qemu-e2k/block-parallels.c

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/*
* Block driver for Parallels disk image format
*
* Copyright (c) 2007 Alex Beregszaszi
*
* This code is based on comparing different disk images created by Parallels.
*
* 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 "block_int.h"
/**************************************************************/
#define HEADER_MAGIC "WithoutFreeSpace"
#define HEADER_VERSION 2
#define HEADER_SIZE 64
// always little-endian
struct parallels_header {
char magic[16]; // "WithoutFreeSpace"
uint32_t version;
uint32_t heads;
uint32_t cylinders;
uint32_t tracks;
uint32_t catalog_entries;
uint32_t nb_sectors;
char padding[24];
} __attribute__((packed));
typedef struct BDRVParallelsState {
int fd;
uint32_t *catalog_bitmap;
int catalog_size;
int tracks;
} BDRVParallelsState;
static int parallels_probe(const uint8_t *buf, int buf_size, const char *filename)
{
const struct parallels_header *ph = (const void *)buf;
if (buf_size < HEADER_SIZE)
return 0;
if (!memcmp(ph->magic, HEADER_MAGIC, 16) &&
(le32_to_cpu(ph->version) == HEADER_VERSION))
return 100;
return 0;
}
static int parallels_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVParallelsState *s = bs->opaque;
int fd, i;
struct parallels_header ph;
fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE);
if (fd < 0) {
fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
if (fd < 0)
return -1;
}
bs->read_only = 1; // no write support yet
s->fd = fd;
if (read(fd, &ph, sizeof(ph)) != sizeof(ph))
goto fail;
if (memcmp(ph.magic, HEADER_MAGIC, 16) ||
(le32_to_cpu(ph.version) != HEADER_VERSION)) {
goto fail;
}
bs->total_sectors = le32_to_cpu(ph.nb_sectors);
if (lseek(s->fd, 64, SEEK_SET) != 64)
goto fail;
s->tracks = le32_to_cpu(ph.tracks);
s->catalog_size = le32_to_cpu(ph.catalog_entries);
s->catalog_bitmap = qemu_malloc(s->catalog_size * 4);
if (read(s->fd, s->catalog_bitmap, s->catalog_size * 4) !=
s->catalog_size * 4)
goto fail;
for (i = 0; i < s->catalog_size; i++)
le32_to_cpus(&s->catalog_bitmap[i]);
return 0;
fail:
if (s->catalog_bitmap)
qemu_free(s->catalog_bitmap);
close(fd);
return -1;
}
static inline int seek_to_sector(BlockDriverState *bs, int64_t sector_num)
{
BDRVParallelsState *s = bs->opaque;
uint32_t index, offset, position;
index = sector_num / s->tracks;
offset = sector_num % s->tracks;
// not allocated
if ((index > s->catalog_size) || (s->catalog_bitmap[index] == 0))
return -1;
position = (s->catalog_bitmap[index] + offset) * 512;
// fprintf(stderr, "sector: %llx index=%x offset=%x pointer=%x position=%x\n",
// sector_num, index, offset, s->catalog_bitmap[index], position);
if (lseek(s->fd, position, SEEK_SET) != position)
return -1;
return 0;
}
static int parallels_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
BDRVParallelsState *s = bs->opaque;
while (nb_sectors > 0) {
if (!seek_to_sector(bs, sector_num)) {
if (read(s->fd, buf, 512) != 512)
return -1;
} else
memset(buf, 0, 512);
nb_sectors--;
sector_num++;
buf += 512;
}
return 0;
}
static void parallels_close(BlockDriverState *bs)
{
BDRVParallelsState *s = bs->opaque;
qemu_free(s->catalog_bitmap);
close(s->fd);
}
BlockDriver bdrv_parallels = {
.format_name = "parallels",
.instance_size = sizeof(BDRVParallelsState),
.bdrv_probe = parallels_probe,
.bdrv_open = parallels_open,
.bdrv_read = parallels_read,
.bdrv_close = parallels_close,
};