block/parallels.c - qemu - Git at Google

 /*
  * 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/block_int.h"
 #include "qemu/module.h"

 /**************************************************************/

 #define HEADER_MAGIC "WithoutFreeSpace"
 #define HEADER_MAGIC2 "WithouFreSpacExt"
 #define HEADER_VERSION 2

 // always little-endian
 typedef struct ParallelsHeader {
     char magic[16]; // "WithoutFreeSpace"
     uint32_t version;
     uint32_t heads;
     uint32_t cylinders;
     uint32_t tracks;
     uint32_t catalog_entries;
     uint64_t nb_sectors;
     uint32_t inuse;
     uint32_t data_off;
     char padding[12];
 } QEMU_PACKED ParallelsHeader;

 typedef struct BDRVParallelsState {
     /** Locking is conservative, the lock protects
      *   - image file extending (truncate, fallocate)
      *   - any access to block allocation table
      */
     CoMutex lock;

     uint32_t *catalog_bitmap;
     unsigned int catalog_size;

     unsigned int tracks;

     unsigned int off_multiplier;

     bool has_truncate;
 } BDRVParallelsState;

 static int parallels_probe(const uint8_t *buf, int buf_size, const char *filename)
 {
     const ParallelsHeader *ph = (const void *)buf;

     if (buf_size < sizeof(ParallelsHeader))
         return 0;

     if ((!memcmp(ph->magic, HEADER_MAGIC, 16) ||
         !memcmp(ph->magic, HEADER_MAGIC2, 16)) &&
         (le32_to_cpu(ph->version) == HEADER_VERSION))
         return 100;

     return 0;
 }

 static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
                           Error **errp)
 {
     BDRVParallelsState *s = bs->opaque;
     int i;
     ParallelsHeader ph;
     int ret;

     ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph));
     if (ret < 0) {
         goto fail;
     }

     bs->total_sectors = le64_to_cpu(ph.nb_sectors);

     if (le32_to_cpu(ph.version) != HEADER_VERSION) {
         goto fail_format;
     }
     if (!memcmp(ph.magic, HEADER_MAGIC, 16)) {
         s->off_multiplier = 1;
         bs->total_sectors = 0xffffffff & bs->total_sectors;
     } else if (!memcmp(ph.magic, HEADER_MAGIC2, 16)) {
         s->off_multiplier = le32_to_cpu(ph.tracks);
     } else {
         goto fail_format;
     }

     s->tracks = le32_to_cpu(ph.tracks);
     if (s->tracks == 0) {
         error_setg(errp, "Invalid image: Zero sectors per track");
         ret = -EINVAL;
         goto fail;
     }
     if (s->tracks > INT32_MAX/513) {
         error_setg(errp, "Invalid image: Too big cluster");
         ret = -EFBIG;
         goto fail;
     }

     s->catalog_size = le32_to_cpu(ph.catalog_entries);
     if (s->catalog_size > INT_MAX / sizeof(uint32_t)) {
         error_setg(errp, "Catalog too large");
         ret = -EFBIG;
         goto fail;
     }
     s->catalog_bitmap = g_try_new(uint32_t, s->catalog_size);
     if (s->catalog_size && s->catalog_bitmap == NULL) {
         ret = -ENOMEM;
         goto fail;
     }

     ret = bdrv_pread(bs->file, sizeof(ParallelsHeader),
                      s->catalog_bitmap, s->catalog_size * sizeof(uint32_t));
     if (ret < 0) {
         goto fail;
     }

     for (i = 0; i < s->catalog_size; i++)
         le32_to_cpus(&s->catalog_bitmap[i]);

     s->has_truncate = bdrv_has_zero_init(bs->file) &&
                       bdrv_truncate(bs->file, bdrv_getlength(bs->file)) == 0;

     qemu_co_mutex_init(&s->lock);
     return 0;

 fail_format:
     error_setg(errp, "Image not in Parallels format");
     ret = -EINVAL;
 fail:
     g_free(s->catalog_bitmap);
     return ret;
 }

 static int64_t seek_to_sector(BDRVParallelsState *s, int64_t sector_num)
 {
     uint32_t index, offset;

     index = sector_num / s->tracks;
     offset = sector_num % s->tracks;

     /* not allocated */
     if ((index >= s->catalog_size) || (s->catalog_bitmap[index] == 0))
         return -1;
     return (uint64_t)s->catalog_bitmap[index] * s->off_multiplier + offset;
 }

 static int cluster_remainder(BDRVParallelsState *s, int64_t sector_num,
         int nb_sectors)
 {
     int ret = s->tracks - sector_num % s->tracks;
     return MIN(nb_sectors, ret);
 }

 static int64_t allocate_cluster(BlockDriverState *bs, int64_t sector_num)
 {
     BDRVParallelsState *s = bs->opaque;
     uint32_t idx, offset, tmp;
     int64_t pos;
     int ret;

     idx = sector_num / s->tracks;
     offset = sector_num % s->tracks;

     if (idx >= s->catalog_size) {
         return -EINVAL;
     }
     if (s->catalog_bitmap[idx] != 0) {
         return (uint64_t)s->catalog_bitmap[idx] * s->off_multiplier + offset;
     }

     pos = bdrv_getlength(bs->file) >> BDRV_SECTOR_BITS;
     if (s->has_truncate) {
         ret = bdrv_truncate(bs->file, (pos + s->tracks) << BDRV_SECTOR_BITS);
     } else {
         ret = bdrv_write_zeroes(bs->file, pos, s->tracks, 0);
     }
     if (ret < 0) {
         return ret;
     }

     s->catalog_bitmap[idx] = pos / s->off_multiplier;

     tmp = cpu_to_le32(s->catalog_bitmap[idx]);

     ret = bdrv_pwrite(bs->file,
             sizeof(ParallelsHeader) + idx * sizeof(tmp), &tmp, sizeof(tmp));
     if (ret < 0) {
         s->catalog_bitmap[idx] = 0;
         return ret;
     }
     return (uint64_t)s->catalog_bitmap[idx] * s->off_multiplier + offset;
 }

 static int64_t coroutine_fn parallels_co_get_block_status(BlockDriverState *bs,
         int64_t sector_num, int nb_sectors, int *pnum)
 {
     BDRVParallelsState *s = bs->opaque;
     int64_t offset;

     qemu_co_mutex_lock(&s->lock);
     offset = seek_to_sector(s, sector_num);
     qemu_co_mutex_unlock(&s->lock);

     *pnum = cluster_remainder(s, sector_num, nb_sectors);

     if (offset < 0) {
         return 0;
     }

     return (offset << BDRV_SECTOR_BITS) |
         BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
 }

 static coroutine_fn int parallels_co_writev(BlockDriverState *bs,
         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
 {
     BDRVParallelsState *s = bs->opaque;
     uint64_t bytes_done = 0;
     QEMUIOVector hd_qiov;
     int ret = 0;

     qemu_iovec_init(&hd_qiov, qiov->niov);

     while (nb_sectors > 0) {
         int64_t position;
         int n, nbytes;

         qemu_co_mutex_lock(&s->lock);
         position = allocate_cluster(bs, sector_num);
         qemu_co_mutex_unlock(&s->lock);
         if (position < 0) {
             ret = (int)position;
             break;
         }

         n = cluster_remainder(s, sector_num, nb_sectors);
         nbytes = n << BDRV_SECTOR_BITS;

         qemu_iovec_reset(&hd_qiov);
         qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);

         ret = bdrv_co_writev(bs->file, position, n, &hd_qiov);
         if (ret < 0) {
             break;
         }

         nb_sectors -= n;
         sector_num += n;
         bytes_done += nbytes;
     }

     qemu_iovec_destroy(&hd_qiov);
     return ret;
 }

 static coroutine_fn int parallels_co_readv(BlockDriverState *bs,
         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
 {
     BDRVParallelsState *s = bs->opaque;
     uint64_t bytes_done = 0;
     QEMUIOVector hd_qiov;
     int ret = 0;

     qemu_iovec_init(&hd_qiov, qiov->niov);

     while (nb_sectors > 0) {
         int64_t position;
         int n, nbytes;

         qemu_co_mutex_lock(&s->lock);
         position = seek_to_sector(s, sector_num);
         qemu_co_mutex_unlock(&s->lock);

         n = cluster_remainder(s, sector_num, nb_sectors);
         nbytes = n << BDRV_SECTOR_BITS;

         if (position < 0) {
             qemu_iovec_memset(qiov, bytes_done, 0, nbytes);
         } else {
             qemu_iovec_reset(&hd_qiov);
             qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);

             ret = bdrv_co_readv(bs->file, position, n, &hd_qiov);
             if (ret < 0) {
                 break;
             }
         }

         nb_sectors -= n;
         sector_num += n;
         bytes_done += nbytes;
     }

     qemu_iovec_destroy(&hd_qiov);
     return ret;
 }

 static void parallels_close(BlockDriverState *bs)
 {
     BDRVParallelsState *s = bs->opaque;
     g_free(s->catalog_bitmap);
 }

 static BlockDriver bdrv_parallels = {
     .format_name	= "parallels",
     .instance_size	= sizeof(BDRVParallelsState),
     .bdrv_probe		= parallels_probe,
     .bdrv_open		= parallels_open,
     .bdrv_close		= parallels_close,
     .bdrv_co_get_block_status = parallels_co_get_block_status,
     .bdrv_has_zero_init       = bdrv_has_zero_init_1,
     .bdrv_co_readv  = parallels_co_readv,
     .bdrv_co_writev = parallels_co_writev,
 };

 static void bdrv_parallels_init(void)
 {
     bdrv_register(&bdrv_parallels);
 }

 block_init(bdrv_parallels_init);
	/*
	* 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/block_int.h"
	#include "qemu/module.h"

	/**************************************************************/

	#define HEADER_MAGIC "WithoutFreeSpace"
	#define HEADER_MAGIC2 "WithouFreSpacExt"
	#define HEADER_VERSION 2

	// always little-endian
	typedef struct ParallelsHeader {
	char magic[16]; // "WithoutFreeSpace"
	uint32_t version;
	uint32_t heads;
	uint32_t cylinders;
	uint32_t tracks;
	uint32_t catalog_entries;
	uint64_t nb_sectors;
	uint32_t inuse;
	uint32_t data_off;
	char padding[12];
	} QEMU_PACKED ParallelsHeader;

	typedef struct BDRVParallelsState {
	/** Locking is conservative, the lock protects
	* - image file extending (truncate, fallocate)
	* - any access to block allocation table
	*/
	CoMutex lock;

	uint32_t *catalog_bitmap;
	unsigned int catalog_size;

	unsigned int tracks;

	unsigned int off_multiplier;

	bool has_truncate;
	} BDRVParallelsState;

	static int parallels_probe(const uint8_t buf, int buf_size, const char filename)
	{
	const ParallelsHeader ph = (const void )buf;

	if (buf_size < sizeof(ParallelsHeader))
	return 0;

	if ((!memcmp(ph->magic, HEADER_MAGIC, 16) \|\|
	!memcmp(ph->magic, HEADER_MAGIC2, 16)) &&
	(le32_to_cpu(ph->version) == HEADER_VERSION))
	return 100;

	return 0;
	}

	static int parallels_open(BlockDriverState bs, QDict options, int flags,
	Error **errp)
	{
	BDRVParallelsState *s = bs->opaque;
	int i;
	ParallelsHeader ph;
	int ret;

	ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph));
	if (ret < 0) {
	goto fail;
	}

	bs->total_sectors = le64_to_cpu(ph.nb_sectors);

	if (le32_to_cpu(ph.version) != HEADER_VERSION) {
	goto fail_format;
	}
	if (!memcmp(ph.magic, HEADER_MAGIC, 16)) {
	s->off_multiplier = 1;
	bs->total_sectors = 0xffffffff & bs->total_sectors;
	} else if (!memcmp(ph.magic, HEADER_MAGIC2, 16)) {
	s->off_multiplier = le32_to_cpu(ph.tracks);
	} else {
	goto fail_format;
	}

	s->tracks = le32_to_cpu(ph.tracks);
	if (s->tracks == 0) {
	error_setg(errp, "Invalid image: Zero sectors per track");
	ret = -EINVAL;
	goto fail;
	}
	if (s->tracks > INT32_MAX/513) {
	error_setg(errp, "Invalid image: Too big cluster");
	ret = -EFBIG;
	goto fail;
	}

	s->catalog_size = le32_to_cpu(ph.catalog_entries);
	if (s->catalog_size > INT_MAX / sizeof(uint32_t)) {
	error_setg(errp, "Catalog too large");
	ret = -EFBIG;
	goto fail;
	}
	s->catalog_bitmap = g_try_new(uint32_t, s->catalog_size);
	if (s->catalog_size && s->catalog_bitmap == NULL) {
	ret = -ENOMEM;
	goto fail;
	}

	ret = bdrv_pread(bs->file, sizeof(ParallelsHeader),
	s->catalog_bitmap, s->catalog_size * sizeof(uint32_t));
	if (ret < 0) {
	goto fail;
	}

	for (i = 0; i < s->catalog_size; i++)
	le32_to_cpus(&s->catalog_bitmap[i]);

	s->has_truncate = bdrv_has_zero_init(bs->file) &&
	bdrv_truncate(bs->file, bdrv_getlength(bs->file)) == 0;

	qemu_co_mutex_init(&s->lock);
	return 0;

	fail_format:
	error_setg(errp, "Image not in Parallels format");
	ret = -EINVAL;
	fail:
	g_free(s->catalog_bitmap);
	return ret;
	}

	static int64_t seek_to_sector(BDRVParallelsState *s, int64_t sector_num)
	{
	uint32_t index, offset;

	index = sector_num / s->tracks;
	offset = sector_num % s->tracks;

	/* not allocated */
	if ((index >= s->catalog_size) \|\| (s->catalog_bitmap[index] == 0))
	return -1;
	return (uint64_t)s->catalog_bitmap[index] * s->off_multiplier + offset;
	}

	static int cluster_remainder(BDRVParallelsState *s, int64_t sector_num,
	int nb_sectors)
	{
	int ret = s->tracks - sector_num % s->tracks;
	return MIN(nb_sectors, ret);
	}

	static int64_t allocate_cluster(BlockDriverState *bs, int64_t sector_num)
	{
	BDRVParallelsState *s = bs->opaque;
	uint32_t idx, offset, tmp;
	int64_t pos;
	int ret;

	idx = sector_num / s->tracks;
	offset = sector_num % s->tracks;

	if (idx >= s->catalog_size) {
	return -EINVAL;
	}
	if (s->catalog_bitmap[idx] != 0) {
	return (uint64_t)s->catalog_bitmap[idx] * s->off_multiplier + offset;
	}

	pos = bdrv_getlength(bs->file) >> BDRV_SECTOR_BITS;
	if (s->has_truncate) {
	ret = bdrv_truncate(bs->file, (pos + s->tracks) << BDRV_SECTOR_BITS);
	} else {
	ret = bdrv_write_zeroes(bs->file, pos, s->tracks, 0);
	}
	if (ret < 0) {
	return ret;
	}

	s->catalog_bitmap[idx] = pos / s->off_multiplier;

	tmp = cpu_to_le32(s->catalog_bitmap[idx]);

	ret = bdrv_pwrite(bs->file,
	sizeof(ParallelsHeader) + idx * sizeof(tmp), &tmp, sizeof(tmp));
	if (ret < 0) {
	s->catalog_bitmap[idx] = 0;
	return ret;
	}
	return (uint64_t)s->catalog_bitmap[idx] * s->off_multiplier + offset;
	}

	static int64_t coroutine_fn parallels_co_get_block_status(BlockDriverState *bs,
	int64_t sector_num, int nb_sectors, int *pnum)
	{
	BDRVParallelsState *s = bs->opaque;
	int64_t offset;

	qemu_co_mutex_lock(&s->lock);
	offset = seek_to_sector(s, sector_num);
	qemu_co_mutex_unlock(&s->lock);

	*pnum = cluster_remainder(s, sector_num, nb_sectors);

	if (offset < 0) {
	return 0;
	}

	return (offset << BDRV_SECTOR_BITS) \|
	BDRV_BLOCK_DATA \| BDRV_BLOCK_OFFSET_VALID;
	}

	static coroutine_fn int parallels_co_writev(BlockDriverState *bs,
	int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
	{
	BDRVParallelsState *s = bs->opaque;
	uint64_t bytes_done = 0;
	QEMUIOVector hd_qiov;
	int ret = 0;

	qemu_iovec_init(&hd_qiov, qiov->niov);

	while (nb_sectors > 0) {
	int64_t position;
	int n, nbytes;

	qemu_co_mutex_lock(&s->lock);
	position = allocate_cluster(bs, sector_num);
	qemu_co_mutex_unlock(&s->lock);
	if (position < 0) {
	ret = (int)position;
	break;
	}

	n = cluster_remainder(s, sector_num, nb_sectors);
	nbytes = n << BDRV_SECTOR_BITS;

	qemu_iovec_reset(&hd_qiov);
	qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);

	ret = bdrv_co_writev(bs->file, position, n, &hd_qiov);
	if (ret < 0) {
	break;
	}

	nb_sectors -= n;
	sector_num += n;
	bytes_done += nbytes;
	}

	qemu_iovec_destroy(&hd_qiov);
	return ret;
	}

	static coroutine_fn int parallels_co_readv(BlockDriverState *bs,
	int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
	{
	BDRVParallelsState *s = bs->opaque;
	uint64_t bytes_done = 0;
	QEMUIOVector hd_qiov;
	int ret = 0;

	qemu_iovec_init(&hd_qiov, qiov->niov);

	while (nb_sectors > 0) {
	int64_t position;
	int n, nbytes;

	qemu_co_mutex_lock(&s->lock);
	position = seek_to_sector(s, sector_num);
	qemu_co_mutex_unlock(&s->lock);

	n = cluster_remainder(s, sector_num, nb_sectors);
	nbytes = n << BDRV_SECTOR_BITS;

	if (position < 0) {
	qemu_iovec_memset(qiov, bytes_done, 0, nbytes);
	} else {
	qemu_iovec_reset(&hd_qiov);
	qemu_iovec_concat(&hd_qiov, qiov, bytes_done, nbytes);

	ret = bdrv_co_readv(bs->file, position, n, &hd_qiov);
	if (ret < 0) {
	break;
	}
	}

	nb_sectors -= n;
	sector_num += n;
	bytes_done += nbytes;
	}

	qemu_iovec_destroy(&hd_qiov);
	return ret;
	}

	static void parallels_close(BlockDriverState *bs)
	{
	BDRVParallelsState *s = bs->opaque;
	g_free(s->catalog_bitmap);
	}

	static BlockDriver bdrv_parallels = {
	.format_name = "parallels",
	.instance_size = sizeof(BDRVParallelsState),
	.bdrv_probe = parallels_probe,
	.bdrv_open = parallels_open,
	.bdrv_close = parallels_close,
	.bdrv_co_get_block_status = parallels_co_get_block_status,
	.bdrv_has_zero_init = bdrv_has_zero_init_1,
	.bdrv_co_readv = parallels_co_readv,
	.bdrv_co_writev = parallels_co_writev,
	};

	static void bdrv_parallels_init(void)
	{
	bdrv_register(&bdrv_parallels);
	}

	block_init(bdrv_parallels_init);