/*      $NetBSD: wd.c,v 1.476 2026/07/04 00:13:39 jakllsch Exp $ */

/*
 * Copyright (c) 1998, 2001 Manuel Bouyer.  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.
 *
 * 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.
 */

/*-
 * 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 and by Onno van der Linden.
 *
 * 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.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: wd.c,v 1.476 2026/07/04 00:13:39 jakllsch Exp $");

#include "opt_ata.h"
#include "opt_wd.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/buf.h>
#include <sys/bufq.h>
#include <sys/uio.h>
#include <sys/device.h>
#include <sys/disklabel.h>
#include <sys/disk.h>
#include <sys/dkbad.h>
#include <sys/syslog.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <sys/vnode.h>
#include <sys/rndsource.h>

#include <sys/intr.h>
#include <sys/bus.h>

#include <dev/ata/atareg.h>
#include <dev/ata/atavar.h>
#include <dev/ata/wdvar.h>
#include <dev/ic/wdcreg.h>
#include <sys/ataio.h>
#include "locators.h"

#include <prop/proplib.h>

#define WDIORETRIES_SINGLE 4    /* number of retries for single-sector */
#define WDIORETRIES     5       /* number of retries before giving up */
#define RECOVERYTIME hz/2       /* time to wait before retrying a cmd */

#define WDUNIT(dev)             DISKUNIT(dev)
#define WDPART(dev)             DISKPART(dev)
#define WDMINOR(unit, part)     DISKMINOR(unit, part)
#define MAKEWDDEV(maj, unit, part)      MAKEDISKDEV(maj, unit, part)

#define WDLABELDEV(dev) (MAKEWDDEV(major(dev), WDUNIT(dev), RAW_PART))

#define DEBUG_FUNCS  0x08
#define DEBUG_PROBE  0x10
#define DEBUG_DETACH 0x20
#define DEBUG_XFERS  0x40
#ifdef ATADEBUG
#ifndef ATADEBUG_WD_MASK
#define ATADEBUG_WD_MASK 0x0
#endif
int wdcdebug_wd_mask = ATADEBUG_WD_MASK;
#define ATADEBUG_PRINT(args, level) \
        if (wdcdebug_wd_mask & (level)) \
                printf args
#else
#define ATADEBUG_PRINT(args, level)
#endif

static int      wdprobe(device_t, cfdata_t, void *);
static void     wdattach(device_t, device_t, void *);
static int      wddetach(device_t, int);
static void     wdperror(const struct wd_softc *, struct ata_xfer *);

static void     wdminphys(struct buf *);

static int      wd_firstopen(device_t, dev_t, int, int);
static int      wd_lastclose(device_t);
static bool     wd_suspend(device_t, const pmf_qual_t *);
static int      wd_standby(struct wd_softc *, int);

CFATTACH_DECL3_NEW(wd, sizeof(struct wd_softc),
    wdprobe, wdattach, wddetach, NULL, NULL, NULL, DVF_DETACH_SHUTDOWN);

extern struct cfdriver wd_cd;

static dev_type_open(wdopen);
static dev_type_close(wdclose);
static dev_type_read(wdread);
static dev_type_write(wdwrite);
static dev_type_ioctl(wdioctl);
static dev_type_strategy(wdstrategy);
static dev_type_dump(wddump);
static dev_type_size(wdsize);
static dev_type_discard(wddiscard);

const struct bdevsw wd_bdevsw = {
        .d_open = wdopen,
        .d_close = wdclose,
        .d_strategy = wdstrategy,
        .d_ioctl = wdioctl,
        .d_dump = wddump,
        .d_psize = wdsize,
        .d_discard = wddiscard,
        .d_cfdriver = &wd_cd,
        .d_devtounit = disklabel_dev_unit,
        .d_flag = D_DISK
};

const struct cdevsw wd_cdevsw = {
        .d_open = wdopen,
        .d_close = wdclose,
        .d_read = wdread,
        .d_write = wdwrite,
        .d_ioctl = wdioctl,
        .d_stop = nostop,
        .d_tty = notty,
        .d_poll = nopoll,
        .d_mmap = nommap,
        .d_kqfilter = nokqfilter,
        .d_discard = wddiscard,
        .d_cfdriver = &wd_cd,
        .d_devtounit = disklabel_dev_unit,
        .d_flag = D_DISK
};

/* #define WD_DUMP_NOT_TRUSTED if you just want to watch */
static int wddoingadump = 0;
static int wddumprecalibrated = 0;

/*
 * Glue necessary to hook WDCIOCCOMMAND into physio
 */

struct wd_ioctl {
        LIST_ENTRY(wd_ioctl) wi_list;
        struct buf wi_bp;
        struct uio wi_uio;
        struct iovec wi_iov;
        atareq_t wi_atareq;
        struct wd_softc *wi_softc;
};

static struct   wd_ioctl *wi_find(struct buf *);
static void     wi_free(struct wd_ioctl *);
static struct   wd_ioctl *wi_get(struct wd_softc *);
static void     wdioctlstrategy(struct buf *);

static void     wdrestart(void *);
static void     wdstart1(struct wd_softc *, struct buf *, struct ata_xfer *);
static int      wd_diskstart(device_t, struct buf *);
static int      wd_dumpblocks(device_t, void *, daddr_t, int);
static void     wd_iosize(device_t, int *);
static int      wd_discard(device_t, off_t, off_t);
static void     wdbioretry(void *);
static void     wdbiorequeue(void *);
static void     wddone(device_t, struct ata_xfer *);
static int      wd_get_params(struct wd_softc *, struct ataparams *);
static void     wd_set_geometry(struct wd_softc *);
static int      wd_flushcache(struct wd_softc *, int);
static int      wd_trim(struct wd_softc *, daddr_t, long);
static bool     wd_shutdown(device_t, int);

static int wd_getcache(struct wd_softc *, int *);
static int wd_setcache(struct wd_softc *, int);

static void wd_sysctl_attach(struct wd_softc *);
static void wd_sysctl_detach(struct wd_softc *);

static const struct dkdriver wddkdriver = {
        .d_open = wdopen,
        .d_close = wdclose,
        .d_strategy = wdstrategy,
        .d_minphys = wdminphys,
        .d_diskstart = wd_diskstart,
        .d_dumpblocks = wd_dumpblocks,
        .d_iosize = wd_iosize,
        .d_firstopen = wd_firstopen,
        .d_lastclose = wd_lastclose,
        .d_discard = wd_discard
};

#define WD_QUIRK_SPLIT_MOD15_WRITE      0x0001  /* must split certain writes */

#define WD_QUIRK_FMT "\20\1SPLIT_MOD15_WRITE"

/*
 * Quirk table for IDE drives.  Put more-specific matches first, since
 * a simple globing routine is used for matching.
 */
static const struct wd_quirk {
        const char *wdq_match;          /* inquiry pattern to match */
        int wdq_quirks;                 /* drive quirks */
} wd_quirk_table[] = {
        /*
         * Some Seagate S-ATA drives have a PHY which can get confused
         * with the way data is packetized by some S-ATA controllers.
         *
         * The work-around is to split in two any write transfer whose
         * sector count % 15 == 1 (assuming 512 byte sectors).
         *
         * XXX This is an incomplete list.  There are at least a couple
         * XXX more model numbers.  If you have trouble with such transfers
         * XXX (8K is the most common) on Seagate S-ATA drives, please
         * XXX notify thorpej@NetBSD.org.
         *
         * The ST360015AS has not yet been confirmed to have this
         * issue, however, it is the only other drive in the
         * Seagate Barracuda Serial ATA V family.
         *
         */
        { "ST3120023AS", WD_QUIRK_SPLIT_MOD15_WRITE },
        { "ST380023AS", WD_QUIRK_SPLIT_MOD15_WRITE },
        { "ST360015AS", WD_QUIRK_SPLIT_MOD15_WRITE },
        { NULL,
          0 }
};

static const struct wd_quirk *
wd_lookup_quirks(const char *name)
{
        const struct wd_quirk *wdq;
        const char *estr;

        for (wdq = wd_quirk_table; wdq->wdq_match != NULL; wdq++) {
                /*
                 * We only want exact matches (which include matches
                 * against globbing characters).
                 */
                if (pmatch(name, wdq->wdq_match, &estr) == 2)
                        return (wdq);
        }
        return (NULL);
}

static int
wdprobe(device_t parent, cfdata_t match, void *aux)
{
        struct ata_device *adev = aux;

        if (adev == NULL)
                return 0;
        if (adev->adev_bustype->bustype_type != SCSIPI_BUSTYPE_ATA)
                return 0;

        if (match->cf_loc[ATA_HLCF_DRIVE] != ATA_HLCF_DRIVE_DEFAULT &&
            match->cf_loc[ATA_HLCF_DRIVE] != adev->adev_drv_data->drive)
                return 0;
        return 1;
}

static void
wdattach(device_t parent, device_t self, void *aux)
{
        struct wd_softc *wd = device_private(self);
        struct dk_softc *dksc = &wd->sc_dksc;
        struct ata_device *adev= aux;
        int i, blank;
        uint32_t firstaligned = 0, alignment = 1;
        char tbuf[41],pbuf[9], c, *p, *q;
        const struct wd_quirk *wdq;
        int dtype = DKTYPE_UNKNOWN;

        dksc->sc_dev = self;

        ATADEBUG_PRINT(("wdattach\n"), DEBUG_FUNCS | DEBUG_PROBE);
        mutex_init(&wd->sc_lock, MUTEX_DEFAULT, IPL_BIO);
#ifdef WD_SOFTBADSECT
        SLIST_INIT(&wd->sc_bslist);
        cv_init(&wd->sc_bslist_cv, "wdbadsect");
#endif
        wd->atabus = adev->adev_bustype;
        wd->inflight = 0;
        wd->drvp = adev->adev_drv_data;

        wd->drvp->drv_openings = 1;
        wd->drvp->drv_done = wddone;
        wd->drvp->drv_softc = dksc->sc_dev; /* done in atabusconfig_thread()
                                             but too late */

        SLIST_INIT(&wd->sc_retry_list);
        SLIST_INIT(&wd->sc_requeue_list);
        callout_init(&wd->sc_retry_callout, 0);         /* XXX MPSAFE */
        callout_init(&wd->sc_requeue_callout, 0);       /* XXX MPSAFE */
        callout_init(&wd->sc_restart_diskqueue, 0);     /* XXX MPSAFE */

        aprint_naive("\n");
        aprint_normal("\n");

        /* read our drive info */
        if (wd_get_params(wd, &wd->sc_params) != 0) {
                aprint_error_dev(self, "IDENTIFY failed\n");
                goto out;
        }

        for (blank = 0, p = wd->sc_params.atap_model, q = tbuf, i = 0;
            i < sizeof(wd->sc_params.atap_model); i++) {
                c = *p++;
                if (c == '\0')
                        break;
                if (c != ' ') {
                        if (blank) {
                                *q++ = ' ';
                                blank = 0;
                        }
                        *q++ = c;
                } else
                        blank = 1;
        }
        *q++ = '\0';

        wd->sc_typename = kmem_asprintf("%s", tbuf);
        aprint_normal_dev(self, "<%s>\n", wd->sc_typename);

        wdq = wd_lookup_quirks(tbuf);
        if (wdq != NULL)
                wd->sc_quirks = wdq->wdq_quirks;

        if (wd->sc_quirks != 0) {
                char sbuf[sizeof(WD_QUIRK_FMT) + 64];
                snprintb(sbuf, sizeof(sbuf), WD_QUIRK_FMT, wd->sc_quirks);
                aprint_normal_dev(self, "quirks %s\n", sbuf);

                if (wd->sc_quirks & WD_QUIRK_SPLIT_MOD15_WRITE) {
                        aprint_error_dev(self, "drive corrupts write transfers with certain controllers, consider replacing\n");
                }
        }

        if ((wd->sc_params.atap_multi & 0xff) > 1) {
                wd->drvp->multi = wd->sc_params.atap_multi & 0xff;
        } else {
                wd->drvp->multi = 1;
        }

        aprint_verbose_dev(self, "drive supports %d-sector PIO transfers,",
            wd->drvp->multi);

        /* 48-bit LBA addressing */
        if ((wd->sc_params.atap_cmd2_en & ATA_CMD2_LBA48) != 0)
                wd->sc_flags |= WDF_LBA48;

        /* Prior to ATA-4, LBA was optional. */
        if ((wd->sc_params.atap_capabilities1 & WDC_CAP_LBA) != 0)
                wd->sc_flags |= WDF_LBA;
#if 0
        /* ATA-4 requires LBA. */
        if (wd->sc_params.atap_ataversion != 0xffff &&
            wd->sc_params.atap_ataversion >= WDC_VER_ATA4)
                wd->sc_flags |= WDF_LBA;
#endif

        if ((wd->sc_flags & WDF_LBA48) != 0) {
                aprint_verbose(" LBA48 addressing\n");
                wd->sc_capacity =
                    ((uint64_t) wd->sc_params.atap_max_lba[3] << 48) |
                    ((uint64_t) wd->sc_params.atap_max_lba[2] << 32) |
                    ((uint64_t) wd->sc_params.atap_max_lba[1] << 16) |
                    ((uint64_t) wd->sc_params.atap_max_lba[0] <<  0);
                wd->sc_capacity28 =
                    (wd->sc_params.atap_capacity[1] << 16) |
                    wd->sc_params.atap_capacity[0];
                /*
                 * Force LBA48 addressing for invalid numbers.
                 */
                if (wd->sc_capacity28 > 0xfffffff)
                        wd->sc_capacity28 = 0xfffffff;
        } else if ((wd->sc_flags & WDF_LBA) != 0) {
                aprint_verbose(" LBA addressing\n");
                wd->sc_capacity28 =
                    (wd->sc_params.atap_capacity[1] << 16) |
                    wd->sc_params.atap_capacity[0];
                /*
                 * Limit capacity to LBA28 numbers to avoid overflow.
                 */
                if (wd->sc_capacity28 > 0xfffffff)
                        wd->sc_capacity28 = 0xfffffff;
                wd->sc_capacity = wd->sc_capacity28;
        } else {
                aprint_verbose(" chs addressing\n");
                wd->sc_capacity =
                    wd->sc_params.atap_cylinders *
                    wd->sc_params.atap_heads *
                    wd->sc_params.atap_sectors;
                /*
                 * LBA28 size is ignored for CHS addressing. Use a reasonable
                 * value for debugging. The CHS values may be artificial and
                 * are mostly ignored.
                 */
                if (wd->sc_capacity < 0xfffffff)
                        wd->sc_capacity28 = wd->sc_capacity;
                else
                        wd->sc_capacity28 = 0xfffffff;
        }
        if ((wd->sc_params.atap_secsz & ATA_SECSZ_VALID_MASK) == ATA_SECSZ_VALID
            && ((wd->sc_params.atap_secsz & ATA_SECSZ_LLS) != 0)) {
                wd->sc_blksize = 2ULL *
                    ((uint32_t)((wd->sc_params.atap_lls_secsz[1] << 16) |
                    wd->sc_params.atap_lls_secsz[0]));
        } else {
                wd->sc_blksize = 512;
        }
        if ((wd->sc_params.atap_secsz & ATA_SECSZ_VALID_MASK) == ATA_SECSZ_VALID
            && ((wd->sc_params.atap_secsz & ATA_SECSZ_LPS) != 0)) {
                alignment = 1 <<
                    (wd->sc_params.atap_secsz & ATA_SECSZ_LPS_SZMSK);
                if ((wd->sc_params.atap_logical_align & ATA_LA_VALID_MASK) ==
                    ATA_LA_VALID) {
                        firstaligned =
                            wd->sc_params.atap_logical_align & ATA_LA_MASK;
                }
        }
        wd->sc_capacity512 = (wd->sc_capacity * wd->sc_blksize) / DEV_BSIZE;
        format_bytes(pbuf, sizeof(pbuf), wd->sc_capacity * wd->sc_blksize);
        aprint_normal_dev(self, "%s, %d cyl, %d head, %d sec, "
            "%d bytes/sect x %llu sectors",
            pbuf,
            (wd->sc_flags & WDF_LBA) ? (int)(wd->sc_capacity /
                (wd->sc_params.atap_heads * wd->sc_params.atap_sectors)) :
                wd->sc_params.atap_cylinders,
            wd->sc_params.atap_heads, wd->sc_params.atap_sectors,
            wd->sc_blksize, (unsigned long long)wd->sc_capacity);
        if (alignment != 1) {
                aprint_normal(" (%d bytes/physsect",
                    alignment * wd->sc_blksize);
                if (firstaligned != 0) {
                        aprint_normal("; first aligned sector: %jd",
                            (intmax_t)firstaligned);
                }
                aprint_normal(")");
        }
        aprint_normal("\n");

        ATADEBUG_PRINT(("%s: atap_dmatiming_mimi=%d, atap_dmatiming_recom=%d\n",
            device_xname(self), wd->sc_params.atap_dmatiming_mimi,
            wd->sc_params.atap_dmatiming_recom), DEBUG_PROBE);

        if (wd->sc_blksize <= 0 || !powerof2(wd->sc_blksize) ||
            wd->sc_blksize < DEV_BSIZE || wd->sc_blksize > MAXPHYS) {
                aprint_normal_dev(self, "WARNING: block size %u "
                    "might not actually work\n", wd->sc_blksize);
        }

        if (strcmp(wd->sc_params.atap_model, "ST506") == 0)
                dtype = DKTYPE_ST506;
        else
                dtype = DKTYPE_ESDI;

out:
        /*
         * Initialize and attach the disk structure.
         */
        dk_init(dksc, self, dtype);
        disk_init(&dksc->sc_dkdev, dksc->sc_xname, &wddkdriver);

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

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

        /* reference to label structure, used by ata code */
        wd->drvp->lp = dksc->sc_dkdev.dk_label;

        /* Discover wedges on this disk. */
        dkwedge_discover(&dksc->sc_dkdev);

        if (!pmf_device_register1(self, wd_suspend, NULL, wd_shutdown))
                aprint_error_dev(self, "couldn't establish power handler\n");

        wd_sysctl_attach(wd);
}

static bool
wd_suspend(device_t dv, const pmf_qual_t *qual)
{
        struct wd_softc *sc = device_private(dv);

        /* the adapter needs to be enabled */
        if (sc->atabus->ata_addref(sc->drvp))
                return true; /* no need to complain */

        wd_flushcache(sc, AT_WAIT);
        wd_standby(sc, AT_WAIT);

        sc->atabus->ata_delref(sc->drvp);
        return true;
}

static int
wddetach(device_t self, int flags)
{
        struct wd_softc *wd = device_private(self);
        struct dk_softc *dksc = &wd->sc_dksc;
        int bmaj, cmaj, i, mn, rc;

        if ((rc = disk_begindetach(&dksc->sc_dkdev, wd_lastclose, self, flags)) != 0)
                return rc;

        /* locate the major number */
        bmaj = bdevsw_lookup_major(&wd_bdevsw);
        cmaj = cdevsw_lookup_major(&wd_cdevsw);

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

        dk_drain(dksc);

        /* Kill off any pending commands. */
        mutex_enter(&wd->sc_lock);
        wd->atabus->ata_killpending(wd->drvp);

        callout_halt(&wd->sc_retry_callout, &wd->sc_lock);
        callout_destroy(&wd->sc_retry_callout);
        callout_halt(&wd->sc_requeue_callout, &wd->sc_lock);
        callout_destroy(&wd->sc_requeue_callout);
        callout_halt(&wd->sc_restart_diskqueue, &wd->sc_lock);
        callout_destroy(&wd->sc_restart_diskqueue);

        mutex_exit(&wd->sc_lock);

        bufq_free(dksc->sc_bufq);

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

        if (flags & DETACH_POWEROFF)
                wd_standby(wd, AT_POLL);

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

        dk_detach(dksc);

#ifdef WD_SOFTBADSECT
        /* Clean out the bad sector list */
        while (!SLIST_EMPTY(&wd->sc_bslist)) {
                struct disk_badsectors *dbs = SLIST_FIRST(&wd->sc_bslist);
                SLIST_REMOVE_HEAD(&wd->sc_bslist, dbs_next);
                kmem_free(dbs, sizeof(*dbs));
        }
        wd->sc_bscount = 0;
#endif
        if (wd->sc_typename != NULL) {
                kmem_free(wd->sc_typename, strlen(wd->sc_typename) + 1);
                wd->sc_typename = NULL;
        }

        pmf_device_deregister(self);

        wd_sysctl_detach(wd);

#ifdef WD_SOFTBADSECT
        KASSERT(SLIST_EMPTY(&wd->sc_bslist));
        cv_destroy(&wd->sc_bslist_cv);
#endif

        mutex_destroy(&wd->sc_lock);

        wd->drvp->drive_type = ATA_DRIVET_NONE; /* no drive any more here */
        wd->drvp->drive_flags = 0;

        return (0);
}

/*
 * Read/write routine for a buffer.  Validates the arguments and schedules the
 * transfer.  Does not wait for the transfer to complete.
 */
static void
wdstrategy(struct buf *bp)
{
        struct wd_softc *wd =
            device_lookup_private(&wd_cd, WDUNIT(bp->b_dev));
        struct dk_softc *dksc = &wd->sc_dksc;

        ATADEBUG_PRINT(("wdstrategy (%s)\n", dksc->sc_xname),
            DEBUG_XFERS);

        /* If device invalidated (e.g. media change, door open,
         * device detachment), then error.
         */
        if ((wd->sc_flags & WDF_LOADED) == 0 ||
            !device_is_enabled(dksc->sc_dev))
                goto err;

#ifdef WD_SOFTBADSECT
        /*
         * If the transfer about to be attempted contains only a block that
         * is known to be bad then return an error for the transfer without
         * even attempting to start a transfer up under the premis that we
         * will just end up doing more retries for a transfer that will end
         * up failing again.
         */
        if (__predict_false(!SLIST_EMPTY(&wd->sc_bslist))) {
                struct disklabel *lp = dksc->sc_dkdev.dk_label;
                struct disk_badsectors *dbs;
                daddr_t blkno, maxblk;

                /* convert the block number to absolute */
                if (lp->d_secsize >= DEV_BSIZE)
                        blkno = bp->b_blkno / (lp->d_secsize / DEV_BSIZE);
                else
                        blkno = bp->b_blkno * (DEV_BSIZE / lp->d_secsize);
                if (WDPART(bp->b_dev) != RAW_PART)
                        blkno += lp->d_partitions[WDPART(bp->b_dev)].p_offset;
                maxblk = blkno + (bp->b_bcount / wd->sc_blksize) - 1;

                mutex_enter(&wd->sc_lock);
                SLIST_FOREACH(dbs, &wd->sc_bslist, dbs_next)
                        if ((dbs->dbs_min <= bp->b_rawblkno &&
                             bp->b_rawblkno <= dbs->dbs_max) ||
                            (dbs->dbs_min <= maxblk && maxblk <= dbs->dbs_max)){
                                mutex_exit(&wd->sc_lock);
                                goto err;
                        }
                mutex_exit(&wd->sc_lock);
        }
#endif

        dk_strategy(dksc, bp);
        return;

err:
        bp->b_error = EIO;
        bp->b_resid = bp->b_bcount;
        biodone(bp);
}

static void
wdstart1(struct wd_softc *wd, struct buf *bp, struct ata_xfer *xfer)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        const uint32_t secsize = dksc->sc_dkdev.dk_geom.dg_secsize;

        KASSERT(bp == xfer->c_bio.bp || xfer->c_bio.bp == NULL);
        KASSERT((xfer->c_flags & (C_WAITACT|C_FREE)) == 0);
        KASSERT(mutex_owned(&wd->sc_lock));

        /* Reset state, so that retries don't use stale info */
        if (__predict_false(xfer->c_retries > 0)) {
                xfer->c_flags = 0;
                memset(&xfer->c_bio, 0, sizeof(xfer->c_bio));
        }

        xfer->c_bio.blkno = bp->b_rawblkno;
        xfer->c_bio.bcount = bp->b_bcount;
        xfer->c_bio.databuf = bp->b_data;
        xfer->c_bio.blkdone = 0;
        xfer->c_bio.bp = bp;

        /* Adjust blkno and bcount if xfer has been already partially done */
        if (__predict_false(xfer->c_skip > 0)) {
                KASSERT(xfer->c_skip < xfer->c_bio.bcount);
                KASSERT((xfer->c_skip % secsize) == 0);
                xfer->c_bio.bcount -= xfer->c_skip;
                xfer->c_bio.blkno += xfer->c_skip / secsize;
        }

#ifdef WD_CHAOS_MONKEY
        /*
         * Override blkno to be over device capacity to trigger error,
         * but only if it's read, to avoid trashing disk contents should
         * the command be clipped, or otherwise misinterpreted, by the
         * driver or controller.
         */
        if (BUF_ISREAD(bp) && xfer->c_retries == 0 && wd->drv_chaos_freq > 0 &&
            (++wd->drv_chaos_cnt % wd->drv_chaos_freq) == 0) {
                device_printf(dksc->sc_dev, "%s: chaos xfer %"PRIxPTR"\n",
                    __func__, (intptr_t)xfer & PAGE_MASK);
                xfer->c_bio.blkno = 7777777 + wd->sc_capacity;
                xfer->c_flags |= C_CHAOS;
        }
#endif

        /*
         * If we're retrying, retry in single-sector mode. This will give us
         * the sector number of the problem, and will eventually allow the
         * transfer to succeed. If FUA is requested, we can't actually
         * do this, as ATA_SINGLE is usually executed as PIO transfer by drivers
         * which support it, and that isn't compatible with NCQ/FUA.
         */
        if (xfer->c_retries >= WDIORETRIES_SINGLE &&
            (bp->b_flags & B_MEDIA_FUA) == 0)
                xfer->c_bio.flags = ATA_SINGLE;
        else
                xfer->c_bio.flags = 0;

        /*
         * request LBA48 transfers when supported by the controller
         * and needed by transfer offset or size.
         */
        if (wd->sc_flags & WDF_LBA48 &&
            (((xfer->c_bio.blkno + xfer->c_bio.bcount / secsize) >
            wd->sc_capacity28) ||
            ((xfer->c_bio.bcount / secsize) > 128)))
                xfer->c_bio.flags |= ATA_LBA48;

        /*
         * If NCQ was negotiated, always use it for the first several attempts.
         * Since device cancels all outstanding requests on error, downgrade
         * to non-NCQ on retry, so that the retried transfer would not cause
         * cascade failure for the other transfers if it fails again.
         * If FUA was requested, we can't downgrade, as that would violate
         * the semantics - FUA would not be honored. In that case, continue
         * retrying with NCQ.
         */
        if (WD_USE_NCQ(wd) && (xfer->c_retries < WDIORETRIES_SINGLE ||
            (bp->b_flags & B_MEDIA_FUA) != 0)) {
                xfer->c_bio.flags |= ATA_LBA48;
                xfer->c_flags |= C_NCQ;

                if (WD_USE_NCQ_PRIO(wd) &&
                    BIO_GETPRIO(bp) == BPRIO_TIMECRITICAL)
                        xfer->c_bio.flags |= ATA_PRIO_HIGH;
        }

        if (wd->sc_flags & WDF_LBA)
                xfer->c_bio.flags |= ATA_LBA;
        if (bp->b_flags & B_READ) {
                xfer->c_bio.flags |= ATA_READ;
        } else {
                /* it's a write */
                wd->sc_flags |= WDF_DIRTY;
        }
        if (bp->b_flags & B_MEDIA_FUA) {
                /* If not using NCQ, the command WRITE DMA FUA EXT is LBA48 */
                KASSERT((wd->sc_flags & WDF_LBA48) != 0);
                if ((xfer->c_flags & C_NCQ) == 0)
                        xfer->c_bio.flags |= ATA_LBA48;

                xfer->c_bio.flags |= ATA_FUA;
        }

        if (xfer->c_retries == 0)
                wd->inflight++;
        mutex_exit(&wd->sc_lock);

        /* Queue the xfer */
        wd->atabus->ata_bio(wd->drvp, xfer);

        mutex_enter(&wd->sc_lock);
}

static int
wd_diskstart(device_t dev, struct buf *bp)
{
        struct wd_softc *wd = device_private(dev);
#ifdef ATADEBUG
        struct dk_softc *dksc = &wd->sc_dksc;
#endif
        struct ata_xfer *xfer;
        struct ata_channel *chp;
        unsigned openings;
        int ticks;

        mutex_enter(&wd->sc_lock);

        chp = wd->drvp->chnl_softc;

        ata_channel_lock(chp);
        openings = ata_queue_openings(chp);
        ata_channel_unlock(chp);

        openings = uimin(openings, wd->drvp->drv_openings);

        if (wd->inflight >= openings) {
                /*
                 * pretend we run out of memory when the queue is full,
                 * so that the operation is retried after a minimal
                 * delay.
                 */
                xfer = NULL;
                ticks = 1;
        } else {
                /*
                 * If there is no available memory, retry later. This
                 * happens very rarely and only under memory pressure,
                 * so wait relatively long before retry.
                 */
                xfer = ata_get_xfer(chp, false);
                ticks = hz/2;
        }

        if (xfer == NULL) {
                ATADEBUG_PRINT(("wd_diskstart %s no xfer\n",
                    dksc->sc_xname), DEBUG_XFERS);

                /*
                 * The disk queue is pushed automatically when an I/O
                 * operation finishes or another one is queued. We
                 * need this extra timeout because an ATA channel
                 * might be shared by more than one disk queue and
                 * all queues need to be restarted when another slot
                 * becomes available.
                 */
                if (!callout_pending(&wd->sc_restart_diskqueue)) {
                        callout_reset(&wd->sc_restart_diskqueue, ticks,
                            wdrestart, dev);
                }

                mutex_exit(&wd->sc_lock);
                return EAGAIN;
        }

        wdstart1(wd, bp, xfer);

        mutex_exit(&wd->sc_lock);

        return 0;
}

/*
 * Queue a drive for I/O.
 */
static void
wdrestart(void *x)
{
        device_t self = x;
        struct wd_softc *wd = device_private(self);
        struct dk_softc *dksc = &wd->sc_dksc;

        ATADEBUG_PRINT(("wdstart %s\n", dksc->sc_xname),
            DEBUG_XFERS);

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

        dk_start(dksc, NULL);
}

static void
wddone(device_t self, struct ata_xfer *xfer)
{
        struct wd_softc *wd = device_private(self);
        struct dk_softc *dksc = &wd->sc_dksc;
        const char *errmsg;
        int do_perror = 0;
        struct buf *bp;

        ATADEBUG_PRINT(("wddone %s\n", dksc->sc_xname),
            DEBUG_XFERS);

        if (__predict_false(wddoingadump)) {
                /* just drop it to the floor */
                ata_free_xfer(wd->drvp->chnl_softc, xfer);
                return;
        }

        bp = xfer->c_bio.bp;
        KASSERT(bp != NULL);

        bp->b_resid = xfer->c_bio.bcount;
        switch (xfer->c_bio.error) {
        case ERR_DMA:
                errmsg = "DMA error";
                goto retry;
        case ERR_DF:
                errmsg = "device fault";
                goto retry;
        case TIMEOUT:
                errmsg = "device timeout";
                goto retry;
        case REQUEUE:
                errmsg = "requeue";
                goto retry2;
        case ERR_RESET:
                errmsg = "channel reset";
                goto retry2;
        case ERROR:
                /* Don't care about media change bits */
                if (xfer->c_bio.r_error != 0 &&
                    (xfer->c_bio.r_error & ~(WDCE_MC | WDCE_MCR)) == 0)
                        goto noerror;
                errmsg = "error";
                do_perror = 1;
retry:          /* Just reset and retry. Can we do more ? */
                if ((xfer->c_flags & C_RECOVERED) == 0) {
                        int wflags = (xfer->c_flags & C_POLL) ? AT_POLL : 0;
                        ata_channel_lock(wd->drvp->chnl_softc);
                        ata_thread_run(wd->drvp->chnl_softc, wflags,
                            ATACH_TH_DRIVE_RESET, wd->drvp->drive);
                        ata_channel_unlock(wd->drvp->chnl_softc);
                }
retry2:
                mutex_enter(&wd->sc_lock);

                diskerr(bp, "wd", errmsg, LOG_PRINTF,
                    xfer->c_bio.blkdone, dksc->sc_dkdev.dk_label);
                if (xfer->c_retries < WDIORETRIES)
                        printf(", xfer %"PRIxPTR", retry %d",
                            (intptr_t)xfer & PAGE_MASK,
                            xfer->c_retries);
                printf("\n");
                if (do_perror)
                        wdperror(wd, xfer);

                if (xfer->c_retries < WDIORETRIES) {
                        xfer->c_retries++;

                        /* Rerun ASAP if just requeued */
                        if (xfer->c_bio.error == REQUEUE) {
                                SLIST_INSERT_HEAD(&wd->sc_requeue_list, xfer,
                                    c_retrychain);
                                callout_reset(&wd->sc_requeue_callout,
                                    1, wdbiorequeue, wd);
                        } else {
                                SLIST_INSERT_HEAD(&wd->sc_retry_list, xfer,
                                    c_retrychain);
                                callout_reset(&wd->sc_retry_callout,
                                    RECOVERYTIME, wdbioretry, wd);
                        }

                        mutex_exit(&wd->sc_lock);
                        return;
                }

                mutex_exit(&wd->sc_lock);

#ifdef WD_SOFTBADSECT
                /*
                 * Not all errors indicate a failed block but those that do,
                 * put the block on the bad-block list for the device.  Only
                 * do this for reads because the drive should do it for writes,
                 * itself, according to Manuel.
                 */
                if ((bp->b_flags & B_READ) &&
                    ((wd->drvp->ata_vers >= 4 && xfer->c_bio.r_error & 64) ||
                     (wd->drvp->ata_vers < 4 && xfer->c_bio.r_error & 192))) {
                        struct disk_badsectors *dbs;

                        dbs = kmem_zalloc(sizeof *dbs, KM_NOSLEEP);
                        if (dbs == NULL) {
                                device_printf(dksc->sc_dev,
                                    "failed to add bad block to list\n");
                                goto out;
                        }

                        dbs->dbs_min = bp->b_rawblkno;
                        dbs->dbs_max = dbs->dbs_min +
                            (bp->b_bcount /wd->sc_blksize) - 1;
                        microtime(&dbs->dbs_failedat);

                        mutex_enter(&wd->sc_lock);
                        SLIST_INSERT_HEAD(&wd->sc_bslist, dbs, dbs_next);
                        wd->sc_bscount++;
                        mutex_exit(&wd->sc_lock);
                }
out:
#endif
                bp->b_error = EIO;
                break;
        case NOERROR:
#ifdef WD_CHAOS_MONKEY
                /*
                 * For example Parallels AHCI emulation doesn't actually
                 * return error for the invalid I/O, so just re-run
                 * the request and do not panic.
                 */
                if (__predict_false(xfer->c_flags & C_CHAOS)) {
                        xfer->c_bio.error = REQUEUE;
                        errmsg = "chaos noerror";
                        goto retry2;
                }
#endif

noerror:        if ((xfer->c_bio.flags & ATA_CORR) || xfer->c_retries > 0)
                        device_printf(dksc->sc_dev,
                            "soft error (corrected) xfer %"PRIxPTR"\n",
                            (intptr_t)xfer & PAGE_MASK);
                break;
        case ERR_NODEV:
                bp->b_error = EIO;
                break;
        }
        if (__predict_false(bp->b_error != 0) && bp->b_resid == 0) {
                /*
                 * the disk or controller sometimes report a complete
                 * xfer, when there has been an error. This is wrong,
                 * assume nothing got transferred in this case
                 */
                bp->b_resid = bp->b_bcount;
        }

        ata_free_xfer(wd->drvp->chnl_softc, xfer);

        mutex_enter(&wd->sc_lock);
        wd->inflight--;
        mutex_exit(&wd->sc_lock);
        dk_done(dksc, bp);
        dk_start(dksc, NULL);
}

static void
wdbioretry(void *v)
{
        struct wd_softc *wd = v;
        struct ata_xfer *xfer;

        ATADEBUG_PRINT(("%s %s\n", __func__, wd->sc_dksc.sc_xname),
            DEBUG_XFERS);

        mutex_enter(&wd->sc_lock);
        while ((xfer = SLIST_FIRST(&wd->sc_retry_list))) {
                SLIST_REMOVE_HEAD(&wd->sc_retry_list, c_retrychain);
                wdstart1(wd, xfer->c_bio.bp, xfer);
        }
        mutex_exit(&wd->sc_lock);
}

static void
wdbiorequeue(void *v)
{
        struct wd_softc *wd = v;
        struct ata_xfer *xfer;

        ATADEBUG_PRINT(("%s %s\n", __func__, wd->sc_dksc.sc_xname),
            DEBUG_XFERS);

        mutex_enter(&wd->sc_lock);
        while ((xfer = SLIST_FIRST(&wd->sc_requeue_list))) {
                SLIST_REMOVE_HEAD(&wd->sc_requeue_list, c_retrychain);
                wdstart1(wd, xfer->c_bio.bp, xfer);
        }
        mutex_exit(&wd->sc_lock);
}

static void
wdminphys(struct buf *bp)
{
        const struct wd_softc * const wd =
            device_lookup_private(&wd_cd, WDUNIT(bp->b_dev));
        int maxsectors;

        /*
         * The limit is actually 65536 for LBA48 and 256 for non-LBA48,
         * but that requires to set the count for the ATA command
         * to 0, which is somewhat error prone, so better stay safe.
         */
        if (wd->sc_flags & WDF_LBA48)
                maxsectors = 65535;
        else
                maxsectors = 128;

        if (bp->b_bcount > (wd->sc_blksize * maxsectors))
                bp->b_bcount = (wd->sc_blksize * maxsectors);

        minphys(bp);
}

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

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

        wdminphys(&B);

        *count = B.b_bcount;
}

static int
wdread(dev_t dev, struct uio *uio, int flags)
{

        ATADEBUG_PRINT(("wdread\n"), DEBUG_XFERS);
        return (physio(wdstrategy, NULL, dev, B_READ, wdminphys, uio));
}

static int
wdwrite(dev_t dev, struct uio *uio, int flags)
{

        ATADEBUG_PRINT(("wdwrite\n"), DEBUG_XFERS);
        return (physio(wdstrategy, NULL, dev, B_WRITE, wdminphys, uio));
}

/*
 * The bad144 table is consulted in _wdc_ata_bio_start(), which is
 * called with the channel lock held.  Thus, we must serialize using
 * that lock when manipulating anything related to the bad144 table.
 */
#define WD_BAD144_LOCK(wd)      mutex_enter(&(wd)->drvp->chnl_softc->ch_lock)
#define WD_BAD144_UNLOCK(wd)    mutex_exit(&(wd)->drvp->chnl_softc->ch_lock)

static void
wd_load_bad144(struct wd_softc *wd, dev_t dev)
{
        struct dk_softc * const dksc = &wd->sc_dksc;
        const struct disklabel * const lp = dksc->sc_dkdev.dk_label;
        struct bad144_context *bad144 = NULL;
        int error = 0;

        /*
         * We are called from wdopen() if the disklabel indicates there
         * is a bad144 table present on the disk.  We only want to attempt
         * to read the bad144 table once, on the very first open, because
         * we are going to print diagnostic information in case there is
         * some inconsistency that prevents bad144 from working.
         */

        WD_BAD144_LOCK(wd);

        if (wd->sc_tried_bad144 || wd->drvp->bad144 != NULL) {
                /*
                 * This is not the first pass through, or someone raced
                 * with us and beat us to it.
                 */
                goto out_unlock;
        }

        /* Don't hold this lock while we allocate memory and perform I/O. */
        WD_BAD144_UNLOCK(wd);

        bad144 = bad144_init(lp->d_secsize, lp->d_ncylinders, lp->d_ntracks,
            lp->d_nsectors);
        if (bad144 == NULL) {
                printf("%s: disklabel indicates BAD144 but "
                       "BAD144 not supported on this drive",
                    device_xname(dksc->sc_dev));
                goto out;
        }

        error = bad144_load(bad144, WDLABELDEV(dev), wdstrategy);
        if (error == ESRCH) {
                /* No bad144 table on this drive?? */
                printf("%s: disklabel indicates BAD144 but "
                       "BAD144 table not found",
                    device_xname(dksc->sc_dev));
        } else if (error == EINVAL) {
                printf("%s: invalid BAD144 table",
                    device_xname(dksc->sc_dev));
        } else if (error) {
                printf("%s: error %d reading BAD144 table",
                    device_xname(dksc->sc_dev), error);
        }

 out:
        WD_BAD144_LOCK(wd);
        if (bad144 != NULL && error == 0) {
                /*
                 * Don't replace the in-use table if we lost the
                 * race; the one we just read in is probably stale.
                 */
                if (wd->drvp->bad144 == NULL) {
                        wd->drvp->bad144 = bad144;
                        bad144 = NULL;
                }
        }
        wd->sc_tried_bad144 = true;

 out_unlock:
        WD_BAD144_UNLOCK(wd);
        if (bad144 != NULL) {
                bad144_fini(bad144);
        }
}

static int
wdopen(dev_t dev, int flag, int fmt, struct lwp *l)
{
        struct wd_softc *wd;
        struct dk_softc *dksc;
        int unit, part, error;

        ATADEBUG_PRINT(("wdopen\n"), DEBUG_FUNCS);
        unit = WDUNIT(dev);
        wd = device_lookup_private(&wd_cd, unit);
        if (wd == NULL)
                return (ENXIO);
        dksc = &wd->sc_dksc;

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

        part = WDPART(dev);

        if (wd->sc_capacity == 0)
                return (ENODEV);

        /*
         * If any partition is open, but the disk has been invalidated,
         * disallow further opens.
         */
        if ((wd->sc_flags & (WDF_OPEN | WDF_LOADED)) == WDF_OPEN) {
                if (part != RAW_PART || fmt != S_IFCHR)
                        return EIO;
        }

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

        /*
         * If the disklabel indicates we have a bad144 table,
         * read that in if we haven't already.
         */
        if (error == 0 &&
            (dksc->sc_dkdev.dk_label->d_flags & D_BADSECT) != 0) {
                wd_load_bad144(wd, dev);
        }

        return error;
}

/*
 * Serialized by caller
 */
static int
wd_firstopen(device_t self, dev_t dev, int flag, int fmt)
{
        struct wd_softc *wd = device_private(self);
        struct dk_softc *dksc = &wd->sc_dksc;
        int error;

        error = wd->atabus->ata_addref(wd->drvp);
        if (error)
                return error;

        if ((wd->sc_flags & WDF_LOADED) == 0) {
                int param_error;

                /* Load the physical device parameters. */
                param_error = wd_get_params(wd, &wd->sc_params);
                if (param_error != 0) {
                        aprint_error_dev(dksc->sc_dev, "IDENTIFY failed\n");
                        error = EIO;
                        goto bad;
                }
                wd_set_geometry(wd);
                wd->sc_flags |= WDF_LOADED;
        }

        wd->sc_flags |= WDF_OPEN;
        return 0;

bad:
        wd->atabus->ata_delref(wd->drvp);
        return error;
}

/*
 * Caller must hold wd->sc_dk.dk_openlock.
 */
static int
wd_lastclose(device_t self)
{
        struct wd_softc *wd = device_private(self);

        KASSERTMSG(bufq_peek(wd->sc_dksc.sc_bufq) == NULL, "bufq not empty");

        if (wd->sc_flags & WDF_DIRTY)
                wd_flushcache(wd, AT_WAIT);

        wd->atabus->ata_delref(wd->drvp);
        wd->sc_flags &= ~WDF_OPEN;

        return 0;
}

static int
wdclose(dev_t dev, int flag, int fmt, struct lwp *l)
{
        struct wd_softc *wd;
        struct dk_softc *dksc;
        int unit;

        unit = WDUNIT(dev);
        wd = device_lookup_private(&wd_cd, unit);
        dksc = &wd->sc_dksc;

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

void
wdperror(const struct wd_softc *wd, struct ata_xfer *xfer)
{
        static const char *const errstr0_3[] = {"address mark not found",
            "track 0 not found", "aborted command", "media change requested",
            "id not found", "media changed", "uncorrectable data error",
            "bad block detected"};
        static const char *const errstr4_5[] = {
            "obsolete (address mark not found)",
            "no media/write protected", "aborted command",
            "media change requested", "id not found", "media changed",
            "uncorrectable data error", "interface CRC error"};
        const char *const *errstr;
        int i;
        const char *sep = "";

        const struct dk_softc *dksc = &wd->sc_dksc;
        const char *devname = dksc->sc_xname;
        struct ata_drive_datas *drvp = wd->drvp;
        int errno = xfer->c_bio.r_error;

        if (drvp->ata_vers >= 4)
                errstr = errstr4_5;
        else
                errstr = errstr0_3;

        printf("%s: (", devname);

        if (errno == 0)
                printf("error not notified");

        for (i = 0; i < 8; i++) {
                if (errno & (1 << i)) {
                        printf("%s%s", sep, errstr[i]);
                        sep = ", ";
                }
        }
        printf(")\n");
}

static int
wd_diocsbad(struct wd_softc *wd, const struct dkbad *dkb)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        const struct disklabel * const lp = dksc->sc_dkdev.dk_label;
        struct bad144_context *bad144, *obad144;
        int error;

        bad144 = bad144_init(lp->d_secsize, lp->d_ncylinders, lp->d_ntracks,
            lp->d_nsectors);
        if (bad144 == NULL) {
                return ENOTSUP;
        }

        error = bad144_set(bad144, dkb);
        if (error) {
                bad144_fini(bad144);
                return error;
        }

        WD_BAD144_LOCK(wd);
        obad144 = wd->drvp->bad144;
        wd->drvp->bad144 = bad144;
        WD_BAD144_UNLOCK(wd);

        if (obad144 != NULL) {
                bad144_fini(obad144);
        }

        return 0;
}

int
wdioctl(dev_t dev, u_long cmd, void *addr, int flag, struct lwp *l)
{
        struct wd_softc *wd =
            device_lookup_private(&wd_cd, WDUNIT(dev));
        struct dk_softc *dksc = &wd->sc_dksc;

        ATADEBUG_PRINT(("wdioctl\n"), DEBUG_FUNCS);

        if ((wd->sc_flags & WDF_LOADED) == 0)
                return EIO;

        switch (cmd) {
        case DIOCSBAD:
                if ((flag & FWRITE) == 0)
                        return EBADF;
                return wd_diocsbad(wd, (struct dkbad *)addr);

#ifdef WD_SOFTBADSECT
        case DIOCBSLIST: {
                uint32_t count, missing, skip;
                struct disk_badsecinfo dbsi;
                struct disk_badsectors *dbs, dbsbuf;
                size_t available;
                uint8_t *laddr;
                int error;

                dbsi = *(struct disk_badsecinfo *)addr;
                missing = wd->sc_bscount;
                count = 0;
                available = dbsi.dbsi_bufsize;
                skip = dbsi.dbsi_skip;
                laddr = (uint8_t *)dbsi.dbsi_buffer;

                /*
                 * We start this loop with the expectation that all of the
                 * entries will be missed and decrement this counter each
                 * time we either skip over one (already copied out) or
                 * we actually copy it back to user space.  The structs
                 * holding the bad sector information are copied directly
                 * back to user space whilst the summary is returned via
                 * the struct passed in via the ioctl.
                 */
                error = 0;
                mutex_enter(&wd->sc_lock);
                wd->sc_bslist_inuse++;
                SLIST_FOREACH(dbs, &wd->sc_bslist, dbs_next) {
                        if (skip > 0) {
                                missing--;
                                skip--;
                                continue;
                        }
                        if (available < sizeof(*dbs))
                                break;
                        available -= sizeof(*dbs);
                        memset(&dbsbuf, 0, sizeof(dbsbuf));
                        dbsbuf.dbs_min = dbs->dbs_min;
                        dbsbuf.dbs_max = dbs->dbs_max;
                        dbsbuf.dbs_failedat = dbs->dbs_failedat;
                        mutex_exit(&wd->sc_lock);
                        error = copyout(&dbsbuf, laddr, sizeof(dbsbuf));
                        mutex_enter(&wd->sc_lock);
                        if (error)
                                break;
                        laddr += sizeof(*dbs);
                        missing--;
                        count++;
                }
                if (--wd->sc_bslist_inuse == 0)
                        cv_broadcast(&wd->sc_bslist_cv);
                mutex_exit(&wd->sc_lock);
                dbsi.dbsi_left = missing;
                dbsi.dbsi_copied = count;
                *(struct disk_badsecinfo *)addr = dbsi;

                /*
                 * If we copied anything out, ignore error and return
                 * success -- can't back it out.
                 */
                return count ? 0 : error;
        }

        case DIOCBSFLUSH: {
                int error;

                /* Clean out the bad sector list */
                mutex_enter(&wd->sc_lock);
                while (wd->sc_bslist_inuse) {
                        error = cv_wait_sig(&wd->sc_bslist_cv, &wd->sc_lock);
                        if (error) {
                                mutex_exit(&wd->sc_lock);
                                return error;
                        }
                }
                while (!SLIST_EMPTY(&wd->sc_bslist)) {
                        struct disk_badsectors *dbs =
                            SLIST_FIRST(&wd->sc_bslist);
                        SLIST_REMOVE_HEAD(&wd->sc_bslist, dbs_next);
                        mutex_exit(&wd->sc_lock);
                        kmem_free(dbs, sizeof(*dbs));
                        mutex_enter(&wd->sc_lock);
                }
                mutex_exit(&wd->sc_lock);
                wd->sc_bscount = 0;
                return 0;
        }
#endif

#ifdef notyet
        case DIOCWFORMAT:
                if ((flag & FWRITE) == 0)
                        return EBADF;
                {
                register struct format_op *fop;
                struct iovec aiov;
                struct uio auio;
                int error1;

                fop = (struct format_op *)addr;
                aiov.iov_base = fop->df_buf;
                aiov.iov_len = fop->df_count;
                auio.uio_iov = &aiov;
                auio.uio_iovcnt = 1;
                auio.uio_resid = fop->df_count;
                auio.uio_offset =
                        fop->df_startblk * wd->sc_dk.dk_label->d_secsize;
                auio.uio_vmspace = l->l_proc->p_vmspace;
                error1 = physio(wdformat, NULL, dev, B_WRITE, wdminphys,
                    &auio);
                fop->df_count -= auio.uio_resid;
                fop->df_reg[0] = wdc->sc_status;
                fop->df_reg[1] = wdc->sc_error;
                return error1;
                }
#endif
        case DIOCGCACHE:
                return wd_getcache(wd, (int *)addr);

        case DIOCSCACHE:
                return wd_setcache(wd, *(int *)addr);

        case DIOCCACHESYNC:
                return wd_flushcache(wd, AT_WAIT);

        case ATAIOCCOMMAND:
                /*
                 * Make sure this command is (relatively) safe first
                 */
                if ((((atareq_t *) addr)->flags & ATACMD_READ) == 0 &&
                    (flag & FWRITE) == 0)
                        return (EBADF);
                {
                struct wd_ioctl *wi;
                atareq_t *atareq = (atareq_t *) addr;
                int error1;

                wi = wi_get(wd);
                wi->wi_atareq = *atareq;

                if (atareq->datalen && atareq->flags &
                    (ATACMD_READ | ATACMD_WRITE)) {
                        void *tbuf;
                        if (atareq->datalen < DEV_BSIZE
                            && atareq->command == WDCC_IDENTIFY) {
                                tbuf = kmem_zalloc(DEV_BSIZE, KM_SLEEP);
                                wi->wi_iov.iov_base = tbuf;
                                wi->wi_iov.iov_len = DEV_BSIZE;
                                UIO_SETUP_SYSSPACE(&wi->wi_uio);
                        } else {
                                tbuf = NULL;
                                wi->wi_iov.iov_base = atareq->databuf;
                                wi->wi_iov.iov_len = atareq->datalen;
                                wi->wi_uio.uio_vmspace = l->l_proc->p_vmspace;
                        }
                        wi->wi_uio.uio_iov = &wi->wi_iov;
                        wi->wi_uio.uio_iovcnt = 1;
                        wi->wi_uio.uio_resid = atareq->datalen;
                        wi->wi_uio.uio_offset = 0;
                        wi->wi_uio.uio_rw =
                            (atareq->flags & ATACMD_READ) ? B_READ : B_WRITE;
                        error1 = physio(wdioctlstrategy, &wi->wi_bp, dev,
                            (atareq->flags & ATACMD_READ) ? B_READ : B_WRITE,
                            wdminphys, &wi->wi_uio);
                        if (tbuf != NULL && error1 == 0) {
                                error1 = copyout(tbuf, atareq->databuf,
                                    atareq->datalen);
                                kmem_free(tbuf, DEV_BSIZE);
                        }
                } else {
                        /* No need to call physio if we don't have any
                           user data */
                        wi->wi_bp.b_flags = 0;
                        wi->wi_bp.b_data = 0;
                        wi->wi_bp.b_bcount = 0;
                        wi->wi_bp.b_dev = dev;
                        wi->wi_bp.b_proc = l->l_proc;
                        wdioctlstrategy(&wi->wi_bp);
                        error1 = wi->wi_bp.b_error;
                }
                *atareq = wi->wi_atareq;
                wi_free(wi);
                return(error1);
                }

        default:
                return dk_ioctl(dksc, dev, cmd, addr, flag, l);
        }

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

static int
wd_discard(device_t dev, off_t pos, off_t len)
{
        struct wd_softc *wd = device_private(dev);
        daddr_t bno;
        long size, done;
        long maxatonce, amount;
        int result;

        if (!(wd->sc_params.atap_ata_major & WDC_VER_ATA7)
            || !(wd->sc_params.support_dsm & ATA_SUPPORT_DSM_TRIM)) {
                /* not supported; ignore request */
                ATADEBUG_PRINT(("wddiscard (unsupported)\n"), DEBUG_FUNCS);
                return 0;
        }
        maxatonce = 0xffff; /*wd->sc_params.max_dsm_blocks*/

        ATADEBUG_PRINT(("wddiscard\n"), DEBUG_FUNCS);

        if ((wd->sc_flags & WDF_LOADED) == 0)
                return EIO;

        /* round the start up and the end down */
        bno = (pos + wd->sc_blksize - 1) / wd->sc_blksize;
        size = ((pos + len) / wd->sc_blksize) - bno;

        done = 0;
        while (done < size) {
             amount = size - done;
             if (amount > maxatonce) {
                     amount = maxatonce;
             }
             result = wd_trim(wd, bno + done, amount);
             if (result) {
                     return result;
             }
             done += amount;
        }
        return 0;
}

static int
wddiscard(dev_t dev, off_t pos, off_t len)
{
        struct wd_softc *wd;
        struct dk_softc *dksc;
        int unit;

        unit = WDUNIT(dev);
        wd = device_lookup_private(&wd_cd, unit);
        dksc = &wd->sc_dksc;

        return dk_discard(dksc, dev, pos, len);
}

#ifdef B_FORMAT
int
wdformat(struct buf *bp)
{

        bp->b_flags |= B_FORMAT;
        return wdstrategy(bp);
}
#endif

int
wdsize(dev_t dev)
{
        struct wd_softc *wd;
        struct dk_softc *dksc;
        int unit;

        ATADEBUG_PRINT(("wdsize\n"), DEBUG_FUNCS);

        unit = WDUNIT(dev);
        wd = device_lookup_private(&wd_cd, unit);
        if (wd == NULL)
                return (-1);
        dksc = &wd->sc_dksc;

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

        return dk_size(dksc, dev);
}

/*
 * Dump core after a system crash.
 */
static int
wddump(dev_t dev, daddr_t blkno, void *va, size_t size)
{
        struct wd_softc *wd;
        struct dk_softc *dksc;
        int unit;

        /* Check if recursive dump; if so, punt. */
        if (wddoingadump)
                return EFAULT;
        wddoingadump = 1;

        unit = WDUNIT(dev);
        wd = device_lookup_private(&wd_cd, unit);
        if (wd == NULL)
                return (ENXIO);
        dksc = &wd->sc_dksc;

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

static int
wd_dumpblocks(device_t dev, void *va, daddr_t blkno, int nblk)
{
        struct wd_softc *wd = device_private(dev);
        struct dk_softc *dksc = &wd->sc_dksc;
        struct disk_geom *dg = &dksc->sc_dkdev.dk_geom;
        struct ata_xfer *xfer = &wd->dump_xfer;
        int err;

        /* Recalibrate, if first dump transfer. */
        if (wddumprecalibrated == 0) {
                wddumprecalibrated = 1;
                ata_channel_lock(wd->drvp->chnl_softc);
                /* This will directly execute the reset due to AT_POLL */
                ata_thread_run(wd->drvp->chnl_softc, AT_POLL,
                    ATACH_TH_DRIVE_RESET, wd->drvp->drive);

                wd->drvp->state = RESET;
                ata_channel_unlock(wd->drvp->chnl_softc);
        }

        memset(xfer, 0, sizeof(*xfer));
        xfer->c_flags |= C_PRIVATE_ALLOC | C_SKIP_QUEUE;

        xfer->c_bio.blkno = blkno;
        xfer->c_bio.flags = ATA_POLL;
        if (wd->sc_flags & WDF_LBA48 &&
            (xfer->c_bio.blkno + nblk) > wd->sc_capacity28)
                xfer->c_bio.flags |= ATA_LBA48;
        if (wd->sc_flags & WDF_LBA)
                xfer->c_bio.flags |= ATA_LBA;
        xfer->c_bio.bcount = nblk * dg->dg_secsize;
        xfer->c_bio.databuf = va;
#ifndef WD_DUMP_NOT_TRUSTED
        /* This will poll until the bio is complete */
        wd->atabus->ata_bio(wd->drvp, xfer);

        switch(err = xfer->c_bio.error) {
        case TIMEOUT:
                printf("wddump: device timed out");
                err = EIO;
                break;
        case ERR_DF:
                printf("wddump: drive fault");
                err = EIO;
                break;
        case ERR_DMA:
                printf("wddump: DMA error");
                err = EIO;
                break;
        case ERROR:
                printf("wddump: ");
                wdperror(wd, xfer);
                err = EIO;
                break;
        case NOERROR:
                err = 0;
                break;
        default:
                panic("wddump: unknown error type %x", err);
        }

        if (err != 0) {
                printf("\n");
                return err;
        }
#else   /* WD_DUMP_NOT_TRUSTED */
        /* Let's just talk about this first... */
        printf("wd%d: dump addr 0x%x, cylin %d, head %d, sector %d\n",
            unit, va, cylin, head, sector);
        delay(500 * 1000);      /* half a second */
#endif

        wddoingadump = 0;
        return 0;
}

static void
wd_set_geometry(struct wd_softc *wd)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        struct disk_geom *dg = &dksc->sc_dkdev.dk_geom;

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

        dg->dg_secperunit = wd->sc_capacity;
        dg->dg_secsize = wd->sc_blksize;
        dg->dg_nsectors = wd->sc_params.atap_sectors;
        dg->dg_ntracks = wd->sc_params.atap_heads;
        if ((wd->sc_flags & WDF_LBA) == 0)
                dg->dg_ncylinders = wd->sc_params.atap_cylinders;
        if ((wd->sc_params.atap_secsz & ATA_SECSZ_VALID_MASK) == ATA_SECSZ_VALID
            && ((wd->sc_params.atap_secsz & ATA_SECSZ_LPS) != 0)) {
                dg->dg_physsecsize = wd->sc_blksize << (wd->sc_params.atap_secsz &
                    ATA_SECSZ_LPS_SZMSK);
                if ((wd->sc_params.atap_logical_align & ATA_LA_VALID_MASK) ==
                    ATA_LA_VALID) {
                        dg->dg_alignedsec = (wd->sc_params.atap_logical_align &
                            ATA_LA_MASK) & ((1u << (wd->sc_params.atap_secsz &
                            ATA_SECSZ_LPS_SZMSK)) - 1);
                }
        }

        disk_set_info(dksc->sc_dev, &dksc->sc_dkdev, wd->sc_typename);
}

int
wd_get_params(struct wd_softc *wd, struct ataparams *params)
{
        int retry = 0;
        struct ata_channel *chp = wd->drvp->chnl_softc;
        const int flags = AT_WAIT;

again:
        switch (wd->atabus->ata_get_params(wd->drvp, flags, params)) {
        case CMD_AGAIN:
                return 1;
        case CMD_ERR:
                if (retry == 0) {
                        retry++;
                        ata_channel_lock(chp);
                        (*wd->atabus->ata_reset_drive)(wd->drvp, flags, NULL);
                        ata_channel_unlock(chp);
                        goto again;
                }

                if (wd->drvp->drive_type != ATA_DRIVET_OLD)
                        return 1;
                /*
                 * We `know' there's a drive here; just assume it's old.
                 * This geometry is only used to read the MBR and print a
                 * (false) attach message.
                 */
                strncpy(params->atap_model, "ST506",
                    sizeof params->atap_model);
                params->atap_config = ATA_CFG_FIXED;
                params->atap_cylinders = 1024;
                params->atap_heads = 8;
                params->atap_sectors = 17;
                params->atap_multi = 1;
                params->atap_capabilities1 = params->atap_capabilities2 = 0;
                wd->drvp->ata_vers = -1; /* Mark it as pre-ATA */
                /* FALLTHROUGH */
        case CMD_OK:
                return 0;
        default:
                panic("wd_get_params: bad return code from ata_get_params");
                /* NOTREACHED */
        }
}

int
wd_getcache(struct wd_softc *wd, int *bitsp)
{
        struct ataparams params;

        if (wd_get_params(wd, &params) != 0)
                return EIO;
        if (params.atap_cmd_set1 == 0x0000 ||
            params.atap_cmd_set1 == 0xffff ||
            (params.atap_cmd_set1 & WDC_CMD1_CACHE) == 0) {
                *bitsp = 0;
                return 0;
        }
        *bitsp = DKCACHE_WCHANGE | DKCACHE_READ;
        if (params.atap_cmd1_en & WDC_CMD1_CACHE)
                *bitsp |= DKCACHE_WRITE;

        if (WD_USE_NCQ(wd) || (wd->drvp->drive_flags & ATA_DRIVE_WFUA))
                *bitsp |= DKCACHE_FUA;

        return 0;
}


static int
wd_check_error(const struct dk_softc *dksc, const struct ata_xfer *xfer,
    const char *func)
{
        static const char at_errbits[] = "\20\10ERROR\11TIMEOU\12DF";

        int flags = xfer->c_ata_c.flags;

        if ((flags & AT_ERROR) != 0 && xfer->c_ata_c.r_error == WDCE_ABRT) {
                /* command not supported */
                aprint_debug_dev(dksc->sc_dev, "%s: not supported\n", func);
                return ENODEV;
        }
        if (flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
                char sbuf[sizeof(at_errbits) + 64];
                snprintb(sbuf, sizeof(sbuf), at_errbits, flags);
                device_printf(dksc->sc_dev, "%s: status=%s\n", func, sbuf);
                return EIO;
        }
        return 0;
}

int
wd_setcache(struct wd_softc *wd, int bits)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        struct ataparams params;
        struct ata_xfer *xfer;
        int error;

        if (wd_get_params(wd, &params) != 0)
                return EIO;

        if (params.atap_cmd_set1 == 0x0000 ||
            params.atap_cmd_set1 == 0xffff ||
            (params.atap_cmd_set1 & WDC_CMD1_CACHE) == 0)
                return EOPNOTSUPP;

        if ((bits & DKCACHE_READ) == 0 ||
            (bits & DKCACHE_SAVE) != 0)
                return EOPNOTSUPP;

        xfer = ata_get_xfer(wd->drvp->chnl_softc, true);

        xfer->c_ata_c.r_command = SET_FEATURES;
        xfer->c_ata_c.r_st_bmask = 0;
        xfer->c_ata_c.r_st_pmask = 0;
        xfer->c_ata_c.timeout = 30000; /* 30s timeout */
        xfer->c_ata_c.flags = AT_WAIT;
        if (bits & DKCACHE_WRITE)
                xfer->c_ata_c.r_features = WDSF_WRITE_CACHE_EN;
        else
                xfer->c_ata_c.r_features = WDSF_WRITE_CACHE_DS;

        wd->atabus->ata_exec_command(wd->drvp, xfer);
        ata_wait_cmd(wd->drvp->chnl_softc, xfer);

        error = wd_check_error(dksc, xfer, __func__);
        ata_free_xfer(wd->drvp->chnl_softc, xfer);
        return error;
}

static int
wd_standby(struct wd_softc *wd, int flags)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        struct ata_xfer *xfer;
        int error;

        aprint_debug_dev(dksc->sc_dev, "standby immediate\n");
        xfer = ata_get_xfer(wd->drvp->chnl_softc, true);

        xfer->c_ata_c.r_command = WDCC_STANDBY_IMMED;
        xfer->c_ata_c.r_st_bmask = WDCS_DRDY;
        xfer->c_ata_c.r_st_pmask = WDCS_DRDY;
        xfer->c_ata_c.flags = flags;
        xfer->c_ata_c.timeout = 30000; /* 30s timeout */

        wd->atabus->ata_exec_command(wd->drvp, xfer);
        ata_wait_cmd(wd->drvp->chnl_softc, xfer);

        error = wd_check_error(dksc, xfer, __func__);
        ata_free_xfer(wd->drvp->chnl_softc, xfer);
        return error;
}

int
wd_flushcache(struct wd_softc *wd, int flags)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        struct ata_xfer *xfer;
        int error;

        /*
         * WDCC_FLUSHCACHE is here since ATA-4, but some drives report
         * only ATA-2 and still support it.
         */
        if (wd->drvp->ata_vers < 4 &&
            ((wd->sc_params.atap_cmd_set2 & WDC_CMD2_FC) == 0 ||
            wd->sc_params.atap_cmd_set2 == 0xffff))
                return ENODEV;

        xfer = ata_get_xfer(wd->drvp->chnl_softc, true);

        if ((wd->sc_params.atap_cmd2_en & ATA_CMD2_LBA48) != 0 &&
            (wd->sc_params.atap_cmd2_en & ATA_CMD2_FCE) != 0) {
                xfer->c_ata_c.r_command = WDCC_FLUSHCACHE_EXT;
                flags |= AT_LBA48;
        } else
                xfer->c_ata_c.r_command = WDCC_FLUSHCACHE;
        xfer->c_ata_c.r_st_bmask = WDCS_DRDY;
        xfer->c_ata_c.r_st_pmask = WDCS_DRDY;
        xfer->c_ata_c.flags = flags | AT_READREG;
        xfer->c_ata_c.timeout = 300000; /* 5m timeout */

        wd->atabus->ata_exec_command(wd->drvp, xfer);
        ata_wait_cmd(wd->drvp->chnl_softc, xfer);

        error = wd_check_error(dksc, xfer, __func__);
        wd->sc_flags &= ~WDF_DIRTY;
        ata_free_xfer(wd->drvp->chnl_softc, xfer);
        return error;
}

/*
 * Execute TRIM command, assumes sleep context.
 */
static int
wd_trim(struct wd_softc *wd, daddr_t bno, long size)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        struct ata_xfer *xfer;
        int error;
        unsigned char *req;

        xfer = ata_get_xfer(wd->drvp->chnl_softc, true);

        req = kmem_zalloc(512, KM_SLEEP);
        req[0] = bno & 0xff;
        req[1] = (bno >> 8) & 0xff;
        req[2] = (bno >> 16) & 0xff;
        req[3] = (bno >> 24) & 0xff;
        req[4] = (bno >> 32) & 0xff;
        req[5] = (bno >> 40) & 0xff;
        req[6] = size & 0xff;
        req[7] = (size >> 8) & 0xff;

        /*
         * XXX We could possibly use NCQ TRIM, which supports executing
         * this command concurrently. It would need some investigation, some
         * early or not so early disk firmware caused data loss with NCQ TRIM.
         * atastart() et.al would need to be adjusted to allow and support
         * running several non-I/O ATA commands in parallel.
         */

        xfer->c_ata_c.r_command = ATA_DATA_SET_MANAGEMENT;
        xfer->c_ata_c.r_count = 1;
        xfer->c_ata_c.r_features = ATA_SUPPORT_DSM_TRIM;
        xfer->c_ata_c.r_st_bmask = WDCS_DRDY;
        xfer->c_ata_c.r_st_pmask = WDCS_DRDY;
        xfer->c_ata_c.timeout = 30000; /* 30s timeout */
        xfer->c_ata_c.data = req;
        xfer->c_ata_c.bcount = 512;
        xfer->c_ata_c.flags |= AT_WRITE | AT_WAIT;

        wd->atabus->ata_exec_command(wd->drvp, xfer);
        ata_wait_cmd(wd->drvp->chnl_softc, xfer);

        kmem_free(req, 512);
        error = wd_check_error(dksc, xfer, __func__);
        ata_free_xfer(wd->drvp->chnl_softc, xfer);
        return error;
}

bool
wd_shutdown(device_t dev, int how)
{
        struct wd_softc *wd = device_private(dev);

        /* the adapter needs to be enabled */
        if (wd->atabus->ata_addref(wd->drvp))
                return true; /* no need to complain */

        wd_flushcache(wd, AT_POLL);
        if ((how & RB_POWERDOWN) == RB_POWERDOWN)
                wd_standby(wd, AT_POLL);
        return true;
}

/*
 * Allocate space for a ioctl queue structure.  Mostly taken from
 * scsipi_ioctl.c
 */
struct wd_ioctl *
wi_get(struct wd_softc *wd)
{
        struct wd_ioctl *wi;

        wi = kmem_zalloc(sizeof(struct wd_ioctl), KM_SLEEP);
        wi->wi_softc = wd;
        buf_init(&wi->wi_bp);

        return (wi);
}

/*
 * Free an ioctl structure and remove it from our list
 */

void
wi_free(struct wd_ioctl *wi)
{
        buf_destroy(&wi->wi_bp);
        kmem_free(wi, sizeof(*wi));
}

/*
 * Find a wd_ioctl structure based on the struct buf.
 */

struct wd_ioctl *
wi_find(struct buf *bp)
{
        return container_of(bp, struct wd_ioctl, wi_bp);
}

static uint
wi_sector_size(const struct wd_ioctl * const wi)
{
        switch (wi->wi_atareq.command) {
        case WDCC_READ:
        case WDCC_WRITE:
        case WDCC_READMULTI:
        case WDCC_WRITEMULTI:
        case WDCC_READDMA:
        case WDCC_WRITEDMA:
        case WDCC_READ_EXT:
        case WDCC_WRITE_EXT:
        case WDCC_READMULTI_EXT:
        case WDCC_WRITEMULTI_EXT:
        case WDCC_READDMA_EXT:
        case WDCC_WRITEDMA_EXT:
        case WDCC_READ_FPDMA_QUEUED:
        case WDCC_WRITE_FPDMA_QUEUED:
                return wi->wi_softc->sc_blksize;
        default:
                return 512;
        }
}

/*
 * Ioctl pseudo strategy routine
 *
 * This is mostly stolen from scsipi_ioctl.c:scsistrategy().  What
 * happens here is:
 *
 * - wdioctl() queues a wd_ioctl structure.
 *
 * - wdioctl() calls physio/wdioctlstrategy based on whether or not
 *   user space I/O is required.  If physio() is called, physio() eventually
 *   calls wdioctlstrategy().
 *
 * - In either case, wdioctlstrategy() calls wd->atabus->ata_exec_command()
 *   to perform the actual command
 *
 * The reason for the use of the pseudo strategy routine is because
 * when doing I/O to/from user space, physio _really_ wants to be in
 * the loop.  We could put the entire buffer into the ioctl request
 * structure, but that won't scale if we want to do things like download
 * microcode.
 */

void
wdioctlstrategy(struct buf *bp)
{
        struct wd_ioctl *wi;
        struct ata_xfer *xfer;
        int error = 0;

        wi = wi_find(bp);
        if (wi == NULL) {
                printf("wdioctlstrategy: "
                    "No matching ioctl request found in queue\n");
                error = EINVAL;
                goto out2;
        }

        xfer = ata_get_xfer(wi->wi_softc->drvp->chnl_softc, true);

        /*
         * Abort if physio broke up the transfer
         */

        if (bp->b_bcount != wi->wi_atareq.datalen) {
                printf("physio split wd ioctl request... cannot proceed\n");
                error = EIO;
                goto out;
        }

        /*
         * Abort if we didn't get a buffer size that was a multiple of
         * our sector size (or overflows CHS/LBA28 sector count)
         */

        if ((bp->b_bcount % wi_sector_size(wi)) != 0 ||
            (bp->b_bcount / wi_sector_size(wi)) >=
             (1 << NBBY)) {
                error = EINVAL;
                goto out;
        }

        /*
         * Make sure a timeout was supplied in the ioctl request
         */

        if (wi->wi_atareq.timeout == 0) {
                error = EINVAL;
                goto out;
        }

        if (wi->wi_atareq.flags & ATACMD_READ)
                xfer->c_ata_c.flags |= AT_READ;
        else if (wi->wi_atareq.flags & ATACMD_WRITE)
                xfer->c_ata_c.flags |= AT_WRITE;

        if (wi->wi_atareq.flags & ATACMD_READREG)
                xfer->c_ata_c.flags |= AT_READREG;

        if ((wi->wi_atareq.flags & ATACMD_LBA) != 0)
                xfer->c_ata_c.flags |= AT_LBA;

        xfer->c_ata_c.flags |= AT_WAIT;

        xfer->c_ata_c.timeout = wi->wi_atareq.timeout;
        xfer->c_ata_c.r_command = wi->wi_atareq.command;
        xfer->c_ata_c.r_lba = ((wi->wi_atareq.head & 0x0f) << 24) |
            (wi->wi_atareq.cylinder << 8) |
            wi->wi_atareq.sec_num;
        xfer->c_ata_c.r_count = wi->wi_atareq.sec_count;
        xfer->c_ata_c.r_features = wi->wi_atareq.features;
        xfer->c_ata_c.r_st_bmask = WDCS_DRDY;
        xfer->c_ata_c.r_st_pmask = WDCS_DRDY;
        xfer->c_ata_c.data = wi->wi_bp.b_data;
        xfer->c_ata_c.bcount = wi->wi_bp.b_bcount;

        wi->wi_softc->atabus->ata_exec_command(wi->wi_softc->drvp, xfer);
        ata_wait_cmd(wi->wi_softc->drvp->chnl_softc, xfer);

        if (xfer->c_ata_c.flags & (AT_ERROR | AT_TIMEOU | AT_DF)) {
                if (xfer->c_ata_c.flags & AT_ERROR) {
                        wi->wi_atareq.retsts = ATACMD_ERROR;
                        wi->wi_atareq.error = xfer->c_ata_c.r_error;
                } else if (xfer->c_ata_c.flags & AT_DF)
                        wi->wi_atareq.retsts = ATACMD_DF;
                else
                        wi->wi_atareq.retsts = ATACMD_TIMEOUT;
        } else {
                wi->wi_atareq.retsts = ATACMD_OK;
                if (wi->wi_atareq.flags & ATACMD_READREG) {
                        wi->wi_atareq.command = xfer->c_ata_c.r_status;
                        wi->wi_atareq.features = xfer->c_ata_c.r_error;
                        wi->wi_atareq.sec_count = xfer->c_ata_c.r_count;
                        wi->wi_atareq.sec_num = xfer->c_ata_c.r_lba & 0xff;
                        wi->wi_atareq.head = (xfer->c_ata_c.r_device & 0xf0) |
                            ((xfer->c_ata_c.r_lba >> 24) & 0x0f);
                        wi->wi_atareq.cylinder =
                            (xfer->c_ata_c.r_lba >> 8) & 0xffff;
                        wi->wi_atareq.error = xfer->c_ata_c.r_error;
                }
        }

out:
        ata_free_xfer(wi->wi_softc->drvp->chnl_softc, xfer);
out2:
        bp->b_error = error;
        if (error)
                bp->b_resid = bp->b_bcount;
        biodone(bp);
}

static void
wd_sysctl_attach(struct wd_softc *wd)
{
        struct dk_softc *dksc = &wd->sc_dksc;
        const struct sysctlnode *node;
        int error;

        /* sysctl set-up */
        if (sysctl_createv(&wd->nodelog, 0, NULL, &node,
                                0, CTLTYPE_NODE, dksc->sc_xname,
                                SYSCTL_DESCR("wd driver settings"),
                                NULL, 0, NULL, 0,
                                CTL_HW, CTL_CREATE, CTL_EOL) != 0) {
                aprint_error_dev(dksc->sc_dev,
                    "could not create %s.%s sysctl node\n",
                    "hw", dksc->sc_xname);
                return;
        }

        wd->drv_ncq = true;
        if ((error = sysctl_createv(&wd->nodelog, 0, NULL, NULL,
                                CTLFLAG_READWRITE, CTLTYPE_BOOL, "use_ncq",
                                SYSCTL_DESCR("use NCQ if supported"),
                                NULL, 0, &wd->drv_ncq, 0,
                                CTL_HW, node->sysctl_num, CTL_CREATE, CTL_EOL))
                                != 0) {
                aprint_error_dev(dksc->sc_dev,
                    "could not create %s.%s.use_ncq sysctl - error %d\n",
                    "hw", dksc->sc_xname, error);
                return;
        }

        wd->drv_ncq_prio = false;
        if ((error = sysctl_createv(&wd->nodelog, 0, NULL, NULL,
                                CTLFLAG_READWRITE, CTLTYPE_BOOL, "use_ncq_prio",
                                SYSCTL_DESCR("use NCQ PRIORITY if supported"),
                                NULL, 0, &wd->drv_ncq_prio, 0,
                                CTL_HW, node->sysctl_num, CTL_CREATE, CTL_EOL))
                                != 0) {
                aprint_error_dev(dksc->sc_dev,
                    "could not create %s.%s.use_ncq_prio sysctl - error %d\n",
                    "hw", dksc->sc_xname, error);
                return;
        }

#ifdef WD_CHAOS_MONKEY
        wd->drv_chaos_freq = 0;
        if ((error = sysctl_createv(&wd->nodelog, 0, NULL, NULL,
                                CTLFLAG_READWRITE, CTLTYPE_INT, "chaos_freq",
                                SYSCTL_DESCR("simulated bio read error rate"),
                                NULL, 0, &wd->drv_chaos_freq, 0,
                                CTL_HW, node->sysctl_num, CTL_CREATE, CTL_EOL))
                                != 0) {
                aprint_error_dev(dksc->sc_dev,
                    "could not create %s.%s.chaos_freq sysctl - error %d\n",
                    "hw", dksc->sc_xname, error);
                return;
        }

        wd->drv_chaos_cnt = 0;
        if ((error = sysctl_createv(&wd->nodelog, 0, NULL, NULL,
                                CTLFLAG_READONLY, CTLTYPE_INT, "chaos_cnt",
                                SYSCTL_DESCR("number of processed bio reads"),
                                NULL, 0, &wd->drv_chaos_cnt, 0,
                                CTL_HW, node->sysctl_num, CTL_CREATE, CTL_EOL))
                                != 0) {
                aprint_error_dev(dksc->sc_dev,
                    "could not create %s.%s.chaos_cnt sysctl - error %d\n",
                    "hw", dksc->sc_xname, error);
                return;
        }
#endif

}

static void
wd_sysctl_detach(struct wd_softc *wd)
{
        sysctl_teardown(&wd->nodelog);
}

#ifdef ATADEBUG
int wddebug(void);

int
wddebug(void)
{
        struct wd_softc *wd;
          struct dk_softc *dksc;
          int unit;

          for (unit = 0; unit <= 3; unit++) {
                    wd = device_lookup_private(&wd_cd, unit);
                    if (wd == NULL)
                                continue;
                    dksc = &wd->sc_dksc;
                printf("%s fl %x bufq %p:\n",
                    dksc->sc_xname, wd->sc_flags, bufq_peek(dksc->sc_bufq));

                atachannel_debug(wd->drvp->chnl_softc);
        }
        return 0;
}
#endif /* ATADEBUG */