
    513 		mtustart(sc);
    514 	}
    515 	splx(s);
    516 }
    517 
    518 static void
    519 mtustart(struct mt_softc *sc)
    520 {
    521 
    522 	dlog(LOG_DEBUG, "%s ustart", sc->sc_dev.dv_xname);
    523 	if (hpibreq(sc->sc_dev.dv_parent, &sc->sc_hq))
    524 		mtstart(sc);
    525 }
    526 
    527 static void
    528 spl_mtintr(void *arg)
    529 {
    530 	struct mt_softc *sc = arg;
    531 	int s = splbio();
    532 
    533 	hpibppclear(sc->sc_hpibno);
    534 	mtintr(sc);
    535 	splx(s);
    536 }
    537 
    538 static void
    539 spl_mtstart(void *arg)
    540 {
    541 	int s = splbio();
    542 
    543 	mtstart(arg);
    544 	splx(s);
    545 }
    546 
    547 static void
    548 mtstart(void *arg)
    549 {
    550 	struct mt_softc *sc = arg;
    551 	struct buf *bp;
    552 	short	cmdcount = 1;
    553 	u_char	cmdbuf[2];
    554 
    555 	dlog(LOG_DEBUG, "%s start", sc->sc_dev.dv_xname);
    556 	sc->sc_flags &= ~MTF_WRT;
    557 	bp = BUFQ_PEEK(&sc->sc_tab);
    558 	if ((sc->sc_flags & MTF_ALIVE) == 0 &&
    559 	    ((bp->b_flags & B_CMD) == 0 || bp->b_cmd != MTRESET))
    560 		goto fatalerror;
    561 
    562 	if (sc->sc_flags & MTF_REW) {
    563 		if (!hpibpptest(sc->sc_hpibno, sc->sc_slave))
    564 			goto stillrew;
    565 		switch (mtreaddsj(sc, MTE_DSJ_FORCE|MTE_COMPLETE|MTE_IDLE)) {
    566 		    case 0:
    567 		    case 1:
    568 		stillrew:
    569 			if ((sc->sc_stat1 & SR1_BOT) ||
    570 			    !(sc->sc_stat1 & SR1_ONLINE)) {
    571 				sc->sc_flags &= ~MTF_REW;
    572 				break;
    573 			}
    574 		    case -2:
    575 			/*
    576 			 * -2 means "timeout" reading DSJ, which is probably
    577 			 * temporary.  This is considered OK when doing a NOP,
    578 			 * but not otherwise.
    579 			 */
    580 			if (sc->sc_flags & (MTF_DSJTIMEO | MTF_STATTIMEO)) {
    581 				callout_reset(&sc->sc_start_ch, hz >> 5,
    582 				    spl_mtstart, sc);
    583 				return;
    584 			}
    585 		    case 2:
    586 			if (bp->b_cmd != MTNOP || !(bp->b_flags & B_CMD)) {
    587 				bp->b_error = EBUSY;
    588 				goto errdone;
    589 			}
    590 			goto done;
    591 
    592 		    default:
    593 			goto fatalerror;
    594 		}
    595 	}
    596 	if (bp->b_flags & B_CMD) {
    597 		if (sc->sc_flags & MTF_PASTEOT) {
    598 			switch(bp->b_cmd) {
    599 			    case MTFSF:
    600 			    case MTWEOF:
    601 			    case MTFSR:
    602 				bp->b_error = ENOSPC;
    603 				goto errdone;
    604 
    605 			    case MTBSF:
    606 			    case MTOFFL:
    607 			    case MTBSR:
    608 			    case MTREW:
    609 				sc->sc_flags &= ~(MTF_PASTEOT | MTF_ATEOT);
    610 				break;
    611 			}
    612 		}
    613 		switch(bp->b_cmd) {
    614 		    case MTFSF:
    615 			if (sc->sc_flags & MTF_HITEOF)
    616 				goto done;
    617 			cmdbuf[0] = MTTC_FSF;
    618 			break;
    619 
    620 		    case MTBSF:
    621 			if (sc->sc_flags & MTF_HITBOF)
    622 				goto done;
    623 			cmdbuf[0] = MTTC_BSF;
    624 			break;
    625 
    626 		    case MTOFFL:
    627 			sc->sc_flags |= MTF_REW;
    628 			cmdbuf[0] = MTTC_REWOFF;
    629 			break;
    630 
    631 		    case MTWEOF:
    632 			cmdbuf[0] = MTTC_WFM;
    633 			break;
    634 
    635 		    case MTBSR:
    636 			cmdbuf[0] = MTTC_BSR;
    637 			break;
    638 
    639 		    case MTFSR:
    640 			cmdbuf[0] = MTTC_FSR;
    641 			break;
    642 
    643 		    case MTREW:
    644 			sc->sc_flags |= MTF_REW;
    645 			cmdbuf[0] = MTTC_REW;
    646 			break;
    647 
    648 		    case MTNOP:
    649 			/*
    650 			 * NOP is supposed to set status bits.
    651 			 * Force readdsj to do it.
    652 			 */
    653 			switch (mtreaddsj(sc,
    654 			  MTE_DSJ_FORCE | MTE_COMPLETE | MTE_IDLE)) {
    655 			    default:
    656 				goto done;
    657 
    658 			    case -1:
    659 				/*
    660 				 * If this fails, perform a device clear
    661 				 * to fix any protocol problems and (most
    662 				 * likely) get the status.
    663 				 */
    664 				bp->b_cmd = MTRESET;
    665 				break;
    666 
    667 			    case -2:
    668 				callout_reset(&sc->sc_start_ch, hz >> 5,
    669 				    spl_mtstart, sc);
    670 				return;
    671 			}
    672 
    673 		    case MTRESET:
    674 			/*
    675 			 * 1) selected device clear (send with "-2" secondary)
    676 			 * 2) set timeout, then wait for "service request"
    677 			 * 3) interrupt will read DSJ (and END COMPLETE-IDLE)
    678 			 */
    679 			if (hpibsend(sc->sc_hpibno, sc->sc_slave, -2, NULL, 0)){
    680 				log(LOG_ERR, "%s can't reset",
    681 				    sc->sc_dev.dv_xname);
    682 				goto fatalerror;
    683 			}
    684 			callout_reset(&sc->sc_intr_ch, 4 * hz, spl_mtintr, sc);
    685 			hpibawait(sc->sc_hpibno);
    686 			return;
    687 
    688 		    case MTSET800BPI:
    689 			cmdbuf[0] = MTTC_800;
    690 			break;
    691 
    692 		    case MTSET1600BPI:
    693 			cmdbuf[0] = MTTC_1600;
    694 			break;
    695 
    696 		    case MTSET6250BPI:
    697 			cmdbuf[0] = MTTC_6250;
    698 			break;
    699 
    700 		    case MTSET6250DC:
    701 			cmdbuf[0] = MTTC_DC6250;
    702 			break;
    703 		}
    704 	} else {
    705 		if (sc->sc_flags & MTF_PASTEOT) {
    706 			bp->b_error = ENOSPC;
    707 			goto errdone;
    708 		}
    709 		if (bp->b_flags & B_READ) {
    710 			sc->sc_flags |= MTF_IO;
    711 			cmdbuf[0] = MTTC_READ;
    712 		} else {
    713 			sc->sc_flags |= MTF_WRT | MTF_IO;
    714 			cmdbuf[0] = MTTC_WRITE;
    715 			cmdbuf[1] = (bp->b_bcount + ((1 << WRITE_BITS_IGNORED) - 1)) >> WRITE_BITS_IGNORED;
    716 			cmdcount = 2;
    717 		}
    718 	}
    719 	if (hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_TCMD, cmdbuf, cmdcount)
    720 	    == cmdcount) {
    721 		if (sc->sc_flags & MTF_REW)
    722 			goto done;
    723 		hpibawait(sc->sc_hpibno);
    724 		return;
    725 	}
    726 fatalerror:
    727 	/*
    728 	 * If anything fails, the drive is probably hosed, so mark it not
    729 	 * "ALIVE" (but it EXISTS and is OPEN or we wouldn't be here, and
    730 	 * if, last we heard, it was REWinding, remember that).
    731 	 */
    732 	sc->sc_flags &= MTF_EXISTS | MTF_OPEN | MTF_REW;
    733 	bp->b_error = EIO;
    734 errdone:
    735 	bp->b_flags |= B_ERROR;
    736 done:
    737 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
    738 	(void)BUFQ_GET(&sc->sc_tab);
    739 	biodone(bp);
    740 	hpibfree(sc->sc_dev.dv_parent, &sc->sc_hq);
    741 	if ((bp = BUFQ_PEEK(&sc->sc_tab)) == NULL)
    742 		sc->sc_active = 0;
    743 	else
    744 		mtustart(sc);
    745 }
    746 
    747 /*
    748  * The Utah code had a bug which meant that the driver was unable to read.
    749  * "rw" was initialized to bp->b_flags & B_READ before "bp" was initialized.
    750  *   -- ajv (at) comp.vuw.ac.nz
    751  */
    752 static void
    753 mtgo(void *arg)
    754 {
    755 	struct mt_softc *sc = arg;
    756 	struct buf *bp;
    757 	int rw;
    758 
    759 	dlog(LOG_DEBUG, "%s go", sc->sc_dev.dv_xname);
    760 	bp = BUFQ_PEEK(&sc->sc_tab);
    761 	rw = bp->b_flags & B_READ;
    762 	hpibgo(sc->sc_hpibno, sc->sc_slave, rw ? MTT_READ : MTL_WRITE,
    763 	    bp->b_data, bp->b_bcount, rw, rw != 0);
    764 }
    765 
    766 static void
    767 mtintr(void *arg)
    768 {
    769 	struct mt_softc *sc = arg;
    770 	struct buf *bp;
    771 	int i;
    772 	u_char cmdbuf[4];
    773 
    774 	bp = BUFQ_PEEK(&sc->sc_tab);
    775 	if (bp == NULL) {
    776 		log(LOG_ERR, "%s intr: bp == NULL", sc->sc_dev.dv_xname);
    777 		return;
    778 	}
    779 
    780 	dlog(LOG_DEBUG, "%s intr", sc->sc_dev.dv_xname);
    781 
    782 	/*
    783 	 * Some operation completed.  Read status bytes and report errors.
    784 	 * Clear EOF flags here `cause they're set once on specific conditions
    785 	 * below when a command succeeds.
    786 	 * A DSJ of 2 always means keep waiting.  If the command was READ
    787 	 * (and we're in data DMA phase) stop data transfer first.
    788 	 */
    789 	sc->sc_flags &= ~(MTF_HITEOF | MTF_HITBOF);
    790 	if ((bp->b_flags & (B_CMD|B_READ)) == B_READ &&
    791 	    !(sc->sc_flags & (MTF_IO | MTF_STATTIMEO | MTF_DSJTIMEO))){
    792 		cmdbuf[0] = MTE_STOP;
    793 		(void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD,cmdbuf,1);
    794 	}
    795 	switch (mtreaddsj(sc, 0)) {
    796 	    case 0:
    797 		break;
    798 
    799 	    case 1:
    800 		/*
    801 		 * If we're in the middle of a READ/WRITE and have yet to
    802 		 * start the data transfer, a DSJ of one should terminate it.
    803 		 */
    804 		sc->sc_flags &= ~MTF_IO;
    805 		break;
    806 
    807 	    case 2:
    808 		(void) hpibawait(sc->sc_hpibno);
    809 		return;
    810 
    811 	    case -2:
    812 		/*
    813 		 * -2 means that the drive failed to respond quickly enough
    814 		 * to the request for DSJ.  It's probably just "busy" figuring
    815 		 * it out and will know in a little bit...
    816 		 */
    817 		callout_reset(&sc->sc_intr_ch, hz >> 5, spl_mtintr, sc);
    818 		return;
    819 
    820 	    default:
    821 		log(LOG_ERR, "%s intr: can't get drive stat",
    822 		    sc->sc_dev.dv_xname);
    823 		goto error;
    824 	}
    825 	if (sc->sc_stat1 & (SR1_ERR | SR1_REJECT)) {
    826 		i = sc->sc_stat4 & SR4_ERCLMASK;
    827 		log(LOG_ERR, "%s: %s error, retry %d, SR2/3 %x/%x, code %d",
    828 			sc->sc_dev.dv_xname, i == SR4_DEVICE ? "device" :
    829 			(i == SR4_PROTOCOL ? "protocol" :
    830 			(i == SR4_SELFTEST ? "selftest" : "unknown")),
    831 			sc->sc_stat4 & SR4_RETRYMASK, sc->sc_stat2,
    832 			sc->sc_stat3, sc->sc_stat5);
    833 
    834 		if ((bp->b_flags & B_CMD) && bp->b_cmd == MTRESET)
    835 			callout_stop(&sc->sc_intr_ch);
    836 		if (sc->sc_stat3 & SR3_POWERUP)
    837 			sc->sc_flags &= MTF_OPEN | MTF_EXISTS;
    838 		goto error;
    839 	}
    840 	/*
    841 	 * Report and clear any soft errors.
    842 	 */
    843 	if (sc->sc_stat1 & SR1_SOFTERR) {
    844 		log(LOG_WARNING, "%s: soft error, retry %d\n",
    845 			sc->sc_dev.dv_xname, sc->sc_stat4 & SR4_RETRYMASK);
    846 		sc->sc_stat1 &= ~SR1_SOFTERR;
    847 	}
    848 	/*
    849 	 * We've initiated a read or write, but haven't actually started to
    850 	 * DMA the data yet.  At this point, the drive's ready.
    851 	 */
    852 	if (sc->sc_flags & MTF_IO) {
    853 		sc->sc_flags &= ~MTF_IO;
    854 		if (hpibustart(sc->sc_hpibno))
    855 			mtgo(sc);
    856 		return;
    857 	}
    858 	/*
    859 	 * Check for End Of Tape - we're allowed to hit EOT and then write (or
    860 	 * read) one more record.  If we get here and have not already hit EOT,
    861 	 * return ENOSPC to inform the process that it's hit it.  If we get
    862 	 * here and HAVE already hit EOT, don't allow any more operations that
    863 	 * move the tape forward.
    864 	 */
    865 	if (sc->sc_stat1 & SR1_EOT) {
    866 		if (sc->sc_flags & MTF_ATEOT)
    867 			sc->sc_flags |= MTF_PASTEOT;
    868 		else {
    869 			bp->b_flags |= B_ERROR;
    870 			bp->b_error = ENOSPC;
    871 			sc->sc_flags |= MTF_ATEOT;
    872 		}
    873 	}
    874 	/*
    875 	 * If a motion command was being executed, check for Tape Marks.
    876 	 * If we were doing data, make sure we got the right amount, and
    877 	 * check for hitting tape marks on reads.
    878 	 */
    879 	if (bp->b_flags & B_CMD) {
    880 		if (sc->sc_stat1 & SR1_EOF) {
    881 			if (bp->b_cmd == MTFSR)
    882 				sc->sc_flags |= MTF_HITEOF;
    883 			if (bp->b_cmd == MTBSR)
    884 				sc->sc_flags |= MTF_HITBOF;
    885 		}
    886 		if (bp->b_cmd == MTRESET) {
    887 			callout_stop(&sc->sc_intr_ch);
    888 			sc->sc_flags |= MTF_ALIVE;
    889 		}
    890 	} else {
    891 		i = hpibrecv(sc->sc_hpibno, sc->sc_slave, MTT_BCNT, cmdbuf, 2);
    892 		if (i != 2) {
    893 			log(LOG_ERR, "%s intr: can't get xfer length\n",
    894 			    sc->sc_dev.dv_xname);
    895 			goto error;
    896 		}
    897 		i = (int) *((u_short *) cmdbuf);
    898 		if (i <= bp->b_bcount) {
    899 			if (i == 0)
    900 				sc->sc_flags |= MTF_HITEOF;
    901 			bp->b_resid = bp->b_bcount - i;
    902 			dlog(LOG_DEBUG, "%s intr: bcount %d, resid %d",
    903 			    sc->sc_dev.dv_xname, bp->b_bcount, bp->b_resid);
    904 		} else {
    905 			tprintf(sc->sc_ttyp,
    906 				"%s: record (%d) larger than wanted (%d)\n",
    907 				sc->sc_dev.dv_xname, i, bp->b_bcount);
    908     error:
    909 			sc->sc_flags &= ~MTF_IO;
    910 			bp->b_error = EIO;
    911 			bp->b_flags |= B_ERROR;
    912 		}
    913 	}
    914 	/*
    915 	 * The operation is completely done.
    916 	 * Let the drive know with an END command.
    917 	 */
    918 	cmdbuf[0] = MTE_COMPLETE | MTE_IDLE;
    919 	(void) hpibsend(sc->sc_hpibno, sc->sc_slave, MTL_ECMD, cmdbuf, 1);
    920 	bp->b_flags &= ~B_CMD;
    921 	(void)BUFQ_GET(&sc->sc_tab);
    922 	biodone(bp);
    923 	hpibfree(sc->sc_dev.dv_parent, &sc->sc_hq);
    924 	if (BUFQ_PEEK(&sc->sc_tab) == NULL)
    925 		sc->sc_active = 0;
    926 	else
    927 		mtustart(sc);
    928 }
    929 
    930 static int
    931 mtread(dev_t dev, struct uio *uio, int flags)
    932 {
    933 	struct mt_softc *sc = mt_cd.cd_devs[UNIT(dev)];
    934 
    935 	return(physio(mtstrategy, &sc->sc_bufstore,
    936 	    dev, B_READ, minphys, uio));
    937 }
    938 
    939 static int
    940 mtwrite(dev_t dev, struct uio *uio, int flags)
    941 {
    942 	struct mt_softc *sc = mt_cd.cd_devs[UNIT(dev)];
    943 
    944 	return(physio(mtstrategy, &sc->sc_bufstore,
    945 	    dev, B_WRITE, minphys, uio));
    946 }
    947 
    948 static int
    949 mtioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
    950 {
    951 	struct mtop *op;
    952 	int cnt;
    953 
    954 	switch (cmd) {
    955 	    case MTIOCTOP:
    956 		op = (struct mtop *)data;
    957 		switch(op->mt_op) {
    958 		    case MTWEOF:
    959 		    case MTFSF:
    960 		    case MTBSR:
    961 		    case MTBSF:
    962 		    case MTFSR:
    963 			cnt = op->mt_count;
    964 			break;
    965 
    966 		    case MTOFFL:
    967 		    case MTREW:
    968 		    case MTNOP:
    969 			cnt = 0;
    970 			break;
    971 
    972 		    default:
    973 			return (EINVAL);
    974 		}
    975 		return (mtcommand(dev, op->mt_op, cnt));
    976 
    977 	    case MTIOCGET:
    978 		break;
    979 
    980 	    default:
    981 		return (EINVAL);
    982 	}
    983 	return (0);
    984 }
    985