/*      $OpenBSD: subr_disk.c,v 1.284 2025/11/17 14:27:43 jsg Exp $     */
/*      $NetBSD: subr_disk.c,v 1.17 1996/03/16 23:17:08 christos Exp $  */

/*
 * Copyright (c) 1995 Jason R. Thorpe.  All rights reserved.
 * Copyright (c) 1982, 1986, 1988, 1993
 *      The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *      @(#)ufs_disksubr.c      8.5 (Berkeley) 1/21/94
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/fcntl.h>
#include <sys/buf.h>
#include <sys/stat.h>
#include <sys/syslog.h>
#include <sys/device.h>
#include <sys/time.h>
#include <sys/disklabel.h>
#include <sys/conf.h>
#include <sys/disk.h>
#include <sys/reboot.h>
#include <sys/dkio.h>
#include <sys/vnode.h>
#include <sys/task.h>
#include <sys/stdint.h>

#include <sys/socket.h>

#include <net/if.h>

#include <dev/cons.h>

#include <lib/libz/zlib.h>

#include "softraid.h"

#ifdef DEBUG
#define DPRINTF(x...)   printf(x)
#else
#define DPRINTF(x...)
#endif

/*
 * A global list of all disks attached to the system.  May grow or
 * shrink over time.
 */
struct  disklist_head disklist; /* TAILQ_HEAD */
int     disk_count;             /* number of drives in global disklist */
int     disk_change;            /* set if a disk has been attached/detached
                                 * since last we looked at this variable. This
                                 * is reset by hw_sysctl()
                                 */

#define DUID_SIZE 8

u_char  bootduid[DUID_SIZE];    /* DUID of boot disk. */
u_char  rootduid[DUID_SIZE];    /* DUID of root disk. */

struct device *rootdv;

/* softraid callback, do not use! */
void (*softraid_disk_attach)(struct disk *, int);

void sr_map_root(void);

struct disk_attach_task {
        struct task task;
        struct disk *dk;
};

void disk_attach_callback(void *);

int spoofgpt(struct buf *, void (*)(struct buf *), const uint8_t *,
    struct disklabel *, daddr_t *);
void spoofmbr(struct buf *, void (*)(struct buf *), const uint8_t *,
    struct disklabel *, daddr_t *);
void spooffat(const uint8_t *, struct disklabel *, daddr_t *);

int gpt_chk_mbr(struct dos_partition *, uint64_t);
int gpt_get_hdr(struct buf *, void (*)(struct buf *), struct disklabel *,
    uint64_t, struct gpt_header *);
int gpt_get_parts(struct buf *, void (*)(struct buf *),
    struct disklabel *, const struct gpt_header *, struct gpt_partition **);
int gpt_get_fstype(const struct uuid *);
int mbr_get_fstype(const uint8_t);

int duid_equal(u_char *, u_char *);

/*
 * Compute checksum for disk label.
 */
u_int
dkcksum(struct disklabel *lp)
{
        u_int16_t *start, *end;
        u_int16_t sum = 0;

        start = (u_int16_t *)lp;
        end = (u_int16_t *)&lp->d_partitions[lp->d_npartitions];
        while (start < end)
                sum ^= *start++;
        return (sum);
}

int
initdisklabel(struct disklabel *lp)
{
        int i;

        /* minimal requirements for archetypal disk label */
        if (lp->d_secsize < DEV_BSIZE)
                lp->d_secsize = DEV_BSIZE;
        if (DL_GETDSIZE(lp) == 0)
                DL_SETDSIZE(lp, MAXDISKSIZE);
        if (lp->d_secpercyl == 0)
                return (ERANGE);
        lp->d_npartitions = MAXPARTITIONS;
        for (i = 0; i < RAW_PART; i++) {
                DL_SETPSIZE(&lp->d_partitions[i], 0);
                DL_SETPOFFSET(&lp->d_partitions[i], 0);
        }
        if (DL_GETPSIZE(&lp->d_partitions[RAW_PART]) == 0)
                DL_SETPSIZE(&lp->d_partitions[RAW_PART], DL_GETDSIZE(lp));
        DL_SETPOFFSET(&lp->d_partitions[RAW_PART], 0);
        DL_SETBSTART(lp, 0);
        DL_SETBEND(lp, DL_GETDSIZE(lp));
        lp->d_version = 1;
        return (0);
}

/*
 * Check an incoming block to make sure it is a disklabel, convert it to
 * a newer version if needed, etc etc.
 */
int
checkdisklabel(dev_t dev, void *rlp, struct disklabel *lp, u_int64_t boundstart,
    u_int64_t boundend)
{
        struct disklabel *dlp = rlp;
        struct partition *pp;
        u_int64_t disksize;
        int error = 0;
        int i;

        if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC)
                error = ENOENT; /* no disk label */
        else if (dlp->d_npartitions > MAXPARTITIONS)
                error = E2BIG;  /* too many partitions */
        else if (dlp->d_secpercyl == 0)
                error = EINVAL; /* invalid label */
        else if (dlp->d_secsize == 0)
                error = ENOSPC; /* disk too small */
        else if (dkcksum(dlp) != 0)
                error = EINVAL; /* incorrect checksum */
        else if (dlp->d_version == 0)
                error = EINVAL; /* version too old to understand */

        if (error) {
                u_int16_t *start, *end, sum = 0;

                /* If it is byte-swapped, attempt to convert it */
                if (swap32(dlp->d_magic) != DISKMAGIC ||
                    swap32(dlp->d_magic2) != DISKMAGIC ||
                    swap16(dlp->d_npartitions) > MAXPARTITIONS)
                        return (error);

                /*
                 * Need a byte-swap aware dkcksum variant
                 * inlined, because dkcksum uses a sub-field
                 */
                start = (u_int16_t *)dlp;
                end = (u_int16_t *)&dlp->d_partitions[
                    swap16(dlp->d_npartitions)];
                while (start < end)
                        sum ^= *start++;
                if (sum != 0)
                        return (error);

                dlp->d_magic = swap32(dlp->d_magic);
                dlp->d_type = swap16(dlp->d_type);

                /* d_typename and d_packname are strings */

                dlp->d_secsize = swap32(dlp->d_secsize);
                dlp->d_nsectors = swap32(dlp->d_nsectors);
                dlp->d_ntracks = swap32(dlp->d_ntracks);
                dlp->d_ncylinders = swap32(dlp->d_ncylinders);
                dlp->d_secpercyl = swap32(dlp->d_secpercyl);
                dlp->d_secperunit = swap32(dlp->d_secperunit);

                /* d_uid is a string */

                dlp->d_acylinders = swap32(dlp->d_acylinders);

                dlp->d_flags = swap32(dlp->d_flags);

                dlp->d_secperunith = swap16(dlp->d_secperunith);
                dlp->d_version = swap16(dlp->d_version);

                for (i = 0; i < NSPARE; i++)
                        dlp->d_spare[i] = swap32(dlp->d_spare[i]);

                dlp->d_magic2 = swap32(dlp->d_magic2);

                dlp->d_npartitions = swap16(dlp->d_npartitions);

                for (i = 0; i < MAXPARTITIONS; i++) {
                        pp = &dlp->d_partitions[i];
                        pp->p_size = swap32(pp->p_size);
                        pp->p_offset = swap32(pp->p_offset);
                        pp->p_offseth = swap16(pp->p_offseth);
                        pp->p_sizeh = swap16(pp->p_sizeh);
                        pp->p_cpg = swap16(pp->p_cpg);
                }

                dlp->d_checksum = 0;
                dlp->d_checksum = dkcksum(dlp);
                error = 0;
        }

        /* XXX should verify lots of other fields and whine a lot */

        /* Initial passed in lp contains the real disk size. */
        disksize = DL_GETDSIZE(lp);

        if (lp != dlp)
                *lp = *dlp;

#ifdef DEBUG
        if (DL_GETDSIZE(lp) != disksize)
                printf("on-disk disklabel has incorrect disksize (%llu)\n",
                    DL_GETDSIZE(lp));
        if (DL_GETPSIZE(&lp->d_partitions[RAW_PART]) != disksize)
                printf("on-disk disklabel RAW_PART has incorrect size (%llu)\n",
                    DL_GETPSIZE(&lp->d_partitions[RAW_PART]));
        if (DL_GETPOFFSET(&lp->d_partitions[RAW_PART]) != 0)
                printf("on-disk disklabel RAW_PART offset != 0 (%llu)\n",
                    DL_GETPOFFSET(&lp->d_partitions[RAW_PART]));
#endif
        DL_SETDSIZE(lp, disksize);
        DL_SETPSIZE(&lp->d_partitions[RAW_PART], disksize);
        DL_SETPOFFSET(&lp->d_partitions[RAW_PART], 0);
        DL_SETBSTART(lp, boundstart);
        DL_SETBEND(lp, boundend < DL_GETDSIZE(lp) ? boundend : DL_GETDSIZE(lp));

        lp->d_checksum = 0;
        lp->d_checksum = dkcksum(lp);
        return (0);
}

/*
 * Read a disk sector.
 */
int
readdisksector(struct buf *bp, void (*strat)(struct buf *),
    struct disklabel *lp, u_int64_t sector)
{
        bp->b_blkno = DL_SECTOBLK(lp, sector);
        bp->b_bcount = lp->d_secsize;
        bp->b_error = 0;
        CLR(bp->b_flags, B_READ | B_WRITE | B_DONE | B_ERROR);
        SET(bp->b_flags, B_BUSY | B_READ | B_RAW);

        (*strat)(bp);

        return (biowait(bp));
}

int
readdoslabel(struct buf *bp, void (*strat)(struct buf *), struct disklabel *lp,
    daddr_t *partoffp, int spoofonly)
{
        uint8_t                  dosbb[DEV_BSIZE];
        struct disklabel        *nlp, *rlp;
        daddr_t                  partoff;
        int                      error;

#ifdef DEBUG
        char                     devname[32];
        const char              *blkname;

        blkname = findblkname(major(bp->b_dev));
        if (blkname == NULL)
                 blkname = findblkname(major(chrtoblk(bp->b_dev)));
        if (blkname == NULL)
                snprintf(devname, sizeof(devname), "<%d, %d>", major(bp->b_dev),
                    minor(bp->b_dev));
        else
                snprintf(devname, sizeof(devname), "%s%d", blkname,
                    DISKUNIT(bp->b_dev));

        printf("readdoslabel enter: %s, spoofonly %d, partoffp %sNULL\n",
            devname, spoofonly, (partoffp == NULL) ? "" : "not ");
#endif /* DEBUG */

        error = readdisksector(bp, strat, lp, DOSBBSECTOR);
        if (error) {
                DPRINTF("readdoslabel return: %s, %d -- lp unchanged, "
                    "DOSBBSECTOR read error\n", devname, error);
                return error;
        }
        memcpy(dosbb, bp->b_data, sizeof(dosbb));

        nlp = malloc(sizeof(*nlp), M_DEVBUF, M_WAITOK);
        *nlp = *lp;
        memset(nlp->d_partitions, 0, sizeof(nlp->d_partitions));
        nlp->d_partitions[RAW_PART] = lp->d_partitions[RAW_PART];
        nlp->d_magic = 0;

        error = spoofgpt(bp, strat, dosbb, nlp, &partoff);
        if (error) {
                free(nlp, M_DEVBUF, sizeof(*nlp));
                return error;
        }
        if (nlp->d_magic != DISKMAGIC)
                spoofmbr(bp, strat, dosbb, nlp, &partoff);
        if (nlp->d_magic != DISKMAGIC)
                spooffat(dosbb, nlp, &partoff);
        if (nlp->d_magic != DISKMAGIC) {
                DPRINTF("readdoslabel: N/A -- label partition @ "
                    "daddr_t 0 (default)\n");
                partoff = 0;
        }

        if (partoffp != NULL) {
                /*
                 * If a non-zero value is returned writedisklabel() exits with
                 * EIO. If 0 is returned the label sector is read from disk and
                 * lp is copied into it. So leave lp alone!
                 */
                if (partoff == -1) {
                        DPRINTF("readdoslabel return: %s, ENXIO, lp "
                            "unchanged, *partoffp unchanged\n", devname);
                        free(nlp, M_DEVBUF, sizeof(*nlp));
                        return ENXIO;
                }
                *partoffp = partoff;
                DPRINTF("readdoslabel return: %s, 0, lp unchanged, "
                    "*partoffp set to %lld\n", devname, *partoffp);
                free(nlp, M_DEVBUF, sizeof(*nlp));
                return 0;
        }

        nlp->d_magic = lp->d_magic;
        *lp = *nlp;
        free(nlp, M_DEVBUF, sizeof(*nlp));

        lp->d_checksum = 0;
        lp->d_checksum = dkcksum(lp);

        if (spoofonly || partoff == -1) {
                DPRINTF("readdoslabel return: %s, 0, lp spoofed\n",
                    devname);
                return 0;
        }

        partoff += DOS_LABELSECTOR;
        error = readdisksector(bp, strat, lp, DL_BLKTOSEC(lp, partoff));
        if (error) {
                DPRINTF("readdoslabel return: %s, %d, lp read failed\n",
                    devname, error);
                return bp->b_error;
        }

        rlp = (struct disklabel *)(bp->b_data + DL_BLKOFFSET(lp, partoff));
        error = checkdisklabel(bp->b_dev, rlp, lp, DL_GETBSTART(rlp),
            DL_GETBEND(rlp));

        DPRINTF("readdoslabel return: %s, %d, checkdisklabel() of daddr_t "
            "%lld %s\n", devname, error, partoff, error ? "failed" : "ok");

        return error;
}

/*
 * Return the index into dp[] of the EFI GPT (0xEE) partition, or -1 if no such
 * partition exists.
 *
 * Copied into sbin/fdisk/mbr.c.
 */
int
gpt_chk_mbr(struct dos_partition *dp, uint64_t dsize)
{
        struct dos_partition *dp2;
        int efi, eficnt, found, i;
        uint32_t psize;

        found = efi = eficnt = 0;
        for (dp2 = dp, i = 0; i < NDOSPART; i++, dp2++) {
                if (dp2->dp_typ == DOSPTYP_UNUSED)
                        continue;
                found++;
                if (dp2->dp_typ != DOSPTYP_EFI)
                        continue;
                if (letoh32(dp2->dp_start) != GPTSECTOR)
                        continue;
                psize = letoh32(dp2->dp_size);
                if (psize <= (dsize - GPTSECTOR) || psize == UINT32_MAX) {
                        efi = i;
                        eficnt++;
                }
        }
        if (found == 1 && eficnt == 1)
                return (efi);

        return (-1);
}

int
gpt_get_hdr(struct buf *bp, void (*strat)(struct buf *), struct disklabel *lp,
    uint64_t sector, struct gpt_header *gh)
{
        struct gpt_header       ngh;
        int                     error;
        uint64_t                lbaend, lbastart;
        uint32_t                csum;
        uint32_t                size, partsize;


        error = readdisksector(bp, strat, lp, sector);
        if (error)
                return error;

        memcpy(&ngh, bp->b_data, sizeof(ngh));

        size = letoh32(ngh.gh_size);
        partsize = letoh32(ngh.gh_part_size);
        lbaend = letoh64(ngh.gh_lba_end);
        lbastart = letoh64(ngh.gh_lba_start);

        csum = ngh.gh_csum;
        ngh.gh_csum = 0;
        ngh.gh_csum = htole32(crc32(0, (unsigned char *)&ngh, GPTMINHDRSIZE));

        if (letoh64(ngh.gh_sig) == GPTSIGNATURE &&
            letoh32(ngh.gh_rev) == GPTREVISION &&
            size == GPTMINHDRSIZE && lbastart <= lbaend &&
            partsize == GPTMINPARTSIZE && lp->d_secsize % partsize == 0 &&
            csum == ngh.gh_csum)
                *gh = ngh;
        else
                memset(gh, 0, sizeof(*gh));

        return 0;
}

int
gpt_get_parts(struct buf *bp, void (*strat)(struct buf *), struct disklabel *lp,
    const struct gpt_header *gh, struct gpt_partition **gp)
{
        uint8_t                 *ngp;
        int                      error, i;
        uint64_t                 bytes, partlba, sectors;
        uint32_t                 partnum, partsize, partcsum;

        partlba = letoh64(gh->gh_part_lba);
        partnum = letoh32(gh->gh_part_num);
        partsize = letoh32(gh->gh_part_size);

        sectors = ((uint64_t)partnum * partsize + lp->d_secsize - 1) /
            lp->d_secsize;

        ngp = mallocarray(sectors, lp->d_secsize, M_DEVBUF, M_NOWAIT | M_ZERO);
        if (ngp == NULL) {
                *gp = NULL;
                return ENOMEM;
        }
        bytes = sectors * lp->d_secsize;

        for (i = 0; i < sectors; i++) {
                error = readdisksector(bp, strat, lp, partlba + i);
                if (error) {
                        free(ngp, M_DEVBUF, bytes);
                        *gp = NULL;
                        return error;
                }
                memcpy(ngp + i * lp->d_secsize, bp->b_data, lp->d_secsize);
        }

        partcsum = htole32(crc32(0, ngp, partnum * partsize));
        if (partcsum != gh->gh_part_csum) {
                DPRINTF("invalid %s GPT partition array @ %llu\n",
                    (letoh64(gh->gh_lba_self) == GPTSECTOR) ? "Primary" :
                    "Secondary", partlba);
                free(ngp, M_DEVBUF, bytes);
                *gp = NULL;
        } else {
                *gp = (struct gpt_partition *)ngp;
        }

        return 0;
}

/* LE format! */
#define GPT_UUID_UNUSED \
    { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
#define GPT_UUID_MICROSOFT_BASIC_DATA \
    { 0xa2, 0xa0, 0xd0, 0xeb, 0xe5, 0xb9, 0x33, 0x44, \
      0x87, 0xc0, 0x68, 0xb6, 0xb7, 0x26, 0x99, 0xc7 }
#define GPT_UUID_CHROMEOS_ROOTFS \
    { 0x02, 0xe2, 0xb8, 0x3c, 0x7e, 0x3b, 0xdd, 0x47, \
      0x8a, 0x3c, 0x7f, 0xf2, 0xa1, 0x3c, 0xfc, 0xec }
#define GPT_UUID_LINUX_FILES \
    { 0xaf, 0x3d, 0xc6, 0x0f, 0x83, 0x84, 0x72, 0x47, \
      0x8e, 0x79, 0x3d, 0x69, 0xd8, 0x47, 0x7d, 0xe4 }
#define GPT_UUID_MAC_OS_X_HFS \
    { 0x00, 0x53, 0x46, 0x48, 0x00, 0x00, 0xaa, 0x11,\
      0xaa, 0x11, 0x00, 0x30, 0x65, 0x43, 0xec, 0xac }
#define GPT_UUID_BIOS_BOOT \
    { 0x48, 0x61, 0x68, 0x21, 0x49, 0x64, 0x6f, 0x6e, \
      0x74, 0x4e, 0x65, 0x65, 0x64, 0x45, 0x46, 0x49 }

/* XXX Temporary LE versions needed until MI GPT boot code is adjusted. */
#define GPT_LEUUID_EFI_SYSTEM \
    { 0x28, 0x73, 0x2a, 0xc1, 0x1f, 0xf8, 0xd2, 0x11, \
      0xba, 0x4b, 0x00, 0xa0, 0xc9, 0x3e, 0xc9, 0x3b }
#define GPT_LEUUID_OPENBSD \
    { 0xa0, 0xc7, 0x4c, 0x82, 0xa8, 0x36, 0xe3, 0x11, \
      0x89, 0x0a, 0x95, 0x25, 0x19, 0xad, 0x3f, 0x61 }

int
gpt_get_fstype(const struct uuid *uuid_part)
{
        unsigned int            i;
        struct partfs {
                uint8_t gptype[16];
                int fstype;
        } knownfs[] = {
                { GPT_UUID_UNUSED,              FS_UNUSED },
                { GPT_LEUUID_OPENBSD,           FS_BSDFFS },
                { GPT_UUID_MICROSOFT_BASIC_DATA,FS_MSDOS  },
                { GPT_UUID_CHROMEOS_ROOTFS,     FS_EXT2FS },
                { GPT_UUID_LINUX_FILES,         FS_EXT2FS },
                { GPT_UUID_MAC_OS_X_HFS,        FS_HFS    },
                { GPT_LEUUID_EFI_SYSTEM,        FS_MSDOS  },
                { GPT_UUID_BIOS_BOOT,           FS_BOOT   }
        };

        for (i = 0; i < nitems(knownfs); i++) {
                if (!memcmp(uuid_part, knownfs[i].gptype, sizeof(struct uuid)))
                    return knownfs[i].fstype;
        }

        return FS_OTHER;
}

int
spoofgpt(struct buf *bp, void (*strat)(struct buf *), const uint8_t *dosbb,
    struct disklabel *lp, daddr_t *partoffp)
{
        struct dos_partition     dp[NDOSPART];
        struct gpt_header        gh;
        struct gpt_partition    *gp;
        struct partition        *pp;
        uint64_t                 lbaend, lbastart, labelsec;
        uint64_t                 gpbytes, end, start;
        daddr_t                  partoff;
        unsigned int             i, n;
        int                      error, fstype, obsdfound;
        uint32_t                 partnum;
        uint16_t                 sig;

        gp = NULL;
        gpbytes = 0;

        memcpy(dp, dosbb + DOSPARTOFF, sizeof(dp));
        memcpy(&sig, dosbb + DOSMBR_SIGNATURE_OFF, sizeof(sig));

        if (letoh16(sig) != DOSMBR_SIGNATURE ||
            gpt_chk_mbr(dp, DL_GETDSIZE(lp)) == -1)
                return 0;

        error = gpt_get_hdr(bp, strat, lp, GPTSECTOR, &gh);
        if (error == 0 && letoh64(gh.gh_sig) == GPTSIGNATURE)
                error = gpt_get_parts(bp, strat, lp, &gh, &gp);

        if (error || letoh64(gh.gh_sig) != GPTSIGNATURE || gp == NULL) {
                error = gpt_get_hdr(bp, strat, lp, DL_GETDSIZE(lp) - 1, &gh);
                if (error == 0 && letoh64(gh.gh_sig) == GPTSIGNATURE)
                        error = gpt_get_parts(bp, strat, lp, &gh, &gp);
        }

        if (error)
                return error;
        if (gp == NULL)
                return ENXIO;

        lbastart = letoh64(gh.gh_lba_start);
        lbaend = letoh64(gh.gh_lba_end);
        partnum = letoh32(gh.gh_part_num);

        n = 'i' - 'a';  /* Start spoofing at 'i', a.k.a. 8. */

        DL_SETBSTART(lp, lbastart);
        DL_SETBEND(lp, lbaend + 1);
        partoff = DL_SECTOBLK(lp, lbastart);
        obsdfound = 0;
        for (i = 0; i < partnum; i++) {
                fstype = gpt_get_fstype(&gp[i].gp_type);
                if (fstype == FS_UNUSED)
                        continue;
                if (fstype == FS_OTHER) {
                        DPRINTF("spoofgpt: Skipping partition %u "
                            "(unknown filesystem)\n", i);
                        continue;
                }

                start = letoh64(gp[i].gp_lba_start);
                if (start > lbaend || start < lbastart)
                        continue;

                end = letoh64(gp[i].gp_lba_end);
                if (start > end)
                        continue;

                if (obsdfound && fstype == FS_BSDFFS)
                        continue;

                if (fstype == FS_BSDFFS) {
                        obsdfound = 1;
                        partoff = DL_SECTOBLK(lp, start);
                        labelsec = DL_BLKTOSEC(lp, partoff + DOS_LABELSECTOR);
                        if (labelsec > ((end < lbaend) ? end : lbaend))
                                partoff = -1;
                        DL_SETBSTART(lp, start);
                        DL_SETBEND(lp, end + 1);
                        continue;
                }

                if (partoff != -1) {
                        labelsec = DL_BLKTOSEC(lp, partoff + DOS_LABELSECTOR);
                        if (labelsec >= start && labelsec <= end)
                                partoff = -1;
                }

                if (n < MAXPARTITIONS && end <= lbaend) {
                        pp = &lp->d_partitions[n];
                        n++;
                        pp->p_fstype = fstype;
                        DL_SETPOFFSET(pp, start);
                        DL_SETPSIZE(pp, end - start + 1);
                }
        }

        lp->d_magic = DISKMAGIC;
        *partoffp = partoff;
        free(gp, M_DEVBUF, gpbytes);

#ifdef DEBUG
        printf("readdoslabel: GPT -- ");
        if (partoff == -1)
                printf("no label partition\n");
        else if (obsdfound == 0)
            printf("label partition @ daddr_t %lld (free space)\n", partoff);
        else
            printf("label partition @ daddr_t %lld (A6)\n", partoff);
#endif  /* DEBUG */

        return 0;
}

int
mbr_get_fstype(const uint8_t dp_typ)
{
        switch (dp_typ) {
        case DOSPTYP_OPENBSD:
                return FS_BSDFFS;
        case DOSPTYP_UNUSED:
                return FS_UNUSED;
        case DOSPTYP_LINUX:
                return FS_EXT2FS;
        case DOSPTYP_NTFS:
                return FS_NTFS;
        case DOSPTYP_EFISYS:
        case DOSPTYP_FAT12:
        case DOSPTYP_FAT16S:
        case DOSPTYP_FAT16B:
        case DOSPTYP_FAT16L:
        case DOSPTYP_FAT32:
        case DOSPTYP_FAT32L:
                return FS_MSDOS;
        case DOSPTYP_EFI:
        case DOSPTYP_EXTEND:
        case DOSPTYP_EXTENDL:
        default:
                return FS_OTHER;
        }
}

void
spoofmbr(struct buf *bp, void (*strat)(struct buf *), const uint8_t *dosbb,
    struct disklabel *lp, daddr_t *partoffp)
{
        struct dos_partition     dp[NDOSPART];
        struct partition        *pp;
        uint64_t                 sector = DOSBBSECTOR;
        uint64_t                 start, end;
        daddr_t                  labeloff, partoff;
        unsigned int             i, n, parts;
        int                      wander = 1, ebr = 0;
        int                      error, obsdfound;
        uint32_t                 extoff = 0;
        uint16_t                 sig;
        uint8_t                  fstype;

        memcpy(&sig, dosbb + DOSMBR_SIGNATURE_OFF, sizeof(sig));
        if (letoh16(sig) != DOSMBR_SIGNATURE)
                return;
        memcpy(dp, dosbb + DOSPARTOFF, sizeof(dp));

        obsdfound = 0;
        partoff = 0;
        parts = 0;
        n = 'i' - 'a';
        while (wander && ebr < DOS_MAXEBR) {
                ebr++;
                wander = 0;
                if (sector < extoff)
                        sector = extoff;

                error = 0;
                if (sector != DOSBBSECTOR) {
                        error = readdisksector(bp, strat, lp, sector);
                        if (error)
                                break;
                        memcpy(&sig, bp->b_data + DOSMBR_SIGNATURE_OFF,
                            sizeof(sig));
                        if (letoh16(sig) != DOSMBR_SIGNATURE)
                                break;
                        memcpy(dp, bp->b_data + DOSPARTOFF, sizeof(dp));
                }

                for (i = 0; i < NDOSPART; i++) {
                        if (letoh32(dp[i].dp_size) == 0)
                                continue;
                        if (obsdfound && dp[i].dp_typ == DOSPTYP_OPENBSD)
                                continue;

                        if (dp[i].dp_typ != DOSPTYP_OPENBSD) {
                                if (letoh32(dp[i].dp_start) > DL_GETDSIZE(lp))
                                        continue;
                                if (letoh32(dp[i].dp_size) > DL_GETDSIZE(lp))
                                        continue;
                        }

                        start = sector + letoh32(dp[i].dp_start);
                        end = start + letoh32(dp[i].dp_size);

                        parts++;
                        if (obsdfound == 0) {
                                labeloff = partoff + DOS_LABELSECTOR;
                                if (labeloff >= DL_SECTOBLK(lp, start) &&
                                    labeloff < DL_SECTOBLK(lp, end))
                                        partoff = -1;
                        }

                        switch (dp[i].dp_typ) {
                        case DOSPTYP_OPENBSD:
                                obsdfound = 1;
                                partoff = DL_SECTOBLK(lp, start);
                                labeloff = partoff + DOS_LABELSECTOR;
                                if (labeloff >= DL_SECTOBLK(lp, end))
                                        partoff = -1;
                                DL_SETBSTART(lp, start);
                                DL_SETBEND(lp, end);
                                continue;
                        case DOSPTYP_EFI:
                                continue;
                        case DOSPTYP_EXTEND:
                        case DOSPTYP_EXTENDL:
                                sector = start + extoff;
                                if (extoff == 0) {
                                        extoff = start;
                                        sector = 0;
                                }
                                wander = 1;
                                continue;
                        default:
                                break;
                        }

                        fstype = mbr_get_fstype(dp[i].dp_typ);
                        if (n < MAXPARTITIONS) {
                                pp = &lp->d_partitions[n++];
                                pp->p_fstype = fstype;
                                if (start)
                                        DL_SETPOFFSET(pp, start);
                                DL_SETPSIZE(pp, end - start);
                        }
                }
        }

        if (parts > 0) {
                lp->d_magic = DISKMAGIC;
                *partoffp = partoff;
#ifdef DEBUG
        printf("readdoslabel: MBR -- ");
        if (partoff == -1)
                printf("no label partition\n");
        else if (obsdfound == 0)
            printf("label partition @ daddr_t %lld (free space)\n", partoff);
        else
            printf("label partition @ daddr_t %lld (A6)\n", partoff);
#endif  /* DEBUG */
        }
}

void
spooffat(const uint8_t *dosbb, struct disklabel *lp, daddr_t *partoffp)
{
        uint16_t                secsize;

#define VALID_JMP(_p) (((_p)[0] == 0xeb && (_p)[2] == 0x90) || (_p)[0] == 0xe9)
#define VALID_FAT(_p) ((_p)[16] == 1 || (_p)[16] == 2)
#define VALID_SEC(_s) ((_s) >= DEV_BSIZE && (_s) <= 4096 && ((_s) % 512 == 0))

        memcpy(&secsize, dosbb + 11, sizeof(secsize));
        secsize = letoh16(secsize);

        if (VALID_JMP(dosbb) && VALID_SEC(secsize) && VALID_FAT(dosbb)) {
                lp->d_partitions['i' - 'a'] = lp->d_partitions[RAW_PART];
                lp->d_partitions['i' - 'a'].p_fstype = FS_MSDOS;
                *partoffp = -1;
                lp->d_magic = DISKMAGIC;
                DPRINTF("readdoslabel: FAT -- no label partition\n");
        }
}

/*
 * Check new disk label for sensibility before setting it.
 */
int
setdisklabel(struct disklabel *olp, struct disklabel *nlp, u_int64_t openmask)
{
        struct partition *opp, *npp;
        struct disk *dk;
        int i;

        /* sanity clause */
        if (nlp->d_secpercyl == 0 || nlp->d_secsize == 0 ||
            (nlp->d_secsize % DEV_BSIZE) != 0)
                return (EINVAL);

        /* special case to allow disklabel to be invalidated */
        if (nlp->d_magic == 0xffffffff) {
                *olp = *nlp;
                return (0);
        }

        if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC ||
            dkcksum(nlp) != 0)
                return (EINVAL);

        /* XXX missing check if other dos partitions will be overwritten */

        for (i = 0; i < MAXPARTITIONS; i++) {
                opp = &olp->d_partitions[i];
                npp = &nlp->d_partitions[i];
                if ((openmask & (1ULL << i)) &&
                    (DL_GETPOFFSET(npp) != DL_GETPOFFSET(opp) ||
                    DL_GETPSIZE(npp) < DL_GETPSIZE(opp)))
                        return (EBUSY);
                /*
                 * Copy internally-set partition information
                 * if new label doesn't include it.             XXX
                 */
                if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) {
                        npp->p_fragblock = opp->p_fragblock;
                        npp->p_cpg = opp->p_cpg;
                }
        }

        /* Generate a UID if the disklabel does not already have one. */
        if (duid_iszero(nlp->d_uid)) {
                do {
                        arc4random_buf(nlp->d_uid, sizeof(nlp->d_uid));
                        TAILQ_FOREACH(dk, &disklist, dk_link)
                                if (dk->dk_label &&
                                    duid_equal(dk->dk_label->d_uid, nlp->d_uid))
                                        break;
                } while (dk != NULL || duid_iszero(nlp->d_uid));
        }

        /* Preserve the disk size and RAW_PART values. */
        DL_SETDSIZE(nlp, DL_GETDSIZE(olp));
        npp = &nlp->d_partitions[RAW_PART];
        DL_SETPOFFSET(npp, 0);
        DL_SETPSIZE(npp, DL_GETDSIZE(nlp));

        nlp->d_checksum = 0;
        nlp->d_checksum = dkcksum(nlp);
        *olp = *nlp;

        disk_change = 1;

        return (0);
}

/*
 * Determine the size of the transfer, and make sure it is within the
 * boundaries of the partition. Adjust transfer if needed, and signal errors or
 * early completion.
 */
int
bounds_check_with_label(struct buf *bp, struct disklabel *lp)
{
        struct partition *p = &lp->d_partitions[DISKPART(bp->b_dev)];
        daddr_t partblocks, sz;

        /* Avoid division by zero, negative offsets, and negative sizes. */
        if (lp->d_secpercyl == 0 || bp->b_blkno < 0 || bp->b_bcount < 0)
                goto bad;

        /* Ensure transfer is a whole number of aligned sectors. */
        if ((bp->b_blkno % DL_BLKSPERSEC(lp)) != 0 ||
            (bp->b_bcount % lp->d_secsize) != 0)
                goto bad;

        /* Ensure transfer starts within partition boundary. */
        partblocks = DL_SECTOBLK(lp, DL_GETPSIZE(p));
        if (bp->b_blkno > partblocks)
                goto bad;

        /* If exactly at end of partition or null transfer, return EOF. */
        if (bp->b_blkno == partblocks || bp->b_bcount == 0)
                goto done;

        /* Truncate request if it extends past the end of the partition. */
        sz = bp->b_bcount >> DEV_BSHIFT;
        if (sz > partblocks - bp->b_blkno) {
                sz = partblocks - bp->b_blkno;
                bp->b_bcount = sz << DEV_BSHIFT;
        }

        return (0);

 bad:
        bp->b_error = EINVAL;
        bp->b_flags |= B_ERROR;
 done:
        bp->b_resid = bp->b_bcount;
        return (-1);
}

/*
 * Disk error is the preface to plaintive error messages
 * about failing disk transfers.  It prints messages of the form

hp0g: hard error reading fsbn 12345 of 12344-12347 (hp0 bn %d cn %d tn %d sn %d)

 * if the offset of the error in the transfer and a disk label
 * are both available.  blkdone should be -1 if the position of the error
 * is unknown; the disklabel pointer may be null from drivers that have not
 * been converted to use them.  The message is printed with printf
 * if pri is LOG_PRINTF, otherwise it uses log at the specified priority.
 * The message should be completed (with at least a newline) with printf
 * or addlog, respectively.  There is no trailing space.
 */
void
diskerr(struct buf *bp, char *dname, char *what, int pri, int blkdone,
    struct disklabel *lp)
{
        int unit = DISKUNIT(bp->b_dev), part = DISKPART(bp->b_dev);
        int (*pr)(const char *, ...) __attribute__((__format__(__kprintf__,1,2)));
        char partname = DL_PARTNUM2NAME(part);
        daddr_t sn;

        if (pri != LOG_PRINTF) {
                log(pri, "%s", "");
                pr = addlog;
        } else
                pr = printf;
        (*pr)("%s%d%c: %s %sing fsbn ", dname, unit, partname, what,
            bp->b_flags & B_READ ? "read" : "writ");
        sn = bp->b_blkno;
        if (bp->b_bcount <= DEV_BSIZE)
                (*pr)("%lld", (long long)sn);
        else {
                if (blkdone >= 0) {
                        sn += blkdone;
                        (*pr)("%lld of ", (long long)sn);
                }
                (*pr)("%lld-%lld", (long long)bp->b_blkno,
                    (long long)(bp->b_blkno + (bp->b_bcount - 1) / DEV_BSIZE));
        }
        if (lp && (blkdone >= 0 || bp->b_bcount <= lp->d_secsize)) {
                sn += DL_SECTOBLK(lp, DL_GETPOFFSET(&lp->d_partitions[part]));
                (*pr)(" (%s%d bn %lld; cn %lld", dname, unit, (long long)sn,
                    (long long)(sn / DL_SECTOBLK(lp, lp->d_secpercyl)));
                sn %= DL_SECTOBLK(lp, lp->d_secpercyl);
                (*pr)(" tn %lld sn %lld)",
                    (long long)(sn / DL_SECTOBLK(lp, lp->d_nsectors)),
                    (long long)(sn % DL_SECTOBLK(lp, lp->d_nsectors)));
        }
}

/*
 * Initialize the disklist.  Called by main() before autoconfiguration.
 */
void
disk_init(void)
{

        TAILQ_INIT(&disklist);
        disk_count = disk_change = 0;
}

int
disk_construct(struct disk *diskp)
{
        rw_init_flags(&diskp->dk_lock, "dklk", RWL_IS_VNODE);
        mtx_init(&diskp->dk_mtx, IPL_BIO);

        diskp->dk_flags |= DKF_CONSTRUCTED;

        return (0);
}

/*
 * Attach a disk.
 */
void
disk_attach(struct device *dv, struct disk *diskp)
{
        int majdev;

        KERNEL_ASSERT_LOCKED();

        if (!ISSET(diskp->dk_flags, DKF_CONSTRUCTED))
                disk_construct(diskp);

        /*
         * Allocate and initialize the disklabel structures.  Note that
         * it's not safe to sleep here, since we're probably going to be
         * called during autoconfiguration.
         */
        diskp->dk_label = malloc(sizeof(struct disklabel), M_DEVBUF,
            M_NOWAIT|M_ZERO);
        if (diskp->dk_label == NULL)
                panic("disk_attach: can't allocate storage for disklabel");

        /*
         * Set the attached timestamp.
         */
        microuptime(&diskp->dk_attachtime);

        /*
         * Link into the disklist.
         */
        TAILQ_INSERT_TAIL(&disklist, diskp, dk_link);
        ++disk_count;
        disk_change = 1;

        /*
         * Store device structure and number for later use.
         */
        diskp->dk_device = dv;
        diskp->dk_devno = NODEV;
        if (dv != NULL) {
                majdev = findblkmajor(dv);
                if (majdev >= 0)
                        diskp->dk_devno =
                            MAKEDISKDEV(majdev, dv->dv_unit, RAW_PART);

                if (diskp->dk_devno != NODEV) {
                        struct disk_attach_task *dat;

                        dat = malloc(sizeof(*dat), M_TEMP, M_WAITOK);

                        /* XXX: Assumes dk is part of the device softc. */
                        device_ref(dv);
                        dat->dk = diskp;

                        task_set(&dat->task, disk_attach_callback, dat);
                        task_add(systq, &dat->task);
                }
        }

        if (softraid_disk_attach)
                softraid_disk_attach(diskp, 1);
}

void
disk_attach_callback(void *xdat)
{
        struct disk_attach_task *dat = xdat;
        struct disk *dk = dat->dk;
        struct disklabel *dl;
        char errbuf[100];

        free(dat, M_TEMP, sizeof(*dat));

        if (dk->dk_flags & (DKF_OPENED | DKF_NOLABELREAD))
                goto done;

        /* Read disklabel. */
        dl = malloc(sizeof(*dl), M_DEVBUF, M_WAITOK);
        if (disk_readlabel(dl, dk->dk_devno, errbuf, sizeof(errbuf)) == NULL)
                enqueue_randomness(dl->d_checksum);
        free(dl, M_DEVBUF, sizeof(*dl));

done:
        dk->dk_flags |= DKF_OPENED;
        device_unref(dk->dk_device);
        wakeup(dk);
}

/*
 * Detach a disk.
 */
void
disk_detach(struct disk *diskp)
{
        KERNEL_ASSERT_LOCKED();

        if (softraid_disk_attach)
                softraid_disk_attach(diskp, -1);

        /*
         * Free the space used by the disklabel structures.
         */
        free(diskp->dk_label, M_DEVBUF, sizeof(*diskp->dk_label));

        /*
         * Remove from the disklist.
         */
        TAILQ_REMOVE(&disklist, diskp, dk_link);
        disk_change = 1;
        if (--disk_count < 0)
                panic("disk_detach: disk_count < 0");
}

int
disk_openpart(struct disk *dk, int part, int fmt, int haslabel)
{
        /* Unless opening the raw partition, check that the partition exists. */
        if (part != RAW_PART && (!haslabel ||
            part >= dk->dk_label->d_npartitions ||
            dk->dk_label->d_partitions[part].p_fstype == FS_UNUSED))
                return (ENXIO);

        /* Ensure the partition doesn't get changed under our feet. */
        switch (fmt) {
        case S_IFCHR:
                dk->dk_copenmask |= (1ULL << part);
                break;
        case S_IFBLK:
                dk->dk_bopenmask |= (1ULL << part);
                break;
        }
        dk->dk_openmask = dk->dk_copenmask | dk->dk_bopenmask;

        return (0);
}

void
disk_closepart(struct disk *dk, int part, int fmt)
{
        switch (fmt) {
        case S_IFCHR:
                dk->dk_copenmask &= ~(1ULL << part);
                break;
        case S_IFBLK:
                dk->dk_bopenmask &= ~(1ULL << part);
                break;
        }
        dk->dk_openmask = dk->dk_copenmask | dk->dk_bopenmask;
}

void
disk_gone(int (*open)(dev_t, int, int, struct proc *), int unit)
{
        int bmaj, cmaj, mn;

        /* Locate the lowest minor number to be detached. */
        mn = DISKMINOR(unit, 0);

        for (bmaj = 0; bmaj < nblkdev; bmaj++)
                if (bdevsw[bmaj].d_open == open)
                        vdevgone(bmaj, mn, mn + MAXPARTITIONS - 1, VBLK);
        for (cmaj = 0; cmaj < nchrdev; cmaj++)
                if (cdevsw[cmaj].d_open == open)
                        vdevgone(cmaj, mn, mn + MAXPARTITIONS - 1, VCHR);
}

/*
 * Increment a disk's busy counter.  If the counter is going from
 * 0 to 1, set the timestamp.
 */
void
disk_busy(struct disk *diskp)
{

        /*
         * XXX We'd like to use something as accurate as microtime(),
         * but that doesn't depend on the system TOD clock.
         */
        mtx_enter(&diskp->dk_mtx);
        if (diskp->dk_busy++ == 0)
                microuptime(&diskp->dk_timestamp);
        mtx_leave(&diskp->dk_mtx);
}

/*
 * Decrement a disk's busy counter, increment the byte count, total busy
 * time, and reset the timestamp.
 */
void
disk_unbusy(struct disk *diskp, long bcount, daddr_t blkno, int read)
{
        struct timeval dv_time, diff_time;

        mtx_enter(&diskp->dk_mtx);

        if (diskp->dk_busy-- == 0)
                printf("disk_unbusy: %s: dk_busy < 0\n", diskp->dk_name);

        microuptime(&dv_time);

        timersub(&dv_time, &diskp->dk_timestamp, &diff_time);
        timeradd(&diskp->dk_time, &diff_time, &diskp->dk_time);

        diskp->dk_timestamp = dv_time;
        if (bcount > 0) {
                if (read) {
                        diskp->dk_rbytes += bcount;
                        diskp->dk_rxfer++;
                } else {
                        diskp->dk_wbytes += bcount;
                        diskp->dk_wxfer++;
                }
        } else
                diskp->dk_seek++;

        mtx_leave(&diskp->dk_mtx);

        enqueue_randomness(bcount ^ diff_time.tv_usec ^
            (blkno >> 32) ^ (blkno & 0xffffffff));
}

int
disk_lock(struct disk *dk)
{
        return (rw_enter(&dk->dk_lock, RW_WRITE|RW_INTR));
}

void
disk_lock_nointr(struct disk *dk)
{
        rw_enter_write(&dk->dk_lock);
}

void
disk_unlock(struct disk *dk)
{
        rw_exit_write(&dk->dk_lock);
}

int
dk_mountroot(void)
{
        char errbuf[100];
        int part = DISKPART(rootdev);
        int (*mountrootfn)(void);
        struct disklabel *dl;
        char *error;

        dl = malloc(sizeof(*dl), M_DEVBUF, M_WAITOK);
        error = disk_readlabel(dl, rootdev, errbuf, sizeof(errbuf));
        if (error)
                panic("%s", error);

        if (DL_GETPSIZE(&dl->d_partitions[part]) == 0)
                panic("root filesystem has size 0");
        switch (dl->d_partitions[part].p_fstype) {
#ifdef EXT2FS
        case FS_EXT2FS:
                {
                extern int ext2fs_mountroot(void);
                mountrootfn = ext2fs_mountroot;
                }
                break;
#endif
#ifdef FFS
        case FS_BSDFFS:
                {
                extern int ffs_mountroot(void);
                mountrootfn = ffs_mountroot;
                }
                break;
#endif
#ifdef CD9660
        case FS_ISO9660:
                {
                extern int cd9660_mountroot(void);
                mountrootfn = cd9660_mountroot;
                }
                break;
#endif
        default:
#ifdef FFS
                {
                extern int ffs_mountroot(void);

                printf("filesystem type %d not known.. assuming ffs\n",
                    dl->d_partitions[part].p_fstype);
                mountrootfn = ffs_mountroot;
                }
#else
                panic("disk 0x%x filesystem type %d not known",
                    rootdev, dl->d_partitions[part].p_fstype);
#endif
        }
        free(dl, M_DEVBUF, sizeof(*dl));

        return (*mountrootfn)();
}

struct device *
getdisk(char *str, int len, int defpart, dev_t *devp)
{
        struct device *dv;

        if ((dv = parsedisk(str, len, defpart, devp)) == NULL) {
                printf("use one of: exit");
                TAILQ_FOREACH(dv, &alldevs, dv_list) {
                        if (dv->dv_class == DV_DISK)
                                printf(" %s[a-p]", dv->dv_xname);
#if defined(NFSCLIENT)
                        if (dv->dv_class == DV_IFNET)
                                printf(" %s", dv->dv_xname);
#endif
                }
                printf("\n");
        }
        return (dv);
}

struct device *
parsedisk(char *str, int len, int defpart, dev_t *devp)
{
        struct device *dv;
        int majdev, part = defpart;
        char c;

        if (len == 0)
                return (NULL);
        c = str[len-1];
        part = DL_PARTNAME2NUM(c);
        if (part == -1 || part >= MAXPARTITIONS) {
                part = defpart;
        } else
                len -=1;

        TAILQ_FOREACH(dv, &alldevs, dv_list) {
                if (dv->dv_class == DV_DISK &&
                    strncmp(str, dv->dv_xname, len) == 0 &&
                    dv->dv_xname[len] == '\0') {
                        majdev = findblkmajor(dv);
                        if (majdev < 0)
                                return NULL;
                        *devp = MAKEDISKDEV(majdev, dv->dv_unit, part);
                        break;
                }
#if defined(NFSCLIENT)
                if (dv->dv_class == DV_IFNET &&
                    strncmp(str, dv->dv_xname, len) == 0 &&
                    dv->dv_xname[len] == '\0') {
                        *devp = NODEV;
                        break;
                }
#endif
        }

        return (dv);
}

void
setroot(struct device *bootdv, int part, int exitflags)
{
        int majdev, unit, len, s, slept = 0;
        dev_t *swp;
        struct device *dv;
        dev_t nrootdev, nswapdev = NODEV, temp = NODEV;
        struct ifnet *ifp = NULL;
        struct disk *dk;
        char buf[128];
#if defined(NFSCLIENT)
        extern char *nfsbootdevname;
#endif

        /* Ensure that all disk attach callbacks have completed. */
        do {
                TAILQ_FOREACH(dk, &disklist, dk_link) {
                        if (dk->dk_devno != NODEV &&
                            (dk->dk_flags & DKF_OPENED) == 0) {
                                tsleep_nsec(dk, 0, "dkopen", SEC_TO_NSEC(1));
                                slept++;
                                break;
                        }
                }
        } while (dk != NULL && slept < 5);

        if (slept == 5) {
                printf("disklabels not read:");
                TAILQ_FOREACH(dk, &disklist, dk_link)
                        if (dk->dk_devno != NODEV &&
                            (dk->dk_flags & DKF_OPENED) == 0)
                                printf(" %s", dk->dk_name);
                printf("\n");
        }

        if (duid_iszero(bootduid)) {
                /* Locate DUID for boot disk since it was not provided. */
                TAILQ_FOREACH(dk, &disklist, dk_link)
                        if (dk->dk_device == bootdv)
                                break;
                if (dk)
                        bcopy(dk->dk_label->d_uid, bootduid, sizeof(bootduid));
        } else if (bootdv == NULL) {
                /* Locate boot disk based on the provided DUID. */
                TAILQ_FOREACH(dk, &disklist, dk_link)
                        if (duid_equal(dk->dk_label->d_uid, bootduid))
                                break;
                if (dk)
                        bootdv = dk->dk_device;
        }
        bcopy(bootduid, rootduid, sizeof(rootduid));

#if NSOFTRAID > 0
        sr_map_root();
#endif

        /*
         * If `swap generic' and we couldn't determine boot device,
         * ask the user.
         */
        dk = NULL;
        if (mountroot == NULL && bootdv == NULL)
                boothowto |= RB_ASKNAME;
        if (boothowto & RB_ASKNAME) {
                while (1) {
                        printf("root device");
                        if (bootdv != NULL) {
                                printf(" (default %s", bootdv->dv_xname);
                                if (bootdv->dv_class == DV_DISK)
                                        printf("%c", DL_PARTNUM2NAME(part));
                                printf(")");
                        }
                        printf(": ");
                        s = splhigh();
                        cnpollc(1);
                        len = getsn(buf, sizeof(buf));
                        cnpollc(0);
                        splx(s);
                        if (strcmp(buf, "exit") == 0)
                                reboot(exitflags);
                        if (len == 0 && bootdv != NULL) {
                                strlcpy(buf, bootdv->dv_xname, sizeof buf);
                                //strlcat(buf, DL_PARTNUM2NAME(part), sizeof buf);
                                len = strlen(buf);
                        }
                        if (len > 0 && buf[len - 1] == '*') {
                                buf[--len] = '\0';
                                dv = getdisk(buf, len, part, &nrootdev);
                                if (dv != NULL) {
                                        rootdv = dv;
                                        nswapdev = nrootdev;
                                        goto gotswap;
                                }
                        }
                        dv = getdisk(buf, len, part, &nrootdev);
                        if (dv != NULL) {
                                rootdv = dv;
                                break;
                        }
                }

                if (rootdv->dv_class == DV_IFNET)
                        goto gotswap;

                /* try to build swap device out of new root device */
                while (1) {
                        printf("swap device");
                        if (rootdv != NULL)
                                printf(" (default %s%s)", rootdv->dv_xname,
                                    rootdv->dv_class == DV_DISK ? "b" : "");
                        printf(": ");
                        s = splhigh();
                        cnpollc(1);
                        len = getsn(buf, sizeof(buf));
                        cnpollc(0);
                        splx(s);
                        if (strcmp(buf, "exit") == 0)
                                reboot(exitflags);
                        if (len == 0 && rootdv != NULL) {
                                switch (rootdv->dv_class) {
                                case DV_IFNET:
                                        nswapdev = NODEV;
                                        break;
                                case DV_DISK:
                                        nswapdev = MAKEDISKDEV(major(nrootdev),
                                            DISKUNIT(nrootdev), 1);
                                        if (nswapdev == nrootdev)
                                                continue;
                                        break;
                                default:
                                        break;
                                }
                                break;
                        }
                        dv = getdisk(buf, len, 1, &nswapdev);
                        if (dv) {
                                if (dv->dv_class == DV_IFNET)
                                        nswapdev = NODEV;
                                if (nswapdev == nrootdev)
                                        continue;
                                break;
                        }
                }
gotswap:
                rootdev = nrootdev;
                dumpdev = nswapdev;
                swdevt[0] = nswapdev;
                swdevt[1] = NODEV;
#if defined(NFSCLIENT)
        } else if (mountroot == nfs_mountroot) {
                rootdv = bootdv;
                rootdev = dumpdev = swapdev = NODEV;
#endif
        } else if (mountroot == NULL && rootdev == NODEV) {
                /*
                 * `swap generic'
                 */
                rootdv = bootdv;

                if (bootdv->dv_class == DV_DISK) {
                        if (!duid_iszero(rootduid)) {
                                TAILQ_FOREACH(dk, &disklist, dk_link)
                                        if (dk->dk_label && duid_equal(
                                            dk->dk_label->d_uid, rootduid))
                                                break;
                                if (dk == NULL)
                                        panic("root device (%s) not found",
                                            duid_format(rootduid));
                                rootdv = dk->dk_device;
                        }
                }

                majdev = findblkmajor(rootdv);
                if (majdev >= 0) {
                        /*
                         * Root and swap are on the disk.
                         * Assume swap is on partition b.
                         */
                        rootdev = MAKEDISKDEV(majdev, rootdv->dv_unit, part);
                        nswapdev = MAKEDISKDEV(majdev, rootdv->dv_unit, 1);
                } else {
                        /*
                         * Root and swap are on a net.
                         */
                        nswapdev = NODEV;
                }
                dumpdev = nswapdev;
                swdevt[0] = nswapdev;
                /* swdevt[1] = NODEV; */
        } else {
                /* Completely pre-configured, but we want rootdv .. */
                majdev = major(rootdev);
                if (findblkname(majdev) == NULL)
                        return;
                unit = DISKUNIT(rootdev);
                part = DISKPART(rootdev);
                snprintf(buf, sizeof buf, "%s%d%c",
                    findblkname(majdev), unit, DL_PARTNUM2NAME(part));
                rootdv = parsedisk(buf, strlen(buf), 0, &nrootdev);
                if (rootdv == NULL)
                        panic("root device (%s) not found", buf);
        }

        if (bootdv != NULL && bootdv->dv_class == DV_IFNET)
                ifp = if_unit(bootdv->dv_xname);

        if (ifp) {
                if_addgroup(ifp, "netboot");
                if_put(ifp);
        }

        switch (rootdv->dv_class) {
#if defined(NFSCLIENT)
        case DV_IFNET:
                mountroot = nfs_mountroot;
                nfsbootdevname = rootdv->dv_xname;
                return;
#endif
        case DV_DISK:
                mountroot = dk_mountroot;
                part = DISKPART(rootdev);
                break;
        default:
                printf("can't figure root, hope your kernel is right\n");
                return;
        }

        printf("root on %s%c", rootdv->dv_xname, DL_PARTNUM2NAME(part));

        if (dk && dk->dk_device == rootdv)
                printf(" (%s.%c)", duid_format(rootduid), DL_PARTNUM2NAME(part));

        /*
         * Make the swap partition on the root drive the primary swap.
         */
        for (swp = swdevt; *swp != NODEV; swp++) {
                if (major(rootdev) == major(*swp) &&
                    DISKUNIT(rootdev) == DISKUNIT(*swp)) {
                        temp = swdevt[0];
                        swdevt[0] = *swp;
                        *swp = temp;
                        break;
                }
        }
        if (*swp != NODEV) {
                /*
                 * If dumpdev was the same as the old primary swap device,
                 * move it to the new primary swap device.
                 */
                if (temp == dumpdev)
                        dumpdev = swdevt[0];
        }
        if (swdevt[0] != NODEV)
                printf(" swap on %s%d%c", findblkname(major(swdevt[0])),
                    DISKUNIT(swdevt[0]), DL_PARTNUM2NAME(DISKPART(swdevt[0])));
        if (dumpdev != NODEV)
                printf(" dump on %s%d%c", findblkname(major(dumpdev)),
                    DISKUNIT(dumpdev), DL_PARTNUM2NAME(DISKPART(dumpdev)));
        printf("\n");
}

extern const struct nam2blk nam2blk[];

int
findblkmajor(struct device *dv)
{
        char buf[16], *p;
        int i;

        if (strlcpy(buf, dv->dv_xname, sizeof buf) >= sizeof buf)
                return (-1);
        for (p = buf; *p; p++)
                if (*p >= '0' && *p <= '9')
                        *p = '\0';

        for (i = 0; nam2blk[i].name; i++)
                if (!strcmp(buf, nam2blk[i].name))
                        return (nam2blk[i].maj);
        return (-1);
}

char *
findblkname(int maj)
{
        int i;

        for (i = 0; nam2blk[i].name; i++)
                if (nam2blk[i].maj == maj)
                        return (nam2blk[i].name);
        return (NULL);
}

char *
disk_readlabel(struct disklabel *dl, dev_t dev, char *errbuf, size_t errsize)
{
        struct vnode *vn;
        dev_t chrdev, rawdev;
        int error;

        chrdev = blktochr(dev);
        rawdev = MAKEDISKDEV(major(chrdev), DISKUNIT(chrdev), RAW_PART);

#ifdef DEBUG
        printf("dev=0x%x chrdev=0x%x rawdev=0x%x\n", dev, chrdev, rawdev);
#endif

        if (cdevvp(rawdev, &vn)) {
                snprintf(errbuf, errsize,
                    "cannot obtain vnode for 0x%x/0x%x", dev, rawdev);
                return (errbuf);
        }

        error = VOP_OPEN(vn, FREAD, NOCRED, curproc);
        if (error) {
                snprintf(errbuf, errsize,
                    "cannot open disk, 0x%x/0x%x, error %d",
                    dev, rawdev, error);
                goto done;
        }

        error = VOP_IOCTL(vn, DIOCGDINFO, (caddr_t)dl, FREAD, NOCRED, curproc);
        if (error) {
                snprintf(errbuf, errsize,
                    "cannot read disk label, 0x%x/0x%x, error %d",
                    dev, rawdev, error);
        }
done:
        VOP_CLOSE(vn, FREAD, NOCRED, curproc);
        vput(vn);
        if (error)
                return (errbuf);
        return (NULL);
}

int
disk_map(const char *path, char *mappath, int size, int flags)
{
        struct disk *dk, *mdk;
        u_char uid[8];
        char c, part;
        int i, partno;

        /*
         * Attempt to map a request for a disklabel UID to the correct device.
         * We should be supplied with a disklabel UID which has the following
         * format:
         *
         * [disklabel uid] . [partition]
         *
         * Alternatively, if the DM_OPENPART flag is set the disklabel UID can
         * based passed on its own.
         */

        if (strchr(path, '/') != NULL)
                return -1;

        /* Verify that the device name is properly formed. */
        if (!((strlen(path) == 16 && (flags & DM_OPENPART)) ||
            (strlen(path) == 18 && path[16] == '.')))
                return -1;

        /* Get partition. */
        if (flags & DM_OPENPART) {
                partno = RAW_PART;
                part = DL_PARTNUM2NAME(partno);
        } else {
                part = path[17];
                partno = DL_PARTNAME2NUM(part);
        }
        if (partno == -1)
                return -1;

        /* Derive label UID. */
        memset(uid, 0, sizeof(uid));
        for (i = 0; i < 16; i++) {
                c = path[i];
                if (c >= '0' && c <= '9')
                        c -= '0';
                else if (c >= 'a' && c <= 'f')
                        c -= ('a' - 10);
                else
                        return -1;

                uid[i / 2] <<= 4;
                uid[i / 2] |= c & 0xf;
        }

        mdk = NULL;
        TAILQ_FOREACH(dk, &disklist, dk_link) {
                if (dk->dk_label && memcmp(dk->dk_label->d_uid, uid,
                    sizeof(dk->dk_label->d_uid)) == 0) {
                        /* Fail if there are duplicate UIDs! */
                        if (mdk != NULL)
                                return -1;
                        mdk = dk;
                }
        }

        if (mdk == NULL || mdk->dk_name == NULL)
                return -1;

        snprintf(mappath, size, "/dev/%s%s%c",
            (flags & DM_OPENBLCK) ? "" : "r", mdk->dk_name, part);

        return 0;
}

/*
 * Lookup a disk device and verify that it has completed attaching.
 */
struct device *
disk_lookup(struct cfdriver *cd, int unit)
{
        struct device *dv;
        struct disk *dk;

        dv = device_lookup(cd, unit);
        if (dv == NULL)
                return (NULL);

        TAILQ_FOREACH(dk, &disklist, dk_link)
                if (dk->dk_device == dv)
                        break;

        if (dk == NULL) {
                device_unref(dv);
                return (NULL);
        }

        return (dv);
}

int
duid_equal(u_char *duid1, u_char *duid2)
{
        return (memcmp(duid1, duid2, DUID_SIZE) == 0);
}

int
duid_iszero(u_char *duid)
{
        u_char zeroduid[DUID_SIZE];

        memset(zeroduid, 0, sizeof(zeroduid));

        return (duid_equal(duid, zeroduid));
}

const char *
duid_format(u_char *duid)
{
        static char duid_str[17];

        KERNEL_ASSERT_LOCKED();

        snprintf(duid_str, sizeof(duid_str),
            "%02x%02x%02x%02x%02x%02x%02x%02x",
            duid[0], duid[1], duid[2], duid[3],
            duid[4], duid[5], duid[6], duid[7]);

        return (duid_str);
}