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qemu/block/vmdk.c
Kevin Wolf 66f82ceed6 block: Open the underlying image file in generic code 
Format drivers shouldn't need to bother with things like file names, but rather
just get an open BlockDriverState for the underlying protocol. This patch
introduces this behaviour for bdrv_open implementation. For protocols which
need to access the filename to open their file/device/connection/... a new
callback bdrv_file_open is introduced which doesn't get an underlying file
opened.

For now, also some of the more obscure formats use bdrv_file_open because they
open() the file themselves instead of using the block.c functions. They need to
be fixed in later patches.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:30 +02:00

934 lines
27 KiB
C
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/*
* Block driver for the VMDK format
*
* Copyright (c) 2004 Fabrice Bellard
* Copyright (c) 2005 Filip Navara
*
* 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"
#include "module.h"
#define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D')
#define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V')
typedef struct {
uint32_t version;
uint32_t flags;
uint32_t disk_sectors;
uint32_t granularity;
uint32_t l1dir_offset;
uint32_t l1dir_size;
uint32_t file_sectors;
uint32_t cylinders;
uint32_t heads;
uint32_t sectors_per_track;
} VMDK3Header;
typedef struct {
uint32_t version;
uint32_t flags;
int64_t capacity;
int64_t granularity;
int64_t desc_offset;
int64_t desc_size;
int32_t num_gtes_per_gte;
int64_t rgd_offset;
int64_t gd_offset;
int64_t grain_offset;
char filler[1];
char check_bytes[4];
} __attribute__((packed)) VMDK4Header;
#define L2_CACHE_SIZE 16
typedef struct BDRVVmdkState {
BlockDriverState *hd;
int64_t l1_table_offset;
int64_t l1_backup_table_offset;
uint32_t *l1_table;
uint32_t *l1_backup_table;
unsigned int l1_size;
uint32_t l1_entry_sectors;
unsigned int l2_size;
uint32_t *l2_cache;
uint32_t l2_cache_offsets[L2_CACHE_SIZE];
uint32_t l2_cache_counts[L2_CACHE_SIZE];
unsigned int cluster_sectors;
uint32_t parent_cid;
int is_parent;
} BDRVVmdkState;
typedef struct VmdkMetaData {
uint32_t offset;
unsigned int l1_index;
unsigned int l2_index;
unsigned int l2_offset;
int valid;
} VmdkMetaData;
typedef struct ActiveBDRVState{
BlockDriverState *hd; // active image handler
uint64_t cluster_offset; // current write offset
}ActiveBDRVState;
static ActiveBDRVState activeBDRV;
static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename)
{
uint32_t magic;
if (buf_size < 4)
return 0;
magic = be32_to_cpu(*(uint32_t *)buf);
if (magic == VMDK3_MAGIC ||
magic == VMDK4_MAGIC)
return 100;
else
return 0;
}
#define CHECK_CID 1
#define SECTOR_SIZE 512
#define DESC_SIZE 20*SECTOR_SIZE // 20 sectors of 512 bytes each
#define HEADER_SIZE 512 // first sector of 512 bytes
static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent)
{
BDRVVmdkState *s = bs->opaque;
char desc[DESC_SIZE];
uint32_t cid;
const char *p_name, *cid_str;
size_t cid_str_size;
/* the descriptor offset = 0x200 */
if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
return 0;
if (parent) {
cid_str = "parentCID";
cid_str_size = sizeof("parentCID");
} else {
cid_str = "CID";
cid_str_size = sizeof("CID");
}
if ((p_name = strstr(desc,cid_str)) != NULL) {
p_name += cid_str_size;
sscanf(p_name,"%x",&cid);
}
return cid;
}
static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
{
BDRVVmdkState *s = bs->opaque;
char desc[DESC_SIZE], tmp_desc[DESC_SIZE];
char *p_name, *tmp_str;
/* the descriptor offset = 0x200 */
if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
return -1;
tmp_str = strstr(desc,"parentCID");
pstrcpy(tmp_desc, sizeof(tmp_desc), tmp_str);
if ((p_name = strstr(desc,"CID")) != NULL) {
p_name += sizeof("CID");
snprintf(p_name, sizeof(desc) - (p_name - desc), "%x\n", cid);
pstrcat(desc, sizeof(desc), tmp_desc);
}
if (bdrv_pwrite(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
return -1;
return 0;
}
static int vmdk_is_cid_valid(BlockDriverState *bs)
{
#ifdef CHECK_CID
BDRVVmdkState *s = bs->opaque;
BlockDriverState *p_bs = bs->backing_hd;
uint32_t cur_pcid;
if (p_bs) {
cur_pcid = vmdk_read_cid(p_bs,0);
if (s->parent_cid != cur_pcid)
// CID not valid
return 0;
}
#endif
// CID valid
return 1;
}
static int vmdk_snapshot_create(const char *filename, const char *backing_file)
{
int snp_fd, p_fd;
int ret;
uint32_t p_cid;
char *p_name, *gd_buf, *rgd_buf;
const char *real_filename, *temp_str;
VMDK4Header header;
uint32_t gde_entries, gd_size;
int64_t gd_offset, rgd_offset, capacity, gt_size;
char p_desc[DESC_SIZE], s_desc[DESC_SIZE], hdr[HEADER_SIZE];
static const char desc_template[] =
"# Disk DescriptorFile\n"
"version=1\n"
"CID=%x\n"
"parentCID=%x\n"
"createType=\"monolithicSparse\"\n"
"parentFileNameHint=\"%s\"\n"
"\n"
"# Extent description\n"
"RW %u SPARSE \"%s\"\n"
"\n"
"# The Disk Data Base \n"
"#DDB\n"
"\n";
snp_fd = open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, 0644);
if (snp_fd < 0)
return -errno;
p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE);
if (p_fd < 0) {
close(snp_fd);
return -errno;
}
/* read the header */
if (lseek(p_fd, 0x0, SEEK_SET) == -1) {
ret = -errno;
goto fail;
}
if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE) {
ret = -errno;
goto fail;
}
/* write the header */
if (lseek(snp_fd, 0x0, SEEK_SET) == -1) {
ret = -errno;
goto fail;
}
if (write(snp_fd, hdr, HEADER_SIZE) == -1) {
ret = -errno;
goto fail;
}
memset(&header, 0, sizeof(header));
memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC
if (ftruncate(snp_fd, header.grain_offset << 9)) {
ret = -errno;
goto fail;
}
/* the descriptor offset = 0x200 */
if (lseek(p_fd, 0x200, SEEK_SET) == -1) {
ret = -errno;
goto fail;
}
if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE) {
ret = -errno;
goto fail;
}
if ((p_name = strstr(p_desc,"CID")) != NULL) {
p_name += sizeof("CID");
sscanf(p_name,"%x",&p_cid);
}
real_filename = filename;
if ((temp_str = strrchr(real_filename, '\\')) != NULL)
real_filename = temp_str + 1;
if ((temp_str = strrchr(real_filename, '/')) != NULL)
real_filename = temp_str + 1;
if ((temp_str = strrchr(real_filename, ':')) != NULL)
real_filename = temp_str + 1;
snprintf(s_desc, sizeof(s_desc), desc_template, p_cid, p_cid, backing_file,
(uint32_t)header.capacity, real_filename);
/* write the descriptor */
if (lseek(snp_fd, 0x200, SEEK_SET) == -1) {
ret = -errno;
goto fail;
}
if (write(snp_fd, s_desc, strlen(s_desc)) == -1) {
ret = -errno;
goto fail;
}
gd_offset = header.gd_offset * SECTOR_SIZE; // offset of GD table
rgd_offset = header.rgd_offset * SECTOR_SIZE; // offset of RGD table
capacity = header.capacity * SECTOR_SIZE; // Extent size
/*
* Each GDE span 32M disk, means:
* 512 GTE per GT, each GTE points to grain
*/
gt_size = (int64_t)header.num_gtes_per_gte * header.granularity * SECTOR_SIZE;
if (!gt_size) {
ret = -EINVAL;
goto fail;
}
gde_entries = (uint32_t)(capacity / gt_size); // number of gde/rgde
gd_size = gde_entries * sizeof(uint32_t);
/* write RGD */
rgd_buf = qemu_malloc(gd_size);
if (lseek(p_fd, rgd_offset, SEEK_SET) == -1) {
ret = -errno;
goto fail_rgd;
}
if (read(p_fd, rgd_buf, gd_size) != gd_size) {
ret = -errno;
goto fail_rgd;
}
if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1) {
ret = -errno;
goto fail_rgd;
}
if (write(snp_fd, rgd_buf, gd_size) == -1) {
ret = -errno;
goto fail_rgd;
}
/* write GD */
gd_buf = qemu_malloc(gd_size);
if (lseek(p_fd, gd_offset, SEEK_SET) == -1) {
ret = -errno;
goto fail_gd;
}
if (read(p_fd, gd_buf, gd_size) != gd_size) {
ret = -errno;
goto fail_gd;
}
if (lseek(snp_fd, gd_offset, SEEK_SET) == -1) {
ret = -errno;
goto fail_gd;
}
if (write(snp_fd, gd_buf, gd_size) == -1) {
ret = -errno;
goto fail_gd;
}
ret = 0;
fail_gd:
qemu_free(gd_buf);
fail_rgd:
qemu_free(rgd_buf);
fail:
close(p_fd);
close(snp_fd);
return ret;
}
static void vmdk_parent_close(BlockDriverState *bs)
{
if (bs->backing_hd)
bdrv_close(bs->backing_hd);
}
static int parent_open = 0;
static int vmdk_parent_open(BlockDriverState *bs, const char * filename)
{
BDRVVmdkState *s = bs->opaque;
char *p_name;
char desc[DESC_SIZE];
char parent_img_name[1024];
/* the descriptor offset = 0x200 */
if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
return -1;
if ((p_name = strstr(desc,"parentFileNameHint")) != NULL) {
char *end_name;
struct stat file_buf;
p_name += sizeof("parentFileNameHint") + 1;
if ((end_name = strchr(p_name,'\"')) == NULL)
return -1;
if ((end_name - p_name) > sizeof (bs->backing_file) - 1)
return -1;
pstrcpy(bs->backing_file, end_name - p_name + 1, p_name);
if (stat(bs->backing_file, &file_buf) != 0) {
path_combine(parent_img_name, sizeof(parent_img_name),
filename, bs->backing_file);
} else {
pstrcpy(parent_img_name, sizeof(parent_img_name),
bs->backing_file);
}
bs->backing_hd = bdrv_new("");
if (!bs->backing_hd) {
failure:
bdrv_close(s->hd);
return -1;
}
parent_open = 1;
if (bdrv_open(bs->backing_hd, parent_img_name, 0, NULL) < 0)
goto failure;
parent_open = 0;
}
return 0;
}
static int vmdk_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVVmdkState *s = bs->opaque;
uint32_t magic;
int l1_size, i, ret;
if (parent_open) {
/* Parent must be opened as RO, no RDWR. */
flags = 0;
}
ret = bdrv_file_open(&s->hd, filename, flags);
if (ret < 0)
return ret;
if (bdrv_pread(s->hd, 0, &magic, sizeof(magic)) != sizeof(magic))
goto fail;
magic = be32_to_cpu(magic);
if (magic == VMDK3_MAGIC) {
VMDK3Header header;
if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
goto fail;
s->cluster_sectors = le32_to_cpu(header.granularity);
s->l2_size = 1 << 9;
s->l1_size = 1 << 6;
bs->total_sectors = le32_to_cpu(header.disk_sectors);
s->l1_table_offset = le32_to_cpu(header.l1dir_offset) << 9;
s->l1_backup_table_offset = 0;
s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
} else if (magic == VMDK4_MAGIC) {
VMDK4Header header;
if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
goto fail;
bs->total_sectors = le64_to_cpu(header.capacity);
s->cluster_sectors = le64_to_cpu(header.granularity);
s->l2_size = le32_to_cpu(header.num_gtes_per_gte);
s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
if (s->l1_entry_sectors <= 0)
goto fail;
s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1)
/ s->l1_entry_sectors;
s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9;
s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
if (parent_open)
s->is_parent = 1;
else
s->is_parent = 0;
// try to open parent images, if exist
if (vmdk_parent_open(bs, filename) != 0)
goto fail;
// write the CID once after the image creation
s->parent_cid = vmdk_read_cid(bs,1);
} else {
goto fail;
}
/* read the L1 table */
l1_size = s->l1_size * sizeof(uint32_t);
s->l1_table = qemu_malloc(l1_size);
if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, l1_size) != l1_size)
goto fail;
for(i = 0; i < s->l1_size; i++) {
le32_to_cpus(&s->l1_table[i]);
}
if (s->l1_backup_table_offset) {
s->l1_backup_table = qemu_malloc(l1_size);
if (bdrv_pread(s->hd, s->l1_backup_table_offset, s->l1_backup_table, l1_size) != l1_size)
goto fail;
for(i = 0; i < s->l1_size; i++) {
le32_to_cpus(&s->l1_backup_table[i]);
}
}
s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t));
return 0;
fail:
qemu_free(s->l1_backup_table);
qemu_free(s->l1_table);
qemu_free(s->l2_cache);
bdrv_delete(s->hd);
return -1;
}
static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
uint64_t offset, int allocate);
static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset,
uint64_t offset, int allocate)
{
uint64_t parent_cluster_offset;
BDRVVmdkState *s = bs->opaque;
uint8_t whole_grain[s->cluster_sectors*512]; // 128 sectors * 512 bytes each = grain size 64KB
// we will be here if it's first write on non-exist grain(cluster).
// try to read from parent image, if exist
if (bs->backing_hd) {
BDRVVmdkState *ps = bs->backing_hd->opaque;
if (!vmdk_is_cid_valid(bs))
return -1;
parent_cluster_offset = get_cluster_offset(bs->backing_hd, NULL,
offset, allocate);
if (parent_cluster_offset) {
BDRVVmdkState *act_s = activeBDRV.hd->opaque;
if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) != ps->cluster_sectors*512)
return -1;
//Write grain only into the active image
if (bdrv_pwrite(act_s->hd, activeBDRV.cluster_offset << 9, whole_grain, sizeof(whole_grain)) != sizeof(whole_grain))
return -1;
}
}
return 0;
}
static int vmdk_L2update(BlockDriverState *bs, VmdkMetaData *m_data)
{
BDRVVmdkState *s = bs->opaque;
/* update L2 table */
if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)),
&(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset))
return -1;
/* update backup L2 table */
if (s->l1_backup_table_offset != 0) {
m_data->l2_offset = s->l1_backup_table[m_data->l1_index];
if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)),
&(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset))
return -1;
}
return 0;
}
static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
uint64_t offset, int allocate)
{
BDRVVmdkState *s = bs->opaque;
unsigned int l1_index, l2_offset, l2_index;
int min_index, i, j;
uint32_t min_count, *l2_table, tmp = 0;
uint64_t cluster_offset;
if (m_data)
m_data->valid = 0;
l1_index = (offset >> 9) / s->l1_entry_sectors;
if (l1_index >= s->l1_size)
return 0;
l2_offset = s->l1_table[l1_index];
if (!l2_offset)
return 0;
for(i = 0; i < L2_CACHE_SIZE; i++) {
if (l2_offset == s->l2_cache_offsets[i]) {
/* increment the hit count */
if (++s->l2_cache_counts[i] == 0xffffffff) {
for(j = 0; j < L2_CACHE_SIZE; j++) {
s->l2_cache_counts[j] >>= 1;
}
}
l2_table = s->l2_cache + (i * s->l2_size);
goto found;
}
}
/* not found: load a new entry in the least used one */
min_index = 0;
min_count = 0xffffffff;
for(i = 0; i < L2_CACHE_SIZE; i++) {
if (s->l2_cache_counts[i] < min_count) {
min_count = s->l2_cache_counts[i];
min_index = i;
}
}
l2_table = s->l2_cache + (min_index * s->l2_size);
if (bdrv_pread(s->hd, (int64_t)l2_offset * 512, l2_table, s->l2_size * sizeof(uint32_t)) !=
s->l2_size * sizeof(uint32_t))
return 0;
s->l2_cache_offsets[min_index] = l2_offset;
s->l2_cache_counts[min_index] = 1;
found:
l2_index = ((offset >> 9) / s->cluster_sectors) % s->l2_size;
cluster_offset = le32_to_cpu(l2_table[l2_index]);
if (!cluster_offset) {
if (!allocate)
return 0;
// Avoid the L2 tables update for the images that have snapshots.
if (!s->is_parent) {
cluster_offset = bdrv_getlength(s->hd);
bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9));
cluster_offset >>= 9;
tmp = cpu_to_le32(cluster_offset);
l2_table[l2_index] = tmp;
// Save the active image state
activeBDRV.cluster_offset = cluster_offset;
activeBDRV.hd = bs;
}
/* First of all we write grain itself, to avoid race condition
* that may to corrupt the image.
* This problem may occur because of insufficient space on host disk
* or inappropriate VM shutdown.
*/
if (get_whole_cluster(bs, cluster_offset, offset, allocate) == -1)
return 0;
if (m_data) {
m_data->offset = tmp;
m_data->l1_index = l1_index;
m_data->l2_index = l2_index;
m_data->l2_offset = l2_offset;
m_data->valid = 1;
}
}
cluster_offset <<= 9;
return cluster_offset;
}
static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, int *pnum)
{
BDRVVmdkState *s = bs->opaque;
int index_in_cluster, n;
uint64_t cluster_offset;
cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0);
index_in_cluster = sector_num % s->cluster_sectors;
n = s->cluster_sectors - index_in_cluster;
if (n > nb_sectors)
n = nb_sectors;
*pnum = n;
return (cluster_offset != 0);
}
static int vmdk_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
BDRVVmdkState *s = bs->opaque;
int index_in_cluster, n, ret;
uint64_t cluster_offset;
while (nb_sectors > 0) {
cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0);
index_in_cluster = sector_num % s->cluster_sectors;
n = s->cluster_sectors - index_in_cluster;
if (n > nb_sectors)
n = nb_sectors;
if (!cluster_offset) {
// try to read from parent image, if exist
if (bs->backing_hd) {
if (!vmdk_is_cid_valid(bs))
return -1;
ret = bdrv_read(bs->backing_hd, sector_num, buf, n);
if (ret < 0)
return -1;
} else {
memset(buf, 0, 512 * n);
}
} else {
if(bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
return -1;
}
nb_sectors -= n;
sector_num += n;
buf += n * 512;
}
return 0;
}
static int vmdk_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
BDRVVmdkState *s = bs->opaque;
VmdkMetaData m_data;
int index_in_cluster, n;
uint64_t cluster_offset;
static int cid_update = 0;
if (sector_num > bs->total_sectors) {
fprintf(stderr,
"(VMDK) Wrong offset: sector_num=0x%" PRIx64
" total_sectors=0x%" PRIx64 "\n",
sector_num, bs->total_sectors);
return -1;
}
while (nb_sectors > 0) {
index_in_cluster = sector_num & (s->cluster_sectors - 1);
n = s->cluster_sectors - index_in_cluster;
if (n > nb_sectors)
n = nb_sectors;
cluster_offset = get_cluster_offset(bs, &m_data, sector_num << 9, 1);
if (!cluster_offset)
return -1;
if (bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
return -1;
if (m_data.valid) {
/* update L2 tables */
if (vmdk_L2update(bs, &m_data) == -1)
return -1;
}
nb_sectors -= n;
sector_num += n;
buf += n * 512;
// update CID on the first write every time the virtual disk is opened
if (!cid_update) {
vmdk_write_cid(bs, time(NULL));
cid_update++;
}
}
return 0;
}
static int vmdk_create(const char *filename, QEMUOptionParameter *options)
{
int fd, i;
VMDK4Header header;
uint32_t tmp, magic, grains, gd_size, gt_size, gt_count;
static const char desc_template[] =
"# Disk DescriptorFile\n"
"version=1\n"
"CID=%x\n"
"parentCID=ffffffff\n"
"createType=\"monolithicSparse\"\n"
"\n"
"# Extent description\n"
"RW %" PRId64 " SPARSE \"%s\"\n"
"\n"
"# The Disk Data Base \n"
"#DDB\n"
"\n"
"ddb.virtualHWVersion = \"%d\"\n"
"ddb.geometry.cylinders = \"%" PRId64 "\"\n"
"ddb.geometry.heads = \"16\"\n"
"ddb.geometry.sectors = \"63\"\n"
"ddb.adapterType = \"ide\"\n";
char desc[1024];
const char *real_filename, *temp_str;
int64_t total_size = 0;
const char *backing_file = NULL;
int flags = 0;
int ret;
// Read out options
while (options && options->name) {
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
total_size = options->value.n / 512;
} else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
backing_file = options->value.s;
} else if (!strcmp(options->name, BLOCK_OPT_COMPAT6)) {
flags |= options->value.n ? BLOCK_FLAG_COMPAT6: 0;
}
options++;
}
/* XXX: add support for backing file */
if (backing_file) {
return vmdk_snapshot_create(filename, backing_file);
}
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE,
0644);
if (fd < 0)
return -errno;
magic = cpu_to_be32(VMDK4_MAGIC);
memset(&header, 0, sizeof(header));
header.version = cpu_to_le32(1);
header.flags = cpu_to_le32(3); /* ?? */
header.capacity = cpu_to_le64(total_size);
header.granularity = cpu_to_le64(128);
header.num_gtes_per_gte = cpu_to_le32(512);
grains = (total_size + header.granularity - 1) / header.granularity;
gt_size = ((header.num_gtes_per_gte * sizeof(uint32_t)) + 511) >> 9;
gt_count = (grains + header.num_gtes_per_gte - 1) / header.num_gtes_per_gte;
gd_size = (gt_count * sizeof(uint32_t) + 511) >> 9;
header.desc_offset = 1;
header.desc_size = 20;
header.rgd_offset = header.desc_offset + header.desc_size;
header.gd_offset = header.rgd_offset + gd_size + (gt_size * gt_count);
header.grain_offset =
((header.gd_offset + gd_size + (gt_size * gt_count) +
header.granularity - 1) / header.granularity) *
header.granularity;
header.desc_offset = cpu_to_le64(header.desc_offset);
header.desc_size = cpu_to_le64(header.desc_size);
header.rgd_offset = cpu_to_le64(header.rgd_offset);
header.gd_offset = cpu_to_le64(header.gd_offset);
header.grain_offset = cpu_to_le64(header.grain_offset);
header.check_bytes[0] = 0xa;
header.check_bytes[1] = 0x20;
header.check_bytes[2] = 0xd;
header.check_bytes[3] = 0xa;
/* write all the data */
ret = qemu_write_full(fd, &magic, sizeof(magic));
if (ret != sizeof(magic)) {
ret = -errno;
goto exit;
}
ret = qemu_write_full(fd, &header, sizeof(header));
if (ret != sizeof(header)) {
ret = -errno;
goto exit;
}
ret = ftruncate(fd, header.grain_offset << 9);
if (ret < 0) {
ret = -errno;
goto exit;
}
/* write grain directory */
lseek(fd, le64_to_cpu(header.rgd_offset) << 9, SEEK_SET);
for (i = 0, tmp = header.rgd_offset + gd_size;
i < gt_count; i++, tmp += gt_size) {
ret = qemu_write_full(fd, &tmp, sizeof(tmp));
if (ret != sizeof(tmp)) {
ret = -errno;
goto exit;
}
}
/* write backup grain directory */
lseek(fd, le64_to_cpu(header.gd_offset) << 9, SEEK_SET);
for (i = 0, tmp = header.gd_offset + gd_size;
i < gt_count; i++, tmp += gt_size) {
ret = qemu_write_full(fd, &tmp, sizeof(tmp));
if (ret != sizeof(tmp)) {
ret = -errno;
goto exit;
}
}
/* compose the descriptor */
real_filename = filename;
if ((temp_str = strrchr(real_filename, '\\')) != NULL)
real_filename = temp_str + 1;
if ((temp_str = strrchr(real_filename, '/')) != NULL)
real_filename = temp_str + 1;
if ((temp_str = strrchr(real_filename, ':')) != NULL)
real_filename = temp_str + 1;
snprintf(desc, sizeof(desc), desc_template, (unsigned int)time(NULL),
total_size, real_filename,
(flags & BLOCK_FLAG_COMPAT6 ? 6 : 4),
total_size / (int64_t)(63 * 16));
/* write the descriptor */
lseek(fd, le64_to_cpu(header.desc_offset) << 9, SEEK_SET);
ret = qemu_write_full(fd, desc, strlen(desc));
if (ret != strlen(desc)) {
ret = -errno;
goto exit;
}
ret = 0;
exit:
close(fd);
return ret;
}
static void vmdk_close(BlockDriverState *bs)
{
BDRVVmdkState *s = bs->opaque;
qemu_free(s->l1_table);
qemu_free(s->l2_cache);
// try to close parent image, if exist
vmdk_parent_close(s->hd);
bdrv_delete(s->hd);
}
static void vmdk_flush(BlockDriverState *bs)
{
BDRVVmdkState *s = bs->opaque;
bdrv_flush(s->hd);
}
static QEMUOptionParameter vmdk_create_options[] = {
{
.name = BLOCK_OPT_SIZE,
.type = OPT_SIZE,
.help = "Virtual disk size"
},
{
.name = BLOCK_OPT_BACKING_FILE,
.type = OPT_STRING,
.help = "File name of a base image"
},
{
.name = BLOCK_OPT_COMPAT6,
.type = OPT_FLAG,
.help = "VMDK version 6 image"
},
{ NULL }
};
static BlockDriver bdrv_vmdk = {
.format_name = "vmdk",
.instance_size = sizeof(BDRVVmdkState),
.bdrv_probe = vmdk_probe,
.bdrv_file_open = vmdk_open,
.bdrv_read = vmdk_read,
.bdrv_write = vmdk_write,
.bdrv_close = vmdk_close,
.bdrv_create = vmdk_create,
.bdrv_flush = vmdk_flush,
.bdrv_is_allocated = vmdk_is_allocated,
.create_options = vmdk_create_options,
};
static void bdrv_vmdk_init(void)
{
bdrv_register(&bdrv_vmdk);
}
block_init(bdrv_vmdk_init);
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