summaryrefslogtreecommitdiff
path: root/sys/scsi/scsi_base.c
blob: bdbb1604dd61d485acbf873d004e125b56d333db (plain)
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/*	$OpenBSD: scsi_base.c,v 1.193 2010/08/30 02:47:56 matthew Exp $	*/
/*	$NetBSD: scsi_base.c,v 1.43 1997/04/02 02:29:36 mycroft Exp $	*/

/*
 * Copyright (c) 1994, 1995, 1997 Charles M. Hannum.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Charles M. Hannum.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Originally written by Julian Elischer (julian@dialix.oz.au)
 * Detailed SCSI error printing Copyright 1997 by Matthew Jacob.
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/buf.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <sys/errno.h>
#include <sys/device.h>
#include <sys/proc.h>
#include <sys/pool.h>

#include <scsi/scsi_all.h>
#include <scsi/scsi_disk.h>
#include <scsi/scsiconf.h>

static __inline void asc2ascii(u_int8_t, u_int8_t ascq, char *result,
    size_t len);
int	scsi_xs_error(struct scsi_xfer *);
char   *scsi_decode_sense(struct scsi_sense_data *, int);

void	scsi_xs_sync_done(struct scsi_xfer *);

/* Values for flag parameter to scsi_decode_sense. */
#define	DECODE_SENSE_KEY	1
#define	DECODE_ASC_ASCQ		2
#define DECODE_SKSV		3

struct pool		scsi_xfer_pool;
struct pool		scsi_plug_pool;

struct scsi_plug {
	struct workq_task	wqt;
	int			target;
	int			lun;
	int			how;
};

void	scsi_plug_probe(void *, void *);
void	scsi_plug_detach(void *, void *);

struct scsi_xfer *	scsi_xs_io(struct scsi_link *, void *, int);

int			scsi_ioh_pending(struct scsi_iopool *);
struct scsi_iohandler *	scsi_ioh_deq(struct scsi_iopool *);
void			scsi_ioh_runqueue(struct scsi_iopool *);

void			scsi_xsh_runqueue(struct scsi_link *);
void			scsi_xsh_ioh(void *, void *);

int			scsi_link_open(struct scsi_link *);
void			scsi_link_close(struct scsi_link *);

int			scsi_sem_enter(struct mutex *, u_int *);
int			scsi_sem_leave(struct mutex *, u_int *);

/* ioh/xsh queue state */
#define RUNQ_IDLE	0
#define RUNQ_LINKQ	1
#define RUNQ_POOLQ	2

/* synchronous api for allocating an io. */
struct scsi_io_mover {
	struct mutex mtx;
	void *io;
	u_int done;
};
#define SCSI_IO_MOVER_INITIALIZER { MUTEX_INITIALIZER(IPL_BIO), NULL, 0 }

void scsi_move(struct scsi_io_mover *);
void scsi_move_done(void *, void *);

void scsi_io_get_done(void *, void *);
void scsi_xs_get_done(void *, void *);

/*
 * Called when a scsibus is attached to initialize global data.
 */
void
scsi_init()
{
	static int scsi_init_done;

	if (scsi_init_done)
		return;
	scsi_init_done = 1;

#if defined(SCSI_DELAY) && SCSI_DELAY > 0
	/* Historical. Older buses may need a moment to stabilize. */
	delay(1000000 * SCSI_DELAY);
#endif

	/* Initialize the scsi_xfer pool. */
	pool_init(&scsi_xfer_pool, sizeof(struct scsi_xfer), 0,
	    0, 0, "scxspl", NULL);
	pool_setipl(&scsi_xfer_pool, IPL_BIO);
	/* Initialize the scsi_plug pool */
	pool_init(&scsi_plug_pool, sizeof(struct scsi_plug), 0,
	    0, 0, "scsiplug", NULL);
	pool_setipl(&scsi_plug_pool, IPL_BIO);
}

int
scsi_req_probe(struct scsibus_softc *sc, int target, int lun)
{
	struct scsi_plug *p;

	p = pool_get(&scsi_plug_pool, PR_NOWAIT);
	if (p == NULL)
		return (ENOMEM);

	p->target = target;
	p->lun = lun;

	workq_queue_task(NULL, &p->wqt, 0, scsi_plug_probe, sc, p);

	return (0);
}

int
scsi_req_detach(struct scsibus_softc *sc, int target, int lun, int how)
{
	struct scsi_plug *p;

	p = pool_get(&scsi_plug_pool, PR_NOWAIT);
	if (p == NULL)
		return (ENOMEM);

	p->target = target;
	p->lun = lun;
	p->how = how;

	workq_queue_task(NULL, &p->wqt, 0, scsi_plug_detach, sc, p);

	return (0);
}

void
scsi_plug_probe(void *xsc, void *xp)
{
	struct scsibus_softc *sc = xsc;
	struct scsi_plug *p = xp;

	if (p->lun == -1)
		scsi_probe_target(sc, p->target);
	else
		scsi_probe_lun(sc, p->target, p->lun);

	pool_put(&scsi_plug_pool, p);
}

void
scsi_plug_detach(void *xsc, void *xp)
{
	struct scsibus_softc *sc = xsc;
	struct scsi_plug *p = xp;

	if (p->lun == -1)
		scsi_detach_target(sc, p->target, p->how);
	else
		scsi_detach_lun(sc, p->target, p->lun, p->how);

	pool_put(&scsi_plug_pool, p);
}

int
scsi_sem_enter(struct mutex *mtx, u_int *running)
{
	int rv = 1;

	mtx_enter(mtx);
	(*running)++;
	if ((*running) > 1)
		rv = 0;
	mtx_leave(mtx);

	return (rv);
}

int
scsi_sem_leave(struct mutex *mtx, u_int *running)
{
	int rv = 1;

	mtx_enter(mtx);
	(*running)--;
	if ((*running) > 0)
		rv = 0;
	mtx_leave(mtx);

	return (rv);
}

void
scsi_iopool_init(struct scsi_iopool *iopl, void *iocookie,
    void *(*io_get)(void *), void (*io_put)(void *, void *))
{
	iopl->iocookie = iocookie;
	iopl->io_get = io_get;
	iopl->io_put = io_put;

	TAILQ_INIT(&iopl->queue);
	iopl->running = 0;
	mtx_init(&iopl->mtx, IPL_BIO);
}

void
scsi_iopool_destroy(struct scsi_iopool *iopl)
{
	struct scsi_runq sleepers = TAILQ_HEAD_INITIALIZER(sleepers);
	struct scsi_iohandler *ioh = NULL;

	mtx_enter(&iopl->mtx);
	while ((ioh = TAILQ_FIRST(&iopl->queue)) != NULL) {
		TAILQ_REMOVE(&iopl->queue, ioh, q_entry);
		ioh->q_state = RUNQ_IDLE;

		if (ioh->handler == scsi_io_get_done)
			TAILQ_INSERT_TAIL(&sleepers, ioh, q_entry);
#ifdef DIAGNOSTIC
		else
			panic("scsi_iopool_destroy: scsi_iohandler on pool");
#endif
	}
	mtx_leave(&iopl->mtx);

	while ((ioh = TAILQ_FIRST(&sleepers)) != NULL) {
		TAILQ_REMOVE(&sleepers, ioh, q_entry);
		ioh->handler(ioh->cookie, NULL);
	}
}

void *
scsi_default_get(void *iocookie)
{
	return (iocookie);
}

void
scsi_default_put(void *iocookie, void *io)
{
#ifdef DIAGNOSTIC
	if (iocookie != io)
		panic("unexpected opening returned");
#endif
}

/*
 * public interface to the ioh api.
 */

void
scsi_ioh_set(struct scsi_iohandler *ioh, struct scsi_iopool *iopl,
    void (*handler)(void *, void *), void *cookie)
{
	ioh->q_state = RUNQ_IDLE;
	ioh->pool = iopl;
	ioh->handler = handler;
	ioh->cookie = cookie;
}

void
scsi_ioh_add(struct scsi_iohandler *ioh)
{
	struct scsi_iopool *iopl = ioh->pool;

	mtx_enter(&iopl->mtx);
	switch (ioh->q_state) {
	case RUNQ_IDLE:
		TAILQ_INSERT_TAIL(&iopl->queue, ioh, q_entry);
		ioh->q_state = RUNQ_POOLQ;
		break;
#ifdef DIAGNOSTIC
	case RUNQ_POOLQ:
		break;
	default:
		panic("scsi_ioh_add: unexpected state %u", ioh->q_state);
#endif
	}
	mtx_leave(&iopl->mtx);

	/* lets get some io up in the air */
	scsi_ioh_runqueue(iopl);
}

void
scsi_ioh_del(struct scsi_iohandler *ioh)
{
	struct scsi_iopool *iopl = ioh->pool;

	mtx_enter(&iopl->mtx);
	switch (ioh->q_state) {
	case RUNQ_POOLQ:
		TAILQ_REMOVE(&iopl->queue, ioh, q_entry);
		ioh->q_state = RUNQ_IDLE;
		break;
#ifdef DIAGNOSTIC
	case RUNQ_IDLE:
		break;
	default:
		panic("scsi_ioh_del: unexpected state %u", ioh->q_state);
#endif
	}

	mtx_leave(&iopl->mtx);
}

/*
 * internal iopool runqueue handling.
 */

struct scsi_iohandler *
scsi_ioh_deq(struct scsi_iopool *iopl)
{
	struct scsi_iohandler *ioh = NULL;

	mtx_enter(&iopl->mtx);
	ioh = TAILQ_FIRST(&iopl->queue);
	if (ioh != NULL) {
		TAILQ_REMOVE(&iopl->queue, ioh, q_entry);
		ioh->q_state = RUNQ_IDLE;
	}
	mtx_leave(&iopl->mtx);

	return (ioh);
}

int
scsi_ioh_pending(struct scsi_iopool *iopl)
{
	int rv;

	mtx_enter(&iopl->mtx);
	rv = !TAILQ_EMPTY(&iopl->queue);
	mtx_leave(&iopl->mtx);

	return (rv);
}

void
scsi_ioh_runqueue(struct scsi_iopool *iopl)
{
	struct scsi_iohandler *ioh;
	void *io;

	if (!scsi_sem_enter(&iopl->mtx, &iopl->running))
		return;
	do {
		while (scsi_ioh_pending(iopl)) {
			io = iopl->io_get(iopl->iocookie);
			if (io == NULL)
				break;

			ioh = scsi_ioh_deq(iopl);
			if (ioh == NULL) {
				iopl->io_put(iopl->iocookie, io);
				break;
			}

			ioh->handler(ioh->cookie, io);
		}
	} while (!scsi_sem_leave(&iopl->mtx, &iopl->running));
}

/*
 * move an io from a runq to a proc thats waiting for an io.
 */

void
scsi_move(struct scsi_io_mover *m)
{
	mtx_enter(&m->mtx);
	while (!m->done)
		msleep(m, &m->mtx, PRIBIO, "scsiiomv", 0);
	mtx_leave(&m->mtx);
}

void
scsi_move_done(void *cookie, void *io)
{
	struct scsi_io_mover *m = cookie;

	mtx_enter(&m->mtx);
	m->io = io;
	m->done = 1;
	wakeup_one(m);
	mtx_leave(&m->mtx);
}

/*
 * synchronous api for allocating an io.
 */

void *
scsi_io_get(struct scsi_iopool *iopl, int flags)
{
	struct scsi_io_mover m = SCSI_IO_MOVER_INITIALIZER;
	struct scsi_iohandler ioh;
	void *io;

	/* try and sneak an io off the backend immediately */
	io = iopl->io_get(iopl->iocookie);
	if (io != NULL)
		return (io);
	else if (ISSET(flags, SCSI_NOSLEEP))
		return (NULL);

	/* otherwise sleep until we get one */
	scsi_ioh_set(&ioh, iopl, scsi_io_get_done, &m);
	scsi_ioh_add(&ioh);
	scsi_move(&m);

	return (m.io);
}

void
scsi_io_get_done(void *cookie, void *io)
{
	scsi_move_done(cookie, io);
}

void
scsi_io_put(struct scsi_iopool *iopl, void *io)
{
	iopl->io_put(iopl->iocookie, io);
	scsi_ioh_runqueue(iopl);
}

/*
 * public interface to the xsh api.
 */

void
scsi_xsh_set(struct scsi_xshandler *xsh, struct scsi_link *link,
    void (*handler)(struct scsi_xfer *))
{
	scsi_ioh_set(&xsh->ioh, link->pool, scsi_xsh_ioh, xsh);

	xsh->link = link;
	xsh->handler = handler;
}

void
scsi_xsh_add(struct scsi_xshandler *xsh)
{
	struct scsi_link *link = xsh->link;

	if (ISSET(link->state, SDEV_S_DYING))
		return;

	mtx_enter(&link->pool->mtx);
	if (xsh->ioh.q_state == RUNQ_IDLE) {
		TAILQ_INSERT_TAIL(&link->queue, &xsh->ioh, q_entry);
		xsh->ioh.q_state = RUNQ_LINKQ;
	}
	mtx_leave(&link->pool->mtx);

	/* lets get some io up in the air */
	scsi_xsh_runqueue(link);
}

void
scsi_xsh_del(struct scsi_xshandler *xsh)
{
	struct scsi_link *link = xsh->link;

	mtx_enter(&link->pool->mtx);
	switch (xsh->ioh.q_state) {
	case RUNQ_IDLE:
		break;
	case RUNQ_LINKQ:
		TAILQ_REMOVE(&link->queue, &xsh->ioh, q_entry);
		break;
	case RUNQ_POOLQ:
		TAILQ_REMOVE(&link->pool->queue, &xsh->ioh, q_entry);
		link->openings++;
		break;
	default:
		panic("unexpected xsh state %u", xsh->ioh.q_state);
	}
	xsh->ioh.q_state = RUNQ_IDLE;
	mtx_leave(&link->pool->mtx);
}

/*
 * internal xs runqueue handling.
 */

void
scsi_xsh_runqueue(struct scsi_link *link)
{
	struct scsi_iohandler *ioh;
	int runq;

	if (!scsi_sem_enter(&link->pool->mtx, &link->running))
		return;
	do {
		runq = 0;

		mtx_enter(&link->pool->mtx);
		while (!ISSET(link->state, SDEV_S_DYING) && link->openings &&
		    ((ioh = TAILQ_FIRST(&link->queue)) != NULL)) {
			link->openings--;

			TAILQ_REMOVE(&link->queue, ioh, q_entry);
			TAILQ_INSERT_TAIL(&link->pool->queue, ioh, q_entry);
			ioh->q_state = RUNQ_POOLQ;

			runq = 1;
		}
		mtx_leave(&link->pool->mtx);

		if (runq)
			scsi_ioh_runqueue(link->pool);
	} while (!scsi_sem_leave(&link->pool->mtx, &link->running));
}

void
scsi_xsh_ioh(void *cookie, void *io)
{
	struct scsi_xshandler *xsh = cookie;
	struct scsi_xfer *xs;

	xs = scsi_xs_io(xsh->link, io, SCSI_NOSLEEP);
	if (xs == NULL) {
		/*
		 * in this situation we should queue things waiting for an
		 * xs and then give them xses when they were supposed be to
		 * returned to the pool.
		 */

		printf("scsi_xfer pool exhausted!\n");
		scsi_xsh_add(xsh);
		return;
	}

	xsh->handler(xs);
}

/*
 * Get a scsi transfer structure for the caller.
 * Go to the iopool backend for an "opening" and then attach an xs to it.
 */

struct scsi_xfer *
scsi_xs_get(struct scsi_link *link, int flags)
{
	struct scsi_xshandler xsh;
	struct scsi_io_mover m = SCSI_IO_MOVER_INITIALIZER;

	struct scsi_iopool *iopl = link->pool;
	void *io;

	if (ISSET(link->state, SDEV_S_DYING))
		return (NULL);

	/* really custom xs handler to avoid scsi_xsh_ioh */
	scsi_ioh_set(&xsh.ioh, iopl, scsi_xs_get_done, &m);
	xsh.link = link;

	if (!scsi_link_open(link)) {
		if (ISSET(flags, SCSI_NOSLEEP))
			return (NULL);

		scsi_xsh_add(&xsh);
		scsi_move(&m);
		if (m.io == NULL)
			return (NULL);

		io = m.io;
	} else if ((io = iopl->io_get(iopl->iocookie)) == NULL) {
		if (ISSET(flags, SCSI_NOSLEEP)) {
			scsi_link_close(link);
			return (NULL);
		}

		scsi_ioh_add(&xsh.ioh);
		scsi_move(&m);
		if (m.io == NULL)
			return (NULL);

		io = m.io;
	}

	return (scsi_xs_io(link, io, flags));
}

void
scsi_xs_get_done(void *cookie, void *io)
{
	scsi_move_done(cookie, io);
}

void
scsi_link_shutdown(struct scsi_link *link)
{
	struct scsi_runq sleepers = TAILQ_HEAD_INITIALIZER(sleepers);
	struct scsi_iopool *iopl = link->pool;
	struct scsi_iohandler *ioh;
	struct scsi_xshandler *xsh;

	mtx_enter(&iopl->mtx);
	while ((ioh = TAILQ_FIRST(&link->queue)) != NULL) {
		TAILQ_REMOVE(&link->queue, ioh, q_entry);
		ioh->q_state = RUNQ_IDLE;

		if (ioh->handler == scsi_xs_get_done)
			TAILQ_INSERT_TAIL(&sleepers, ioh, q_entry);
#ifdef DIAGNOSTIC
		else
			panic("scsi_link_shutdown: scsi_xshandler on link");
#endif
	}

	ioh = TAILQ_FIRST(&iopl->queue);
	while (ioh != NULL) {
		xsh = (struct scsi_xshandler *)ioh;
		ioh = TAILQ_NEXT(ioh, q_entry);

#ifdef DIAGNOSTIC
		if (xsh->ioh.handler == scsi_xsh_ioh &&
		    xsh->link == link)
			panic("scsi_link_shutdown: scsi_xshandler on pool");
#endif

		if (xsh->ioh.handler == scsi_xs_get_done &&
		    xsh->link == link) {
			TAILQ_REMOVE(&iopl->queue, &xsh->ioh, q_entry);
			xsh->ioh.q_state = RUNQ_IDLE;
			link->openings++;

			TAILQ_INSERT_TAIL(&sleepers, &xsh->ioh, q_entry);
		}
	}
	mtx_leave(&iopl->mtx);

	while ((ioh = TAILQ_FIRST(&sleepers)) != NULL) {
		TAILQ_REMOVE(&sleepers, ioh, q_entry);
		ioh->handler(ioh->cookie, NULL);
	}
}

int
scsi_link_open(struct scsi_link *link)
{
	int open = 0;

	mtx_enter(&link->pool->mtx);
	if (link->openings) {
		link->openings--;
		open = 1;
	}
	mtx_leave(&link->pool->mtx);

	return (open);
}

void
scsi_link_close(struct scsi_link *link)
{
	mtx_enter(&link->pool->mtx);
	link->openings++;
	mtx_leave(&link->pool->mtx);

	scsi_xsh_runqueue(link);
}

struct scsi_xfer *
scsi_xs_io(struct scsi_link *link, void *io, int flags)
{
	struct scsi_xfer *xs;

	xs = pool_get(&scsi_xfer_pool, PR_ZERO |
	    (ISSET(flags, SCSI_NOSLEEP) ? PR_NOWAIT : PR_WAITOK));
	if (xs == NULL) {
		scsi_io_put(link->pool, io);
		scsi_link_close(link);
	} else {
		xs->flags = flags;
		xs->sc_link = link;
		xs->retries = SCSI_RETRIES;
		xs->timeout = 10000;
		xs->cmd = &xs->cmdstore;
		xs->io = io;
	}

	return (xs);
}

void
scsi_xs_put(struct scsi_xfer *xs)
{
	struct scsi_link *link = xs->sc_link;
	void *io = xs->io;

	pool_put(&scsi_xfer_pool, xs);

	scsi_io_put(link->pool, io);
	scsi_link_close(link);
}

/*
 * Find out from the device what its capacity is.
 */
daddr64_t
scsi_size(struct scsi_link *sc_link, int flags, u_int32_t *blksize)
{
	struct scsi_read_cap_data_16 *rdcap16;
	struct scsi_read_capacity_16 *cmd;
	struct scsi_read_cap_data *rdcap;
	struct scsi_read_capacity *cmd10;
	struct scsi_xfer *xs;
	daddr64_t max_addr;
	int error;

	if (blksize != NULL)
		*blksize = 0;

	CLR(flags, SCSI_IGNORE_ILLEGAL_REQUEST);

	/*
	 * Start with a READ CAPACITY(10).
	 */
	rdcap = malloc(sizeof(*rdcap), M_TEMP, ((flags & SCSI_NOSLEEP) ?
	    M_NOWAIT : M_WAITOK) | M_ZERO);
	if (rdcap == NULL)
		return (0);

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_IN | SCSI_SILENT);
	if (xs == NULL) {
		free(rdcap, M_TEMP);
		return (0);
	}
	xs->cmdlen = sizeof(*cmd10);
	xs->data = (void *)rdcap;
	xs->datalen = sizeof(*rdcap);
	xs->timeout = 20000;

	cmd10 = (struct scsi_read_capacity *)xs->cmd;
	cmd10->opcode = READ_CAPACITY;

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	if (error) {
		SC_DEBUG(sc_link, SDEV_DB1, ("READ CAPACITY error (%#x)\n",
		    error));
		free(rdcap, M_TEMP);
		return (0);
	}

	max_addr = _4btol(rdcap->addr);
	if (blksize != NULL)
		*blksize = _4btol(rdcap->length);
	free(rdcap, M_TEMP);

	if (SCSISPC(sc_link->inqdata.version) < 3 && max_addr != 0xffffffff)
		goto exit;

	/*
	 * SCSI-3 devices, or devices reporting more than 2^32-1 sectors can
	 * try READ CAPACITY(16).
	 */
	rdcap16 = malloc(sizeof(*rdcap16), M_TEMP, ((flags & SCSI_NOSLEEP) ?
	    M_NOWAIT : M_WAITOK) | M_ZERO);
	if (rdcap16 == NULL)
		goto exit;

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_IN | SCSI_SILENT);
	if (xs == NULL) {
		free(rdcap16, M_TEMP);
		goto exit;
	}
	xs->cmdlen = sizeof(*cmd);
	xs->data = (void *)rdcap16;
	xs->datalen = sizeof(*rdcap16);
	xs->timeout = 20000;

	cmd = (struct scsi_read_capacity_16 *)xs->cmd;
	cmd->opcode = READ_CAPACITY_16;
	cmd->byte2 = SRC16_SERVICE_ACTION;
	_lto4b(sizeof(*rdcap16), cmd->length);

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);
	if (error) {
		SC_DEBUG(sc_link, SDEV_DB1, ("READ CAPACITY 16 error (%#x)\n",
		    error));
		free(rdcap16, M_TEMP);
		goto exit;
	}

	max_addr = _8btol(rdcap16->addr);
	if (blksize != NULL)
		*blksize = _4btol(rdcap16->length);
	/* XXX The other READ CAPACITY(16) info could be stored away. */
	free(rdcap16, M_TEMP);

	return (max_addr + 1);

exit:
	/* Return READ CAPACITY 10 values. */
	if (max_addr != 0xffffffff)
		return (max_addr + 1);
	else if (blksize != NULL)
		*blksize = 0;
	return (0);
}

/*
 * Get scsi driver to send a "are you ready?" command
 */
int
scsi_test_unit_ready(struct scsi_link *sc_link, int retries, int flags)
{
	struct scsi_test_unit_ready *cmd;
	struct scsi_xfer *xs;
	int error;

	xs = scsi_xs_get(sc_link, flags);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->retries = retries;
	xs->timeout = 10000;

	cmd = (struct scsi_test_unit_ready *)xs->cmd;
	cmd->opcode = TEST_UNIT_READY;

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	return (error);
}

/*
 * Do a scsi operation asking a device what it is.
 * Use the scsi_cmd routine in the switch table.
 */
int
scsi_inquire(struct scsi_link *link, struct scsi_inquiry_data *inqbuf,
    int flags)
{
	struct scsi_inquiry *cmd;
	struct scsi_xfer *xs;
	size_t length;
	int error;

	xs = scsi_xs_get(link, flags);
	if (xs == NULL)
		return (EBUSY);

	/*
	 * Ask for only the basic 36 bytes of SCSI2 inquiry information. This
	 * avoids problems with devices that choke trying to supply more.
	 */
	length = SID_INQUIRY_HDR + SID_SCSI2_ALEN;

	cmd = (struct scsi_inquiry *)xs->cmd;
	cmd->opcode = INQUIRY;
	_lto2b(length, cmd->length);

	xs->cmdlen = sizeof(*cmd);

	xs->flags |= SCSI_DATA_IN;
	xs->data = (void *)inqbuf;
	xs->datalen = length;

	bzero(inqbuf, sizeof(*inqbuf));
	memset(&inqbuf->vendor, ' ', sizeof inqbuf->vendor);
	memset(&inqbuf->product, ' ', sizeof inqbuf->product);
	memset(&inqbuf->revision, ' ', sizeof inqbuf->revision);
	memset(&inqbuf->extra, ' ', sizeof inqbuf->extra);

	error = scsi_xs_sync(xs);

	scsi_xs_put(xs);

	return (error);
}

/*
 * Query a VPD inquiry page
 */
int
scsi_inquire_vpd(struct scsi_link *sc_link, void *buf, u_int buflen,
    u_int8_t page, int flags)
{
	struct scsi_inquiry *cmd;
	struct scsi_xfer *xs;
	int error;

	bzero(buf, buflen);

	if (sc_link->flags & SDEV_UMASS)
		return (EJUSTRETURN);

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_IN | SCSI_SILENT);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->data = buf;
	xs->datalen = buflen;
	xs->retries = 2;
	xs->timeout = 10000;

	cmd = (struct scsi_inquiry *)xs->cmd;
	cmd->opcode = INQUIRY;
	cmd->flags = SI_EVPD;
	cmd->pagecode = page;
	_lto2b(buflen, cmd->length);

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	return (error);
}

/*
 * Prevent or allow the user to remove the media
 */
int
scsi_prevent(struct scsi_link *sc_link, int type, int flags)
{
	struct scsi_prevent *cmd;
	struct scsi_xfer *xs;
	int error;

	if (sc_link->quirks & ADEV_NODOORLOCK)
		return (0);

	xs = scsi_xs_get(sc_link, flags);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->retries = 2;
	xs->timeout = 5000;

	cmd = (struct scsi_prevent *)xs->cmd;
	cmd->opcode = PREVENT_ALLOW;
	cmd->how = type;

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	return (error);
}

/*
 * Get scsi driver to send a "start up" command
 */
int
scsi_start(struct scsi_link *sc_link, int type, int flags)
{
	struct scsi_start_stop *cmd;
	struct scsi_xfer *xs;
	int error;

	xs = scsi_xs_get(sc_link, flags);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->retries = 2;
	xs->timeout = (type == SSS_START) ? 30000 : 10000;

	cmd = (struct scsi_start_stop *)xs->cmd;
	cmd->opcode = START_STOP;
	cmd->how = type;

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	return (error);
}

int
scsi_mode_sense(struct scsi_link *sc_link, int byte2, int page,
    struct scsi_mode_header *data, size_t len, int flags, int timeout)
{
	struct scsi_mode_sense *cmd;
	struct scsi_xfer *xs;
	int error;

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_IN);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->data = (void *)data;
	xs->datalen = len;
	xs->timeout = timeout;

	/*
	 * Make sure the sense buffer is clean before we do the mode sense, so
	 * that checks for bogus values of 0 will work in case the mode sense
	 * fails.
	 */
	bzero(data, len);

	cmd = (struct scsi_mode_sense *)xs->cmd;
	cmd->opcode = MODE_SENSE;
	cmd->byte2 = byte2;
	cmd->page = page;

	if (len > 0xff)
		len = 0xff;
	cmd->length = len;

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	SC_DEBUG(sc_link, SDEV_DB2, ("scsi_mode_sense: page %#x, error = %d\n",
	    page, error));

	return (error);
}

int
scsi_mode_sense_big(struct scsi_link *sc_link, int byte2, int page,
    struct scsi_mode_header_big *data, size_t len, int flags, int timeout)
{
	struct scsi_mode_sense_big *cmd;
	struct scsi_xfer *xs;
	int error;

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_IN);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->data = (void *)data;
	xs->datalen = len;
	xs->timeout = timeout;

	/*
	 * Make sure the sense buffer is clean before we do the mode sense, so
	 * that checks for bogus values of 0 will work in case the mode sense
	 * fails.
	 */
	bzero(data, len);

	cmd = (struct scsi_mode_sense_big *)xs->cmd;
	cmd->opcode = MODE_SENSE_BIG;
	cmd->byte2 = byte2;
	cmd->page = page;

	if (len > 0xffff)
		len = 0xffff;
	_lto2b(len, cmd->length);

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	SC_DEBUG(sc_link, SDEV_DB2,
	    ("scsi_mode_sense_big: page %#x, error = %d\n", page, error));

	return (error);
}

void *
scsi_mode_sense_page(struct scsi_mode_header *hdr, const int page_len)
{
	int					total_length, header_length;

	total_length = hdr->data_length + sizeof(hdr->data_length);
	header_length = sizeof(*hdr) + hdr->blk_desc_len;

	if ((total_length - header_length) < page_len)
		return (NULL);

	return ((u_char *)hdr + header_length);
}

void *
scsi_mode_sense_big_page(struct scsi_mode_header_big *hdr, const int page_len)
{
	int					total_length, header_length;

	total_length = _2btol(hdr->data_length) + sizeof(hdr->data_length);
	header_length = sizeof(*hdr) + _2btol(hdr->blk_desc_len);

	if ((total_length - header_length) < page_len)
		return (NULL);

	return ((u_char *)hdr + header_length);
}

int
scsi_do_mode_sense(struct scsi_link *sc_link, int page,
    union scsi_mode_sense_buf *buf, void **page_data, u_int32_t *density,
    u_int64_t *block_count, u_int32_t *block_size, int page_len, int flags,
    int *big)
{
	struct scsi_direct_blk_desc		*direct;
	struct scsi_blk_desc			*general;
	int					error, blk_desc_len, offset;

	*page_data = NULL;

	if (density != NULL)
		*density = 0;
	if (block_count != NULL)
		*block_count = 0;
	if (block_size != NULL)
		*block_size = 0;
	if (big != NULL)
		*big = 0;

	if ((sc_link->flags & SDEV_ATAPI) == 0 ||
	    (sc_link->inqdata.device & SID_TYPE) == T_SEQUENTIAL) {
		/*
		 * Try 6 byte mode sense request first. Some devices don't
		 * distinguish between 6 and 10 byte MODE SENSE commands,
		 * returning 6 byte data for 10 byte requests. ATAPI tape
		 * drives use MODE SENSE (6) even though ATAPI uses 10 byte
		 * everything else. Don't bother with SMS_DBD. Check returned
		 * data length to ensure that at least a header (3 additional
		 * bytes) is returned.
		 */
		error = scsi_mode_sense(sc_link, 0, page, &buf->hdr,
		    sizeof(*buf), flags, 20000);
		if (error == 0) {
			*page_data = scsi_mode_sense_page(&buf->hdr, page_len);
			if (*page_data == NULL) {
				/*
				 * XXX
				 * Page data may be invalid (e.g. all zeros)
				 * but we accept the device's word that this is
				 * the best it can do. Some devices will freak
				 * out if their word is not accepted and 
				 * MODE_SENSE_BIG is attempted.
				 */
				return (0);
			}
			offset = sizeof(struct scsi_mode_header);
			blk_desc_len = buf->hdr.blk_desc_len;
			goto blk_desc;
		}
	}

	/*
	 * Try 10 byte mode sense request. Don't bother with SMS_DBD or
	 * SMS_LLBAA. Bail out if the returned information is less than
	 * a big header in size (6 additional bytes).
	 */
	error = scsi_mode_sense_big(sc_link, 0, page, &buf->hdr_big,
	    sizeof(*buf), flags, 20000);
	if (error != 0)
		return (error);
	if (_2btol(buf->hdr_big.data_length) < 6)
		return (EIO);

	if (big != NULL)
		*big = 1;
	offset = sizeof(struct scsi_mode_header_big);
	*page_data = scsi_mode_sense_big_page(&buf->hdr_big, page_len);
	blk_desc_len = _2btol(buf->hdr_big.blk_desc_len);

blk_desc:
	/* Both scsi_blk_desc and scsi_direct_blk_desc are 8 bytes. */
	if (blk_desc_len == 0 || (blk_desc_len % 8 != 0))
		return (0);

	switch (sc_link->inqdata.device & SID_TYPE) {
	case T_SEQUENTIAL:
		/*
		 * XXX What other device types return general block descriptors?
		 */
		general = (struct scsi_blk_desc *)&buf->buf[offset];
		if (density != NULL)
			*density = general->density;
		if (block_size != NULL)
			*block_size = _3btol(general->blklen);
		if (block_count != NULL)
			*block_count = (u_int64_t)_3btol(general->nblocks);
		break;

	default:
		direct = (struct scsi_direct_blk_desc *)&buf->buf[offset];
		if (density != NULL)
			*density = direct->density;
		if (block_size != NULL)
			*block_size = _3btol(direct->blklen);
		if (block_count != NULL)
			*block_count = (u_int64_t)_4btol(direct->nblocks);
		break;
	}

	return (0);
}

int
scsi_mode_select(struct scsi_link *sc_link, int byte2,
    struct scsi_mode_header *data, int flags, int timeout)
{
	struct scsi_mode_select *cmd;
	struct scsi_xfer *xs;
	u_int32_t len;
	int error;

	len = data->data_length + 1; /* 1 == sizeof(data_length) */

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_OUT);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->data = (void *)data;
	xs->datalen = len;
	xs->timeout = timeout;

	cmd = (struct scsi_mode_select *)xs->cmd;
	cmd->opcode = MODE_SELECT;
	cmd->byte2 = byte2;
	cmd->length = len;

	/* Length is reserved when doing mode select so zero it. */
	data->data_length = 0;

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	SC_DEBUG(sc_link, SDEV_DB2, ("scsi_mode_select: error = %d\n", error));

	return (error);
}

int
scsi_mode_select_big(struct scsi_link *sc_link, int byte2,
    struct scsi_mode_header_big *data, int flags, int timeout)
{
	struct scsi_mode_select_big *cmd;
	struct scsi_xfer *xs;
	u_int32_t len;
	int error;

	len = _2btol(data->data_length) + 2; /* 2 == sizeof data_length */

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_OUT);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->data = (void *)data;
	xs->datalen = len;
	xs->timeout = timeout;

	cmd = (struct scsi_mode_select_big *)xs->cmd;
	cmd->opcode = MODE_SELECT_BIG;
	cmd->byte2 = byte2;
	_lto2b(len, cmd->length);

	/* Length is reserved when doing mode select so zero it. */
	_lto2b(0, data->data_length);

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	SC_DEBUG(sc_link, SDEV_DB2, ("scsi_mode_select_big: error = %d\n",
	    error));

	return (error);
}

int
scsi_report_luns(struct scsi_link *sc_link, int selectreport,
    struct scsi_report_luns_data *data, u_int32_t datalen, int flags,
    int timeout)
{
	struct scsi_report_luns *cmd;
	struct scsi_xfer *xs;
	int error;

	xs = scsi_xs_get(sc_link, flags | SCSI_DATA_IN);
	if (xs == NULL)
		return (ENOMEM);
	xs->cmdlen = sizeof(*cmd);
	xs->data = (void *)data;
	xs->datalen = datalen;
	xs->timeout = timeout;

	bzero(data, datalen);

	cmd = (struct scsi_report_luns *)xs->cmd;
	cmd->opcode = REPORT_LUNS;
	cmd->selectreport = selectreport;
	_lto4b(datalen, cmd->length);

	error = scsi_xs_sync(xs);
	scsi_xs_put(xs);

	SC_DEBUG(sc_link, SDEV_DB2, ("scsi_report_luns: error = %d\n", error));

	return (error);
}

void
scsi_xs_exec(struct scsi_xfer *xs)
{
	xs->error = XS_NOERROR;
	xs->resid = xs->datalen;
	xs->status = 0;
	CLR(xs->flags, ITSDONE);

#ifdef SCSIDEBUG
	if (xs->sc_link->flags & SDEV_DB1) {
		scsi_xs_show(xs);
		if (xs->datalen && (xs->flags & SCSI_DATA_OUT))
			scsi_show_mem(xs->data, min(64, xs->datalen));
	}
#endif

	/* The adapter's scsi_cmd() is responsible for callng scsi_done(). */
	xs->sc_link->adapter->scsi_cmd(xs);
}

/*
 * This routine is called by the adapter when its xs handling is done.
 */
void
scsi_done(struct scsi_xfer *xs)
{
#ifdef SCSIDEBUG
	if (xs->sc_link->flags & SDEV_DB1) {
		if (xs->datalen && (xs->flags & SCSI_DATA_IN))
			scsi_show_mem(xs->data, min(64, xs->datalen));
	}
#endif /* SCSIDEBUG */

	SET(xs->flags, ITSDONE);
	xs->done(xs);
}

int
scsi_xs_sync(struct scsi_xfer *xs)
{
	struct mutex cookie = MUTEX_INITIALIZER(IPL_BIO);
	int error;

#ifdef DIAGNOSTIC
	if (xs->cookie != NULL)
		panic("xs->cookie != NULL in scsi_xs_sync");
	if (xs->done != NULL)
		panic("xs->done != NULL in scsi_xs_sync");
#endif

	/*
	 * If we cant sleep while waiting for completion, get the adapter to
	 * complete it for us.
	 */
	if (ISSET(xs->flags, SCSI_NOSLEEP))
		SET(xs->flags, SCSI_POLL);

	xs->done = scsi_xs_sync_done;

	do {
		xs->cookie = &cookie;

		scsi_xs_exec(xs);

		mtx_enter(&cookie);
		while (xs->cookie != NULL)
			msleep(xs, &cookie, PRIBIO, "syncxs", 0);
		mtx_leave(&cookie);

		error = scsi_xs_error(xs);
	} while (error == ERESTART);

	return (error);
}

void
scsi_xs_sync_done(struct scsi_xfer *xs)
{
	struct mutex *cookie = xs->cookie;

	if (cookie == NULL)
		panic("scsi_done called twice on xs(%p)", xs);

	mtx_enter(cookie);
	xs->cookie = NULL;
	if (!ISSET(xs->flags, SCSI_NOSLEEP))
		wakeup_one(xs);
	mtx_leave(cookie);
}

int
scsi_xs_error(struct scsi_xfer *xs)
{
	int error = EIO;

	SC_DEBUG(xs->sc_link, SDEV_DB3, ("scsi_xs_error,err = 0x%x\n",
	    xs->error));

	if (ISSET(xs->sc_link->state, SDEV_S_DYING))
		return (ENXIO);

	switch (xs->error) {
	case XS_NOERROR:	/* nearly always hit this one */
		error = 0;
		break;

	case XS_SENSE:
	case XS_SHORTSENSE:
#ifdef SCSIDEBUG
		scsi_sense_print_debug(xs);
#endif
		error = xs->sc_link->interpret_sense(xs);
		SC_DEBUG(xs->sc_link, SDEV_DB3,
		    ("scsi_interpret_sense returned %#x\n", error));
		break;

	case XS_NO_CCB:
	case XS_BUSY:
		error = scsi_delay(xs, 1);
		break;

	case XS_TIMEOUT:
	case XS_RESET:
		error = ERESTART;
		break;

	case XS_DRIVER_STUFFUP:
	case XS_SELTIMEOUT:
		break;

	default:
		sc_print_addr(xs->sc_link);
		printf("unknown error category (0x%x) from scsi driver\n",
		    xs->error);
		break;
	}

	if (error == ERESTART && xs->retries-- < 1)
		return (EIO);
	else
		return (error);
}

int
scsi_delay(struct scsi_xfer *xs, int seconds)
{
	switch (xs->flags & (SCSI_POLL | SCSI_NOSLEEP)) {
	case SCSI_POLL:
		delay(1000000 * seconds);
		return (ERESTART);
	case SCSI_NOSLEEP:
		/* Retry the command immediately since we can't delay. */
		return (ERESTART);
	case (SCSI_POLL | SCSI_NOSLEEP):
		/* Invalid combination! */
		return (EIO);
	}

	while (seconds-- > 0) {
		if (tsleep(&lbolt, PRIBIO|PCATCH, "scbusy", 0)) {
			/* Signal == abort xs. */
			return (EIO);
		}
	}

	return (ERESTART);
}

#ifdef SCSIDEBUG
/*
 * Print out sense data details.
 */
void
scsi_sense_print_debug(struct scsi_xfer *xs)
{
	struct scsi_sense_data *sense = &xs->sense;
	struct scsi_link *sc_link = xs->sc_link;

	SC_DEBUG(sc_link, SDEV_DB1,
	    ("code:%#x valid:%d key:%#x ili:%d eom:%d fmark:%d extra:%d\n",
	    sense->error_code & SSD_ERRCODE,
	    sense->error_code & SSD_ERRCODE_VALID ? 1 : 0,
	    sense->flags & SSD_KEY,
	    sense->flags & SSD_ILI ? 1 : 0,
	    sense->flags & SSD_EOM ? 1 : 0,
	    sense->flags & SSD_FILEMARK ? 1 : 0,
	    sense->extra_len));

	if (xs->sc_link->flags & SDEV_DB1)
		scsi_show_mem((u_char *)&xs->sense, sizeof(xs->sense));

	scsi_print_sense(xs);
}
#endif

/*
 * Look at the returned sense and act on the error, determining
 * the unix error number to pass back.  (0 = report no error)
 *
 * THIS IS THE DEFAULT ERROR HANDLER
 */
int
scsi_interpret_sense(struct scsi_xfer *xs)
{
	struct scsi_sense_data			*sense = &xs->sense;
	struct scsi_link			*sc_link = xs->sc_link;
	u_int8_t				serr, skey;
	int					error;

	/* Default sense interpretation. */
	serr = sense->error_code & SSD_ERRCODE;
	if (serr != SSD_ERRCODE_CURRENT && serr != SSD_ERRCODE_DEFERRED)
		skey = 0xff;	/* Invalid value, since key is 4 bit value. */
	else
		skey = sense->flags & SSD_KEY;

	/*
	 * Interpret the key/asc/ascq information where appropriate.
	 */
	error = 0;
	switch (skey) {
	case SKEY_NO_SENSE:
	case SKEY_RECOVERED_ERROR:
		if (xs->resid == xs->datalen)
			xs->resid = 0;	/* not short read */
		break;
	case SKEY_BLANK_CHECK:
	case SKEY_EQUAL:
		break;
	case SKEY_NOT_READY:
		if ((xs->flags & SCSI_IGNORE_NOT_READY) != 0)
			return (0);
		error = EIO;
		if (xs->retries) {
			switch (ASC_ASCQ(sense)) {
			case SENSE_NOT_READY_BECOMING_READY:
			case SENSE_NOT_READY_FORMAT:
			case SENSE_NOT_READY_REBUILD:
			case SENSE_NOT_READY_RECALC:		
			case SENSE_NOT_READY_INPROGRESS:
			case SENSE_NOT_READY_LONGWRITE:
			case SENSE_NOT_READY_SELFTEST:
			case SENSE_NOT_READY_INIT_REQUIRED:
				SC_DEBUG(sc_link, SDEV_DB1,
		    		    ("not ready (ASC_ASCQ == %#x)\n",
				    ASC_ASCQ(sense)));
				return (scsi_delay(xs, 1));
			case SENSE_NOMEDIUM:
			case SENSE_NOMEDIUM_TCLOSED:
			case SENSE_NOMEDIUM_TOPEN:
			case SENSE_NOMEDIUM_LOADABLE:
			case SENSE_NOMEDIUM_AUXMEM:
				sc_link->flags &= ~SDEV_MEDIA_LOADED;
				error = ENOMEDIUM;
				break;
			default:
				break;
			}
		}
		break;
	case SKEY_MEDIUM_ERROR:
		switch (ASC_ASCQ(sense)) {
		case SENSE_NOMEDIUM:
		case SENSE_NOMEDIUM_TCLOSED:
		case SENSE_NOMEDIUM_TOPEN:
		case SENSE_NOMEDIUM_LOADABLE:
		case SENSE_NOMEDIUM_AUXMEM:
			sc_link->flags &= ~SDEV_MEDIA_LOADED;
			error = ENOMEDIUM;
			break;
		case SENSE_BAD_MEDIUM:
		case SENSE_NR_MEDIUM_UNKNOWN_FORMAT:
		case SENSE_NR_MEDIUM_INCOMPATIBLE_FORMAT:
		case SENSE_NW_MEDIUM_UNKNOWN_FORMAT:
		case SENSE_NW_MEDIUM_INCOMPATIBLE_FORMAT:
		case SENSE_NF_MEDIUM_INCOMPATIBLE_FORMAT:
		case SENSE_NW_MEDIUM_AC_MISMATCH:
			error = EMEDIUMTYPE;
			break;
		default:
			error = EIO;
			break;
		}
		break;
	case SKEY_ILLEGAL_REQUEST:
		if ((xs->flags & SCSI_IGNORE_ILLEGAL_REQUEST) != 0)
			return (0);
		if (ASC_ASCQ(sense) == SENSE_MEDIUM_REMOVAL_PREVENTED)
			return(EBUSY);
		error = EINVAL;
		break;
	case SKEY_UNIT_ATTENTION:
		switch (ASC_ASCQ(sense)) {
		case SENSE_POWER_RESET_OR_BUS:
		case SENSE_POWER_ON:
		case SENSE_BUS_RESET:
		case SENSE_BUS_DEVICE_RESET:
		case SENSE_DEVICE_INTERNAL_RESET:
		case SENSE_TSC_CHANGE_SE:
		case SENSE_TSC_CHANGE_LVD:
		case SENSE_IT_NEXUS_LOSS:
			return (scsi_delay(xs, 1));
		default:
			break;
		}
		if ((sc_link->flags & SDEV_REMOVABLE) != 0)
			sc_link->flags &= ~SDEV_MEDIA_LOADED;
		if ((xs->flags & SCSI_IGNORE_MEDIA_CHANGE) != 0 ||
		    /* XXX Should reupload any transient state. */
		    (sc_link->flags & SDEV_REMOVABLE) == 0) {
			return (scsi_delay(xs, 1));
		}
		error = EIO;
		break;
	case SKEY_WRITE_PROTECT:
		error = EROFS;
		break;
	case SKEY_ABORTED_COMMAND:
		error = ERESTART;
		break;
	case SKEY_VOLUME_OVERFLOW:
		error = ENOSPC;
		break;
	case SKEY_HARDWARE_ERROR:
		if (ASC_ASCQ(sense) == SENSE_CARTRIDGE_FAULT)
			return(EMEDIUMTYPE);
		error = EIO;
		break;
	default:
		error = EIO;
		break;
	}

#ifndef SCSIDEBUG
	/* SCSIDEBUG would mean it has already been printed. */
	if (skey && (xs->flags & SCSI_SILENT) == 0)
		scsi_print_sense(xs);
#endif /* SCSIDEBUG */

	return (error);
}

/*
 * Utility routines often used in SCSI stuff
 */


/*
 * Print out the scsi_link structure's address info.
 */
void
sc_print_addr(struct scsi_link *sc_link)
{
	struct device *adapter_device = sc_link->bus->sc_dev.dv_parent;

	printf("%s(%s:%d:%d): ",
	    sc_link->device_softc ?
	    ((struct device *)sc_link->device_softc)->dv_xname : "probe",
	    adapter_device->dv_xname,
	    sc_link->target, sc_link->lun);
}

static const char *sense_keys[16] = {
	"No Additional Sense",
	"Soft Error",
	"Not Ready",
	"Media Error",
	"Hardware Error",
	"Illegal Request",
	"Unit Attention",
	"Write Protected",
	"Blank Check",
	"Vendor Unique",
	"Copy Aborted",
	"Aborted Command",
	"Equal Error",
	"Volume Overflow",
	"Miscompare Error",
	"Reserved"
};

#ifdef SCSITERSE
static __inline void
asc2ascii(u_int8_t asc, u_int8_t ascq, char *result, size_t len)
{
	snprintf(result, len, "ASC 0x%02x ASCQ 0x%02x", asc, ascq);
}
#else
static const struct {
	u_int8_t asc, ascq;
	char *description;
} adesc[] = {
	{ 0x00, 0x00, "No Additional Sense Information" },
	{ 0x00, 0x01, "Filemark Detected" },
	{ 0x00, 0x02, "End-Of-Partition/Medium Detected" },
	{ 0x00, 0x03, "Setmark Detected" },
	{ 0x00, 0x04, "Beginning-Of-Partition/Medium Detected" },
	{ 0x00, 0x05, "End-Of-Data Detected" },
	{ 0x00, 0x06, "I/O Process Terminated" },
	{ 0x00, 0x11, "Audio Play Operation In Progress" },
	{ 0x00, 0x12, "Audio Play Operation Paused" },
	{ 0x00, 0x13, "Audio Play Operation Successfully Completed" },
	{ 0x00, 0x14, "Audio Play Operation Stopped Due to Error" },
	{ 0x00, 0x15, "No Current Audio Status To Return" },
	{ 0x00, 0x16, "Operation In Progress" },
	{ 0x00, 0x17, "Cleaning Requested" },
	{ 0x00, 0x18, "Erase Operation In Progress" },
	{ 0x00, 0x19, "Locate Operation In Progress" },
	{ 0x00, 0x1A, "Rewind Operation In Progress" },
	{ 0x00, 0x1B, "Set Capacity Operation In Progress" },
	{ 0x00, 0x1C, "Verify Operation In Progress" },
	{ 0x01, 0x00, "No Index/Sector Signal" },
	{ 0x02, 0x00, "No Seek Complete" },
	{ 0x03, 0x00, "Peripheral Device Write Fault" },
	{ 0x03, 0x01, "No Write Current" },
	{ 0x03, 0x02, "Excessive Write Errors" },
	{ 0x04, 0x00, "Logical Unit Not Ready, Cause Not Reportable" },
	{ 0x04, 0x01, "Logical Unit Is in Process Of Becoming Ready" },
	{ 0x04, 0x02, "Logical Unit Not Ready, Initialization Command Required" },
	{ 0x04, 0x03, "Logical Unit Not Ready, Manual Intervention Required" },
	{ 0x04, 0x04, "Logical Unit Not Ready, Format In Progress" },
	{ 0x04, 0x05, "Logical Unit Not Ready, Rebuild In Progress" },
	{ 0x04, 0x06, "Logical Unit Not Ready, Recalculation In Progress" },
	{ 0x04, 0x07, "Logical Unit Not Ready, Operation In Progress" },
	{ 0x04, 0x08, "Logical Unit Not Ready, Long Write In Progress" },
	{ 0x04, 0x09, "Logical Unit Not Ready, Self-Test In Progress" },
	{ 0x04, 0x0A, "Logical Unit Not Accessible, Asymmetric Access State Transition" },
	{ 0x04, 0x0B, "Logical Unit Not Accessible, Target Port In Standby State" },
	{ 0x04, 0x0C, "Logical Unit Not Accessible, Target Port In Unavailable State" },
	{ 0x04, 0x10, "Logical Unit Not Ready, Auxiliary Memory Not Accessible" },
	{ 0x04, 0x11, "Logical Unit Not Ready, Notify (Enable Spinup) Required" },
	{ 0x05, 0x00, "Logical Unit Does Not Respond To Selection" },
	{ 0x06, 0x00, "No Reference Position Found" },
	{ 0x07, 0x00, "Multiple Peripheral Devices Selected" },
	{ 0x08, 0x00, "Logical Unit Communication Failure" },
	{ 0x08, 0x01, "Logical Unit Communication Timeout" },
	{ 0x08, 0x02, "Logical Unit Communication Parity Error" },
	{ 0x08, 0x03, "Logical Unit Communication CRC Error (ULTRA-DMA/32)" },
	{ 0x08, 0x04, "Unreachable Copy Target" },
	{ 0x09, 0x00, "Track Following Error" },
	{ 0x09, 0x01, "Tracking Servo Failure" },
	{ 0x09, 0x02, "Focus Servo Failure" },
	{ 0x09, 0x03, "Spindle Servo Failure" },
	{ 0x09, 0x04, "Head Select Fault" },
	{ 0x0A, 0x00, "Error Log Overflow" },
	{ 0x0B, 0x00, "Warning" },
	{ 0x0B, 0x01, "Warning - Specified Temperature Exceeded" },
	{ 0x0B, 0x02, "Warning - Enclosure Degraded" },
	{ 0x0C, 0x00, "Write Error" },
	{ 0x0C, 0x01, "Write Error Recovered with Auto Reallocation" },
	{ 0x0C, 0x02, "Write Error - Auto Reallocate Failed" },
	{ 0x0C, 0x03, "Write Error - Recommend Reassignment" },
	{ 0x0C, 0x04, "Compression Check Miscompare Error" },
	{ 0x0C, 0x05, "Data Expansion Occurred During Compression" },
	{ 0x0C, 0x06, "Block Not Compressible" },
	{ 0x0C, 0x07, "Write Error - Recovery Needed" },
	{ 0x0C, 0x08, "Write Error - Recovery Failed" },
	{ 0x0C, 0x09, "Write Error - Loss Of Streaming" },
	{ 0x0C, 0x0A, "Write Error - Padding Blocks Added" },
	{ 0x0C, 0x0B, "Auxiliary Memory Write Error" },
	{ 0x0C, 0x0C, "Write Error - Unexpected Unsolicited Data" },
	{ 0x0C, 0x0D, "Write Error - Not Enough Unsolicited Data" },
	{ 0x0D, 0x00, "Error Detected By Third Party Temporary Initiator" },
	{ 0x0D, 0x01, "Third Party Device Failure" },
	{ 0x0D, 0x02, "Copy Target Device Not Reachable" },
	{ 0x0D, 0x03, "Incorrect Copy Target Device Type" },
	{ 0x0D, 0x04, "Copy Target Device Data Underrun" },
	{ 0x0D, 0x05, "Copy Target Device Data Overrun" },
	{ 0x0E, 0x00, "Invalid Information Unit" },
	{ 0x0E, 0x01, "Information Unit Too Short" },
	{ 0x0E, 0x02, "Information Unit Too Long" },
	{ 0x10, 0x00, "ID CRC Or ECC Error" },
	{ 0x11, 0x00, "Unrecovered Read Error" },
	{ 0x11, 0x01, "Read Retries Exhausted" },
	{ 0x11, 0x02, "Error Too Long To Correct" },
	{ 0x11, 0x03, "Multiple Read Errors" },
	{ 0x11, 0x04, "Unrecovered Read Error - Auto Reallocate Failed" },
	{ 0x11, 0x05, "L-EC Uncorrectable Error" },
	{ 0x11, 0x06, "CIRC Unrecovered Error" },
	{ 0x11, 0x07, "Data Resynchronization Error" },
	{ 0x11, 0x08, "Incomplete Block Read" },
	{ 0x11, 0x09, "No Gap Found" },
	{ 0x11, 0x0A, "Miscorrected Error" },
	{ 0x11, 0x0B, "Uncorrected Read Error - Recommend Reassignment" },
	{ 0x11, 0x0C, "Uncorrected Read Error - Recommend Rewrite The Data" },
	{ 0x11, 0x0D, "De-Compression CRC Error" },
	{ 0x11, 0x0E, "Cannot Decompress Using Declared Algorithm" },
	{ 0x11, 0x0F, "Error Reading UPC/EAN Number" },
	{ 0x11, 0x10, "Error Reading ISRC Number" },
	{ 0x11, 0x11, "Read Error - Loss Of Streaming" },
	{ 0x11, 0x12, "Auxiliary Memory Read Error" },
	{ 0x11, 0x13, "Read Error - Failed Retransmission Request" },
	{ 0x12, 0x00, "Address Mark Not Found for ID Field" },
	{ 0x13, 0x00, "Address Mark Not Found for Data Field" },
	{ 0x14, 0x00, "Recorded Entity Not Found" },
	{ 0x14, 0x01, "Record Not Found" },
	{ 0x14, 0x02, "Filemark or Setmark Not Found" },
	{ 0x14, 0x03, "End-Of-Data Not Found" },
	{ 0x14, 0x04, "Block Sequence Error" },
	{ 0x14, 0x05, "Record Not Found - Recommend Reassignment" },
	{ 0x14, 0x06, "Record Not Found - Data Auto-Reallocated" },
	{ 0x14, 0x07, "Locate Operation Failure" },
	{ 0x15, 0x00, "Random Positioning Error" },
	{ 0x15, 0x01, "Mechanical Positioning Error" },
	{ 0x15, 0x02, "Positioning Error Detected By Read of Medium" },
	{ 0x16, 0x00, "Data Synchronization Mark Error" },
	{ 0x16, 0x01, "Data Sync Error - Data Rewritten" },
	{ 0x16, 0x02, "Data Sync Error - Recommend Rewrite" },
	{ 0x16, 0x03, "Data Sync Error - Data Auto-Reallocated" },
	{ 0x16, 0x04, "Data Sync Error - Recommend Reassignment" },
	{ 0x17, 0x00, "Recovered Data With No Error Correction Applied" },
	{ 0x17, 0x01, "Recovered Data With Retries" },
	{ 0x17, 0x02, "Recovered Data With Positive Head Offset" },
	{ 0x17, 0x03, "Recovered Data With Negative Head Offset" },
	{ 0x17, 0x04, "Recovered Data With Retries and/or CIRC Applied" },
	{ 0x17, 0x05, "Recovered Data Using Previous Sector ID" },
	{ 0x17, 0x06, "Recovered Data Without ECC - Data Auto-Reallocated" },
	{ 0x17, 0x07, "Recovered Data Without ECC - Recommend Reassignment" },
	{ 0x17, 0x08, "Recovered Data Without ECC - Recommend Rewrite" },
	{ 0x17, 0x09, "Recovered Data Without ECC - Data Rewritten" },
	{ 0x18, 0x00, "Recovered Data With Error Correction Applied" },
	{ 0x18, 0x01, "Recovered Data With Error Correction & Retries Applied" },
	{ 0x18, 0x02, "Recovered Data - Data Auto-Reallocated" },
	{ 0x18, 0x03, "Recovered Data With CIRC" },
	{ 0x18, 0x04, "Recovered Data With L-EC" },
	{ 0x18, 0x05, "Recovered Data - Recommend Reassignment" },
	{ 0x18, 0x06, "Recovered Data - Recommend Rewrite" },
	{ 0x18, 0x07, "Recovered Data With ECC - Data Rewritten" },
	{ 0x18, 0x08, "Recovered Data With Linking" },
	{ 0x19, 0x00, "Defect List Error" },
	{ 0x19, 0x01, "Defect List Not Available" },
	{ 0x19, 0x02, "Defect List Error in Primary List" },
	{ 0x19, 0x03, "Defect List Error in Grown List" },
	{ 0x1A, 0x00, "Parameter List Length Error" },
	{ 0x1B, 0x00, "Synchronous Data Transfer Error" },
	{ 0x1C, 0x00, "Defect List Not Found" },
	{ 0x1C, 0x01, "Primary Defect List Not Found" },
	{ 0x1C, 0x02, "Grown Defect List Not Found" },
	{ 0x1D, 0x00, "Miscompare During Verify Operation" },
	{ 0x1E, 0x00, "Recovered ID with ECC" },
	{ 0x1F, 0x00, "Partial Defect List Transfer" },
	{ 0x20, 0x00, "Invalid Command Operation Code" },
	{ 0x20, 0x01, "Access Denied - Initiator Pending-Enrolled" },
	{ 0x20, 0x02, "Access Denied - No Access rights" },
	{ 0x20, 0x03, "Access Denied - Invalid Mgmt ID Key" },
	{ 0x20, 0x04, "Illegal Command While In Write Capable State" },
	{ 0x20, 0x05, "Obsolete" },
	{ 0x20, 0x06, "Illegal Command While In Explicit Address Mode" },
	{ 0x20, 0x07, "Illegal Command While In Implicit Address Mode" },
	{ 0x20, 0x08, "Access Denied - Enrollment Conflict" },
	{ 0x20, 0x09, "Access Denied - Invalid LU Identifier" },
	{ 0x20, 0x0A, "Access Denied - Invalid Proxy Token" },
	{ 0x20, 0x0B, "Access Denied - ACL LUN Conflict" },
	{ 0x21, 0x00, "Logical Block Address Out of Range" },
	{ 0x21, 0x01, "Invalid Element Address" },
	{ 0x21, 0x02, "Invalid Address For Write" },
	{ 0x22, 0x00, "Illegal Function (Should 20 00, 24 00, or 26 00)" },
	{ 0x24, 0x00, "Illegal Field in CDB" },
	{ 0x24, 0x01, "CDB Decryption Error" },
	{ 0x24, 0x02, "Obsolete" },
	{ 0x24, 0x03, "Obsolete" },
	{ 0x24, 0x04, "Security Audit Value Frozen" },
	{ 0x24, 0x05, "Security Working Key Frozen" },
	{ 0x24, 0x06, "Nonce Not Unique" },
	{ 0x24, 0x07, "Nonce Timestamp Out Of Range" },
	{ 0x25, 0x00, "Logical Unit Not Supported" },
	{ 0x26, 0x00, "Invalid Field In Parameter List" },
	{ 0x26, 0x01, "Parameter Not Supported" },
	{ 0x26, 0x02, "Parameter Value Invalid" },
	{ 0x26, 0x03, "Threshold Parameters Not Supported" },
	{ 0x26, 0x04, "Invalid Release Of Persistent Reservation" },
	{ 0x26, 0x05, "Data Decryption Error" },
	{ 0x26, 0x06, "Too Many Target Descriptors" },
	{ 0x26, 0x07, "Unsupported Target Descriptor Type Code" },
	{ 0x26, 0x08, "Too Many Segment Descriptors" },
	{ 0x26, 0x09, "Unsupported Segment Descriptor Type Code" },
	{ 0x26, 0x0A, "Unexpected Inexact Segment" },
	{ 0x26, 0x0B, "Inline Data Length Exceeded" },
	{ 0x26, 0x0C, "Invalid Operation For Copy Source Or Destination" },
	{ 0x26, 0x0D, "Copy Segment Granularity Violation" },
	{ 0x26, 0x0E, "Invalid Parameter While Port Is Enabled" },
	{ 0x27, 0x00, "Write Protected" },
	{ 0x27, 0x01, "Hardware Write Protected" },
	{ 0x27, 0x02, "Logical Unit Software Write Protected" },
	{ 0x27, 0x03, "Associated Write Protect" },
	{ 0x27, 0x04, "Persistent Write Protect" },
	{ 0x27, 0x05, "Permanent Write Protect" },
	{ 0x27, 0x06, "Conditional Write Protect" },
	{ 0x28, 0x00, "Not Ready To Ready Transition (Medium May Have Changed)" },
	{ 0x28, 0x01, "Import Or Export Element Accessed" },
	{ 0x29, 0x00, "Power On, Reset, or Bus Device Reset Occurred" },
	{ 0x29, 0x01, "Power On Occurred" },
	{ 0x29, 0x02, "SCSI Bus Reset Occurred" },
	{ 0x29, 0x03, "Bus Device Reset Function Occurred" },
	{ 0x29, 0x04, "Device Internal Reset" },
	{ 0x29, 0x05, "Transceiver Mode Changed to Single Ended" },
	{ 0x29, 0x06, "Transceiver Mode Changed to LVD" },
	{ 0x29, 0x07, "I_T Nexus Loss Occurred" },
	{ 0x2A, 0x00, "Parameters Changed" },
	{ 0x2A, 0x01, "Mode Parameters Changed" },
	{ 0x2A, 0x02, "Log Parameters Changed" },
	{ 0x2A, 0x03, "Reservations Preempted" },
	{ 0x2A, 0x04, "Reservations Released" },
	{ 0x2A, 0x05, "Registrations Preempted" },
	{ 0x2A, 0x06, "Asymmetric Access State Changed" },
	{ 0x2A, 0x07, "Implicit Asymmetric Access State Transition Failed" },
	{ 0x2B, 0x00, "Copy Cannot Execute Since Host Cannot Disconnect" },
	{ 0x2C, 0x00, "Command Sequence Error" },
	{ 0x2C, 0x01, "Too Many Windows Specified" },
	{ 0x2C, 0x02, "Invalid Combination of Windows Specified" },
	{ 0x2C, 0x03, "Current Program Area Is Not Empty" },
	{ 0x2C, 0x04, "Current Program Area Is Empty" },
	{ 0x2C, 0x05, "Illegal Power Condition Request" },
	{ 0x2C, 0x06, "Persistent Prevent Conflict" },
	{ 0x2C, 0x07, "Previous Busy Status" },
	{ 0x2C, 0x08, "Previous Task Set Full Status" },
	{ 0x2C, 0x09, "Previous Reservation Conflict Status" },
	{ 0x2C, 0x0A, "Partition Or Collection Contains User Objects" },
	{ 0x2D, 0x00, "Overwrite Error On Update In Place" },
	{ 0x2E, 0x00, "Insufficient Time For Operation" },
	{ 0x2F, 0x00, "Commands Cleared By Another Initiator" },
	{ 0x30, 0x00, "Incompatible Medium Installed" },
	{ 0x30, 0x01, "Cannot Read Medium - Unknown Format" },
	{ 0x30, 0x02, "Cannot Read Medium - Incompatible Format" },
	{ 0x30, 0x03, "Cleaning Cartridge Installed" },
	{ 0x30, 0x04, "Cannot Write Medium - Unknown Format" },
	{ 0x30, 0x05, "Cannot Write Medium - Incompatible Format" },
	{ 0x30, 0x06, "Cannot Format Medium - Incompatible Medium" },
	{ 0x30, 0x07, "Cleaning Failure" },
	{ 0x30, 0x08, "Cannot Write - Application Code Mismatch" },
	{ 0x30, 0x09, "Current Session Not Fixated For Append" },
	{ 0x30, 0x0A, "Cleaning Request Rejected" },
	{ 0x30, 0x10, "Medium Not Formatted" },
	{ 0x31, 0x00, "Medium Format Corrupted" },
	{ 0x31, 0x01, "Format Command Failed" },
	{ 0x32, 0x00, "No Defect Spare Location Available" },
	{ 0x32, 0x01, "Defect List Update Failure" },
	{ 0x33, 0x00, "Tape Length Error" },
	{ 0x34, 0x00, "Enclosure Failure" },
	{ 0x35, 0x00, "Enclosure Services Failure" },
	{ 0x35, 0x01, "Unsupported Enclosure Function" },
	{ 0x35, 0x02, "Enclosure Services Unavailable" },
	{ 0x35, 0x03, "Enclosure Services Transfer Failure" },
	{ 0x35, 0x04, "Enclosure Services Transfer Refused" },
	{ 0x36, 0x00, "Ribbon, Ink, or Toner Failure" },
	{ 0x37, 0x00, "Rounded Parameter" },
	{ 0x38, 0x00, "Event Status Notification" },
	{ 0x38, 0x02, "ESN - Power Management Class Event" },
	{ 0x38, 0x04, "ESN - Media Class Event" },
	{ 0x38, 0x06, "ESN - Device Busy Class Event" },
	{ 0x39, 0x00, "Saving Parameters Not Supported" },
	{ 0x3A, 0x00, "Medium Not Present" },
	{ 0x3A, 0x01, "Medium Not Present - Tray Closed" },
	{ 0x3A, 0x02, "Medium Not Present - Tray Open" },
	{ 0x3A, 0x03, "Medium Not Present - Loadable" },
	{ 0x3A, 0x04, "Medium Not Present - Medium Auxiliary Memory Accessible" },
	{ 0x3B, 0x00, "Sequential Positioning Error" },
	{ 0x3B, 0x01, "Tape Position Error At Beginning-of-Medium" },
	{ 0x3B, 0x02, "Tape Position Error At End-of-Medium" },
	{ 0x3B, 0x03, "Tape or Electronic Vertical Forms Unit Not Ready" },
	{ 0x3B, 0x04, "Slew Failure" },
	{ 0x3B, 0x05, "Paper Jam" },
	{ 0x3B, 0x06, "Failed To Sense Top-Of-Form" },
	{ 0x3B, 0x07, "Failed To Sense Bottom-Of-Form" },
	{ 0x3B, 0x08, "Reposition Error" },
	{ 0x3B, 0x09, "Read Past End Of Medium" },
	{ 0x3B, 0x0A, "Read Past Beginning Of Medium" },
	{ 0x3B, 0x0B, "Position Past End Of Medium" },
	{ 0x3B, 0x0C, "Position Past Beginning Of Medium" },
	{ 0x3B, 0x0D, "Medium Destination Element Full" },
	{ 0x3B, 0x0E, "Medium Source Element Empty" },
	{ 0x3B, 0x0F, "End Of Medium Reached" },
	{ 0x3B, 0x11, "Medium Magazine Not Accessible" },
	{ 0x3B, 0x12, "Medium Magazine Removed" },
	{ 0x3B, 0x13, "Medium Magazine Inserted" },
	{ 0x3B, 0x14, "Medium Magazine Locked" },
	{ 0x3B, 0x15, "Medium Magazine Unlocked" },
	{ 0x3B, 0x16, "Mechanical Positioning Or Changer Error" },
	{ 0x3D, 0x00, "Invalid Bits In IDENTIFY Message" },
	{ 0x3E, 0x00, "Logical Unit Has Not Self-Configured Yet" },
	{ 0x3E, 0x01, "Logical Unit Failure" },
	{ 0x3E, 0x02, "Timeout On Logical Unit" },
	{ 0x3E, 0x03, "Logical Unit Failed Self-Test" },
	{ 0x3E, 0x04, "Logical Unit Unable To Update Self-Test Log" },
	{ 0x3F, 0x00, "Target Operating Conditions Have Changed" },
	{ 0x3F, 0x01, "Microcode Has Changed" },
	{ 0x3F, 0x02, "Changed Operating Definition" },
	{ 0x3F, 0x03, "INQUIRY Data Has Changed" },
	{ 0x3F, 0x04, "component Device Attached" },
	{ 0x3F, 0x05, "Device Identifier Changed" },
	{ 0x3F, 0x06, "Redundancy Group Created Or Modified" },
	{ 0x3F, 0x07, "Redundancy Group Deleted" },
	{ 0x3F, 0x08, "Spare Created Or Modified" },
	{ 0x3F, 0x09, "Spare Deleted" },
	{ 0x3F, 0x0A, "Volume Set Created Or Modified" },
	{ 0x3F, 0x0B, "Volume Set Deleted" },
	{ 0x3F, 0x0C, "Volume Set Deassigned" },
	{ 0x3F, 0x0D, "Volume Set Reassigned" },
	{ 0x3F, 0x0E, "Reported LUNs Data Has Changed" },
	{ 0x3F, 0x0F, "Echo Buffer Overwritten" },
	{ 0x3F, 0x10, "Medium Loadable" },
	{ 0x3F, 0x11, "Medium Auxiliary Memory Accessible" },
	{ 0x40, 0x00, "RAM FAILURE (Should Use 40 NN)" },
	/*
	 * ASC 0x40 also has an ASCQ range from 0x80 to 0xFF.
	 * 0x40 0xNN DIAGNOSTIC FAILURE ON COMPONENT NN
	 */
	{ 0x41, 0x00, "Data Path FAILURE (Should Use 40 NN)" },
	{ 0x42, 0x00, "Power-On or Self-Test FAILURE (Should Use 40 NN)" },
	{ 0x43, 0x00, "Message Error" },
	{ 0x44, 0x00, "Internal Target Failure" },
	{ 0x45, 0x00, "Select Or Reselect Failure" },
	{ 0x46, 0x00, "Unsuccessful Soft Reset" },
	{ 0x47, 0x00, "SCSI Parity Error" },
	{ 0x47, 0x01, "Data Phase CRC Error Detected" },
	{ 0x47, 0x02, "SCSI Parity Error Detected During ST Data Phase" },
	{ 0x47, 0x03, "Information Unit iuCRC Error Detected" },
	{ 0x47, 0x04, "Asynchronous Information Protection Error Detected" },
	{ 0x47, 0x05, "Protocol Service CRC Error" },
	{ 0x47, 0x7F, "Some Commands Cleared By iSCSI Protocol Event" },
	{ 0x48, 0x00, "Initiator Detected Error Message Received" },
	{ 0x49, 0x00, "Invalid Message Error" },
	{ 0x4A, 0x00, "Command Phase Error" },
	{ 0x4B, 0x00, "Data Phase Error" },
	{ 0x4B, 0x01, "Invalid Target Port Transfer Tag Received" },
	{ 0x4B, 0x02, "Too Much Write Data" },
	{ 0x4B, 0x03, "ACK/NAK Timeout" },
	{ 0x4B, 0x04, "NAK Received" },
	{ 0x4B, 0x05, "Data Offset Error" },
	{ 0x4B, 0x06, "Initiator Response Timeout" },
	{ 0x4C, 0x00, "Logical Unit Failed Self-Configuration" },
	/*
	 * ASC 0x4D has an ASCQ range from 0x00 to 0xFF.
	 * 0x4D 0xNN TAGGED OVERLAPPED COMMANDS (NN = TASK TAG)
	 */
	{ 0x4E, 0x00, "Overlapped Commands Attempted" },
	{ 0x50, 0x00, "Write Append Error" },
	{ 0x50, 0x01, "Write Append Position Error" },
	{ 0x50, 0x02, "Position Error Related To Timing" },
	{ 0x51, 0x00, "Erase Failure" },
	{ 0x51, 0x01, "Erase Failure - Incomplete Erase Operation Detected" },
	{ 0x52, 0x00, "Cartridge Fault" },
	{ 0x53, 0x00, "Media Load or Eject Failed" },
	{ 0x53, 0x01, "Unload Tape Failure" },
	{ 0x53, 0x02, "Medium Removal Prevented" },
	{ 0x54, 0x00, "SCSI To Host System Interface Failure" },
	{ 0x55, 0x00, "System Resource Failure" },
	{ 0x55, 0x01, "System Buffer Full" },
	{ 0x55, 0x02, "Insufficient Reservation Resources" },
	{ 0x55, 0x03, "Insufficient Resources" },
	{ 0x55, 0x04, "Insufficient Registration Resources" },
	{ 0x55, 0x05, "Insufficient Access Control Resources" },
	{ 0x55, 0x06, "Auxiliary Memory Out Of Space" },
	{ 0x57, 0x00, "Unable To Recover Table-Of-Contents" },
	{ 0x58, 0x00, "Generation Does Not Exist" },
	{ 0x59, 0x00, "Updated Block Read" },
	{ 0x5A, 0x00, "Operator Request or State Change Input" },
	{ 0x5A, 0x01, "Operator Medium Removal Requested" },
	{ 0x5A, 0x02, "Operator Selected Write Protect" },
	{ 0x5A, 0x03, "Operator Selected Write Permit" },
	{ 0x5B, 0x00, "Log Exception" },
	{ 0x5B, 0x01, "Threshold Condition Met" },
	{ 0x5B, 0x02, "Log Counter At Maximum" },
	{ 0x5B, 0x03, "Log List Codes Exhausted" },
	{ 0x5C, 0x00, "RPL Status Change" },
	{ 0x5C, 0x01, "Spindles Synchronized" },
	{ 0x5C, 0x02, "Spindles Not Synchronized" },
	{ 0x5D, 0x00, "Failure Prediction Threshold Exceeded" },
	{ 0x5D, 0x01, "Media Failure Prediction Threshold Exceeded" },
	{ 0x5D, 0x02, "Logical Unit Failure Prediction Threshold Exceeded" },
	{ 0x5D, 0x03, "Spare Area Exhaustion Prediction Threshold Exceeded" },
	{ 0x5D, 0x10, "Hardware Impending Failure General Hard Drive Failure" },
	{ 0x5D, 0x11, "Hardware Impending Failure Drive Error Rate Too High" },
	{ 0x5D, 0x12, "Hardware Impending Failure Data Error Rate Too High" },
	{ 0x5D, 0x13, "Hardware Impending Failure Seek Error Rate Too High" },
	{ 0x5D, 0x14, "Hardware Impending Failure Too Many Block Reassigns" },
	{ 0x5D, 0x15, "Hardware Impending Failure Access Times Too High" },
	{ 0x5D, 0x16, "Hardware Impending Failure Start Unit Times Too High" },
	{ 0x5D, 0x17, "Hardware Impending Failure Channel Parametrics" },
	{ 0x5D, 0x18, "Hardware Impending Failure Controller Detected" },
	{ 0x5D, 0x19, "Hardware Impending Failure Throughput Performance" },
	{ 0x5D, 0x1A, "Hardware Impending Failure Seek Time Performance" },
	{ 0x5D, 0x1B, "Hardware Impending Failure Spin-Up Retry Count" },
	{ 0x5D, 0x1C, "Hardware Impending Failure Drive Calibration Retry Count" },
	{ 0x5D, 0x20, "Controller Impending Failure General Hard Drive Failure" },
	{ 0x5D, 0x21, "Controller Impending Failure Drive Error Rate Too High" },
	{ 0x5D, 0x22, "Controller Impending Failure Data Error Rate Too High" },
	{ 0x5D, 0x23, "Controller Impending Failure Seek Error Rate Too High" },
	{ 0x5D, 0x24, "Controller Impending Failure Too Many Block Reassigns" },
	{ 0x5D, 0x25, "Controller Impending Failure Access Times Too High" },
	{ 0x5D, 0x26, "Controller Impending Failure Start Unit Times Too High" },
	{ 0x5D, 0x27, "Controller Impending Failure Channel Parametrics" },
	{ 0x5D, 0x28, "Controller Impending Failure Controller Detected" },
	{ 0x5D, 0x29, "Controller Impending Failure Throughput Performance" },
	{ 0x5D, 0x2A, "Controller Impending Failure Seek Time Performance" },
	{ 0x5D, 0x2B, "Controller Impending Failure Spin-Up Retry Count" },
	{ 0x5D, 0x2C, "Controller Impending Failure Drive Calibration Retry Count" },
	{ 0x5D, 0x30, "Data Channel Impending Failure General Hard Drive Failure" },
	{ 0x5D, 0x31, "Data Channel Impending Failure Drive Error Rate Too High" },
	{ 0x5D, 0x32, "Data Channel Impending Failure Data Error Rate Too High" },
	{ 0x5D, 0x33, "Data Channel Impending Failure Seek Error Rate Too High" },
	{ 0x5D, 0x34, "Data Channel Impending Failure Too Many Block Reassigns" },
	{ 0x5D, 0x35, "Data Channel Impending Failure Access Times Too High" },
	{ 0x5D, 0x36, "Data Channel Impending Failure Start Unit Times Too High" },
	{ 0x5D, 0x37, "Data Channel Impending Failure Channel Parametrics" },
	{ 0x5D, 0x38, "Data Channel Impending Failure Controller Detected" },
	{ 0x5D, 0x39, "Data Channel Impending Failure Throughput Performance" },
	{ 0x5D, 0x3A, "Data Channel Impending Failure Seek Time Performance" },
	{ 0x5D, 0x3B, "Data Channel Impending Failure Spin-Up Retry Count" },
	{ 0x5D, 0x3C, "Data Channel Impending Failure Drive Calibration Retry Count" },
	{ 0x5D, 0x40, "Servo Impending Failure General Hard Drive Failure" },
	{ 0x5D, 0x41, "Servo Impending Failure Drive Error Rate Too High" },
	{ 0x5D, 0x42, "Servo Impending Failure Data Error Rate Too High" },
	{ 0x5D, 0x43, "Servo Impending Failure Seek Error Rate Too High" },
	{ 0x5D, 0x44, "Servo Impending Failure Too Many Block Reassigns" },
	{ 0x5D, 0x45, "Servo Impending Failure Access Times Too High" },
	{ 0x5D, 0x46, "Servo Impending Failure Start Unit Times Too High" },
	{ 0x5D, 0x47, "Servo Impending Failure Channel Parametrics" },
	{ 0x5D, 0x48, "Servo Impending Failure Controller Detected" },
	{ 0x5D, 0x49, "Servo Impending Failure Throughput Performance" },
	{ 0x5D, 0x4A, "Servo Impending Failure Seek Time Performance" },
	{ 0x5D, 0x4B, "Servo Impending Failure Spin-Up Retry Count" },
	{ 0x5D, 0x4C, "Servo Impending Failure Drive Calibration Retry Count" },
	{ 0x5D, 0x50, "Spindle Impending Failure General Hard Drive Failure" },
	{ 0x5D, 0x51, "Spindle Impending Failure Drive Error Rate Too High" },
	{ 0x5D, 0x52, "Spindle Impending Failure Data Error Rate Too High" },
	{ 0x5D, 0x53, "Spindle Impending Failure Seek Error Rate Too High" },
	{ 0x5D, 0x54, "Spindle Impending Failure Too Many Block Reassigns" },
	{ 0x5D, 0x55, "Spindle Impending Failure Access Times Too High" },
	{ 0x5D, 0x56, "Spindle Impending Failure Start Unit Times Too High" },
	{ 0x5D, 0x57, "Spindle Impending Failure Channel Parametrics" },
	{ 0x5D, 0x58, "Spindle Impending Failure Controller Detected" },
	{ 0x5D, 0x59, "Spindle Impending Failure Throughput Performance" },
	{ 0x5D, 0x5A, "Spindle Impending Failure Seek Time Performance" },
	{ 0x5D, 0x5B, "Spindle Impending Failure Spin-Up Retry Count" },
	{ 0x5D, 0x5C, "Spindle Impending Failure Drive Calibration Retry Count" },
	{ 0x5D, 0x60, "Firmware Impending Failure General Hard Drive Failure" },
	{ 0x5D, 0x61, "Firmware Impending Failure Drive Error Rate Too High" },
	{ 0x5D, 0x62, "Firmware Impending Failure Data Error Rate Too High" },
	{ 0x5D, 0x63, "Firmware Impending Failure Seek Error Rate Too High" },
	{ 0x5D, 0x64, "Firmware Impending Failure Too Many Block Reassigns" },
	{ 0x5D, 0x65, "Firmware Impending Failure Access Times Too High" },
	{ 0x5D, 0x66, "Firmware Impending Failure Start Unit Times Too High" },
	{ 0x5D, 0x67, "Firmware Impending Failure Channel Parametrics" },
	{ 0x5D, 0x68, "Firmware Impending Failure Controller Detected" },
	{ 0x5D, 0x69, "Firmware Impending Failure Throughput Performance" },
	{ 0x5D, 0x6A, "Firmware Impending Failure Seek Time Performance" },
	{ 0x5D, 0x6B, "Firmware Impending Failure Spin-Up Retry Count" },
	{ 0x5D, 0x6C, "Firmware Impending Failure Drive Calibration Retry Count" },
	{ 0x5D, 0xFF, "Failure Prediction Threshold Exceeded (false)" },
	{ 0x5E, 0x00, "Low Power Condition On" },
	{ 0x5E, 0x01, "Idle Condition Activated By Timer" },
	{ 0x5E, 0x02, "Standby Condition Activated By Timer" },
	{ 0x5E, 0x03, "Idle Condition Activated By Command" },
	{ 0x5E, 0x04, "Standby Condition Activated By Command" },
	{ 0x5E, 0x41, "Power State Change To Active" },
	{ 0x5E, 0x42, "Power State Change To Idle" },
	{ 0x5E, 0x43, "Power State Change To Standby" },
	{ 0x5E, 0x45, "Power State Change To Sleep" },
	{ 0x5E, 0x47, "Power State Change To Device Control" },
	{ 0x60, 0x00, "Lamp Failure" },
	{ 0x61, 0x00, "Video Acquisition Error" },
	{ 0x61, 0x01, "Unable To Acquire Video" },
	{ 0x61, 0x02, "Out Of Focus" },
	{ 0x62, 0x00, "Scan Head Positioning Error" },
	{ 0x63, 0x00, "End Of User Area Encountered On This Track" },
	{ 0x63, 0x01, "Packet Does Not Fit In Available Space" },
	{ 0x64, 0x00, "Illegal Mode For This Track" },
	{ 0x64, 0x01, "Invalid Packet Size" },
	{ 0x65, 0x00, "Voltage Fault" },
	{ 0x66, 0x00, "Automatic Document Feeder Cover Up" },
	{ 0x66, 0x01, "Automatic Document Feeder Lift Up" },
	{ 0x66, 0x02, "Document Jam In Automatic Document Feeder" },
	{ 0x66, 0x03, "Document Miss Feed Automatic In Document Feeder" },
	{ 0x67, 0x00, "Configuration Failure" },
	{ 0x67, 0x01, "Configuration Of Incapable Logical Units Failed" },
	{ 0x67, 0x02, "Add Logical Unit Failed" },
	{ 0x67, 0x03, "Modification Of Logical Unit Failed" },
	{ 0x67, 0x04, "Exchange Of Logical Unit Failed" },
	{ 0x67, 0x05, "Remove Of Logical Unit Failed" },
	{ 0x67, 0x06, "Attachment Of Logical Unit Failed" },
	{ 0x67, 0x07, "Creation Of Logical Unit Failed" },
	{ 0x67, 0x08, "Assign Failure Occurred" },
	{ 0x67, 0x09, "Multiply Assigned Logical Unit" },
	{ 0x67, 0x0A, "Set Target Port Groups Command Failed" },
	{ 0x68, 0x00, "Logical Unit Not Configured" },
	{ 0x69, 0x00, "Data Loss On Logical Unit" },
	{ 0x69, 0x01, "Multiple Logical Unit Failures" },
	{ 0x69, 0x02, "Parity/Data Mismatch" },
	{ 0x6A, 0x00, "Informational, Refer To Log" },
	{ 0x6B, 0x00, "State Change Has Occurred" },
	{ 0x6B, 0x01, "Redundancy Level Got Better" },
	{ 0x6B, 0x02, "Redundancy Level Got Worse" },
	{ 0x6C, 0x00, "Rebuild Failure Occurred" },
	{ 0x6D, 0x00, "Recalculate Failure Occurred" },
	{ 0x6E, 0x00, "Command To Logical Unit Failed" },
	{ 0x6F, 0x00, "Copy Protection Key Exchange Failure - Authentication Failure" },
	{ 0x6F, 0x01, "Copy Protection Key Exchange Failure - Key Not Present" },
	{ 0x6F, 0x02, "Copy Protection Key Exchange Failure - Key Not Established" },
	{ 0x6F, 0x03, "Read Of Scrambled Sector Without Authentication" },
	{ 0x6F, 0x04, "Media Region Code Is Mismatched To Logical Unit Region" },
	{ 0x6F, 0x05, "Drive Region Must Be Permanent/Region Reset Count Error" },
	/*
	 * ASC 0x70 has an ASCQ range from 0x00 to 0xFF.
	 * 0x70 0xNN DECOMPRESSION EXCEPTION SHORT ALGORITHM ID Of NN
	 */
	{ 0x71, 0x00, "Decompression Exception Long Algorithm ID" },
	{ 0x72, 0x00, "Session Fixation Error" },
	{ 0x72, 0x01, "Session Fixation Error Writing Lead-In" },
	{ 0x72, 0x02, "Session Fixation Error Writing Lead-Out" },
	{ 0x72, 0x03, "Session Fixation Error - Incomplete Track In Session" },
	{ 0x72, 0x04, "Empty Or Partially Written Reserved Track" },
	{ 0x72, 0x05, "No More Track Reservations Allowed" },
	{ 0x73, 0x00, "CD Control Error" },
	{ 0x73, 0x01, "Power Calibration Area Almost Full" },
	{ 0x73, 0x02, "Power Calibration Area Is Full" },
	{ 0x73, 0x03, "Power Calibration Area Error" },
	{ 0x73, 0x04, "Program Memory Area Update Failure" },
	{ 0x73, 0x05, "Program Memory Area Is Full" },
	{ 0x73, 0x06, "RMA/PMA Is Almost Full" },
	{ 0x00, 0x00, NULL }
};

static __inline void
asc2ascii(u_int8_t asc, u_int8_t ascq, char *result, size_t len)
{
	int					i;

	/* Check for a dynamically built description. */
	switch (asc) {
	case 0x40:
		if (ascq >= 0x80) {
			snprintf(result, len,
		            "Diagnostic Failure on Component 0x%02x", ascq);
			return;
		}
		break;
	case 0x4d:
		snprintf(result, len,
	 	    "Tagged Overlapped Commands (0x%02x = TASK TAG)", ascq);
		return;
	case 0x70:
		snprintf(result, len,
		    "Decompression Exception Short Algorithm ID OF 0x%02x",
		    ascq);
		return;
	default:
		break;
	}

	/* Check for a fixed description. */
	for (i = 0; adesc[i].description != NULL; i++) {
		if (adesc[i].asc == asc && adesc[i].ascq == ascq) {
			strlcpy(result, adesc[i].description, len);
			return;
		}
	}

	/* Just print out the ASC and ASCQ values as a description. */
	snprintf(result, len, "ASC 0x%02x ASCQ 0x%02x", asc, ascq);
}
#endif /* SCSITERSE */

void
scsi_print_sense(struct scsi_xfer *xs)
{
	struct scsi_sense_data			*sense = &xs->sense;
	u_int8_t				serr = sense->error_code &
						    SSD_ERRCODE;
	int32_t					info;
	char					*sbs;

	sc_print_addr(xs->sc_link);

	/* XXX For error 0x71, current opcode is not the relevant one. */
	printf("%sCheck Condition (error %#x) on opcode 0x%x\n",
	    (serr == SSD_ERRCODE_DEFERRED) ? "DEFERRED " : "", serr,
	    xs->cmd->opcode);

	if (serr != SSD_ERRCODE_CURRENT && serr != SSD_ERRCODE_DEFERRED) {
		if ((sense->error_code & SSD_ERRCODE_VALID) != 0) {
			struct scsi_sense_data_unextended *usense =
			    (struct scsi_sense_data_unextended *)sense;
			printf("   AT BLOCK #: %d (decimal)",
			    _3btol(usense->block));
		}
		return;
	}

	printf("    SENSE KEY: %s\n", scsi_decode_sense(sense,
	    DECODE_SENSE_KEY));

	if (sense->flags & (SSD_FILEMARK | SSD_EOM | SSD_ILI)) {
		char pad = ' ';

		printf("             ");
		if (sense->flags & SSD_FILEMARK) {
			printf("%c Filemark Detected", pad);
			pad = ',';
		}
		if (sense->flags & SSD_EOM) {
			printf("%c EOM Detected", pad);
			pad = ',';
		}
		if (sense->flags & SSD_ILI)
			printf("%c Incorrect Length Indicator Set", pad);
		printf("\n");
	}

	/*
	 * It is inconvenient to use device type to figure out how to
	 * format the info fields. So print them as 32 bit integers.
	 */
	info = _4btol(&sense->info[0]);
	if (info)
		printf("         INFO: 0x%x (VALID flag %s)\n", info,
		    sense->error_code & SSD_ERRCODE_VALID ? "on" : "off");

	if (sense->extra_len < 4)
		return;

	info = _4btol(&sense->cmd_spec_info[0]);
	if (info)
		printf(" COMMAND INFO: 0x%x\n", info);
	sbs = scsi_decode_sense(sense, DECODE_ASC_ASCQ);
	if (strlen(sbs) > 0)
		printf("     ASC/ASCQ: %s\n", sbs);
	if (sense->fru != 0)
		printf("     FRU CODE: 0x%x\n", sense->fru);
	sbs = scsi_decode_sense(sense, DECODE_SKSV);
	if (strlen(sbs) > 0)
		printf("         SKSV: %s\n", sbs);
}

char *
scsi_decode_sense(struct scsi_sense_data *sense, int flag)
{
	static char				rqsbuf[132];
	u_int16_t				count;
	u_int8_t				skey, spec_1;
	int					len;

	bzero(rqsbuf, sizeof(rqsbuf));

	skey = sense->flags & SSD_KEY;
	spec_1 = sense->sense_key_spec_1;
	count = _2btol(&sense->sense_key_spec_2);

	switch (flag) {
	case DECODE_SENSE_KEY:
		strlcpy(rqsbuf, sense_keys[skey], sizeof(rqsbuf));
		break;
	case DECODE_ASC_ASCQ:
		asc2ascii(sense->add_sense_code, sense->add_sense_code_qual,
		    rqsbuf, sizeof(rqsbuf));
		break;
	case DECODE_SKSV:
		if (sense->extra_len < 9 || ((spec_1 & SSD_SCS_VALID) == 0))
			break;
		switch (skey) {
		case SKEY_ILLEGAL_REQUEST:
			len = snprintf(rqsbuf, sizeof rqsbuf,
			    "Error in %s, Offset %d",
			    (spec_1 & SSD_SCS_CDB_ERROR) ? "CDB" : "Parameters",
			    count);
			if ((len != -1 && len < sizeof rqsbuf) &&
			    (spec_1 & SSD_SCS_VALID_BIT_INDEX))
				snprintf(rqsbuf+len, sizeof rqsbuf - len,
				    ", bit %d", spec_1 & SSD_SCS_BIT_INDEX);
			break;
		case SKEY_RECOVERED_ERROR:
		case SKEY_MEDIUM_ERROR:
		case SKEY_HARDWARE_ERROR:
			snprintf(rqsbuf, sizeof rqsbuf,
			    "Actual Retry Count: %d", count);
			break;
		case SKEY_NOT_READY:
			snprintf(rqsbuf, sizeof rqsbuf,
			    "Progress Indicator: %d", count);
			break;
		default:
			break;
		}
		break;
	default:
		break;
	}

	return (rqsbuf);
}

#ifdef SCSIDEBUG
/*
 * Given a scsi_xfer, dump the request, in all its glory
 */
void
scsi_xs_show(struct scsi_xfer *xs)
{
	u_char *b = (u_char *)xs->cmd;
	int i = 0;

	sc_print_addr(xs->sc_link);
	printf("xs  (%p): ", xs);

	printf("flg(0x%x)", xs->flags);
	printf("sc_link(%p)", xs->sc_link);
	printf("retr(0x%x)", xs->retries);
	printf("timo(0x%x)", xs->timeout);
	printf("data(%p)", xs->data);
	printf("res(0x%x)", xs->resid);
	printf("err(0x%x)", xs->error);
	printf("bp(%p)\n", xs->bp);

	sc_print_addr(xs->sc_link);
	printf("cmd (%p): ", xs->cmd);

	if ((xs->flags & SCSI_RESET) == 0) {
		while (i < xs->cmdlen) {
			if (i)
				printf(",");
			printf("%x", b[i++]);
		}
		printf("-[%d bytes]\n", xs->datalen);
	} else
		printf("-RESET-\n");
}

void
scsi_show_mem(u_char *address, int num)
{
	int x;

	printf("------------------------------");
	for (x = 0; x < num; x++) {
		if ((x % 16) == 0)
			printf("\n%03d: ", x);
		printf("%02x ", *address++);
	}
	printf("\n------------------------------\n");
}
#endif /* SCSIDEBUG */

void
scsi_cmd_rw_decode(struct scsi_generic *cmd, u_int64_t *blkno,
    u_int32_t *nblks)
{
	switch (cmd->opcode) {
	case READ_COMMAND:
	case WRITE_COMMAND: {
		struct scsi_rw *rw = (struct scsi_rw *)cmd;
		*blkno = _3btol(rw->addr) & (SRW_TOPADDR << 16 | 0xffff);
		*nblks = rw->length ? rw->length : 0x100;
		break;
	}
	case READ_BIG:
	case WRITE_BIG: {
		struct scsi_rw_big *rwb = (struct scsi_rw_big *)cmd;
		*blkno = _4btol(rwb->addr);
		*nblks = _2btol(rwb->length);
		break;
	}
	case READ_12:
	case WRITE_12: {
		struct scsi_rw_12 *rw12 = (struct scsi_rw_12 *)cmd;
		*blkno = _4btol(rw12->addr);
		*nblks = _4btol(rw12->length);
		break;
	}
	case READ_16:
	case WRITE_16: {
		struct scsi_rw_16 *rw16 = (struct scsi_rw_16 *)cmd;
		*blkno = _8btol(rw16->addr);
		*nblks = _4btol(rw16->length);
		break;
	}
	default:
		panic("scsi_cmd_rw_decode: bad opcode 0x%02x", cmd->opcode);
	}
}