86Box/src/disk/zip.c

/*
 * 86Box    A hypervisor and IBM PC system emulator that specializes in
 *          running old operating systems and software designed for IBM
 *          PC systems and compatibles from 1981 through fairly recent
 *          system designs based on the PCI bus.
 *
 *          This file is part of the 86Box distribution.
 *
 *          Implementation of the Iomega ZIP drive with SCSI(-like)
 *          commands, for both ATAPI and SCSI usage.
 *
 *
 *
 * Authors: Miran Grca, <mgrca8@gmail.com>
 *
 *          Copyright 2018-2019 Miran Grca.
 */
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <wchar.h>
#define HAVE_STDARG_H
#include <86box/86box.h>
#include <86box/timer.h>
#include <86box/config.h>
#include <86box/timer.h>
#include <86box/device.h>
#include <86box/scsi.h>
#include <86box/scsi_device.h>
#include <86box/nvr.h>
#include <86box/plat.h>
#include <86box/ui.h>
#include <86box/hdc.h>
#include <86box/hdc_ide.h>
#include <86box/zip.h>

#define IDE_ATAPI_IS_EARLY             id->sc->pad0

zip_drive_t zip_drives[ZIP_NUM];

/* Table of all SCSI commands and their flags, needed for the new disc change / not ready handler. */
const uint8_t zip_command_flags[0x100] = {
    IMPLEMENTED | CHECK_READY | NONDATA,          /* 0x00 */
    IMPLEMENTED | ALLOW_UA | NONDATA | SCSI_ONLY, /* 0x01 */
    0,
    IMPLEMENTED | ALLOW_UA,                                     /* 0x03 */
    IMPLEMENTED | CHECK_READY | ALLOW_UA | NONDATA | SCSI_ONLY, /* 0x04 */
    0,
    IMPLEMENTED, /* 0x06 */
    0,
    IMPLEMENTED | CHECK_READY, /* 0x08 */
    0,
    IMPLEMENTED | CHECK_READY,           /* 0x0A */
    IMPLEMENTED | CHECK_READY | NONDATA, /* 0x0B */
    IMPLEMENTED,                         /* 0x0C */
    IMPLEMENTED | ATAPI_ONLY,            /* 0x0D */
    0, 0, 0, 0,
    IMPLEMENTED | ALLOW_UA,                          /* 0x12 */
    IMPLEMENTED | CHECK_READY | NONDATA | SCSI_ONLY, /* 0x13 */
    0,
    IMPLEMENTED,             /* 0x15 */
    IMPLEMENTED | SCSI_ONLY, /* 0x16 */
    IMPLEMENTED | SCSI_ONLY, /* 0x17 */
    0, 0,
    IMPLEMENTED,               /* 0x1A */
    IMPLEMENTED | CHECK_READY, /* 0x1B */
    0,
    IMPLEMENTED,               /* 0x1D */
    IMPLEMENTED | CHECK_READY, /* 0x1E */
    0, 0, 0, 0,
    IMPLEMENTED | ATAPI_ONLY, /* 0x23 */
    0,
    IMPLEMENTED | CHECK_READY, /* 0x25 */
    0, 0,
    IMPLEMENTED | CHECK_READY, /* 0x28 */
    0,
    IMPLEMENTED | CHECK_READY,           /* 0x2A */
    IMPLEMENTED | CHECK_READY | NONDATA, /* 0x2B */
    0, 0,
    IMPLEMENTED | CHECK_READY,                       /* 0x2E */
    IMPLEMENTED | CHECK_READY | NONDATA | SCSI_ONLY, /* 0x2F */
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0,
    IMPLEMENTED | CHECK_READY, /* 0x41 */
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0,
    IMPLEMENTED, /* 0x55 */
    0, 0, 0, 0,
    IMPLEMENTED, /* 0x5A */
    0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0,
    IMPLEMENTED | CHECK_READY, /* 0xA8 */
    0,
    IMPLEMENTED | CHECK_READY, /* 0xAA */
    0, 0, 0,
    IMPLEMENTED | CHECK_READY,                       /* 0xAE */
    IMPLEMENTED | CHECK_READY | NONDATA | SCSI_ONLY, /* 0xAF */
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    IMPLEMENTED, /* 0xBD */
    0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

static uint64_t zip_mode_sense_page_flags     = (GPMODEP_R_W_ERROR_PAGE | GPMODEP_DISCONNECT_PAGE | GPMODEP_IOMEGA_PAGE | GPMODEP_ALL_PAGES);
static uint64_t zip_250_mode_sense_page_flags = (GPMODEP_R_W_ERROR_PAGE | GPMODEP_FLEXIBLE_DISK_PAGE | GPMODEP_CACHING_PAGE | GPMODEP_IOMEGA_PAGE | GPMODEP_ALL_PAGES);

static const mode_sense_pages_t zip_mode_sense_pages_default =
    // clang-format off
{   {
    {                        0,    0 },
    {    GPMODE_R_W_ERROR_PAGE, 0x0a, 0xc8, 22, 0,  0, 0, 0, 90, 0, 0x50, 0x20 },
    {   GPMODE_DISCONNECT_PAGE, 0x0e, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {       GPMODE_IOMEGA_PAGE,    0x04, 0x5c, 0x0f, 0xff, 0x0f }
}   };
// clang-format on

static const mode_sense_pages_t zip_250_mode_sense_pages_default =
    // clang-format off
{   {
    {                        0,    0 },
    {    GPMODE_R_W_ERROR_PAGE, 0x06, 0xc8, 0x64, 0,  0, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {GPMODE_FLEXIBLE_DISK_PAGE, 0x1e, 0x80, 0, 0x40, 0x20, 2, 0, 0, 0xef, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x0b, 0x7d, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {      GPMODE_CACHING_PAGE, 0x0a, 4, 0, 0xff, 0xff, 0, 0, 0xff, 0xff, 0xff, 0xff },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {       GPMODE_IOMEGA_PAGE,    0x04, 0x5c, 0x0f, 0x3c, 0x0f }
}   };
// clang-format on

static const mode_sense_pages_t zip_mode_sense_pages_default_scsi =
    // clang-format off
{   {
    {                        0,    0 },
    {    GPMODE_R_W_ERROR_PAGE, 0x0a, 0xc8, 22, 0,  0, 0, 0, 90, 0, 0x50, 0x20 },
    {   GPMODE_DISCONNECT_PAGE, 0x0e, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {       GPMODE_IOMEGA_PAGE,    0x04, 0x5c, 0x0f, 0xff, 0x0f }
}   };
// clang-format on

static const mode_sense_pages_t zip_250_mode_sense_pages_default_scsi =
    // clang-format off
{   {
    {                        0,    0 },
    {    GPMODE_R_W_ERROR_PAGE, 0x06, 0xc8, 0x64, 0,  0, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {GPMODE_FLEXIBLE_DISK_PAGE, 0x1e, 0x80, 0, 0x40, 0x20, 2, 0, 0, 0xef, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x0b, 0x7d, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {      GPMODE_CACHING_PAGE, 0x0a, 4, 0, 0xff, 0xff, 0, 0, 0xff, 0xff, 0xff, 0xff },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {       GPMODE_IOMEGA_PAGE,    0x04, 0x5c, 0x0f, 0x3c, 0x0f }
}   };
// clang-format on

static const mode_sense_pages_t zip_mode_sense_pages_changeable =
    // clang-format off
{   {
    {                        0,    0 },

    {    GPMODE_R_W_ERROR_PAGE, 0x0a, 0xFF, 0xFF, 0,  0, 0, 0, 0xFF, 0xFF, 0xFF, 0xFF },
    {   GPMODE_DISCONNECT_PAGE, 0x0e, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {       GPMODE_IOMEGA_PAGE,    0x04, 0xff, 0xff, 0xff, 0xff }
}   };
// clang-format on

static const mode_sense_pages_t zip_250_mode_sense_pages_changeable =
    // clang-format off
{   {
    {                        0,    0 },
    {    GPMODE_R_W_ERROR_PAGE, 0x06, 0xFF, 0xFF, 0,  0, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {GPMODE_FLEXIBLE_DISK_PAGE, 0x1e, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0, 0 },
    {                        0,    0 },
    {                        0,    0 },
    {      GPMODE_CACHING_PAGE, 0x0a, 4, 0, 0xff, 0xff, 0, 0, 0xff, 0xff, 0xff, 0xff },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {                        0,    0 },
    {       GPMODE_IOMEGA_PAGE,    0x04, 0xff, 0xff, 0xff, 0xff }
}   };
// clang-format on

static void zip_command_complete(zip_t *dev);
static void zip_init(zip_t *dev);

#ifdef ENABLE_ZIP_LOG
int zip_do_log = ENABLE_ZIP_LOG;

static void
zip_log(const char *fmt, ...)
{
    va_list ap;

    if (zip_do_log) {
        va_start(ap, fmt);
        pclog_ex(fmt, ap);
        va_end(ap);
    }
}
#else
#    define zip_log(fmt, ...)
#endif

int
find_zip_for_channel(uint8_t channel)
{
    for (uint8_t i = 0; i < ZIP_NUM; i++) {
        if ((zip_drives[i].bus_type == ZIP_BUS_ATAPI) && (zip_drives[i].ide_channel == channel))
            return i;
    }
    return 0xff;
}

static int
zip_load_abort(zip_t *dev)
{
    if (dev->drv->fp)
        fclose(dev->drv->fp);
    dev->drv->fp           = NULL;
    dev->drv->medium_size = 0;
    zip_eject(dev->id); /* Make sure the host OS knows we've rejected (and ejected) the image. */
    return 0;
}

int
zip_load(zip_t *dev, char *fn)
{
    int size = 0;

    if (!dev->drv) {
        zip_eject(dev->id);
        return 0;
    }

    dev->drv->fp = plat_fopen(fn, dev->drv->read_only ? "rb" : "rb+");
    if (!dev->drv->fp) {
        if (!dev->drv->read_only) {
            dev->drv->fp = plat_fopen(fn, "rb");
            if (dev->drv->fp)
                dev->drv->read_only = 1;
            else
                return zip_load_abort(dev);
        } else
            return zip_load_abort(dev);
    }

    fseek(dev->drv->fp, 0, SEEK_END);
    size = ftell(dev->drv->fp);

    if ((size == ((ZIP_250_SECTORS << 9) + 0x1000)) || (size == ((ZIP_SECTORS << 9) + 0x1000))) {
        /* This is a ZDI image. */
        size -= 0x1000;
        dev->drv->base = 0x1000;
    } else
        dev->drv->base = 0;

    if (dev->drv->is_250) {
        if ((size != (ZIP_250_SECTORS << 9)) && (size != (ZIP_SECTORS << 9))) {
            zip_log("File is incorrect size for a ZIP image\nMust be exactly %i or %i bytes\n",
                    ZIP_250_SECTORS << 9, ZIP_SECTORS << 9);
            return zip_load_abort(dev);
        }
    } else {
        if (size != (ZIP_SECTORS << 9)) {
            zip_log("File is incorrect size for a ZIP image\nMust be exactly %i bytes\n",
                    ZIP_SECTORS << 9);
            return zip_load_abort(dev);
        }
    }

    dev->drv->medium_size = size >> 9;

    if (fseek(dev->drv->fp, dev->drv->base, SEEK_SET) == -1)
        fatal("zip_load(): Error seeking to the beginning of the file\n");

    strncpy(dev->drv->image_path, fn, sizeof(dev->drv->image_path) - 1);
    // After using strncpy, dev->drv->image_path needs to be explicitly null terminated to make gcc happy.
    // In the event strlen(dev->drv->image_path) == sizeof(dev->drv->image_path) (no null terminator)
    // it is placed at the very end. Otherwise, it is placed right after the string.
    const size_t term = strlen(dev->drv->image_path) == sizeof(dev->drv->image_path) ? sizeof(dev->drv->image_path) - 1 : strlen(dev->drv->image_path);
    dev->drv->image_path[term] = '\0';

    return 1;
}

void
zip_disk_reload(zip_t *dev)
{
    int ret = 0;

    if (strlen(dev->drv->prev_image_path) == 0)
        return;
    else
        ret = zip_load(dev, dev->drv->prev_image_path);

    if (ret)
        dev->unit_attention = 1;
}

void
zip_disk_unload(zip_t *dev)
{
    if (dev->drv && dev->drv->fp) {
        fclose(dev->drv->fp);
        dev->drv->fp = NULL;
    }
}

void
zip_disk_close(zip_t *dev)
{
    if (dev->drv && dev->drv->fp) {
        zip_disk_unload(dev);

        memcpy(dev->drv->prev_image_path, dev->drv->image_path, sizeof(dev->drv->prev_image_path));
        memset(dev->drv->image_path, 0, sizeof(dev->drv->image_path));

        dev->drv->medium_size = 0;
    }
}

static void
zip_set_callback(zip_t *dev)
{
    if (dev->drv->bus_type != ZIP_BUS_SCSI)
        ide_set_callback(ide_drives[dev->drv->ide_channel], dev->callback);
}

static void
zip_init(zip_t *dev)
{
    if (dev->id >= ZIP_NUM)
        return;

    dev->requested_blocks = 1;
    dev->sense[0]         = 0xf0;
    dev->sense[7]         = 10;
    dev->drv->bus_mode    = 0;
    if (dev->drv->bus_type >= ZIP_BUS_ATAPI)
        dev->drv->bus_mode |= 2;
    if (dev->drv->bus_type < ZIP_BUS_SCSI)
        dev->drv->bus_mode |= 1;
    zip_log("ZIP %i: Bus type %i, bus mode %i\n", dev->id, dev->drv->bus_type, dev->drv->bus_mode);
    if (dev->drv->bus_type < ZIP_BUS_SCSI) {
        dev->tf->phase          = 1;
        dev->tf->request_length = 0xEB14;
    }
    dev->tf->status    = READY_STAT | DSC_STAT;
    dev->tf->pos       = 0;
    dev->packet_status = PHASE_NONE;
    zip_sense_key = zip_asc = zip_ascq = dev->unit_attention = 0;
}

static int
zip_supports_pio(zip_t *dev)
{
    return (dev->drv->bus_mode & 1);
}

static int
zip_supports_dma(zip_t *dev)
{
    return (dev->drv->bus_mode & 2);
}

/* Returns: 0 for none, 1 for PIO, 2 for DMA. */
static int
zip_current_mode(zip_t *dev)
{
    if (!zip_supports_pio(dev) && !zip_supports_dma(dev))
        return 0;
    if (zip_supports_pio(dev) && !zip_supports_dma(dev)) {
        zip_log("ZIP %i: Drive does not support DMA, setting to PIO\n", dev->id);
        return 1;
    }
    if (!zip_supports_pio(dev) && zip_supports_dma(dev))
        return 2;
    if (zip_supports_pio(dev) && zip_supports_dma(dev)) {
        zip_log("ZIP %i: Drive supports both, setting to %s\n", dev->id,
                (dev->tf->features & 1) ? "DMA" : "PIO");
        return (dev->tf->features & 1) ? 2 : 1;
    }

    return 0;
}

static void
zip_mode_sense_load(zip_t *dev)
{
    FILE *fp;
    char  fn[512];

    memset(&dev->ms_pages_saved, 0, sizeof(mode_sense_pages_t));
    if (dev->drv->is_250) {
        if (zip_drives[dev->id].bus_type == ZIP_BUS_SCSI)
            memcpy(&dev->ms_pages_saved, &zip_250_mode_sense_pages_default_scsi, sizeof(mode_sense_pages_t));
        else
            memcpy(&dev->ms_pages_saved, &zip_250_mode_sense_pages_default, sizeof(mode_sense_pages_t));
    } else {
        if (zip_drives[dev->id].bus_type == ZIP_BUS_SCSI)
            memcpy(&dev->ms_pages_saved, &zip_mode_sense_pages_default_scsi, sizeof(mode_sense_pages_t));
        else
            memcpy(&dev->ms_pages_saved, &zip_mode_sense_pages_default, sizeof(mode_sense_pages_t));
    }

    memset(fn, 0, 512);
    if (dev->drv->bus_type == ZIP_BUS_SCSI)
        sprintf(fn, "scsi_zip_%02i_mode_sense_bin", dev->id);
    else
        sprintf(fn, "zip_%02i_mode_sense_bin", dev->id);
    fp = plat_fopen(nvr_path(fn), "rb");
    if (fp) {
        /* Nothing to read, not used by ZIP. */
        fclose(fp);
    }
}

static void
zip_mode_sense_save(zip_t *dev)
{
    FILE *fp;
    char  fn[512];

    memset(fn, 0, 512);
    if (dev->drv->bus_type == ZIP_BUS_SCSI)
        sprintf(fn, "scsi_zip_%02i_mode_sense_bin", dev->id);
    else
        sprintf(fn, "zip_%02i_mode_sense_bin", dev->id);
    fp = plat_fopen(nvr_path(fn), "wb");
    if (fp) {
        /* Nothing to write, not used by ZIP. */
        fclose(fp);
    }
}

/*SCSI Mode Sense 6/10*/
static uint8_t
zip_mode_sense_read(zip_t *dev, uint8_t page_control, uint8_t page, uint8_t pos)
{
    switch (page_control) {
        case 0:
        case 3:
            if (dev->drv->is_250 && (page == 5) && (pos == 9) && (dev->drv->medium_size == ZIP_SECTORS))
                return 0x60;
            return dev->ms_pages_saved.pages[page][pos];
        case 1:
            if (dev->drv->is_250)
                return zip_250_mode_sense_pages_changeable.pages[page][pos];
            else
                return zip_mode_sense_pages_changeable.pages[page][pos];
        case 2:
            if (dev->drv->is_250) {
                if ((page == 5) && (pos == 9) && (dev->drv->medium_size == ZIP_SECTORS))
                    return 0x60;
                if (dev->drv->bus_type == ZIP_BUS_SCSI)
                    return zip_250_mode_sense_pages_default_scsi.pages[page][pos];
                else
                    return zip_250_mode_sense_pages_default.pages[page][pos];
            } else {
                if (dev->drv->bus_type == ZIP_BUS_SCSI)
                    return zip_mode_sense_pages_default_scsi.pages[page][pos];
                else
                    return zip_mode_sense_pages_default.pages[page][pos];
            }

        default:
            break;
    }

    return 0;
}

static uint32_t
zip_mode_sense(zip_t *dev, uint8_t *buf, uint32_t pos, uint8_t page, uint8_t block_descriptor_len)
{
    uint64_t pf;
    uint8_t  page_control = (page >> 6) & 3;

    if (dev->drv->is_250)
        pf = zip_250_mode_sense_page_flags;
    else
        pf = zip_mode_sense_page_flags;

    uint8_t msplen;

    page &= 0x3f;

    if (block_descriptor_len) {
        buf[pos++] = ((dev->drv->medium_size >> 24) & 0xff);
        buf[pos++] = ((dev->drv->medium_size >> 16) & 0xff);
        buf[pos++] = ((dev->drv->medium_size >> 8) & 0xff);
        buf[pos++] = (dev->drv->medium_size & 0xff);
        buf[pos++] = 0; /* Reserved. */
        buf[pos++] = 0; /* Block length (0x200 = 512 bytes). */
        buf[pos++] = 2;
        buf[pos++] = 0;
    }

    for (uint8_t i = 0; i < 0x40; i++) {
        if ((page == GPMODE_ALL_PAGES) || (page == i)) {
            if (pf & (1LL << ((uint64_t) page))) {
                buf[pos++] = zip_mode_sense_read(dev, page_control, i, 0);
                msplen     = zip_mode_sense_read(dev, page_control, i, 1);
                buf[pos++] = msplen;
                zip_log("ZIP %i: MODE SENSE: Page [%02X] length %i\n", dev->id, i, msplen);
                for (uint8_t j = 0; j < msplen; j++)
                    buf[pos++] = zip_mode_sense_read(dev, page_control, i, 2 + j);
            }
        }
    }

    return pos;
}

static void
zip_update_request_length(zip_t *dev, int len, int block_len)
{
    int bt;
    int min_len = 0;

    dev->max_transfer_len = dev->tf->request_length;

    /* For media access commands, make sure the requested DRQ length matches the block length. */
    switch (dev->current_cdb[0]) {
        case 0x08:
        case 0x0a:
        case 0x28:
        case 0x2a:
        case 0xa8:
        case 0xaa:
            /* Round it to the nearest 2048 bytes. */
            dev->max_transfer_len = (dev->max_transfer_len >> 9) << 9;

            /* Make sure total length is not bigger than sum of the lengths of
               all the requested blocks. */
            bt = (dev->requested_blocks * block_len);
            if (len > bt)
                len = bt;

            min_len = block_len;

            if (len <= block_len) {
                /* Total length is less or equal to block length. */
                if (dev->max_transfer_len < block_len) {
                    /* Transfer a minimum of (block size) bytes. */
                    dev->max_transfer_len = block_len;
                    dev->packet_len       = block_len;
                    break;
                }
            }
            fallthrough;

        default:
            dev->packet_len = len;
            break;
    }
    /* If the DRQ length is odd, and the total remaining length is bigger, make sure it's even. */
    if ((dev->max_transfer_len & 1) && (dev->max_transfer_len < len))
        dev->max_transfer_len &= 0xfffe;
    /* If the DRQ length is smaller or equal in size to the total remaining length, set it to that. */
    if (!dev->max_transfer_len)
        dev->max_transfer_len = 65534;

    if ((len <= dev->max_transfer_len) && (len >= min_len))
        dev->tf->request_length = dev->max_transfer_len = len;
    else if (len > dev->max_transfer_len)
        dev->tf->request_length = dev->max_transfer_len;

    return;
}

static double
zip_bus_speed(zip_t *dev)
{
    double ret = -1.0;

    if (dev && dev->drv && (dev->drv->bus_type == ZIP_BUS_SCSI)) {
        dev->callback = -1.0; /* Speed depends on SCSI controller */
        return 0.0;
    } else {
        if (dev && dev->drv)
            ret = ide_atapi_get_period(dev->drv->ide_channel);
        if (ret == -1.0) {
            if (dev)
                dev->callback = -1.0;
            return 0.0;
        } else
            return ret * 1000000.0;
    }
}

static void
zip_command_common(zip_t *dev)
{
    double bytes_per_second;
    double period;

    dev->tf->status = BUSY_STAT;
    dev->tf->phase  = 1;
    dev->tf->pos    = 0;
    if (dev->packet_status == PHASE_COMPLETE)
        dev->callback = 0.0;
    else {
        if (dev->drv->bus_type == ZIP_BUS_SCSI) {
            dev->callback = -1.0; /* Speed depends on SCSI controller */
            return;
        } else
            bytes_per_second = zip_bus_speed(dev);

        period        = 1000000.0 / bytes_per_second;
        dev->callback = period * (double) (dev->packet_len);
    }

    zip_set_callback(dev);
}

static void
zip_command_complete(zip_t *dev)
{
    ui_sb_update_icon(SB_ZIP | dev->id, 0);
    dev->packet_status = PHASE_COMPLETE;
    zip_command_common(dev);
}

static void
zip_command_read(zip_t *dev)
{
    dev->packet_status = PHASE_DATA_IN;
    zip_command_common(dev);
}

static void
zip_command_read_dma(zip_t *dev)
{
    dev->packet_status = PHASE_DATA_IN_DMA;
    zip_command_common(dev);
}

static void
zip_command_write(zip_t *dev)
{
    dev->packet_status = PHASE_DATA_OUT;
    zip_command_common(dev);
}

static void
zip_command_write_dma(zip_t *dev)
{
    dev->packet_status = PHASE_DATA_OUT_DMA;
    zip_command_common(dev);
}

/* id = Current ZIP device ID;
   len = Total transfer length;
   block_len = Length of a single block (why does it matter?!);
   alloc_len = Allocated transfer length;
   direction = Transfer direction (0 = read from host, 1 = write to host). */
static void
zip_data_command_finish(zip_t *dev, int len, int block_len, int alloc_len, int direction)
{
    zip_log("ZIP %i: Finishing command (%02X): %i, %i, %i, %i, %i\n",
            dev->id, dev->current_cdb[0], len, block_len, alloc_len, direction, dev->tf->request_length);
    dev->tf->pos = 0;
    if (alloc_len >= 0) {
        if (alloc_len < len)
            len = alloc_len;
    }
    if ((len == 0) || (zip_current_mode(dev) == 0)) {
        if (dev->drv->bus_type != ZIP_BUS_SCSI)
            dev->packet_len = 0;

        zip_command_complete(dev);
    } else {
        if (zip_current_mode(dev) == 2) {
            if (dev->drv->bus_type != ZIP_BUS_SCSI)
                dev->packet_len = alloc_len;

            if (direction == 0)
                zip_command_read_dma(dev);
            else
                zip_command_write_dma(dev);
        } else {
            zip_update_request_length(dev, len, block_len);
            if (direction == 0)
                zip_command_read(dev);
            else
                zip_command_write(dev);
        }
    }

    zip_log("ZIP %i: Status: %i, cylinder %i, packet length: %i, position: %i, phase: %i\n",
            dev->id, dev->packet_status, dev->tf->request_length, dev->packet_len, dev->tf->pos,
            dev->tf->phase);
}

static void
zip_sense_clear(zip_t *dev, UNUSED(int command))
{
    zip_sense_key = zip_asc = zip_ascq = 0;
}

static void
zip_set_phase(zip_t *dev, uint8_t phase)
{
    uint8_t scsi_bus = (dev->drv->scsi_device_id >> 4) & 0x0f;
    uint8_t scsi_id  = dev->drv->scsi_device_id & 0x0f;

    if (dev->drv->bus_type != ZIP_BUS_SCSI)
        return;

    scsi_devices[scsi_bus][scsi_id].phase = phase;
}

static void
zip_cmd_error(zip_t *dev)
{
    zip_set_phase(dev, SCSI_PHASE_STATUS);
    dev->tf->error = ((zip_sense_key & 0xf) << 4) | ABRT_ERR;
    if (dev->unit_attention)
        dev->tf->error |= MCR_ERR;
    dev->tf->status    = READY_STAT | ERR_STAT;
    dev->tf->phase     = 3;
    dev->tf->pos       = 0;
    dev->packet_status = PHASE_ERROR;
    dev->callback      = 50.0 * ZIP_TIME;
    zip_set_callback(dev);
    ui_sb_update_icon(SB_ZIP | dev->id, 0);
    zip_log("ZIP %i: [%02X] ERROR: %02X/%02X/%02X\n", dev->id, dev->current_cdb[0], zip_sense_key, zip_asc, zip_ascq);
}

static void
zip_unit_attention(zip_t *dev)
{
    zip_set_phase(dev, SCSI_PHASE_STATUS);
    dev->tf->error = (SENSE_UNIT_ATTENTION << 4) | ABRT_ERR;
    if (dev->unit_attention)
        dev->tf->error |= MCR_ERR;
    dev->tf->status    = READY_STAT | ERR_STAT;
    dev->tf->phase     = 3;
    dev->tf->pos       = 0;
    dev->packet_status = PHASE_ERROR;
    dev->callback      = 50.0 * ZIP_TIME;
    zip_set_callback(dev);
    ui_sb_update_icon(SB_ZIP | dev->id, 0);
    zip_log("ZIP %i: UNIT ATTENTION\n", dev->id);
}

static void
zip_buf_alloc(zip_t *dev, uint32_t len)
{
    zip_log("ZIP %i: Allocated buffer length: %i\n", dev->id, len);
    if (!dev->buffer)
        dev->buffer = (uint8_t *) malloc(len);
}

static void
zip_buf_free(zip_t *dev)
{
    if (dev->buffer) {
        zip_log("ZIP %i: Freeing buffer...\n", dev->id);
        free(dev->buffer);
        dev->buffer = NULL;
    }
}

static void
zip_bus_master_error(scsi_common_t *sc)
{
    zip_t *dev = (zip_t *) sc;

    zip_buf_free(dev);
    zip_sense_key = zip_asc = zip_ascq = 0;
    zip_cmd_error(dev);
}

static void
zip_not_ready(zip_t *dev)
{
    zip_sense_key = SENSE_NOT_READY;
    zip_asc       = ASC_MEDIUM_NOT_PRESENT;
    zip_ascq      = 0;
    zip_cmd_error(dev);
}

static void
zip_write_protected(zip_t *dev)
{
    zip_sense_key = SENSE_UNIT_ATTENTION;
    zip_asc       = ASC_WRITE_PROTECTED;
    zip_ascq      = 0;
    zip_cmd_error(dev);
}

static void
zip_invalid_lun(zip_t *dev)
{
    zip_sense_key = SENSE_ILLEGAL_REQUEST;
    zip_asc       = ASC_INV_LUN;
    zip_ascq      = 0;
    zip_cmd_error(dev);
}

static void
zip_illegal_opcode(zip_t *dev)
{
    zip_sense_key = SENSE_ILLEGAL_REQUEST;
    zip_asc       = ASC_ILLEGAL_OPCODE;
    zip_ascq      = 0;
    zip_cmd_error(dev);
}

static void
zip_lba_out_of_range(zip_t *dev)
{
    zip_sense_key = SENSE_ILLEGAL_REQUEST;
    zip_asc       = ASC_LBA_OUT_OF_RANGE;
    zip_ascq      = 0;
    zip_cmd_error(dev);
}

static void
zip_invalid_field(zip_t *dev)
{
    zip_sense_key = SENSE_ILLEGAL_REQUEST;
    zip_asc       = ASC_INV_FIELD_IN_CMD_PACKET;
    zip_ascq      = 0;
    zip_cmd_error(dev);
    dev->tf->status = 0x53;
}

static void
zip_invalid_field_pl(zip_t *dev)
{
    zip_sense_key = SENSE_ILLEGAL_REQUEST;
    zip_asc       = ASC_INV_FIELD_IN_PARAMETER_LIST;
    zip_ascq      = 0;
    zip_cmd_error(dev);
    dev->tf->status = 0x53;
}

static void
zip_data_phase_error(zip_t *dev)
{
    zip_sense_key = SENSE_ILLEGAL_REQUEST;
    zip_asc       = ASC_DATA_PHASE_ERROR;
    zip_ascq      = 0;
    zip_cmd_error(dev);
}

static int
zip_blocks(zip_t *dev, int32_t *len, UNUSED(int first_batch), int out)
{
    *len = 0;

    if (!dev->sector_len) {
        zip_command_complete(dev);
        return -1;
    }

    zip_log("%sing %i blocks starting from %i...\n", out ? "Writ" : "Read", dev->requested_blocks, dev->sector_pos);

    if (dev->sector_pos >= dev->drv->medium_size) {
        zip_log("ZIP %i: Trying to %s beyond the end of disk\n", dev->id, out ? "write" : "read");
        zip_lba_out_of_range(dev);
        return 0;
    }

    *len = dev->requested_blocks << 9;

    for (int i = 0; i < dev->requested_blocks; i++) {
        if (fseek(dev->drv->fp, dev->drv->base + (dev->sector_pos << 9) + (i << 9), SEEK_SET) == 1)
            break;

        if (feof(dev->drv->fp))
            break;

        if (out) {
            if (fwrite(dev->buffer + (i << 9), 1, 512, dev->drv->fp) != 512)
                fatal("zip_blocks(): Error writing data\n");
        } else {
            if (fread(dev->buffer + (i << 9), 1, 512, dev->drv->fp) != 512)
                fatal("zip_blocks(): Error reading data\n");
        }
    }

    zip_log("%s %i bytes of blocks...\n", out ? "Written" : "Read", *len);

    dev->sector_pos += dev->requested_blocks;
    dev->sector_len -= dev->requested_blocks;

    return 1;
}

void
zip_insert(zip_t *dev)
{
    dev->unit_attention = 1;
}

/*SCSI Sense Initialization*/
void
zip_sense_code_ok(zip_t *dev)
{
    zip_sense_key = SENSE_NONE;
    zip_asc       = 0;
    zip_ascq      = 0;
}

static int
zip_pre_execution_check(zip_t *dev, uint8_t *cdb)
{
    int ready = 0;

    if ((cdb[0] != GPCMD_REQUEST_SENSE) && (dev->cur_lun == SCSI_LUN_USE_CDB) && (cdb[1] & 0xe0)) {
        zip_log("ZIP %i: Attempting to execute a unknown command targeted at SCSI LUN %i\n", dev->id,
                ((dev->tf->request_length >> 5) & 7));
        zip_invalid_lun(dev);
        return 0;
    }

    if (!(zip_command_flags[cdb[0]] & IMPLEMENTED)) {
        zip_log("ZIP %i: Attempting to execute unknown command %02X over %s\n", dev->id, cdb[0],
                (dev->drv->bus_type == ZIP_BUS_SCSI) ? "SCSI" : "ATAPI");

        zip_illegal_opcode(dev);
        return 0;
    }

    if ((dev->drv->bus_type < ZIP_BUS_SCSI) && (zip_command_flags[cdb[0]] & SCSI_ONLY)) {
        zip_log("ZIP %i: Attempting to execute SCSI-only command %02X over ATAPI\n", dev->id, cdb[0]);
        zip_illegal_opcode(dev);
        return 0;
    }

    if ((dev->drv->bus_type == ZIP_BUS_SCSI) && (zip_command_flags[cdb[0]] & ATAPI_ONLY)) {
        zip_log("ZIP %i: Attempting to execute ATAPI-only command %02X over SCSI\n", dev->id, cdb[0]);
        zip_illegal_opcode(dev);
        return 0;
    }

    ready = (dev->drv->fp != NULL);

    /* If the drive is not ready, there is no reason to keep the
       UNIT ATTENTION condition present, as we only use it to mark
       disc changes. */
    if (!ready && dev->unit_attention)
        dev->unit_attention = 0;

    /* If the UNIT ATTENTION condition is set and the command does not allow
       execution under it, error out and report the condition. */
    if (dev->unit_attention == 1) {
        /* Only increment the unit attention phase if the command can not pass through it. */
        if (!(zip_command_flags[cdb[0]] & ALLOW_UA)) {
            /* zip_log("ZIP %i: Unit attention now 2\n", dev->id); */
            dev->unit_attention = 2;
            zip_log("ZIP %i: UNIT ATTENTION: Command %02X not allowed to pass through\n", dev->id, cdb[0]);
            zip_unit_attention(dev);
            return 0;
        }
    } else if (dev->unit_attention == 2) {
        if (cdb[0] != GPCMD_REQUEST_SENSE) {
            /* zip_log("ZIP %i: Unit attention now 0\n", dev->id); */
            dev->unit_attention = 0;
        }
    }

    /* Unless the command is REQUEST SENSE, clear the sense. This will *NOT*
       the UNIT ATTENTION condition if it's set. */
    if (cdb[0] != GPCMD_REQUEST_SENSE)
        zip_sense_clear(dev, cdb[0]);

    /* Next it's time for NOT READY. */
    if ((zip_command_flags[cdb[0]] & CHECK_READY) && !ready) {
        zip_log("ZIP %i: Not ready (%02X)\n", dev->id, cdb[0]);
        zip_not_ready(dev);
        return 0;
    }

    zip_log("ZIP %i: Continuing with command %02X\n", dev->id, cdb[0]);

    return 1;
}

static void
zip_seek(zip_t *dev, uint32_t pos)
{
#if 0
    zip_log("ZIP %i: Seek %08X\n", dev->id, pos);
#endif
    dev->sector_pos = pos;
}

static void
zip_rezero(zip_t *dev)
{
    dev->sector_pos = dev->sector_len = 0;
    zip_seek(dev, 0);
}

void
zip_reset(scsi_common_t *sc)
{
    zip_t *dev = (zip_t *) sc;

    zip_rezero(dev);
    dev->tf->status         = 0;
    dev->callback           = 0.0;
    zip_set_callback(dev);
    dev->tf->phase          = 1;
    dev->tf->request_length = 0xEB14;
    dev->packet_status      = PHASE_NONE;
    dev->unit_attention     = 0;
    dev->cur_lun            = SCSI_LUN_USE_CDB;
}

static void
zip_request_sense(zip_t *dev, uint8_t *buffer, uint8_t alloc_length, int desc)
{
    /*Will return 18 bytes of 0*/
    if (alloc_length != 0) {
        memset(buffer, 0, alloc_length);
        if (!desc)
            memcpy(buffer, dev->sense, alloc_length);
        else {
            buffer[1] = zip_sense_key;
            buffer[2] = zip_asc;
            buffer[3] = zip_ascq;
        }
    }

    buffer[0] = desc ? 0x72 : 0x70;

    if (dev->unit_attention && (zip_sense_key == 0)) {
        buffer[desc ? 1 : 2]  = SENSE_UNIT_ATTENTION;
        buffer[desc ? 2 : 12] = ASC_MEDIUM_MAY_HAVE_CHANGED;
        buffer[desc ? 3 : 13] = 0;
    }

    zip_log("ZIP %i: Reporting sense: %02X %02X %02X\n", dev->id, buffer[2], buffer[12], buffer[13]);

    if (buffer[desc ? 1 : 2] == SENSE_UNIT_ATTENTION) {
        /* If the last remaining sense is unit attention, clear
           that condition. */
        dev->unit_attention = 0;
    }

    /* Clear the sense stuff as per the spec. */
    zip_sense_clear(dev, GPCMD_REQUEST_SENSE);
}

static void
zip_request_sense_for_scsi(scsi_common_t *sc, uint8_t *buffer, uint8_t alloc_length)
{
    zip_t *dev   = (zip_t *) sc;
    int    ready = 0;

    ready = (dev->drv->fp != NULL);

    if (!ready && dev->unit_attention) {
        /* If the drive is not ready, there is no reason to keep the
           UNIT ATTENTION condition present, as we only use it to mark
           disc changes. */
        dev->unit_attention = 0;
    }

    /* Do *NOT* advance the unit attention phase. */

    zip_request_sense(dev, buffer, alloc_length, 0);
}

static void
zip_set_buf_len(zip_t *dev, int32_t *BufLen, int32_t *src_len)
{
    if (dev->drv->bus_type == ZIP_BUS_SCSI) {
        if (*BufLen == -1)
            *BufLen = *src_len;
        else {
            *BufLen  = MIN(*src_len, *BufLen);
            *src_len = *BufLen;
        }
        zip_log("ZIP %i: Actual transfer length: %i\n", dev->id, *BufLen);
    }
}

static void
zip_command(scsi_common_t *sc, uint8_t *cdb)
{
    zip_t   *dev = (zip_t *) sc;
    int      pos = 0;
    int      block_desc = 0;
    int      ret;
    int32_t  len;
    int32_t  max_len;
    int32_t  alloc_length;
    uint32_t i = 0;
    int      size_idx;
    int      idx = 0;
    unsigned preamble_len;
    int32_t  blen = 0;
    int32_t *BufLen;
    uint8_t  scsi_bus = (dev->drv->scsi_device_id >> 4) & 0x0f;
    uint8_t  scsi_id  = dev->drv->scsi_device_id & 0x0f;

    if (dev->drv->bus_type == ZIP_BUS_SCSI) {
        BufLen          = &scsi_devices[scsi_bus][scsi_id].buffer_length;
        dev->tf->status &= ~ERR_STAT;
    } else {
        BufLen         = &blen;
        dev->tf->error = 0;
    }

    dev->packet_len  = 0;
    dev->request_pos = 0;

    memcpy(dev->current_cdb, cdb, 12);

    if (cdb[0] != 0) {
        zip_log("ZIP %i: Command 0x%02X, Sense Key %02X, Asc %02X, Ascq %02X, Unit attention: %i\n",
                dev->id, cdb[0], zip_sense_key, zip_asc, zip_ascq, dev->unit_attention);
        zip_log("ZIP %i: Request length: %04X\n", dev->id, dev->tf->request_length);

        zip_log("ZIP %i: CDB: %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X\n", dev->id,
                cdb[0], cdb[1], cdb[2], cdb[3], cdb[4], cdb[5], cdb[6], cdb[7],
                cdb[8], cdb[9], cdb[10], cdb[11]);
    }

    dev->sector_len = 0;

    zip_set_phase(dev, SCSI_PHASE_STATUS);

    /* This handles the Not Ready/Unit Attention check if it has to be handled at this point. */
    if (zip_pre_execution_check(dev, cdb) == 0)
        return;

    switch (cdb[0]) {
        case GPCMD_SEND_DIAGNOSTIC:
            if (!(cdb[1] & (1 << 2))) {
                zip_invalid_field(dev);
                return;
            }
            fallthrough;
        case GPCMD_SCSI_RESERVE:
        case GPCMD_SCSI_RELEASE:
        case GPCMD_TEST_UNIT_READY:
            zip_set_phase(dev, SCSI_PHASE_STATUS);
            zip_command_complete(dev);
            break;

        case GPCMD_FORMAT_UNIT:
            if (dev->drv->read_only) {
                zip_write_protected(dev);
                return;
            }

            zip_set_phase(dev, SCSI_PHASE_STATUS);
            zip_command_complete(dev);
            break;

        case GPCMD_IOMEGA_SENSE:
            zip_set_phase(dev, SCSI_PHASE_DATA_IN);
            max_len = cdb[4];
            zip_buf_alloc(dev, 256);
            zip_set_buf_len(dev, BufLen, &max_len);
            memset(dev->buffer, 0, 256);
            if (cdb[2] == 1) {
                /* This page is related to disk health status - setting
                   this page to 0 makes disk health read as "marginal". */
                dev->buffer[0] = 0x58;
                dev->buffer[1] = 0x00;
                for (i = 0x00; i < 0x58; i++)
                    dev->buffer[i + 0x02] = 0xff;
            } else if (cdb[2] == 2) {
                dev->buffer[0] = 0x3d;
                dev->buffer[1] = 0x00;
                for (i = 0x00; i < 0x13; i++)
                    dev->buffer[i + 0x02] = 0x00;
                dev->buffer[0x15] = 0x00;
                if (dev->drv->read_only)
                    dev->buffer[0x15] |= 0x02;
                for (i = 0x00; i < 0x27; i++)
                    dev->buffer[i + 0x16] = 0x00;
            } else {
                zip_invalid_field(dev);
                zip_buf_free(dev);
                return;
            }
            zip_data_command_finish(dev, 18, 18, cdb[4], 0);
            break;

        case GPCMD_REZERO_UNIT:
            dev->sector_pos = dev->sector_len = 0;
            zip_seek(dev, 0);
            zip_set_phase(dev, SCSI_PHASE_STATUS);
            break;

        case GPCMD_REQUEST_SENSE:
            /* If there's a unit attention condition and there's a buffered not
               ready, a standalone REQUEST SENSE should forget about the not
               ready, and report unit attention straight away. */
            zip_set_phase(dev, SCSI_PHASE_DATA_IN);
            max_len = cdb[4];

            if (!max_len) {
                zip_set_phase(dev, SCSI_PHASE_STATUS);
                dev->packet_status = PHASE_COMPLETE;
                dev->callback      = 20.0 * ZIP_TIME;
                zip_set_callback(dev);
                break;
            }

            zip_buf_alloc(dev, 256);
            zip_set_buf_len(dev, BufLen, &max_len);
            len = (cdb[1] & 1) ? 8 : 18;
            zip_request_sense(dev, dev->buffer, max_len, cdb[1] & 1);
            zip_data_command_finish(dev, len, len, cdb[4], 0);
            break;

        case GPCMD_MECHANISM_STATUS:
            zip_set_phase(dev, SCSI_PHASE_DATA_IN);
            len = (cdb[8] << 8) | cdb[9];

            zip_buf_alloc(dev, 8);
            zip_set_buf_len(dev, BufLen, &len);

            memset(dev->buffer, 0, 8);
            dev->buffer[5] = 1;

            zip_data_command_finish(dev, 8, 8, len, 0);
            break;

        case GPCMD_READ_6:
        case GPCMD_READ_10:
        case GPCMD_READ_12:
            zip_set_phase(dev, SCSI_PHASE_DATA_IN);
            alloc_length = 512;

            switch (cdb[0]) {
                case GPCMD_READ_6:
                    dev->sector_len = cdb[4];
                    /*
                       For READ (6) and WRITE (6), a length of 0 indicates a
                       transfer of 256 sectors.
                     */
                    if (dev->sector_len == 0)
                        dev->sector_len = 256;
                    dev->sector_pos = ((((uint32_t) cdb[1]) & 0x1f) << 16) |
                                      (((uint32_t) cdb[2]) << 8) | ((uint32_t) cdb[3]);
                    zip_log("ZIP %i: Length: %i, LBA: %i\n", dev->id, dev->sector_len, dev->sector_pos);
                    break;
                case GPCMD_READ_10:
                    dev->sector_len = (cdb[7] << 8) | cdb[8];
                    dev->sector_pos = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
                    zip_log("ZIP %i: Length: %i, LBA: %i\n", dev->id, dev->sector_len, dev->sector_pos);
                    break;
                case GPCMD_READ_12:
                    dev->sector_len = (((uint32_t) cdb[6]) << 24) | (((uint32_t) cdb[7]) << 16) |
                                      (((uint32_t) cdb[8]) << 8) | ((uint32_t) cdb[9]);
                    dev->sector_pos = (((uint32_t) cdb[2]) << 24) | (((uint32_t) cdb[3]) << 16) |
                                      (((uint32_t) cdb[4]) << 8) | ((uint32_t) cdb[5]);
                    break;

                default:
                    break;
            }

            if (dev->sector_pos >= dev->drv->medium_size) {
                zip_lba_out_of_range(dev);
                return;
            }

            if (!dev->sector_len) {
                zip_set_phase(dev, SCSI_PHASE_STATUS);
                /* zip_log("ZIP %i: All done - callback set\n", dev->id); */
                dev->packet_status = PHASE_COMPLETE;
                dev->callback      = 20.0 * ZIP_TIME;
                zip_set_callback(dev);
                break;
            }

            max_len               = dev->sector_len;
            /*
               If we're reading all blocks in one go for DMA, why not also for
               PIO, it should NOT matter anyway, this step should be identical
               and only the way the read dat is transferred to the host should
               be different.
             */
            dev->requested_blocks = max_len;

            dev->packet_len = max_len * alloc_length;
            zip_buf_alloc(dev, dev->packet_len);

            ret = zip_blocks(dev, &alloc_length, 1, 0);
            if (ret <= 0) {
                zip_set_phase(dev, SCSI_PHASE_STATUS);
                dev->packet_status = PHASE_COMPLETE;
                dev->callback      = 20.0 * ZIP_TIME;
                zip_set_callback(dev);
                zip_buf_free(dev);
                return;
            }

            dev->requested_blocks = max_len;
            dev->packet_len       = alloc_length;

            zip_set_buf_len(dev, BufLen, (int32_t *) &dev->packet_len);

            zip_data_command_finish(dev, alloc_length, 512, alloc_length, 0);

            ui_sb_update_icon(SB_ZIP | dev->id, dev->packet_status != PHASE_COMPLETE);
            return;

        case GPCMD_VERIFY_6:
        case GPCMD_VERIFY_10:
        case GPCMD_VERIFY_12:
            if (!(cdb[1] & 2)) {
                zip_set_phase(dev, SCSI_PHASE_STATUS);
                zip_command_complete(dev);
                break;
            }
            fallthrough;
        case GPCMD_WRITE_6:
        case GPCMD_WRITE_10:
        case GPCMD_WRITE_AND_VERIFY_10:
        case GPCMD_WRITE_12:
        case GPCMD_WRITE_AND_VERIFY_12:
            zip_set_phase(dev, SCSI_PHASE_DATA_OUT);
            alloc_length = 512;

            if (dev->drv->read_only) {
                zip_write_protected(dev);
                return;
            }

            switch (cdb[0]) {
                case GPCMD_VERIFY_6:
                case GPCMD_WRITE_6:
                    dev->sector_len = cdb[4];
                    /*
                       For READ (6) and WRITE (6), a length of 0 indicates a
                       transfer of 256 sectors.
                     */
                    if (dev->sector_len == 0)
                        dev->sector_len = 256;
                    dev->sector_pos = ((((uint32_t) cdb[1]) & 0x1f) << 16) |
                                      (((uint32_t) cdb[2]) << 8) | ((uint32_t) cdb[3]);
                    break;
                case GPCMD_VERIFY_10:
                case GPCMD_WRITE_10:
                case GPCMD_WRITE_AND_VERIFY_10:
                    dev->sector_len = (cdb[7] << 8) | cdb[8];
                    dev->sector_pos = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
                    zip_log("ZIP %i: Length: %i, LBA: %i\n", dev->id, dev->sector_len, dev->sector_pos);
                    break;
                case GPCMD_VERIFY_12:
                case GPCMD_WRITE_12:
                case GPCMD_WRITE_AND_VERIFY_12:
                    dev->sector_len = (((uint32_t) cdb[6]) << 24) | (((uint32_t) cdb[7]) << 16) |
                                      (((uint32_t) cdb[8]) << 8) | ((uint32_t) cdb[9]);
                    dev->sector_pos = (((uint32_t) cdb[2]) << 24) | (((uint32_t) cdb[3]) << 16) |
                                      (((uint32_t) cdb[4]) << 8) | ((uint32_t) cdb[5]);
                    break;

                default:
                    break;
            }

            if (dev->sector_pos >= dev->drv->medium_size) {
                zip_lba_out_of_range(dev);
                return;
            }

            if (!dev->sector_len) {
                zip_set_phase(dev, SCSI_PHASE_STATUS);
                /* zip_log("ZIP %i: All done - callback set\n", dev->id); */
                dev->packet_status = PHASE_COMPLETE;
                dev->callback      = 20.0 * ZIP_TIME;
                zip_set_callback(dev);
                break;
            }

            max_len               = dev->sector_len;
            /*
               If we're writing all blocks in one go for DMA, why not also for
               PIO, it should NOT matter anyway, this step should be identical
               and only the way the read dat is transferred to the host should
               be different.
             */
            dev->requested_blocks = max_len;

            dev->packet_len = max_len * alloc_length;
            zip_buf_alloc(dev, dev->packet_len);

            dev->requested_blocks = max_len;
            dev->packet_len       = max_len << 9;

            zip_set_buf_len(dev, BufLen, (int32_t *) &dev->packet_len);

            zip_data_command_finish(dev, dev->packet_len, 512, dev->packet_len, 1);

            ui_sb_update_icon(SB_ZIP | dev->id, dev->packet_status != PHASE_COMPLETE);
            return;

        case GPCMD_WRITE_SAME_10:
            alloc_length = 512;

            if ((cdb[1] & 6) == 6) {
                zip_invalid_field(dev);
                return;
            }

            if (dev->drv->read_only) {
                zip_write_protected(dev);
                return;
            }

            dev->sector_len = (cdb[7] << 8) | cdb[8];
            dev->sector_pos = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];

            if (dev->sector_pos >= dev->drv->medium_size) {
                zip_lba_out_of_range(dev);
                return;
            }

            if (!dev->sector_len) {
                zip_set_phase(dev, SCSI_PHASE_STATUS);
                /* zip_log("ZIP %i: All done - callback set\n", dev->id); */
                dev->packet_status = PHASE_COMPLETE;
                dev->callback      = 20.0 * ZIP_TIME;
                zip_set_callback(dev);
                break;
            }

            zip_buf_alloc(dev, alloc_length);
            zip_set_buf_len(dev, BufLen, (int32_t *) &dev->packet_len);

            max_len               = 1;
            dev->requested_blocks = 1;

            dev->packet_len = alloc_length;

            zip_set_phase(dev, SCSI_PHASE_DATA_OUT);

            zip_data_command_finish(dev, 512, 512, alloc_length, 1);

            ui_sb_update_icon(SB_ZIP | dev->id, dev->packet_status != PHASE_COMPLETE);
            return;

        case GPCMD_MODE_SENSE_6:
        case GPCMD_MODE_SENSE_10:
            zip_set_phase(dev, SCSI_PHASE_DATA_IN);

            if (dev->drv->bus_type == ZIP_BUS_SCSI)
                block_desc = ((cdb[1] >> 3) & 1) ? 0 : 1;
            else
                block_desc = 0;

            if (cdb[0] == GPCMD_MODE_SENSE_6) {
                len = cdb[4];
                zip_buf_alloc(dev, 256);
            } else {
                len = (cdb[8] | (cdb[7] << 8));
                zip_buf_alloc(dev, 65536);
            }

            if (!(zip_mode_sense_page_flags & (1LL << (uint64_t) (cdb[2] & 0x3f)))) {
                zip_invalid_field(dev);
                zip_buf_free(dev);
                return;
            }

            memset(dev->buffer, 0, len);
            alloc_length = len;

            if (cdb[0] == GPCMD_MODE_SENSE_6) {
                len            = zip_mode_sense(dev, dev->buffer, 4, cdb[2], block_desc);
                len            = MIN(len, alloc_length);
                dev->buffer[0] = len - 1;
                dev->buffer[1] = 0;
                if (block_desc)
                    dev->buffer[3] = 8;
            } else {
                len            = zip_mode_sense(dev, dev->buffer, 8, cdb[2], block_desc);
                len            = MIN(len, alloc_length);
                dev->buffer[0] = (len - 2) >> 8;
                dev->buffer[1] = (len - 2) & 255;
                dev->buffer[2] = 0;
                if (block_desc) {
                    dev->buffer[6] = 0;
                    dev->buffer[7] = 8;
                }
            }

            zip_set_buf_len(dev, BufLen, &len);

            zip_log("ZIP %i: Reading mode page: %02X...\n", dev->id, cdb[2]);

            zip_data_command_finish(dev, len, len, alloc_length, 0);
            return;

        case GPCMD_MODE_SELECT_6:
        case GPCMD_MODE_SELECT_10:
            zip_set_phase(dev, SCSI_PHASE_DATA_OUT);

            if (cdb[0] == GPCMD_MODE_SELECT_6) {
                len = cdb[4];
                zip_buf_alloc(dev, 256);
            } else {
                len = (cdb[7] << 8) | cdb[8];
                zip_buf_alloc(dev, 65536);
            }

            zip_set_buf_len(dev, BufLen, &len);

            dev->total_length = len;
            dev->do_page_save = cdb[1] & 1;

            zip_data_command_finish(dev, len, len, len, 1);
            return;

        case GPCMD_START_STOP_UNIT:
            zip_set_phase(dev, SCSI_PHASE_STATUS);

            switch (cdb[4] & 3) {
                case 0:                 /* Stop the disc. */
                    zip_eject(dev->id); /* The Iomega Windows 9x drivers require this. */
                    break;
                case 1: /* Start the disc and read the TOC. */
                    break;
                case 2: /* Eject the disc if possible. */
#if 0
                    zip_eject(dev->id);
#endif
                    break;
                case 3: /* Load the disc (close tray). */
                    zip_reload(dev->id);
                    break;

                default:
                    break;
            }

            zip_command_complete(dev);
            break;

        case GPCMD_INQUIRY:
            zip_set_phase(dev, SCSI_PHASE_DATA_IN);

            max_len = cdb[3];
            max_len <<= 8;
            max_len |= cdb[4];

            zip_buf_alloc(dev, 65536);

            if (cdb[1] & 1) {
                preamble_len = 4;
                size_idx     = 3;

                dev->buffer[idx++] = 0;
                dev->buffer[idx++] = cdb[2];
                dev->buffer[idx++] = 0;

                idx++;

                switch (cdb[2]) {
                    case 0x00:
                        dev->buffer[idx++] = 0x00;
                        dev->buffer[idx++] = 0x83;
                        break;
                    case 0x83:
                        if (idx + 24 > max_len) {
                            zip_data_phase_error(dev);
                            zip_buf_free(dev);
                            return;
                        }

                        dev->buffer[idx++] = 0x02;
                        dev->buffer[idx++] = 0x00;
                        dev->buffer[idx++] = 0x00;
                        dev->buffer[idx++] = 20;
                        ide_padstr8(dev->buffer + idx, 20, "53R141"); /* Serial */
                        idx += 20;

                        if (idx + 72 > cdb[4])
                            goto atapi_out;
                        dev->buffer[idx++] = 0x02;
                        dev->buffer[idx++] = 0x01;
                        dev->buffer[idx++] = 0x00;
                        dev->buffer[idx++] = 68;
                        ide_padstr8(dev->buffer + idx, 8, "IOMEGA  "); /* Vendor */
                        idx += 8;
                        if (dev->drv->is_250)
                            ide_padstr8(dev->buffer + idx, 40, "ZIP 250         "); /* Product */
                        else
                            ide_padstr8(dev->buffer + idx, 40, "ZIP 100         "); /* Product */
                        idx += 40;
                        ide_padstr8(dev->buffer + idx, 20, "53R141"); /* Product */
                        idx += 20;
                        break;
                    default:
                        zip_log("INQUIRY: Invalid page: %02X\n", cdb[2]);
                        zip_invalid_field(dev);
                        zip_buf_free(dev);
                        return;
                }
            } else {
                preamble_len = 5;
                size_idx     = 4;

                memset(dev->buffer, 0, 8);
                if (cdb[1] & 0xe0)
                    dev->buffer[0] = 0x60; /*No physical device on this LUN*/
                else
                    dev->buffer[0] = 0x00;                                           /*Hard disk*/
                dev->buffer[1] = 0x80;                                               /*Removable*/
                dev->buffer[2] = (dev->drv->bus_type == ZIP_BUS_SCSI) ? 0x02 : 0x00; /*SCSI-2 compliant*/
                dev->buffer[3] = (dev->drv->bus_type == ZIP_BUS_SCSI) ? 0x02 : 0x21;
#if 0
                dev->buffer[4] = 31;
#endif
                dev->buffer[4] = 0;
                if (dev->drv->bus_type == ZIP_BUS_SCSI) {
                    dev->buffer[6] = 1;    /* 16-bit transfers supported */
                    dev->buffer[7] = 0x20; /* Wide bus supported */
                }
                dev->buffer[7] |= 0x02;

                ide_padstr8(dev->buffer + 8, 8, "IOMEGA  "); /* Vendor */
                if (dev->drv->is_250) {
                    ide_padstr8(dev->buffer + 16, 16, "ZIP 250         "); /* Product */
                    ide_padstr8(dev->buffer + 32, 4, "42.S");              /* Revision */
                    if (max_len >= 44)
                        ide_padstr8(dev->buffer + 36, 8, "08/08/01"); /* Date? */
                    if (max_len >= 122)
                        ide_padstr8(dev->buffer + 96, 26, "(c) Copyright IOMEGA 2000 "); /* Copyright string */
                } else {
                    ide_padstr8(dev->buffer + 16, 16, "ZIP 100         "); /* Product */
                    ide_padstr8(dev->buffer + 32, 4, "E.08");              /* Revision */
                }
                idx = 36;

                if (max_len == 96) {
                    dev->buffer[4] = 91;
                    idx            = 96;
                } else if (max_len == 128) {
                    dev->buffer[4] = 0x75;
                    idx            = 128;
                }
            }

atapi_out:
            dev->buffer[size_idx] = idx - preamble_len;
            len                   = idx;

            len = MIN(len, max_len);
            zip_set_buf_len(dev, BufLen, &len);

            zip_data_command_finish(dev, len, len, max_len, 0);
            break;

        case GPCMD_PREVENT_REMOVAL:
            zip_set_phase(dev, SCSI_PHASE_STATUS);
            zip_command_complete(dev);
            break;

        case GPCMD_SEEK_6:
        case GPCMD_SEEK_10:
            zip_set_phase(dev, SCSI_PHASE_STATUS);

            switch (cdb[0]) {
                case GPCMD_SEEK_6:
                    pos = (cdb[2] << 8) | cdb[3];
                    break;
                case GPCMD_SEEK_10:
                    pos = (cdb[2] << 24) | (cdb[3] << 16) | (cdb[4] << 8) | cdb[5];
                    break;

                default:
                    break;
            }
            zip_seek(dev, pos);
            zip_command_complete(dev);
            break;

        case GPCMD_READ_CDROM_CAPACITY:
            zip_set_phase(dev, SCSI_PHASE_DATA_IN);

            zip_buf_alloc(dev, 8);

            max_len = dev->drv->medium_size - 1; /* IMPORTANT: What's returned is the last LBA block. */
            memset(dev->buffer, 0, 8);
            dev->buffer[0] = (max_len >> 24) & 0xff;
            dev->buffer[1] = (max_len >> 16) & 0xff;
            dev->buffer[2] = (max_len >> 8) & 0xff;
            dev->buffer[3] = max_len & 0xff;
            dev->buffer[6] = 2; /* 512 = 0x0200 */
            len            = 8;

            zip_set_buf_len(dev, BufLen, &len);

            zip_data_command_finish(dev, len, len, len, 0);
            break;

        case GPCMD_IOMEGA_EJECT:
            zip_set_phase(dev, SCSI_PHASE_STATUS);
            zip_eject(dev->id);
            zip_command_complete(dev);
            break;

        case GPCMD_READ_FORMAT_CAPACITIES:
            len = (cdb[7] << 8) | cdb[8];

            zip_buf_alloc(dev, len);
            memset(dev->buffer, 0, len);

            pos = 0;

            /* List header */
            dev->buffer[pos++] = 0;
            dev->buffer[pos++] = 0;
            dev->buffer[pos++] = 0;
            if (dev->drv->fp != NULL)
                dev->buffer[pos++] = 16;
            else
                dev->buffer[pos++] = 8;

            /* Current/Maximum capacity header */
            if (dev->drv->is_250) {
                /* ZIP 250 also supports ZIP 100 media, so if the medium is inserted,
                   we return the inserted medium's size, otherwise, the ZIP 250 size. */
                if (dev->drv->fp != NULL) {
                    dev->buffer[pos++] = (dev->drv->medium_size >> 24) & 0xff;
                    dev->buffer[pos++] = (dev->drv->medium_size >> 16) & 0xff;
                    dev->buffer[pos++] = (dev->drv->medium_size >> 8) & 0xff;
                    dev->buffer[pos++] = dev->drv->medium_size & 0xff;
                    dev->buffer[pos++] = 2; /* Current medium capacity */
                } else {
                    dev->buffer[pos++] = (ZIP_250_SECTORS >> 24) & 0xff;
                    dev->buffer[pos++] = (ZIP_250_SECTORS >> 16) & 0xff;
                    dev->buffer[pos++] = (ZIP_250_SECTORS >> 8) & 0xff;
                    dev->buffer[pos++] = ZIP_250_SECTORS & 0xff;
                    dev->buffer[pos++] = 3; /* Maximum medium capacity */
                }
            } else {
                /* ZIP 100 only supports ZIP 100 media as well, so we always return
                   the ZIP 100 size. */
                dev->buffer[pos++] = (ZIP_SECTORS >> 24) & 0xff;
                dev->buffer[pos++] = (ZIP_SECTORS >> 16) & 0xff;
                dev->buffer[pos++] = (ZIP_SECTORS >> 8) & 0xff;
                dev->buffer[pos++] = ZIP_SECTORS & 0xff;
                if (dev->drv->fp != NULL)
                    dev->buffer[pos++] = 2;
                else
                    dev->buffer[pos++] = 3;
            }

            dev->buffer[pos++] = 512 >> 16;
            dev->buffer[pos++] = 512 >> 8;
            dev->buffer[pos++] = 512 & 0xff;

            if (dev->drv->fp != NULL) {
                /* Formattable capacity descriptor */
                dev->buffer[pos++] = (dev->drv->medium_size >> 24) & 0xff;
                dev->buffer[pos++] = (dev->drv->medium_size >> 16) & 0xff;
                dev->buffer[pos++] = (dev->drv->medium_size >> 8) & 0xff;
                dev->buffer[pos++] = dev->drv->medium_size & 0xff;
                dev->buffer[pos++] = 0;
                dev->buffer[pos++] = 512 >> 16;
                dev->buffer[pos++] = 512 >> 8;
                dev->buffer[pos++] = 512 & 0xff;
            }

            zip_set_buf_len(dev, BufLen, &len);

            zip_data_command_finish(dev, len, len, len, 0);
            break;

        default:
            zip_illegal_opcode(dev);
            break;
    }

#if 0
    zip_log("ZIP %i: Phase: %02X, request length: %i\n", dev->id, dev->tf->phase, dev->tf->request_length);
#endif

    if ((dev->packet_status == PHASE_COMPLETE) || (dev->packet_status == PHASE_ERROR))
        zip_buf_free(dev);
}

static void
zip_command_stop(scsi_common_t *sc)
{
    zip_t *dev = (zip_t *) sc;

    zip_command_complete(dev);
    zip_buf_free(dev);
}

/* The command second phase function, needed for Mode Select. */
static uint8_t
zip_phase_data_out(scsi_common_t *sc)
{
    zip_t *dev = (zip_t *) sc;

    uint16_t block_desc_len;
    uint16_t pos;
    uint16_t param_list_len;

    uint8_t error = 0;
    uint8_t page;
    uint8_t page_len;

    uint32_t i = 0;

    uint8_t hdr_len;
    uint8_t val;
    uint8_t old_val;
    uint8_t ch;

    uint32_t last_to_write = 0;
    uint32_t c;
    uint32_t h;
    uint32_t s;

    int len = 0;

    switch (dev->current_cdb[0]) {
        case GPCMD_VERIFY_6:
        case GPCMD_VERIFY_10:
        case GPCMD_VERIFY_12:
            break;
        case GPCMD_WRITE_6:
        case GPCMD_WRITE_10:
        case GPCMD_WRITE_AND_VERIFY_10:
        case GPCMD_WRITE_12:
        case GPCMD_WRITE_AND_VERIFY_12:
            if (dev->requested_blocks > 0)
                zip_blocks(dev, &len, 1, 1);
            break;
        case GPCMD_WRITE_SAME_10:
            if (!dev->current_cdb[7] && !dev->current_cdb[8]) {
                last_to_write = (dev->drv->medium_size - 1);
            } else
                last_to_write = dev->sector_pos + dev->sector_len - 1;

            for (i = dev->sector_pos; i <= last_to_write; i++) {
                if (dev->current_cdb[1] & 2) {
                    dev->buffer[0] = (i >> 24) & 0xff;
                    dev->buffer[1] = (i >> 16) & 0xff;
                    dev->buffer[2] = (i >> 8) & 0xff;
                    dev->buffer[3] = i & 0xff;
                } else if (dev->current_cdb[1] & 4) {
                    /* CHS are 96, 1, 2048 (ZIP 100) and 239, 1, 2048 (ZIP 250) */
                    s              = (i % 2048);
                    h              = ((i - s) / 2048) % 1;
                    c              = ((i - s) / 2048) / 1;
                    dev->buffer[0] = (c >> 16) & 0xff;
                    dev->buffer[1] = (c >> 8) & 0xff;
                    dev->buffer[2] = c & 0xff;
                    dev->buffer[3] = h & 0xff;
                    dev->buffer[4] = (s >> 24) & 0xff;
                    dev->buffer[5] = (s >> 16) & 0xff;
                    dev->buffer[6] = (s >> 8) & 0xff;
                    dev->buffer[7] = s & 0xff;
                }
                if (fseek(dev->drv->fp, dev->drv->base + (i << 9), SEEK_SET) == -1)
                    fatal("zip_phase_data_out(): Error seeking\n");
                if (fwrite(dev->buffer, 1, 512, dev->drv->fp) != 512)
                    fatal("zip_phase_data_out(): Error writing data\n");
            }
            break;
        case GPCMD_MODE_SELECT_6:
        case GPCMD_MODE_SELECT_10:
            if (dev->current_cdb[0] == GPCMD_MODE_SELECT_10) {
                hdr_len        = 8;
                param_list_len = dev->current_cdb[7];
                param_list_len <<= 8;
                param_list_len |= dev->current_cdb[8];
            } else {
                hdr_len        = 4;
                param_list_len = dev->current_cdb[4];
            }

            if (dev->drv->bus_type == ZIP_BUS_SCSI) {
                if (dev->current_cdb[0] == GPCMD_MODE_SELECT_6) {
                    block_desc_len = dev->buffer[2];
                    block_desc_len <<= 8;
                    block_desc_len |= dev->buffer[3];
                } else {
                    block_desc_len = dev->buffer[6];
                    block_desc_len <<= 8;
                    block_desc_len |= dev->buffer[7];
                }
            } else
                block_desc_len = 0;

            pos = hdr_len + block_desc_len;

            while (1) {
                if (pos >= param_list_len) {
                    zip_log("ZIP %i: Buffer has only block descriptor\n", dev->id);
                    break;
                }

                page     = dev->buffer[pos] & 0x3F;
                page_len = dev->buffer[pos + 1];

                pos += 2;

                if (!(zip_mode_sense_page_flags & (1LL << ((uint64_t) page))))
                    error |= 1;
                else {
                    for (i = 0; i < page_len; i++) {
                        ch      = zip_mode_sense_pages_changeable.pages[page][i + 2];
                        val     = dev->buffer[pos + i];
                        old_val = dev->ms_pages_saved.pages[page][i + 2];
                        if (val != old_val) {
                            if (ch)
                                dev->ms_pages_saved.pages[page][i + 2] = val;
                            else
                                error |= 1;
                        }
                    }
                }

                pos += page_len;

                if (dev->drv->bus_type == ZIP_BUS_SCSI)
                    val = zip_mode_sense_pages_default_scsi.pages[page][0] & 0x80;
                else
                    val = zip_mode_sense_pages_default.pages[page][0] & 0x80;
                if (dev->do_page_save && val)
                    zip_mode_sense_save(dev);

                if (pos >= dev->total_length)
                    break;
            }

            if (error) {
                zip_buf_free(dev);
                zip_invalid_field_pl(dev);
                return 0;
            }
            break;

        default:
            break;
    }

    zip_command_stop((scsi_common_t *) dev);
    return 1;
}

/* Peform a master init on the entire module. */
void
zip_global_init(void)
{
    /* Clear the global data. */
    memset(zip_drives, 0x00, sizeof(zip_drives));
}

static int
zip_get_max(int ide_has_dma, int type)
{
    int ret;

    switch (type) {
        case TYPE_PIO:
            ret = ide_has_dma ? 3 : 0;
            break;
        case TYPE_SDMA:
        default:
            ret = -1;
            break;
        case TYPE_MDMA:
            ret = ide_has_dma ? 1 : -1;
            break;
        case TYPE_UDMA:
            ret = ide_has_dma ? 5 : -1;
            break;
    }

    return ret;
}

static int
zip_get_timings(int ide_has_dma, int type)
{
    int ret;

    switch (type) {
        case TIMINGS_DMA:
            ret = ide_has_dma ? 0x96 : 0;
            break;
        case TIMINGS_PIO:
            ret = ide_has_dma ? 0xb4 : 0;
            break;
        case TIMINGS_PIO_FC:
            ret = ide_has_dma ? 0xb4 : 0;
            break;
        default:
            ret = 0;
            break;
    }

    return ret;
}

static void
zip_100_identify(ide_t *ide)
{
    ide_padstr((char *) (ide->buffer + 23), "E.08", 8);                  /* Firmware */
    ide_padstr((char *) (ide->buffer + 27), "IOMEGA ZIP 100 ATAPI", 40); /* Model */
}

static void
zip_250_identify(ide_t *ide, int ide_has_dma)
{
    ide_padstr((char *) (ide->buffer + 23), "42.S", 8);                         /* Firmware */
    ide_padstr((char *) (ide->buffer + 27), "IOMEGA  ZIP 250       ATAPI", 40); /* Model */

    if (ide_has_dma) {
        ide->buffer[80] = 0x70; /*Supported ATA versions : ATA/ATAPI-4 ATA/ATAPI-6*/
        ide->buffer[81] = 0x19; /*Maximum ATA revision supported : ATA/ATAPI-6 T13 1410D revision 3a*/
    }
}

static void
zip_identify(ide_t *ide, int ide_has_dma)
{
    const zip_t *zip;

    zip = (zip_t *) ide->sc;

    /* ATAPI device, direct-access device, removable media, interrupt DRQ:

       Using (2 << 5) below makes the ASUS P/I-P54TP4XE misdentify the ZIP drive
       as a LS-120. */
    ide->buffer[0] = 0x8000 | (0 << 8) | 0x80 | (1 << 5);
    ide_padstr((char *) (ide->buffer + 10), "", 20); /* Serial Number */
    ide->buffer[49]  = 0x200;                        /* LBA supported */
    ide->buffer[126] = 0xfffe;                       /* Interpret zero byte count limit as maximum length */

    if (zip_drives[zip->id].is_250)
        zip_250_identify(ide, ide_has_dma);
    else
        zip_100_identify(ide);
}

static void
zip_drive_reset(int c)
{
    zip_t         *dev;
    scsi_device_t *sd;
    ide_t         *id;
    uint8_t        scsi_bus = (zip_drives[c].scsi_device_id >> 4) & 0x0f;
    uint8_t        scsi_id  = zip_drives[c].scsi_device_id & 0x0f;

    if (!zip_drives[c].priv) {
        zip_drives[c].priv = (zip_t *) malloc(sizeof(zip_t));
        memset(zip_drives[c].priv, 0, sizeof(zip_t));
    }

    dev = (zip_t *) zip_drives[c].priv;

    dev->id      = c;
    dev->cur_lun = SCSI_LUN_USE_CDB;

    if (zip_drives[c].bus_type == ZIP_BUS_SCSI) {
        if (!dev->tf)
            dev->tf        = (ide_tf_t *) calloc(1, sizeof(ide_tf_t));

        /* SCSI ZIP, attach to the SCSI bus. */
        sd = &scsi_devices[scsi_bus][scsi_id];

        sd->sc             = (scsi_common_t *) dev;
        sd->command        = zip_command;
        sd->request_sense  = zip_request_sense_for_scsi;
        sd->reset          = zip_reset;
        sd->phase_data_out = zip_phase_data_out;
        sd->command_stop   = zip_command_stop;
        sd->type           = SCSI_REMOVABLE_DISK;
    } else if (zip_drives[c].bus_type == ZIP_BUS_ATAPI) {
        /* ATAPI CD-ROM, attach to the IDE bus. */
        id = ide_get_drive(zip_drives[c].ide_channel);
        /* If the IDE channel is initialized, we attach to it,
           otherwise, we do nothing - it's going to be a drive
           that's not attached to anything. */
        if (id) {
            id->sc               = (scsi_common_t *) dev;
            dev->tf              = id->tf;
            IDE_ATAPI_IS_EARLY   = 0;
            id->get_max          = zip_get_max;
            id->get_timings      = zip_get_timings;
            id->identify         = zip_identify;
            id->stop             = NULL;
            id->packet_command   = zip_command;
            id->device_reset     = zip_reset;
            id->phase_data_out   = zip_phase_data_out;
            id->command_stop     = zip_command_stop;
            id->bus_master_error = zip_bus_master_error;
            id->interrupt_drq    = 1;

            ide_atapi_attach(id);
        }
    }
}

void
zip_hard_reset(void)
{
    zip_t  *dev;
    uint8_t scsi_id;
    uint8_t scsi_bus;

    for (uint8_t c = 0; c < ZIP_NUM; c++) {
        if ((zip_drives[c].bus_type == ZIP_BUS_ATAPI) || (zip_drives[c].bus_type == ZIP_BUS_SCSI)) {
            zip_log("ZIP hard_reset drive=%d\n", c);

            if (zip_drives[c].bus_type == ZIP_BUS_SCSI) {
                scsi_bus = (zip_drives[c].scsi_device_id >> 4) & 0x0f;
                scsi_id  = zip_drives[c].scsi_device_id & 0x0f;

                /* Make sure to ignore any SCSI ZIP drive that has an out of range SCSI bus. */
                if (scsi_bus >= SCSI_BUS_MAX)
                    continue;

                /* Make sure to ignore any SCSI ZIP drive that has an out of range ID. */
                if (scsi_id >= SCSI_ID_MAX)
                    continue;
            }

            /* Make sure to ignore any ATAPI ZIP drive that has an out of range IDE channel. */
            if ((zip_drives[c].bus_type == ZIP_BUS_ATAPI) && (zip_drives[c].ide_channel > 7))
                continue;

            zip_drive_reset(c);

            dev = (zip_t *) zip_drives[c].priv;

            if (dev->tf == NULL)
                continue;

            dev->id  = c;
            dev->drv = &zip_drives[c];

            zip_init(dev);

            if (strlen(zip_drives[c].image_path))
                zip_load(dev, zip_drives[c].image_path);

            zip_mode_sense_load(dev);

            if (zip_drives[c].bus_type == ZIP_BUS_SCSI)
                zip_log("SCSI ZIP drive %i attached to SCSI ID %i\n", c, zip_drives[c].scsi_device_id);
            else if (zip_drives[c].bus_type == ZIP_BUS_ATAPI)
                zip_log("ATAPI ZIP drive %i attached to IDE channel %i\n", c, zip_drives[c].ide_channel);
        }
    }
}

void
zip_close(void)
{
    zip_t  *dev;
    uint8_t scsi_bus;
    uint8_t scsi_id;

    for (uint8_t c = 0; c < ZIP_NUM; c++) {
        if (zip_drives[c].bus_type == ZIP_BUS_SCSI) {
            scsi_bus = (zip_drives[c].scsi_device_id >> 4) & 0x0f;
            scsi_id  = zip_drives[c].scsi_device_id & 0x0f;

            memset(&scsi_devices[scsi_bus][scsi_id], 0x00, sizeof(scsi_device_t));
        }

        dev = (zip_t *) zip_drives[c].priv;

        if (dev) {
            zip_disk_unload(dev);

            if (dev->tf)
                free(dev->tf);

            free(dev);
            zip_drives[c].priv = NULL;
        }
    }
}