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path: root/sys/scsi/scsi_base.c
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/*	$OpenBSD: scsi_base.c,v 1.31 2001/08/25 19:29:16 fgsch 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 struct scsi_xfer *scsi_make_xs __P((struct scsi_link *,
    struct scsi_generic *, int cmdlen, u_char *data_addr,
    int datalen, int retries, int timeout, struct buf *, int flags));
static __inline void asc2ascii __P((u_char asc, u_char ascq, char *result));
int	sc_err1 __P((struct scsi_xfer *, int));
int	scsi_interpret_sense __P((struct scsi_xfer *));
char   *scsi_decode_sense __P((void *, int));

struct pool scsi_xfer_pool;

/*
 * 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;

	/* Initialize the scsi_xfer pool. */
	pool_init(&scsi_xfer_pool, sizeof(struct scsi_xfer), 0,
	    0, 0, "scxspl", 0, NULL, NULL, M_DEVBUF);
}

/*
 * Get a scsi transfer structure for the caller. Charge the structure
 * to the device that is referenced by the sc_link structure. If the 
 * sc_link structure has no 'credits' then the device already has the
 * maximum number or outstanding operations under way. In this stage,
 * wait on the structure so that when one is freed, we are awoken again
 * If the SCSI_NOSLEEP flag is set, then do not wait, but rather, return
 * a NULL pointer, signifying that no slots were available
 * Note in the link structure, that we are waiting on it.
 */

struct scsi_xfer *
scsi_get_xs(sc_link, flags)
	struct scsi_link *sc_link;	/* who to charge the xs to */
	int flags;			/* if this call can sleep */
{
	struct scsi_xfer *xs;
	int s;

	SC_DEBUG(sc_link, SDEV_DB3, ("scsi_get_xs\n"));

	s = splbio();
	while (sc_link->openings <= 0) {
		SC_DEBUG(sc_link, SDEV_DB3, ("sleeping\n"));
		if ((flags & SCSI_NOSLEEP) != 0) {
			splx(s);
			return (NULL);
		}
		sc_link->flags |= SDEV_WAITING;
		(void) tsleep(sc_link, PRIBIO, "getxs", 0);
	}
	SC_DEBUG(sc_link, SDEV_DB3, ("calling pool_get\n"));
	xs = pool_get(&scsi_xfer_pool,
	    ((flags & SCSI_NOSLEEP) != 0 ? M_NOWAIT : M_WAITOK));
	if (xs != NULL) {
		sc_link->openings--;
		xs->flags = flags;
	} else {
		sc_print_addr(sc_link);
		printf("cannot allocate scsi xs\n");
	}
	splx(s);

	SC_DEBUG(sc_link, SDEV_DB3, ("returning\n"));

	return (xs);
}

/*
 * Given a scsi_xfer struct, and a device (referenced through sc_link)
 * return the struct to the free pool and credit the device with it
 * If another process is waiting for an xs, do a wakeup, let it proceed
 */
void 
scsi_free_xs(xs, flags)
	struct scsi_xfer *xs;
	int flags;
{
	struct scsi_link *sc_link = xs->sc_link;

	SC_DEBUG(sc_link, SDEV_DB3, ("scsi_free_xs\n"));

	pool_put(&scsi_xfer_pool, xs);

	/* if was 0 and someone waits, wake them up */
	sc_link->openings++;
	if ((sc_link->flags & SDEV_WAITING) != 0) {
		sc_link->flags &= ~SDEV_WAITING;
		wakeup(sc_link);
	} else {
		if (sc_link->device->start) {
			SC_DEBUG(sc_link, SDEV_DB2,
			    ("calling private start()\n"));
			(*(sc_link->device->start)) (sc_link->device_softc);
		}
	}
}

/*
 * Make a scsi_xfer, and return a pointer to it.
 */
static __inline struct scsi_xfer *
scsi_make_xs(sc_link, scsi_cmd, cmdlen, data_addr, datalen,
    retries, timeout, bp, flags)
	struct scsi_link *sc_link;
	struct scsi_generic *scsi_cmd;
	int cmdlen;
	u_char *data_addr;
	int datalen;
	int retries;
	int timeout;
	struct buf *bp;
	int flags;
{
	struct scsi_xfer *xs;

	if ((xs = scsi_get_xs(sc_link, flags)) == NULL)
		return NULL;

	/*
	 * Fill out the scsi_xfer structure.  We don't know whose context
	 * the cmd is in, so copy it.
	 */
	xs->sc_link = sc_link;
	bcopy(scsi_cmd, &xs->cmdstore, cmdlen);
	xs->cmd = &xs->cmdstore;
	xs->cmdlen = cmdlen;
	xs->data = data_addr;
	xs->datalen = datalen;
	xs->retries = retries;
	xs->timeout = timeout;
	xs->bp = bp;
	xs->req_sense_length = 0;	/* XXX - not used by scsi internals */

	/*
	 * Set the LUN in the CDB.  This may only be needed if we have an
	 * older device.  However, we also set it for more modern SCSI
	 * devices "just in case".  The old code assumed everything newer
	 * than SCSI-2 would not need it, but why risk it?  This was the
	 * old conditional:
	 *
	 * if ((sc_link->scsi_version & SID_ANSII) <= 2)
	 */
	xs->cmd->bytes[0] &= ~SCSI_CMD_LUN_MASK;
	xs->cmd->bytes[0] |=
	    ((sc_link->lun << SCSI_CMD_LUN_SHIFT) & SCSI_CMD_LUN_MASK);

	return xs;
}

/*
 * Find out from the device what its capacity is.
 */
u_long
scsi_size(sc_link, flags)
	struct scsi_link *sc_link;
	int flags;
{
	struct scsi_read_cap_data rdcap;
	struct scsi_read_capacity scsi_cmd;

	/*
	 * make up a scsi command and ask the scsi driver to do
	 * it for you.
	 */
	bzero(&scsi_cmd, sizeof(scsi_cmd));
	scsi_cmd.opcode = READ_CAPACITY;

	/*
	 * If the command works, interpret the result as a 4 byte
	 * number of blocks
	 */
	if (scsi_scsi_cmd(sc_link, (struct scsi_generic *)&scsi_cmd,
			  sizeof(scsi_cmd), (u_char *)&rdcap, sizeof(rdcap),
			  2, 20000, NULL, flags | SCSI_DATA_IN) != 0) {
		sc_print_addr(sc_link);
		printf("could not get size\n");
		return 0;
	}

	return _4btol(rdcap.addr) + 1;
}

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

	bzero(&scsi_cmd, sizeof(scsi_cmd));
	scsi_cmd.opcode = TEST_UNIT_READY;

	return scsi_scsi_cmd(sc_link, (struct scsi_generic *) &scsi_cmd,
	    sizeof(scsi_cmd), 0, 0, 5, 10000, NULL, flags);
}

/*
 * Do a scsi operation, asking a device to run as SCSI-II if it can.
 */
int 
scsi_change_def(sc_link, flags)
	struct scsi_link *sc_link;
	int flags;
{
	struct scsi_changedef scsi_cmd;

	bzero(&scsi_cmd, sizeof(scsi_cmd));
	scsi_cmd.opcode = CHANGE_DEFINITION;
	scsi_cmd.how = SC_SCSI_2;

	return scsi_scsi_cmd(sc_link, (struct scsi_generic *) &scsi_cmd,
	    sizeof(scsi_cmd), 0, 0, 2, 100000, NULL, flags);
}

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

	bzero(&scsi_cmd, sizeof(scsi_cmd));
	scsi_cmd.opcode = INQUIRY;
	scsi_cmd.length = sizeof(struct scsi_inquiry_data);

	return scsi_scsi_cmd(sc_link, (struct scsi_generic *) &scsi_cmd,
	    sizeof(scsi_cmd), (u_char *) inqbuf,
	    sizeof(struct scsi_inquiry_data), 2, 10000, NULL,
	    SCSI_DATA_IN | flags);
}

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

	bzero(&scsi_cmd, sizeof(scsi_cmd));
	scsi_cmd.opcode = PREVENT_ALLOW;
	scsi_cmd.how = type;
	return scsi_scsi_cmd(sc_link, (struct scsi_generic *) &scsi_cmd,
	    sizeof(scsi_cmd), 0, 0, 2, 5000, NULL, flags);
}

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

	if ((sc_link->quirks & SDEV_NOSTARTUNIT) == SDEV_NOSTARTUNIT)
		return 0;

	bzero(&scsi_cmd, sizeof(scsi_cmd));
	scsi_cmd.opcode = START_STOP;
	scsi_cmd.byte2 = 0x00;
	scsi_cmd.how = type;
	return scsi_scsi_cmd(sc_link, (struct scsi_generic *) &scsi_cmd,
	    sizeof(scsi_cmd), 0, 0, 2,
	    type == SSS_START ? 30000 : 10000, NULL, flags);
}

/*
 * This routine is called by the scsi interrupt when the transfer is complete.
 */
void 
scsi_done(xs)
	struct scsi_xfer *xs;
{
	struct scsi_link *sc_link = xs->sc_link;
	struct buf *bp;
	int error;

	SC_DEBUG(sc_link, SDEV_DB2, ("scsi_done\n"));
#ifdef	SCSIDEBUG
	if ((sc_link->flags & SDEV_DB1) != 0)
		show_scsi_cmd(xs);
#endif /* SCSIDEBUG */

	/*
 	 * If it's a user level request, bypass all usual completion processing,
 	 * let the user work it out.. We take reponsibility for freeing the
 	 * xs when the user returns. (and restarting the device's queue).
 	 */
	if ((xs->flags & SCSI_USER) != 0) {
		SC_DEBUG(sc_link, SDEV_DB3, ("calling user done()\n"));
		scsi_user_done(xs); /* to take a copy of the sense etc. */
		SC_DEBUG(sc_link, SDEV_DB3, ("returned from user done()\n "));

		scsi_free_xs(xs, SCSI_NOSLEEP); /* restarts queue too */
		SC_DEBUG(sc_link, SDEV_DB3, ("returning to adapter\n"));
		return;
	}

	if (!((xs->flags & (SCSI_NOSLEEP | SCSI_POLL)) == SCSI_NOSLEEP)) {
		/*
		 * if it's a normal upper level request, then ask
		 * the upper level code to handle error checking
		 * rather than doing it here at interrupt time
		 */
		wakeup(xs);
		return;
	}

	/*
	 * Go and handle errors now.
	 * If it returns ERESTART then we should RETRY
	 */
retry:
	error = sc_err1(xs, 1);
	if (error == ERESTART) {
		switch ((*(sc_link->adapter->scsi_cmd)) (xs)) {
		case SUCCESSFULLY_QUEUED:
			return;

		case TRY_AGAIN_LATER:
			xs->error = XS_BUSY;
		case COMPLETE:
			goto retry;
		}
	}

	bp = xs->bp;
	if (bp) {
		if (error) {
			bp->b_error = error;
			bp->b_flags |= B_ERROR;
			bp->b_resid = bp->b_bcount;
		} else {
			bp->b_error = 0;
			bp->b_resid = xs->resid;
		}
	}
	if (sc_link->device->done) {
		/*
		 * Tell the device the operation is actually complete.
		 * No more will happen with this xfer.  This for
		 * notification of the upper-level driver only; they
		 * won't be returning any meaningful information to us.
		 */
		(*sc_link->device->done)(xs);
	}
	scsi_free_xs(xs, SCSI_NOSLEEP);
	if (bp)
		biodone(bp);
}

int
scsi_execute_xs(xs)
	struct scsi_xfer *xs;
{
	int error;
	int s;

	xs->flags &= ~ITSDONE;
	xs->error = XS_NOERROR;
	xs->resid = xs->datalen;
	xs->status = 0;

retry:
	/*
	 * Do the transfer. If we are polling we will return:
	 * COMPLETE,  Was poll, and scsi_done has been called
	 * TRY_AGAIN_LATER, Adapter short resources, try again
	 * 
	 * if under full steam (interrupts) it will return:
	 * SUCCESSFULLY_QUEUED, will do a wakeup when complete
	 * TRY_AGAIN_LATER, (as for polling)
	 * After the wakeup, we must still check if it succeeded
	 * 
	 * If we have a SCSI_NOSLEEP (typically because we have a buf)
	 * we just return.  All the error proccessing and the buffer
	 * code both expect us to return straight to them, so as soon
	 * as the command is queued, return.
	 */
	switch ((*(xs->sc_link->adapter->scsi_cmd)) (xs)) {
	case SUCCESSFULLY_QUEUED:
		if ((xs->flags & (SCSI_NOSLEEP | SCSI_POLL)) == SCSI_NOSLEEP)
			return EJUSTRETURN;
#ifdef DIAGNOSTIC
		if (xs->flags & SCSI_NOSLEEP)
			panic("scsi_execute_xs: NOSLEEP and POLL");
#endif
		s = splbio();
		while ((xs->flags & ITSDONE) == 0)
			tsleep(xs, PRIBIO + 1, "scsi_scsi_cmd", 0);
		splx(s);
	case COMPLETE:		/* Polling command completed ok */
		if (xs->bp)
			return EJUSTRETURN;
	doit:
		SC_DEBUG(xs->sc_link, SDEV_DB3, ("back in cmd()\n"));
		if ((error = sc_err1(xs, 0)) != ERESTART)
			return error;
		goto retry;

	case TRY_AGAIN_LATER:	/* adapter resource shortage */
		xs->error = XS_BUSY;
		goto doit;

	default:
		panic("scsi_execute_xs: invalid return code");
	}

#ifdef DIAGNOSTIC
	panic("scsi_execute_xs: impossible");
#endif
	return EINVAL;
}

/*
 * ask the scsi driver to perform a command for us.
 * tell it where to read/write the data, and how
 * long the data is supposed to be. If we have  a buf
 * to associate with the transfer, we need that too.
 */
int 
scsi_scsi_cmd(sc_link, scsi_cmd, cmdlen, data_addr, datalen,
    retries, timeout, bp, flags)
	struct scsi_link *sc_link;
	struct scsi_generic *scsi_cmd;
	int cmdlen;
	u_char *data_addr;
	int datalen;
	int retries;
	int timeout;
	struct buf *bp;
	int flags;
{
	struct scsi_xfer *xs;
	int error;

	SC_DEBUG(sc_link, SDEV_DB2, ("scsi_cmd\n"));

#ifdef DIAGNOSTIC
	if (bp != 0 && (flags & SCSI_NOSLEEP) == 0)
		panic("scsi_scsi_cmd: buffer without nosleep");
#endif

	if ((xs = scsi_make_xs(sc_link, scsi_cmd, cmdlen, data_addr, datalen,
	    retries, timeout, bp, flags)) == NULL)
		return ENOMEM;

	if ((error = scsi_execute_xs(xs)) == EJUSTRETURN)
		return 0;

	/*
	 * we have finished with the xfer stuct, free it and
	 * check if anyone else needs to be started up.
	 */
	scsi_free_xs(xs, flags);
	return error;
}

int 
sc_err1(xs, async)
	struct scsi_xfer *xs;
	int async;
{
	int error;

	SC_DEBUG(xs->sc_link, SDEV_DB3, ("sc_err1,err = 0x%x \n", xs->error));

	/*
	 * If it has a buf, we might be working with
	 * a request from the buffer cache or some other
	 * piece of code that requires us to process
	 * errors at interrupt time. We have probably
	 * been called by scsi_done()
	 */
	switch (xs->error) {
	case XS_NOERROR:	/* nearly always hit this one */
		error = 0;
		break;

	case XS_SENSE:
	case XS_SHORTSENSE:
		if ((error = scsi_interpret_sense(xs)) == ERESTART) {
			if (xs->error == XS_BUSY) {
				xs->error = XS_SENSE;
				goto sense_retry;
			}
			goto retry;
		}
		SC_DEBUG(xs->sc_link, SDEV_DB3,
		    ("scsi_interpret_sense returned %d\n", error));
		break;

	case XS_BUSY:
	sense_retry:
		if (xs->retries) {
			if ((xs->flags & SCSI_POLL) != 0)
				delay(1000000);
			else if ((xs->flags & SCSI_NOSLEEP) == 0) {
				tsleep(&lbolt, PRIBIO, "scbusy", 0);
			} else
				goto lose;
		}
	case XS_TIMEOUT:
	retry:
		if (xs->retries--) {
			xs->error = XS_NOERROR;
			xs->flags &= ~ITSDONE;
			return ERESTART;
		}
	case XS_DRIVER_STUFFUP:
	lose:
		error = EIO;
		break;

	case XS_SELTIMEOUT:
		/* XXX Disable device? */
		error = EIO;
		break;

	case XS_RESET:
		if (xs->retries) {
			SC_DEBUG(xs->sc_link, SDEV_DB3,
			    ("restarting command destroyed by reset\n"));
			goto retry;
		}
		error = EIO;
		break;

	default:
		sc_print_addr(xs->sc_link);
		printf("unknown error category from scsi driver\n");
		error = EIO;
		break;
	}

	return error;
}

/*
 * 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(xs)
	struct scsi_xfer *xs;
{
	struct scsi_sense_data *sense;
	struct scsi_link *sc_link = xs->sc_link;
	u_int8_t key;
	u_int32_t info;
	int error;

	sense = &xs->sense;
#ifdef	SCSIDEBUG
	if ((sc_link->flags & SDEV_DB1) != 0) {
		int count;
		printf("code%x valid%x ",
		    sense->error_code & SSD_ERRCODE,
		    sense->error_code & SSD_ERRCODE_VALID ? 1 : 0);
		printf("seg%x key%x ili%x eom%x fmark%x\n",
		    sense->segment,
		    sense->flags & SSD_KEY,
		    sense->flags & SSD_ILI ? 1 : 0,
		    sense->flags & SSD_EOM ? 1 : 0,
		    sense->flags & SSD_FILEMARK ? 1 : 0);
		printf("info: %x %x %x %x followed by %d extra bytes\n",
		    sense->info[0],
		    sense->info[1],
		    sense->info[2],
		    sense->info[3],
		    sense->extra_len);
		printf("extra: ");
		for (count = 0; count < sense->extra_len; count++)
			printf("%x ", sense->cmd_spec_info[count]);
		printf("\n");
	}
#endif	/* SCSIDEBUG */
	/*
	 * If the device has it's own error handler, call it first.
	 * If it returns a legit error value, return that, otherwise
	 * it wants us to continue with normal error processing.
	 */
	if (sc_link->device->err_handler) {
		SC_DEBUG(sc_link, SDEV_DB2, ("calling private err_handler()\n"));
		error = (*sc_link->device->err_handler) (xs);
		if (error != SCSIRET_CONTINUE)
			return error;		/* error >= 0  better ? */
	}
	/* otherwise use the default */
	switch (sense->error_code & SSD_ERRCODE) {
		/*
		 * If it's code 70, use the extended stuff and interpret the key
		 */
	case 0x71:		/* delayed error */
		sc_print_addr(sc_link);
		key = sense->flags & SSD_KEY;
		printf(" DEFERRED ERROR, key = 0x%x\n", key);
		/* FALLTHROUGH */
	case 0x70:
		if ((sense->error_code & SSD_ERRCODE_VALID) != 0)
			info = _4btol(sense->info);
		else
			info = 0;
		key = sense->flags & SSD_KEY;

		switch (key) {
		case SKEY_NO_SENSE:
		case SKEY_RECOVERED_ERROR:
			if (xs->resid == xs->datalen)
				xs->resid = 0;	/* not short read */
		case SKEY_EQUAL:
			error = 0;
			break;
		case SKEY_NOT_READY:
			if ((sc_link->flags & SDEV_REMOVABLE) != 0)
				sc_link->flags &= ~SDEV_MEDIA_LOADED;
			if ((xs->flags & SCSI_IGNORE_NOT_READY) != 0)
				return 0;
			if (xs->retries && sense->add_sense_code == 0x04 &&
			    sense->add_sense_code_qual == 0x01) {
				xs->error = XS_BUSY;	/* ie. sense_retry */
				return ERESTART;
			}
			if (xs->retries && !(sc_link->flags & SDEV_REMOVABLE)) {
				delay(1000000);
				return ERESTART;
			}
			if ((xs->flags & SCSI_SILENT) != 0)
				return EIO;
			error = EIO;
			break;
		case SKEY_ILLEGAL_REQUEST:
			if ((xs->flags & SCSI_IGNORE_ILLEGAL_REQUEST) != 0)
				return 0;
			if ((xs->flags & SCSI_SILENT) != 0)
				return EIO;
			error = EINVAL;
			break;
		case SKEY_UNIT_ATTENTION:
			if (sense->add_sense_code == 0x29 &&
			    sense->add_sense_code_qual == 0x00)
				return (ERESTART); /* device or bus reset */
			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 ERESTART;
			if ((xs->flags & SCSI_SILENT) != 0)
				return EIO;
			error = EIO;
			break;
		case SKEY_WRITE_PROTECT:
			error = EROFS;
			break;
		case SKEY_BLANK_CHECK:
			error = 0;
			break;
		case SKEY_ABORTED_COMMAND:
			error = ERESTART;
			break;
		case SKEY_VOLUME_OVERFLOW:
			error = ENOSPC;
			break;
		default:
			error = EIO;
			break;
		}

		if ((xs->flags & SCSI_SILENT) == 0)
			scsi_print_sense(xs, 0);

		return error;

	/*
	 * Not code 70, just report it
	 */
	default:
		sc_print_addr(sc_link);
		printf("Sense Error Code %d",
		    sense->error_code & SSD_ERRCODE);
		if ((sense->error_code & SSD_ERRCODE_VALID) != 0) {
			struct scsi_sense_data_unextended *usense =
			    (struct scsi_sense_data_unextended *)sense;
			printf(" at block no. %d (decimal)",
			    _3btol(usense->block));
		}
		printf("\n");
		return EIO;
	}
}

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


/*
 * Print out the scsi_link structure's address info.
 */
void
sc_print_addr(sc_link)
	struct scsi_link *sc_link;
{

	printf("%s(%s:%d:%d): ",
	    sc_link->device_softc ?
	    ((struct device *)sc_link->device_softc)->dv_xname : "probe",
	    ((struct device *)sc_link->adapter_softc)->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"
};
#ifndef SCSITERSE
static const struct {
	u_char 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" },
	{ 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" },
	{ 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" },
	{ 0x09, 0x00, "Track Following Error" },
	{ 0x09, 0x01, "Tracking Servo Failure" },
	{ 0x09, 0x02, "Focus Servo Failure" },
	{ 0x09, 0x03, "Spindle Servo Failure" },
	{ 0x0A, 0x00, "Error Log Overflow" },
	{ 0x0C, 0x00, "Write Error" },
	{ 0x0C, 0x01, "Write Error Recovered with Auto Reallocation" },
	{ 0x0C, 0x02, "Write Error - Auto Reallocate Failed" },
	{ 0x10, 0x00, "ID CRC Or ECC Error" },
	{ 0x11, 0x00, "Unrecovered Read Error" },
	{ 0x11, 0x01, "Read Retried 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 Found" },
	{ 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" },
	{ 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" },
	{ 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" },
	{ 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" },
	{ 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 LEC" },
	{ 0x18, 0x05, "Recovered Data - Recommend Reassignment" },
	{ 0x18, 0x06, "Recovered Data - Recommend Rewrite" },
	{ 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" },
	{ 0x20, 0x00, "Invalid Command Operation Code" },
	{ 0x21, 0x00, "Logical Block Address Out of Range" },
	{ 0x21, 0x01, "Invalid Element Address" },
	{ 0x22, 0x00, "Illegal Function (Should 20 00, 24 00, or 26 00)" },
	{ 0x24, 0x00, "Illegal Field in CDB" },
	{ 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" },
	{ 0x27, 0x00, "Write Protected" },
	{ 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" },
	{ 0x2A, 0x00, "Parameters Changed" },
	{ 0x2A, 0x01, "Mode Parameters Changed" },
	{ 0x2A, 0x02, "Log Parameters Changed" },
	{ 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" },
	{ 0x2D, 0x00, "Overwrite Error On Update In Place" },
	{ 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" },
	{ 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" },
	{ 0x36, 0x00, "Ribbon, Ink, or Toner Failure" },
	{ 0x37, 0x00, "Rounded Parameter" },
	{ 0x39, 0x00, "Saving Parameters Not Supported" },
	{ 0x3A, 0x00, "Medium Not Present" },
	{ 0x3B, 0x00, "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 Begining 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" },
	{ 0x3D, 0x00, "Invalid Bits In IDENTFY Message" },
	{ 0x3E, 0x00, "Logical Unit Has Not Self-Configured Yet" },
	{ 0x3F, 0x00, "Target Operating Conditions Have Changed" },
	{ 0x3F, 0x01, "Microcode Has Changed" },
	{ 0x3F, 0x02, "Changed Operating Definition" },
	{ 0x3F, 0x03, "INQUIRY Data Has Changed" },
	{ 0x40, 0x00, "RAM FAILURE (Should Use 40 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" },
	{ 0x48, 0x00, "INITIATOR DETECTED ERROR Message Received" },
	{ 0x49, 0x00, "Invalid Message Error" },
	{ 0x4A, 0x00, "Command Phase Error" },
	{ 0x4B, 0x00, "Data Phase Error" },
	{ 0x4C, 0x00, "Logical Unit Failed Self-Configuration" },
	{ 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" },
	{ 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" },
	{ 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 (Unspecified)" },
	{ 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" },
	{ 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" },
	{ 0x64, 0x00, "Illegal Mode For This Track" },
	{ 0x00, 0x00, NULL }
};

static __inline void
asc2ascii(asc, ascq, result)
	u_char asc, ascq;
	char *result;
{
	register int i = 0;

	while (adesc[i].description != NULL) {
		if (adesc[i].asc == asc && adesc[i].ascq == ascq)
			break;
		i++;
	}
	if (adesc[i].description == NULL) {
		if (asc == 0x40 && ascq != 0) {
			(void) sprintf(result,
			    "Diagnostic Failure on Component 0x%02x",
			    ascq & 0xff);
		} else {
			(void) sprintf(result, "ASC 0x%02x ASCQ 0x%02x",
			    asc & 0xff, ascq & 0xff);
		}
	} else {
		(void) strcpy(result, adesc[i].description);
	}
}

#else

static __inline void
asc2ascii(asc, ascq, result)
	u_char asc, ascq;
	char *result;
{
	(void) sprintf(result, "ASC 0x%02x ASCQ 0x%02x", asc & 0xff,
	    ascq & 0xff);
}
#endif /* SCSITERSE */

void
scsi_print_sense(xs, verbosity)
	struct scsi_xfer *xs;
	int verbosity;
{
	int32_t info;
	register int i, j, k;
	char *sbs, *s;

	sc_print_addr(xs->sc_link);
	s = (char *) &xs->sense;
	printf("Check Condition on opcode 0x%x\n", xs->cmd->opcode);

	/*
	 * Basics- print out SENSE KEY
	 */
	printf("    SENSE KEY: %s\n", scsi_decode_sense(s, 0));

	/*
 	 * Print out, unqualified but aligned, FMK, EOM and ILI status.
	 */
	if (s[2] & 0xe0) {
		char pad = ' ';

		printf("             ");
		if (s[2] & SSD_FILEMARK) {
			printf("%c Filemark Detected", pad);
			pad = ',';
		}
		if (s[2] & SSD_EOM) {
			printf("%c EOM Detected", pad);
			pad = ',';
		}
		if (s[2] & SSD_ILI)
			printf("%c Incorrect Length Indicator Set", pad);
		printf("\n");
	}
	/*
	 * Now we should figure out, based upon device type, how
	 * to format the information field. Unfortunately, that's
	 * not convenient here, so we'll print it as a signed
	 * 32 bit integer.
	 */
	info = _4btol(&s[3]);
	if (info)
		printf("   INFO FIELD: %u\n", info);

	/*
	 * Now we check additional length to see whether there is
	 * more information to extract.
	 */

	/* enough for command specific information? */
	if (s[7] < 4)
		return;
	info = _4btol(&s[8]);
	if (info)
		printf(" COMMAND INFO: %d (0x%x)\n", info, info);

	/*
	 * Decode ASC && ASCQ info, plus FRU, plus the rest...
	 */

	sbs = scsi_decode_sense(s, 1);
	if (sbs)
		printf("     ASC/ASCQ: %s\n", sbs);
	if (s[14] != 0)
		printf("     FRU CODE: 0x%x\n", s[14] & 0xff);
	sbs = scsi_decode_sense(s, 3);
	if (sbs)
		printf("         SKSV: %s\n", sbs);
	if (verbosity == 0)
		return;

	/*
	 * Now figure whether we should print any additional informtion.
	 *
	 * Where should we start from? If we had SKSV data,
	 * start from offset 18, else from offset 15.
	 *
	 * From that point until the end of the buffer, check for any
	 * nonzero data. If we have some, go back and print the lot,
	 * otherwise we're done.
	 */
	if (sbs)
		i = 18;
	else
		i = 15;

	for (j = i; j < sizeof (xs->sense); j++)
		if (s[j])
			break;
	if (j == sizeof (xs->sense))
		return;

	printf(" Additional Sense Information (byte %d out...):\n", i);
	if (i == 15) {
		printf("        %2d:", i);
		k = 7;
	} else {
		printf("        %2d:", i);
		k = 2;
		j -= 2;
	}
	while (j > 0) {
		if (i >= sizeof (xs->sense))
			break;
		if (k == 8) {
			k = 0;
			printf("\n        %2d:", i);
		}
		printf(" 0x%02x", s[i] & 0xff);
		k++;
		j--;
		i++;
	}
	printf("\n");
}

char *
scsi_decode_sense(sinfo, flag)
	void *sinfo;
	int flag;
{
	u_char *snsbuf, skey;
	static char rqsbuf[132];

	skey = 0;

	snsbuf = (u_char *) sinfo;
	if (flag == 0 || flag == 2 || flag == 3) {
		skey = snsbuf[2] & 0xf;
	}
	if (flag == 0) {		/* Sense Key Only */
		(void) strcpy(rqsbuf, sense_keys[skey]);
		return (rqsbuf);
	} else if (flag == 1) {		/* ASC/ASCQ Only */
		asc2ascii(snsbuf[12], snsbuf[13], rqsbuf);
		return (rqsbuf);
	} else  if (flag == 2) {	/* Sense Key && ASC/ASCQ */
		asc2ascii(snsbuf[12], snsbuf[13],
		    rqsbuf + sprintf(rqsbuf, "%s, ", sense_keys[skey]));
		return (rqsbuf);
	} else if (flag == 3  && snsbuf[7] >= 9 && (snsbuf[15] & 0x80)) {
		/*
		 * SKSV Data
		 */
		switch (skey) {
		case 0x5:	/* Illegal Request */
			if (snsbuf[15] & 0x8) {
				(void) sprintf(rqsbuf,
				    "Error in %s, Offset %d, bit %d",
				    (snsbuf[15] & 0x40)? "CDB" : "Parameters",
				    (snsbuf[16] & 0xff) << 8 |
				    (snsbuf[17] & 0xff), snsbuf[15] & 0xf);
			} else {
				(void) sprintf(rqsbuf,
				    "Error in %s, Offset %d",
				    (snsbuf[15] & 0x40)? "CDB" : "Parameters",
				    (snsbuf[16] & 0xff) << 8 |
				    (snsbuf[17] & 0xff));
			}
			return (rqsbuf);
		case 0x1:
		case 0x3:
		case 0x4:
			(void) sprintf(rqsbuf, "Actual Retry Count: %d",
			    (snsbuf[16] & 0xff) << 8 | (snsbuf[17] & 0xff));
			return (rqsbuf);
		case 0x2:
			(void) sprintf(rqsbuf, "Progress Indicator: %d",
			    (snsbuf[16] & 0xff) << 8 | (snsbuf[17] & 0xff));
			return (rqsbuf);
		default:
			break;
		}
	}
	return (NULL);
}

#ifdef	SCSIDEBUG
/*
 * Given a scsi_xfer, dump the request, in all it's glory
 */
void
show_scsi_xs(xs)
	struct scsi_xfer *xs;
{
	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("cmd(%p)", xs->cmd);
	printf("len(0x%x)", xs->cmdlen);
	printf("data(%p)", xs->data);
	printf("len(0x%x)", xs->datalen);
	printf("res(0x%x)", xs->resid);
	printf("err(0x%x)", xs->error);
	printf("bp(%p)", xs->bp);
	show_scsi_cmd(xs);
}

void
show_scsi_cmd(xs)
	struct scsi_xfer *xs;
{
	u_char *b = (u_char *) xs->cmd;
	int	i = 0;

	sc_print_addr(xs->sc_link);
	printf("command: ");

	if ((xs->flags & SCSI_RESET) == 0) {
		while (i < xs->cmdlen) {
			if (i)
				printf(",");
			printf("%x", b[i++]);
		}
		printf("-[%d bytes]\n", xs->datalen);
		if (xs->datalen)
			show_mem(xs->data, min(64, xs->datalen));
	} else
		printf("-RESET-\n");
}

void
show_mem(address, num)
	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 */