* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
+
#include "vl.h"
#include "block_int.h"
#define L2_CACHE_SIZE 16
typedef struct BDRVVmdkState {
- int fd;
+ BlockDriverState *hd;
int64_t l1_table_offset;
int64_t l1_backup_table_offset;
uint32_t *l1_table;
uint32_t l2_cache_counts[L2_CACHE_SIZE];
unsigned int cluster_sectors;
+ uint32_t parent_cid;
} BDRVVmdkState;
static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename)
return 0;
}
-static int vmdk_open(BlockDriverState *bs, const char *filename, int flags)
+#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;
- int fd, i;
- uint32_t magic;
- int l1_size;
+ char desc[DESC_SIZE];
+ uint32_t cid;
+ 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)) != 0) {
+ 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");
+ strcpy(tmp_desc, tmp_str);
+ if ((p_name = strstr(desc,"CID")) != 0) {
+ p_name += sizeof("CID");
+ sprintf(p_name,"%x\n",cid);
+ strcat(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 = s->hd->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;
+ 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];
+ 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 %lu 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 -1;
+ p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE);
+ if (p_fd < 0) {
+ close(snp_fd);
+ return -1;
+ }
+
+ /* read the header */
+ if (lseek(p_fd, 0x0, SEEK_SET) == -1)
+ goto fail;
+ if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE)
+ goto fail;
+
+ /* write the header */
+ if (lseek(snp_fd, 0x0, SEEK_SET) == -1)
+ goto fail;
+ if (write(snp_fd, hdr, HEADER_SIZE) == -1)
+ goto fail;
+
+ memset(&header, 0, sizeof(header));
+ memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC
+
+ ftruncate(snp_fd, header.grain_offset << 9);
+ /* the descriptor offset = 0x200 */
+ if (lseek(p_fd, 0x200, SEEK_SET) == -1)
+ goto fail;
+ if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE)
+ goto fail;
+
+ if ((p_name = strstr(p_desc,"CID")) != 0) {
+ 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;
+
+ sprintf(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)
+ goto fail;
+ if (write(snp_fd, s_desc, strlen(s_desc)) == -1)
+ goto fail;
- fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE);
- if (fd < 0) {
- fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
- if (fd < 0)
+ 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)
+ 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 (!rgd_buf)
+ goto fail;
+ if (lseek(p_fd, rgd_offset, SEEK_SET) == -1)
+ goto fail_rgd;
+ if (read(p_fd, rgd_buf, gd_size) != gd_size)
+ goto fail_rgd;
+ if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1)
+ goto fail_rgd;
+ if (write(snp_fd, rgd_buf, gd_size) == -1)
+ goto fail_rgd;
+ qemu_free(rgd_buf);
+
+ /* write GD */
+ gd_buf = qemu_malloc(gd_size);
+ if (!gd_buf)
+ goto fail_rgd;
+ if (lseek(p_fd, gd_offset, SEEK_SET) == -1)
+ goto fail_gd;
+ if (read(p_fd, gd_buf, gd_size) != gd_size)
+ goto fail_gd;
+ if (lseek(snp_fd, gd_offset, SEEK_SET) == -1)
+ goto fail_gd;
+ if (write(snp_fd, gd_buf, gd_size) == -1)
+ goto fail_gd;
+ qemu_free(gd_buf);
+
+ close(p_fd);
+ close(snp_fd);
+ return 0;
+
+ fail_gd:
+ qemu_free(gd_buf);
+ fail_rgd:
+ qemu_free(rgd_buf);
+ fail:
+ close(p_fd);
+ close(snp_fd);
+ return -1;
+}
+
+static void vmdk_parent_close(BlockDriverState *bs)
+{
+ if (bs->backing_hd)
+ bdrv_close(bs->backing_hd);
+}
+
+
+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")) != 0) {
+ char *end_name;
+ struct stat file_buf;
+
+ p_name += sizeof("parentFileNameHint") + 1;
+ if ((end_name = strchr(p_name,'\"')) == 0)
+ return -1;
+
+ strncpy(s->hd->backing_file, p_name, end_name - p_name);
+ if (stat(s->hd->backing_file, &file_buf) != 0) {
+ path_combine(parent_img_name, sizeof(parent_img_name),
+ filename, s->hd->backing_file);
+ } else {
+ strcpy(parent_img_name, s->hd->backing_file);
+ }
+
+ s->hd->backing_hd = bdrv_new("");
+ if (!s->hd->backing_hd) {
+ failure:
+ bdrv_close(s->hd);
return -1;
- bs->read_only = 1;
+ }
+ if (bdrv_open(s->hd->backing_hd, parent_img_name, 0) < 0)
+ goto failure;
}
- if (read(fd, &magic, sizeof(magic)) != sizeof(magic))
+
+ 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;
+
+ 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 (read(fd, &header, sizeof(header)) !=
- sizeof(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_entry_sectors = s->l2_size * s->cluster_sectors;
} else if (magic == VMDK4_MAGIC) {
VMDK4Header header;
-
- if (read(fd, &header, sizeof(header)) != sizeof(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->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;
+
+ // 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 (!s->l1_table)
goto fail;
- if (lseek(fd, s->l1_table_offset, SEEK_SET) == -1)
- goto fail;
- if (read(fd, s->l1_table, l1_size) != 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]);
s->l1_backup_table = qemu_malloc(l1_size);
if (!s->l1_backup_table)
goto fail;
- if (lseek(fd, s->l1_backup_table_offset, SEEK_SET) == -1)
- goto fail;
- if (read(fd, s->l1_backup_table, l1_size) != 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));
if (!s->l2_cache)
goto fail;
- s->fd = fd;
return 0;
fail:
qemu_free(s->l1_backup_table);
qemu_free(s->l1_table);
qemu_free(s->l2_cache);
- close(fd);
+ bdrv_delete(s->hd);
return -1;
}
+static uint64_t get_cluster_offset(BlockDriverState *bs, 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 (s->hd->backing_hd) {
+ BDRVVmdkState *ps = s->hd->backing_hd->opaque;
+
+ if (!vmdk_is_cid_valid(bs))
+ return -1;
+ parent_cluster_offset = get_cluster_offset(s->hd->backing_hd, offset, allocate);
+ if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) !=
+ ps->cluster_sectors*512)
+ return -1;
+
+ if (bdrv_pwrite(s->hd, cluster_offset << 9, whole_grain, sizeof(whole_grain)) !=
+ sizeof(whole_grain))
+ return -1;
+ }
+ return 0;
+}
+
static uint64_t get_cluster_offset(BlockDriverState *bs,
uint64_t offset, int allocate)
{
}
}
l2_table = s->l2_cache + (min_index * s->l2_size);
- lseek(s->fd, (int64_t)l2_offset * 512, SEEK_SET);
- if (read(s->fd, l2_table, s->l2_size * sizeof(uint32_t)) !=
- s->l2_size * sizeof(uint32_t))
+ 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) {
+ struct stat file_buf;
+
if (!allocate)
return 0;
- cluster_offset = lseek(s->fd, 0, SEEK_END);
- ftruncate(s->fd, cluster_offset + (s->cluster_sectors << 9));
+ stat(s->hd->filename, &file_buf);
+ cluster_offset = file_buf.st_size;
+ bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9));
+
cluster_offset >>= 9;
/* update L2 table */
tmp = cpu_to_le32(cluster_offset);
l2_table[l2_index] = tmp;
- lseek(s->fd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), SEEK_SET);
- if (write(s->fd, &tmp, sizeof(tmp)) != sizeof(tmp))
+ if (bdrv_pwrite(s->hd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)),
+ &tmp, sizeof(tmp)) != sizeof(tmp))
return 0;
/* update backup L2 table */
if (s->l1_backup_table_offset != 0) {
l2_offset = s->l1_backup_table[l1_index];
- lseek(s->fd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), SEEK_SET);
- if (write(s->fd, &tmp, sizeof(tmp)) != sizeof(tmp))
+ if (bdrv_pwrite(s->hd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)),
+ &tmp, sizeof(tmp)) != sizeof(tmp))
return 0;
}
+
+ if (get_whole_cluster(bs, cluster_offset, offset, allocate) == -1)
+ return 0;
}
cluster_offset <<= 9;
return cluster_offset;
uint8_t *buf, int nb_sectors)
{
BDRVVmdkState *s = bs->opaque;
- int ret, index_in_cluster, n;
+ int index_in_cluster, n, ret;
uint64_t cluster_offset;
-
+
while (nb_sectors > 0) {
cluster_offset = get_cluster_offset(bs, sector_num << 9, 0);
index_in_cluster = sector_num % s->cluster_sectors;
if (n > nb_sectors)
n = nb_sectors;
if (!cluster_offset) {
- memset(buf, 0, 512 * n);
+ // try to read from parent image, if exist
+ if (s->hd->backing_hd) {
+ if (!vmdk_is_cid_valid(bs))
+ return -1;
+ ret = bdrv_read(s->hd->backing_hd, sector_num, buf, n);
+ if (ret < 0)
+ return -1;
+ } else {
+ memset(buf, 0, 512 * n);
+ }
} else {
- lseek(s->fd, cluster_offset + index_in_cluster * 512, SEEK_SET);
- ret = read(s->fd, buf, n * 512);
- if (ret != n * 512)
+ if(bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
return -1;
}
nb_sectors -= n;
const uint8_t *buf, int nb_sectors)
{
BDRVVmdkState *s = bs->opaque;
- int ret, index_in_cluster, n;
+ int index_in_cluster, n;
uint64_t cluster_offset;
+ static int cid_update = 0;
while (nb_sectors > 0) {
index_in_cluster = sector_num & (s->cluster_sectors - 1);
cluster_offset = get_cluster_offset(bs, sector_num << 9, 1);
if (!cluster_offset)
return -1;
- lseek(s->fd, cluster_offset + index_in_cluster * 512, SEEK_SET);
- ret = write(s->fd, buf, n * 512);
- if (ret != n * 512)
+ if (bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
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;
}
"# The Disk Data Base \n"
"#DDB\n"
"\n"
- "ddb.virtualHWVersion = \"3\"\n"
+ "ddb.virtualHWVersion = \"4\"\n"
"ddb.geometry.cylinders = \"%lu\"\n"
"ddb.geometry.heads = \"16\"\n"
"ddb.geometry.sectors = \"63\"\n"
const char *real_filename, *temp_str;
/* 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);
static void vmdk_close(BlockDriverState *bs)
{
BDRVVmdkState *s = bs->opaque;
+
qemu_free(s->l1_table);
qemu_free(s->l2_cache);
- close(s->fd);
+ bdrv_delete(s->hd);
+ // try to close parent image, if exist
+ vmdk_parent_close(s->hd);
}
static void vmdk_flush(BlockDriverState *bs)
{
BDRVVmdkState *s = bs->opaque;
- fsync(s->fd);
+ bdrv_flush(s->hd);
}
BlockDriver bdrv_vmdk = {
projects / qemu / commitdiff