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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 */
25
26 #include "qemu-common.h"
27 #include "block_int.h"
28 #include "module.h"
29
30 #define VMDK3_MAGIC (('C' << 24) | ('O' << 16) | ('W' << 8) | 'D')
31 #define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V')
32
33 typedef struct {
34 uint32_t version;
35 uint32_t flags;
36 uint32_t disk_sectors;
37 uint32_t granularity;
38 uint32_t l1dir_offset;
39 uint32_t l1dir_size;
40 uint32_t file_sectors;
41 uint32_t cylinders;
42 uint32_t heads;
43 uint32_t sectors_per_track;
44 } VMDK3Header;
45
46 typedef struct {
47 uint32_t version;
48 uint32_t flags;
49 int64_t capacity;
50 int64_t granularity;
51 int64_t desc_offset;
52 int64_t desc_size;
53 int32_t num_gtes_per_gte;
54 int64_t rgd_offset;
55 int64_t gd_offset;
56 int64_t grain_offset;
57 char filler[1];
58 char check_bytes[4];
59 } __attribute__((packed)) VMDK4Header;
60
61 #define L2_CACHE_SIZE 16
62
63 typedef struct BDRVVmdkState {
64 BlockDriverState *hd;
65 int64_t l1_table_offset;
66 int64_t l1_backup_table_offset;
67 uint32_t *l1_table;
68 uint32_t *l1_backup_table;
69 unsigned int l1_size;
70 uint32_t l1_entry_sectors;
71
72 unsigned int l2_size;
73 uint32_t *l2_cache;
74 uint32_t l2_cache_offsets[L2_CACHE_SIZE];
75 uint32_t l2_cache_counts[L2_CACHE_SIZE];
76
77 unsigned int cluster_sectors;
78 uint32_t parent_cid;
79 int is_parent;
80 } BDRVVmdkState;
81
82 typedef struct VmdkMetaData {
83 uint32_t offset;
84 unsigned int l1_index;
85 unsigned int l2_index;
86 unsigned int l2_offset;
87 int valid;
88 } VmdkMetaData;
89
90 typedef struct ActiveBDRVState{
91 BlockDriverState *hd; // active image handler
92 uint64_t cluster_offset; // current write offset
93 }ActiveBDRVState;
94
95 static ActiveBDRVState activeBDRV;
96
97
98 static int vmdk_probe(const uint8_t *buf, int buf_size, const char *filename)
99 {
100 uint32_t magic;
101
102 if (buf_size < 4)
103 return 0;
104 magic = be32_to_cpu(*(uint32_t *)buf);
105 if (magic == VMDK3_MAGIC ||
106 magic == VMDK4_MAGIC)
107 return 100;
108 else
109 return 0;
110 }
111
112 #define CHECK_CID 1
113
114 #define SECTOR_SIZE 512
115 #define DESC_SIZE 20*SECTOR_SIZE // 20 sectors of 512 bytes each
116 #define HEADER_SIZE 512 // first sector of 512 bytes
117
118 static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent)
119 {
120 BDRVVmdkState *s = bs->opaque;
121 char desc[DESC_SIZE];
122 uint32_t cid;
123 const char *p_name, *cid_str;
124 size_t cid_str_size;
125
126 /* the descriptor offset = 0x200 */
127 if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
128 return 0;
129
130 if (parent) {
131 cid_str = "parentCID";
132 cid_str_size = sizeof("parentCID");
133 } else {
134 cid_str = "CID";
135 cid_str_size = sizeof("CID");
136 }
137
138 if ((p_name = strstr(desc,cid_str)) != NULL) {
139 p_name += cid_str_size;
140 sscanf(p_name,"%x",&cid);
141 }
142
143 return cid;
144 }
145
146 static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid)
147 {
148 BDRVVmdkState *s = bs->opaque;
149 char desc[DESC_SIZE], tmp_desc[DESC_SIZE];
150 char *p_name, *tmp_str;
151
152 /* the descriptor offset = 0x200 */
153 if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
154 return -1;
155
156 tmp_str = strstr(desc,"parentCID");
157 pstrcpy(tmp_desc, sizeof(tmp_desc), tmp_str);
158 if ((p_name = strstr(desc,"CID")) != NULL) {
159 p_name += sizeof("CID");
160 snprintf(p_name, sizeof(desc) - (p_name - desc), "%x\n", cid);
161 pstrcat(desc, sizeof(desc), tmp_desc);
162 }
163
164 if (bdrv_pwrite(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
165 return -1;
166 return 0;
167 }
168
169 static int vmdk_is_cid_valid(BlockDriverState *bs)
170 {
171 #ifdef CHECK_CID
172 BDRVVmdkState *s = bs->opaque;
173 BlockDriverState *p_bs = bs->backing_hd;
174 uint32_t cur_pcid;
175
176 if (p_bs) {
177 cur_pcid = vmdk_read_cid(p_bs,0);
178 if (s->parent_cid != cur_pcid)
179 // CID not valid
180 return 0;
181 }
182 #endif
183 // CID valid
184 return 1;
185 }
186
187 static int vmdk_snapshot_create(const char *filename, const char *backing_file)
188 {
189 int snp_fd, p_fd;
190 uint32_t p_cid;
191 char *p_name, *gd_buf, *rgd_buf;
192 const char *real_filename, *temp_str;
193 VMDK4Header header;
194 uint32_t gde_entries, gd_size;
195 int64_t gd_offset, rgd_offset, capacity, gt_size;
196 char p_desc[DESC_SIZE], s_desc[DESC_SIZE], hdr[HEADER_SIZE];
197 static const char desc_template[] =
198 "# Disk DescriptorFile\n"
199 "version=1\n"
200 "CID=%x\n"
201 "parentCID=%x\n"
202 "createType=\"monolithicSparse\"\n"
203 "parentFileNameHint=\"%s\"\n"
204 "\n"
205 "# Extent description\n"
206 "RW %u SPARSE \"%s\"\n"
207 "\n"
208 "# The Disk Data Base \n"
209 "#DDB\n"
210 "\n";
211
212 snp_fd = open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, 0644);
213 if (snp_fd < 0)
214 return -1;
215 p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE);
216 if (p_fd < 0) {
217 close(snp_fd);
218 return -1;
219 }
220
221 /* read the header */
222 if (lseek(p_fd, 0x0, SEEK_SET) == -1)
223 goto fail;
224 if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE)
225 goto fail;
226
227 /* write the header */
228 if (lseek(snp_fd, 0x0, SEEK_SET) == -1)
229 goto fail;
230 if (write(snp_fd, hdr, HEADER_SIZE) == -1)
231 goto fail;
232
233 memset(&header, 0, sizeof(header));
234 memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC
235
236 ftruncate(snp_fd, header.grain_offset << 9);
237 /* the descriptor offset = 0x200 */
238 if (lseek(p_fd, 0x200, SEEK_SET) == -1)
239 goto fail;
240 if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE)
241 goto fail;
242
243 if ((p_name = strstr(p_desc,"CID")) != NULL) {
244 p_name += sizeof("CID");
245 sscanf(p_name,"%x",&p_cid);
246 }
247
248 real_filename = filename;
249 if ((temp_str = strrchr(real_filename, '\\')) != NULL)
250 real_filename = temp_str + 1;
251 if ((temp_str = strrchr(real_filename, '/')) != NULL)
252 real_filename = temp_str + 1;
253 if ((temp_str = strrchr(real_filename, ':')) != NULL)
254 real_filename = temp_str + 1;
255
256 snprintf(s_desc, sizeof(s_desc), desc_template, p_cid, p_cid, backing_file,
257 (uint32_t)header.capacity, real_filename);
258
259 /* write the descriptor */
260 if (lseek(snp_fd, 0x200, SEEK_SET) == -1)
261 goto fail;
262 if (write(snp_fd, s_desc, strlen(s_desc)) == -1)
263 goto fail;
264
265 gd_offset = header.gd_offset * SECTOR_SIZE; // offset of GD table
266 rgd_offset = header.rgd_offset * SECTOR_SIZE; // offset of RGD table
267 capacity = header.capacity * SECTOR_SIZE; // Extent size
268 /*
269 * Each GDE span 32M disk, means:
270 * 512 GTE per GT, each GTE points to grain
271 */
272 gt_size = (int64_t)header.num_gtes_per_gte * header.granularity * SECTOR_SIZE;
273 if (!gt_size)
274 goto fail;
275 gde_entries = (uint32_t)(capacity / gt_size); // number of gde/rgde
276 gd_size = gde_entries * sizeof(uint32_t);
277
278 /* write RGD */
279 rgd_buf = qemu_malloc(gd_size);
280 if (lseek(p_fd, rgd_offset, SEEK_SET) == -1)
281 goto fail_rgd;
282 if (read(p_fd, rgd_buf, gd_size) != gd_size)
283 goto fail_rgd;
284 if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1)
285 goto fail_rgd;
286 if (write(snp_fd, rgd_buf, gd_size) == -1)
287 goto fail_rgd;
288 qemu_free(rgd_buf);
289
290 /* write GD */
291 gd_buf = qemu_malloc(gd_size);
292 if (lseek(p_fd, gd_offset, SEEK_SET) == -1)
293 goto fail_gd;
294 if (read(p_fd, gd_buf, gd_size) != gd_size)
295 goto fail_gd;
296 if (lseek(snp_fd, gd_offset, SEEK_SET) == -1)
297 goto fail_gd;
298 if (write(snp_fd, gd_buf, gd_size) == -1)
299 goto fail_gd;
300 qemu_free(gd_buf);
301
302 close(p_fd);
303 close(snp_fd);
304 return 0;
305
306 fail_gd:
307 qemu_free(gd_buf);
308 fail_rgd:
309 qemu_free(rgd_buf);
310 fail:
311 close(p_fd);
312 close(snp_fd);
313 return -1;
314 }
315
316 static void vmdk_parent_close(BlockDriverState *bs)
317 {
318 if (bs->backing_hd)
319 bdrv_close(bs->backing_hd);
320 }
321
322 static int parent_open = 0;
323 static int vmdk_parent_open(BlockDriverState *bs, const char * filename)
324 {
325 BDRVVmdkState *s = bs->opaque;
326 char *p_name;
327 char desc[DESC_SIZE];
328 char parent_img_name[1024];
329
330 /* the descriptor offset = 0x200 */
331 if (bdrv_pread(s->hd, 0x200, desc, DESC_SIZE) != DESC_SIZE)
332 return -1;
333
334 if ((p_name = strstr(desc,"parentFileNameHint")) != NULL) {
335 char *end_name;
336 struct stat file_buf;
337
338 p_name += sizeof("parentFileNameHint") + 1;
339 if ((end_name = strchr(p_name,'\"')) == NULL)
340 return -1;
341 if ((end_name - p_name) > sizeof (bs->backing_file) - 1)
342 return -1;
343
344 pstrcpy(bs->backing_file, end_name - p_name + 1, p_name);
345 if (stat(bs->backing_file, &file_buf) != 0) {
346 path_combine(parent_img_name, sizeof(parent_img_name),
347 filename, bs->backing_file);
348 } else {
349 pstrcpy(parent_img_name, sizeof(parent_img_name),
350 bs->backing_file);
351 }
352
353 bs->backing_hd = bdrv_new("");
354 if (!bs->backing_hd) {
355 failure:
356 bdrv_close(s->hd);
357 return -1;
358 }
359 parent_open = 1;
360 if (bdrv_open(bs->backing_hd, parent_img_name, BDRV_O_RDONLY) < 0)
361 goto failure;
362 parent_open = 0;
363 }
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
374 if (parent_open)
375 // Parent must be opened as RO.
376 flags = BDRV_O_RDONLY;
377
378 ret = bdrv_file_open(&s->hd, filename, flags);
379 if (ret < 0)
380 return ret;
381 if (bdrv_pread(s->hd, 0, &magic, sizeof(magic)) != sizeof(magic))
382 goto fail;
383
384 magic = be32_to_cpu(magic);
385 if (magic == VMDK3_MAGIC) {
386 VMDK3Header header;
387
388 if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
389 goto fail;
390 s->cluster_sectors = le32_to_cpu(header.granularity);
391 s->l2_size = 1 << 9;
392 s->l1_size = 1 << 6;
393 bs->total_sectors = le32_to_cpu(header.disk_sectors);
394 s->l1_table_offset = le32_to_cpu(header.l1dir_offset) << 9;
395 s->l1_backup_table_offset = 0;
396 s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
397 } else if (magic == VMDK4_MAGIC) {
398 VMDK4Header header;
399
400 if (bdrv_pread(s->hd, sizeof(magic), &header, sizeof(header)) != sizeof(header))
401 goto fail;
402 bs->total_sectors = le64_to_cpu(header.capacity);
403 s->cluster_sectors = le64_to_cpu(header.granularity);
404 s->l2_size = le32_to_cpu(header.num_gtes_per_gte);
405 s->l1_entry_sectors = s->l2_size * s->cluster_sectors;
406 if (s->l1_entry_sectors <= 0)
407 goto fail;
408 s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1)
409 / s->l1_entry_sectors;
410 s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9;
411 s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
412
413 if (parent_open)
414 s->is_parent = 1;
415 else
416 s->is_parent = 0;
417
418 // try to open parent images, if exist
419 if (vmdk_parent_open(bs, filename) != 0)
420 goto fail;
421 // write the CID once after the image creation
422 s->parent_cid = vmdk_read_cid(bs,1);
423 } else {
424 goto fail;
425 }
426
427 /* read the L1 table */
428 l1_size = s->l1_size * sizeof(uint32_t);
429 s->l1_table = qemu_malloc(l1_size);
430 if (bdrv_pread(s->hd, s->l1_table_offset, s->l1_table, l1_size) != l1_size)
431 goto fail;
432 for(i = 0; i < s->l1_size; i++) {
433 le32_to_cpus(&s->l1_table[i]);
434 }
435
436 if (s->l1_backup_table_offset) {
437 s->l1_backup_table = qemu_malloc(l1_size);
438 if (bdrv_pread(s->hd, s->l1_backup_table_offset, s->l1_backup_table, l1_size) != l1_size)
439 goto fail;
440 for(i = 0; i < s->l1_size; i++) {
441 le32_to_cpus(&s->l1_backup_table[i]);
442 }
443 }
444
445 s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t));
446 return 0;
447 fail:
448 qemu_free(s->l1_backup_table);
449 qemu_free(s->l1_table);
450 qemu_free(s->l2_cache);
451 bdrv_delete(s->hd);
452 return -1;
453 }
454
455 static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
456 uint64_t offset, int allocate);
457
458 static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset,
459 uint64_t offset, int allocate)
460 {
461 uint64_t parent_cluster_offset;
462 BDRVVmdkState *s = bs->opaque;
463 uint8_t whole_grain[s->cluster_sectors*512]; // 128 sectors * 512 bytes each = grain size 64KB
464
465 // we will be here if it's first write on non-exist grain(cluster).
466 // try to read from parent image, if exist
467 if (bs->backing_hd) {
468 BDRVVmdkState *ps = bs->backing_hd->opaque;
469
470 if (!vmdk_is_cid_valid(bs))
471 return -1;
472
473 parent_cluster_offset = get_cluster_offset(bs->backing_hd, NULL,
474 offset, allocate);
475
476 if (parent_cluster_offset) {
477 BDRVVmdkState *act_s = activeBDRV.hd->opaque;
478
479 if (bdrv_pread(ps->hd, parent_cluster_offset, whole_grain, ps->cluster_sectors*512) != ps->cluster_sectors*512)
480 return -1;
481
482 //Write grain only into the active image
483 if (bdrv_pwrite(act_s->hd, activeBDRV.cluster_offset << 9, whole_grain, sizeof(whole_grain)) != sizeof(whole_grain))
484 return -1;
485 }
486 }
487 return 0;
488 }
489
490 static int vmdk_L2update(BlockDriverState *bs, VmdkMetaData *m_data)
491 {
492 BDRVVmdkState *s = bs->opaque;
493
494 /* update L2 table */
495 if (bdrv_pwrite(s->hd, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(m_data->offset)),
496 &(m_data->offset), sizeof(m_data->offset)) != sizeof(m_data->offset))
497 return -1;
498 /* update backup L2 table */
499 if (s->l1_backup_table_offset != 0) {
500 m_data->l2_offset = s->l1_backup_table[m_data->l1_index];
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 }
505
506 return 0;
507 }
508
509 static uint64_t get_cluster_offset(BlockDriverState *bs, VmdkMetaData *m_data,
510 uint64_t offset, int allocate)
511 {
512 BDRVVmdkState *s = bs->opaque;
513 unsigned int l1_index, l2_offset, l2_index;
514 int min_index, i, j;
515 uint32_t min_count, *l2_table, tmp = 0;
516 uint64_t cluster_offset;
517
518 if (m_data)
519 m_data->valid = 0;
520
521 l1_index = (offset >> 9) / s->l1_entry_sectors;
522 if (l1_index >= s->l1_size)
523 return 0;
524 l2_offset = s->l1_table[l1_index];
525 if (!l2_offset)
526 return 0;
527 for(i = 0; i < L2_CACHE_SIZE; i++) {
528 if (l2_offset == s->l2_cache_offsets[i]) {
529 /* increment the hit count */
530 if (++s->l2_cache_counts[i] == 0xffffffff) {
531 for(j = 0; j < L2_CACHE_SIZE; j++) {
532 s->l2_cache_counts[j] >>= 1;
533 }
534 }
535 l2_table = s->l2_cache + (i * s->l2_size);
536 goto found;
537 }
538 }
539 /* not found: load a new entry in the least used one */
540 min_index = 0;
541 min_count = 0xffffffff;
542 for(i = 0; i < L2_CACHE_SIZE; i++) {
543 if (s->l2_cache_counts[i] < min_count) {
544 min_count = s->l2_cache_counts[i];
545 min_index = i;
546 }
547 }
548 l2_table = s->l2_cache + (min_index * s->l2_size);
549 if (bdrv_pread(s->hd, (int64_t)l2_offset * 512, l2_table, s->l2_size * sizeof(uint32_t)) !=
550 s->l2_size * sizeof(uint32_t))
551 return 0;
552
553 s->l2_cache_offsets[min_index] = l2_offset;
554 s->l2_cache_counts[min_index] = 1;
555 found:
556 l2_index = ((offset >> 9) / s->cluster_sectors) % s->l2_size;
557 cluster_offset = le32_to_cpu(l2_table[l2_index]);
558
559 if (!cluster_offset) {
560 if (!allocate)
561 return 0;
562 // Avoid the L2 tables update for the images that have snapshots.
563 if (!s->is_parent) {
564 cluster_offset = bdrv_getlength(s->hd);
565 bdrv_truncate(s->hd, cluster_offset + (s->cluster_sectors << 9));
566
567 cluster_offset >>= 9;
568 tmp = cpu_to_le32(cluster_offset);
569 l2_table[l2_index] = tmp;
570 // Save the active image state
571 activeBDRV.cluster_offset = cluster_offset;
572 activeBDRV.hd = bs;
573 }
574 /* First of all we write grain itself, to avoid race condition
575 * that may to corrupt the image.
576 * This problem may occur because of insufficient space on host disk
577 * or inappropriate VM shutdown.
578 */
579 if (get_whole_cluster(bs, cluster_offset, offset, allocate) == -1)
580 return 0;
581
582 if (m_data) {
583 m_data->offset = tmp;
584 m_data->l1_index = l1_index;
585 m_data->l2_index = l2_index;
586 m_data->l2_offset = l2_offset;
587 m_data->valid = 1;
588 }
589 }
590 cluster_offset <<= 9;
591 return cluster_offset;
592 }
593
594 static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num,
595 int nb_sectors, int *pnum)
596 {
597 BDRVVmdkState *s = bs->opaque;
598 int index_in_cluster, n;
599 uint64_t cluster_offset;
600
601 cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0);
602 index_in_cluster = sector_num % s->cluster_sectors;
603 n = s->cluster_sectors - index_in_cluster;
604 if (n > nb_sectors)
605 n = nb_sectors;
606 *pnum = n;
607 return (cluster_offset != 0);
608 }
609
610 static int vmdk_read(BlockDriverState *bs, int64_t sector_num,
611 uint8_t *buf, int nb_sectors)
612 {
613 BDRVVmdkState *s = bs->opaque;
614 int index_in_cluster, n, ret;
615 uint64_t cluster_offset;
616
617 while (nb_sectors > 0) {
618 cluster_offset = get_cluster_offset(bs, NULL, sector_num << 9, 0);
619 index_in_cluster = sector_num % s->cluster_sectors;
620 n = s->cluster_sectors - index_in_cluster;
621 if (n > nb_sectors)
622 n = nb_sectors;
623 if (!cluster_offset) {
624 // try to read from parent image, if exist
625 if (bs->backing_hd) {
626 if (!vmdk_is_cid_valid(bs))
627 return -1;
628 ret = bdrv_read(bs->backing_hd, sector_num, buf, n);
629 if (ret < 0)
630 return -1;
631 } else {
632 memset(buf, 0, 512 * n);
633 }
634 } else {
635 if(bdrv_pread(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
636 return -1;
637 }
638 nb_sectors -= n;
639 sector_num += n;
640 buf += n * 512;
641 }
642 return 0;
643 }
644
645 static int vmdk_write(BlockDriverState *bs, int64_t sector_num,
646 const uint8_t *buf, int nb_sectors)
647 {
648 BDRVVmdkState *s = bs->opaque;
649 VmdkMetaData m_data;
650 int index_in_cluster, n;
651 uint64_t cluster_offset;
652 static int cid_update = 0;
653
654 if (sector_num > bs->total_sectors) {
655 fprintf(stderr,
656 "(VMDK) Wrong offset: sector_num=0x%" PRIx64
657 " total_sectors=0x%" PRIx64 "\n",
658 sector_num, bs->total_sectors);
659 return -1;
660 }
661
662 while (nb_sectors > 0) {
663 index_in_cluster = sector_num & (s->cluster_sectors - 1);
664 n = s->cluster_sectors - index_in_cluster;
665 if (n > nb_sectors)
666 n = nb_sectors;
667 cluster_offset = get_cluster_offset(bs, &m_data, sector_num << 9, 1);
668 if (!cluster_offset)
669 return -1;
670
671 if (bdrv_pwrite(s->hd, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512)
672 return -1;
673 if (m_data.valid) {
674 /* update L2 tables */
675 if (vmdk_L2update(bs, &m_data) == -1)
676 return -1;
677 }
678 nb_sectors -= n;
679 sector_num += n;
680 buf += n * 512;
681
682 // update CID on the first write every time the virtual disk is opened
683 if (!cid_update) {
684 vmdk_write_cid(bs, time(NULL));
685 cid_update++;
686 }
687 }
688 return 0;
689 }
690
691 static int vmdk_create(const char *filename, QEMUOptionParameter *options)
692 {
693 int fd, i;
694 VMDK4Header header;
695 uint32_t tmp, magic, grains, gd_size, gt_size, gt_count;
696 static const char desc_template[] =
697 "# Disk DescriptorFile\n"
698 "version=1\n"
699 "CID=%x\n"
700 "parentCID=ffffffff\n"
701 "createType=\"monolithicSparse\"\n"
702 "\n"
703 "# Extent description\n"
704 "RW %" PRId64 " SPARSE \"%s\"\n"
705 "\n"
706 "# The Disk Data Base \n"
707 "#DDB\n"
708 "\n"
709 "ddb.virtualHWVersion = \"%d\"\n"
710 "ddb.geometry.cylinders = \"%" PRId64 "\"\n"
711 "ddb.geometry.heads = \"16\"\n"
712 "ddb.geometry.sectors = \"63\"\n"
713 "ddb.adapterType = \"ide\"\n";
714 char desc[1024];
715 const char *real_filename, *temp_str;
716 int64_t total_size = 0;
717 const char *backing_file = NULL;
718 int flags = 0;
719
720 // Read out options
721 while (options && options->name) {
722 if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
723 total_size = options->value.n / 512;
724 } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
725 backing_file = options->value.s;
726 } else if (!strcmp(options->name, BLOCK_OPT_COMPAT6)) {
727 flags |= options->value.n ? BLOCK_FLAG_COMPAT6: 0;
728 }
729 options++;
730 }
731
732 /* XXX: add support for backing file */
733 if (backing_file) {
734 return vmdk_snapshot_create(filename, backing_file);
735 }
736
737 fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE,
738 0644);
739 if (fd < 0)
740 return -1;
741 magic = cpu_to_be32(VMDK4_MAGIC);
742 memset(&header, 0, sizeof(header));
743 header.version = cpu_to_le32(1);
744 header.flags = cpu_to_le32(3); /* ?? */
745 header.capacity = cpu_to_le64(total_size);
746 header.granularity = cpu_to_le64(128);
747 header.num_gtes_per_gte = cpu_to_le32(512);
748
749 grains = (total_size + header.granularity - 1) / header.granularity;
750 gt_size = ((header.num_gtes_per_gte * sizeof(uint32_t)) + 511) >> 9;
751 gt_count = (grains + header.num_gtes_per_gte - 1) / header.num_gtes_per_gte;
752 gd_size = (gt_count * sizeof(uint32_t) + 511) >> 9;
753
754 header.desc_offset = 1;
755 header.desc_size = 20;
756 header.rgd_offset = header.desc_offset + header.desc_size;
757 header.gd_offset = header.rgd_offset + gd_size + (gt_size * gt_count);
758 header.grain_offset =
759 ((header.gd_offset + gd_size + (gt_size * gt_count) +
760 header.granularity - 1) / header.granularity) *
761 header.granularity;
762
763 header.desc_offset = cpu_to_le64(header.desc_offset);
764 header.desc_size = cpu_to_le64(header.desc_size);
765 header.rgd_offset = cpu_to_le64(header.rgd_offset);
766 header.gd_offset = cpu_to_le64(header.gd_offset);
767 header.grain_offset = cpu_to_le64(header.grain_offset);
768
769 header.check_bytes[0] = 0xa;
770 header.check_bytes[1] = 0x20;
771 header.check_bytes[2] = 0xd;
772 header.check_bytes[3] = 0xa;
773
774 /* write all the data */
775 write(fd, &magic, sizeof(magic));
776 write(fd, &header, sizeof(header));
777
778 ftruncate(fd, header.grain_offset << 9);
779
780 /* write grain directory */
781 lseek(fd, le64_to_cpu(header.rgd_offset) << 9, SEEK_SET);
782 for (i = 0, tmp = header.rgd_offset + gd_size;
783 i < gt_count; i++, tmp += gt_size)
784 write(fd, &tmp, sizeof(tmp));
785
786 /* write backup grain directory */
787 lseek(fd, le64_to_cpu(header.gd_offset) << 9, SEEK_SET);
788 for (i = 0, tmp = header.gd_offset + gd_size;
789 i < gt_count; i++, tmp += gt_size)
790 write(fd, &tmp, sizeof(tmp));
791
792 /* compose the descriptor */
793 real_filename = filename;
794 if ((temp_str = strrchr(real_filename, '\\')) != NULL)
795 real_filename = temp_str + 1;
796 if ((temp_str = strrchr(real_filename, '/')) != NULL)
797 real_filename = temp_str + 1;
798 if ((temp_str = strrchr(real_filename, ':')) != NULL)
799 real_filename = temp_str + 1;
800 snprintf(desc, sizeof(desc), desc_template, (unsigned int)time(NULL),
801 total_size, real_filename,
802 (flags & BLOCK_FLAG_COMPAT6 ? 6 : 4),
803 total_size / (int64_t)(63 * 16));
804
805 /* write the descriptor */
806 lseek(fd, le64_to_cpu(header.desc_offset) << 9, SEEK_SET);
807 write(fd, desc, strlen(desc));
808
809 close(fd);
810 return 0;
811 }
812
813 static void vmdk_close(BlockDriverState *bs)
814 {
815 BDRVVmdkState *s = bs->opaque;
816
817 qemu_free(s->l1_table);
818 qemu_free(s->l2_cache);
819 // try to close parent image, if exist
820 vmdk_parent_close(s->hd);
821 bdrv_delete(s->hd);
822 }
823
824 static void vmdk_flush(BlockDriverState *bs)
825 {
826 BDRVVmdkState *s = bs->opaque;
827 bdrv_flush(s->hd);
828 }
829
830
831 static QEMUOptionParameter vmdk_create_options[] = {
832 {
833 .name = BLOCK_OPT_SIZE,
834 .type = OPT_SIZE,
835 .help = "Virtual disk size"
836 },
837 {
838 .name = BLOCK_OPT_BACKING_FILE,
839 .type = OPT_STRING,
840 .help = "File name of a base image"
841 },
842 {
843 .name = BLOCK_OPT_COMPAT6,
844 .type = OPT_FLAG,
845 .help = "VMDK version 6 image"
846 },
847 { NULL }
848 };
849
850 static BlockDriver bdrv_vmdk = {
851 .format_name = "vmdk",
852 .instance_size = sizeof(BDRVVmdkState),
853 .bdrv_probe = vmdk_probe,
854 .bdrv_open = vmdk_open,
855 .bdrv_read = vmdk_read,
856 .bdrv_write = vmdk_write,
857 .bdrv_close = vmdk_close,
858 .bdrv_create = vmdk_create,
859 .bdrv_flush = vmdk_flush,
860 .bdrv_is_allocated = vmdk_is_allocated,
861
862 .create_options = vmdk_create_options,
863 };
864
865 static void bdrv_vmdk_init(void)
866 {
867 bdrv_register(&bdrv_vmdk);
868 }
869
870 block_init(bdrv_vmdk_init);