diff options
| -rw-r--r-- | block-vmdk.c | 398 |
1 files changed, 353 insertions, 45 deletions
diff --git a/block-vmdk.c b/block-vmdk.c index 8279d66..28df8ae 100644 --- a/block-vmdk.c +++ b/block-vmdk.c @@ -22,6 +22,7 @@ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ + #include "vl.h" #include "block_int.h" @@ -59,7 +60,7 @@ typedef struct { #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; @@ -73,6 +74,7 @@ typedef struct BDRVVmdkState { 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) @@ -89,27 +91,278 @@ 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; @@ -120,8 +373,8 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) 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); @@ -133,17 +386,22 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) / 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]); @@ -153,9 +411,7 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) 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]); @@ -165,16 +421,43 @@ static int vmdk_open(BlockDriverState *bs, const char *filename, int flags) 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) { @@ -212,34 +495,41 @@ static uint64_t get_cluster_offset(BlockDriverState *bs, } } 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; @@ -265,9 +555,9 @@ static int vmdk_read(BlockDriverState *bs, int64_t sector_num, 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; @@ -275,11 +565,18 @@ static int vmdk_read(BlockDriverState *bs, int64_t sector_num, 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; @@ -293,8 +590,9 @@ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, 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); @@ -304,13 +602,17 @@ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, 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; } @@ -334,7 +636,7 @@ static int vmdk_create(const char *filename, int64_t total_size, "# 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" @@ -343,6 +645,9 @@ static int vmdk_create(const char *filename, int64_t total_size, 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); @@ -421,15 +726,18 @@ static int vmdk_create(const char *filename, int64_t total_size, 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 = { |