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88ddffae VSO |
1 | /* |
2 | * Bitmaps for the QCOW version 2 format | |
3 | * | |
4 | * Copyright (c) 2014-2017 Vladimir Sementsov-Ogievskiy | |
5 | * | |
6 | * This file is derived from qcow2-snapshot.c, original copyright: | |
7 | * Copyright (c) 2004-2006 Fabrice Bellard | |
8 | * | |
9 | * Permission is hereby granted, free of charge, to any person obtaining a copy | |
10 | * of this software and associated documentation files (the "Software"), to deal | |
11 | * in the Software without restriction, including without limitation the rights | |
12 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
13 | * copies of the Software, and to permit persons to whom the Software is | |
14 | * furnished to do so, subject to the following conditions: | |
15 | * | |
16 | * The above copyright notice and this permission notice shall be included in | |
17 | * all copies or substantial portions of the Software. | |
18 | * | |
19 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
20 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
21 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
22 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
23 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
24 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
25 | * THE SOFTWARE. | |
26 | */ | |
27 | ||
28 | #include "qemu/osdep.h" | |
29 | #include "qapi/error.h" | |
5f72826e | 30 | #include "qemu/cutils.h" |
88ddffae VSO |
31 | |
32 | #include "block/block_int.h" | |
33 | #include "block/qcow2.h" | |
34 | ||
35 | /* NOTICE: BME here means Bitmaps Extension and used as a namespace for | |
36 | * _internal_ constants. Please do not use this _internal_ abbreviation for | |
37 | * other needs and/or outside of this file. */ | |
38 | ||
39 | /* Bitmap directory entry constraints */ | |
40 | #define BME_MAX_TABLE_SIZE 0x8000000 | |
41 | #define BME_MAX_PHYS_SIZE 0x20000000 /* restrict BdrvDirtyBitmap size in RAM */ | |
42 | #define BME_MAX_GRANULARITY_BITS 31 | |
43 | #define BME_MIN_GRANULARITY_BITS 9 | |
44 | #define BME_MAX_NAME_SIZE 1023 | |
45 | ||
5f72826e VSO |
46 | #if BME_MAX_TABLE_SIZE * 8ULL > INT_MAX |
47 | #error In the code bitmap table physical size assumed to fit into int | |
48 | #endif | |
49 | ||
88ddffae VSO |
50 | /* Bitmap directory entry flags */ |
51 | #define BME_RESERVED_FLAGS 0xfffffffcU | |
d1258dd0 VSO |
52 | #define BME_FLAG_IN_USE (1U << 0) |
53 | #define BME_FLAG_AUTO (1U << 1) | |
88ddffae VSO |
54 | |
55 | /* bits [1, 8] U [56, 63] are reserved */ | |
56 | #define BME_TABLE_ENTRY_RESERVED_MASK 0xff000000000001feULL | |
57 | #define BME_TABLE_ENTRY_OFFSET_MASK 0x00fffffffffffe00ULL | |
58 | #define BME_TABLE_ENTRY_FLAG_ALL_ONES (1ULL << 0) | |
59 | ||
60 | typedef struct QEMU_PACKED Qcow2BitmapDirEntry { | |
61 | /* header is 8 byte aligned */ | |
62 | uint64_t bitmap_table_offset; | |
63 | ||
64 | uint32_t bitmap_table_size; | |
65 | uint32_t flags; | |
66 | ||
67 | uint8_t type; | |
68 | uint8_t granularity_bits; | |
69 | uint16_t name_size; | |
70 | uint32_t extra_data_size; | |
71 | /* extra data follows */ | |
72 | /* name follows */ | |
73 | } Qcow2BitmapDirEntry; | |
74 | ||
75 | typedef struct Qcow2BitmapTable { | |
76 | uint64_t offset; | |
77 | uint32_t size; /* number of 64bit entries */ | |
78 | QSIMPLEQ_ENTRY(Qcow2BitmapTable) entry; | |
79 | } Qcow2BitmapTable; | |
5f72826e VSO |
80 | typedef QSIMPLEQ_HEAD(Qcow2BitmapTableList, Qcow2BitmapTable) |
81 | Qcow2BitmapTableList; | |
88ddffae VSO |
82 | |
83 | typedef struct Qcow2Bitmap { | |
84 | Qcow2BitmapTable table; | |
85 | uint32_t flags; | |
86 | uint8_t granularity_bits; | |
87 | char *name; | |
88 | ||
5f72826e VSO |
89 | BdrvDirtyBitmap *dirty_bitmap; |
90 | ||
88ddffae VSO |
91 | QSIMPLEQ_ENTRY(Qcow2Bitmap) entry; |
92 | } Qcow2Bitmap; | |
93 | typedef QSIMPLEQ_HEAD(Qcow2BitmapList, Qcow2Bitmap) Qcow2BitmapList; | |
94 | ||
95 | typedef enum BitmapType { | |
96 | BT_DIRTY_TRACKING_BITMAP = 1 | |
97 | } BitmapType; | |
98 | ||
d1258dd0 VSO |
99 | static inline bool can_write(BlockDriverState *bs) |
100 | { | |
101 | return !bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE); | |
102 | } | |
103 | ||
104 | static int update_header_sync(BlockDriverState *bs) | |
105 | { | |
106 | int ret; | |
107 | ||
108 | ret = qcow2_update_header(bs); | |
109 | if (ret < 0) { | |
110 | return ret; | |
111 | } | |
112 | ||
113 | return bdrv_flush(bs); | |
114 | } | |
115 | ||
5f72826e VSO |
116 | static inline void bitmap_table_to_be(uint64_t *bitmap_table, size_t size) |
117 | { | |
118 | size_t i; | |
119 | ||
120 | for (i = 0; i < size; ++i) { | |
121 | cpu_to_be64s(&bitmap_table[i]); | |
122 | } | |
123 | } | |
124 | ||
88ddffae VSO |
125 | static int check_table_entry(uint64_t entry, int cluster_size) |
126 | { | |
127 | uint64_t offset; | |
128 | ||
129 | if (entry & BME_TABLE_ENTRY_RESERVED_MASK) { | |
130 | return -EINVAL; | |
131 | } | |
132 | ||
133 | offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
134 | if (offset != 0) { | |
135 | /* if offset specified, bit 0 is reserved */ | |
136 | if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) { | |
137 | return -EINVAL; | |
138 | } | |
139 | ||
140 | if (offset % cluster_size != 0) { | |
141 | return -EINVAL; | |
142 | } | |
143 | } | |
144 | ||
145 | return 0; | |
146 | } | |
147 | ||
5f72826e VSO |
148 | static int check_constraints_on_bitmap(BlockDriverState *bs, |
149 | const char *name, | |
150 | uint32_t granularity, | |
151 | Error **errp) | |
152 | { | |
153 | BDRVQcow2State *s = bs->opaque; | |
154 | int granularity_bits = ctz32(granularity); | |
155 | int64_t len = bdrv_getlength(bs); | |
156 | ||
157 | assert(granularity > 0); | |
158 | assert((granularity & (granularity - 1)) == 0); | |
159 | ||
160 | if (len < 0) { | |
161 | error_setg_errno(errp, -len, "Failed to get size of '%s'", | |
162 | bdrv_get_device_or_node_name(bs)); | |
163 | return len; | |
164 | } | |
165 | ||
166 | if (granularity_bits > BME_MAX_GRANULARITY_BITS) { | |
167 | error_setg(errp, "Granularity exceeds maximum (%llu bytes)", | |
168 | 1ULL << BME_MAX_GRANULARITY_BITS); | |
169 | return -EINVAL; | |
170 | } | |
171 | if (granularity_bits < BME_MIN_GRANULARITY_BITS) { | |
172 | error_setg(errp, "Granularity is under minimum (%llu bytes)", | |
173 | 1ULL << BME_MIN_GRANULARITY_BITS); | |
174 | return -EINVAL; | |
175 | } | |
176 | ||
177 | if ((len > (uint64_t)BME_MAX_PHYS_SIZE << granularity_bits) || | |
178 | (len > (uint64_t)BME_MAX_TABLE_SIZE * s->cluster_size << | |
179 | granularity_bits)) | |
180 | { | |
181 | error_setg(errp, "Too much space will be occupied by the bitmap. " | |
182 | "Use larger granularity"); | |
183 | return -EINVAL; | |
184 | } | |
185 | ||
186 | if (strlen(name) > BME_MAX_NAME_SIZE) { | |
187 | error_setg(errp, "Name length exceeds maximum (%u characters)", | |
188 | BME_MAX_NAME_SIZE); | |
189 | return -EINVAL; | |
190 | } | |
191 | ||
192 | return 0; | |
193 | } | |
194 | ||
195 | static void clear_bitmap_table(BlockDriverState *bs, uint64_t *bitmap_table, | |
196 | uint32_t bitmap_table_size) | |
197 | { | |
198 | BDRVQcow2State *s = bs->opaque; | |
199 | int i; | |
200 | ||
201 | for (i = 0; i < bitmap_table_size; ++i) { | |
202 | uint64_t addr = bitmap_table[i] & BME_TABLE_ENTRY_OFFSET_MASK; | |
203 | if (!addr) { | |
204 | continue; | |
205 | } | |
206 | ||
207 | qcow2_free_clusters(bs, addr, s->cluster_size, QCOW2_DISCARD_OTHER); | |
208 | bitmap_table[i] = 0; | |
209 | } | |
210 | } | |
211 | ||
88ddffae VSO |
212 | static int bitmap_table_load(BlockDriverState *bs, Qcow2BitmapTable *tb, |
213 | uint64_t **bitmap_table) | |
214 | { | |
215 | int ret; | |
216 | BDRVQcow2State *s = bs->opaque; | |
217 | uint32_t i; | |
218 | uint64_t *table; | |
219 | ||
220 | assert(tb->size != 0); | |
221 | table = g_try_new(uint64_t, tb->size); | |
222 | if (table == NULL) { | |
223 | return -ENOMEM; | |
224 | } | |
225 | ||
226 | assert(tb->size <= BME_MAX_TABLE_SIZE); | |
227 | ret = bdrv_pread(bs->file, tb->offset, | |
228 | table, tb->size * sizeof(uint64_t)); | |
229 | if (ret < 0) { | |
230 | goto fail; | |
231 | } | |
232 | ||
233 | for (i = 0; i < tb->size; ++i) { | |
234 | be64_to_cpus(&table[i]); | |
235 | ret = check_table_entry(table[i], s->cluster_size); | |
236 | if (ret < 0) { | |
237 | goto fail; | |
238 | } | |
239 | } | |
240 | ||
241 | *bitmap_table = table; | |
242 | return 0; | |
243 | ||
244 | fail: | |
245 | g_free(table); | |
246 | ||
247 | return ret; | |
248 | } | |
249 | ||
5f72826e VSO |
250 | static int free_bitmap_clusters(BlockDriverState *bs, Qcow2BitmapTable *tb) |
251 | { | |
252 | int ret; | |
253 | uint64_t *bitmap_table; | |
254 | ||
255 | ret = bitmap_table_load(bs, tb, &bitmap_table); | |
256 | if (ret < 0) { | |
257 | assert(bitmap_table == NULL); | |
258 | return ret; | |
259 | } | |
260 | ||
261 | clear_bitmap_table(bs, bitmap_table, tb->size); | |
262 | qcow2_free_clusters(bs, tb->offset, tb->size * sizeof(uint64_t), | |
263 | QCOW2_DISCARD_OTHER); | |
264 | g_free(bitmap_table); | |
265 | ||
266 | tb->offset = 0; | |
267 | tb->size = 0; | |
268 | ||
269 | return 0; | |
270 | } | |
271 | ||
d1258dd0 VSO |
272 | /* This function returns the number of disk sectors covered by a single qcow2 |
273 | * cluster of bitmap data. */ | |
274 | static uint64_t sectors_covered_by_bitmap_cluster(const BDRVQcow2State *s, | |
275 | const BdrvDirtyBitmap *bitmap) | |
276 | { | |
277 | uint32_t sector_granularity = | |
278 | bdrv_dirty_bitmap_granularity(bitmap) >> BDRV_SECTOR_BITS; | |
279 | ||
280 | return (uint64_t)sector_granularity * (s->cluster_size << 3); | |
281 | } | |
282 | ||
283 | /* load_bitmap_data | |
284 | * @bitmap_table entries must satisfy specification constraints. | |
285 | * @bitmap must be cleared */ | |
286 | static int load_bitmap_data(BlockDriverState *bs, | |
287 | const uint64_t *bitmap_table, | |
288 | uint32_t bitmap_table_size, | |
289 | BdrvDirtyBitmap *bitmap) | |
290 | { | |
291 | int ret = 0; | |
292 | BDRVQcow2State *s = bs->opaque; | |
293 | uint64_t sector, sbc; | |
294 | uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); | |
295 | uint8_t *buf = NULL; | |
296 | uint64_t i, tab_size = | |
297 | size_to_clusters(s, | |
298 | bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size)); | |
299 | ||
300 | if (tab_size != bitmap_table_size || tab_size > BME_MAX_TABLE_SIZE) { | |
301 | return -EINVAL; | |
302 | } | |
303 | ||
304 | buf = g_malloc(s->cluster_size); | |
305 | sbc = sectors_covered_by_bitmap_cluster(s, bitmap); | |
306 | for (i = 0, sector = 0; i < tab_size; ++i, sector += sbc) { | |
307 | uint64_t count = MIN(bm_size - sector, sbc); | |
308 | uint64_t entry = bitmap_table[i]; | |
309 | uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
310 | ||
311 | assert(check_table_entry(entry, s->cluster_size) == 0); | |
312 | ||
313 | if (offset == 0) { | |
314 | if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) { | |
315 | bdrv_dirty_bitmap_deserialize_ones(bitmap, sector, count, | |
316 | false); | |
317 | } else { | |
318 | /* No need to deserialize zeros because the dirty bitmap is | |
319 | * already cleared */ | |
320 | } | |
321 | } else { | |
322 | ret = bdrv_pread(bs->file, offset, buf, s->cluster_size); | |
323 | if (ret < 0) { | |
324 | goto finish; | |
325 | } | |
326 | bdrv_dirty_bitmap_deserialize_part(bitmap, buf, sector, count, | |
327 | false); | |
328 | } | |
329 | } | |
330 | ret = 0; | |
331 | ||
332 | bdrv_dirty_bitmap_deserialize_finish(bitmap); | |
333 | ||
334 | finish: | |
335 | g_free(buf); | |
336 | ||
337 | return ret; | |
338 | } | |
339 | ||
340 | static BdrvDirtyBitmap *load_bitmap(BlockDriverState *bs, | |
341 | Qcow2Bitmap *bm, Error **errp) | |
342 | { | |
343 | int ret; | |
344 | uint64_t *bitmap_table = NULL; | |
345 | uint32_t granularity; | |
346 | BdrvDirtyBitmap *bitmap = NULL; | |
347 | ||
348 | if (bm->flags & BME_FLAG_IN_USE) { | |
349 | error_setg(errp, "Bitmap '%s' is in use", bm->name); | |
350 | goto fail; | |
351 | } | |
352 | ||
353 | ret = bitmap_table_load(bs, &bm->table, &bitmap_table); | |
354 | if (ret < 0) { | |
355 | error_setg_errno(errp, -ret, | |
356 | "Could not read bitmap_table table from image for " | |
357 | "bitmap '%s'", bm->name); | |
358 | goto fail; | |
359 | } | |
360 | ||
361 | granularity = 1U << bm->granularity_bits; | |
362 | bitmap = bdrv_create_dirty_bitmap(bs, granularity, bm->name, errp); | |
363 | if (bitmap == NULL) { | |
364 | goto fail; | |
365 | } | |
366 | ||
367 | ret = load_bitmap_data(bs, bitmap_table, bm->table.size, bitmap); | |
368 | if (ret < 0) { | |
369 | error_setg_errno(errp, -ret, "Could not read bitmap '%s' from image", | |
370 | bm->name); | |
371 | goto fail; | |
372 | } | |
373 | ||
374 | g_free(bitmap_table); | |
375 | return bitmap; | |
376 | ||
377 | fail: | |
378 | g_free(bitmap_table); | |
379 | if (bitmap != NULL) { | |
380 | bdrv_release_dirty_bitmap(bs, bitmap); | |
381 | } | |
382 | ||
383 | return NULL; | |
384 | } | |
385 | ||
88ddffae VSO |
386 | /* |
387 | * Bitmap List | |
388 | */ | |
389 | ||
390 | /* | |
391 | * Bitmap List private functions | |
392 | * Only Bitmap List knows about bitmap directory structure in Qcow2. | |
393 | */ | |
394 | ||
395 | static inline void bitmap_dir_entry_to_cpu(Qcow2BitmapDirEntry *entry) | |
396 | { | |
397 | be64_to_cpus(&entry->bitmap_table_offset); | |
398 | be32_to_cpus(&entry->bitmap_table_size); | |
399 | be32_to_cpus(&entry->flags); | |
400 | be16_to_cpus(&entry->name_size); | |
401 | be32_to_cpus(&entry->extra_data_size); | |
402 | } | |
403 | ||
d1258dd0 VSO |
404 | static inline void bitmap_dir_entry_to_be(Qcow2BitmapDirEntry *entry) |
405 | { | |
406 | cpu_to_be64s(&entry->bitmap_table_offset); | |
407 | cpu_to_be32s(&entry->bitmap_table_size); | |
408 | cpu_to_be32s(&entry->flags); | |
409 | cpu_to_be16s(&entry->name_size); | |
410 | cpu_to_be32s(&entry->extra_data_size); | |
411 | } | |
412 | ||
88ddffae VSO |
413 | static inline int calc_dir_entry_size(size_t name_size, size_t extra_data_size) |
414 | { | |
415 | return align_offset(sizeof(Qcow2BitmapDirEntry) + | |
416 | name_size + extra_data_size, 8); | |
417 | } | |
418 | ||
419 | static inline int dir_entry_size(Qcow2BitmapDirEntry *entry) | |
420 | { | |
421 | return calc_dir_entry_size(entry->name_size, entry->extra_data_size); | |
422 | } | |
423 | ||
424 | static inline const char *dir_entry_name_field(Qcow2BitmapDirEntry *entry) | |
425 | { | |
426 | return (const char *)(entry + 1) + entry->extra_data_size; | |
427 | } | |
428 | ||
429 | static inline char *dir_entry_copy_name(Qcow2BitmapDirEntry *entry) | |
430 | { | |
431 | const char *name_field = dir_entry_name_field(entry); | |
432 | return g_strndup(name_field, entry->name_size); | |
433 | } | |
434 | ||
435 | static inline Qcow2BitmapDirEntry *next_dir_entry(Qcow2BitmapDirEntry *entry) | |
436 | { | |
437 | return (Qcow2BitmapDirEntry *)((uint8_t *)entry + dir_entry_size(entry)); | |
438 | } | |
439 | ||
440 | static int check_dir_entry(BlockDriverState *bs, Qcow2BitmapDirEntry *entry) | |
441 | { | |
442 | BDRVQcow2State *s = bs->opaque; | |
443 | uint64_t phys_bitmap_bytes; | |
444 | int64_t len; | |
445 | ||
446 | bool fail = (entry->bitmap_table_size == 0) || | |
447 | (entry->bitmap_table_offset == 0) || | |
448 | (entry->bitmap_table_offset % s->cluster_size) || | |
449 | (entry->bitmap_table_size > BME_MAX_TABLE_SIZE) || | |
450 | (entry->granularity_bits > BME_MAX_GRANULARITY_BITS) || | |
451 | (entry->granularity_bits < BME_MIN_GRANULARITY_BITS) || | |
452 | (entry->flags & BME_RESERVED_FLAGS) || | |
453 | (entry->name_size > BME_MAX_NAME_SIZE) || | |
454 | (entry->type != BT_DIRTY_TRACKING_BITMAP); | |
455 | ||
456 | if (fail) { | |
457 | return -EINVAL; | |
458 | } | |
459 | ||
460 | phys_bitmap_bytes = (uint64_t)entry->bitmap_table_size * s->cluster_size; | |
461 | len = bdrv_getlength(bs); | |
462 | ||
463 | if (len < 0) { | |
464 | return len; | |
465 | } | |
466 | ||
467 | fail = (phys_bitmap_bytes > BME_MAX_PHYS_SIZE) || | |
468 | (len > ((phys_bitmap_bytes * 8) << entry->granularity_bits)); | |
469 | ||
470 | return fail ? -EINVAL : 0; | |
471 | } | |
472 | ||
d1258dd0 VSO |
473 | static inline void bitmap_directory_to_be(uint8_t *dir, size_t size) |
474 | { | |
475 | uint8_t *end = dir + size; | |
476 | while (dir < end) { | |
477 | Qcow2BitmapDirEntry *e = (Qcow2BitmapDirEntry *)dir; | |
478 | dir += dir_entry_size(e); | |
479 | ||
480 | bitmap_dir_entry_to_be(e); | |
481 | } | |
482 | } | |
483 | ||
88ddffae VSO |
484 | /* |
485 | * Bitmap List public functions | |
486 | */ | |
487 | ||
488 | static void bitmap_free(Qcow2Bitmap *bm) | |
489 | { | |
490 | g_free(bm->name); | |
491 | g_free(bm); | |
492 | } | |
493 | ||
494 | static void bitmap_list_free(Qcow2BitmapList *bm_list) | |
495 | { | |
496 | Qcow2Bitmap *bm; | |
497 | ||
498 | if (bm_list == NULL) { | |
499 | return; | |
500 | } | |
501 | ||
502 | while ((bm = QSIMPLEQ_FIRST(bm_list)) != NULL) { | |
503 | QSIMPLEQ_REMOVE_HEAD(bm_list, entry); | |
504 | bitmap_free(bm); | |
505 | } | |
506 | ||
507 | g_free(bm_list); | |
508 | } | |
509 | ||
510 | static Qcow2BitmapList *bitmap_list_new(void) | |
511 | { | |
512 | Qcow2BitmapList *bm_list = g_new(Qcow2BitmapList, 1); | |
513 | QSIMPLEQ_INIT(bm_list); | |
514 | ||
515 | return bm_list; | |
516 | } | |
517 | ||
d1258dd0 VSO |
518 | static uint32_t bitmap_list_count(Qcow2BitmapList *bm_list) |
519 | { | |
520 | Qcow2Bitmap *bm; | |
521 | uint32_t nb_bitmaps = 0; | |
522 | ||
523 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
524 | nb_bitmaps++; | |
525 | } | |
526 | ||
527 | return nb_bitmaps; | |
528 | } | |
529 | ||
88ddffae VSO |
530 | /* bitmap_list_load |
531 | * Get bitmap list from qcow2 image. Actually reads bitmap directory, | |
532 | * checks it and convert to bitmap list. | |
533 | */ | |
534 | static Qcow2BitmapList *bitmap_list_load(BlockDriverState *bs, uint64_t offset, | |
535 | uint64_t size, Error **errp) | |
536 | { | |
537 | int ret; | |
538 | BDRVQcow2State *s = bs->opaque; | |
539 | uint8_t *dir, *dir_end; | |
540 | Qcow2BitmapDirEntry *e; | |
541 | uint32_t nb_dir_entries = 0; | |
542 | Qcow2BitmapList *bm_list = NULL; | |
543 | ||
544 | if (size == 0) { | |
545 | error_setg(errp, "Requested bitmap directory size is zero"); | |
546 | return NULL; | |
547 | } | |
548 | ||
549 | if (size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
550 | error_setg(errp, "Requested bitmap directory size is too big"); | |
551 | return NULL; | |
552 | } | |
553 | ||
554 | dir = g_try_malloc(size); | |
555 | if (dir == NULL) { | |
556 | error_setg(errp, "Failed to allocate space for bitmap directory"); | |
557 | return NULL; | |
558 | } | |
559 | dir_end = dir + size; | |
560 | ||
561 | ret = bdrv_pread(bs->file, offset, dir, size); | |
562 | if (ret < 0) { | |
563 | error_setg_errno(errp, -ret, "Failed to read bitmap directory"); | |
564 | goto fail; | |
565 | } | |
566 | ||
567 | bm_list = bitmap_list_new(); | |
568 | for (e = (Qcow2BitmapDirEntry *)dir; | |
569 | e < (Qcow2BitmapDirEntry *)dir_end; | |
570 | e = next_dir_entry(e)) | |
571 | { | |
572 | Qcow2Bitmap *bm; | |
573 | ||
574 | if ((uint8_t *)(e + 1) > dir_end) { | |
575 | goto broken_dir; | |
576 | } | |
577 | ||
578 | if (++nb_dir_entries > s->nb_bitmaps) { | |
579 | error_setg(errp, "More bitmaps found than specified in header" | |
580 | " extension"); | |
581 | goto fail; | |
582 | } | |
583 | bitmap_dir_entry_to_cpu(e); | |
584 | ||
585 | if ((uint8_t *)next_dir_entry(e) > dir_end) { | |
586 | goto broken_dir; | |
587 | } | |
588 | ||
589 | if (e->extra_data_size != 0) { | |
590 | error_setg(errp, "Bitmap extra data is not supported"); | |
591 | goto fail; | |
592 | } | |
593 | ||
594 | ret = check_dir_entry(bs, e); | |
595 | if (ret < 0) { | |
596 | error_setg(errp, "Bitmap '%.*s' doesn't satisfy the constraints", | |
597 | e->name_size, dir_entry_name_field(e)); | |
598 | goto fail; | |
599 | } | |
600 | ||
601 | bm = g_new(Qcow2Bitmap, 1); | |
602 | bm->table.offset = e->bitmap_table_offset; | |
603 | bm->table.size = e->bitmap_table_size; | |
604 | bm->flags = e->flags; | |
605 | bm->granularity_bits = e->granularity_bits; | |
606 | bm->name = dir_entry_copy_name(e); | |
607 | QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry); | |
608 | } | |
609 | ||
610 | if (nb_dir_entries != s->nb_bitmaps) { | |
611 | error_setg(errp, "Less bitmaps found than specified in header" | |
612 | " extension"); | |
613 | goto fail; | |
614 | } | |
615 | ||
616 | if ((uint8_t *)e != dir_end) { | |
617 | goto broken_dir; | |
618 | } | |
619 | ||
620 | g_free(dir); | |
621 | return bm_list; | |
622 | ||
623 | broken_dir: | |
624 | ret = -EINVAL; | |
625 | error_setg(errp, "Broken bitmap directory"); | |
626 | ||
627 | fail: | |
628 | g_free(dir); | |
629 | bitmap_list_free(bm_list); | |
630 | ||
631 | return NULL; | |
632 | } | |
633 | ||
634 | int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, | |
635 | void **refcount_table, | |
636 | int64_t *refcount_table_size) | |
637 | { | |
638 | int ret; | |
639 | BDRVQcow2State *s = bs->opaque; | |
640 | Qcow2BitmapList *bm_list; | |
641 | Qcow2Bitmap *bm; | |
642 | ||
643 | if (s->nb_bitmaps == 0) { | |
644 | return 0; | |
645 | } | |
646 | ||
647 | ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_size, | |
648 | s->bitmap_directory_offset, | |
649 | s->bitmap_directory_size); | |
650 | if (ret < 0) { | |
651 | return ret; | |
652 | } | |
653 | ||
654 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
655 | s->bitmap_directory_size, NULL); | |
656 | if (bm_list == NULL) { | |
657 | res->corruptions++; | |
658 | return -EINVAL; | |
659 | } | |
660 | ||
661 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
662 | uint64_t *bitmap_table = NULL; | |
663 | int i; | |
664 | ||
665 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
666 | refcount_table, refcount_table_size, | |
667 | bm->table.offset, | |
668 | bm->table.size * sizeof(uint64_t)); | |
669 | if (ret < 0) { | |
670 | goto out; | |
671 | } | |
672 | ||
673 | ret = bitmap_table_load(bs, &bm->table, &bitmap_table); | |
674 | if (ret < 0) { | |
675 | res->corruptions++; | |
676 | goto out; | |
677 | } | |
678 | ||
679 | for (i = 0; i < bm->table.size; ++i) { | |
680 | uint64_t entry = bitmap_table[i]; | |
681 | uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
682 | ||
683 | if (check_table_entry(entry, s->cluster_size) < 0) { | |
684 | res->corruptions++; | |
685 | continue; | |
686 | } | |
687 | ||
688 | if (offset == 0) { | |
689 | continue; | |
690 | } | |
691 | ||
692 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
693 | refcount_table, refcount_table_size, | |
694 | offset, s->cluster_size); | |
695 | if (ret < 0) { | |
696 | g_free(bitmap_table); | |
697 | goto out; | |
698 | } | |
699 | } | |
700 | ||
701 | g_free(bitmap_table); | |
702 | } | |
703 | ||
704 | out: | |
705 | bitmap_list_free(bm_list); | |
706 | ||
707 | return ret; | |
708 | } | |
d1258dd0 VSO |
709 | |
710 | /* bitmap_list_store | |
711 | * Store bitmap list to qcow2 image as a bitmap directory. | |
712 | * Everything is checked. | |
713 | */ | |
714 | static int bitmap_list_store(BlockDriverState *bs, Qcow2BitmapList *bm_list, | |
715 | uint64_t *offset, uint64_t *size, bool in_place) | |
716 | { | |
717 | int ret; | |
718 | uint8_t *dir; | |
719 | int64_t dir_offset = 0; | |
720 | uint64_t dir_size = 0; | |
721 | Qcow2Bitmap *bm; | |
722 | Qcow2BitmapDirEntry *e; | |
723 | ||
724 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
725 | dir_size += calc_dir_entry_size(strlen(bm->name), 0); | |
726 | } | |
727 | ||
728 | if (dir_size == 0 || dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
729 | return -EINVAL; | |
730 | } | |
731 | ||
732 | if (in_place) { | |
733 | if (*size != dir_size || *offset == 0) { | |
734 | return -EINVAL; | |
735 | } | |
736 | ||
737 | dir_offset = *offset; | |
738 | } | |
739 | ||
740 | dir = g_try_malloc(dir_size); | |
741 | if (dir == NULL) { | |
742 | return -ENOMEM; | |
743 | } | |
744 | ||
745 | e = (Qcow2BitmapDirEntry *)dir; | |
746 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
747 | e->bitmap_table_offset = bm->table.offset; | |
748 | e->bitmap_table_size = bm->table.size; | |
749 | e->flags = bm->flags; | |
750 | e->type = BT_DIRTY_TRACKING_BITMAP; | |
751 | e->granularity_bits = bm->granularity_bits; | |
752 | e->name_size = strlen(bm->name); | |
753 | e->extra_data_size = 0; | |
754 | memcpy(e + 1, bm->name, e->name_size); | |
755 | ||
756 | if (check_dir_entry(bs, e) < 0) { | |
757 | ret = -EINVAL; | |
758 | goto fail; | |
759 | } | |
760 | ||
761 | e = next_dir_entry(e); | |
762 | } | |
763 | ||
764 | bitmap_directory_to_be(dir, dir_size); | |
765 | ||
766 | if (!in_place) { | |
767 | dir_offset = qcow2_alloc_clusters(bs, dir_size); | |
768 | if (dir_offset < 0) { | |
769 | ret = dir_offset; | |
770 | goto fail; | |
771 | } | |
772 | } | |
773 | ||
774 | ret = qcow2_pre_write_overlap_check(bs, 0, dir_offset, dir_size); | |
775 | if (ret < 0) { | |
776 | goto fail; | |
777 | } | |
778 | ||
779 | ret = bdrv_pwrite(bs->file, dir_offset, dir, dir_size); | |
780 | if (ret < 0) { | |
781 | goto fail; | |
782 | } | |
783 | ||
784 | g_free(dir); | |
785 | ||
786 | if (!in_place) { | |
787 | *size = dir_size; | |
788 | *offset = dir_offset; | |
789 | } | |
790 | ||
791 | return 0; | |
792 | ||
793 | fail: | |
794 | g_free(dir); | |
795 | ||
796 | if (!in_place && dir_offset > 0) { | |
797 | qcow2_free_clusters(bs, dir_offset, dir_size, QCOW2_DISCARD_OTHER); | |
798 | } | |
799 | ||
800 | return ret; | |
801 | } | |
802 | ||
803 | /* | |
804 | * Bitmap List end | |
805 | */ | |
806 | ||
807 | static int update_ext_header_and_dir_in_place(BlockDriverState *bs, | |
808 | Qcow2BitmapList *bm_list) | |
809 | { | |
810 | BDRVQcow2State *s = bs->opaque; | |
811 | int ret; | |
812 | ||
813 | if (!(s->autoclear_features & QCOW2_AUTOCLEAR_BITMAPS) || | |
814 | bm_list == NULL || QSIMPLEQ_EMPTY(bm_list) || | |
815 | bitmap_list_count(bm_list) != s->nb_bitmaps) | |
816 | { | |
817 | return -EINVAL; | |
818 | } | |
819 | ||
820 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
821 | ret = update_header_sync(bs); | |
822 | if (ret < 0) { | |
823 | /* Two variants are possible here: | |
824 | * 1. Autoclear flag is dropped, all bitmaps will be lost. | |
825 | * 2. Autoclear flag is not dropped, old state is left. | |
826 | */ | |
827 | return ret; | |
828 | } | |
829 | ||
830 | /* autoclear bit is not set, so we can safely update bitmap directory */ | |
831 | ||
832 | ret = bitmap_list_store(bs, bm_list, &s->bitmap_directory_offset, | |
833 | &s->bitmap_directory_size, true); | |
834 | if (ret < 0) { | |
835 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
836 | * qemu-img check */ | |
837 | return ret; | |
838 | } | |
839 | ||
840 | ret = update_header_sync(bs); | |
841 | if (ret < 0) { | |
842 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
843 | * qemu-img check */ | |
844 | return ret; | |
845 | } | |
846 | ||
847 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
848 | return update_header_sync(bs); | |
849 | /* If final update_header_sync() fails, two variants are possible: | |
850 | * 1. Autoclear flag is not set, all bitmaps will be lost. | |
851 | * 2. Autoclear flag is set, header and directory are successfully updated. | |
852 | */ | |
853 | } | |
854 | ||
5f72826e VSO |
855 | static int update_ext_header_and_dir(BlockDriverState *bs, |
856 | Qcow2BitmapList *bm_list) | |
857 | { | |
858 | BDRVQcow2State *s = bs->opaque; | |
859 | int ret; | |
860 | uint64_t new_offset = 0; | |
861 | uint64_t new_size = 0; | |
862 | uint32_t new_nb_bitmaps = 0; | |
863 | uint64_t old_offset = s->bitmap_directory_offset; | |
864 | uint64_t old_size = s->bitmap_directory_size; | |
865 | uint32_t old_nb_bitmaps = s->nb_bitmaps; | |
866 | uint64_t old_autocl = s->autoclear_features; | |
867 | ||
868 | if (bm_list != NULL && !QSIMPLEQ_EMPTY(bm_list)) { | |
869 | new_nb_bitmaps = bitmap_list_count(bm_list); | |
870 | ||
871 | if (new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
872 | return -EINVAL; | |
873 | } | |
874 | ||
875 | ret = bitmap_list_store(bs, bm_list, &new_offset, &new_size, false); | |
876 | if (ret < 0) { | |
877 | return ret; | |
878 | } | |
879 | ||
880 | ret = bdrv_flush(bs->file->bs); | |
881 | if (ret < 0) { | |
882 | goto fail; | |
883 | } | |
884 | ||
885 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
886 | } else { | |
887 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
888 | } | |
889 | ||
890 | s->bitmap_directory_offset = new_offset; | |
891 | s->bitmap_directory_size = new_size; | |
892 | s->nb_bitmaps = new_nb_bitmaps; | |
893 | ||
894 | ret = update_header_sync(bs); | |
895 | if (ret < 0) { | |
896 | goto fail; | |
897 | } | |
898 | ||
899 | if (old_size > 0) { | |
900 | qcow2_free_clusters(bs, old_offset, old_size, QCOW2_DISCARD_OTHER); | |
901 | } | |
902 | ||
903 | return 0; | |
904 | ||
905 | fail: | |
906 | if (new_offset > 0) { | |
907 | qcow2_free_clusters(bs, new_offset, new_size, QCOW2_DISCARD_OTHER); | |
908 | } | |
909 | ||
910 | s->bitmap_directory_offset = old_offset; | |
911 | s->bitmap_directory_size = old_size; | |
912 | s->nb_bitmaps = old_nb_bitmaps; | |
913 | s->autoclear_features = old_autocl; | |
914 | ||
915 | return ret; | |
916 | } | |
917 | ||
d1258dd0 VSO |
918 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ |
919 | static void release_dirty_bitmap_helper(gpointer bitmap, | |
920 | gpointer bs) | |
921 | { | |
922 | bdrv_release_dirty_bitmap(bs, bitmap); | |
923 | } | |
924 | ||
925 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ | |
926 | static void set_readonly_helper(gpointer bitmap, gpointer value) | |
927 | { | |
928 | bdrv_dirty_bitmap_set_readonly(bitmap, (bool)value); | |
929 | } | |
930 | ||
931 | /* qcow2_load_autoloading_dirty_bitmaps() | |
932 | * Return value is a hint for caller: true means that the Qcow2 header was | |
933 | * updated. (false doesn't mean that the header should be updated by the | |
934 | * caller, it just means that updating was not needed or the image cannot be | |
935 | * written to). | |
936 | * On failure the function returns false. | |
937 | */ | |
938 | bool qcow2_load_autoloading_dirty_bitmaps(BlockDriverState *bs, Error **errp) | |
939 | { | |
940 | BDRVQcow2State *s = bs->opaque; | |
941 | Qcow2BitmapList *bm_list; | |
942 | Qcow2Bitmap *bm; | |
943 | GSList *created_dirty_bitmaps = NULL; | |
944 | bool header_updated = false; | |
945 | ||
946 | if (s->nb_bitmaps == 0) { | |
947 | /* No bitmaps - nothing to do */ | |
948 | return false; | |
949 | } | |
950 | ||
951 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
952 | s->bitmap_directory_size, errp); | |
953 | if (bm_list == NULL) { | |
954 | return false; | |
955 | } | |
956 | ||
957 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
958 | if ((bm->flags & BME_FLAG_AUTO) && !(bm->flags & BME_FLAG_IN_USE)) { | |
959 | BdrvDirtyBitmap *bitmap = load_bitmap(bs, bm, errp); | |
960 | if (bitmap == NULL) { | |
961 | goto fail; | |
962 | } | |
a0319aac | 963 | |
a88b179f | 964 | bdrv_dirty_bitmap_set_persistance(bitmap, true); |
a0319aac | 965 | bdrv_dirty_bitmap_set_autoload(bitmap, true); |
d1258dd0 VSO |
966 | bm->flags |= BME_FLAG_IN_USE; |
967 | created_dirty_bitmaps = | |
968 | g_slist_append(created_dirty_bitmaps, bitmap); | |
969 | } | |
970 | } | |
971 | ||
972 | if (created_dirty_bitmaps != NULL) { | |
973 | if (can_write(bs)) { | |
974 | /* in_use flags must be updated */ | |
975 | int ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
976 | if (ret < 0) { | |
977 | error_setg_errno(errp, -ret, "Can't update bitmap directory"); | |
978 | goto fail; | |
979 | } | |
980 | header_updated = true; | |
981 | } else { | |
982 | g_slist_foreach(created_dirty_bitmaps, set_readonly_helper, | |
983 | (gpointer)true); | |
984 | } | |
985 | } | |
986 | ||
987 | g_slist_free(created_dirty_bitmaps); | |
988 | bitmap_list_free(bm_list); | |
989 | ||
990 | return header_updated; | |
991 | ||
992 | fail: | |
993 | g_slist_foreach(created_dirty_bitmaps, release_dirty_bitmap_helper, bs); | |
994 | g_slist_free(created_dirty_bitmaps); | |
995 | bitmap_list_free(bm_list); | |
996 | ||
997 | return false; | |
998 | } | |
1b6b0562 VSO |
999 | |
1000 | int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp) | |
1001 | { | |
1002 | BDRVQcow2State *s = bs->opaque; | |
1003 | Qcow2BitmapList *bm_list; | |
1004 | Qcow2Bitmap *bm; | |
1005 | GSList *ro_dirty_bitmaps = NULL; | |
1006 | int ret = 0; | |
1007 | ||
1008 | if (s->nb_bitmaps == 0) { | |
1009 | /* No bitmaps - nothing to do */ | |
1010 | return 0; | |
1011 | } | |
1012 | ||
1013 | if (!can_write(bs)) { | |
1014 | error_setg(errp, "Can't write to the image on reopening bitmaps rw"); | |
1015 | return -EINVAL; | |
1016 | } | |
1017 | ||
1018 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1019 | s->bitmap_directory_size, errp); | |
1020 | if (bm_list == NULL) { | |
1021 | return -EINVAL; | |
1022 | } | |
1023 | ||
1024 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1025 | if (!(bm->flags & BME_FLAG_IN_USE)) { | |
1026 | BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name); | |
1027 | if (bitmap == NULL) { | |
1028 | continue; | |
1029 | } | |
1030 | ||
1031 | if (!bdrv_dirty_bitmap_readonly(bitmap)) { | |
1032 | error_setg(errp, "Bitmap %s is not readonly but not marked" | |
1033 | "'IN_USE' in the image. Something went wrong," | |
1034 | "all the bitmaps may be corrupted", bm->name); | |
1035 | ret = -EINVAL; | |
1036 | goto out; | |
1037 | } | |
1038 | ||
1039 | bm->flags |= BME_FLAG_IN_USE; | |
1040 | ro_dirty_bitmaps = g_slist_append(ro_dirty_bitmaps, bitmap); | |
1041 | } | |
1042 | } | |
1043 | ||
1044 | if (ro_dirty_bitmaps != NULL) { | |
1045 | /* in_use flags must be updated */ | |
1046 | ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
1047 | if (ret < 0) { | |
1048 | error_setg_errno(errp, -ret, "Can't update bitmap directory"); | |
1049 | goto out; | |
1050 | } | |
1051 | g_slist_foreach(ro_dirty_bitmaps, set_readonly_helper, false); | |
1052 | } | |
1053 | ||
1054 | out: | |
1055 | g_slist_free(ro_dirty_bitmaps); | |
1056 | bitmap_list_free(bm_list); | |
1057 | ||
1058 | return ret; | |
1059 | } | |
5f72826e VSO |
1060 | |
1061 | /* store_bitmap_data() | |
1062 | * Store bitmap to image, filling bitmap table accordingly. | |
1063 | */ | |
1064 | static uint64_t *store_bitmap_data(BlockDriverState *bs, | |
1065 | BdrvDirtyBitmap *bitmap, | |
1066 | uint32_t *bitmap_table_size, Error **errp) | |
1067 | { | |
1068 | int ret; | |
1069 | BDRVQcow2State *s = bs->opaque; | |
1070 | int64_t sector; | |
1071 | uint64_t sbc; | |
1072 | uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); | |
1073 | const char *bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1074 | uint8_t *buf = NULL; | |
1075 | BdrvDirtyBitmapIter *dbi; | |
1076 | uint64_t *tb; | |
1077 | uint64_t tb_size = | |
1078 | size_to_clusters(s, | |
1079 | bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size)); | |
1080 | ||
1081 | if (tb_size > BME_MAX_TABLE_SIZE || | |
1082 | tb_size * s->cluster_size > BME_MAX_PHYS_SIZE) | |
1083 | { | |
1084 | error_setg(errp, "Bitmap '%s' is too big", bm_name); | |
1085 | return NULL; | |
1086 | } | |
1087 | ||
1088 | tb = g_try_new0(uint64_t, tb_size); | |
1089 | if (tb == NULL) { | |
1090 | error_setg(errp, "No memory"); | |
1091 | return NULL; | |
1092 | } | |
1093 | ||
1094 | dbi = bdrv_dirty_iter_new(bitmap, 0); | |
1095 | buf = g_malloc(s->cluster_size); | |
1096 | sbc = sectors_covered_by_bitmap_cluster(s, bitmap); | |
1097 | assert(DIV_ROUND_UP(bm_size, sbc) == tb_size); | |
1098 | ||
1099 | while ((sector = bdrv_dirty_iter_next(dbi)) != -1) { | |
1100 | uint64_t cluster = sector / sbc; | |
1101 | uint64_t end, write_size; | |
1102 | int64_t off; | |
1103 | ||
1104 | sector = cluster * sbc; | |
1105 | end = MIN(bm_size, sector + sbc); | |
1106 | write_size = | |
1107 | bdrv_dirty_bitmap_serialization_size(bitmap, sector, end - sector); | |
1108 | assert(write_size <= s->cluster_size); | |
1109 | ||
1110 | off = qcow2_alloc_clusters(bs, s->cluster_size); | |
1111 | if (off < 0) { | |
1112 | error_setg_errno(errp, -off, | |
1113 | "Failed to allocate clusters for bitmap '%s'", | |
1114 | bm_name); | |
1115 | goto fail; | |
1116 | } | |
1117 | tb[cluster] = off; | |
1118 | ||
1119 | bdrv_dirty_bitmap_serialize_part(bitmap, buf, sector, end - sector); | |
1120 | if (write_size < s->cluster_size) { | |
1121 | memset(buf + write_size, 0, s->cluster_size - write_size); | |
1122 | } | |
1123 | ||
1124 | ret = qcow2_pre_write_overlap_check(bs, 0, off, s->cluster_size); | |
1125 | if (ret < 0) { | |
1126 | error_setg_errno(errp, -ret, "Qcow2 overlap check failed"); | |
1127 | goto fail; | |
1128 | } | |
1129 | ||
1130 | ret = bdrv_pwrite(bs->file, off, buf, s->cluster_size); | |
1131 | if (ret < 0) { | |
1132 | error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file", | |
1133 | bm_name); | |
1134 | goto fail; | |
1135 | } | |
1136 | ||
1137 | if (end >= bm_size) { | |
1138 | break; | |
1139 | } | |
1140 | ||
1141 | bdrv_set_dirty_iter(dbi, end); | |
1142 | } | |
1143 | ||
1144 | *bitmap_table_size = tb_size; | |
1145 | g_free(buf); | |
1146 | bdrv_dirty_iter_free(dbi); | |
1147 | ||
1148 | return tb; | |
1149 | ||
1150 | fail: | |
1151 | clear_bitmap_table(bs, tb, tb_size); | |
1152 | g_free(buf); | |
1153 | bdrv_dirty_iter_free(dbi); | |
1154 | g_free(tb); | |
1155 | ||
1156 | return NULL; | |
1157 | } | |
1158 | ||
1159 | /* store_bitmap() | |
1160 | * Store bm->dirty_bitmap to qcow2. | |
1161 | * Set bm->table_offset and bm->table_size accordingly. | |
1162 | */ | |
1163 | static int store_bitmap(BlockDriverState *bs, Qcow2Bitmap *bm, Error **errp) | |
1164 | { | |
1165 | int ret; | |
1166 | uint64_t *tb; | |
1167 | int64_t tb_offset; | |
1168 | uint32_t tb_size; | |
1169 | BdrvDirtyBitmap *bitmap = bm->dirty_bitmap; | |
1170 | const char *bm_name; | |
1171 | ||
1172 | assert(bitmap != NULL); | |
1173 | ||
1174 | bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1175 | ||
1176 | tb = store_bitmap_data(bs, bitmap, &tb_size, errp); | |
1177 | if (tb == NULL) { | |
1178 | return -EINVAL; | |
1179 | } | |
1180 | ||
1181 | assert(tb_size <= BME_MAX_TABLE_SIZE); | |
1182 | tb_offset = qcow2_alloc_clusters(bs, tb_size * sizeof(tb[0])); | |
1183 | if (tb_offset < 0) { | |
1184 | error_setg_errno(errp, -tb_offset, | |
1185 | "Failed to allocate clusters for bitmap '%s'", | |
1186 | bm_name); | |
1187 | ret = tb_offset; | |
1188 | goto fail; | |
1189 | } | |
1190 | ||
1191 | ret = qcow2_pre_write_overlap_check(bs, 0, tb_offset, | |
1192 | tb_size * sizeof(tb[0])); | |
1193 | if (ret < 0) { | |
1194 | error_setg_errno(errp, -ret, "Qcow2 overlap check failed"); | |
1195 | goto fail; | |
1196 | } | |
1197 | ||
1198 | bitmap_table_to_be(tb, tb_size); | |
1199 | ret = bdrv_pwrite(bs->file, tb_offset, tb, tb_size * sizeof(tb[0])); | |
1200 | if (ret < 0) { | |
1201 | error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file", | |
1202 | bm_name); | |
1203 | goto fail; | |
1204 | } | |
1205 | ||
1206 | g_free(tb); | |
1207 | ||
1208 | bm->table.offset = tb_offset; | |
1209 | bm->table.size = tb_size; | |
1210 | ||
1211 | return 0; | |
1212 | ||
1213 | fail: | |
1214 | clear_bitmap_table(bs, tb, tb_size); | |
1215 | ||
1216 | if (tb_offset > 0) { | |
1217 | qcow2_free_clusters(bs, tb_offset, tb_size * sizeof(tb[0]), | |
1218 | QCOW2_DISCARD_OTHER); | |
1219 | } | |
1220 | ||
1221 | g_free(tb); | |
1222 | ||
1223 | return ret; | |
1224 | } | |
1225 | ||
1226 | static Qcow2Bitmap *find_bitmap_by_name(Qcow2BitmapList *bm_list, | |
1227 | const char *name) | |
1228 | { | |
1229 | Qcow2Bitmap *bm; | |
1230 | ||
1231 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1232 | if (strcmp(name, bm->name) == 0) { | |
1233 | return bm; | |
1234 | } | |
1235 | } | |
1236 | ||
1237 | return NULL; | |
1238 | } | |
1239 | ||
469c71ed VSO |
1240 | void qcow2_remove_persistent_dirty_bitmap(BlockDriverState *bs, |
1241 | const char *name, | |
1242 | Error **errp) | |
1243 | { | |
1244 | int ret; | |
1245 | BDRVQcow2State *s = bs->opaque; | |
1246 | Qcow2Bitmap *bm; | |
1247 | Qcow2BitmapList *bm_list; | |
1248 | ||
1249 | if (s->nb_bitmaps == 0) { | |
1250 | /* Absence of the bitmap is not an error: see explanation above | |
1251 | * bdrv_remove_persistent_dirty_bitmap() definition. */ | |
1252 | return; | |
1253 | } | |
1254 | ||
1255 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1256 | s->bitmap_directory_size, errp); | |
1257 | if (bm_list == NULL) { | |
1258 | return; | |
1259 | } | |
1260 | ||
1261 | bm = find_bitmap_by_name(bm_list, name); | |
1262 | if (bm == NULL) { | |
1263 | goto fail; | |
1264 | } | |
1265 | ||
1266 | QSIMPLEQ_REMOVE(bm_list, bm, Qcow2Bitmap, entry); | |
1267 | ||
1268 | ret = update_ext_header_and_dir(bs, bm_list); | |
1269 | if (ret < 0) { | |
1270 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
1271 | goto fail; | |
1272 | } | |
1273 | ||
1274 | free_bitmap_clusters(bs, &bm->table); | |
1275 | ||
1276 | fail: | |
1277 | bitmap_free(bm); | |
1278 | bitmap_list_free(bm_list); | |
1279 | } | |
1280 | ||
5f72826e VSO |
1281 | void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp) |
1282 | { | |
1283 | BdrvDirtyBitmap *bitmap; | |
1284 | BDRVQcow2State *s = bs->opaque; | |
1285 | uint32_t new_nb_bitmaps = s->nb_bitmaps; | |
1286 | uint64_t new_dir_size = s->bitmap_directory_size; | |
1287 | int ret; | |
1288 | Qcow2BitmapList *bm_list; | |
1289 | Qcow2Bitmap *bm; | |
1290 | Qcow2BitmapTableList drop_tables; | |
1291 | Qcow2BitmapTable *tb, *tb_next; | |
1292 | ||
1293 | if (!bdrv_has_changed_persistent_bitmaps(bs)) { | |
1294 | /* nothing to do */ | |
1295 | return; | |
1296 | } | |
1297 | ||
1298 | if (!can_write(bs)) { | |
1299 | error_setg(errp, "No write access"); | |
1300 | return; | |
1301 | } | |
1302 | ||
1303 | QSIMPLEQ_INIT(&drop_tables); | |
1304 | ||
1305 | if (s->nb_bitmaps == 0) { | |
1306 | bm_list = bitmap_list_new(); | |
1307 | } else { | |
1308 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1309 | s->bitmap_directory_size, errp); | |
1310 | if (bm_list == NULL) { | |
1311 | return; | |
1312 | } | |
1313 | } | |
1314 | ||
1315 | /* check constraints and names */ | |
1316 | for (bitmap = bdrv_dirty_bitmap_next(bs, NULL); bitmap != NULL; | |
1317 | bitmap = bdrv_dirty_bitmap_next(bs, bitmap)) | |
1318 | { | |
1319 | const char *name = bdrv_dirty_bitmap_name(bitmap); | |
1320 | uint32_t granularity = bdrv_dirty_bitmap_granularity(bitmap); | |
1321 | Qcow2Bitmap *bm; | |
1322 | ||
1323 | if (!bdrv_dirty_bitmap_get_persistance(bitmap) || | |
1324 | bdrv_dirty_bitmap_readonly(bitmap)) | |
1325 | { | |
1326 | continue; | |
1327 | } | |
1328 | ||
1329 | if (check_constraints_on_bitmap(bs, name, granularity, errp) < 0) { | |
1330 | error_prepend(errp, "Bitmap '%s' doesn't satisfy the constraints: ", | |
1331 | name); | |
1332 | goto fail; | |
1333 | } | |
1334 | ||
1335 | bm = find_bitmap_by_name(bm_list, name); | |
1336 | if (bm == NULL) { | |
1337 | if (++new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
1338 | error_setg(errp, "Too many persistent bitmaps"); | |
1339 | goto fail; | |
1340 | } | |
1341 | ||
1342 | new_dir_size += calc_dir_entry_size(strlen(name), 0); | |
1343 | if (new_dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
1344 | error_setg(errp, "Bitmap directory is too large"); | |
1345 | goto fail; | |
1346 | } | |
1347 | ||
1348 | bm = g_new0(Qcow2Bitmap, 1); | |
1349 | bm->name = g_strdup(name); | |
1350 | QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry); | |
1351 | } else { | |
1352 | if (!(bm->flags & BME_FLAG_IN_USE)) { | |
1353 | error_setg(errp, "Bitmap '%s' already exists in the image", | |
1354 | name); | |
1355 | goto fail; | |
1356 | } | |
1357 | tb = g_memdup(&bm->table, sizeof(bm->table)); | |
1358 | bm->table.offset = 0; | |
1359 | bm->table.size = 0; | |
1360 | QSIMPLEQ_INSERT_TAIL(&drop_tables, tb, entry); | |
1361 | } | |
1362 | bm->flags = bdrv_dirty_bitmap_get_autoload(bitmap) ? BME_FLAG_AUTO : 0; | |
1363 | bm->granularity_bits = ctz32(bdrv_dirty_bitmap_granularity(bitmap)); | |
1364 | bm->dirty_bitmap = bitmap; | |
1365 | } | |
1366 | ||
1367 | /* allocate clusters and store bitmaps */ | |
1368 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1369 | if (bm->dirty_bitmap == NULL) { | |
1370 | continue; | |
1371 | } | |
1372 | ||
1373 | ret = store_bitmap(bs, bm, errp); | |
1374 | if (ret < 0) { | |
1375 | goto fail; | |
1376 | } | |
1377 | } | |
1378 | ||
1379 | ret = update_ext_header_and_dir(bs, bm_list); | |
1380 | if (ret < 0) { | |
1381 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
1382 | goto fail; | |
1383 | } | |
1384 | ||
1385 | /* Bitmap directory was successfully updated, so, old data can be dropped. | |
1386 | * TODO it is better to reuse these clusters */ | |
1387 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1388 | free_bitmap_clusters(bs, tb); | |
1389 | g_free(tb); | |
1390 | } | |
1391 | ||
1392 | bitmap_list_free(bm_list); | |
1393 | return; | |
1394 | ||
1395 | fail: | |
1396 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1397 | if (bm->dirty_bitmap == NULL || bm->table.offset == 0) { | |
1398 | continue; | |
1399 | } | |
1400 | ||
1401 | free_bitmap_clusters(bs, &bm->table); | |
1402 | } | |
1403 | ||
1404 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1405 | g_free(tb); | |
1406 | } | |
1407 | ||
1408 | bitmap_list_free(bm_list); | |
1409 | } | |
169b8793 VSO |
1410 | |
1411 | int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp) | |
1412 | { | |
1413 | BdrvDirtyBitmap *bitmap; | |
1414 | Error *local_err = NULL; | |
1415 | ||
1416 | qcow2_store_persistent_dirty_bitmaps(bs, &local_err); | |
1417 | if (local_err != NULL) { | |
1418 | error_propagate(errp, local_err); | |
1419 | return -EINVAL; | |
1420 | } | |
1421 | ||
1422 | for (bitmap = bdrv_dirty_bitmap_next(bs, NULL); bitmap != NULL; | |
1423 | bitmap = bdrv_dirty_bitmap_next(bs, bitmap)) | |
1424 | { | |
1425 | if (bdrv_dirty_bitmap_get_persistance(bitmap)) { | |
1426 | bdrv_dirty_bitmap_set_readonly(bitmap, true); | |
1427 | } | |
1428 | } | |
1429 | ||
1430 | return 0; | |
1431 | } | |
da0eb242 VSO |
1432 | |
1433 | bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs, | |
1434 | const char *name, | |
1435 | uint32_t granularity, | |
1436 | Error **errp) | |
1437 | { | |
1438 | BDRVQcow2State *s = bs->opaque; | |
1439 | bool found; | |
1440 | Qcow2BitmapList *bm_list; | |
1441 | ||
1442 | if (check_constraints_on_bitmap(bs, name, granularity, errp) != 0) { | |
1443 | goto fail; | |
1444 | } | |
1445 | ||
1446 | if (s->nb_bitmaps == 0) { | |
1447 | return true; | |
1448 | } | |
1449 | ||
1450 | if (s->nb_bitmaps >= QCOW2_MAX_BITMAPS) { | |
1451 | error_setg(errp, | |
1452 | "Maximum number of persistent bitmaps is already reached"); | |
1453 | goto fail; | |
1454 | } | |
1455 | ||
1456 | if (s->bitmap_directory_size + calc_dir_entry_size(strlen(name), 0) > | |
1457 | QCOW2_MAX_BITMAP_DIRECTORY_SIZE) | |
1458 | { | |
1459 | error_setg(errp, "Not enough space in the bitmap directory"); | |
1460 | goto fail; | |
1461 | } | |
1462 | ||
1463 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1464 | s->bitmap_directory_size, errp); | |
1465 | if (bm_list == NULL) { | |
1466 | goto fail; | |
1467 | } | |
1468 | ||
1469 | found = find_bitmap_by_name(bm_list, name); | |
1470 | bitmap_list_free(bm_list); | |
1471 | if (found) { | |
1472 | error_setg(errp, "Bitmap with the same name is already stored"); | |
1473 | goto fail; | |
1474 | } | |
1475 | ||
1476 | return true; | |
1477 | ||
1478 | fail: | |
1479 | error_prepend(errp, "Can't make bitmap '%s' persistent in '%s': ", | |
1480 | name, bdrv_get_device_or_node_name(bs)); | |
1481 | return false; | |
1482 | } |