/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2011 Alexander Motin <mav@FreeBSD.org>
 * Copyright (c) 2000 - 2008 Søren Schmidt <sos@FreeBSD.org>
 * 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 AUTHORS 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 AUTHORS 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/param.h>
#include <sys/bio.h>
#include <sys/endian.h>
#include <sys/kernel.h>
#include <sys/kobj.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/systm.h>
#include <sys/taskqueue.h>
#include <geom/geom.h>
#include <geom/geom_dbg.h>
#include "geom/raid/g_raid.h"
#include "g_raid_md_if.h"

static MALLOC_DEFINE(M_MD_SII, "md_sii_data", "GEOM_RAID SiI metadata");

struct sii_raid_conf {
        uint16_t        ata_params_00_53[54];
        uint64_t        total_sectors;          /* 54 - 57 */
        uint16_t        ata_params_58_81[72];
        uint16_t        product_id;             /* 130 */
        uint16_t        vendor_id;              /* 131 */
        uint16_t        version_minor;          /* 132 */
        uint16_t        version_major;          /* 133 */
        uint8_t         timestamp[6];           /* 134 - 136 */
        uint16_t        strip_sectors;          /* 137 */
        uint16_t        dummy_2;
        uint8_t         disk_number;            /* 139 */
        uint8_t         type;
#define SII_T_RAID0             0x00
#define SII_T_RAID1             0x01
#define SII_T_RAID01            0x02
#define SII_T_SPARE             0x03
#define SII_T_CONCAT            0x04
#define SII_T_RAID5             0x10
#define SII_T_RESERVED          0xfd
#define SII_T_JBOD              0xff

        uint8_t         raid0_disks;            /* 140 */
        uint8_t         raid0_ident;
        uint8_t         raid1_disks;            /* 141 */
        uint8_t         raid1_ident;
        uint64_t        rebuild_lba;            /* 142 - 145 */
        uint32_t        generation;             /* 146 - 147 */
        uint8_t         disk_status;            /* 148 */
#define SII_S_CURRENT           0x01
#define SII_S_REBUILD           0x02
#define SII_S_DROPPED           0x03
#define SII_S_REMOVED           0x04

        uint8_t         raid_status;
#define SII_S_ONLINE            0x01
#define SII_S_AVAILABLE         0x02

        uint8_t         raid_location;          /* 149 */
        uint8_t         disk_location;
        uint8_t         auto_rebuild;           /* 150 */
#define SII_R_REBUILD           0x00
#define SII_R_NOREBUILD         0xff

        uint8_t         dummy_3;
        uint8_t         name[16];               /* 151 - 158 */
        uint16_t        checksum;               /* 159 */
        uint16_t        ata_params_160_255[96];
} __packed;

struct g_raid_md_sii_perdisk {
        struct sii_raid_conf    *pd_meta;
        int                      pd_disk_pos;
        off_t                    pd_disk_size;
};

struct g_raid_md_sii_object {
        struct g_raid_md_object  mdio_base;
        uint8_t                  mdio_timestamp[6];
        uint8_t                  mdio_location;
        uint32_t                 mdio_generation;
        struct sii_raid_conf    *mdio_meta;
        struct callout           mdio_start_co; /* STARTING state timer. */
        int                      mdio_total_disks;
        int                      mdio_disks_present;
        int                      mdio_started;
        int                      mdio_incomplete;
        struct root_hold_token  *mdio_rootmount; /* Root mount delay token. */
};

static g_raid_md_create_t g_raid_md_create_sii;
static g_raid_md_taste_t g_raid_md_taste_sii;
static g_raid_md_event_t g_raid_md_event_sii;
static g_raid_md_ctl_t g_raid_md_ctl_sii;
static g_raid_md_write_t g_raid_md_write_sii;
static g_raid_md_fail_disk_t g_raid_md_fail_disk_sii;
static g_raid_md_free_disk_t g_raid_md_free_disk_sii;
static g_raid_md_free_t g_raid_md_free_sii;

static kobj_method_t g_raid_md_sii_methods[] = {
        KOBJMETHOD(g_raid_md_create,    g_raid_md_create_sii),
        KOBJMETHOD(g_raid_md_taste,     g_raid_md_taste_sii),
        KOBJMETHOD(g_raid_md_event,     g_raid_md_event_sii),
        KOBJMETHOD(g_raid_md_ctl,       g_raid_md_ctl_sii),
        KOBJMETHOD(g_raid_md_write,     g_raid_md_write_sii),
        KOBJMETHOD(g_raid_md_fail_disk, g_raid_md_fail_disk_sii),
        KOBJMETHOD(g_raid_md_free_disk, g_raid_md_free_disk_sii),
        KOBJMETHOD(g_raid_md_free,      g_raid_md_free_sii),
        { 0, 0 }
};

static struct g_raid_md_class g_raid_md_sii_class = {
        "SiI",
        g_raid_md_sii_methods,
        sizeof(struct g_raid_md_sii_object),
        .mdc_enable = 1,
        .mdc_priority = 100
};

static void
g_raid_md_sii_print(struct sii_raid_conf *meta)
{

        if (g_raid_debug < 1)
                return;

        printf("********* ATA SiI RAID Metadata *********\n");
        printf("total_sectors       %llu\n",
            (long long unsigned)meta->total_sectors);
        printf("product_id          0x%04x\n", meta->product_id);
        printf("vendor_id           0x%04x\n", meta->vendor_id);
        printf("version_minor       0x%04x\n", meta->version_minor);
        printf("version_major       0x%04x\n", meta->version_major);
        printf("timestamp           0x%02x%02x%02x%02x%02x%02x\n",
            meta->timestamp[5], meta->timestamp[4], meta->timestamp[3],
            meta->timestamp[2], meta->timestamp[1], meta->timestamp[0]);
        printf("strip_sectors       %d\n", meta->strip_sectors);
        printf("disk_number         %d\n", meta->disk_number);
        printf("type                0x%02x\n", meta->type);
        printf("raid0_disks         %d\n", meta->raid0_disks);
        printf("raid0_ident         %d\n", meta->raid0_ident);
        printf("raid1_disks         %d\n", meta->raid1_disks);
        printf("raid1_ident         %d\n", meta->raid1_ident);
        printf("rebuild_lba         %llu\n",
            (long long unsigned)meta->rebuild_lba);
        printf("generation          %d\n", meta->generation);
        printf("disk_status         %d\n", meta->disk_status);
        printf("raid_status         %d\n", meta->raid_status);
        printf("raid_location       %d\n", meta->raid_location);
        printf("disk_location       %d\n", meta->disk_location);
        printf("auto_rebuild        %d\n", meta->auto_rebuild);
        printf("name                <%.16s>\n", meta->name);
        printf("checksum            0x%04x\n", meta->checksum);
        printf("=================================================\n");
}

static struct sii_raid_conf *
sii_meta_copy(struct sii_raid_conf *meta)
{
        struct sii_raid_conf *nmeta;

        nmeta = malloc(sizeof(*meta), M_MD_SII, M_WAITOK);
        memcpy(nmeta, meta, sizeof(*meta));
        return (nmeta);
}

static int
sii_meta_total_disks(struct sii_raid_conf *meta)
{

        switch (meta->type) {
        case SII_T_RAID0:
        case SII_T_RAID5:
        case SII_T_CONCAT:
                return (meta->raid0_disks);
        case SII_T_RAID1:
                return (meta->raid1_disks);
        case SII_T_RAID01:
                return (meta->raid0_disks * meta->raid1_disks);
        case SII_T_SPARE:
        case SII_T_JBOD:
                return (1);
        }
        return (0);
}

static int
sii_meta_disk_pos(struct sii_raid_conf *meta, struct sii_raid_conf *pdmeta)
{

        if (pdmeta->type == SII_T_SPARE)
                return (-3);

        if (memcmp(&meta->timestamp, &pdmeta->timestamp, 6) != 0)
                return (-1);

        switch (pdmeta->type) {
        case SII_T_RAID0:
        case SII_T_RAID1:
        case SII_T_RAID5:
        case SII_T_CONCAT:
                return (pdmeta->disk_number);
        case SII_T_RAID01:
                return (pdmeta->raid1_ident * pdmeta->raid1_disks +
                    pdmeta->raid0_ident);
        case SII_T_JBOD:
                return (0);
        }
        return (-1);
}

static void
sii_meta_get_name(struct sii_raid_conf *meta, char *buf)
{
        int i;

        strncpy(buf, meta->name, 16);
        buf[16] = 0;
        for (i = 15; i >= 0; i--) {
                if (buf[i] > 0x20)
                        break;
                buf[i] = 0;
        }
}

static void
sii_meta_put_name(struct sii_raid_conf *meta, char *buf)
{

        memset(meta->name, 0x20, 16);
        memcpy(meta->name, buf, MIN(strlen(buf), 16));
}

static struct sii_raid_conf *
sii_meta_read(struct g_consumer *cp)
{
        struct g_provider *pp;
        struct sii_raid_conf *meta;
        char *buf;
        int error, i;
        uint16_t checksum, *ptr;

        pp = cp->provider;
        if (pp->sectorsize < sizeof(*meta))
                return (NULL);
        /* Read the anchor sector. */
        buf = g_read_data(cp,
            pp->mediasize - pp->sectorsize, pp->sectorsize, &error);
        if (buf == NULL) {
                G_RAID_DEBUG(1, "Cannot read metadata from %s (error=%d).",
                    pp->name, error);
                return (NULL);
        }
        meta = (struct sii_raid_conf *)buf;

        /* Check vendor ID. */
        if (meta->vendor_id != 0x1095) {
                G_RAID_DEBUG(1, "SiI vendor ID check failed on %s (0x%04x)",
                    pp->name, meta->vendor_id);
                g_free(buf);
                return (NULL);
        }

        /* Check metadata major version. */
        if (meta->version_major != 2) {
                G_RAID_DEBUG(1, "SiI version check failed on %s (%d.%d)",
                    pp->name, meta->version_major, meta->version_minor);
                g_free(buf);
                return (NULL);
        }
        meta = malloc(sizeof(*meta), M_MD_SII, M_WAITOK);
        memcpy(meta, buf, min(sizeof(*meta), pp->sectorsize));
        g_free(buf);

        /* Check metadata checksum. */
        for (checksum = 0, ptr = (uint16_t *)meta, i = 0; i <= 159; i++)
                checksum += *ptr++;
        if (checksum != 0) {
                G_RAID_DEBUG(1, "SiI checksum check failed on %s", pp->name);
                free(meta, M_MD_SII);
                return (NULL);
        }

        /* Check raid type. */
        if (meta->type != SII_T_RAID0 && meta->type != SII_T_RAID1 &&
            meta->type != SII_T_RAID01 && meta->type != SII_T_SPARE &&
            meta->type != SII_T_RAID5 && meta->type != SII_T_CONCAT &&
            meta->type != SII_T_JBOD) {
                G_RAID_DEBUG(1, "SiI unknown RAID level on %s (0x%02x)",
                    pp->name, meta->type);
                free(meta, M_MD_SII);
                return (NULL);
        }

        return (meta);
}

static int
sii_meta_write(struct g_consumer *cp, struct sii_raid_conf *meta)
{
        struct g_provider *pp;
        char *buf;
        int error, i;
        uint16_t checksum, *ptr;

        pp = cp->provider;

        /* Recalculate checksum for case if metadata were changed. */
        meta->checksum = 0;
        for (checksum = 0, ptr = (uint16_t *)meta, i = 0; i < 159; i++)
                checksum += *ptr++;
        meta->checksum -= checksum;

        /* Create and fill buffer. */
        buf = malloc(pp->sectorsize, M_MD_SII, M_WAITOK | M_ZERO);
        memcpy(buf, meta, sizeof(*meta));

        /* Write 4 copies of metadata. */
        for (i = 0; i < 4; i++) {
                error = g_write_data(cp,
                    pp->mediasize - (pp->sectorsize * (1 + 0x200 * i)),
                    buf, pp->sectorsize);
                if (error != 0) {
                        G_RAID_DEBUG(1, "Cannot write metadata to %s (error=%d).",
                            pp->name, error);
                        break;
                }
        }

        free(buf, M_MD_SII);
        return (error);
}

static int
sii_meta_erase(struct g_consumer *cp)
{
        struct g_provider *pp;
        char *buf;
        int error, i;

        pp = cp->provider;
        buf = malloc(pp->sectorsize, M_MD_SII, M_WAITOK | M_ZERO);
        /* Write 4 copies of metadata. */
        for (i = 0; i < 4; i++) {
                error = g_write_data(cp,
                    pp->mediasize - (pp->sectorsize * (1 + 0x200 * i)),
                    buf, pp->sectorsize);
                if (error != 0) {
                        G_RAID_DEBUG(1, "Cannot erase metadata on %s (error=%d).",
                            pp->name, error);
                }
        }
        free(buf, M_MD_SII);
        return (error);
}

static int
sii_meta_write_spare(struct g_consumer *cp)
{
        struct sii_raid_conf *meta;
        int error;

        meta = malloc(sizeof(*meta), M_MD_SII, M_WAITOK | M_ZERO);
        meta->total_sectors = cp->provider->mediasize /
            cp->provider->sectorsize - 0x800;
        meta->vendor_id = 0x1095;
        meta->version_minor = 0;
        meta->version_major = 2;
        meta->timestamp[0] = arc4random();
        meta->timestamp[1] = arc4random();
        meta->timestamp[2] = arc4random();
        meta->timestamp[3] = arc4random();
        meta->timestamp[4] = arc4random();
        meta->timestamp[5] = arc4random();
        meta->type = SII_T_SPARE;
        meta->generation = 1;
        meta->raid1_ident = 0xff;
        meta->raid_location = arc4random();
        error = sii_meta_write(cp, meta);
        free(meta, M_MD_SII);
        return (error);
}

static struct g_raid_disk *
g_raid_md_sii_get_disk(struct g_raid_softc *sc, int id)
{
        struct g_raid_disk      *disk;
        struct g_raid_md_sii_perdisk *pd;

        TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;
                if (pd->pd_disk_pos == id)
                        break;
        }
        return (disk);
}

static int
g_raid_md_sii_supported(int level, int qual, int disks, int force)
{

        if (disks > 8)
                return (0);
        switch (level) {
        case G_RAID_VOLUME_RL_RAID0:
                if (disks < 1)
                        return (0);
                if (!force && (disks < 2 || disks > 6))
                        return (0);
                break;
        case G_RAID_VOLUME_RL_RAID1:
                if (disks < 1)
                        return (0);
                if (!force && (disks != 2))
                        return (0);
                break;
        case G_RAID_VOLUME_RL_RAID1E:
                if (disks < 2)
                        return (0);
                if (disks % 2 != 0)
                        return (0);
                if (!force && (disks < 4))
                        return (0);
                break;
        case G_RAID_VOLUME_RL_SINGLE:
                if (disks != 1)
                        return (0);
                break;
        case G_RAID_VOLUME_RL_CONCAT:
                if (disks < 2)
                        return (0);
                break;
        case G_RAID_VOLUME_RL_RAID5:
                if (disks < 3)
                        return (0);
                if (qual != G_RAID_VOLUME_RLQ_R5LS)
                        return (0);
                break;
        default:
                return (0);
        }
        if (level != G_RAID_VOLUME_RL_RAID5 && qual != G_RAID_VOLUME_RLQ_NONE)
                return (0);
        return (1);
}

static int
g_raid_md_sii_start_disk(struct g_raid_disk *disk)
{
        struct g_raid_softc *sc;
        struct g_raid_subdisk *sd, *tmpsd;
        struct g_raid_disk *olddisk, *tmpdisk;
        struct g_raid_md_object *md;
        struct g_raid_md_sii_object *mdi;
        struct g_raid_md_sii_perdisk *pd, *oldpd;
        struct sii_raid_conf *meta;
        int disk_pos, resurrection = 0;

        sc = disk->d_softc;
        md = sc->sc_md;
        mdi = (struct g_raid_md_sii_object *)md;
        meta = mdi->mdio_meta;
        pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;
        olddisk = NULL;

        /* Find disk position in metadata by its serial. */
        if (pd->pd_meta != NULL)
                disk_pos = sii_meta_disk_pos(meta, pd->pd_meta);
        else
                disk_pos = -3;
        if (disk_pos < 0) {
                G_RAID_DEBUG1(1, sc, "Unknown, probably new or stale disk");
                /* If we are in the start process, that's all for now. */
                if (!mdi->mdio_started)
                        goto nofit;
                /*
                 * If we have already started - try to get use of the disk.
                 * Try to replace OFFLINE disks first, then FAILED.
                 */
                TAILQ_FOREACH(tmpdisk, &sc->sc_disks, d_next) {
                        if (tmpdisk->d_state != G_RAID_DISK_S_OFFLINE &&
                            tmpdisk->d_state != G_RAID_DISK_S_FAILED)
                                continue;
                        /* Make sure this disk is big enough. */
                        TAILQ_FOREACH(sd, &tmpdisk->d_subdisks, sd_next) {
                                if (sd->sd_offset + sd->sd_size + 512 >
                                    pd->pd_disk_size) {
                                        G_RAID_DEBUG1(1, sc,
                                            "Disk too small (%ju < %ju)",
                                            pd->pd_disk_size,
                                            sd->sd_offset + sd->sd_size + 512);
                                        break;
                                }
                        }
                        if (sd != NULL)
                                continue;
                        if (tmpdisk->d_state == G_RAID_DISK_S_OFFLINE) {
                                olddisk = tmpdisk;
                                break;
                        } else if (olddisk == NULL)
                                olddisk = tmpdisk;
                }
                if (olddisk == NULL) {
nofit:
                        if (disk_pos == -3 || pd->pd_disk_pos == -3) {
                                g_raid_change_disk_state(disk,
                                    G_RAID_DISK_S_SPARE);
                                return (1);
                        } else {
                                g_raid_change_disk_state(disk,
                                    G_RAID_DISK_S_STALE);
                                return (0);
                        }
                }
                oldpd = (struct g_raid_md_sii_perdisk *)olddisk->d_md_data;
                disk_pos = oldpd->pd_disk_pos;
                resurrection = 1;
        }

        if (olddisk == NULL) {
                /* Find placeholder by position. */
                olddisk = g_raid_md_sii_get_disk(sc, disk_pos);
                if (olddisk == NULL)
                        panic("No disk at position %d!", disk_pos);
                if (olddisk->d_state != G_RAID_DISK_S_OFFLINE) {
                        G_RAID_DEBUG1(1, sc, "More than one disk for pos %d",
                            disk_pos);
                        g_raid_change_disk_state(disk, G_RAID_DISK_S_STALE);
                        return (0);
                }
                oldpd = (struct g_raid_md_sii_perdisk *)olddisk->d_md_data;
        }

        /* Replace failed disk or placeholder with new disk. */
        TAILQ_FOREACH_SAFE(sd, &olddisk->d_subdisks, sd_next, tmpsd) {
                TAILQ_REMOVE(&olddisk->d_subdisks, sd, sd_next);
                TAILQ_INSERT_TAIL(&disk->d_subdisks, sd, sd_next);
                sd->sd_disk = disk;
        }
        oldpd->pd_disk_pos = -2;
        pd->pd_disk_pos = disk_pos;

        /* If it was placeholder -- destroy it. */
        if (olddisk->d_state == G_RAID_DISK_S_OFFLINE) {
                g_raid_destroy_disk(olddisk);
        } else {
                /* Otherwise, make it STALE_FAILED. */
                g_raid_change_disk_state(olddisk, G_RAID_DISK_S_STALE_FAILED);
        }

        /* Welcome the new disk. */
        if (resurrection)
                g_raid_change_disk_state(disk, G_RAID_DISK_S_ACTIVE);
        else if (pd->pd_meta->disk_status == SII_S_CURRENT ||
            pd->pd_meta->disk_status == SII_S_REBUILD)
                g_raid_change_disk_state(disk, G_RAID_DISK_S_ACTIVE);
        else
                g_raid_change_disk_state(disk, G_RAID_DISK_S_FAILED);
        TAILQ_FOREACH(sd, &disk->d_subdisks, sd_next) {
                /*
                 * Different disks may have different sizes,
                 * in concat mode. Update from real disk size.
                 */
                if (meta->type == SII_T_CONCAT || meta->type == SII_T_JBOD)
                        sd->sd_size = pd->pd_disk_size - 0x800 * 512;

                if (resurrection) {
                        /* New or ex-spare disk. */
                        g_raid_change_subdisk_state(sd,
                            G_RAID_SUBDISK_S_NEW);
                } else if (pd->pd_meta->disk_status == SII_S_REBUILD) {
                        /* Rebuilding disk. */
                        g_raid_change_subdisk_state(sd,
                            G_RAID_SUBDISK_S_REBUILD);
                        if (pd->pd_meta->generation == meta->generation)
                                sd->sd_rebuild_pos = pd->pd_meta->rebuild_lba * 512;
                        else
                                sd->sd_rebuild_pos = 0;
                } else if (pd->pd_meta->disk_status == SII_S_CURRENT) {
                        if (pd->pd_meta->raid_status == SII_S_ONLINE ||
                            pd->pd_meta->generation != meta->generation) {
                                /* Dirty or resyncing disk. */
                                g_raid_change_subdisk_state(sd,
                                    G_RAID_SUBDISK_S_STALE);
                        } else {
                                /* Up to date disk. */
                                g_raid_change_subdisk_state(sd,
                                    G_RAID_SUBDISK_S_ACTIVE);
                        }
                } else {
                        g_raid_change_subdisk_state(sd,
                            G_RAID_SUBDISK_S_FAILED);
                }
                g_raid_event_send(sd, G_RAID_SUBDISK_E_NEW,
                    G_RAID_EVENT_SUBDISK);
        }

        /* Update status of our need for spare. */
        if (mdi->mdio_started) {
                mdi->mdio_incomplete =
                    (g_raid_ndisks(sc, G_RAID_DISK_S_ACTIVE) <
                     mdi->mdio_total_disks);
        }

        return (resurrection);
}

static void
g_disk_md_sii_retaste(void *arg, int pending)
{

        G_RAID_DEBUG(1, "Array is not complete, trying to retaste.");
        g_retaste(&g_raid_class);
        free(arg, M_MD_SII);
}

static void
g_raid_md_sii_refill(struct g_raid_softc *sc)
{
        struct g_raid_md_object *md;
        struct g_raid_md_sii_object *mdi;
        struct g_raid_disk *disk;
        struct task *task;
        int update, na;

        md = sc->sc_md;
        mdi = (struct g_raid_md_sii_object *)md;
        update = 0;
        do {
                /* Make sure we miss anything. */
                na = g_raid_ndisks(sc, G_RAID_DISK_S_ACTIVE);
                if (na == mdi->mdio_total_disks)
                        break;

                G_RAID_DEBUG1(1, md->mdo_softc,
                    "Array is not complete (%d of %d), "
                    "trying to refill.", na, mdi->mdio_total_disks);

                /* Try to get use some of STALE disks. */
                TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                        if (disk->d_state == G_RAID_DISK_S_STALE) {
                                update += g_raid_md_sii_start_disk(disk);
                                if (disk->d_state == G_RAID_DISK_S_ACTIVE)
                                        break;
                        }
                }
                if (disk != NULL)
                        continue;

                /* Try to get use some of SPARE disks. */
                TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                        if (disk->d_state == G_RAID_DISK_S_SPARE) {
                                update += g_raid_md_sii_start_disk(disk);
                                if (disk->d_state == G_RAID_DISK_S_ACTIVE)
                                        break;
                        }
                }
        } while (disk != NULL);

        /* Write new metadata if we changed something. */
        if (update)
                g_raid_md_write_sii(md, NULL, NULL, NULL);

        /* Update status of our need for spare. */
        mdi->mdio_incomplete = (g_raid_ndisks(sc, G_RAID_DISK_S_ACTIVE) <
            mdi->mdio_total_disks);

        /* Request retaste hoping to find spare. */
        if (mdi->mdio_incomplete) {
                task = malloc(sizeof(struct task),
                    M_MD_SII, M_WAITOK | M_ZERO);
                TASK_INIT(task, 0, g_disk_md_sii_retaste, task);
                taskqueue_enqueue(taskqueue_swi, task);
        }
}

static void
g_raid_md_sii_start(struct g_raid_softc *sc)
{
        struct g_raid_md_object *md;
        struct g_raid_md_sii_object *mdi;
        struct g_raid_md_sii_perdisk *pd;
        struct sii_raid_conf *meta;
        struct g_raid_volume *vol;
        struct g_raid_subdisk *sd;
        struct g_raid_disk *disk, *best;
        off_t size;
        int j, disk_pos;
        uint32_t gendiff, bestgendiff;
        char buf[17];

        md = sc->sc_md;
        mdi = (struct g_raid_md_sii_object *)md;
        meta = mdi->mdio_meta;

        /* Create volumes and subdisks. */
        sii_meta_get_name(meta, buf);
        vol = g_raid_create_volume(sc, buf, -1);
        vol->v_mediasize = (off_t)meta->total_sectors * 512;
        vol->v_raid_level_qualifier = G_RAID_VOLUME_RLQ_NONE;
        if (meta->type == SII_T_RAID0) {
                vol->v_raid_level = G_RAID_VOLUME_RL_RAID0;
                size = vol->v_mediasize / mdi->mdio_total_disks;
        } else if (meta->type == SII_T_RAID1) {
                vol->v_raid_level = G_RAID_VOLUME_RL_RAID1;
                size = vol->v_mediasize;
        } else if (meta->type == SII_T_RAID01) {
                vol->v_raid_level = G_RAID_VOLUME_RL_RAID1E;
                size = vol->v_mediasize / (mdi->mdio_total_disks / 2);
        } else if (meta->type == SII_T_CONCAT) {
                if (mdi->mdio_total_disks == 1)
                        vol->v_raid_level = G_RAID_VOLUME_RL_SINGLE;
                else
                        vol->v_raid_level = G_RAID_VOLUME_RL_CONCAT;
                size = 0;
        } else if (meta->type == SII_T_RAID5) {
                vol->v_raid_level = G_RAID_VOLUME_RL_RAID5;
                vol->v_raid_level_qualifier = G_RAID_VOLUME_RLQ_R5LS;
                size = vol->v_mediasize / (mdi->mdio_total_disks - 1);
        } else if (meta->type == SII_T_JBOD) {
                vol->v_raid_level = G_RAID_VOLUME_RL_SINGLE;
                size = 0;
        } else {
                vol->v_raid_level = G_RAID_VOLUME_RL_UNKNOWN;
                size = 0;
        }
        vol->v_strip_size = meta->strip_sectors * 512; //ZZZ
        vol->v_disks_count = mdi->mdio_total_disks;
        vol->v_sectorsize = 512; //ZZZ
        for (j = 0; j < vol->v_disks_count; j++) {
                sd = &vol->v_subdisks[j];
                sd->sd_offset = 0;
                sd->sd_size = size;
        }
        g_raid_start_volume(vol);

        /* Create disk placeholders to store data for later writing. */
        for (disk_pos = 0; disk_pos < mdi->mdio_total_disks; disk_pos++) {
                pd = malloc(sizeof(*pd), M_MD_SII, M_WAITOK | M_ZERO);
                pd->pd_disk_pos = disk_pos;
                disk = g_raid_create_disk(sc);
                disk->d_md_data = (void *)pd;
                disk->d_state = G_RAID_DISK_S_OFFLINE;
                sd = &vol->v_subdisks[disk_pos];
                sd->sd_disk = disk;
                TAILQ_INSERT_TAIL(&disk->d_subdisks, sd, sd_next);
        }

        /*
         * Make all disks found till the moment take their places
         * in order of their generation numbers.
         */
        do {
                best = NULL;
                bestgendiff = 0xffffffff;
                TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                        if (disk->d_state != G_RAID_DISK_S_NONE)
                                continue;
                        pd = disk->d_md_data;
                        if (pd->pd_meta == NULL)
                                gendiff = 0xfffffffe;
                        else
                                gendiff = meta->generation -
                                    pd->pd_meta->generation;
                        if (gendiff < bestgendiff) {
                                best = disk;
                                bestgendiff = gendiff;
                        }
                }
                if (best != NULL)
                        g_raid_md_sii_start_disk(best);
        } while (best != NULL);

        mdi->mdio_started = 1;
        G_RAID_DEBUG1(0, sc, "Array started.");
        g_raid_md_write_sii(md, NULL, NULL, NULL);

        /* Pickup any STALE/SPARE disks to refill array if needed. */
        g_raid_md_sii_refill(sc);

        g_raid_event_send(vol, G_RAID_VOLUME_E_START, G_RAID_EVENT_VOLUME);

        callout_stop(&mdi->mdio_start_co);
        G_RAID_DEBUG1(1, sc, "root_mount_rel %p", mdi->mdio_rootmount);
        root_mount_rel(mdi->mdio_rootmount);
        mdi->mdio_rootmount = NULL;
}

static void
g_raid_md_sii_new_disk(struct g_raid_disk *disk)
{
        struct g_raid_softc *sc;
        struct g_raid_md_object *md;
        struct g_raid_md_sii_object *mdi;
        struct sii_raid_conf *pdmeta;
        struct g_raid_md_sii_perdisk *pd;

        sc = disk->d_softc;
        md = sc->sc_md;
        mdi = (struct g_raid_md_sii_object *)md;
        pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;
        pdmeta = pd->pd_meta;

        if (mdi->mdio_started) {
                if (g_raid_md_sii_start_disk(disk))
                        g_raid_md_write_sii(md, NULL, NULL, NULL);
        } else {
                if (mdi->mdio_meta == NULL ||
                    ((int32_t)(pdmeta->generation - mdi->mdio_generation)) > 0) {
                        G_RAID_DEBUG1(1, sc, "Newer disk");
                        if (mdi->mdio_meta != NULL)
                                free(mdi->mdio_meta, M_MD_SII);
                        mdi->mdio_meta = sii_meta_copy(pdmeta);
                        mdi->mdio_generation = mdi->mdio_meta->generation;
                        mdi->mdio_total_disks = sii_meta_total_disks(pdmeta);
                        mdi->mdio_disks_present = 1;
                } else if (pdmeta->generation == mdi->mdio_generation) {
                        mdi->mdio_disks_present++;
                        G_RAID_DEBUG1(1, sc, "Matching disk (%d of %d up)",
                            mdi->mdio_disks_present,
                            mdi->mdio_total_disks);
                } else {
                        G_RAID_DEBUG1(1, sc, "Older disk");
                }

                /* If we collected all needed disks - start array. */
                if (mdi->mdio_disks_present == mdi->mdio_total_disks)
                        g_raid_md_sii_start(sc);
        }
}

static void
g_raid_sii_go(void *arg)
{
        struct g_raid_softc *sc;
        struct g_raid_md_object *md;
        struct g_raid_md_sii_object *mdi;

        sc = arg;
        md = sc->sc_md;
        mdi = (struct g_raid_md_sii_object *)md;
        if (!mdi->mdio_started) {
                G_RAID_DEBUG1(0, sc, "Force array start due to timeout.");
                g_raid_event_send(sc, G_RAID_NODE_E_START, 0);
        }
}

static int
g_raid_md_create_sii(struct g_raid_md_object *md, struct g_class *mp,
    struct g_geom **gp)
{
        struct g_raid_softc *sc;
        struct g_raid_md_sii_object *mdi;
        char name[32];

        mdi = (struct g_raid_md_sii_object *)md;
        mdi->mdio_timestamp[5] = arc4random();
        mdi->mdio_timestamp[4] = arc4random();
        mdi->mdio_timestamp[3] = arc4random();
        mdi->mdio_timestamp[2] = arc4random();
        mdi->mdio_timestamp[1] = arc4random();
        mdi->mdio_timestamp[0] = arc4random();
        mdi->mdio_location = arc4random();
        mdi->mdio_generation = 0;
        snprintf(name, sizeof(name), "SiI-%02x%02x%02x%02x%02x%02x",
            mdi->mdio_timestamp[5], mdi->mdio_timestamp[4],
            mdi->mdio_timestamp[3], mdi->mdio_timestamp[2],
            mdi->mdio_timestamp[1], mdi->mdio_timestamp[0]);
        sc = g_raid_create_node(mp, name, md);
        if (sc == NULL)
                return (G_RAID_MD_TASTE_FAIL);
        md->mdo_softc = sc;
        *gp = sc->sc_geom;
        return (G_RAID_MD_TASTE_NEW);
}

static int
g_raid_md_taste_sii(struct g_raid_md_object *md, struct g_class *mp,
                              struct g_consumer *cp, struct g_geom **gp)
{
        struct g_consumer *rcp;
        struct g_provider *pp;
        struct g_raid_md_sii_object *mdi, *mdi1;
        struct g_raid_softc *sc;
        struct g_raid_disk *disk;
        struct sii_raid_conf *meta;
        struct g_raid_md_sii_perdisk *pd;
        struct g_geom *geom;
        int disk_pos, result, spare, len;
        char name[32];
        uint16_t vendor;

        G_RAID_DEBUG(1, "Tasting SiI on %s", cp->provider->name);
        mdi = (struct g_raid_md_sii_object *)md;
        pp = cp->provider;

        /* Explicitly reject providers with too small sector size */
        if (pp->sectorsize < sizeof(struct sii_raid_conf)) {
                G_RAID_DEBUG(1, "SiI sector size too small on %s: %u < %zu",
                    pp->name, pp->sectorsize, sizeof(struct sii_raid_conf));
                return (G_RAID_MD_TASTE_FAIL);
        }

        /* Read metadata from device. */
        meta = NULL;
        g_topology_unlock();
        vendor = 0xffff;
        len = sizeof(vendor);
        if (pp->geom->rank == 1)
                g_io_getattr("GEOM::hba_vendor", cp, &len, &vendor);
        meta = sii_meta_read(cp);
        g_topology_lock();
        if (meta == NULL) {
                if (g_raid_aggressive_spare) {
                        if (vendor == 0x1095) {
                                G_RAID_DEBUG(1,
                                    "No SiI metadata, forcing spare.");
                                spare = 2;
                                goto search;
                        } else {
                                G_RAID_DEBUG(1,
                                    "SiI vendor mismatch 0x%04x != 0x1095",
                                    vendor);
                        }
                }
                return (G_RAID_MD_TASTE_FAIL);
        }

        /* Check this disk position in obtained metadata. */
        disk_pos = sii_meta_disk_pos(meta, meta);
        if (disk_pos == -1) {
                G_RAID_DEBUG(1, "SiI disk position not found");
                goto fail1;
        }

        /* Metadata valid. Print it. */
        g_raid_md_sii_print(meta);
        G_RAID_DEBUG(1, "SiI disk position %d", disk_pos);
        spare = (meta->type == SII_T_SPARE) ? 1 : 0;

search:
        /* Search for matching node. */
        sc = NULL;
        mdi1 = NULL;
        LIST_FOREACH(geom, &mp->geom, geom) {
                sc = geom->softc;
                if (sc == NULL)
                        continue;
                if (sc->sc_stopping != 0)
                        continue;
                if (sc->sc_md->mdo_class != md->mdo_class)
                        continue;
                mdi1 = (struct g_raid_md_sii_object *)sc->sc_md;
                if (spare) {
                        if (mdi1->mdio_incomplete)
                                break;
                } else {
                        if (mdi1->mdio_location == meta->raid_location &&
                            memcmp(&mdi1->mdio_timestamp,
                             &meta->timestamp, 6) == 0)
                                break;
                }
        }

        /* Found matching node. */
        if (geom != NULL) {
                G_RAID_DEBUG(1, "Found matching array %s", sc->sc_name);
                result = G_RAID_MD_TASTE_EXISTING;

        } else if (spare) { /* Not found needy node -- left for later. */
                G_RAID_DEBUG(1, "Spare is not needed at this time");
                goto fail1;

        } else { /* Not found matching node -- create one. */
                result = G_RAID_MD_TASTE_NEW;
                memcpy(&mdi->mdio_timestamp, &meta->timestamp, 6);
                mdi->mdio_location = meta->raid_location;
                snprintf(name, sizeof(name), "SiI-%02x%02x%02x%02x%02x%02x",
                    mdi->mdio_timestamp[5], mdi->mdio_timestamp[4],
                    mdi->mdio_timestamp[3], mdi->mdio_timestamp[2],
                    mdi->mdio_timestamp[1], mdi->mdio_timestamp[0]);
                sc = g_raid_create_node(mp, name, md);
                md->mdo_softc = sc;
                geom = sc->sc_geom;
                callout_init(&mdi->mdio_start_co, 1);
                callout_reset(&mdi->mdio_start_co, g_raid_start_timeout * hz,
                    g_raid_sii_go, sc);
                mdi->mdio_rootmount = root_mount_hold("GRAID-SiI");
                G_RAID_DEBUG1(1, sc, "root_mount_hold %p", mdi->mdio_rootmount);
        }

        /* There is no return after this point, so we close passed consumer. */
        g_access(cp, -1, 0, 0);

        rcp = g_new_consumer(geom);
        rcp->flags |= G_CF_DIRECT_RECEIVE;
        g_attach(rcp, pp);
        if (g_access(rcp, 1, 1, 1) != 0)
                ; //goto fail1;

        g_topology_unlock();
        sx_xlock(&sc->sc_lock);

        pd = malloc(sizeof(*pd), M_MD_SII, M_WAITOK | M_ZERO);
        pd->pd_meta = meta;
        if (spare == 2) {
                pd->pd_disk_pos = -3;
        } else {
                pd->pd_disk_pos = -1;
        }
        pd->pd_disk_size = pp->mediasize;
        disk = g_raid_create_disk(sc);
        disk->d_md_data = (void *)pd;
        disk->d_consumer = rcp;
        rcp->private = disk;

        g_raid_get_disk_info(disk);

        g_raid_md_sii_new_disk(disk);

        sx_xunlock(&sc->sc_lock);
        g_topology_lock();
        *gp = geom;
        return (result);
fail1:
        free(meta, M_MD_SII);
        return (G_RAID_MD_TASTE_FAIL);
}

static int
g_raid_md_event_sii(struct g_raid_md_object *md,
    struct g_raid_disk *disk, u_int event)
{
        struct g_raid_softc *sc;
        struct g_raid_subdisk *sd;
        struct g_raid_md_sii_object *mdi;
        struct g_raid_md_sii_perdisk *pd;

        sc = md->mdo_softc;
        mdi = (struct g_raid_md_sii_object *)md;
        if (disk == NULL) {
                switch (event) {
                case G_RAID_NODE_E_START:
                        if (!mdi->mdio_started)
                                g_raid_md_sii_start(sc);
                        return (0);
                }
                return (-1);
        }
        pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;
        switch (event) {
        case G_RAID_DISK_E_DISCONNECTED:
                /* If disk was assigned, just update statuses. */
                if (pd->pd_disk_pos >= 0) {
                        g_raid_change_disk_state(disk, G_RAID_DISK_S_OFFLINE);
                        if (disk->d_consumer) {
                                g_raid_kill_consumer(sc, disk->d_consumer);
                                disk->d_consumer = NULL;
                        }
                        TAILQ_FOREACH(sd, &disk->d_subdisks, sd_next) {
                                g_raid_change_subdisk_state(sd,
                                    G_RAID_SUBDISK_S_NONE);
                                g_raid_event_send(sd, G_RAID_SUBDISK_E_DISCONNECTED,
                                    G_RAID_EVENT_SUBDISK);
                        }
                } else {
                        /* Otherwise -- delete. */
                        g_raid_change_disk_state(disk, G_RAID_DISK_S_NONE);
                        g_raid_destroy_disk(disk);
                }

                /* Write updated metadata to all disks. */
                g_raid_md_write_sii(md, NULL, NULL, NULL);

                /* Check if anything left except placeholders. */
                if (g_raid_ndisks(sc, -1) ==
                    g_raid_ndisks(sc, G_RAID_DISK_S_OFFLINE))
                        g_raid_destroy_node(sc, 0);
                else
                        g_raid_md_sii_refill(sc);
                return (0);
        }
        return (-2);
}

static int
g_raid_md_ctl_sii(struct g_raid_md_object *md,
    struct gctl_req *req)
{
        struct g_raid_softc *sc;
        struct g_raid_volume *vol;
        struct g_raid_subdisk *sd;
        struct g_raid_disk *disk;
        struct g_raid_md_sii_object *mdi;
        struct g_raid_md_sii_perdisk *pd;
        struct g_consumer *cp;
        struct g_provider *pp;
        char arg[16];
        const char *verb, *volname, *levelname, *diskname;
        int *nargs, *force;
        off_t size, sectorsize, strip;
        intmax_t *sizearg, *striparg;
        int numdisks, i, len, level, qual, update;
        int error;

        sc = md->mdo_softc;
        mdi = (struct g_raid_md_sii_object *)md;
        verb = gctl_get_param(req, "verb", NULL);
        nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
        error = 0;
        if (strcmp(verb, "label") == 0) {
                if (*nargs < 4) {
                        gctl_error(req, "Invalid number of arguments.");
                        return (-1);
                }
                volname = gctl_get_asciiparam(req, "arg1");
                if (volname == NULL) {
                        gctl_error(req, "No volume name.");
                        return (-2);
                }
                levelname = gctl_get_asciiparam(req, "arg2");
                if (levelname == NULL) {
                        gctl_error(req, "No RAID level.");
                        return (-3);
                }
                if (strcasecmp(levelname, "RAID5") == 0)
                        levelname = "RAID5-LS";
                if (g_raid_volume_str2level(levelname, &level, &qual)) {
                        gctl_error(req, "Unknown RAID level '%s'.", levelname);
                        return (-4);
                }
                numdisks = *nargs - 3;
                force = gctl_get_paraml(req, "force", sizeof(*force));
                if (!g_raid_md_sii_supported(level, qual, numdisks,
                    force ? *force : 0)) {
                        gctl_error(req, "Unsupported RAID level "
                            "(0x%02x/0x%02x), or number of disks (%d).",
                            level, qual, numdisks);
                        return (-5);
                }

                /* Search for disks, connect them and probe. */
                size = 0x7fffffffffffffffllu;
                sectorsize = 0;
                for (i = 0; i < numdisks; i++) {
                        snprintf(arg, sizeof(arg), "arg%d", i + 3);
                        diskname = gctl_get_asciiparam(req, arg);
                        if (diskname == NULL) {
                                gctl_error(req, "No disk name (%s).", arg);
                                error = -6;
                                break;
                        }
                        if (strcmp(diskname, "NONE") == 0) {
                                cp = NULL;
                                pp = NULL;
                        } else {
                                g_topology_lock();
                                cp = g_raid_open_consumer(sc, diskname);
                                if (cp == NULL) {
                                        gctl_error(req, "Can't open '%s'.",
                                            diskname);
                                        g_topology_unlock();
                                        error = -7;
                                        break;
                                }
                                pp = cp->provider;
                        }
                        pd = malloc(sizeof(*pd), M_MD_SII, M_WAITOK | M_ZERO);
                        pd->pd_disk_pos = i;
                        disk = g_raid_create_disk(sc);
                        disk->d_md_data = (void *)pd;
                        disk->d_consumer = cp;
                        if (cp == NULL)
                                continue;
                        cp->private = disk;
                        g_topology_unlock();

                        g_raid_get_disk_info(disk);

                        pd->pd_disk_size = pp->mediasize;
                        if (size > pp->mediasize)
                                size = pp->mediasize;
                        if (sectorsize < pp->sectorsize)
                                sectorsize = pp->sectorsize;
                }
                if (error != 0)
                        return (error);

                if (sectorsize <= 0) {
                        gctl_error(req, "Can't get sector size.");
                        return (-8);
                }

                /* Reserve space for metadata. */
                size -= 0x800 * sectorsize;

                /* Handle size argument. */
                len = sizeof(*sizearg);
                sizearg = gctl_get_param(req, "size", &len);
                if (sizearg != NULL && len == sizeof(*sizearg) &&
                    *sizearg > 0) {
                        if (*sizearg > size) {
                                gctl_error(req, "Size too big %lld > %lld.",
                                    (long long)*sizearg, (long long)size);
                                return (-9);
                        }
                        size = *sizearg;
                }

                /* Handle strip argument. */
                strip = 131072;
                len = sizeof(*striparg);
                striparg = gctl_get_param(req, "strip", &len);
                if (striparg != NULL && len == sizeof(*striparg) &&
                    *striparg > 0) {
                        if (*striparg < sectorsize) {
                                gctl_error(req, "Strip size too small.");
                                return (-10);
                        }
                        if (*striparg % sectorsize != 0) {
                                gctl_error(req, "Incorrect strip size.");
                                return (-11);
                        }
                        if (strip > 65535 * sectorsize) {
                                gctl_error(req, "Strip size too big.");
                                return (-12);
                        }
                        strip = *striparg;
                }

                /* Round size down to strip or sector. */
                if (level == G_RAID_VOLUME_RL_RAID1)
                        size -= (size % sectorsize);
                else if (level == G_RAID_VOLUME_RL_RAID1E &&
                    (numdisks & 1) != 0)
                        size -= (size % (2 * strip));
                else
                        size -= (size % strip);
                if (size <= 0) {
                        gctl_error(req, "Size too small.");
                        return (-13);
                }
                if (size > 0xffffffffffffllu * sectorsize) {
                        gctl_error(req, "Size too big.");
                        return (-14);
                }

                /* We have all we need, create things: volume, ... */
                mdi->mdio_total_disks = numdisks;
                mdi->mdio_started = 1;
                vol = g_raid_create_volume(sc, volname, -1);
                vol->v_md_data = (void *)(intptr_t)0;
                vol->v_raid_level = level;
                vol->v_raid_level_qualifier = qual;
                vol->v_strip_size = strip;
                vol->v_disks_count = numdisks;
                if (level == G_RAID_VOLUME_RL_RAID0 ||
                    level == G_RAID_VOLUME_RL_CONCAT ||
                    level == G_RAID_VOLUME_RL_SINGLE)
                        vol->v_mediasize = size * numdisks;
                else if (level == G_RAID_VOLUME_RL_RAID1)
                        vol->v_mediasize = size;
                else if (level == G_RAID_VOLUME_RL_RAID5)
                        vol->v_mediasize = size * (numdisks - 1);
                else { /* RAID1E */
                        vol->v_mediasize = ((size * numdisks) / strip / 2) *
                            strip;
                }
                vol->v_sectorsize = sectorsize;
                g_raid_start_volume(vol);

                /* , and subdisks. */
                TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                        pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;
                        sd = &vol->v_subdisks[pd->pd_disk_pos];
                        sd->sd_disk = disk;
                        sd->sd_offset = 0;
                        sd->sd_size = size;
                        TAILQ_INSERT_TAIL(&disk->d_subdisks, sd, sd_next);
                        if (sd->sd_disk->d_consumer != NULL) {
                                g_raid_change_disk_state(disk,
                                    G_RAID_DISK_S_ACTIVE);
                                g_raid_change_subdisk_state(sd,
                                    G_RAID_SUBDISK_S_ACTIVE);
                                g_raid_event_send(sd, G_RAID_SUBDISK_E_NEW,
                                    G_RAID_EVENT_SUBDISK);
                        } else {
                                g_raid_change_disk_state(disk, G_RAID_DISK_S_OFFLINE);
                        }
                }

                /* Write metadata based on created entities. */
                G_RAID_DEBUG1(0, sc, "Array started.");
                g_raid_md_write_sii(md, NULL, NULL, NULL);

                /* Pickup any STALE/SPARE disks to refill array if needed. */
                g_raid_md_sii_refill(sc);

                g_raid_event_send(vol, G_RAID_VOLUME_E_START,
                    G_RAID_EVENT_VOLUME);
                return (0);
        }
        if (strcmp(verb, "delete") == 0) {
                /* Check if some volume is still open. */
                force = gctl_get_paraml(req, "force", sizeof(*force));
                if (force != NULL && *force == 0 &&
                    g_raid_nopens(sc) != 0) {
                        gctl_error(req, "Some volume is still open.");
                        return (-4);
                }

                TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                        if (disk->d_consumer)
                                sii_meta_erase(disk->d_consumer);
                }
                g_raid_destroy_node(sc, 0);
                return (0);
        }
        if (strcmp(verb, "remove") == 0 ||
            strcmp(verb, "fail") == 0) {
                if (*nargs < 2) {
                        gctl_error(req, "Invalid number of arguments.");
                        return (-1);
                }
                for (i = 1; i < *nargs; i++) {
                        snprintf(arg, sizeof(arg), "arg%d", i);
                        diskname = gctl_get_asciiparam(req, arg);
                        if (diskname == NULL) {
                                gctl_error(req, "No disk name (%s).", arg);
                                error = -2;
                                break;
                        }
                        if (strncmp(diskname, _PATH_DEV, 5) == 0)
                                diskname += 5;

                        TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                                if (disk->d_consumer != NULL && 
                                    disk->d_consumer->provider != NULL &&
                                    strcmp(disk->d_consumer->provider->name,
                                     diskname) == 0)
                                        break;
                        }
                        if (disk == NULL) {
                                gctl_error(req, "Disk '%s' not found.",
                                    diskname);
                                error = -3;
                                break;
                        }

                        if (strcmp(verb, "fail") == 0) {
                                g_raid_md_fail_disk_sii(md, NULL, disk);
                                continue;
                        }

                        pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;

                        /* Erase metadata on deleting disk. */
                        sii_meta_erase(disk->d_consumer);

                        /* If disk was assigned, just update statuses. */
                        if (pd->pd_disk_pos >= 0) {
                                g_raid_change_disk_state(disk, G_RAID_DISK_S_OFFLINE);
                                g_raid_kill_consumer(sc, disk->d_consumer);
                                disk->d_consumer = NULL;
                                TAILQ_FOREACH(sd, &disk->d_subdisks, sd_next) {
                                        g_raid_change_subdisk_state(sd,
                                            G_RAID_SUBDISK_S_NONE);
                                        g_raid_event_send(sd, G_RAID_SUBDISK_E_DISCONNECTED,
                                            G_RAID_EVENT_SUBDISK);
                                }
                        } else {
                                /* Otherwise -- delete. */
                                g_raid_change_disk_state(disk, G_RAID_DISK_S_NONE);
                                g_raid_destroy_disk(disk);
                        }
                }

                /* Write updated metadata to remaining disks. */
                g_raid_md_write_sii(md, NULL, NULL, NULL);

                /* Check if anything left except placeholders. */
                if (g_raid_ndisks(sc, -1) ==
                    g_raid_ndisks(sc, G_RAID_DISK_S_OFFLINE))
                        g_raid_destroy_node(sc, 0);
                else
                        g_raid_md_sii_refill(sc);
                return (error);
        }
        if (strcmp(verb, "insert") == 0) {
                if (*nargs < 2) {
                        gctl_error(req, "Invalid number of arguments.");
                        return (-1);
                }
                update = 0;
                for (i = 1; i < *nargs; i++) {
                        /* Get disk name. */
                        snprintf(arg, sizeof(arg), "arg%d", i);
                        diskname = gctl_get_asciiparam(req, arg);
                        if (diskname == NULL) {
                                gctl_error(req, "No disk name (%s).", arg);
                                error = -3;
                                break;
                        }

                        /* Try to find provider with specified name. */
                        g_topology_lock();
                        cp = g_raid_open_consumer(sc, diskname);
                        if (cp == NULL) {
                                gctl_error(req, "Can't open disk '%s'.",
                                    diskname);
                                g_topology_unlock();
                                error = -4;
                                break;
                        }
                        pp = cp->provider;

                        pd = malloc(sizeof(*pd), M_MD_SII, M_WAITOK | M_ZERO);
                        pd->pd_disk_pos = -3;
                        pd->pd_disk_size = pp->mediasize;

                        disk = g_raid_create_disk(sc);
                        disk->d_consumer = cp;
                        disk->d_md_data = (void *)pd;
                        cp->private = disk;
                        g_topology_unlock();

                        g_raid_get_disk_info(disk);

                        /* Welcome the "new" disk. */
                        update += g_raid_md_sii_start_disk(disk);
                        if (disk->d_state == G_RAID_DISK_S_SPARE) {
                                sii_meta_write_spare(cp);
                                g_raid_destroy_disk(disk);
                        } else if (disk->d_state != G_RAID_DISK_S_ACTIVE) {
                                gctl_error(req, "Disk '%s' doesn't fit.",
                                    diskname);
                                g_raid_destroy_disk(disk);
                                error = -8;
                                break;
                        }
                }

                /* Write new metadata if we changed something. */
                if (update)
                        g_raid_md_write_sii(md, NULL, NULL, NULL);
                return (error);
        }
        gctl_error(req, "Command '%s' is not supported.", verb);
        return (-100);
}

static int
g_raid_md_write_sii(struct g_raid_md_object *md, struct g_raid_volume *tvol,
    struct g_raid_subdisk *tsd, struct g_raid_disk *tdisk)
{
        struct g_raid_softc *sc;
        struct g_raid_volume *vol;
        struct g_raid_subdisk *sd;
        struct g_raid_disk *disk;
        struct g_raid_md_sii_object *mdi;
        struct g_raid_md_sii_perdisk *pd;
        struct sii_raid_conf *meta;
        u_int i;

        sc = md->mdo_softc;
        mdi = (struct g_raid_md_sii_object *)md;

        if (sc->sc_stopping == G_RAID_DESTROY_HARD)
                return (0);

        /* Bump generation. Newly written metadata may differ from previous. */
        mdi->mdio_generation++;

        /* There is only one volume. */
        vol = TAILQ_FIRST(&sc->sc_volumes);

        /* Fill global fields. */
        meta = malloc(sizeof(*meta), M_MD_SII, M_WAITOK | M_ZERO);
        if (mdi->mdio_meta)
                memcpy(meta, mdi->mdio_meta, sizeof(*meta));
        meta->total_sectors = vol->v_mediasize / vol->v_sectorsize;
        meta->vendor_id = 0x1095;
        meta->version_minor = 0;
        meta->version_major = 2;
        memcpy(&meta->timestamp, &mdi->mdio_timestamp, 6);
        meta->strip_sectors = vol->v_strip_size / vol->v_sectorsize;
        if (vol->v_raid_level == G_RAID_VOLUME_RL_RAID0) {
                meta->type = SII_T_RAID0;
                meta->raid0_disks = vol->v_disks_count;
                meta->raid1_disks = 0xff;
        } else if (vol->v_raid_level == G_RAID_VOLUME_RL_RAID1) {
                meta->type = SII_T_RAID1;
                meta->raid0_disks = 0xff;
                meta->raid1_disks = vol->v_disks_count;
        } else if (vol->v_raid_level == G_RAID_VOLUME_RL_RAID1E) {
                meta->type = SII_T_RAID01;
                meta->raid0_disks = vol->v_disks_count / 2;
                meta->raid1_disks = 2;
        } else if (vol->v_raid_level == G_RAID_VOLUME_RL_CONCAT ||
            vol->v_raid_level == G_RAID_VOLUME_RL_SINGLE) {
                meta->type = SII_T_JBOD;
                meta->raid0_disks = vol->v_disks_count;
                meta->raid1_disks = 0xff;
        } else {
                meta->type = SII_T_RAID5;
                meta->raid0_disks = vol->v_disks_count;
                meta->raid1_disks = 0xff;
        }
        meta->generation = mdi->mdio_generation;
        meta->raid_status = vol->v_dirty ? SII_S_ONLINE : SII_S_AVAILABLE;
        for (i = 0; i < vol->v_disks_count; i++) {
                sd = &vol->v_subdisks[i];
                if (sd->sd_state == G_RAID_SUBDISK_S_STALE ||
                    sd->sd_state == G_RAID_SUBDISK_S_RESYNC)
                        meta->raid_status = SII_S_ONLINE;
        }
        meta->raid_location = mdi->mdio_location;
        sii_meta_put_name(meta, vol->v_name);

        /* We are done. Print meta data and store them to disks. */
        if (mdi->mdio_meta != NULL)
                free(mdi->mdio_meta, M_MD_SII);
        mdi->mdio_meta = meta;
        TAILQ_FOREACH(disk, &sc->sc_disks, d_next) {
                pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;
                if (disk->d_state != G_RAID_DISK_S_ACTIVE)
                        continue;
                if (pd->pd_meta != NULL) {
                        free(pd->pd_meta, M_MD_SII);
                        pd->pd_meta = NULL;
                }
                pd->pd_meta = sii_meta_copy(meta);
                if ((sd = TAILQ_FIRST(&disk->d_subdisks)) != NULL) {
                        if (sd->sd_state < G_RAID_SUBDISK_S_NEW)
                                pd->pd_meta->disk_status = SII_S_DROPPED;
                        else if (sd->sd_state < G_RAID_SUBDISK_S_STALE) {
                                pd->pd_meta->disk_status = SII_S_REBUILD;
                                pd->pd_meta->rebuild_lba =
                                    sd->sd_rebuild_pos / vol->v_sectorsize;
                        } else
                                pd->pd_meta->disk_status = SII_S_CURRENT;
                        if (vol->v_raid_level == G_RAID_VOLUME_RL_RAID1) {
                                pd->pd_meta->disk_number = sd->sd_pos;
                                pd->pd_meta->raid0_ident = 0xff;
                                pd->pd_meta->raid1_ident = 0;
                        } else if (vol->v_raid_level == G_RAID_VOLUME_RL_RAID1E) {
                                pd->pd_meta->disk_number = sd->sd_pos / meta->raid1_disks;
                                pd->pd_meta->raid0_ident = sd->sd_pos % meta->raid1_disks;
                                pd->pd_meta->raid1_ident = sd->sd_pos / meta->raid1_disks;
                        } else {
                                pd->pd_meta->disk_number = sd->sd_pos;
                                pd->pd_meta->raid0_ident = 0;
                                pd->pd_meta->raid1_ident = 0xff;
                        }
                }
                G_RAID_DEBUG(1, "Writing SiI metadata to %s",
                    g_raid_get_diskname(disk));
                g_raid_md_sii_print(pd->pd_meta);
                sii_meta_write(disk->d_consumer, pd->pd_meta);
        }
        return (0);
}

static int
g_raid_md_fail_disk_sii(struct g_raid_md_object *md,
    struct g_raid_subdisk *tsd, struct g_raid_disk *tdisk)
{
        struct g_raid_softc *sc;
        struct g_raid_md_sii_perdisk *pd;
        struct g_raid_subdisk *sd;

        sc = md->mdo_softc;
        pd = (struct g_raid_md_sii_perdisk *)tdisk->d_md_data;

        /* We can't fail disk that is not a part of array now. */
        if (pd->pd_disk_pos < 0)
                return (-1);

        /*
         * Mark disk as failed in metadata and try to write that metadata
         * to the disk itself to prevent it's later resurrection as STALE.
         */
        if (tdisk->d_consumer) {
                if (pd->pd_meta) {
                        pd->pd_meta->disk_status = SII_S_REMOVED;
                        sii_meta_write(tdisk->d_consumer, pd->pd_meta);
                } else
                        sii_meta_erase(tdisk->d_consumer);
        }

        /* Change states. */
        g_raid_change_disk_state(tdisk, G_RAID_DISK_S_FAILED);
        TAILQ_FOREACH(sd, &tdisk->d_subdisks, sd_next) {
                g_raid_change_subdisk_state(sd,
                    G_RAID_SUBDISK_S_FAILED);
                g_raid_event_send(sd, G_RAID_SUBDISK_E_FAILED,
                    G_RAID_EVENT_SUBDISK);
        }

        /* Write updated metadata to remaining disks. */
        g_raid_md_write_sii(md, NULL, NULL, tdisk);

        /* Check if anything left except placeholders. */
        if (g_raid_ndisks(sc, -1) ==
            g_raid_ndisks(sc, G_RAID_DISK_S_OFFLINE))
                g_raid_destroy_node(sc, 0);
        else
                g_raid_md_sii_refill(sc);
        return (0);
}

static int
g_raid_md_free_disk_sii(struct g_raid_md_object *md,
    struct g_raid_disk *disk)
{
        struct g_raid_md_sii_perdisk *pd;

        pd = (struct g_raid_md_sii_perdisk *)disk->d_md_data;
        if (pd->pd_meta != NULL) {
                free(pd->pd_meta, M_MD_SII);
                pd->pd_meta = NULL;
        }
        free(pd, M_MD_SII);
        disk->d_md_data = NULL;
        return (0);
}

static int
g_raid_md_free_sii(struct g_raid_md_object *md)
{
        struct g_raid_md_sii_object *mdi;

        mdi = (struct g_raid_md_sii_object *)md;
        if (!mdi->mdio_started) {
                mdi->mdio_started = 0;
                callout_stop(&mdi->mdio_start_co);
                G_RAID_DEBUG1(1, md->mdo_softc,
                    "root_mount_rel %p", mdi->mdio_rootmount);
                root_mount_rel(mdi->mdio_rootmount);
                mdi->mdio_rootmount = NULL;
        }
        if (mdi->mdio_meta != NULL) {
                free(mdi->mdio_meta, M_MD_SII);
                mdi->mdio_meta = NULL;
        }
        return (0);
}

G_RAID_MD_DECLARE(sii, "SiI");