qemu/block/raw-win32.c

/*
 * Block driver for RAW files (win32)
 *
 * Copyright (c) 2006 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include "qemu-common.h"
#include "qemu-timer.h"
#include "block_int.h"
#include "module.h"
#include <windows.h>
#include <winioctl.h>

#define FTYPE_FILE 0
#define FTYPE_CD     1
#define FTYPE_HARDDISK 2

typedef struct BDRVRawState {
    HANDLE hfile;
    int type;
    char drive_path[16]; /* format: "d:\" */
} BDRVRawState;

int qemu_ftruncate64(int fd, int64_t length)
{
    LARGE_INTEGER li;
    DWORD dw;
    LONG high;
    HANDLE h;
    BOOL res;

    if ((GetVersion() & 0x80000000UL) && (length >> 32) != 0)
	return -1;

    h = (HANDLE)_get_osfhandle(fd);

    /* get current position, ftruncate do not change position */
    li.HighPart = 0;
    li.LowPart = SetFilePointer (h, 0, &li.HighPart, FILE_CURRENT);
    if (li.LowPart == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
	return -1;
    }

    high = length >> 32;
    dw = SetFilePointer(h, (DWORD) length, &high, FILE_BEGIN);
    if (dw == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
	return -1;
    }
    res = SetEndOfFile(h);

    /* back to old position */
    SetFilePointer(h, li.LowPart, &li.HighPart, FILE_BEGIN);
    return res ? 0 : -1;
}

static int set_sparse(int fd)
{
    DWORD returned;
    return (int) DeviceIoControl((HANDLE)_get_osfhandle(fd), FSCTL_SET_SPARSE,
				 NULL, 0, NULL, 0, &returned, NULL);
}

static void raw_parse_flags(int flags, int *access_flags, DWORD *overlapped)
{
    assert(access_flags != NULL);
    assert(overlapped != NULL);

    if (flags & BDRV_O_RDWR) {
        *access_flags = GENERIC_READ | GENERIC_WRITE;
    } else {
        *access_flags = GENERIC_READ;
    }

    *overlapped = FILE_ATTRIBUTE_NORMAL;
    if (flags & BDRV_O_NOCACHE) {
        *overlapped |= FILE_FLAG_NO_BUFFERING;
    }
}

static int raw_open(BlockDriverState *bs, const char *filename, int flags)
{
    BDRVRawState *s = bs->opaque;
    int access_flags;
    DWORD overlapped;

    s->type = FTYPE_FILE;

    raw_parse_flags(flags, &access_flags, &overlapped);

    s->hfile = CreateFile(filename, access_flags,
                          FILE_SHARE_READ, NULL,
                          OPEN_EXISTING, overlapped, NULL);
    if (s->hfile == INVALID_HANDLE_VALUE) {
        int err = GetLastError();

        if (err == ERROR_ACCESS_DENIED)
            return -EACCES;
        return -1;
    }
    return 0;
}

static int raw_read(BlockDriverState *bs, int64_t sector_num,
                    uint8_t *buf, int nb_sectors)
{
    BDRVRawState *s = bs->opaque;
    OVERLAPPED ov;
    DWORD ret_count;
    int ret;
    int64_t offset = sector_num * 512;
    int count = nb_sectors * 512;

    memset(&ov, 0, sizeof(ov));
    ov.Offset = offset;
    ov.OffsetHigh = offset >> 32;
    ret = ReadFile(s->hfile, buf, count, &ret_count, &ov);
    if (!ret)
        return ret_count;
    if (ret_count == count)
        ret_count = 0;
    return ret_count;
}

static int raw_write(BlockDriverState *bs, int64_t sector_num,
                     const uint8_t *buf, int nb_sectors)
{
    BDRVRawState *s = bs->opaque;
    OVERLAPPED ov;
    DWORD ret_count;
    int ret;
    int64_t offset = sector_num * 512;
    int count = nb_sectors * 512;

    memset(&ov, 0, sizeof(ov));
    ov.Offset = offset;
    ov.OffsetHigh = offset >> 32;
    ret = WriteFile(s->hfile, buf, count, &ret_count, &ov);
    if (!ret)
        return ret_count;
    if (ret_count == count)
        ret_count = 0;
    return ret_count;
}

static int raw_flush(BlockDriverState *bs)
{
    BDRVRawState *s = bs->opaque;
    int ret;

    ret = FlushFileBuffers(s->hfile);
    if (ret == 0) {
        return -EIO;
    }

    return 0;
}

static void raw_close(BlockDriverState *bs)
{
    BDRVRawState *s = bs->opaque;
    CloseHandle(s->hfile);
}

static int raw_truncate(BlockDriverState *bs, int64_t offset)
{
    BDRVRawState *s = bs->opaque;
    LONG low, high;

    low = offset;
    high = offset >> 32;
    if (!SetFilePointer(s->hfile, low, &high, FILE_BEGIN))
	return -EIO;
    if (!SetEndOfFile(s->hfile))
        return -EIO;
    return 0;
}

static int64_t raw_getlength(BlockDriverState *bs)
{
    BDRVRawState *s = bs->opaque;
    LARGE_INTEGER l;
    ULARGE_INTEGER available, total, total_free;
    DISK_GEOMETRY_EX dg;
    DWORD count;
    BOOL status;

    switch(s->type) {
    case FTYPE_FILE:
        l.LowPart = GetFileSize(s->hfile, (PDWORD)&l.HighPart);
        if (l.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
            return -EIO;
        break;
    case FTYPE_CD:
        if (!GetDiskFreeSpaceEx(s->drive_path, &available, &total, &total_free))
            return -EIO;
        l.QuadPart = total.QuadPart;
        break;
    case FTYPE_HARDDISK:
        status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
                                 NULL, 0, &dg, sizeof(dg), &count, NULL);
        if (status != 0) {
            l = dg.DiskSize;
        }
        break;
    default:
        return -EIO;
    }
    return l.QuadPart;
}

static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
{
    typedef DWORD (WINAPI * get_compressed_t)(const char *filename,
                                              DWORD * high);
    get_compressed_t get_compressed;
    struct _stati64 st;
    const char *filename = bs->filename;
    /* WinNT support GetCompressedFileSize to determine allocate size */
    get_compressed =
        (get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"),
                                            "GetCompressedFileSizeA");
    if (get_compressed) {
        DWORD high, low;
        low = get_compressed(filename, &high);
        if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR) {
            return (((int64_t) high) << 32) + low;
        }
    }

    if (_stati64(filename, &st) < 0) {
        return -1;
    }
    return st.st_size;
}

static int raw_create(const char *filename, QEMUOptionParameter *options)
{
    int fd;
    int64_t total_size = 0;

    /* Read out options */
    while (options && options->name) {
        if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
            total_size = options->value.n / 512;
        }
        options++;
    }

    fd = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
                   0644);
    if (fd < 0)
        return -EIO;
    set_sparse(fd);
    ftruncate(fd, total_size * 512);
    qemu_close(fd);
    return 0;
}

static QEMUOptionParameter raw_create_options[] = {
    {
        .name = BLOCK_OPT_SIZE,
        .type = OPT_SIZE,
        .help = "Virtual disk size"
    },
    { NULL }
};

static BlockDriver bdrv_file = {
    .format_name	= "file",
    .protocol_name	= "file",
    .instance_size	= sizeof(BDRVRawState),
    .bdrv_file_open	= raw_open,
    .bdrv_close		= raw_close,
    .bdrv_create	= raw_create,

    .bdrv_read              = raw_read,
    .bdrv_write             = raw_write,
    .bdrv_co_flush_to_disk  = raw_flush,

    .bdrv_truncate	= raw_truncate,
    .bdrv_getlength	= raw_getlength,
    .bdrv_get_allocated_file_size
                        = raw_get_allocated_file_size,

    .create_options = raw_create_options,
};

/***********************************************/
/* host device */

static int find_cdrom(char *cdrom_name, int cdrom_name_size)
{
    char drives[256], *pdrv = drives;
    UINT type;

    memset(drives, 0, sizeof(drives));
    GetLogicalDriveStrings(sizeof(drives), drives);
    while(pdrv[0] != '\0') {
        type = GetDriveType(pdrv);
        switch(type) {
        case DRIVE_CDROM:
            snprintf(cdrom_name, cdrom_name_size, "\\\\.\\%c:", pdrv[0]);
            return 0;
            break;
        }
        pdrv += lstrlen(pdrv) + 1;
    }
    return -1;
}

static int find_device_type(BlockDriverState *bs, const char *filename)
{
    BDRVRawState *s = bs->opaque;
    UINT type;
    const char *p;

    if (strstart(filename, "\\\\.\\", &p) ||
        strstart(filename, "//./", &p)) {
        if (stristart(p, "PhysicalDrive", NULL))
            return FTYPE_HARDDISK;
        snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", p[0]);
        type = GetDriveType(s->drive_path);
        switch (type) {
        case DRIVE_REMOVABLE:
        case DRIVE_FIXED:
            return FTYPE_HARDDISK;
        case DRIVE_CDROM:
            return FTYPE_CD;
        default:
            return FTYPE_FILE;
        }
    } else {
        return FTYPE_FILE;
    }
}

static int hdev_probe_device(const char *filename)
{
    if (strstart(filename, "/dev/cdrom", NULL))
        return 100;
    if (is_windows_drive(filename))
        return 100;
    return 0;
}

static int hdev_open(BlockDriverState *bs, const char *filename, int flags)
{
    BDRVRawState *s = bs->opaque;
    int access_flags, create_flags;
    DWORD overlapped;
    char device_name[64];

    if (strstart(filename, "/dev/cdrom", NULL)) {
        if (find_cdrom(device_name, sizeof(device_name)) < 0)
            return -ENOENT;
        filename = device_name;
    } else {
        /* transform drive letters into device name */
        if (((filename[0] >= 'a' && filename[0] <= 'z') ||
             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
            filename[1] == ':' && filename[2] == '\0') {
            snprintf(device_name, sizeof(device_name), "\\\\.\\%c:", filename[0]);
            filename = device_name;
        }
    }
    s->type = find_device_type(bs, filename);

    raw_parse_flags(flags, &access_flags, &overlapped);

    create_flags = OPEN_EXISTING;

    s->hfile = CreateFile(filename, access_flags,
                          FILE_SHARE_READ, NULL,
                          create_flags, overlapped, NULL);
    if (s->hfile == INVALID_HANDLE_VALUE) {
        int err = GetLastError();

        if (err == ERROR_ACCESS_DENIED)
            return -EACCES;
        return -1;
    }
    return 0;
}

static int hdev_has_zero_init(BlockDriverState *bs)
{
    return 0;
}

static BlockDriver bdrv_host_device = {
    .format_name	= "host_device",
    .protocol_name	= "host_device",
    .instance_size	= sizeof(BDRVRawState),
    .bdrv_probe_device	= hdev_probe_device,
    .bdrv_file_open	= hdev_open,
    .bdrv_close		= raw_close,
    .bdrv_has_zero_init = hdev_has_zero_init,

    .bdrv_read              = raw_read,
    .bdrv_write             = raw_write,
    .bdrv_co_flush_to_disk  = raw_flush,

    .bdrv_getlength	= raw_getlength,
    .bdrv_get_allocated_file_size
                        = raw_get_allocated_file_size,
};

static void bdrv_file_init(void)
{
    bdrv_register(&bdrv_file);
    bdrv_register(&bdrv_host_device);
}

block_init(bdrv_file_init);