/*      $NetBSD: sd.c,v 1.347 2025/10/11 13:58:57 mlelstv Exp $ */

/*-
 * Copyright (c) 1998, 2003, 2004 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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)
 * for TRW Financial Systems for use under the MACH(2.5) operating system.
 *
 * TRW Financial Systems, in accordance with their agreement with Carnegie
 * Mellon University, makes this software available to CMU to distribute
 * or use in any manner that they see fit as long as this message is kept with
 * the software. For this reason TFS also grants any other persons or
 * organisations permission to use or modify this software.
 *
 * TFS supplies this software to be publicly redistributed
 * on the understanding that TFS is not responsible for the correct
 * functioning of this software in any circumstances.
 *
 * Ported to run under 386BSD by Julian Elischer (julian@dialix.oz.au)
 * Sept 1992
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: sd.c,v 1.347 2025/10/11 13:58:57 mlelstv Exp $");

#ifdef _KERNEL_OPT
#include "opt_scsi.h"
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/scsiio.h>
#include <sys/buf.h>
#include <sys/bufq.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <sys/errno.h>
#include <sys/device.h>
#include <sys/disklabel.h>
#include <sys/disk.h>
#include <sys/proc.h>
#include <sys/conf.h>
#include <sys/vnode.h>

#include <dev/scsipi/scsi_spc.h>
#include <dev/scsipi/scsipi_all.h>
#include <dev/scsipi/scsi_all.h>
#include <dev/scsipi/scsipi_disk.h>
#include <dev/scsipi/scsi_disk.h>
#include <dev/scsipi/scsiconf.h>
#include <dev/scsipi/scsipi_base.h>
#include <dev/scsipi/sdvar.h>

#include <prop/proplib.h>

#define SDUNIT(dev)                     DISKUNIT(dev)
#define SDPART(dev)                     DISKPART(dev)
#define SDMINOR(unit, part)             DISKMINOR(unit, part)
#define MAKESDDEV(maj, unit, part)      MAKEDISKDEV(maj, unit, part)

#define SDLABELDEV(dev) (MAKESDDEV(major(dev), SDUNIT(dev), RAW_PART))

#define SD_DEFAULT_BLKSIZE      512

static void     sdminphys(struct buf *);
static void     sdstart(struct scsipi_periph *);
static void     sdrestart(void *);
static void     sddone(struct scsipi_xfer *, int);
static bool     sd_suspend(device_t, const pmf_qual_t *);
static bool     sd_shutdown(device_t, int);
static int      sd_interpret_sense(struct scsipi_xfer *);
static int      sd_diskstart(device_t, struct buf *);
static int      sd_dumpblocks(device_t, void *, daddr_t, int);
static void     sd_iosize(device_t, int *);
static int      sd_lastclose(device_t);
static int      sd_firstopen(device_t, dev_t, int, int);
static void     sd_label(device_t, struct disklabel *);
static int      sd_discard(device_t, off_t, off_t);

static int      sd_mode_sense(struct sd_softc *, u_int8_t, void *, size_t, int,
                    int, int *);
static int      sd_mode_select(struct sd_softc *, u_int8_t, void *, size_t,
                    int, int);
static int      sd_validate_blksize(struct scsipi_periph *, int);
static u_int64_t sd_read_capacity(struct sd_softc *, int *, int flags);
static int      sd_get_simplifiedparms(struct sd_softc *, struct disk_parms *,
                    int);
static int      sd_get_capacity(struct sd_softc *, struct disk_parms *, int);
static int      sd_get_parms(struct sd_softc *, struct disk_parms *, int);
static int      sd_get_parms_page4(struct sd_softc *, struct disk_parms *,
                    int);
static int      sd_get_parms_page5(struct sd_softc *, struct disk_parms *,
                    int);

static int      sd_flush(struct sd_softc *, int);
static int      sd_getcache(struct sd_softc *, int *);
static int      sd_setcache(struct sd_softc *, int);

static int      sdmatch(device_t, cfdata_t, void *);
static void     sdattach(device_t, device_t, void *);
static int      sddetach(device_t, int);
static void     sd_set_geometry(struct sd_softc *);

CFATTACH_DECL3_NEW(sd, sizeof(struct sd_softc), sdmatch, sdattach, sddetach,
    NULL, NULL, NULL, DVF_DETACH_SHUTDOWN);

extern struct cfdriver sd_cd;

static const struct scsipi_inquiry_pattern sd_patterns[] = {
        {T_DIRECT, T_FIXED,
         "",         "",                 ""},
        {T_DIRECT, T_REMOV,
         "",         "",                 ""},
        {T_OPTICAL, T_FIXED,
         "",         "",                 ""},
        {T_OPTICAL, T_REMOV,
         "",         "",                 ""},
        {T_SIMPLE_DIRECT, T_FIXED,
         "",         "",                 ""},
        {T_SIMPLE_DIRECT, T_REMOV,
         "",         "",                 ""},
};

static dev_type_open(sdopen);
static dev_type_close(sdclose);
static dev_type_read(sdread);
static dev_type_write(sdwrite);
static dev_type_ioctl(sdioctl);
static dev_type_strategy(sdstrategy);
static dev_type_dump(sddump);
static dev_type_size(sdsize);
static dev_type_discard(sddiscard);

const struct bdevsw sd_bdevsw = {
        .d_open = sdopen,
        .d_close = sdclose,
        .d_strategy = sdstrategy,
        .d_ioctl = sdioctl,
        .d_dump = sddump,
        .d_psize = sdsize,
        .d_discard = sddiscard,
        .d_cfdriver = &sd_cd,
        .d_devtounit = disklabel_dev_unit,
        .d_flag = D_DISK | D_MPSAFE
};

const struct cdevsw sd_cdevsw = {
        .d_open = sdopen,
        .d_close = sdclose,
        .d_read = sdread,
        .d_write = sdwrite,
        .d_ioctl = sdioctl,
        .d_stop = nostop,
        .d_tty = notty,
        .d_poll = nopoll,
        .d_mmap = nommap,
        .d_kqfilter = nokqfilter,
        .d_discard = sddiscard,
        .d_cfdriver = &sd_cd,
        .d_devtounit = disklabel_dev_unit,
        .d_flag = D_DISK | D_MPSAFE
};

static const struct dkdriver sddkdriver = {
        .d_open = sdopen,
        .d_close = sdclose,
        .d_strategy = sdstrategy,
        .d_minphys = sdminphys,
        .d_diskstart = sd_diskstart,
        .d_dumpblocks = sd_dumpblocks,
        .d_iosize = sd_iosize,
        .d_firstopen = sd_firstopen,
        .d_lastclose = sd_lastclose,
        .d_label = sd_label,
        .d_discard = sd_discard,
};

static const struct scsipi_periphsw sd_switch = {
        sd_interpret_sense,     /* check our error handler first */
        sdstart,                /* have a queue, served by this */
        NULL,                   /* have no async handler */
        sddone,                 /* deal with stats at interrupt time */
};

struct sd_mode_sense_data {
        /*
         * XXX
         * We are not going to parse this as-is -- it just has to be large
         * enough.
         */
        union {
                struct scsi_mode_parameter_header_6 small;
                struct scsi_mode_parameter_header_10 big;
        } header;
        struct scsi_general_block_descriptor blk_desc;
        union scsi_disk_pages pages;
};

/*
 * The routine called by the low level scsi routine when it discovers
 * A device suitable for this driver
 */
static int
sdmatch(device_t parent, cfdata_t match,
    void *aux)
{
        struct scsipibus_attach_args *sa = aux;
        int priority;

        (void)scsipi_inqmatch(&sa->sa_inqbuf,
            sd_patterns, sizeof(sd_patterns) / sizeof(sd_patterns[0]),
            sizeof(sd_patterns[0]), &priority);

        return (priority);
}

/*
 * Attach routine common to atapi & scsi.
 */
static void
sdattach(device_t parent, device_t self, void *aux)
{
        struct sd_softc *sd = device_private(self);
        struct dk_softc *dksc = &sd->sc_dksc;
        struct scsipibus_attach_args *sa = aux;
        struct scsipi_periph *periph = sa->sa_periph;
        int error, result, dtype;
        struct disk_parms *dp = &sd->params;
        char pbuf[9];

        SC_DEBUG(periph, SCSIPI_DB2, ("sdattach: "));

        sd->type = (sa->sa_inqbuf.type & SID_TYPE);
        memcpy(sd->name, sa->sa_inqbuf.product, uimin(16, sizeof(sd->name)));
        memcpy(sd->typename, sa->sa_inqbuf.product,
            uimin(16, sizeof(sd->typename)));

        if (sd->type == T_SIMPLE_DIRECT) {
                periph->periph_quirks |= PQUIRK_ONLYBIG;
                periph->periph_quirks |= PQUIRK_NOBIGMODESENSE;
        }

        switch (SCSIPI_BUSTYPE_TYPE(scsipi_periph_bustype(sa->sa_periph))) {
        case SCSIPI_BUSTYPE_SCSI:
                dtype = DKTYPE_SCSI;
                if (periph->periph_version == 0)
                        sd->flags |= SDF_ANCIENT;
                break;
        case SCSIPI_BUSTYPE_ATAPI:
                dtype = DKTYPE_ATAPI;
                break;
        default:
                dtype = DKTYPE_UNKNOWN;
                break;
        }

        /* Initialize dk and disk structure. */
        dk_init(dksc, self, dtype);
        disk_init(&dksc->sc_dkdev, dksc->sc_xname, &sddkdriver);

        /* Attach dk and disk subsystems */
        dk_attach(dksc);
        disk_attach(&dksc->sc_dkdev);

        bufq_alloc(&dksc->sc_bufq, BUFQ_DISK_DEFAULT_STRAT,
            BUFQ_SORT_RAWBLOCK);

        callout_init(&sd->sc_callout, 0);

        /*
         * Store information needed to contact our base driver
         */
        sd->sc_periph = periph;

        periph->periph_dev = dksc->sc_dev;
        periph->periph_switch = &sd_switch;

        /*
         * Increase our openings to the maximum-per-periph
         * supported by the adapter.  This will either be
         * clamped down or grown by the adapter if necessary.
         */
        periph->periph_openings =
            SCSIPI_CHAN_MAX_PERIPH(periph->periph_channel);
        periph->periph_flags |= PERIPH_GROW_OPENINGS;

        /*
         * Use the subdriver to request information regarding the drive.
         */
        aprint_naive("\n");
        aprint_normal("\n");

        if (periph->periph_quirks & PQUIRK_START)
                (void)scsipi_start(periph, SSS_START, XS_CTL_SILENT);

        error = scsipi_test_unit_ready(periph,
            XS_CTL_DISCOVERY | XS_CTL_IGNORE_ILLEGAL_REQUEST |
            XS_CTL_IGNORE_MEDIA_CHANGE | XS_CTL_SILENT_NODEV);
        if (error)
                result = SDGP_RESULT_OFFLINE;
        else
                result = sd_get_parms(sd, &sd->params, XS_CTL_DISCOVERY);

        aprint_normal_dev(dksc->sc_dev, "");
        switch (result) {
        case SDGP_RESULT_OK:
                format_bytes(pbuf, sizeof(pbuf),
                    (u_int64_t)dp->disksize * dp->blksize);
                aprint_normal("%s, %ld cyl, %ld head, %ld sec, %ld bytes/sect"
                    " x %llu sectors",
                    pbuf, dp->cyls, dp->heads, dp->sectors, dp->blksize,
                    (unsigned long long)dp->disksize);
                if (dp->lbppbe) {
                        aprint_normal(" (%lu bytes/physsect", dp->blksize <<
                            dp->lbppbe);
                        if (dp->lalba)
                                aprint_normal("; first aligned sector %u",
                                    dp->lalba);
                        aprint_normal(")");
                }
                break;

        case SDGP_RESULT_OFFLINE:
                aprint_normal("drive offline");
                break;

        case SDGP_RESULT_UNFORMATTED:
                aprint_normal("unformatted media");
                break;

#ifdef DIAGNOSTIC
        default:
                panic("sdattach: unknown result from get_parms");
                break;
#endif
        }
        aprint_normal("\n");

        /* Discover wedges on this disk if it is online */
        if (result == SDGP_RESULT_OK)
                dkwedge_discover(&dksc->sc_dkdev);

        /*
         * Establish a shutdown hook so that we can ensure that
         * our data has actually made it onto the platter at
         * shutdown time.  Note that this relies on the fact
         * that the shutdown hooks at the "leaves" of the device tree
         * are run, first (thus guaranteeing that our hook runs before
         * our ancestors').
         */
        if (!pmf_device_register1(self, sd_suspend, NULL, sd_shutdown))
                aprint_error_dev(self, "couldn't establish power handler\n");
}

static int
sddetach(device_t self, int flags)
{
        struct sd_softc *sd = device_private(self);
        struct dk_softc *dksc = &sd->sc_dksc;
        struct scsipi_periph *periph = sd->sc_periph;
        struct scsipi_channel *chan = periph->periph_channel;
        int bmaj, cmaj, i, mn, rc;

        rc = disk_begindetach(&dksc->sc_dkdev, sd_lastclose, self, flags);
        if (rc)
                return rc;

        /* locate the major number */
        bmaj = bdevsw_lookup_major(&sd_bdevsw);
        cmaj = cdevsw_lookup_major(&sd_cdevsw);

        /* Nuke the vnodes for any open instances */
        for (i = 0; i < MAXPARTITIONS; i++) {
                mn = SDMINOR(device_unit(self), i);
                vdevgone(bmaj, mn, mn, VBLK);
                vdevgone(cmaj, mn, mn, VCHR);
        }

        /* kill any pending restart */
        callout_halt(&sd->sc_callout, NULL);

        dk_drain(dksc);

        /* Kill off any pending commands. */
        mutex_enter(chan_mtx(chan));
        scsipi_kill_pending(periph);
        mutex_exit(chan_mtx(chan));

        bufq_free(dksc->sc_bufq);

        /* Delete all of our wedges. */
        dkwedge_delall(&dksc->sc_dkdev);

        /* Detach from the disk list. */
        disk_detach(&dksc->sc_dkdev);
        disk_destroy(&dksc->sc_dkdev);

        dk_detach(dksc);

        callout_destroy(&sd->sc_callout);

        pmf_device_deregister(self);

        return (0);
}

/*
 * Serialized by caller
 */
static int
sd_firstopen(device_t self, dev_t dev, int flag, int fmt)
{
        struct sd_softc *sd = device_private(self);
        struct scsipi_periph *periph = sd->sc_periph;
        struct scsipi_adapter *adapt = periph->periph_channel->chan_adapter;
        int error, silent;
        int part, removable;

        part = SDPART(dev);

        error = scsipi_adapter_addref(adapt);
        if (error)
                return error;

        if ((part == RAW_PART && fmt == S_IFCHR) || (flag & FSILENT))
                silent = XS_CTL_SILENT;
        else
                silent = 0;

        /* Check that it is still responding and ok. */
        error = scsipi_test_unit_ready(periph,
            XS_CTL_IGNORE_ILLEGAL_REQUEST | XS_CTL_IGNORE_MEDIA_CHANGE |
            silent);

        /*
         * Start the pack spinning if necessary. Always allow the
         * raw partition to be opened, for raw IOCTLs. Data transfers
         * will check for SDEV_MEDIA_LOADED.
         */
        if (error == EIO) {
                error = scsipi_start(periph, SSS_START, silent);
                if (error == EINVAL)
                        error = EIO;
        }
        if (error)
                goto bad;

        removable = (periph->periph_flags & PERIPH_REMOVABLE) != 0;
        if (removable) {
                /* Lock the pack in. */
                error = scsipi_prevent(periph, SPAMR_PREVENT_DT,
                    XS_CTL_IGNORE_ILLEGAL_REQUEST |
                    XS_CTL_IGNORE_MEDIA_CHANGE |
                    XS_CTL_SILENT);
                if (error)
                        goto bad;
        }

        if ((periph->periph_flags & PERIPH_MEDIA_LOADED) == 0) {
                int param_error;

                /*
                 * Load the physical device parameters.
                 *
                 * Note that if media is present but unformatted,
                 * we allow the open (so that it can be formatted!).
                 * The drive should refuse real I/O, if the media is
                 * unformatted.
                 */
                param_error = sd_get_parms(sd, &sd->params, 0);
                if (param_error == SDGP_RESULT_OFFLINE) {
                        error = ENXIO;
                        goto bad2;
                }
                periph->periph_flags |= PERIPH_MEDIA_LOADED;

                SC_DEBUG(periph, SCSIPI_DB3, ("Params loaded "));
        }

        periph->periph_flags |= PERIPH_OPEN;
        return 0;

bad2:
        if (removable)
                scsipi_prevent(periph, SPAMR_ALLOW,
                    XS_CTL_IGNORE_ILLEGAL_REQUEST |
                    XS_CTL_IGNORE_MEDIA_CHANGE |
                    XS_CTL_SILENT);

bad:
        scsipi_adapter_delref(adapt);
        return error;
}

/*
 * open the device. Make sure the partition info is a up-to-date as can be.
 */
static int
sdopen(dev_t dev, int flag, int fmt, struct lwp *l)
{
        struct sd_softc *sd;
        struct dk_softc *dksc;
        struct scsipi_periph *periph;
        int unit, part;
        int error;

        unit = SDUNIT(dev);
        sd = device_lookup_private(&sd_cd, unit);
        if (sd == NULL)
                return (ENXIO);
        dksc = &sd->sc_dksc;

        if (!device_is_active(dksc->sc_dev))
                return (ENODEV);

        periph = sd->sc_periph;
        part = SDPART(dev);

        SC_DEBUG(periph, SCSIPI_DB1,
            ("sdopen: dev=0x%"PRIx64" (unit %d (of %d), partition %d)\n",
            dev, unit, sd_cd.cd_ndevs, SDPART(dev)));

        /*
         * If any partition is open, but the disk has been invalidated,
         * disallow further opens of non-raw partition
         */
        if ((periph->periph_flags & (PERIPH_OPEN | PERIPH_MEDIA_LOADED)) ==
            PERIPH_OPEN) {
                if (part != RAW_PART || fmt != S_IFCHR)
                        return EIO;
        }

        error = dk_open(dksc, dev, flag, fmt, l);

        SC_DEBUG(periph, SCSIPI_DB3, ("open complete\n"));

        return error;
}

/*
 * Serialized by caller
 */
static int
sd_lastclose(device_t self)
{
        struct sd_softc *sd = device_private(self);
        struct dk_softc *dksc = &sd->sc_dksc;
        struct scsipi_periph *periph = sd->sc_periph;
        struct scsipi_adapter *adapt = periph->periph_channel->chan_adapter;

        /*
         * If the disk cache needs flushing, and the disk supports
         * it, do it now.
         */
        if ((sd->flags & SDF_DIRTY) != 0) {
                if (sd_flush(sd, 0)) {
                        aprint_error_dev(dksc->sc_dev,
                                "cache synchronization failed\n");
                        sd->flags &= ~SDF_FLUSHING;
                } else
                        sd->flags &= ~(SDF_FLUSHING|SDF_DIRTY);
        }

        scsipi_wait_drain(periph);

        if (periph->periph_flags & PERIPH_REMOVABLE)
                scsipi_prevent(periph, SPAMR_ALLOW,
                    XS_CTL_IGNORE_ILLEGAL_REQUEST |
                    XS_CTL_IGNORE_NOT_READY |
                    XS_CTL_SILENT);
        periph->periph_flags &= ~PERIPH_OPEN;

        scsipi_wait_drain(periph);

        scsipi_adapter_delref(adapt);

        return 0;
}

/*
 * close the device.. only called if we are the LAST occurrence of an open
 * device.  Convenient now but usually a pain.
 */
static int
sdclose(dev_t dev, int flag, int fmt, struct lwp *l)
{
        struct sd_softc *sd;
        struct dk_softc *dksc;
        int unit;

        unit = SDUNIT(dev);
        sd = device_lookup_private(&sd_cd, unit);
        dksc = &sd->sc_dksc;

        return dk_close(dksc, dev, flag, fmt, l);
}

/*
 * Actually translate the requested transfer into one the physical driver
 * can understand.  The transfer is described by a buf and will include
 * only one physical transfer.
 */
static void
sdstrategy(struct buf *bp)
{
        struct sd_softc *sd = device_lookup_private(&sd_cd, SDUNIT(bp->b_dev));
        struct dk_softc *dksc = &sd->sc_dksc;
        struct scsipi_periph *periph = sd->sc_periph;

        SC_DEBUG(sd->sc_periph, SCSIPI_DB2, ("sdstrategy "));
        SC_DEBUG(sd->sc_periph, SCSIPI_DB1,
            ("%d bytes @ blk %" PRId64 "\n", bp->b_bcount, bp->b_blkno));

        /*
         * If the device has been made invalid, error out
         */
        if ((periph->periph_flags & PERIPH_MEDIA_LOADED) == 0 ||
            !device_is_active(dksc->sc_dev)) {
                if (periph->periph_flags & PERIPH_OPEN)
                        bp->b_error = EIO;
                else
                        bp->b_error = ENODEV;

                bp->b_resid = bp->b_bcount;
                biodone(bp);
                return;
        }

        dk_strategy(dksc, bp);
}

/*
 * Issue single I/O command
 *
 * Called from dk_start and implicitly from dk_strategy
 */
static int
sd_diskstart(device_t dev, struct buf *bp)
{
        struct sd_softc *sd = device_private(dev);
        struct scsipi_periph *periph = sd->sc_periph;
        struct scsipi_channel *chan = periph->periph_channel;
        struct scsipi_rw_16 cmd16;
        struct scsipi_rw_10 cmd_big;
        struct scsi_rw_6 cmd_small;
        struct scsipi_generic *cmdp;
        struct scsipi_xfer *xs;
        int error, flags, nblks, cmdlen;
        int cdb_flags;
        bool havefua = !(periph->periph_quirks & PQUIRK_NOFUA);

        mutex_enter(chan_mtx(chan));

        if (periph->periph_active >= periph->periph_openings) {
                error = EAGAIN;
                goto out;
        }

        /*
         * there is excess capacity, but a special waits
         * It'll need the adapter as soon as we clear out of the
         * way and let it run (user level wait).
         */
        if (periph->periph_flags & PERIPH_WAITING) {
                periph->periph_flags &= ~PERIPH_WAITING;
                cv_broadcast(periph_cv_periph(periph));
                error = EAGAIN;
                goto out;
        }

        /*
         * If the device has become invalid, abort all the
         * reads and writes until all files have been closed and
         * re-opened.
         */
        if (__predict_false(
            (periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)) {
                error = EIO;
                goto out;
        }

        /*
         * Mark the disk dirty so that the cache will be
         * flushed on close.
         */
        if ((bp->b_flags & B_READ) == 0)
                sd->flags |= SDF_DIRTY;

        if (sd->params.blksize == DEV_BSIZE)
                nblks = bp->b_bcount >> DEV_BSHIFT;
        else
                nblks = howmany(bp->b_bcount, sd->params.blksize);

        /*
         * Pass FUA and/or DPO if requested. Must be done before CDB
         * selection, as 6-byte CDB doesn't support the flags.
         */
        cdb_flags = 0;
        if (havefua) {
                if (bp->b_flags & B_MEDIA_FUA)
                        cdb_flags |= SRWB_FUA;

                if (bp->b_flags & B_MEDIA_DPO)
                        cdb_flags |= SRWB_DPO;
        }

        /*
         * Fill out the scsi command.  Use the smallest CDB possible
         * (6-byte, 10-byte, or 16-byte). If we need FUA or DPO,
         * need to use 10-byte or bigger, as the 6-byte doesn't support
         * the flags.
         */
        if (((bp->b_rawblkno & 0x1fffff) == bp->b_rawblkno) &&
            ((nblks & 0xff) == nblks) &&
            !(periph->periph_quirks & PQUIRK_ONLYBIG) &&
            !cdb_flags) {
                /* 6-byte CDB */
                memset(&cmd_small, 0, sizeof(cmd_small));
                cmd_small.opcode = (bp->b_flags & B_READ) ?
                    SCSI_READ_6_COMMAND : SCSI_WRITE_6_COMMAND;
                _lto3b(bp->b_rawblkno, cmd_small.addr);
                cmd_small.length = nblks & 0xff;
                cmdlen = sizeof(cmd_small);
                cmdp = (struct scsipi_generic *)&cmd_small;
        } else if ((bp->b_rawblkno & 0xffffffff) == bp->b_rawblkno) {
                /* 10-byte CDB */
                memset(&cmd_big, 0, sizeof(cmd_big));
                cmd_big.opcode = (bp->b_flags & B_READ) ?
                    READ_10 : WRITE_10;
                _lto4b(bp->b_rawblkno, cmd_big.addr);
                _lto2b(nblks, cmd_big.length);
                cmdlen = sizeof(cmd_big);
                cmdp = (struct scsipi_generic *)&cmd_big;
        } else {
                /* 16-byte CDB */
                memset(&cmd16, 0, sizeof(cmd16));
                cmd16.opcode = (bp->b_flags & B_READ) ?
                    READ_16 : WRITE_16;
                _lto8b(bp->b_rawblkno, cmd16.addr);
                _lto4b(nblks, cmd16.length);
                cmdlen = sizeof(cmd16);
                cmdp = (struct scsipi_generic *)&cmd16;
        }

        if (cdb_flags)
                cmdp->bytes[0] = cdb_flags;

        /*
         * Figure out what flags to use.
         */
        flags = XS_CTL_NOSLEEP|XS_CTL_ASYNC|XS_CTL_SIMPLE_TAG;
        if (bp->b_flags & B_READ)
                flags |= XS_CTL_DATA_IN;
        else
                flags |= XS_CTL_DATA_OUT;

        /*
         * Call the routine that chats with the adapter.
         * Note: we cannot sleep as we may be an interrupt
         */
        xs = scsipi_make_xs_locked(periph, cmdp, cmdlen,
            (u_char *)bp->b_data, bp->b_bcount,
            SDRETRIES, SD_IO_TIMEOUT, bp, flags);
        if (__predict_false(xs == NULL)) {
                /*
                 * out of memory. Keep this buffer in the queue, and
                 * retry later.
                 */
                callout_reset(&sd->sc_callout, hz / 2, sdrestart, sd);
                error = EAGAIN;
                goto out;
        }

        error = scsipi_execute_xs(xs);
        /* with a scsipi_xfer preallocated, scsipi_command can't fail */
        KASSERT(error == 0);

out:
        mutex_exit(chan_mtx(chan));

        return error;
}

/*
 * Recover I/O request after memory shortage
 *
 * Called from callout
 */
static void
sdrestart(void *v)
{
        struct sd_softc *sd = v;
        struct dk_softc *dksc = &sd->sc_dksc;

        dk_start(dksc, NULL);
}

/*
 * Recover I/O request after memory shortage
 *
 * Called from scsipi midlayer when resources have been freed
 * with channel lock held
 */
static void
sdstart(struct scsipi_periph *periph)
{
        struct sd_softc *sd = device_private(periph->periph_dev);
        struct dk_softc *dksc = &sd->sc_dksc;
        struct scsipi_channel *chan = periph->periph_channel;

        /*
         * release channel lock as dk_start may need to acquire
         * other locks
         *
         * sdstart is called from scsipi_put_xs and all its callers
         * release the lock afterwards. So releasing it here
         * doesn't matter.
         */
        mutex_exit(chan_mtx(chan));

        dk_start(dksc, NULL);

        mutex_enter(chan_mtx(chan));
}

static void
sddone(struct scsipi_xfer *xs, int error)
{
        struct sd_softc *sd = device_private(xs->xs_periph->periph_dev);
        struct dk_softc *dksc = &sd->sc_dksc;
        struct buf *bp = xs->bp;

        if (sd->flags & SDF_FLUSHING) {
                /* Flush completed, no longer dirty. */
                sd->flags &= ~(SDF_FLUSHING|SDF_DIRTY);
        }

        if (bp) {
                bp->b_error = error;
                bp->b_resid = xs->resid;
                if (error) {
                        /* on a read/write error bp->b_resid is zero, so fix */
                        bp->b_resid = bp->b_bcount;
                }

                dk_done(dksc, bp);
                /* dk_start is called from scsipi_complete */
        }
}

static void
sdminphys(struct buf *bp)
{
        struct sd_softc *sd = device_lookup_private(&sd_cd, SDUNIT(bp->b_dev));
        struct dk_softc *dksc = &sd->sc_dksc;
        long xmax;

        /*
         * If the device is ancient, we want to make sure that
         * the transfer fits into a 6-byte cdb.
         *
         * XXX Note that the SCSI-I spec says that 256-block transfers
         * are allowed in a 6-byte read/write, and are specified
         * by setting the "length" to 0.  However, we're conservative
         * here, allowing only 255-block transfers in case an
         * ancient device gets confused by length == 0.  A length of 0
         * in a 10-byte read/write actually means 0 blocks.
         */
        if ((sd->flags & SDF_ANCIENT) &&
            ((sd->sc_periph->periph_flags &
            (PERIPH_REMOVABLE | PERIPH_MEDIA_LOADED)) != PERIPH_REMOVABLE)) {
                xmax = dksc->sc_dkdev.dk_geom.dg_secsize * 0xff;

                if (bp->b_bcount > xmax)
                        bp->b_bcount = xmax;
        }

        scsipi_adapter_minphys(sd->sc_periph->periph_channel, bp);
}

static void
sd_iosize(device_t dev, int *count)
{
        struct buf B;
        int bmaj;

        bmaj       = bdevsw_lookup_major(&sd_bdevsw);
        B.b_dev    = MAKESDDEV(bmaj,device_unit(dev),RAW_PART);
        B.b_bcount = *count;

        sdminphys(&B);

        *count = B.b_bcount;
}

static int
sdread(dev_t dev, struct uio *uio, int ioflag)
{

        return (physio(sdstrategy, NULL, dev, B_READ, sdminphys, uio));
}

static int
sdwrite(dev_t dev, struct uio *uio, int ioflag)
{

        return (physio(sdstrategy, NULL, dev, B_WRITE, sdminphys, uio));
}

/*
 * Perform special action on behalf of the user
 * Knows about the internals of this device
 */
static int
sdioctl(dev_t dev, u_long cmd, void *addr, int flag, struct lwp *l)
{
        struct sd_softc *sd = device_lookup_private(&sd_cd, SDUNIT(dev));
        struct dk_softc *dksc = &sd->sc_dksc;
        struct scsipi_periph *periph = sd->sc_periph;

        int part = SDPART(dev);
        int error;

        SC_DEBUG(sd->sc_periph, SCSIPI_DB2, ("sdioctl 0x%lx ", cmd));

        /*
         * If the device is not valid, some IOCTLs can still be
         * handled on the raw partition. Check this here.
         */
        if ((periph->periph_flags & PERIPH_MEDIA_LOADED) == 0 &&
            part != RAW_PART)
                return (EIO);

        switch (cmd) {
        case DIOCLOCK:
                if (periph->periph_flags & PERIPH_REMOVABLE)
                        return (scsipi_prevent(periph,
                            (*(int *)addr) ?
                            SPAMR_PREVENT_DT : SPAMR_ALLOW, 0));
                else
                        return (ENOTTY);

        case DIOCEJECT:
                if ((periph->periph_flags & PERIPH_REMOVABLE) == 0)
                        return (ENOTTY);
                if (*(int *)addr == 0) {
                        int pmask = __BIT(part);
                        /*
                         * Don't force eject: check that we are the only
                         * partition open. If so, unlock it.
                         */
                        if (DK_BUSY(dksc, pmask) == 0) {
                                error = scsipi_prevent(periph, SPAMR_ALLOW,
                                    XS_CTL_IGNORE_NOT_READY);
                                if (error)
                                        return (error);
                        } else {
                                return (EBUSY);
                        }
                }
                /* FALLTHROUGH */
        case ODIOCEJECT:
                return ((periph->periph_flags & PERIPH_REMOVABLE) == 0 ?
                    ENOTTY : scsipi_start(periph, SSS_STOP|SSS_LOEJ, 0));

        case DIOCGCACHE:
                return (sd_getcache(sd, (int *) addr));

        case DIOCSCACHE:
                if ((flag & FWRITE) == 0)
                        return (EBADF);
                return (sd_setcache(sd, *(int *) addr));

        case DIOCCACHESYNC:
                /*
                 * XXX Do we really need to care about having a writable
                 * file descriptor here?
                 */
                if ((flag & FWRITE) == 0)
                        return (EBADF);
                if (((sd->flags & SDF_DIRTY) != 0 || *(int *)addr != 0)) {
                        error = sd_flush(sd, 0);
                        if (error) {
                                sd->flags &= ~SDF_FLUSHING;
                                return (error);
                        }
                        sd->flags &= ~(SDF_FLUSHING|SDF_DIRTY);
                }
                return (0);

        default:
                error = dk_ioctl(dksc, dev, cmd, addr, flag, l);
                if (error == ENOTTY) {
                        error = scsipi_do_ioctl(periph, dev, cmd, addr, flag,
                            l);
                }
                return (error);
        }

#ifdef DIAGNOSTIC
        panic("sdioctl: impossible");
#endif
}

static void
sd_label(device_t self, struct disklabel *lp)
{
        struct sd_softc *sd = device_private(self);

        strncpy(lp->d_typename, sd->name, 16);
        lp->d_rpm = sd->params.rot_rate;
        if (sd->sc_periph->periph_flags & PERIPH_REMOVABLE)
                lp->d_flags |= D_REMOVABLE;
}

static int
sd_unmap(struct sd_softc *sd, off_t pos, off_t len)
{
        struct scsi_unmap_10 cmd;
        struct scsi_unmap_10_data data;
        int flags = 0;
        uint64_t bno;
        uint32_t size;

        /* round the start up and the end down */
        bno = (pos + sd->params.blksize - 1) / sd->params.blksize;
        size = ((pos + len) / sd->params.blksize) - bno;

        if (size == 0)
                return 0;

        memset(&data, 0, sizeof(data));
        _lto2b(sizeof(data) - 2, data.unmap_data_length);
        _lto2b(sizeof(data) - 8, data.unmap_block_descriptor_data_length);
        _lto8b(bno, data.unmap_block_descriptor[0].addr);
        _lto4b(size, data.unmap_block_descriptor[0].len);

        memset(&cmd, 0, sizeof(cmd));
        cmd.opcode = UNMAP_10;
        cmd.byte2 = 0;
        _lto2b(sizeof(data), cmd.length);

        scsipi_command(sd->sc_periph,
            (void *)&cmd, sizeof(cmd), (void *)&data, sizeof(data),
            SDRETRIES, 2000000, NULL,
            flags | XS_CTL_DATA_OUT);

        return 0;
}

static int
sd_discard(device_t self, off_t pos, off_t len)
{
        struct sd_softc *sd = device_private(self);
        if (sd->flags & SDF_LBPU) {
                return sd_unmap(sd, pos, len);
        }
        return ENODEV;
}

static bool
sd_shutdown(device_t self, int how)
{
        struct sd_softc *sd = device_private(self);
        struct dk_softc *dksc = &sd->sc_dksc;

        /*
         * If the disk cache needs to be flushed, and the disk supports
         * it, flush it.  We're cold at this point, so we poll for
         * completion.
         */
        if ((sd->flags & SDF_DIRTY) != 0) {
                if (sd_flush(sd, XS_CTL_NOSLEEP|XS_CTL_POLL)) {
                        aprint_error_dev(dksc->sc_dev,
                                "cache synchronization failed\n");
                        sd->flags &= ~SDF_FLUSHING;
                } else
                        sd->flags &= ~(SDF_FLUSHING|SDF_DIRTY);
        }
        return true;
}

static bool
sd_suspend(device_t dv, const pmf_qual_t *qual)
{
        return sd_shutdown(dv, boothowto); /* XXX no need to poll */
}

/*
 * Check Errors
 */
static int
sd_interpret_sense(struct scsipi_xfer *xs)
{
        struct scsipi_periph *periph = xs->xs_periph;
        struct scsipi_channel *chan = periph->periph_channel;
        struct scsi_sense_data *sense = &xs->sense.scsi_sense;
        struct sd_softc *sd = device_private(periph->periph_dev);
        struct dk_softc *dksc = &sd->sc_dksc;
        int error, retval = EJUSTRETURN;

        /*
         * If the periph is already recovering, just do the normal
         * error processing.
         */
        if (periph->periph_flags & PERIPH_RECOVERING)
                return (retval);

        /*
         * Ignore errors from accessing illegal fields (e.g. trying to
         * lock the door of a digicam, which doesn't have a door that
         * can be locked) for the SCSI_PREVENT_ALLOW_MEDIUM_REMOVAL command.
         */
        if (xs->cmd->opcode == SCSI_PREVENT_ALLOW_MEDIUM_REMOVAL &&
            SSD_SENSE_KEY(sense->flags) == SKEY_ILLEGAL_REQUEST &&
            sense->asc == 0x24 &&
            sense->ascq == 0x00) { /* Illegal field in CDB */
                if (!(xs->xs_control & XS_CTL_SILENT)) {
                        scsipi_printaddr(periph);
                        printf("no door lock\n");
                }
                xs->xs_control |= XS_CTL_IGNORE_ILLEGAL_REQUEST;
                return (retval);
        }

        /*
         * If it isn't a extended or extended/deferred error, let
         * the generic code handle it.
         */
        if (SSD_RCODE(sense->response_code) != SSD_RCODE_CURRENT &&
            SSD_RCODE(sense->response_code) != SSD_RCODE_DEFERRED)
                return (retval);

        if (SSD_SENSE_KEY(sense->flags) == SKEY_NOT_READY &&
            sense->asc == 0x4) {
                if (sense->ascq == 0x01)        {
                        /*
                         * Unit In The Process Of Becoming Ready.
                         */
                        printf("%s: waiting for pack to spin up...\n",
                            dksc->sc_xname);
                        if (!callout_pending(&periph->periph_callout))
                                scsipi_periph_freeze(periph, 1);
                        callout_reset(&periph->periph_callout,
                            5 * hz, scsipi_periph_timed_thaw, periph);
                        retval = ERESTART;
                } else if (sense->ascq == 0x02) {
                        printf("%s: pack is stopped, restarting...\n",
                            dksc->sc_xname);
                        mutex_enter(chan_mtx(chan));
                        periph->periph_flags |= PERIPH_RECOVERING;
                        mutex_exit(chan_mtx(chan));
                        error = scsipi_start(periph, SSS_START,
                            XS_CTL_URGENT|XS_CTL_HEAD_TAG|
                            XS_CTL_THAW_PERIPH|XS_CTL_FREEZE_PERIPH);
                        if (error) {
                                aprint_error_dev(dksc->sc_dev,
                                        "unable to restart pack\n");
                                retval = error;
                        } else
                                retval = ERESTART;
                        mutex_enter(chan_mtx(chan));
                        periph->periph_flags &= ~PERIPH_RECOVERING;
                        mutex_exit(chan_mtx(chan));
                }
        }
        if (SSD_SENSE_KEY(sense->flags) == SKEY_MEDIUM_ERROR &&
            sense->asc == 0x31 &&
            sense->ascq == 0x00)        { /* maybe for any asq ? */
                /* Medium Format Corrupted */
                retval = EFTYPE;
        }
        return (retval);
}


static int
sdsize(dev_t dev)
{
        struct sd_softc *sd;
        struct dk_softc *dksc;
        int unit;

        unit = SDUNIT(dev);
        sd = device_lookup_private(&sd_cd, unit);
        if (sd == NULL)
                return (-1);
        dksc = &sd->sc_dksc;

        if (!device_is_active(dksc->sc_dev))
                return (-1);

        return dk_size(dksc, dev);
}

/* #define SD_DUMP_NOT_TRUSTED if you just want to watch */
static struct scsipi_xfer sx;

/*
 * dump all of physical memory into the partition specified, starting
 * at offset 'dumplo' into the partition.
 */
static int
sddump(dev_t dev, daddr_t blkno, void *va, size_t size)
{
        struct sd_softc *sd;
        struct dk_softc *dksc;
        struct scsipi_periph *periph;
        int unit;

        unit = SDUNIT(dev);
        if ((sd = device_lookup_private(&sd_cd, unit)) == NULL)
                return (ENXIO);
        dksc = &sd->sc_dksc;

        if (!device_is_active(dksc->sc_dev))
                return (ENODEV);

        periph = sd->sc_periph;

        /* Make sure it was initialized. */
        if ((periph->periph_flags & PERIPH_MEDIA_LOADED) == 0)
                return (ENXIO);

        return dk_dump(dksc, dev, blkno, va, size, 0);
}

static int
sd_dumpblocks(device_t dev, void *va, daddr_t blkno, int nblk)
{
        struct sd_softc *sd = device_private(dev);
        struct dk_softc *dksc = &sd->sc_dksc;
        struct disk_geom *dg = &dksc->sc_dkdev.dk_geom;
        struct scsipi_rw_10 cmd;        /* write command */
        struct scsipi_rw_16 cmd16;      /* write command */
        struct scsipi_generic *cmdp;
        struct scsipi_xfer *xs;         /* ... convenience */
        struct scsipi_periph *periph;
        struct scsipi_channel *chan;
        size_t sectorsize;
        int cmdlen;

        periph = sd->sc_periph;
        chan = periph->periph_channel;

        sectorsize = dg->dg_secsize;

        xs = &sx;

#ifndef SD_DUMP_NOT_TRUSTED
        /*
         *  Fill out the scsi command
         */
        if ((blkno & 0xffffffff) == blkno) {
                memset(&cmd, 0, sizeof(cmd));
                cmd.opcode = WRITE_10;
                _lto4b(blkno, cmd.addr);
                _lto2b(nblk, cmd.length);
                cmdlen = sizeof(cmd);
                cmdp = (struct scsipi_generic *)&cmd;
        } else {
                memset(&cmd16, 0, sizeof(cmd16));
                cmd16.opcode = WRITE_16;
                _lto8b(blkno, cmd16.addr);
                _lto4b(nblk, cmd16.length);
                cmdlen = sizeof(cmd16);
                cmdp = (struct scsipi_generic *)&cmd16;
        }

        /*
         * Fill out the scsipi_xfer structure
         *    Note: we cannot sleep as we may be an interrupt
         * don't use scsipi_command() as it may want to wait
         * for an xs.
         */
        memset(xs, 0, sizeof(sx));
        xs->xs_control |= XS_CTL_NOSLEEP | XS_CTL_POLL |
            XS_CTL_DATA_OUT;
        xs->xs_status = 0;
        xs->xs_periph = periph;
        xs->xs_retries = SDRETRIES;
        xs->timeout = 10000;    /* 10000 millisecs for a disk ! */
        xs->cmd = cmdp;
        xs->cmdlen = cmdlen;
        xs->resid = nblk * sectorsize;
        xs->error = XS_NOERROR;
        xs->bp = 0;
        xs->data = va;
        xs->datalen = nblk * sectorsize;
        callout_init(&xs->xs_callout, 0);

        /*
         * Pass all this info to the scsi driver.
         */
        scsipi_adapter_request(chan, ADAPTER_REQ_RUN_XFER, xs);
        if ((xs->xs_status & XS_STS_DONE) == 0 ||
            xs->error != XS_NOERROR)
                return (EIO);
#else   /* SD_DUMP_NOT_TRUSTED */
        /* Let's just talk about this first... */
        printf("sd%d: dump addr 0x%x, blk %d\n", unit, va, blkno);
        delay(500 * 1000);      /* half a second */
#endif  /* SD_DUMP_NOT_TRUSTED */

        return (0);
}

static int
sd_mode_sense(struct sd_softc *sd, u_int8_t byte2, void *sense, size_t size,
    int page, int flags, int *big)
{

        if ((sd->sc_periph->periph_quirks & PQUIRK_ONLYBIG) &&
            !(sd->sc_periph->periph_quirks & PQUIRK_NOBIGMODESENSE)) {
                *big = 1;
                return scsipi_mode_sense_big(sd->sc_periph, byte2, page, sense,
                    size + sizeof(struct scsi_mode_parameter_header_10),
                    flags, SDRETRIES, 6000);
        } else {
                *big = 0;
                return scsipi_mode_sense(sd->sc_periph, byte2, page, sense,
                    size + sizeof(struct scsi_mode_parameter_header_6),
                    flags, SDRETRIES, 6000);
        }
}

static int
sd_mode_select(struct sd_softc *sd, u_int8_t byte2, void *sense, size_t size,
    int flags, int big)
{

        if (big) {
                struct scsi_mode_parameter_header_10 *header = sense;

                _lto2b(0, header->data_length);
                return scsipi_mode_select_big(sd->sc_periph, byte2, sense,
                    size + sizeof(struct scsi_mode_parameter_header_10),
                    flags, SDRETRIES, 6000);
        } else {
                struct scsi_mode_parameter_header_6 *header = sense;

                header->data_length = 0;
                return scsipi_mode_select(sd->sc_periph, byte2, sense,
                    size + sizeof(struct scsi_mode_parameter_header_6),
                    flags, SDRETRIES, 6000);
        }
}

/*
 * sd_validate_blksize:
 *
 *      Validate the block size.  Print error if periph is specified,
 */
static int
sd_validate_blksize(struct scsipi_periph *periph, int len)
{

        if (len >= 256 && powerof2(len) && len <= MAXPHYS) {
                return 1;
        }

        if (periph) {
                scsipi_printaddr(periph);
                printf("%s sector size: 0x%x.  Defaulting to %d bytes.\n",
                    !powerof2(len) ?
                    "preposterous" : "unsupported",
                    len, SD_DEFAULT_BLKSIZE);
        }

        return 0;
}

/*
 * sd_read_capacity:
 *
 *      Find out from the device what its capacity is.
 */
static u_int64_t
sd_read_capacity(struct sd_softc *sd, int *blksize, int flags)
{
        struct scsipi_periph *periph = sd->sc_periph;
        union {
                struct scsipi_read_capacity_10 cmd;
                struct scsipi_read_capacity_16 cmd16;
        } cmd;
        union {
                struct scsipi_read_capacity_10_data data;
                struct scsipi_read_capacity_16_data data16;
        } *datap;
        uint64_t rv;

        sd->params.lbppbe = 0;
        sd->params.lalba = 0;
        sd->flags &= ~SDF_LBPME;

        /*
         * Don't allocate data buffer on stack;
         * The lower driver layer might use the same stack and
         * if it uses region which is in the same cacheline,
         * cache flush ops against the data buffer won't work properly.
         */
        datap = malloc(sizeof(*datap), M_TEMP, M_WAITOK);
        if (datap == NULL)
                return 0;

        rv = 0;

        /*
         * When device announces SPC-3 conformance,
         * try READ CAPACITY (16) to collect information
         * about physical blocks and management capabilities.
         *
         * Fall back to READ CAPACITY (10).
         */

        memset(&cmd, 0, sizeof(cmd));
        cmd.cmd16.opcode = READ_CAPACITY_16;
        cmd.cmd16.byte2 = SRC16_SERVICE_ACTION;
        _lto4b(sizeof(datap->data16), cmd.cmd16.len);

        memset(datap, 0, sizeof(datap->data16));
        if (periph->periph_version >= 5 &&
            scsipi_command(periph, (void *)&cmd.cmd16, sizeof(cmd.cmd16),
            (void *)datap, sizeof(datap->data16), SCSIPIRETRIES, 20000,
            NULL, flags | XS_CTL_DATA_IN | XS_CTL_SILENT) == 0) {

                *blksize = _4btol(datap->data16.length);
                rv = _8btol(datap->data16.addr) + 1;

                sd->params.lbppbe = datap->data16.byte14
                    & SRC16D_LBPPB_EXPONENT;
                sd->params.lalba = _2btol(datap->data16.lowest_aligned)
                    & SRC16D_LALBA;
                if (_2btol(datap->data16.lowest_aligned) & SRC16D_LBPME)
                        sd->flags |= SDF_LBPME;
        } else {
                memset(&cmd, 0, sizeof(cmd));
                cmd.cmd.opcode = READ_CAPACITY_10;

                memset(datap, 0, sizeof(datap->data));
                if (scsipi_command(periph, (void *)&cmd.cmd, sizeof(cmd.cmd),
                    (void *)datap, sizeof(datap->data), SCSIPIRETRIES, 20000,
                    NULL, flags | XS_CTL_DATA_IN | XS_CTL_SILENT) == 0) {

                        *blksize = _4btol(datap->data.length);
                        rv = _4btol(datap->data.addr) + 1;
                }
        }

        free(datap, M_TEMP);
        return rv;
}

static int
sd_get_simplifiedparms(struct sd_softc *sd, struct disk_parms *dp, int flags)
{
        struct {
                struct scsi_mode_parameter_header_6 header;
                /* no block descriptor */
                u_int8_t pg_code; /* page code (should be 6) */
                u_int8_t pg_length; /* page length (should be 11) */
                u_int8_t wcd; /* bit0: cache disable */
                u_int8_t lbs[2]; /* logical block size */
                u_int8_t size[5]; /* number of log. blocks */
                u_int8_t pp; /* power/performance */
                u_int8_t flags;
                u_int8_t resvd;
        } scsipi_sense;
        u_int64_t blocks;
        int error, blksize;

        /*
         * sd_read_capacity (ie "read capacity") and mode sense page 6
         * give the same information. Do both for now, and check
         * for consistency.
         * XXX probably differs for removable media
         */
        dp->blksize = SD_DEFAULT_BLKSIZE;
        if ((blocks = sd_read_capacity(sd, &blksize, flags)) == 0)
                return (SDGP_RESULT_OFFLINE);           /* XXX? */

        error = scsipi_mode_sense(sd->sc_periph, SMS_DBD, 6,
            &scsipi_sense.header, sizeof(scsipi_sense),
            flags, SDRETRIES, 6000);

        if (error != 0)
                return (SDGP_RESULT_OFFLINE);           /* XXX? */

        dp->blksize = blksize;
        if (!sd_validate_blksize(NULL, dp->blksize))
                dp->blksize = _2btol(scsipi_sense.lbs);
        if (!sd_validate_blksize(sd->sc_periph, dp->blksize))
                dp->blksize = SD_DEFAULT_BLKSIZE;

        /*
         * Create a pseudo-geometry.
         */
        dp->heads = 64;
        dp->sectors = 32;
        dp->cyls = blocks / (dp->heads * dp->sectors);
        dp->disksize = _5btol(scsipi_sense.size);
        if (dp->disksize <= UINT32_MAX && dp->disksize != blocks) {
                printf("RBC size: mode sense=%llu, get cap=%llu\n",
                       (unsigned long long)dp->disksize,
                       (unsigned long long)blocks);
                dp->disksize = blocks;
        }
        dp->disksize512 = (dp->disksize * dp->blksize) / DEV_BSIZE;

        return (SDGP_RESULT_OK);
}

/*
 * Get the scsi driver to send a full inquiry to the * device and use the
 * results to fill out the disk parameter structure.
 */
static int
sd_get_capacity(struct sd_softc *sd, struct disk_parms *dp, int flags)
{
        u_int64_t blocks;
        int error, blksize;
#if 0
        int i;
        u_int8_t *p;
#endif

        dp->disksize = blocks = sd_read_capacity(sd, &blksize, flags);
        if (blocks == 0) {
                struct scsipi_read_format_capacities cmd;
                struct {
                        struct scsipi_capacity_list_header header;
                        struct scsipi_capacity_descriptor desc;
                } __packed data;

                memset(&cmd, 0, sizeof(cmd));
                memset(&data, 0, sizeof(data));
                cmd.opcode = READ_FORMAT_CAPACITIES;
                _lto2b(sizeof(data), cmd.length);

                error = scsipi_command(sd->sc_periph,
                    (void *)&cmd, sizeof(cmd), (void *)&data, sizeof(data),
                    SDRETRIES, 20000, NULL,
                    flags | XS_CTL_DATA_IN | XS_CTL_SILENT);
                if (error == EFTYPE) {
                        /* Medium Format Corrupted, handle as not formatted */
                        return (SDGP_RESULT_UNFORMATTED);
                }
                if (error || data.header.length == 0)
                        return (SDGP_RESULT_OFFLINE);

#if 0
printf("rfc: length=%d\n", data.header.length);
printf("rfc result:"); for (i = sizeof(struct scsipi_capacity_list_header) + data.header.length, p = (void *)&data; i; i--, p++) printf(" %02x", *p); printf("\n");
#endif
                switch (data.desc.byte5 & SCSIPI_CAP_DESC_CODE_MASK) {
                case SCSIPI_CAP_DESC_CODE_RESERVED:
                case SCSIPI_CAP_DESC_CODE_FORMATTED:
                        break;

                case SCSIPI_CAP_DESC_CODE_UNFORMATTED:
                        return (SDGP_RESULT_UNFORMATTED);

                case SCSIPI_CAP_DESC_CODE_NONE:
                        return (SDGP_RESULT_OFFLINE);
                }

                dp->disksize = blocks = _4btol(data.desc.nblks);
                if (blocks == 0)
                        return (SDGP_RESULT_OFFLINE);           /* XXX? */

                blksize = _3btol(data.desc.blklen);

        } else if (!sd_validate_blksize(NULL, blksize)) {
                struct sd_mode_sense_data scsipi_sense;
                int big, bsize;
                struct scsi_general_block_descriptor *bdesc;

                memset(&scsipi_sense, 0, sizeof(scsipi_sense));
                error = sd_mode_sense(sd, 0, &scsipi_sense,
                    sizeof(scsipi_sense.blk_desc), 0, flags | XS_CTL_SILENT,
                    &big);
                if (error)
                        goto next;
                if (big) {
                        bdesc = (void *)(&scsipi_sense.header.big + 1);
                        bsize = _2btol(scsipi_sense.header.big.blk_desc_len);
                } else {
                        bdesc = (void *)(&scsipi_sense.header.small + 1);
                        bsize = scsipi_sense.header.small.blk_desc_len;
                }

#if 0
printf("page 0 sense:"); for (i = sizeof(scsipi_sense), p = (void *)&scsipi_sense; i; i--, p++) printf(" %02x", *p); printf("\n");
printf("page 0 bsize=%d\n", bsize);
printf("page 0 ok\n");
#endif

                if (bsize >= 8) {
                        blksize = _3btol(bdesc->blklen);
                }
        }
next:
        if (!sd_validate_blksize(sd->sc_periph, blksize))
                blksize = SD_DEFAULT_BLKSIZE;

        dp->blksize = blksize;
        dp->disksize512 = (blocks * dp->blksize) / DEV_BSIZE;

        if ((sd->flags & SDF_LBPME) == 0)
                goto end;
        struct scsipi_inquiry cmd;
        struct scsi_vpd_logical_block_provisioning vpdbuf;
        memset(&cmd, 0, sizeof(cmd));
        cmd.opcode = INQUIRY;
        cmd.length = sizeof(vpdbuf);
        cmd.byte2 |= SINQ_EVPD;
        cmd.pagecode = SINQ_VPD_LOGICAL_PROV;

        sd->flags &= ~SDF_LBPU;
        if (scsipi_command(sd->sc_periph, (void *)&cmd, sizeof(cmd),
                (void *)&vpdbuf, sizeof(vpdbuf),
                SDRETRIES, 100000, NULL,
                flags | XS_CTL_DATA_IN | XS_CTL_IGNORE_ILLEGAL_REQUEST))
                goto end;

        if (vpdbuf.flags & VPD_LBP_LBPU)
                sd->flags |= SDF_LBPU;

end:
        return (0);
}

static int
sd_get_parms_page4(struct sd_softc *sd, struct disk_parms *dp, int flags)
{
        struct sd_mode_sense_data scsipi_sense;
        int error;
        int big, byte2;
        size_t poffset;
        union scsi_disk_pages *pages;

        byte2 = SMS_DBD;
again:
        memset(&scsipi_sense, 0, sizeof(scsipi_sense));
        error = sd_mode_sense(sd, byte2, &scsipi_sense,
            (byte2 ? 0 : sizeof(scsipi_sense.blk_desc)) +
            sizeof(scsipi_sense.pages.rigid_geometry), 4,
            flags | XS_CTL_SILENT, &big);
        if (error) {
                if (byte2 == SMS_DBD) {
                        /* No result; try once more with DBD off */
                        byte2 = 0;
                        goto again;
                }
                return (error);
        }

        if (big) {
                poffset = sizeof scsipi_sense.header.big;
                poffset += _2btol(scsipi_sense.header.big.blk_desc_len);
        } else {
                poffset = sizeof scsipi_sense.header.small;
                poffset += scsipi_sense.header.small.blk_desc_len;
        }

        if (poffset > sizeof(scsipi_sense) - sizeof(pages->rigid_geometry))
                return ERESTART;

        pages = (void *)((u_long)&scsipi_sense + poffset);
#if 0
        {
                size_t i;
                u_int8_t *p;

                printf("page 4 sense:");
                for (i = sizeof(scsipi_sense), p = (void *)&scsipi_sense; i;
                    i--, p++)
                        printf(" %02x", *p);
                printf("\n");
                printf("page 4 pg_code=%d sense=%p/%p\n",
                    pages->rigid_geometry.pg_code, &scsipi_sense, pages);
        }
#endif

        if ((pages->rigid_geometry.pg_code & PGCODE_MASK) != 4)
                return (ERESTART);

        SC_DEBUG(sd->sc_periph, SCSIPI_DB3,
            ("%d cyls, %d heads, %d precomp, %d red_write, %d land_zone\n",
            _3btol(pages->rigid_geometry.ncyl),
            pages->rigid_geometry.nheads,
            _2btol(pages->rigid_geometry.st_cyl_wp),
            _2btol(pages->rigid_geometry.st_cyl_rwc),
            _2btol(pages->rigid_geometry.land_zone)));

        /*
         * KLUDGE!! (for zone recorded disks)
         * give a number of sectors so that sec * trks * cyls
         * is <= disk_size
         * can lead to wasted space! THINK ABOUT THIS !
         */
        dp->heads = pages->rigid_geometry.nheads;
        dp->cyls = _3btol(pages->rigid_geometry.ncyl);
        if (dp->heads == 0 || dp->cyls == 0)
                return (ERESTART);
        dp->sectors = dp->disksize / (dp->heads * dp->cyls);    /* XXX */

        dp->rot_rate = _2btol(pages->rigid_geometry.rpm);
        if (dp->rot_rate == 0)
                dp->rot_rate = 3600;

#if 0
printf("page 4 ok\n");
#endif
        return (0);
}

static int
sd_get_parms_page5(struct sd_softc *sd, struct disk_parms *dp, int flags)
{
        struct sd_mode_sense_data scsipi_sense;
        int error;
        int big, byte2;
        size_t poffset;
        union scsi_disk_pages *pages;

        byte2 = SMS_DBD;
again:
        memset(&scsipi_sense, 0, sizeof(scsipi_sense));
        error = sd_mode_sense(sd, 0, &scsipi_sense,
            (byte2 ? 0 : sizeof(scsipi_sense.blk_desc)) +
            sizeof(scsipi_sense.pages.flex_geometry), 5,
            flags | XS_CTL_SILENT, &big);
        if (error) {
                if (byte2 == SMS_DBD) {
                        /* No result; try once more with DBD off */
                        byte2 = 0;
                        goto again;
                }
                return (error);
        }

        if (big) {
                poffset = sizeof scsipi_sense.header.big;
                poffset += _2btol(scsipi_sense.header.big.blk_desc_len);
        } else {
                poffset = sizeof scsipi_sense.header.small;
                poffset += scsipi_sense.header.small.blk_desc_len;
        }

        if (poffset > sizeof(scsipi_sense) - sizeof(pages->flex_geometry))
                return ERESTART;

        pages = (void *)((u_long)&scsipi_sense + poffset);
#if 0
        {
                size_t i;
                u_int8_t *p;

                printf("page 5 sense:");
                for (i = sizeof(scsipi_sense), p = (void *)&scsipi_sense; i;
                    i--, p++)
                        printf(" %02x", *p);
                printf("\n");
                printf("page 5 pg_code=%d sense=%p/%p\n",
                    pages->flex_geometry.pg_code, &scsipi_sense, pages);
        }
#endif

        if ((pages->flex_geometry.pg_code & PGCODE_MASK) != 5)
                return (ERESTART);

        SC_DEBUG(sd->sc_periph, SCSIPI_DB3,
            ("%d cyls, %d heads, %d sec, %d bytes/sec\n",
            _3btol(pages->flex_geometry.ncyl),
            pages->flex_geometry.nheads,
            pages->flex_geometry.ph_sec_tr,
            _2btol(pages->flex_geometry.bytes_s)));

        dp->heads = pages->flex_geometry.nheads;
        dp->cyls = _2btol(pages->flex_geometry.ncyl);
        dp->sectors = pages->flex_geometry.ph_sec_tr;
        if (dp->heads == 0 || dp->cyls == 0 || dp->sectors == 0)
                return (ERESTART);

        dp->rot_rate = _2btol(pages->rigid_geometry.rpm);
        if (dp->rot_rate == 0)
                dp->rot_rate = 3600;

#if 0
printf("page 5 ok\n");
#endif
        return (0);
}

static int
sd_get_parms(struct sd_softc *sd, struct disk_parms *dp, int flags)
{
        struct dk_softc *dksc = &sd->sc_dksc;
        int error;

        /*
         * If offline, the SDEV_MEDIA_LOADED flag will be
         * cleared by the caller if necessary.
         */
        if (sd->type == T_SIMPLE_DIRECT) {
                error = sd_get_simplifiedparms(sd, dp, flags);
                if (!error)
                        goto setprops;
                return (error);
        }

        error = sd_get_capacity(sd, dp, flags);
        if (error)
                return (error);

        if (sd->type == T_OPTICAL)
                goto page0;

        if (sd->sc_periph->periph_flags & PERIPH_REMOVABLE) {
                if (!sd_get_parms_page5(sd, dp, flags) ||
                    !sd_get_parms_page4(sd, dp, flags))
                        goto setprops;
        } else {
                if (!sd_get_parms_page4(sd, dp, flags) ||
                    !sd_get_parms_page5(sd, dp, flags))
                        goto setprops;
        }

page0:
        printf("%s: fabricating a geometry\n", dksc->sc_xname);
        /* Try calling driver's method for figuring out geometry. */
        if (!sd->sc_periph->periph_channel->chan_adapter->adapt_getgeom ||
            !(*sd->sc_periph->periph_channel->chan_adapter->adapt_getgeom)
                (sd->sc_periph, dp, dp->disksize)) {
                /*
                 * Use adaptec standard fictitious geometry
                 * this depends on which controller (e.g. 1542C is
                 * different. but we have to put SOMETHING here..)
                 */
                dp->heads = 64;
                dp->sectors = 32;
                dp->cyls = dp->disksize / (64 * 32);
        }
        dp->rot_rate = 3600;

setprops:
        sd_set_geometry(sd);

        return (SDGP_RESULT_OK);
}

static int
sd_flush(struct sd_softc *sd, int flags)
{
        struct scsipi_periph *periph = sd->sc_periph;
        struct scsi_synchronize_cache_10 cmd;

        /*
         * If the device is SCSI-2, issue a SYNCHRONIZE CACHE.
         * We issue with address 0 length 0, which should be
         * interpreted by the device as "all remaining blocks
         * starting at address 0".  We ignore ILLEGAL REQUEST
         * in the event that the command is not supported by
         * the device, and poll for completion so that we know
         * that the cache has actually been flushed.
         *
         * Unless, that is, the device can't handle the SYNCHRONIZE CACHE
         * command, as indicated by our quirks flags.
         *
         * XXX What about older devices?
         */
        if (periph->periph_version < 2 ||
            (periph->periph_quirks & PQUIRK_NOSYNCCACHE))
                return (0);

        sd->flags |= SDF_FLUSHING;
        memset(&cmd, 0, sizeof(cmd));
        cmd.opcode = SCSI_SYNCHRONIZE_CACHE_10;

        return (scsipi_command(periph, (void *)&cmd, sizeof(cmd), 0, 0,
            SDRETRIES, 100000, NULL, flags | XS_CTL_IGNORE_ILLEGAL_REQUEST));
}

static int
sd_getcache(struct sd_softc *sd, int *bitsp)
{
        struct scsipi_periph *periph = sd->sc_periph;
        struct sd_mode_sense_data scsipi_sense;
        int error, bits = 0;
        int big;
        union scsi_disk_pages *pages;
        uint8_t dev_spec;

        /* only SCSI-2 and later supported */
        if (periph->periph_version < 2)
                return (EOPNOTSUPP);

        memset(&scsipi_sense, 0, sizeof(scsipi_sense));
        error = sd_mode_sense(sd, SMS_DBD, &scsipi_sense,
            sizeof(scsipi_sense.pages.caching_params), 8, XS_CTL_SILENT, &big);
        if (error)
                return (error);

        if (big) {
                pages = (void *)(&scsipi_sense.header.big + 1);
                dev_spec = scsipi_sense.header.big.dev_spec;
        } else {
                pages = (void *)(&scsipi_sense.header.small + 1);
                dev_spec = scsipi_sense.header.small.dev_spec;
        }

        if ((pages->caching_params.flags & CACHING_RCD) == 0)
                bits |= DKCACHE_READ;
        if (pages->caching_params.flags & CACHING_WCE)
                bits |= DKCACHE_WRITE;
        if (pages->caching_params.pg_code & PGCODE_PS)
                bits |= DKCACHE_SAVE;

        /*
         * Support for FUA/DPO, defined starting with SCSI-2. Use only
         * if device claims to support it, according to the MODE SENSE.
         */
        if (!(periph->periph_quirks & PQUIRK_NOFUA) &&
            ISSET(dev_spec, SMH_DSP_DPOFUA))
                bits |= DKCACHE_FUA | DKCACHE_DPO;

        memset(&scsipi_sense, 0, sizeof(scsipi_sense));
        error = sd_mode_sense(sd, SMS_DBD, &scsipi_sense,
            sizeof(scsipi_sense.pages.caching_params),
            SMS_PCTRL_CHANGEABLE|8, XS_CTL_SILENT, &big);
        if (error == 0) {
                if (big)
                        pages = (void *)(&scsipi_sense.header.big + 1);
                else
                        pages = (void *)(&scsipi_sense.header.small + 1);

                if (pages->caching_params.flags & CACHING_RCD)
                        bits |= DKCACHE_RCHANGE;
                if (pages->caching_params.flags & CACHING_WCE)
                        bits |= DKCACHE_WCHANGE;
        }

        *bitsp = bits;

        return (0);
}

static int
sd_setcache(struct sd_softc *sd, int bits)
{
        struct scsipi_periph *periph = sd->sc_periph;
        struct sd_mode_sense_data scsipi_sense;
        int error;
        uint8_t oflags, byte2 = 0;
        int big;
        union scsi_disk_pages *pages;

        if (periph->periph_version < 2)
                return (EOPNOTSUPP);

        memset(&scsipi_sense, 0, sizeof(scsipi_sense));
        error = sd_mode_sense(sd, SMS_DBD, &scsipi_sense,
            sizeof(scsipi_sense.pages.caching_params), 8, 0, &big);
        if (error)
                return (error);

        if (big)
                pages = (void *)(&scsipi_sense.header.big + 1);
        else
                pages = (void *)(&scsipi_sense.header.small + 1);

        oflags = pages->caching_params.flags;

        if (bits & DKCACHE_READ)
                pages->caching_params.flags &= ~CACHING_RCD;
        else
                pages->caching_params.flags |= CACHING_RCD;

        if (bits & DKCACHE_WRITE)
                pages->caching_params.flags |= CACHING_WCE;
        else
                pages->caching_params.flags &= ~CACHING_WCE;

        if (oflags == pages->caching_params.flags)
                return (0);

        pages->caching_params.pg_code &= PGCODE_MASK;

        if (bits & DKCACHE_SAVE)
                byte2 |= SMS_SP;

        return (sd_mode_select(sd, byte2|SMS_PF, &scsipi_sense,
            sizeof(struct scsi_mode_page_header) +
            pages->caching_params.pg_length, 0, big));
}

static void
sd_set_geometry(struct sd_softc *sd)
{
        struct dk_softc *dksc = &sd->sc_dksc;
        struct disk_geom *dg = &dksc->sc_dkdev.dk_geom;

        memset(dg, 0, sizeof(*dg));

        dg->dg_secperunit = sd->params.disksize;
        dg->dg_secsize = sd->params.blksize;
        dg->dg_nsectors = sd->params.sectors;
        dg->dg_ntracks = sd->params.heads;
        dg->dg_ncylinders = sd->params.cyls;
        dg->dg_physsecsize = dg->dg_secsize << sd->params.lbppbe;
        dg->dg_alignedsec = sd->params.lalba;

        disk_set_info(dksc->sc_dev, &dksc->sc_dkdev, sd->typename);
}

static int
sddiscard(dev_t dev, off_t pos, off_t len)
{
        struct sd_softc *sd;
        int unit;

        unit = SDUNIT(dev);
        sd = device_lookup_private(&sd_cd, unit);

        return dk_discard(&sd->sc_dksc, dev, pos, len);
}