Annotation of qemu/block-vmdk.c, revision 1.1.1.5

1.1       root        1: /*
                      2:  * Block driver for the VMDK format
1.1.1.5 ! root        3:  *
1.1       root        4:  * Copyright (c) 2004 Fabrice Bellard
                      5:  * Copyright (c) 2005 Filip Navara
1.1.1.5 ! root        6:  *
1.1       root        7:  * Permission is hereby granted, free of charge, to any person obtaining a copy
                      8:  * of this software and associated documentation files (the "Software"), to deal
                      9:  * in the Software without restriction, including without limitation the rights
                     10:  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
                     11:  * copies of the Software, and to permit persons to whom the Software is
                     12:  * furnished to do so, subject to the following conditions:
                     13:  *
                     14:  * The above copyright notice and this permission notice shall be included in
                     15:  * all copies or substantial portions of the Software.
                     16:  *
                     17:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
                     18:  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
                     19:  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
                     20:  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
                     21:  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
                     22:  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
                     23:  * THE SOFTWARE.
                     24:  */
1.1.1.4   root       25: 
1.1.1.5 ! root       26: #include "qemu-common.h"
1.1       root       27: #include "block_int.h"
                     28: 
                     29: #define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D')
                     30: #define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V')
                     31: 
                     32: typedef struct {
                     33:     uint32_t version;
                     34:     uint32_t flags;
                     35:     uint32_t disk_sectors;
                     36:     uint32_t granularity;
                     37:     uint32_t l1dir_offset;
                     38:     uint32_t l1dir_size;
                     39:     uint32_t file_sectors;
                     40:     uint32_t cylinders;
                     41:     uint32_t heads;
                     42:     uint32_t sectors_per_track;
                     43: } VMDK3Header;
                     44: 
                     45: typedef struct {
                     46:     uint32_t version;
                     47:     uint32_t flags;
                     48:     int64_t capacity;
                     49:     int64_t granularity;
                     50:     int64_t desc_offset;
                     51:     int64_t desc_size;
                     52:     int32_t num_gtes_per_gte;
                     53:     int64_t rgd_offset;
                     54:     int64_t gd_offset;
                     55:     int64_t grain_offset;
                     56:     char filler[1];
                     57:     char check_bytes[4];
                     58: } __attribute__((packed)) VMDK4Header;
                     59: 
                     60: #define L2_CACHE_SIZE 16
                     61: 
                     62: typedef struct BDRVVmdkState {
1.1.1.4   root       63:     BlockDriverState *hd;
1.1       root       64:     int64_t l1_table_offset;
                     65:     int64_t l1_backup_table_offset;
                     66:     uint32_t *l1_table;
                     67:     uint32_t *l1_backup_table;
                     68:     unsigned int l1_size;
                     69:     uint32_t l1_entry_sectors;
                     70: 
                     71:     unsigned int l2_size;
                     72:     uint32_t *l2_cache;
                     73:     uint32_t l2_cache_offsets[L2_CACHE_SIZE];
                     74:     uint32_t l2_cache_counts[L2_CACHE_SIZE];
                     75: 
                     76:     unsigned int cluster_sectors;
1.1.1.4   root       77:     uint32_t parent_cid;
1.1.1.5 ! root       78:     int is_parent;
1.1       root       79: } BDRVVmdkState;
                     80: 
1.1.1.5 ! root       81: typedef struct VmdkMetaData {
        !            82:     uint32_t offset;
        !            83:     unsigned int l1_index;
        !            84:     unsigned int l2_index;
        !            85:     unsigned int l2_offset;
        !            86:     int valid;
        !            87: } VmdkMetaData;
        !            88: 
        !            89: typedef struct ActiveBDRVState{
        !            90:     BlockDriverState *hd;            // active image handler
        !            91:     uint64_t cluster_offset;         // current write offset
        !            92: }ActiveBDRVState;
        !            93: 
        !            94: static ActiveBDRVState activeBDRV;
        !            95: 
        !            96: 
1.1       root       97: static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename)
                     98: {
                     99:     uint32_t magic;
                    100: 
                    101:     if (buf_size < 4)
                    102:         return 0;
                    103:     magic = be32_to_cpu(*(uint32_t *)buf);
                    104:     if (magic == VMDK3_MAGIC ||
                    105:         magic == VMDK4_MAGIC)
                    106:         return 100;
                    107:     else
                    108:         return 0;
                    109: }
                    110: 
1.1.1.4   root      111: #define CHECK_CID 1
                    112: 
1.1.1.5 ! root      113: #define SECTOR_SIZE 512
1.1.1.4   root      114: #define DESC_SIZE 20*SECTOR_SIZE       // 20 sectors of 512 bytes each
1.1.1.5 ! root      115: #define HEADER_SIZE 512                        // first sector of 512 bytes
1.1.1.4   root      116: 
                    117: static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent)
1.1       root      118: {
                    119:     BDRVVmdkState *s = bs->opaque;
1.1.1.4   root      120:     char desc[DESC_SIZE];
                    121:     uint32_t cid;
1.1.1.5 ! root      122:     char *p_name, *cid_str;
1.1.1.4   root      123:     size_t cid_str_size;
                    124: 
                    125:     /* the descriptor offset = 0x200 */
                    126:     if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
                    127:         return 0;
                    128: 
                    129:     if (parent) {
                    130:         cid_str = "parentCID";
                    131:         cid_str_size = sizeof("parentCID");
                    132:     } else {
                    133:         cid_str = "CID";
                    134:         cid_str_size = sizeof("CID");
                    135:     }
                    136: 
                    137:     if ((p_name = strstr(desc,cid_str)) != 0) {
                    138:         p_name += cid_str_size;
                    139:         sscanf(p_name,"%x",&cid);
                    140:     }
                    141: 
                    142:     return cid;
                    143: }
                    144: 
                    145: static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
                    146: {
                    147:     BDRVVmdkState *s = bs->opaque;
                    148:     char desc[DESC_SIZE], tmp_desc[DESC_SIZE];
                    149:     char *p_name, *tmp_str;
                    150: 
                    151:     /* the descriptor offset = 0x200 */
                    152:     if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
                    153:         return -1;
                    154: 
                    155:     tmp_str = strstr(desc,"parentCID");
                    156:     strcpy(tmp_desc, tmp_str);
                    157:     if ((p_name = strstr(desc,"CID")) != 0) {
                    158:         p_name += sizeof("CID");
                    159:         sprintf(p_name,"%x\n",cid);
                    160:         strcat(desc,tmp_desc);
                    161:     }
                    162: 
                    163:     if (bdrv_pwrite(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
                    164:         return -1;
                    165:     return 0;
                    166: }
                    167: 
                    168: static int vmdk_is_cid_valid(BlockDriverState *bs)
                    169: {
                    170: #ifdef CHECK_CID
                    171:     BDRVVmdkState *s = bs->opaque;
                    172:     BlockDriverState *p_bs = s->hd->backing_hd;
                    173:     uint32_t cur_pcid;
                    174: 
                    175:     if (p_bs) {
                    176:         cur_pcid = vmdk_read_cid(p_bs,0);
                    177:         if (s->parent_cid != cur_pcid)
                    178:             // CID not valid
                    179:             return 0;
                    180:     }
                    181: #endif
                    182:     // CID valid
                    183:     return 1;
                    184: }
                    185: 
                    186: static int vmdk_snapshot_create(const char *filename, const char *backing_file)
                    187: {
                    188:     int snp_fd, p_fd;
                    189:     uint32_t p_cid;
1.1.1.5 ! root      190:     char *p_name, *gd_buf, *rgd_buf;
1.1.1.4   root      191:     const char *real_filename, *temp_str;
                    192:     VMDK4Header header;
                    193:     uint32_t gde_entries, gd_size;
                    194:     int64_t gd_offset, rgd_offset, capacity, gt_size;
                    195:     char p_desc[DESC_SIZE], s_desc[DESC_SIZE], hdr[HEADER_SIZE];
                    196:     char *desc_template =
                    197:     "# Disk DescriptorFile\n"
                    198:     "version=1\n"
                    199:     "CID=%x\n"
                    200:     "parentCID=%x\n"
                    201:     "createType=\"monolithicSparse\"\n"
                    202:     "parentFileNameHint=\"%s\"\n"
                    203:     "\n"
                    204:     "# Extent description\n"
                    205:     "RW %lu SPARSE \"%s\"\n"
                    206:     "\n"
                    207:     "# The Disk Data Base \n"
                    208:     "#DDB\n"
                    209:     "\n";
                    210: 
                    211:     snp_fd = open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, 0644);
                    212:     if (snp_fd < 0)
                    213:         return -1;
                    214:     p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE);
                    215:     if (p_fd < 0) {
                    216:         close(snp_fd);
                    217:         return -1;
                    218:     }
                    219: 
                    220:     /* read the header */
                    221:     if (lseek(p_fd, 0x0, SEEK_SET) == -1)
                    222:         goto fail;
                    223:     if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE)
                    224:         goto fail;
                    225: 
                    226:     /* write the header */
                    227:     if (lseek(snp_fd, 0x0, SEEK_SET) == -1)
                    228:         goto fail;
                    229:     if (write(snp_fd, hdr, HEADER_SIZE) == -1)
                    230:         goto fail;
                    231: 
                    232:     memset(&header, 0, sizeof(header));
                    233:     memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC
                    234: 
                    235:     ftruncate(snp_fd, header.grain_offset << 9);
                    236:     /* the descriptor offset = 0x200 */
                    237:     if (lseek(p_fd, 0x200, SEEK_SET) == -1)
                    238:         goto fail;
                    239:     if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE)
                    240:         goto fail;
                    241: 
                    242:     if ((p_name = strstr(p_desc,"CID")) != 0) {
                    243:         p_name += sizeof("CID");
                    244:         sscanf(p_name,"%x",&p_cid);
                    245:     }
                    246: 
                    247:     real_filename = filename;
                    248:     if ((temp_str = strrchr(real_filename, '\\')) != NULL)
                    249:         real_filename = temp_str + 1;
                    250:     if ((temp_str = strrchr(real_filename, '/')) != NULL)
                    251:         real_filename = temp_str + 1;
                    252:     if ((temp_str = strrchr(real_filename, ':')) != NULL)
                    253:         real_filename = temp_str + 1;
                    254: 
                    255:     sprintf(s_desc, desc_template, p_cid, p_cid, backing_file
                    256:             , (uint32_t)header.capacity, real_filename);
                    257: 
                    258:     /* write the descriptor */
                    259:     if (lseek(snp_fd, 0x200, SEEK_SET) == -1)
                    260:         goto fail;
                    261:     if (write(snp_fd, s_desc, strlen(s_desc)) == -1)
                    262:         goto fail;
1.1       root      263: 
1.1.1.4   root      264:     gd_offset = header.gd_offset * SECTOR_SIZE;     // offset of GD table
                    265:     rgd_offset = header.rgd_offset * SECTOR_SIZE;   // offset of RGD table
                    266:     capacity = header.capacity * SECTOR_SIZE;       // Extent size
                    267:     /*
                    268:      * Each GDE span 32M disk, means:
                    269:      * 512 GTE per GT, each GTE points to grain
                    270:      */
                    271:     gt_size = (int64_t)header.num_gtes_per_gte * header.granularity * SECTOR_SIZE;
                    272:     if (!gt_size)
                    273:         goto fail;
1.1.1.5 ! root      274:     gde_entries = (uint32_t)(capacity / gt_size);  // number of gde/rgde
1.1.1.4   root      275:     gd_size = gde_entries * sizeof(uint32_t);
                    276: 
                    277:     /* write RGD */
                    278:     rgd_buf = qemu_malloc(gd_size);
                    279:     if (!rgd_buf)
                    280:         goto fail;
                    281:     if (lseek(p_fd, rgd_offset, SEEK_SET) == -1)
                    282:         goto fail_rgd;
                    283:     if (read(p_fd, rgd_buf, gd_size) != gd_size)
                    284:         goto fail_rgd;
                    285:     if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1)
                    286:         goto fail_rgd;
                    287:     if (write(snp_fd, rgd_buf, gd_size) == -1)
                    288:         goto fail_rgd;
                    289:     qemu_free(rgd_buf);
                    290: 
                    291:     /* write GD */
                    292:     gd_buf = qemu_malloc(gd_size);
                    293:     if (!gd_buf)
                    294:         goto fail_rgd;
                    295:     if (lseek(p_fd, gd_offset, SEEK_SET) == -1)
                    296:         goto fail_gd;
                    297:     if (read(p_fd, gd_buf, gd_size) != gd_size)
                    298:         goto fail_gd;
                    299:     if (lseek(snp_fd, gd_offset, SEEK_SET) == -1)
                    300:         goto fail_gd;
                    301:     if (write(snp_fd, gd_buf, gd_size) == -1)
                    302:         goto fail_gd;
                    303:     qemu_free(gd_buf);
                    304: 
                    305:     close(p_fd);
                    306:     close(snp_fd);
                    307:     return 0;
                    308: 
                    309:     fail_gd:
                    310:     qemu_free(gd_buf);
1.1.1.5 ! root      311:     fail_rgd:
1.1.1.4   root      312:     qemu_free(rgd_buf);
                    313:     fail:
                    314:     close(p_fd);
                    315:     close(snp_fd);
                    316:     return -1;
                    317: }
                    318: 
                    319: static void vmdk_parent_close(BlockDriverState *bs)
                    320: {
                    321:     if (bs->backing_hd)
                    322:         bdrv_close(bs->backing_hd);
                    323: }
                    324: 
1.1.1.5 ! root      325: int parent_open = 0;
1.1.1.4   root      326: static int vmdk_parent_open(BlockDriverState *bs, const char * filename)
                    327: {
                    328:     BDRVVmdkState *s = bs->opaque;
1.1.1.5 ! root      329:     char *p_name;
1.1.1.4   root      330:     char desc[DESC_SIZE];
                    331:     char parent_img_name[1024];
                    332: 
                    333:     /* the descriptor offset = 0x200 */
                    334:     if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
                    335:         return -1;
                    336: 
                    337:     if ((p_name = strstr(desc,"parentFileNameHint")) != 0) {
                    338:         char *end_name;
                    339:         struct stat file_buf;
                    340: 
                    341:         p_name += sizeof("parentFileNameHint") + 1;
                    342:         if ((end_name = strchr(p_name,'\"')) == 0)
1.1       root      343:             return -1;
1.1.1.5 ! root      344: 
1.1.1.4   root      345:         strncpy(s->hd->backing_file, p_name, end_name - p_name);
                    346:         if (stat(s->hd->backing_file, &file_buf) != 0) {
                    347:             path_combine(parent_img_name, sizeof(parent_img_name),
                    348:                          filename, s->hd->backing_file);
                    349:         } else {
                    350:             strcpy(parent_img_name, s->hd->backing_file);
                    351:         }
                    352: 
                    353:         s->hd->backing_hd = bdrv_new("");
                    354:         if (!s->hd->backing_hd) {
                    355:             failure:
                    356:             bdrv_close(s->hd);
                    357:             return -1;
                    358:         }
1.1.1.5 ! root      359:         parent_open = 1;
        !           360:         if (bdrv_open(s->hd->backing_hd, parent_img_name, BDRV_O_RDONLY) < 0)
1.1.1.4   root      361:             goto failure;
1.1.1.5 ! root      362:         parent_open = 0;
1.1       root      363:     }
1.1.1.4   root      364: 
                    365:     return 0;
                    366: }
                    367: 
                    368: static int vmdk_open(BlockDriverState *bs, const char *filename, int flags)
                    369: {
                    370:     BDRVVmdkState *s = bs->opaque;
                    371:     uint32_t magic;
                    372:     int l1_size, i, ret;
                    373: 
1.1.1.5 ! root      374:     if (parent_open)
        !           375:         // Parent must be opened as RO.
        !           376:         flags = BDRV_O_RDONLY;
        !           377:     fprintf(stderr, "(VMDK) image open: flags=0x%x filename=%s\n", flags, bs->filename);
        !           378: 
1.1.1.4   root      379:     ret = bdrv_file_open(&s->hd, filename, flags);
                    380:     if (ret < 0)
                    381:         return ret;
                    382:     if (bdrv_pread(s->hd, 0, &magic, sizeof(magic)) != sizeof(magic))
1.1       root      383:         goto fail;
1.1.1.4   root      384: 
1.1       root      385:     magic = be32_to_cpu(magic);
                    386:     if (magic == VMDK3_MAGIC) {
                    387:         VMDK3Header header;
1.1.1.4   root      388: 
                    389:         if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
1.1       root      390:             goto fail;
                    391:         s->cluster_sectors = le32_to_cpu(header.granularity);
                    392:         s->l2_size = 1 << 9;
                    393:         s->l1_size = 1 << 6;
                    394:         bs->total_sectors = le32_to_cpu(header.disk_sectors);
                    395:         s->l1_table_offset = le32_to_cpu(header.l1dir_offset) << 9;
                    396:         s->l1_backup_table_offset = 0;
                    397:         s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
                    398:     } else if (magic == VMDK4_MAGIC) {
                    399:         VMDK4Header header;
1.1.1.4   root      400: 
                    401:         if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
1.1       root      402:             goto fail;
1.1.1.2   root      403:         bs->total_sectors = le64_to_cpu(header.capacity);
                    404:         s->cluster_sectors = le64_to_cpu(header.granularity);
1.1       root      405:         s->l2_size = le32_to_cpu(header.num_gtes_per_gte);
                    406:         s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
                    407:         if (s->l1_entry_sectors <= 0)
                    408:             goto fail;
1.1.1.5 ! root      409:         s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1)
1.1       root      410:             / s->l1_entry_sectors;
                    411:         s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9;
                    412:         s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
1.1.1.4   root      413: 
1.1.1.5 ! root      414:         if (parent_open)
        !           415:             s->is_parent = 1;
        !           416:         else
        !           417:             s->is_parent = 0;
        !           418: 
1.1.1.4   root      419:         // try to open parent images, if exist
                    420:         if (vmdk_parent_open(bs, filename) != 0)
                    421:             goto fail;
                    422:         // write the CID once after the image creation
                    423:         s->parent_cid = vmdk_read_cid(bs,1);
1.1       root      424:     } else {
                    425:         goto fail;
                    426:     }
1.1.1.4   root      427: 
1.1       root      428:     /* read the L1 table */
                    429:     l1_size = s->l1_size * sizeof(uint32_t);
                    430:     s->l1_table = qemu_malloc(l1_size);
                    431:     if (!s->l1_table)
                    432:         goto fail;
1.1.1.4   root      433:     if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, l1_size) != l1_size)
1.1       root      434:         goto fail;
                    435:     for(i = 0; i < s->l1_size; i++) {
                    436:         le32_to_cpus(&s->l1_table[i]);
                    437:     }
                    438: 
                    439:     if (s->l1_backup_table_offset) {
                    440:         s->l1_backup_table = qemu_malloc(l1_size);
                    441:         if (!s->l1_backup_table)
                    442:             goto fail;
1.1.1.4   root      443:         if (bdrv_pread(s->hd, s->l1_backup_table_offset, s->l1_backup_table, l1_size) != l1_size)
1.1       root      444:             goto fail;
                    445:         for(i = 0; i < s->l1_size; i++) {
                    446:             le32_to_cpus(&s->l1_backup_table[i]);
                    447:         }
                    448:     }
                    449: 
                    450:     s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t));
                    451:     if (!s->l2_cache)
                    452:         goto fail;
                    453:     return 0;
                    454:  fail:
                    455:     qemu_free(s->l1_backup_table);
                    456:     qemu_free(s->l1_table);
                    457:     qemu_free(s->l2_cache);
1.1.1.4   root      458:     bdrv_delete(s->hd);
1.1       root      459:     return -1;
                    460: }
                    461: 
1.1.1.5 ! root      462: static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
        !           463:                                    uint64_t offset, int allocate);
1.1.1.4   root      464: 
                    465: static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset,
                    466:                              uint64_t offset, int allocate)
                    467: {
                    468:     uint64_t parent_cluster_offset;
                    469:     BDRVVmdkState *s = bs->opaque;
                    470:     uint8_t  whole_grain[s->cluster_sectors*512];        // 128 sectors * 512 bytes each = grain size 64KB
                    471: 
                    472:     // we will be here if it's first write on non-exist grain(cluster).
                    473:     // try to read from parent image, if exist
                    474:     if (s->hd->backing_hd) {
                    475:         BDRVVmdkState *ps = s->hd->backing_hd->opaque;
                    476: 
                    477:         if (!vmdk_is_cid_valid(bs))
                    478:             return -1;
                    479: 
1.1.1.5 ! root      480:         parent_cluster_offset = get_cluster_offset(s->hd->backing_hd, NULL, offset, allocate);
        !           481: 
        !           482:         if (parent_cluster_offset) {
        !           483:             BDRVVmdkState *act_s = activeBDRV.hd->opaque;
        !           484: 
        !           485:             if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) != ps->cluster_sectors*512)
        !           486:                 return -1;
        !           487: 
        !           488:             //Write grain only into the active image
        !           489:             if (bdrv_pwrite(act_s->hd, activeBDRV.cluster_offset << 9, whole_grain, sizeof(whole_grain)) != sizeof(whole_grain))
        !           490:                 return -1;
        !           491:         }
        !           492:     }
        !           493:     return 0;
        !           494: }
        !           495: 
        !           496: static int vmdk_L2update(BlockDriverState *bs, VmdkMetaData *m_data)
        !           497: {
        !           498:     BDRVVmdkState *s = bs->opaque;
        !           499: 
        !           500:     /* update L2 table */
        !           501:     if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)),
        !           502:                     &(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset))
        !           503:         return -1;
        !           504:     /* update backup L2 table */
        !           505:     if (s->l1_backup_table_offset != 0) {
        !           506:         m_data->l2_offset = s->l1_backup_table[m_data->l1_index];
        !           507:         if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)),
        !           508:                         &(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset))
1.1.1.4   root      509:             return -1;
                    510:     }
1.1.1.5 ! root      511: 
1.1.1.4   root      512:     return 0;
                    513: }
                    514: 
1.1.1.5 ! root      515: static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
1.1       root      516:                                    uint64_t offset, int allocate)
                    517: {
                    518:     BDRVVmdkState *s = bs->opaque;
                    519:     unsigned int l1_index, l2_offset, l2_index;
                    520:     int min_index, i, j;
1.1.1.5 ! root      521:     uint32_t min_count, *l2_table, tmp = 0;
1.1       root      522:     uint64_t cluster_offset;
1.1.1.5 ! root      523: 
        !           524:     if (m_data)
        !           525:         m_data->valid = 0;
        !           526: 
1.1       root      527:     l1_index = (offset >> 9) / s->l1_entry_sectors;
                    528:     if (l1_index >= s->l1_size)
                    529:         return 0;
                    530:     l2_offset = s->l1_table[l1_index];
                    531:     if (!l2_offset)
                    532:         return 0;
                    533:     for(i = 0; i < L2_CACHE_SIZE; i++) {
                    534:         if (l2_offset == s->l2_cache_offsets[i]) {
                    535:             /* increment the hit count */
                    536:             if (++s->l2_cache_counts[i] == 0xffffffff) {
                    537:                 for(j = 0; j < L2_CACHE_SIZE; j++) {
                    538:                     s->l2_cache_counts[j] >>= 1;
                    539:                 }
                    540:             }
                    541:             l2_table = s->l2_cache + (i * s->l2_size);
                    542:             goto found;
                    543:         }
                    544:     }
                    545:     /* not found: load a new entry in the least used one */
                    546:     min_index = 0;
                    547:     min_count = 0xffffffff;
                    548:     for(i = 0; i < L2_CACHE_SIZE; i++) {
                    549:         if (s->l2_cache_counts[i] < min_count) {
                    550:             min_count = s->l2_cache_counts[i];
                    551:             min_index = i;
                    552:         }
                    553:     }
                    554:     l2_table = s->l2_cache + (min_index * s->l2_size);
1.1.1.5 ! root      555:     if (bdrv_pread(s->hd, (int64_t)l2_offset * 512, l2_table, s->l2_size * sizeof(uint32_t)) !=
1.1.1.4   root      556:                                                                         s->l2_size * sizeof(uint32_t))
1.1       root      557:         return 0;
1.1.1.4   root      558: 
1.1       root      559:     s->l2_cache_offsets[min_index] = l2_offset;
                    560:     s->l2_cache_counts[min_index] = 1;
                    561:  found:
                    562:     l2_index = ((offset >> 9) / s->cluster_sectors) % s->l2_size;
                    563:     cluster_offset = le32_to_cpu(l2_table[l2_index]);
1.1.1.4   root      564: 
1.1.1.5 ! root      565:     if (!cluster_offset) {
1.1       root      566:         if (!allocate)
                    567:             return 0;
1.1.1.5 ! root      568:         // Avoid the L2 tables update for the images that have snapshots.
        !           569:         if (!s->is_parent) {
        !           570:             cluster_offset = bdrv_getlength(s->hd);
        !           571:             bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9));
        !           572: 
        !           573:             cluster_offset >>= 9;
        !           574:             tmp = cpu_to_le32(cluster_offset);
        !           575:             l2_table[l2_index] = tmp;
        !           576:             // Save the active image state
        !           577:             activeBDRV.cluster_offset = cluster_offset;
        !           578:             activeBDRV.hd = bs;
1.1       root      579:         }
1.1.1.5 ! root      580:         /* First of all we write grain itself, to avoid race condition
        !           581:          * that may to corrupt the image.
        !           582:          * This problem may occur because of insufficient space on host disk
        !           583:          * or inappropriate VM shutdown.
        !           584:          */
1.1.1.4   root      585:         if (get_whole_cluster(bs, cluster_offset, offset, allocate) == -1)
                    586:             return 0;
1.1.1.5 ! root      587: 
        !           588:         if (m_data) {
        !           589:             m_data->offset = tmp;
        !           590:             m_data->l1_index = l1_index;
        !           591:             m_data->l2_index = l2_index;
        !           592:             m_data->l2_offset = l2_offset;
        !           593:             m_data->valid = 1;
        !           594:         }
1.1       root      595:     }
                    596:     cluster_offset <<= 9;
                    597:     return cluster_offset;
                    598: }
                    599: 
1.1.1.5 ! root      600: static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num,
1.1       root      601:                              int nb_sectors, int *pnum)
                    602: {
                    603:     BDRVVmdkState *s = bs->opaque;
                    604:     int index_in_cluster, n;
                    605:     uint64_t cluster_offset;
                    606: 
1.1.1.5 ! root      607:     cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0);
1.1       root      608:     index_in_cluster = sector_num % s->cluster_sectors;
                    609:     n = s->cluster_sectors - index_in_cluster;
                    610:     if (n > nb_sectors)
                    611:         n = nb_sectors;
                    612:     *pnum = n;
                    613:     return (cluster_offset != 0);
                    614: }
                    615: 
1.1.1.5 ! root      616: static int vmdk_read(BlockDriverState *bs, int64_t sector_num,
1.1       root      617:                     uint8_t *buf, int nb_sectors)
                    618: {
                    619:     BDRVVmdkState *s = bs->opaque;
1.1.1.4   root      620:     int index_in_cluster, n, ret;
1.1       root      621:     uint64_t cluster_offset;
1.1.1.4   root      622: 
1.1       root      623:     while (nb_sectors > 0) {
1.1.1.5 ! root      624:         cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0);
1.1       root      625:         index_in_cluster = sector_num % s->cluster_sectors;
                    626:         n = s->cluster_sectors - index_in_cluster;
                    627:         if (n > nb_sectors)
                    628:             n = nb_sectors;
                    629:         if (!cluster_offset) {
1.1.1.4   root      630:             // try to read from parent image, if exist
                    631:             if (s->hd->backing_hd) {
                    632:                 if (!vmdk_is_cid_valid(bs))
                    633:                     return -1;
                    634:                 ret = bdrv_read(s->hd->backing_hd, sector_num, buf, n);
                    635:                 if (ret < 0)
                    636:                     return -1;
                    637:             } else {
                    638:                 memset(buf, 0, 512 * n);
                    639:             }
1.1       root      640:         } else {
1.1.1.4   root      641:             if(bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
1.1       root      642:                 return -1;
                    643:         }
                    644:         nb_sectors -= n;
                    645:         sector_num += n;
                    646:         buf += n * 512;
                    647:     }
                    648:     return 0;
                    649: }
                    650: 
1.1.1.5 ! root      651: static int vmdk_write(BlockDriverState *bs, int64_t sector_num,
1.1       root      652:                      const uint8_t *buf, int nb_sectors)
                    653: {
                    654:     BDRVVmdkState *s = bs->opaque;
1.1.1.5 ! root      655:     VmdkMetaData m_data;
1.1.1.4   root      656:     int index_in_cluster, n;
1.1       root      657:     uint64_t cluster_offset;
1.1.1.4   root      658:     static int cid_update = 0;
1.1       root      659: 
1.1.1.5 ! root      660:     if (sector_num > bs->total_sectors) {
        !           661:         fprintf(stderr,
        !           662:                 "(VMDK) Wrong offset: sector_num=0x%" PRIx64
        !           663:                 " total_sectors=0x%" PRIx64 "\n",
        !           664:                 sector_num, bs->total_sectors);
        !           665:         return -1;
        !           666:     }
        !           667: 
1.1       root      668:     while (nb_sectors > 0) {
                    669:         index_in_cluster = sector_num & (s->cluster_sectors - 1);
                    670:         n = s->cluster_sectors - index_in_cluster;
                    671:         if (n > nb_sectors)
                    672:             n = nb_sectors;
1.1.1.5 ! root      673:         cluster_offset = get_cluster_offset(bs, &m_data, sector_num << 9, 1);
1.1       root      674:         if (!cluster_offset)
                    675:             return -1;
1.1.1.5 ! root      676: 
1.1.1.4   root      677:         if (bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
1.1       root      678:             return -1;
1.1.1.5 ! root      679:         if (m_data.valid) {
        !           680:             /* update L2 tables */
        !           681:             if (vmdk_L2update(bs, &m_data) == -1)
        !           682:                 return -1;
        !           683:         }
1.1       root      684:         nb_sectors -= n;
                    685:         sector_num += n;
                    686:         buf += n * 512;
1.1.1.4   root      687: 
                    688:         // update CID on the first write every time the virtual disk is opened
                    689:         if (!cid_update) {
                    690:             vmdk_write_cid(bs, time(NULL));
                    691:             cid_update++;
                    692:         }
1.1       root      693:     }
                    694:     return 0;
                    695: }
                    696: 
                    697: static int vmdk_create(const char *filename, int64_t total_size,
                    698:                        const char *backing_file, int flags)
                    699: {
                    700:     int fd, i;
                    701:     VMDK4Header header;
                    702:     uint32_t tmp, magic, grains, gd_size, gt_size, gt_count;
                    703:     char *desc_template =
                    704:         "# Disk DescriptorFile\n"
                    705:         "version=1\n"
                    706:         "CID=%x\n"
                    707:         "parentCID=ffffffff\n"
                    708:         "createType=\"monolithicSparse\"\n"
                    709:         "\n"
                    710:         "# Extent description\n"
                    711:         "RW %lu SPARSE \"%s\"\n"
                    712:         "\n"
                    713:         "# The Disk Data Base \n"
                    714:         "#DDB\n"
                    715:         "\n"
1.1.1.5 ! root      716:         "ddb.virtualHWVersion = \"%d\"\n"
1.1       root      717:         "ddb.geometry.cylinders = \"%lu\"\n"
                    718:         "ddb.geometry.heads = \"16\"\n"
                    719:         "ddb.geometry.sectors = \"63\"\n"
                    720:         "ddb.adapterType = \"ide\"\n";
                    721:     char desc[1024];
                    722:     const char *real_filename, *temp_str;
                    723: 
                    724:     /* XXX: add support for backing file */
1.1.1.4   root      725:     if (backing_file) {
                    726:         return vmdk_snapshot_create(filename, backing_file);
                    727:     }
1.1       root      728: 
                    729:     fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE,
                    730:               0644);
                    731:     if (fd < 0)
                    732:         return -1;
                    733:     magic = cpu_to_be32(VMDK4_MAGIC);
                    734:     memset(&header, 0, sizeof(header));
                    735:     header.version = cpu_to_le32(1);
                    736:     header.flags = cpu_to_le32(3); /* ?? */
                    737:     header.capacity = cpu_to_le64(total_size);
                    738:     header.granularity = cpu_to_le64(128);
                    739:     header.num_gtes_per_gte = cpu_to_le32(512);
                    740: 
                    741:     grains = (total_size + header.granularity - 1) / header.granularity;
                    742:     gt_size = ((header.num_gtes_per_gte * sizeof(uint32_t)) + 511) >> 9;
                    743:     gt_count = (grains + header.num_gtes_per_gte - 1) / header.num_gtes_per_gte;
                    744:     gd_size = (gt_count * sizeof(uint32_t) + 511) >> 9;
                    745: 
                    746:     header.desc_offset = 1;
                    747:     header.desc_size = 20;
                    748:     header.rgd_offset = header.desc_offset + header.desc_size;
                    749:     header.gd_offset = header.rgd_offset + gd_size + (gt_size * gt_count);
                    750:     header.grain_offset =
                    751:        ((header.gd_offset + gd_size + (gt_size * gt_count) +
                    752:          header.granularity - 1) / header.granularity) *
                    753:         header.granularity;
                    754: 
                    755:     header.desc_offset = cpu_to_le64(header.desc_offset);
                    756:     header.desc_size = cpu_to_le64(header.desc_size);
                    757:     header.rgd_offset = cpu_to_le64(header.rgd_offset);
                    758:     header.gd_offset = cpu_to_le64(header.gd_offset);
                    759:     header.grain_offset = cpu_to_le64(header.grain_offset);
                    760: 
                    761:     header.check_bytes[0] = 0xa;
                    762:     header.check_bytes[1] = 0x20;
                    763:     header.check_bytes[2] = 0xd;
                    764:     header.check_bytes[3] = 0xa;
1.1.1.5 ! root      765: 
        !           766:     /* write all the data */
1.1       root      767:     write(fd, &magic, sizeof(magic));
                    768:     write(fd, &header, sizeof(header));
                    769: 
                    770:     ftruncate(fd, header.grain_offset << 9);
                    771: 
                    772:     /* write grain directory */
                    773:     lseek(fd, le64_to_cpu(header.rgd_offset) << 9, SEEK_SET);
                    774:     for (i = 0, tmp = header.rgd_offset + gd_size;
                    775:          i < gt_count; i++, tmp += gt_size)
                    776:         write(fd, &tmp, sizeof(tmp));
1.1.1.5 ! root      777: 
1.1       root      778:     /* write backup grain directory */
                    779:     lseek(fd, le64_to_cpu(header.gd_offset) << 9, SEEK_SET);
                    780:     for (i = 0, tmp = header.gd_offset + gd_size;
                    781:          i < gt_count; i++, tmp += gt_size)
                    782:         write(fd, &tmp, sizeof(tmp));
                    783: 
                    784:     /* compose the descriptor */
                    785:     real_filename = filename;
                    786:     if ((temp_str = strrchr(real_filename, '\\')) != NULL)
                    787:         real_filename = temp_str + 1;
                    788:     if ((temp_str = strrchr(real_filename, '/')) != NULL)
                    789:         real_filename = temp_str + 1;
                    790:     if ((temp_str = strrchr(real_filename, ':')) != NULL)
                    791:         real_filename = temp_str + 1;
                    792:     sprintf(desc, desc_template, time(NULL), (unsigned long)total_size,
1.1.1.5 ! root      793:             real_filename, (flags & BLOCK_FLAG_COMPAT6 ? 6 : 4), total_size / (63 * 16));
1.1       root      794: 
                    795:     /* write the descriptor */
                    796:     lseek(fd, le64_to_cpu(header.desc_offset) << 9, SEEK_SET);
                    797:     write(fd, desc, strlen(desc));
                    798: 
                    799:     close(fd);
                    800:     return 0;
                    801: }
                    802: 
                    803: static void vmdk_close(BlockDriverState *bs)
                    804: {
                    805:     BDRVVmdkState *s = bs->opaque;
1.1.1.4   root      806: 
1.1       root      807:     qemu_free(s->l1_table);
                    808:     qemu_free(s->l2_cache);
1.1.1.4   root      809:     bdrv_delete(s->hd);
                    810:     // try to close parent image, if exist
                    811:     vmdk_parent_close(s->hd);
1.1       root      812: }
                    813: 
1.1.1.3   root      814: static void vmdk_flush(BlockDriverState *bs)
                    815: {
                    816:     BDRVVmdkState *s = bs->opaque;
1.1.1.4   root      817:     bdrv_flush(s->hd);
1.1.1.3   root      818: }
                    819: 
1.1       root      820: BlockDriver bdrv_vmdk = {
                    821:     "vmdk",
                    822:     sizeof(BDRVVmdkState),
                    823:     vmdk_probe,
                    824:     vmdk_open,
                    825:     vmdk_read,
                    826:     vmdk_write,
                    827:     vmdk_close,
                    828:     vmdk_create,
1.1.1.3   root      829:     vmdk_flush,
1.1       root      830:     vmdk_is_allocated,
                    831: };

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