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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 VmdkExtent { | |
64 | BlockDriverState *file; | |
65 | bool flat; | |
66 | int64_t sectors; | |
67 | int64_t end_sector; | |
68 | int64_t l1_table_offset; | |
69 | int64_t l1_backup_table_offset; | |
70 | uint32_t *l1_table; | |
71 | uint32_t *l1_backup_table; | |
72 | unsigned int l1_size; | |
73 | uint32_t l1_entry_sectors; | |
74 | ||
75 | unsigned int l2_size; | |
76 | uint32_t *l2_cache; | |
77 | uint32_t l2_cache_offsets[L2_CACHE_SIZE]; | |
78 | uint32_t l2_cache_counts[L2_CACHE_SIZE]; | |
79 | ||
80 | unsigned int cluster_sectors; | |
81 | } VmdkExtent; | |
82 | ||
83 | typedef struct BDRVVmdkState { | |
84 | uint32_t parent_cid; | |
85 | int num_extents; | |
86 | /* Extent array with num_extents entries, ascend ordered by address */ | |
87 | VmdkExtent *extents; | |
88 | } BDRVVmdkState; | |
89 | ||
90 | typedef struct VmdkMetaData { | |
91 | uint32_t offset; | |
92 | unsigned int l1_index; | |
93 | unsigned int l2_index; | |
94 | unsigned int l2_offset; | |
95 | int valid; | |
96 | } VmdkMetaData; | |
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 void vmdk_free_extents(BlockDriverState *bs) | |
119 | { | |
120 | int i; | |
121 | BDRVVmdkState *s = bs->opaque; | |
122 | ||
123 | for (i = 0; i < s->num_extents; i++) { | |
124 | qemu_free(s->extents[i].l1_table); | |
125 | qemu_free(s->extents[i].l2_cache); | |
126 | qemu_free(s->extents[i].l1_backup_table); | |
127 | } | |
128 | qemu_free(s->extents); | |
129 | } | |
130 | ||
131 | static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent) | |
132 | { | |
133 | char desc[DESC_SIZE]; | |
134 | uint32_t cid; | |
135 | const char *p_name, *cid_str; | |
136 | size_t cid_str_size; | |
137 | ||
138 | /* the descriptor offset = 0x200 */ | |
139 | if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE) | |
140 | return 0; | |
141 | ||
142 | if (parent) { | |
143 | cid_str = "parentCID"; | |
144 | cid_str_size = sizeof("parentCID"); | |
145 | } else { | |
146 | cid_str = "CID"; | |
147 | cid_str_size = sizeof("CID"); | |
148 | } | |
149 | ||
150 | if ((p_name = strstr(desc,cid_str)) != NULL) { | |
151 | p_name += cid_str_size; | |
152 | sscanf(p_name,"%x",&cid); | |
153 | } | |
154 | ||
155 | return cid; | |
156 | } | |
157 | ||
158 | static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid) | |
159 | { | |
160 | char desc[DESC_SIZE], tmp_desc[DESC_SIZE]; | |
161 | char *p_name, *tmp_str; | |
162 | ||
163 | /* the descriptor offset = 0x200 */ | |
164 | if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE) | |
165 | return -1; | |
166 | ||
167 | tmp_str = strstr(desc,"parentCID"); | |
168 | pstrcpy(tmp_desc, sizeof(tmp_desc), tmp_str); | |
169 | if ((p_name = strstr(desc,"CID")) != NULL) { | |
170 | p_name += sizeof("CID"); | |
171 | snprintf(p_name, sizeof(desc) - (p_name - desc), "%x\n", cid); | |
172 | pstrcat(desc, sizeof(desc), tmp_desc); | |
173 | } | |
174 | ||
175 | if (bdrv_pwrite_sync(bs->file, 0x200, desc, DESC_SIZE) < 0) | |
176 | return -1; | |
177 | return 0; | |
178 | } | |
179 | ||
180 | static int vmdk_is_cid_valid(BlockDriverState *bs) | |
181 | { | |
182 | #ifdef CHECK_CID | |
183 | BDRVVmdkState *s = bs->opaque; | |
184 | BlockDriverState *p_bs = bs->backing_hd; | |
185 | uint32_t cur_pcid; | |
186 | ||
187 | if (p_bs) { | |
188 | cur_pcid = vmdk_read_cid(p_bs,0); | |
189 | if (s->parent_cid != cur_pcid) | |
190 | // CID not valid | |
191 | return 0; | |
192 | } | |
193 | #endif | |
194 | // CID valid | |
195 | return 1; | |
196 | } | |
197 | ||
198 | static int vmdk_snapshot_create(const char *filename, const char *backing_file) | |
199 | { | |
200 | int snp_fd, p_fd; | |
201 | int ret; | |
202 | uint32_t p_cid; | |
203 | char *p_name, *gd_buf, *rgd_buf; | |
204 | const char *real_filename, *temp_str; | |
205 | VMDK4Header header; | |
206 | uint32_t gde_entries, gd_size; | |
207 | int64_t gd_offset, rgd_offset, capacity, gt_size; | |
208 | char p_desc[DESC_SIZE], s_desc[DESC_SIZE], hdr[HEADER_SIZE]; | |
209 | static const char desc_template[] = | |
210 | "# Disk DescriptorFile\n" | |
211 | "version=1\n" | |
212 | "CID=%x\n" | |
213 | "parentCID=%x\n" | |
214 | "createType=\"monolithicSparse\"\n" | |
215 | "parentFileNameHint=\"%s\"\n" | |
216 | "\n" | |
217 | "# Extent description\n" | |
218 | "RW %u SPARSE \"%s\"\n" | |
219 | "\n" | |
220 | "# The Disk Data Base \n" | |
221 | "#DDB\n" | |
222 | "\n"; | |
223 | ||
224 | snp_fd = open(filename, O_RDWR | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, 0644); | |
225 | if (snp_fd < 0) | |
226 | return -errno; | |
227 | p_fd = open(backing_file, O_RDONLY | O_BINARY | O_LARGEFILE); | |
228 | if (p_fd < 0) { | |
229 | close(snp_fd); | |
230 | return -errno; | |
231 | } | |
232 | ||
233 | /* read the header */ | |
234 | if (lseek(p_fd, 0x0, SEEK_SET) == -1) { | |
235 | ret = -errno; | |
236 | goto fail; | |
237 | } | |
238 | if (read(p_fd, hdr, HEADER_SIZE) != HEADER_SIZE) { | |
239 | ret = -errno; | |
240 | goto fail; | |
241 | } | |
242 | ||
243 | /* write the header */ | |
244 | if (lseek(snp_fd, 0x0, SEEK_SET) == -1) { | |
245 | ret = -errno; | |
246 | goto fail; | |
247 | } | |
248 | if (write(snp_fd, hdr, HEADER_SIZE) == -1) { | |
249 | ret = -errno; | |
250 | goto fail; | |
251 | } | |
252 | ||
253 | memset(&header, 0, sizeof(header)); | |
254 | memcpy(&header,&hdr[4], sizeof(header)); // skip the VMDK4_MAGIC | |
255 | ||
256 | if (ftruncate(snp_fd, header.grain_offset << 9)) { | |
257 | ret = -errno; | |
258 | goto fail; | |
259 | } | |
260 | /* the descriptor offset = 0x200 */ | |
261 | if (lseek(p_fd, 0x200, SEEK_SET) == -1) { | |
262 | ret = -errno; | |
263 | goto fail; | |
264 | } | |
265 | if (read(p_fd, p_desc, DESC_SIZE) != DESC_SIZE) { | |
266 | ret = -errno; | |
267 | goto fail; | |
268 | } | |
269 | ||
270 | if ((p_name = strstr(p_desc,"CID")) != NULL) { | |
271 | p_name += sizeof("CID"); | |
272 | sscanf(p_name,"%x",&p_cid); | |
273 | } | |
274 | ||
275 | real_filename = filename; | |
276 | if ((temp_str = strrchr(real_filename, '\\')) != NULL) | |
277 | real_filename = temp_str + 1; | |
278 | if ((temp_str = strrchr(real_filename, '/')) != NULL) | |
279 | real_filename = temp_str + 1; | |
280 | if ((temp_str = strrchr(real_filename, ':')) != NULL) | |
281 | real_filename = temp_str + 1; | |
282 | ||
283 | snprintf(s_desc, sizeof(s_desc), desc_template, p_cid, p_cid, backing_file, | |
284 | (uint32_t)header.capacity, real_filename); | |
285 | ||
286 | /* write the descriptor */ | |
287 | if (lseek(snp_fd, 0x200, SEEK_SET) == -1) { | |
288 | ret = -errno; | |
289 | goto fail; | |
290 | } | |
291 | if (write(snp_fd, s_desc, strlen(s_desc)) == -1) { | |
292 | ret = -errno; | |
293 | goto fail; | |
294 | } | |
295 | ||
296 | gd_offset = header.gd_offset * SECTOR_SIZE; // offset of GD table | |
297 | rgd_offset = header.rgd_offset * SECTOR_SIZE; // offset of RGD table | |
298 | capacity = header.capacity * SECTOR_SIZE; // Extent size | |
299 | /* | |
300 | * Each GDE span 32M disk, means: | |
301 | * 512 GTE per GT, each GTE points to grain | |
302 | */ | |
303 | gt_size = (int64_t)header.num_gtes_per_gte * header.granularity * SECTOR_SIZE; | |
304 | if (!gt_size) { | |
305 | ret = -EINVAL; | |
306 | goto fail; | |
307 | } | |
308 | gde_entries = (uint32_t)(capacity / gt_size); // number of gde/rgde | |
309 | gd_size = gde_entries * sizeof(uint32_t); | |
310 | ||
311 | /* write RGD */ | |
312 | rgd_buf = qemu_malloc(gd_size); | |
313 | if (lseek(p_fd, rgd_offset, SEEK_SET) == -1) { | |
314 | ret = -errno; | |
315 | goto fail_rgd; | |
316 | } | |
317 | if (read(p_fd, rgd_buf, gd_size) != gd_size) { | |
318 | ret = -errno; | |
319 | goto fail_rgd; | |
320 | } | |
321 | if (lseek(snp_fd, rgd_offset, SEEK_SET) == -1) { | |
322 | ret = -errno; | |
323 | goto fail_rgd; | |
324 | } | |
325 | if (write(snp_fd, rgd_buf, gd_size) == -1) { | |
326 | ret = -errno; | |
327 | goto fail_rgd; | |
328 | } | |
329 | ||
330 | /* write GD */ | |
331 | gd_buf = qemu_malloc(gd_size); | |
332 | if (lseek(p_fd, gd_offset, SEEK_SET) == -1) { | |
333 | ret = -errno; | |
334 | goto fail_gd; | |
335 | } | |
336 | if (read(p_fd, gd_buf, gd_size) != gd_size) { | |
337 | ret = -errno; | |
338 | goto fail_gd; | |
339 | } | |
340 | if (lseek(snp_fd, gd_offset, SEEK_SET) == -1) { | |
341 | ret = -errno; | |
342 | goto fail_gd; | |
343 | } | |
344 | if (write(snp_fd, gd_buf, gd_size) == -1) { | |
345 | ret = -errno; | |
346 | goto fail_gd; | |
347 | } | |
348 | ret = 0; | |
349 | ||
350 | fail_gd: | |
351 | qemu_free(gd_buf); | |
352 | fail_rgd: | |
353 | qemu_free(rgd_buf); | |
354 | fail: | |
355 | close(p_fd); | |
356 | close(snp_fd); | |
357 | return ret; | |
358 | } | |
359 | ||
360 | static int vmdk_parent_open(BlockDriverState *bs) | |
361 | { | |
362 | char *p_name; | |
363 | char desc[DESC_SIZE]; | |
364 | ||
365 | /* the descriptor offset = 0x200 */ | |
366 | if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE) | |
367 | return -1; | |
368 | ||
369 | if ((p_name = strstr(desc,"parentFileNameHint")) != NULL) { | |
370 | char *end_name; | |
371 | ||
372 | p_name += sizeof("parentFileNameHint") + 1; | |
373 | if ((end_name = strchr(p_name,'\"')) == NULL) | |
374 | return -1; | |
375 | if ((end_name - p_name) > sizeof (bs->backing_file) - 1) | |
376 | return -1; | |
377 | ||
378 | pstrcpy(bs->backing_file, end_name - p_name + 1, p_name); | |
379 | } | |
380 | ||
381 | return 0; | |
382 | } | |
383 | ||
384 | /* Create and append extent to the extent array. Return the added VmdkExtent | |
385 | * address. return NULL if allocation failed. */ | |
386 | static VmdkExtent *vmdk_add_extent(BlockDriverState *bs, | |
387 | BlockDriverState *file, bool flat, int64_t sectors, | |
388 | int64_t l1_offset, int64_t l1_backup_offset, | |
389 | uint32_t l1_size, | |
390 | int l2_size, unsigned int cluster_sectors) | |
391 | { | |
392 | VmdkExtent *extent; | |
393 | BDRVVmdkState *s = bs->opaque; | |
394 | ||
395 | s->extents = qemu_realloc(s->extents, | |
396 | (s->num_extents + 1) * sizeof(VmdkExtent)); | |
397 | extent = &s->extents[s->num_extents]; | |
398 | s->num_extents++; | |
399 | ||
400 | memset(extent, 0, sizeof(VmdkExtent)); | |
401 | extent->file = file; | |
402 | extent->flat = flat; | |
403 | extent->sectors = sectors; | |
404 | extent->l1_table_offset = l1_offset; | |
405 | extent->l1_backup_table_offset = l1_backup_offset; | |
406 | extent->l1_size = l1_size; | |
407 | extent->l1_entry_sectors = l2_size * cluster_sectors; | |
408 | extent->l2_size = l2_size; | |
409 | extent->cluster_sectors = cluster_sectors; | |
410 | ||
411 | if (s->num_extents > 1) { | |
412 | extent->end_sector = (*(extent - 1)).end_sector + extent->sectors; | |
413 | } else { | |
414 | extent->end_sector = extent->sectors; | |
415 | } | |
416 | bs->total_sectors = extent->end_sector; | |
417 | return extent; | |
418 | } | |
419 | ||
420 | ||
421 | static int vmdk_open(BlockDriverState *bs, int flags) | |
422 | { | |
423 | BDRVVmdkState *s = bs->opaque; | |
424 | uint32_t magic; | |
425 | int i; | |
426 | uint32_t l1_size, l1_entry_sectors; | |
427 | VmdkExtent *extent = NULL; | |
428 | ||
429 | if (bdrv_pread(bs->file, 0, &magic, sizeof(magic)) != sizeof(magic)) | |
430 | goto fail; | |
431 | ||
432 | magic = be32_to_cpu(magic); | |
433 | if (magic == VMDK3_MAGIC) { | |
434 | VMDK3Header header; | |
435 | if (bdrv_pread(bs->file, sizeof(magic), &header, sizeof(header)) | |
436 | != sizeof(header)) { | |
437 | goto fail; | |
438 | } | |
439 | extent = vmdk_add_extent(bs, bs->file, false, | |
440 | le32_to_cpu(header.disk_sectors), | |
441 | le32_to_cpu(header.l1dir_offset) << 9, 0, | |
442 | 1 << 6, 1 << 9, le32_to_cpu(header.granularity)); | |
443 | } else if (magic == VMDK4_MAGIC) { | |
444 | VMDK4Header header; | |
445 | if (bdrv_pread(bs->file, sizeof(magic), &header, sizeof(header)) | |
446 | != sizeof(header)) { | |
447 | goto fail; | |
448 | } | |
449 | l1_entry_sectors = le32_to_cpu(header.num_gtes_per_gte) | |
450 | * le64_to_cpu(header.granularity); | |
451 | l1_size = (le64_to_cpu(header.capacity) + l1_entry_sectors - 1) | |
452 | / l1_entry_sectors; | |
453 | extent = vmdk_add_extent(bs, bs->file, false, | |
454 | le64_to_cpu(header.capacity), | |
455 | le64_to_cpu(header.gd_offset) << 9, | |
456 | le64_to_cpu(header.rgd_offset) << 9, | |
457 | l1_size, | |
458 | le32_to_cpu(header.num_gtes_per_gte), | |
459 | le64_to_cpu(header.granularity)); | |
460 | if (extent->l1_entry_sectors <= 0) { | |
461 | goto fail; | |
462 | } | |
463 | // try to open parent images, if exist | |
464 | if (vmdk_parent_open(bs) != 0) | |
465 | goto fail; | |
466 | // write the CID once after the image creation | |
467 | s->parent_cid = vmdk_read_cid(bs,1); | |
468 | } else { | |
469 | goto fail; | |
470 | } | |
471 | ||
472 | /* read the L1 table */ | |
473 | l1_size = extent->l1_size * sizeof(uint32_t); | |
474 | extent->l1_table = qemu_malloc(l1_size); | |
475 | if (bdrv_pread(bs->file, | |
476 | extent->l1_table_offset, | |
477 | extent->l1_table, | |
478 | l1_size) | |
479 | != l1_size) { | |
480 | goto fail; | |
481 | } | |
482 | for (i = 0; i < extent->l1_size; i++) { | |
483 | le32_to_cpus(&extent->l1_table[i]); | |
484 | } | |
485 | ||
486 | if (extent->l1_backup_table_offset) { | |
487 | extent->l1_backup_table = qemu_malloc(l1_size); | |
488 | if (bdrv_pread(bs->file, | |
489 | extent->l1_backup_table_offset, | |
490 | extent->l1_backup_table, | |
491 | l1_size) | |
492 | != l1_size) { | |
493 | goto fail; | |
494 | } | |
495 | for (i = 0; i < extent->l1_size; i++) { | |
496 | le32_to_cpus(&extent->l1_backup_table[i]); | |
497 | } | |
498 | } | |
499 | ||
500 | extent->l2_cache = | |
501 | qemu_malloc(extent->l2_size * L2_CACHE_SIZE * sizeof(uint32_t)); | |
502 | return 0; | |
503 | fail: | |
504 | vmdk_free_extents(bs); | |
505 | return -1; | |
506 | } | |
507 | ||
508 | static int get_whole_cluster(BlockDriverState *bs, | |
509 | VmdkExtent *extent, | |
510 | uint64_t cluster_offset, | |
511 | uint64_t offset, | |
512 | bool allocate) | |
513 | { | |
514 | /* 128 sectors * 512 bytes each = grain size 64KB */ | |
515 | uint8_t whole_grain[extent->cluster_sectors * 512]; | |
516 | ||
517 | // we will be here if it's first write on non-exist grain(cluster). | |
518 | // try to read from parent image, if exist | |
519 | if (bs->backing_hd) { | |
520 | int ret; | |
521 | ||
522 | if (!vmdk_is_cid_valid(bs)) | |
523 | return -1; | |
524 | ||
525 | ret = bdrv_read(bs->backing_hd, offset >> 9, whole_grain, | |
526 | extent->cluster_sectors); | |
527 | if (ret < 0) { | |
528 | return -1; | |
529 | } | |
530 | ||
531 | //Write grain only into the active image | |
532 | ret = bdrv_write(extent->file, cluster_offset, whole_grain, | |
533 | extent->cluster_sectors); | |
534 | if (ret < 0) { | |
535 | return -1; | |
536 | } | |
537 | } | |
538 | return 0; | |
539 | } | |
540 | ||
541 | static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data) | |
542 | { | |
543 | /* update L2 table */ | |
544 | if (bdrv_pwrite_sync( | |
545 | extent->file, | |
546 | ((int64_t)m_data->l2_offset * 512) | |
547 | + (m_data->l2_index * sizeof(m_data->offset)), | |
548 | &(m_data->offset), | |
549 | sizeof(m_data->offset) | |
550 | ) < 0) { | |
551 | return -1; | |
552 | } | |
553 | /* update backup L2 table */ | |
554 | if (extent->l1_backup_table_offset != 0) { | |
555 | m_data->l2_offset = extent->l1_backup_table[m_data->l1_index]; | |
556 | if (bdrv_pwrite_sync( | |
557 | extent->file, | |
558 | ((int64_t)m_data->l2_offset * 512) | |
559 | + (m_data->l2_index * sizeof(m_data->offset)), | |
560 | &(m_data->offset), sizeof(m_data->offset) | |
561 | ) < 0) { | |
562 | return -1; | |
563 | } | |
564 | } | |
565 | ||
566 | return 0; | |
567 | } | |
568 | ||
569 | static uint64_t get_cluster_offset(BlockDriverState *bs, | |
570 | VmdkExtent *extent, | |
571 | VmdkMetaData *m_data, | |
572 | uint64_t offset, int allocate) | |
573 | { | |
574 | unsigned int l1_index, l2_offset, l2_index; | |
575 | int min_index, i, j; | |
576 | uint32_t min_count, *l2_table, tmp = 0; | |
577 | uint64_t cluster_offset; | |
578 | ||
579 | if (m_data) | |
580 | m_data->valid = 0; | |
581 | ||
582 | l1_index = (offset >> 9) / extent->l1_entry_sectors; | |
583 | if (l1_index >= extent->l1_size) { | |
584 | return 0; | |
585 | } | |
586 | l2_offset = extent->l1_table[l1_index]; | |
587 | if (!l2_offset) { | |
588 | return 0; | |
589 | } | |
590 | for(i = 0; i < L2_CACHE_SIZE; i++) { | |
591 | if (l2_offset == extent->l2_cache_offsets[i]) { | |
592 | /* increment the hit count */ | |
593 | if (++extent->l2_cache_counts[i] == 0xffffffff) { | |
594 | for(j = 0; j < L2_CACHE_SIZE; j++) { | |
595 | extent->l2_cache_counts[j] >>= 1; | |
596 | } | |
597 | } | |
598 | l2_table = extent->l2_cache + (i * extent->l2_size); | |
599 | goto found; | |
600 | } | |
601 | } | |
602 | /* not found: load a new entry in the least used one */ | |
603 | min_index = 0; | |
604 | min_count = 0xffffffff; | |
605 | for(i = 0; i < L2_CACHE_SIZE; i++) { | |
606 | if (extent->l2_cache_counts[i] < min_count) { | |
607 | min_count = extent->l2_cache_counts[i]; | |
608 | min_index = i; | |
609 | } | |
610 | } | |
611 | l2_table = extent->l2_cache + (min_index * extent->l2_size); | |
612 | if (bdrv_pread( | |
613 | extent->file, | |
614 | (int64_t)l2_offset * 512, | |
615 | l2_table, | |
616 | extent->l2_size * sizeof(uint32_t) | |
617 | ) != extent->l2_size * sizeof(uint32_t)) { | |
618 | return 0; | |
619 | } | |
620 | ||
621 | extent->l2_cache_offsets[min_index] = l2_offset; | |
622 | extent->l2_cache_counts[min_index] = 1; | |
623 | found: | |
624 | l2_index = ((offset >> 9) / extent->cluster_sectors) % extent->l2_size; | |
625 | cluster_offset = le32_to_cpu(l2_table[l2_index]); | |
626 | ||
627 | if (!cluster_offset) { | |
628 | if (!allocate) | |
629 | return 0; | |
630 | ||
631 | // Avoid the L2 tables update for the images that have snapshots. | |
632 | cluster_offset = bdrv_getlength(extent->file); | |
633 | bdrv_truncate( | |
634 | extent->file, | |
635 | cluster_offset + (extent->cluster_sectors << 9) | |
636 | ); | |
637 | ||
638 | cluster_offset >>= 9; | |
639 | tmp = cpu_to_le32(cluster_offset); | |
640 | l2_table[l2_index] = tmp; | |
641 | ||
642 | /* First of all we write grain itself, to avoid race condition | |
643 | * that may to corrupt the image. | |
644 | * This problem may occur because of insufficient space on host disk | |
645 | * or inappropriate VM shutdown. | |
646 | */ | |
647 | if (get_whole_cluster( | |
648 | bs, extent, cluster_offset, offset, allocate) == -1) | |
649 | return 0; | |
650 | ||
651 | if (m_data) { | |
652 | m_data->offset = tmp; | |
653 | m_data->l1_index = l1_index; | |
654 | m_data->l2_index = l2_index; | |
655 | m_data->l2_offset = l2_offset; | |
656 | m_data->valid = 1; | |
657 | } | |
658 | } | |
659 | cluster_offset <<= 9; | |
660 | return cluster_offset; | |
661 | } | |
662 | ||
663 | static VmdkExtent *find_extent(BDRVVmdkState *s, | |
664 | int64_t sector_num, VmdkExtent *start_hint) | |
665 | { | |
666 | VmdkExtent *extent = start_hint; | |
667 | ||
668 | if (!extent) { | |
669 | extent = &s->extents[0]; | |
670 | } | |
671 | while (extent < &s->extents[s->num_extents]) { | |
672 | if (sector_num < extent->end_sector) { | |
673 | return extent; | |
674 | } | |
675 | extent++; | |
676 | } | |
677 | return NULL; | |
678 | } | |
679 | ||
680 | static int vmdk_is_allocated(BlockDriverState *bs, int64_t sector_num, | |
681 | int nb_sectors, int *pnum) | |
682 | { | |
683 | BDRVVmdkState *s = bs->opaque; | |
684 | ||
685 | int64_t index_in_cluster, n, ret; | |
686 | uint64_t offset; | |
687 | VmdkExtent *extent; | |
688 | ||
689 | extent = find_extent(s, sector_num, NULL); | |
690 | if (!extent) { | |
691 | return 0; | |
692 | } | |
693 | if (extent->flat) { | |
694 | n = extent->end_sector - sector_num; | |
695 | ret = 1; | |
696 | } else { | |
697 | offset = get_cluster_offset(bs, extent, NULL, sector_num * 512, 0); | |
698 | index_in_cluster = sector_num % extent->cluster_sectors; | |
699 | n = extent->cluster_sectors - index_in_cluster; | |
700 | ret = offset ? 1 : 0; | |
701 | } | |
702 | if (n > nb_sectors) | |
703 | n = nb_sectors; | |
704 | *pnum = n; | |
705 | return ret; | |
706 | } | |
707 | ||
708 | static int vmdk_read(BlockDriverState *bs, int64_t sector_num, | |
709 | uint8_t *buf, int nb_sectors) | |
710 | { | |
711 | BDRVVmdkState *s = bs->opaque; | |
712 | int ret; | |
713 | uint64_t n, index_in_cluster; | |
714 | VmdkExtent *extent = NULL; | |
715 | uint64_t cluster_offset; | |
716 | ||
717 | while (nb_sectors > 0) { | |
718 | extent = find_extent(s, sector_num, extent); | |
719 | if (!extent) { | |
720 | return -EIO; | |
721 | } | |
722 | cluster_offset = get_cluster_offset( | |
723 | bs, extent, NULL, sector_num << 9, 0); | |
724 | index_in_cluster = sector_num % extent->cluster_sectors; | |
725 | n = extent->cluster_sectors - index_in_cluster; | |
726 | if (n > nb_sectors) | |
727 | n = nb_sectors; | |
728 | if (!cluster_offset) { | |
729 | // try to read from parent image, if exist | |
730 | if (bs->backing_hd) { | |
731 | if (!vmdk_is_cid_valid(bs)) | |
732 | return -1; | |
733 | ret = bdrv_read(bs->backing_hd, sector_num, buf, n); | |
734 | if (ret < 0) | |
735 | return -1; | |
736 | } else { | |
737 | memset(buf, 0, 512 * n); | |
738 | } | |
739 | } else { | |
740 | if(bdrv_pread(bs->file, cluster_offset + index_in_cluster * 512, buf, n * 512) != n * 512) | |
741 | return -1; | |
742 | } | |
743 | nb_sectors -= n; | |
744 | sector_num += n; | |
745 | buf += n * 512; | |
746 | } | |
747 | return 0; | |
748 | } | |
749 | ||
750 | static int vmdk_write(BlockDriverState *bs, int64_t sector_num, | |
751 | const uint8_t *buf, int nb_sectors) | |
752 | { | |
753 | BDRVVmdkState *s = bs->opaque; | |
754 | VmdkExtent *extent = NULL; | |
755 | int n; | |
756 | int64_t index_in_cluster; | |
757 | uint64_t cluster_offset; | |
758 | static int cid_update = 0; | |
759 | VmdkMetaData m_data; | |
760 | ||
761 | if (sector_num > bs->total_sectors) { | |
762 | fprintf(stderr, | |
763 | "(VMDK) Wrong offset: sector_num=0x%" PRIx64 | |
764 | " total_sectors=0x%" PRIx64 "\n", | |
765 | sector_num, bs->total_sectors); | |
766 | return -1; | |
767 | } | |
768 | ||
769 | while (nb_sectors > 0) { | |
770 | extent = find_extent(s, sector_num, extent); | |
771 | if (!extent) { | |
772 | return -EIO; | |
773 | } | |
774 | cluster_offset = get_cluster_offset( | |
775 | bs, | |
776 | extent, | |
777 | &m_data, | |
778 | sector_num << 9, 1); | |
779 | if (!cluster_offset) { | |
780 | return -1; | |
781 | } | |
782 | index_in_cluster = sector_num % extent->cluster_sectors; | |
783 | n = extent->cluster_sectors - index_in_cluster; | |
784 | if (n > nb_sectors) { | |
785 | n = nb_sectors; | |
786 | } | |
787 | ||
788 | if (bdrv_pwrite(bs->file, | |
789 | cluster_offset + index_in_cluster * 512, | |
790 | buf, n * 512) | |
791 | != n * 512) { | |
792 | return -1; | |
793 | } | |
794 | if (m_data.valid) { | |
795 | /* update L2 tables */ | |
796 | if (vmdk_L2update(extent, &m_data) == -1) { | |
797 | return -1; | |
798 | } | |
799 | } | |
800 | nb_sectors -= n; | |
801 | sector_num += n; | |
802 | buf += n * 512; | |
803 | ||
804 | // update CID on the first write every time the virtual disk is opened | |
805 | if (!cid_update) { | |
806 | vmdk_write_cid(bs, time(NULL)); | |
807 | cid_update++; | |
808 | } | |
809 | } | |
810 | return 0; | |
811 | } | |
812 | ||
813 | static int vmdk_create(const char *filename, QEMUOptionParameter *options) | |
814 | { | |
815 | int fd, i; | |
816 | VMDK4Header header; | |
817 | uint32_t tmp, magic, grains, gd_size, gt_size, gt_count; | |
818 | static const char desc_template[] = | |
819 | "# Disk DescriptorFile\n" | |
820 | "version=1\n" | |
821 | "CID=%x\n" | |
822 | "parentCID=ffffffff\n" | |
823 | "createType=\"monolithicSparse\"\n" | |
824 | "\n" | |
825 | "# Extent description\n" | |
826 | "RW %" PRId64 " SPARSE \"%s\"\n" | |
827 | "\n" | |
828 | "# The Disk Data Base \n" | |
829 | "#DDB\n" | |
830 | "\n" | |
831 | "ddb.virtualHWVersion = \"%d\"\n" | |
832 | "ddb.geometry.cylinders = \"%" PRId64 "\"\n" | |
833 | "ddb.geometry.heads = \"16\"\n" | |
834 | "ddb.geometry.sectors = \"63\"\n" | |
835 | "ddb.adapterType = \"ide\"\n"; | |
836 | char desc[1024]; | |
837 | const char *real_filename, *temp_str; | |
838 | int64_t total_size = 0; | |
839 | const char *backing_file = NULL; | |
840 | int flags = 0; | |
841 | int ret; | |
842 | ||
843 | // Read out options | |
844 | while (options && options->name) { | |
845 | if (!strcmp(options->name, BLOCK_OPT_SIZE)) { | |
846 | total_size = options->value.n / 512; | |
847 | } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) { | |
848 | backing_file = options->value.s; | |
849 | } else if (!strcmp(options->name, BLOCK_OPT_COMPAT6)) { | |
850 | flags |= options->value.n ? BLOCK_FLAG_COMPAT6: 0; | |
851 | } | |
852 | options++; | |
853 | } | |
854 | ||
855 | /* XXX: add support for backing file */ | |
856 | if (backing_file) { | |
857 | return vmdk_snapshot_create(filename, backing_file); | |
858 | } | |
859 | ||
860 | fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, | |
861 | 0644); | |
862 | if (fd < 0) | |
863 | return -errno; | |
864 | magic = cpu_to_be32(VMDK4_MAGIC); | |
865 | memset(&header, 0, sizeof(header)); | |
866 | header.version = 1; | |
867 | header.flags = 3; /* ?? */ | |
868 | header.capacity = total_size; | |
869 | header.granularity = 128; | |
870 | header.num_gtes_per_gte = 512; | |
871 | ||
872 | grains = (total_size + header.granularity - 1) / header.granularity; | |
873 | gt_size = ((header.num_gtes_per_gte * sizeof(uint32_t)) + 511) >> 9; | |
874 | gt_count = (grains + header.num_gtes_per_gte - 1) / header.num_gtes_per_gte; | |
875 | gd_size = (gt_count * sizeof(uint32_t) + 511) >> 9; | |
876 | ||
877 | header.desc_offset = 1; | |
878 | header.desc_size = 20; | |
879 | header.rgd_offset = header.desc_offset + header.desc_size; | |
880 | header.gd_offset = header.rgd_offset + gd_size + (gt_size * gt_count); | |
881 | header.grain_offset = | |
882 | ((header.gd_offset + gd_size + (gt_size * gt_count) + | |
883 | header.granularity - 1) / header.granularity) * | |
884 | header.granularity; | |
885 | ||
886 | /* swap endianness for all header fields */ | |
887 | header.version = cpu_to_le32(header.version); | |
888 | header.flags = cpu_to_le32(header.flags); | |
889 | header.capacity = cpu_to_le64(header.capacity); | |
890 | header.granularity = cpu_to_le64(header.granularity); | |
891 | header.num_gtes_per_gte = cpu_to_le32(header.num_gtes_per_gte); | |
892 | header.desc_offset = cpu_to_le64(header.desc_offset); | |
893 | header.desc_size = cpu_to_le64(header.desc_size); | |
894 | header.rgd_offset = cpu_to_le64(header.rgd_offset); | |
895 | header.gd_offset = cpu_to_le64(header.gd_offset); | |
896 | header.grain_offset = cpu_to_le64(header.grain_offset); | |
897 | ||
898 | header.check_bytes[0] = 0xa; | |
899 | header.check_bytes[1] = 0x20; | |
900 | header.check_bytes[2] = 0xd; | |
901 | header.check_bytes[3] = 0xa; | |
902 | ||
903 | /* write all the data */ | |
904 | ret = qemu_write_full(fd, &magic, sizeof(magic)); | |
905 | if (ret != sizeof(magic)) { | |
906 | ret = -errno; | |
907 | goto exit; | |
908 | } | |
909 | ret = qemu_write_full(fd, &header, sizeof(header)); | |
910 | if (ret != sizeof(header)) { | |
911 | ret = -errno; | |
912 | goto exit; | |
913 | } | |
914 | ||
915 | ret = ftruncate(fd, le64_to_cpu(header.grain_offset) << 9); | |
916 | if (ret < 0) { | |
917 | ret = -errno; | |
918 | goto exit; | |
919 | } | |
920 | ||
921 | /* write grain directory */ | |
922 | lseek(fd, le64_to_cpu(header.rgd_offset) << 9, SEEK_SET); | |
923 | for (i = 0, tmp = le64_to_cpu(header.rgd_offset) + gd_size; | |
924 | i < gt_count; i++, tmp += gt_size) { | |
925 | ret = qemu_write_full(fd, &tmp, sizeof(tmp)); | |
926 | if (ret != sizeof(tmp)) { | |
927 | ret = -errno; | |
928 | goto exit; | |
929 | } | |
930 | } | |
931 | ||
932 | /* write backup grain directory */ | |
933 | lseek(fd, le64_to_cpu(header.gd_offset) << 9, SEEK_SET); | |
934 | for (i = 0, tmp = le64_to_cpu(header.gd_offset) + gd_size; | |
935 | i < gt_count; i++, tmp += gt_size) { | |
936 | ret = qemu_write_full(fd, &tmp, sizeof(tmp)); | |
937 | if (ret != sizeof(tmp)) { | |
938 | ret = -errno; | |
939 | goto exit; | |
940 | } | |
941 | } | |
942 | ||
943 | /* compose the descriptor */ | |
944 | real_filename = filename; | |
945 | if ((temp_str = strrchr(real_filename, '\\')) != NULL) | |
946 | real_filename = temp_str + 1; | |
947 | if ((temp_str = strrchr(real_filename, '/')) != NULL) | |
948 | real_filename = temp_str + 1; | |
949 | if ((temp_str = strrchr(real_filename, ':')) != NULL) | |
950 | real_filename = temp_str + 1; | |
951 | snprintf(desc, sizeof(desc), desc_template, (unsigned int)time(NULL), | |
952 | total_size, real_filename, | |
953 | (flags & BLOCK_FLAG_COMPAT6 ? 6 : 4), | |
954 | total_size / (int64_t)(63 * 16)); | |
955 | ||
956 | /* write the descriptor */ | |
957 | lseek(fd, le64_to_cpu(header.desc_offset) << 9, SEEK_SET); | |
958 | ret = qemu_write_full(fd, desc, strlen(desc)); | |
959 | if (ret != strlen(desc)) { | |
960 | ret = -errno; | |
961 | goto exit; | |
962 | } | |
963 | ||
964 | ret = 0; | |
965 | exit: | |
966 | close(fd); | |
967 | return ret; | |
968 | } | |
969 | ||
970 | static void vmdk_close(BlockDriverState *bs) | |
971 | { | |
972 | vmdk_free_extents(bs); | |
973 | } | |
974 | ||
975 | static int vmdk_flush(BlockDriverState *bs) | |
976 | { | |
977 | return bdrv_flush(bs->file); | |
978 | } | |
979 | ||
980 | ||
981 | static QEMUOptionParameter vmdk_create_options[] = { | |
982 | { | |
983 | .name = BLOCK_OPT_SIZE, | |
984 | .type = OPT_SIZE, | |
985 | .help = "Virtual disk size" | |
986 | }, | |
987 | { | |
988 | .name = BLOCK_OPT_BACKING_FILE, | |
989 | .type = OPT_STRING, | |
990 | .help = "File name of a base image" | |
991 | }, | |
992 | { | |
993 | .name = BLOCK_OPT_COMPAT6, | |
994 | .type = OPT_FLAG, | |
995 | .help = "VMDK version 6 image" | |
996 | }, | |
997 | { NULL } | |
998 | }; | |
999 | ||
1000 | static BlockDriver bdrv_vmdk = { | |
1001 | .format_name = "vmdk", | |
1002 | .instance_size = sizeof(BDRVVmdkState), | |
1003 | .bdrv_probe = vmdk_probe, | |
1004 | .bdrv_open = vmdk_open, | |
1005 | .bdrv_read = vmdk_read, | |
1006 | .bdrv_write = vmdk_write, | |
1007 | .bdrv_close = vmdk_close, | |
1008 | .bdrv_create = vmdk_create, | |
1009 | .bdrv_flush = vmdk_flush, | |
1010 | .bdrv_is_allocated = vmdk_is_allocated, | |
1011 | ||
1012 | .create_options = vmdk_create_options, | |
1013 | }; | |
1014 | ||
1015 | static void bdrv_vmdk_init(void) | |
1016 | { | |
1017 | bdrv_register(&bdrv_vmdk); | |
1018 | } | |
1019 | ||
1020 | block_init(bdrv_vmdk_init); |