Annotation of qemu/block-vmdk.c, revision 1.1.1.4

1.1       root        1: /*
                      2:  * Block driver for the VMDK format
                      3:  * 
                      4:  * Copyright (c) 2004 Fabrice Bellard
                      5:  * Copyright (c) 2005 Filip Navara
                      6:  * 
                      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       root       26: #include "vl.h"
                     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       root       78: } BDRVVmdkState;
                     79: 
                     80: static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename)
                     81: {
                     82:     uint32_t magic;
                     83: 
                     84:     if (buf_size < 4)
                     85:         return 0;
                     86:     magic = be32_to_cpu(*(uint32_t *)buf);
                     87:     if (magic == VMDK3_MAGIC ||
                     88:         magic == VMDK4_MAGIC)
                     89:         return 100;
                     90:     else
                     91:         return 0;
                     92: }
                     93: 
1.1.1.4 ! root       94: #define CHECK_CID 1
        !            95: 
        !            96: #define SECTOR_SIZE 512                                
        !            97: #define DESC_SIZE 20*SECTOR_SIZE       // 20 sectors of 512 bytes each
        !            98: #define HEADER_SIZE 512                        // first sector of 512 bytes 
        !            99: 
        !           100: static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent)
1.1       root      101: {
                    102:     BDRVVmdkState *s = bs->opaque;
1.1.1.4 ! root      103:     char desc[DESC_SIZE];
        !           104:     uint32_t cid;
        !           105:     char *p_name, *cid_str; 
        !           106:     size_t cid_str_size;
        !           107: 
        !           108:     /* the descriptor offset = 0x200 */
        !           109:     if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
        !           110:         return 0;
        !           111: 
        !           112:     if (parent) {
        !           113:         cid_str = "parentCID";
        !           114:         cid_str_size = sizeof("parentCID");
        !           115:     } else {
        !           116:         cid_str = "CID";
        !           117:         cid_str_size = sizeof("CID");
        !           118:     }
        !           119: 
        !           120:     if ((p_name = strstr(desc,cid_str)) != 0) {
        !           121:         p_name += cid_str_size;
        !           122:         sscanf(p_name,"%x",&cid);
        !           123:     }
        !           124: 
        !           125:     return cid;
        !           126: }
        !           127: 
        !           128: static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
        !           129: {
        !           130:     BDRVVmdkState *s = bs->opaque;
        !           131:     char desc[DESC_SIZE], tmp_desc[DESC_SIZE];
        !           132:     char *p_name, *tmp_str;
        !           133: 
        !           134:     /* the descriptor offset = 0x200 */
        !           135:     if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
        !           136:         return -1;
        !           137: 
        !           138:     tmp_str = strstr(desc,"parentCID");
        !           139:     strcpy(tmp_desc, tmp_str);
        !           140:     if ((p_name = strstr(desc,"CID")) != 0) {
        !           141:         p_name += sizeof("CID");
        !           142:         sprintf(p_name,"%x\n",cid);
        !           143:         strcat(desc,tmp_desc);
        !           144:     }
        !           145: 
        !           146:     if (bdrv_pwrite(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
        !           147:         return -1;
        !           148:     return 0;
        !           149: }
        !           150: 
        !           151: static int vmdk_is_cid_valid(BlockDriverState *bs)
        !           152: {
        !           153: #ifdef CHECK_CID
        !           154:     BDRVVmdkState *s = bs->opaque;
        !           155:     BlockDriverState *p_bs = s->hd->backing_hd;
        !           156:     uint32_t cur_pcid;
        !           157: 
        !           158:     if (p_bs) {
        !           159:         cur_pcid = vmdk_read_cid(p_bs,0);
        !           160:         if (s->parent_cid != cur_pcid)
        !           161:             // CID not valid
        !           162:             return 0;
        !           163:     }
        !           164: #endif
        !           165:     // CID valid
        !           166:     return 1;
        !           167: }
        !           168: 
        !           169: static int vmdk_snapshot_create(const char *filename, const char *backing_file)
        !           170: {
        !           171:     int snp_fd, p_fd;
        !           172:     uint32_t p_cid;
        !           173:     char *p_name, *gd_buf, *rgd_buf; 
        !           174:     const char *real_filename, *temp_str;
        !           175:     VMDK4Header header;
        !           176:     uint32_t gde_entries, gd_size;
        !           177:     int64_t gd_offset, rgd_offset, capacity, gt_size;
        !           178:     char p_desc[DESC_SIZE], s_desc[DESC_SIZE], hdr[HEADER_SIZE];
        !           179:     char *desc_template =
        !           180:     "# Disk DescriptorFile\n"
        !           181:     "version=1\n"
        !           182:     "CID=%x\n"
        !           183:     "parentCID=%x\n"
        !           184:     "createType=\"monolithicSparse\"\n"
        !           185:     "parentFileNameHint=\"%s\"\n"
        !           186:     "\n"
        !           187:     "# Extent description\n"
        !           188:     "RW %lu SPARSE \"%s\"\n"
        !           189:     "\n"
        !           190:     "# The Disk Data Base \n"
        !           191:     "#DDB\n"
        !           192:     "\n";
        !           193: 
        !           194:     snp_fd = open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, 0644);
        !           195:     if (snp_fd < 0)
        !           196:         return -1;
        !           197:     p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE);
        !           198:     if (p_fd < 0) {
        !           199:         close(snp_fd);
        !           200:         return -1;
        !           201:     }
        !           202: 
        !           203:     /* read the header */
        !           204:     if (lseek(p_fd, 0x0, SEEK_SET) == -1)
        !           205:         goto fail;
        !           206:     if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE)
        !           207:         goto fail;
        !           208: 
        !           209:     /* write the header */
        !           210:     if (lseek(snp_fd, 0x0, SEEK_SET) == -1)
        !           211:         goto fail;
        !           212:     if (write(snp_fd, hdr, HEADER_SIZE) == -1)
        !           213:         goto fail;
        !           214: 
        !           215:     memset(&header, 0, sizeof(header));
        !           216:     memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC
        !           217: 
        !           218:     ftruncate(snp_fd, header.grain_offset << 9);
        !           219:     /* the descriptor offset = 0x200 */
        !           220:     if (lseek(p_fd, 0x200, SEEK_SET) == -1)
        !           221:         goto fail;
        !           222:     if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE)
        !           223:         goto fail;
        !           224: 
        !           225:     if ((p_name = strstr(p_desc,"CID")) != 0) {
        !           226:         p_name += sizeof("CID");
        !           227:         sscanf(p_name,"%x",&p_cid);
        !           228:     }
        !           229: 
        !           230:     real_filename = filename;
        !           231:     if ((temp_str = strrchr(real_filename, '\\')) != NULL)
        !           232:         real_filename = temp_str + 1;
        !           233:     if ((temp_str = strrchr(real_filename, '/')) != NULL)
        !           234:         real_filename = temp_str + 1;
        !           235:     if ((temp_str = strrchr(real_filename, ':')) != NULL)
        !           236:         real_filename = temp_str + 1;
        !           237: 
        !           238:     sprintf(s_desc, desc_template, p_cid, p_cid, backing_file
        !           239:             , (uint32_t)header.capacity, real_filename);
        !           240: 
        !           241:     /* write the descriptor */
        !           242:     if (lseek(snp_fd, 0x200, SEEK_SET) == -1)
        !           243:         goto fail;
        !           244:     if (write(snp_fd, s_desc, strlen(s_desc)) == -1)
        !           245:         goto fail;
1.1       root      246: 
1.1.1.4 ! root      247:     gd_offset = header.gd_offset * SECTOR_SIZE;     // offset of GD table
        !           248:     rgd_offset = header.rgd_offset * SECTOR_SIZE;   // offset of RGD table
        !           249:     capacity = header.capacity * SECTOR_SIZE;       // Extent size
        !           250:     /*
        !           251:      * Each GDE span 32M disk, means:
        !           252:      * 512 GTE per GT, each GTE points to grain
        !           253:      */
        !           254:     gt_size = (int64_t)header.num_gtes_per_gte * header.granularity * SECTOR_SIZE;
        !           255:     if (!gt_size)
        !           256:         goto fail;
        !           257:     gde_entries = (uint32_t)(capacity / gt_size);  // number of gde/rgde 
        !           258:     gd_size = gde_entries * sizeof(uint32_t);
        !           259: 
        !           260:     /* write RGD */
        !           261:     rgd_buf = qemu_malloc(gd_size);
        !           262:     if (!rgd_buf)
        !           263:         goto fail;
        !           264:     if (lseek(p_fd, rgd_offset, SEEK_SET) == -1)
        !           265:         goto fail_rgd;
        !           266:     if (read(p_fd, rgd_buf, gd_size) != gd_size)
        !           267:         goto fail_rgd;
        !           268:     if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1)
        !           269:         goto fail_rgd;
        !           270:     if (write(snp_fd, rgd_buf, gd_size) == -1)
        !           271:         goto fail_rgd;
        !           272:     qemu_free(rgd_buf);
        !           273: 
        !           274:     /* write GD */
        !           275:     gd_buf = qemu_malloc(gd_size);
        !           276:     if (!gd_buf)
        !           277:         goto fail_rgd;
        !           278:     if (lseek(p_fd, gd_offset, SEEK_SET) == -1)
        !           279:         goto fail_gd;
        !           280:     if (read(p_fd, gd_buf, gd_size) != gd_size)
        !           281:         goto fail_gd;
        !           282:     if (lseek(snp_fd, gd_offset, SEEK_SET) == -1)
        !           283:         goto fail_gd;
        !           284:     if (write(snp_fd, gd_buf, gd_size) == -1)
        !           285:         goto fail_gd;
        !           286:     qemu_free(gd_buf);
        !           287: 
        !           288:     close(p_fd);
        !           289:     close(snp_fd);
        !           290:     return 0;
        !           291: 
        !           292:     fail_gd:
        !           293:     qemu_free(gd_buf);
        !           294:     fail_rgd:   
        !           295:     qemu_free(rgd_buf);
        !           296:     fail:
        !           297:     close(p_fd);
        !           298:     close(snp_fd);
        !           299:     return -1;
        !           300: }
        !           301: 
        !           302: static void vmdk_parent_close(BlockDriverState *bs)
        !           303: {
        !           304:     if (bs->backing_hd)
        !           305:         bdrv_close(bs->backing_hd);
        !           306: }
        !           307: 
        !           308: 
        !           309: static int vmdk_parent_open(BlockDriverState *bs, const char * filename)
        !           310: {
        !           311:     BDRVVmdkState *s = bs->opaque;
        !           312:     char *p_name; 
        !           313:     char desc[DESC_SIZE];
        !           314:     char parent_img_name[1024];
        !           315: 
        !           316:     /* the descriptor offset = 0x200 */
        !           317:     if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
        !           318:         return -1;
        !           319: 
        !           320:     if ((p_name = strstr(desc,"parentFileNameHint")) != 0) {
        !           321:         char *end_name;
        !           322:         struct stat file_buf;
        !           323: 
        !           324:         p_name += sizeof("parentFileNameHint") + 1;
        !           325:         if ((end_name = strchr(p_name,'\"')) == 0)
1.1       root      326:             return -1;
1.1.1.4 ! root      327:                 
        !           328:         strncpy(s->hd->backing_file, p_name, end_name - p_name);
        !           329:         if (stat(s->hd->backing_file, &file_buf) != 0) {
        !           330:             path_combine(parent_img_name, sizeof(parent_img_name),
        !           331:                          filename, s->hd->backing_file);
        !           332:         } else {
        !           333:             strcpy(parent_img_name, s->hd->backing_file);
        !           334:         }
        !           335: 
        !           336:         s->hd->backing_hd = bdrv_new("");
        !           337:         if (!s->hd->backing_hd) {
        !           338:             failure:
        !           339:             bdrv_close(s->hd);
        !           340:             return -1;
        !           341:         }
        !           342:         if (bdrv_open(s->hd->backing_hd, parent_img_name, 0) < 0)
        !           343:             goto failure;
1.1       root      344:     }
1.1.1.4 ! root      345: 
        !           346:     return 0;
        !           347: }
        !           348: 
        !           349: static int vmdk_open(BlockDriverState *bs, const char *filename, int flags)
        !           350: {
        !           351:     BDRVVmdkState *s = bs->opaque;
        !           352:     uint32_t magic;
        !           353:     int l1_size, i, ret;
        !           354: 
        !           355:     ret = bdrv_file_open(&s->hd, filename, flags);
        !           356:     if (ret < 0)
        !           357:         return ret;
        !           358:     if (bdrv_pread(s->hd, 0, &magic, sizeof(magic)) != sizeof(magic))
1.1       root      359:         goto fail;
1.1.1.4 ! root      360: 
1.1       root      361:     magic = be32_to_cpu(magic);
                    362:     if (magic == VMDK3_MAGIC) {
                    363:         VMDK3Header header;
1.1.1.4 ! root      364: 
        !           365:         if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
1.1       root      366:             goto fail;
                    367:         s->cluster_sectors = le32_to_cpu(header.granularity);
                    368:         s->l2_size = 1 << 9;
                    369:         s->l1_size = 1 << 6;
                    370:         bs->total_sectors = le32_to_cpu(header.disk_sectors);
                    371:         s->l1_table_offset = le32_to_cpu(header.l1dir_offset) << 9;
                    372:         s->l1_backup_table_offset = 0;
                    373:         s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
                    374:     } else if (magic == VMDK4_MAGIC) {
                    375:         VMDK4Header header;
1.1.1.4 ! root      376: 
        !           377:         if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
1.1       root      378:             goto fail;
1.1.1.2   root      379:         bs->total_sectors = le64_to_cpu(header.capacity);
                    380:         s->cluster_sectors = le64_to_cpu(header.granularity);
1.1       root      381:         s->l2_size = le32_to_cpu(header.num_gtes_per_gte);
                    382:         s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
                    383:         if (s->l1_entry_sectors <= 0)
                    384:             goto fail;
                    385:         s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1) 
                    386:             / s->l1_entry_sectors;
                    387:         s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9;
                    388:         s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
1.1.1.4 ! root      389: 
        !           390:         // try to open parent images, if exist
        !           391:         if (vmdk_parent_open(bs, filename) != 0)
        !           392:             goto fail;
        !           393:         // write the CID once after the image creation
        !           394:         s->parent_cid = vmdk_read_cid(bs,1);
1.1       root      395:     } else {
                    396:         goto fail;
                    397:     }
1.1.1.4 ! root      398: 
1.1       root      399:     /* read the L1 table */
                    400:     l1_size = s->l1_size * sizeof(uint32_t);
                    401:     s->l1_table = qemu_malloc(l1_size);
                    402:     if (!s->l1_table)
                    403:         goto fail;
1.1.1.4 ! root      404:     if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, l1_size) != l1_size)
1.1       root      405:         goto fail;
                    406:     for(i = 0; i < s->l1_size; i++) {
                    407:         le32_to_cpus(&s->l1_table[i]);
                    408:     }
                    409: 
                    410:     if (s->l1_backup_table_offset) {
                    411:         s->l1_backup_table = qemu_malloc(l1_size);
                    412:         if (!s->l1_backup_table)
                    413:             goto fail;
1.1.1.4 ! root      414:         if (bdrv_pread(s->hd, s->l1_backup_table_offset, s->l1_backup_table, l1_size) != l1_size)
1.1       root      415:             goto fail;
                    416:         for(i = 0; i < s->l1_size; i++) {
                    417:             le32_to_cpus(&s->l1_backup_table[i]);
                    418:         }
                    419:     }
                    420: 
                    421:     s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t));
                    422:     if (!s->l2_cache)
                    423:         goto fail;
                    424:     return 0;
                    425:  fail:
                    426:     qemu_free(s->l1_backup_table);
                    427:     qemu_free(s->l1_table);
                    428:     qemu_free(s->l2_cache);
1.1.1.4 ! root      429:     bdrv_delete(s->hd);
1.1       root      430:     return -1;
                    431: }
                    432: 
1.1.1.4 ! root      433: static uint64_t get_cluster_offset(BlockDriverState *bs, uint64_t offset, int allocate);
        !           434: 
        !           435: static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset,
        !           436:                              uint64_t offset, int allocate)
        !           437: {
        !           438:     uint64_t parent_cluster_offset;
        !           439:     BDRVVmdkState *s = bs->opaque;
        !           440:     uint8_t  whole_grain[s->cluster_sectors*512];        // 128 sectors * 512 bytes each = grain size 64KB
        !           441: 
        !           442:     // we will be here if it's first write on non-exist grain(cluster).
        !           443:     // try to read from parent image, if exist
        !           444:     if (s->hd->backing_hd) {
        !           445:         BDRVVmdkState *ps = s->hd->backing_hd->opaque;
        !           446: 
        !           447:         if (!vmdk_is_cid_valid(bs))
        !           448:             return -1;
        !           449:         parent_cluster_offset = get_cluster_offset(s->hd->backing_hd, offset, allocate);
        !           450:         if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) != 
        !           451:                                                                             ps->cluster_sectors*512)
        !           452:             return -1;
        !           453: 
        !           454:         if (bdrv_pwrite(s->hd, cluster_offset << 9, whole_grain, sizeof(whole_grain)) != 
        !           455:                                                                             sizeof(whole_grain))
        !           456:             return -1;
        !           457:     }
        !           458:     return 0;
        !           459: }
        !           460: 
1.1       root      461: static uint64_t get_cluster_offset(BlockDriverState *bs,
                    462:                                    uint64_t offset, int allocate)
                    463: {
                    464:     BDRVVmdkState *s = bs->opaque;
                    465:     unsigned int l1_index, l2_offset, l2_index;
                    466:     int min_index, i, j;
                    467:     uint32_t min_count, *l2_table, tmp;
                    468:     uint64_t cluster_offset;
                    469:     
                    470:     l1_index = (offset >> 9) / s->l1_entry_sectors;
                    471:     if (l1_index >= s->l1_size)
                    472:         return 0;
                    473:     l2_offset = s->l1_table[l1_index];
                    474:     if (!l2_offset)
                    475:         return 0;
                    476:     for(i = 0; i < L2_CACHE_SIZE; i++) {
                    477:         if (l2_offset == s->l2_cache_offsets[i]) {
                    478:             /* increment the hit count */
                    479:             if (++s->l2_cache_counts[i] == 0xffffffff) {
                    480:                 for(j = 0; j < L2_CACHE_SIZE; j++) {
                    481:                     s->l2_cache_counts[j] >>= 1;
                    482:                 }
                    483:             }
                    484:             l2_table = s->l2_cache + (i * s->l2_size);
                    485:             goto found;
                    486:         }
                    487:     }
                    488:     /* not found: load a new entry in the least used one */
                    489:     min_index = 0;
                    490:     min_count = 0xffffffff;
                    491:     for(i = 0; i < L2_CACHE_SIZE; i++) {
                    492:         if (s->l2_cache_counts[i] < min_count) {
                    493:             min_count = s->l2_cache_counts[i];
                    494:             min_index = i;
                    495:         }
                    496:     }
                    497:     l2_table = s->l2_cache + (min_index * s->l2_size);
1.1.1.4 ! root      498:     if (bdrv_pread(s->hd, (int64_t)l2_offset * 512, l2_table, s->l2_size * sizeof(uint32_t)) != 
        !           499:                                                                         s->l2_size * sizeof(uint32_t))
1.1       root      500:         return 0;
1.1.1.4 ! root      501: 
1.1       root      502:     s->l2_cache_offsets[min_index] = l2_offset;
                    503:     s->l2_cache_counts[min_index] = 1;
                    504:  found:
                    505:     l2_index = ((offset >> 9) / s->cluster_sectors) % s->l2_size;
                    506:     cluster_offset = le32_to_cpu(l2_table[l2_index]);
                    507:     if (!cluster_offset) {
1.1.1.4 ! root      508:         struct stat file_buf;
        !           509: 
1.1       root      510:         if (!allocate)
                    511:             return 0;
1.1.1.4 ! root      512:         stat(s->hd->filename, &file_buf);
        !           513:         cluster_offset = file_buf.st_size;
        !           514:         bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9));
        !           515: 
1.1       root      516:         cluster_offset >>= 9;
                    517:         /* update L2 table */
                    518:         tmp = cpu_to_le32(cluster_offset);
                    519:         l2_table[l2_index] = tmp;
1.1.1.4 ! root      520:         if (bdrv_pwrite(s->hd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), 
        !           521:                         &tmp, sizeof(tmp)) != sizeof(tmp))
1.1       root      522:             return 0;
                    523:         /* update backup L2 table */
                    524:         if (s->l1_backup_table_offset != 0) {
                    525:             l2_offset = s->l1_backup_table[l1_index];
1.1.1.4 ! root      526:             if (bdrv_pwrite(s->hd, ((int64_t)l2_offset * 512) + (l2_index * sizeof(tmp)), 
        !           527:                             &tmp, sizeof(tmp)) != sizeof(tmp))
1.1       root      528:                 return 0;
                    529:         }
1.1.1.4 ! root      530: 
        !           531:         if (get_whole_cluster(bs, cluster_offset, offset, allocate) == -1)
        !           532:             return 0;
1.1       root      533:     }
                    534:     cluster_offset <<= 9;
                    535:     return cluster_offset;
                    536: }
                    537: 
                    538: static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num, 
                    539:                              int nb_sectors, int *pnum)
                    540: {
                    541:     BDRVVmdkState *s = bs->opaque;
                    542:     int index_in_cluster, n;
                    543:     uint64_t cluster_offset;
                    544: 
                    545:     cluster_offset = get_cluster_offset(bs, sector_num << 9, 0);
                    546:     index_in_cluster = sector_num % s->cluster_sectors;
                    547:     n = s->cluster_sectors - index_in_cluster;
                    548:     if (n > nb_sectors)
                    549:         n = nb_sectors;
                    550:     *pnum = n;
                    551:     return (cluster_offset != 0);
                    552: }
                    553: 
                    554: static int vmdk_read(BlockDriverState *bs, int64_t sector_num, 
                    555:                     uint8_t *buf, int nb_sectors)
                    556: {
                    557:     BDRVVmdkState *s = bs->opaque;
1.1.1.4 ! root      558:     int index_in_cluster, n, ret;
1.1       root      559:     uint64_t cluster_offset;
1.1.1.4 ! root      560: 
1.1       root      561:     while (nb_sectors > 0) {
                    562:         cluster_offset = get_cluster_offset(bs, sector_num << 9, 0);
                    563:         index_in_cluster = sector_num % s->cluster_sectors;
                    564:         n = s->cluster_sectors - index_in_cluster;
                    565:         if (n > nb_sectors)
                    566:             n = nb_sectors;
                    567:         if (!cluster_offset) {
1.1.1.4 ! root      568:             // try to read from parent image, if exist
        !           569:             if (s->hd->backing_hd) {
        !           570:                 if (!vmdk_is_cid_valid(bs))
        !           571:                     return -1;
        !           572:                 ret = bdrv_read(s->hd->backing_hd, sector_num, buf, n);
        !           573:                 if (ret < 0)
        !           574:                     return -1;
        !           575:             } else {
        !           576:                 memset(buf, 0, 512 * n);
        !           577:             }
1.1       root      578:         } else {
1.1.1.4 ! root      579:             if(bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
1.1       root      580:                 return -1;
                    581:         }
                    582:         nb_sectors -= n;
                    583:         sector_num += n;
                    584:         buf += n * 512;
                    585:     }
                    586:     return 0;
                    587: }
                    588: 
                    589: static int vmdk_write(BlockDriverState *bs, int64_t sector_num, 
                    590:                      const uint8_t *buf, int nb_sectors)
                    591: {
                    592:     BDRVVmdkState *s = bs->opaque;
1.1.1.4 ! root      593:     int index_in_cluster, n;
1.1       root      594:     uint64_t cluster_offset;
1.1.1.4 ! root      595:     static int cid_update = 0;
1.1       root      596: 
                    597:     while (nb_sectors > 0) {
                    598:         index_in_cluster = sector_num & (s->cluster_sectors - 1);
                    599:         n = s->cluster_sectors - index_in_cluster;
                    600:         if (n > nb_sectors)
                    601:             n = nb_sectors;
                    602:         cluster_offset = get_cluster_offset(bs, sector_num << 9, 1);
                    603:         if (!cluster_offset)
                    604:             return -1;
1.1.1.4 ! root      605:         if (bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
1.1       root      606:             return -1;
                    607:         nb_sectors -= n;
                    608:         sector_num += n;
                    609:         buf += n * 512;
1.1.1.4 ! root      610: 
        !           611:         // update CID on the first write every time the virtual disk is opened
        !           612:         if (!cid_update) {
        !           613:             vmdk_write_cid(bs, time(NULL));
        !           614:             cid_update++;
        !           615:         }
1.1       root      616:     }
                    617:     return 0;
                    618: }
                    619: 
                    620: static int vmdk_create(const char *filename, int64_t total_size,
                    621:                        const char *backing_file, int flags)
                    622: {
                    623:     int fd, i;
                    624:     VMDK4Header header;
                    625:     uint32_t tmp, magic, grains, gd_size, gt_size, gt_count;
                    626:     char *desc_template =
                    627:         "# Disk DescriptorFile\n"
                    628:         "version=1\n"
                    629:         "CID=%x\n"
                    630:         "parentCID=ffffffff\n"
                    631:         "createType=\"monolithicSparse\"\n"
                    632:         "\n"
                    633:         "# Extent description\n"
                    634:         "RW %lu SPARSE \"%s\"\n"
                    635:         "\n"
                    636:         "# The Disk Data Base \n"
                    637:         "#DDB\n"
                    638:         "\n"
1.1.1.4 ! root      639:         "ddb.virtualHWVersion = \"4\"\n"
1.1       root      640:         "ddb.geometry.cylinders = \"%lu\"\n"
                    641:         "ddb.geometry.heads = \"16\"\n"
                    642:         "ddb.geometry.sectors = \"63\"\n"
                    643:         "ddb.adapterType = \"ide\"\n";
                    644:     char desc[1024];
                    645:     const char *real_filename, *temp_str;
                    646: 
                    647:     /* XXX: add support for backing file */
1.1.1.4 ! root      648:     if (backing_file) {
        !           649:         return vmdk_snapshot_create(filename, backing_file);
        !           650:     }
1.1       root      651: 
                    652:     fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE,
                    653:               0644);
                    654:     if (fd < 0)
                    655:         return -1;
                    656:     magic = cpu_to_be32(VMDK4_MAGIC);
                    657:     memset(&header, 0, sizeof(header));
                    658:     header.version = cpu_to_le32(1);
                    659:     header.flags = cpu_to_le32(3); /* ?? */
                    660:     header.capacity = cpu_to_le64(total_size);
                    661:     header.granularity = cpu_to_le64(128);
                    662:     header.num_gtes_per_gte = cpu_to_le32(512);
                    663: 
                    664:     grains = (total_size + header.granularity - 1) / header.granularity;
                    665:     gt_size = ((header.num_gtes_per_gte * sizeof(uint32_t)) + 511) >> 9;
                    666:     gt_count = (grains + header.num_gtes_per_gte - 1) / header.num_gtes_per_gte;
                    667:     gd_size = (gt_count * sizeof(uint32_t) + 511) >> 9;
                    668: 
                    669:     header.desc_offset = 1;
                    670:     header.desc_size = 20;
                    671:     header.rgd_offset = header.desc_offset + header.desc_size;
                    672:     header.gd_offset = header.rgd_offset + gd_size + (gt_size * gt_count);
                    673:     header.grain_offset =
                    674:        ((header.gd_offset + gd_size + (gt_size * gt_count) +
                    675:          header.granularity - 1) / header.granularity) *
                    676:         header.granularity;
                    677: 
                    678:     header.desc_offset = cpu_to_le64(header.desc_offset);
                    679:     header.desc_size = cpu_to_le64(header.desc_size);
                    680:     header.rgd_offset = cpu_to_le64(header.rgd_offset);
                    681:     header.gd_offset = cpu_to_le64(header.gd_offset);
                    682:     header.grain_offset = cpu_to_le64(header.grain_offset);
                    683: 
                    684:     header.check_bytes[0] = 0xa;
                    685:     header.check_bytes[1] = 0x20;
                    686:     header.check_bytes[2] = 0xd;
                    687:     header.check_bytes[3] = 0xa;
                    688:     
                    689:     /* write all the data */    
                    690:     write(fd, &magic, sizeof(magic));
                    691:     write(fd, &header, sizeof(header));
                    692: 
                    693:     ftruncate(fd, header.grain_offset << 9);
                    694: 
                    695:     /* write grain directory */
                    696:     lseek(fd, le64_to_cpu(header.rgd_offset) << 9, SEEK_SET);
                    697:     for (i = 0, tmp = header.rgd_offset + gd_size;
                    698:          i < gt_count; i++, tmp += gt_size)
                    699:         write(fd, &tmp, sizeof(tmp));
                    700:    
                    701:     /* write backup grain directory */
                    702:     lseek(fd, le64_to_cpu(header.gd_offset) << 9, SEEK_SET);
                    703:     for (i = 0, tmp = header.gd_offset + gd_size;
                    704:          i < gt_count; i++, tmp += gt_size)
                    705:         write(fd, &tmp, sizeof(tmp));
                    706: 
                    707:     /* compose the descriptor */
                    708:     real_filename = filename;
                    709:     if ((temp_str = strrchr(real_filename, '\\')) != NULL)
                    710:         real_filename = temp_str + 1;
                    711:     if ((temp_str = strrchr(real_filename, '/')) != NULL)
                    712:         real_filename = temp_str + 1;
                    713:     if ((temp_str = strrchr(real_filename, ':')) != NULL)
                    714:         real_filename = temp_str + 1;
                    715:     sprintf(desc, desc_template, time(NULL), (unsigned long)total_size,
                    716:             real_filename, total_size / (63 * 16));
                    717: 
                    718:     /* write the descriptor */
                    719:     lseek(fd, le64_to_cpu(header.desc_offset) << 9, SEEK_SET);
                    720:     write(fd, desc, strlen(desc));
                    721: 
                    722:     close(fd);
                    723:     return 0;
                    724: }
                    725: 
                    726: static void vmdk_close(BlockDriverState *bs)
                    727: {
                    728:     BDRVVmdkState *s = bs->opaque;
1.1.1.4 ! root      729: 
1.1       root      730:     qemu_free(s->l1_table);
                    731:     qemu_free(s->l2_cache);
1.1.1.4 ! root      732:     bdrv_delete(s->hd);
        !           733:     // try to close parent image, if exist
        !           734:     vmdk_parent_close(s->hd);
1.1       root      735: }
                    736: 
1.1.1.3   root      737: static void vmdk_flush(BlockDriverState *bs)
                    738: {
                    739:     BDRVVmdkState *s = bs->opaque;
1.1.1.4 ! root      740:     bdrv_flush(s->hd);
1.1.1.3   root      741: }
                    742: 
1.1       root      743: BlockDriver bdrv_vmdk = {
                    744:     "vmdk",
                    745:     sizeof(BDRVVmdkState),
                    746:     vmdk_probe,
                    747:     vmdk_open,
                    748:     vmdk_read,
                    749:     vmdk_write,
                    750:     vmdk_close,
                    751:     vmdk_create,
1.1.1.3   root      752:     vmdk_flush,
1.1       root      753:     vmdk_is_allocated,
                    754: };

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