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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 | 31 | |
0d8c41da | 32 | #include "qcow2.h" |
88ddffae VSO |
33 | |
34 | /* NOTICE: BME here means Bitmaps Extension and used as a namespace for | |
35 | * _internal_ constants. Please do not use this _internal_ abbreviation for | |
36 | * other needs and/or outside of this file. */ | |
37 | ||
38 | /* Bitmap directory entry constraints */ | |
39 | #define BME_MAX_TABLE_SIZE 0x8000000 | |
40 | #define BME_MAX_PHYS_SIZE 0x20000000 /* restrict BdrvDirtyBitmap size in RAM */ | |
41 | #define BME_MAX_GRANULARITY_BITS 31 | |
42 | #define BME_MIN_GRANULARITY_BITS 9 | |
43 | #define BME_MAX_NAME_SIZE 1023 | |
44 | ||
02b1ecfa AG |
45 | /* Size of bitmap table entries */ |
46 | #define BME_TABLE_ENTRY_SIZE (sizeof(uint64_t)) | |
47 | ||
cf7c49cf EB |
48 | QEMU_BUILD_BUG_ON(BME_MAX_NAME_SIZE != BDRV_BITMAP_MAX_NAME_SIZE); |
49 | ||
5f72826e VSO |
50 | #if BME_MAX_TABLE_SIZE * 8ULL > INT_MAX |
51 | #error In the code bitmap table physical size assumed to fit into int | |
52 | #endif | |
53 | ||
88ddffae VSO |
54 | /* Bitmap directory entry flags */ |
55 | #define BME_RESERVED_FLAGS 0xfffffffcU | |
d1258dd0 VSO |
56 | #define BME_FLAG_IN_USE (1U << 0) |
57 | #define BME_FLAG_AUTO (1U << 1) | |
88ddffae VSO |
58 | |
59 | /* bits [1, 8] U [56, 63] are reserved */ | |
60 | #define BME_TABLE_ENTRY_RESERVED_MASK 0xff000000000001feULL | |
61 | #define BME_TABLE_ENTRY_OFFSET_MASK 0x00fffffffffffe00ULL | |
62 | #define BME_TABLE_ENTRY_FLAG_ALL_ONES (1ULL << 0) | |
63 | ||
64 | typedef struct QEMU_PACKED Qcow2BitmapDirEntry { | |
65 | /* header is 8 byte aligned */ | |
66 | uint64_t bitmap_table_offset; | |
67 | ||
68 | uint32_t bitmap_table_size; | |
69 | uint32_t flags; | |
70 | ||
71 | uint8_t type; | |
72 | uint8_t granularity_bits; | |
73 | uint16_t name_size; | |
74 | uint32_t extra_data_size; | |
75 | /* extra data follows */ | |
76 | /* name follows */ | |
77 | } Qcow2BitmapDirEntry; | |
78 | ||
79 | typedef struct Qcow2BitmapTable { | |
80 | uint64_t offset; | |
81 | uint32_t size; /* number of 64bit entries */ | |
82 | QSIMPLEQ_ENTRY(Qcow2BitmapTable) entry; | |
83 | } Qcow2BitmapTable; | |
84 | ||
85 | typedef struct Qcow2Bitmap { | |
86 | Qcow2BitmapTable table; | |
87 | uint32_t flags; | |
88 | uint8_t granularity_bits; | |
89 | char *name; | |
90 | ||
5f72826e VSO |
91 | BdrvDirtyBitmap *dirty_bitmap; |
92 | ||
88ddffae VSO |
93 | QSIMPLEQ_ENTRY(Qcow2Bitmap) entry; |
94 | } Qcow2Bitmap; | |
95 | typedef QSIMPLEQ_HEAD(Qcow2BitmapList, Qcow2Bitmap) Qcow2BitmapList; | |
96 | ||
97 | typedef enum BitmapType { | |
98 | BT_DIRTY_TRACKING_BITMAP = 1 | |
99 | } BitmapType; | |
100 | ||
d1258dd0 VSO |
101 | static inline bool can_write(BlockDriverState *bs) |
102 | { | |
103 | return !bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE); | |
104 | } | |
105 | ||
106 | static int update_header_sync(BlockDriverState *bs) | |
107 | { | |
108 | int ret; | |
109 | ||
110 | ret = qcow2_update_header(bs); | |
111 | if (ret < 0) { | |
112 | return ret; | |
113 | } | |
114 | ||
1a0c2bfb | 115 | return bdrv_flush(bs->file->bs); |
d1258dd0 VSO |
116 | } |
117 | ||
5f72826e VSO |
118 | static inline void bitmap_table_to_be(uint64_t *bitmap_table, size_t size) |
119 | { | |
120 | size_t i; | |
121 | ||
122 | for (i = 0; i < size; ++i) { | |
caacea4b | 123 | bitmap_table[i] = cpu_to_be64(bitmap_table[i]); |
5f72826e VSO |
124 | } |
125 | } | |
126 | ||
88ddffae VSO |
127 | static int check_table_entry(uint64_t entry, int cluster_size) |
128 | { | |
129 | uint64_t offset; | |
130 | ||
131 | if (entry & BME_TABLE_ENTRY_RESERVED_MASK) { | |
132 | return -EINVAL; | |
133 | } | |
134 | ||
135 | offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
136 | if (offset != 0) { | |
137 | /* if offset specified, bit 0 is reserved */ | |
138 | if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) { | |
139 | return -EINVAL; | |
140 | } | |
141 | ||
142 | if (offset % cluster_size != 0) { | |
143 | return -EINVAL; | |
144 | } | |
145 | } | |
146 | ||
147 | return 0; | |
148 | } | |
149 | ||
570542ec T |
150 | static int64_t get_bitmap_bytes_needed(int64_t len, uint32_t granularity) |
151 | { | |
152 | int64_t num_bits = DIV_ROUND_UP(len, granularity); | |
153 | ||
154 | return DIV_ROUND_UP(num_bits, 8); | |
155 | } | |
156 | ||
5f72826e VSO |
157 | static int check_constraints_on_bitmap(BlockDriverState *bs, |
158 | const char *name, | |
159 | uint32_t granularity, | |
160 | Error **errp) | |
161 | { | |
162 | BDRVQcow2State *s = bs->opaque; | |
163 | int granularity_bits = ctz32(granularity); | |
164 | int64_t len = bdrv_getlength(bs); | |
570542ec | 165 | int64_t bitmap_bytes; |
5f72826e VSO |
166 | |
167 | assert(granularity > 0); | |
168 | assert((granularity & (granularity - 1)) == 0); | |
169 | ||
170 | if (len < 0) { | |
171 | error_setg_errno(errp, -len, "Failed to get size of '%s'", | |
172 | bdrv_get_device_or_node_name(bs)); | |
173 | return len; | |
174 | } | |
175 | ||
176 | if (granularity_bits > BME_MAX_GRANULARITY_BITS) { | |
177 | error_setg(errp, "Granularity exceeds maximum (%llu bytes)", | |
178 | 1ULL << BME_MAX_GRANULARITY_BITS); | |
179 | return -EINVAL; | |
180 | } | |
181 | if (granularity_bits < BME_MIN_GRANULARITY_BITS) { | |
182 | error_setg(errp, "Granularity is under minimum (%llu bytes)", | |
183 | 1ULL << BME_MIN_GRANULARITY_BITS); | |
184 | return -EINVAL; | |
185 | } | |
186 | ||
570542ec T |
187 | bitmap_bytes = get_bitmap_bytes_needed(len, granularity); |
188 | if ((bitmap_bytes > (uint64_t)BME_MAX_PHYS_SIZE) || | |
189 | (bitmap_bytes > (uint64_t)BME_MAX_TABLE_SIZE * s->cluster_size)) | |
5f72826e VSO |
190 | { |
191 | error_setg(errp, "Too much space will be occupied by the bitmap. " | |
192 | "Use larger granularity"); | |
193 | return -EINVAL; | |
194 | } | |
195 | ||
196 | if (strlen(name) > BME_MAX_NAME_SIZE) { | |
197 | error_setg(errp, "Name length exceeds maximum (%u characters)", | |
198 | BME_MAX_NAME_SIZE); | |
199 | return -EINVAL; | |
200 | } | |
201 | ||
202 | return 0; | |
203 | } | |
204 | ||
205 | static void clear_bitmap_table(BlockDriverState *bs, uint64_t *bitmap_table, | |
206 | uint32_t bitmap_table_size) | |
207 | { | |
208 | BDRVQcow2State *s = bs->opaque; | |
209 | int i; | |
210 | ||
211 | for (i = 0; i < bitmap_table_size; ++i) { | |
212 | uint64_t addr = bitmap_table[i] & BME_TABLE_ENTRY_OFFSET_MASK; | |
213 | if (!addr) { | |
214 | continue; | |
215 | } | |
216 | ||
444b8236 | 217 | qcow2_free_clusters(bs, addr, s->cluster_size, QCOW2_DISCARD_ALWAYS); |
5f72826e VSO |
218 | bitmap_table[i] = 0; |
219 | } | |
220 | } | |
221 | ||
88ddffae VSO |
222 | static int bitmap_table_load(BlockDriverState *bs, Qcow2BitmapTable *tb, |
223 | uint64_t **bitmap_table) | |
224 | { | |
225 | int ret; | |
226 | BDRVQcow2State *s = bs->opaque; | |
227 | uint32_t i; | |
228 | uint64_t *table; | |
229 | ||
230 | assert(tb->size != 0); | |
231 | table = g_try_new(uint64_t, tb->size); | |
232 | if (table == NULL) { | |
233 | return -ENOMEM; | |
234 | } | |
235 | ||
236 | assert(tb->size <= BME_MAX_TABLE_SIZE); | |
237 | ret = bdrv_pread(bs->file, tb->offset, | |
02b1ecfa | 238 | table, tb->size * BME_TABLE_ENTRY_SIZE); |
88ddffae VSO |
239 | if (ret < 0) { |
240 | goto fail; | |
241 | } | |
242 | ||
243 | for (i = 0; i < tb->size; ++i) { | |
caacea4b | 244 | table[i] = be64_to_cpu(table[i]); |
88ddffae VSO |
245 | ret = check_table_entry(table[i], s->cluster_size); |
246 | if (ret < 0) { | |
247 | goto fail; | |
248 | } | |
249 | } | |
250 | ||
251 | *bitmap_table = table; | |
252 | return 0; | |
253 | ||
254 | fail: | |
255 | g_free(table); | |
256 | ||
257 | return ret; | |
258 | } | |
259 | ||
5f72826e VSO |
260 | static int free_bitmap_clusters(BlockDriverState *bs, Qcow2BitmapTable *tb) |
261 | { | |
262 | int ret; | |
263 | uint64_t *bitmap_table; | |
264 | ||
265 | ret = bitmap_table_load(bs, tb, &bitmap_table); | |
266 | if (ret < 0) { | |
5f72826e VSO |
267 | return ret; |
268 | } | |
269 | ||
270 | clear_bitmap_table(bs, bitmap_table, tb->size); | |
02b1ecfa | 271 | qcow2_free_clusters(bs, tb->offset, tb->size * BME_TABLE_ENTRY_SIZE, |
5f72826e VSO |
272 | QCOW2_DISCARD_OTHER); |
273 | g_free(bitmap_table); | |
274 | ||
275 | tb->offset = 0; | |
276 | tb->size = 0; | |
277 | ||
278 | return 0; | |
279 | } | |
280 | ||
c7e7c87a EB |
281 | /* Return the disk size covered by a single qcow2 cluster of bitmap data. */ |
282 | static uint64_t bytes_covered_by_bitmap_cluster(const BDRVQcow2State *s, | |
283 | const BdrvDirtyBitmap *bitmap) | |
d1258dd0 | 284 | { |
c7e7c87a EB |
285 | uint64_t granularity = bdrv_dirty_bitmap_granularity(bitmap); |
286 | uint64_t limit = granularity * (s->cluster_size << 3); | |
d1258dd0 | 287 | |
c7e7c87a | 288 | assert(QEMU_IS_ALIGNED(limit, |
113754f3 | 289 | bdrv_dirty_bitmap_serialization_align(bitmap))); |
c7e7c87a | 290 | return limit; |
d1258dd0 VSO |
291 | } |
292 | ||
293 | /* load_bitmap_data | |
294 | * @bitmap_table entries must satisfy specification constraints. | |
295 | * @bitmap must be cleared */ | |
296 | static int load_bitmap_data(BlockDriverState *bs, | |
297 | const uint64_t *bitmap_table, | |
298 | uint32_t bitmap_table_size, | |
299 | BdrvDirtyBitmap *bitmap) | |
300 | { | |
301 | int ret = 0; | |
302 | BDRVQcow2State *s = bs->opaque; | |
ab94db6f | 303 | uint64_t offset, limit; |
d1258dd0 VSO |
304 | uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); |
305 | uint8_t *buf = NULL; | |
306 | uint64_t i, tab_size = | |
307 | size_to_clusters(s, | |
86f6ae67 | 308 | bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size)); |
d1258dd0 VSO |
309 | |
310 | if (tab_size != bitmap_table_size || tab_size > BME_MAX_TABLE_SIZE) { | |
311 | return -EINVAL; | |
312 | } | |
313 | ||
314 | buf = g_malloc(s->cluster_size); | |
c7e7c87a | 315 | limit = bytes_covered_by_bitmap_cluster(s, bitmap); |
ab94db6f EB |
316 | for (i = 0, offset = 0; i < tab_size; ++i, offset += limit) { |
317 | uint64_t count = MIN(bm_size - offset, limit); | |
d1258dd0 | 318 | uint64_t entry = bitmap_table[i]; |
ab94db6f | 319 | uint64_t data_offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; |
d1258dd0 VSO |
320 | |
321 | assert(check_table_entry(entry, s->cluster_size) == 0); | |
322 | ||
ab94db6f | 323 | if (data_offset == 0) { |
d1258dd0 | 324 | if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) { |
ab94db6f | 325 | bdrv_dirty_bitmap_deserialize_ones(bitmap, offset, count, |
d1258dd0 VSO |
326 | false); |
327 | } else { | |
328 | /* No need to deserialize zeros because the dirty bitmap is | |
329 | * already cleared */ | |
330 | } | |
331 | } else { | |
ab94db6f | 332 | ret = bdrv_pread(bs->file, data_offset, buf, s->cluster_size); |
d1258dd0 VSO |
333 | if (ret < 0) { |
334 | goto finish; | |
335 | } | |
ab94db6f | 336 | bdrv_dirty_bitmap_deserialize_part(bitmap, buf, offset, count, |
d1258dd0 VSO |
337 | false); |
338 | } | |
339 | } | |
340 | ret = 0; | |
341 | ||
342 | bdrv_dirty_bitmap_deserialize_finish(bitmap); | |
343 | ||
344 | finish: | |
345 | g_free(buf); | |
346 | ||
347 | return ret; | |
348 | } | |
349 | ||
350 | static BdrvDirtyBitmap *load_bitmap(BlockDriverState *bs, | |
351 | Qcow2Bitmap *bm, Error **errp) | |
352 | { | |
353 | int ret; | |
354 | uint64_t *bitmap_table = NULL; | |
355 | uint32_t granularity; | |
356 | BdrvDirtyBitmap *bitmap = NULL; | |
357 | ||
74da6b94 JS |
358 | granularity = 1U << bm->granularity_bits; |
359 | bitmap = bdrv_create_dirty_bitmap(bs, granularity, bm->name, errp); | |
360 | if (bitmap == NULL) { | |
d1258dd0 VSO |
361 | goto fail; |
362 | } | |
363 | ||
74da6b94 JS |
364 | if (bm->flags & BME_FLAG_IN_USE) { |
365 | /* Data is unusable, skip loading it */ | |
366 | return bitmap; | |
367 | } | |
368 | ||
d1258dd0 VSO |
369 | ret = bitmap_table_load(bs, &bm->table, &bitmap_table); |
370 | if (ret < 0) { | |
371 | error_setg_errno(errp, -ret, | |
372 | "Could not read bitmap_table table from image for " | |
373 | "bitmap '%s'", bm->name); | |
374 | goto fail; | |
375 | } | |
376 | ||
d1258dd0 VSO |
377 | ret = load_bitmap_data(bs, bitmap_table, bm->table.size, bitmap); |
378 | if (ret < 0) { | |
379 | error_setg_errno(errp, -ret, "Could not read bitmap '%s' from image", | |
380 | bm->name); | |
381 | goto fail; | |
382 | } | |
383 | ||
384 | g_free(bitmap_table); | |
385 | return bitmap; | |
386 | ||
387 | fail: | |
388 | g_free(bitmap_table); | |
389 | if (bitmap != NULL) { | |
5deb6cbd | 390 | bdrv_release_dirty_bitmap(bitmap); |
d1258dd0 VSO |
391 | } |
392 | ||
393 | return NULL; | |
394 | } | |
395 | ||
88ddffae VSO |
396 | /* |
397 | * Bitmap List | |
398 | */ | |
399 | ||
400 | /* | |
401 | * Bitmap List private functions | |
402 | * Only Bitmap List knows about bitmap directory structure in Qcow2. | |
403 | */ | |
404 | ||
405 | static inline void bitmap_dir_entry_to_cpu(Qcow2BitmapDirEntry *entry) | |
406 | { | |
caacea4b PM |
407 | entry->bitmap_table_offset = be64_to_cpu(entry->bitmap_table_offset); |
408 | entry->bitmap_table_size = be32_to_cpu(entry->bitmap_table_size); | |
409 | entry->flags = be32_to_cpu(entry->flags); | |
410 | entry->name_size = be16_to_cpu(entry->name_size); | |
411 | entry->extra_data_size = be32_to_cpu(entry->extra_data_size); | |
88ddffae VSO |
412 | } |
413 | ||
d1258dd0 VSO |
414 | static inline void bitmap_dir_entry_to_be(Qcow2BitmapDirEntry *entry) |
415 | { | |
caacea4b PM |
416 | entry->bitmap_table_offset = cpu_to_be64(entry->bitmap_table_offset); |
417 | entry->bitmap_table_size = cpu_to_be32(entry->bitmap_table_size); | |
418 | entry->flags = cpu_to_be32(entry->flags); | |
419 | entry->name_size = cpu_to_be16(entry->name_size); | |
420 | entry->extra_data_size = cpu_to_be32(entry->extra_data_size); | |
d1258dd0 VSO |
421 | } |
422 | ||
88ddffae VSO |
423 | static inline int calc_dir_entry_size(size_t name_size, size_t extra_data_size) |
424 | { | |
9e029689 AG |
425 | int size = sizeof(Qcow2BitmapDirEntry) + name_size + extra_data_size; |
426 | return ROUND_UP(size, 8); | |
88ddffae VSO |
427 | } |
428 | ||
429 | static inline int dir_entry_size(Qcow2BitmapDirEntry *entry) | |
430 | { | |
431 | return calc_dir_entry_size(entry->name_size, entry->extra_data_size); | |
432 | } | |
433 | ||
434 | static inline const char *dir_entry_name_field(Qcow2BitmapDirEntry *entry) | |
435 | { | |
436 | return (const char *)(entry + 1) + entry->extra_data_size; | |
437 | } | |
438 | ||
439 | static inline char *dir_entry_copy_name(Qcow2BitmapDirEntry *entry) | |
440 | { | |
441 | const char *name_field = dir_entry_name_field(entry); | |
442 | return g_strndup(name_field, entry->name_size); | |
443 | } | |
444 | ||
445 | static inline Qcow2BitmapDirEntry *next_dir_entry(Qcow2BitmapDirEntry *entry) | |
446 | { | |
447 | return (Qcow2BitmapDirEntry *)((uint8_t *)entry + dir_entry_size(entry)); | |
448 | } | |
449 | ||
450 | static int check_dir_entry(BlockDriverState *bs, Qcow2BitmapDirEntry *entry) | |
451 | { | |
452 | BDRVQcow2State *s = bs->opaque; | |
453 | uint64_t phys_bitmap_bytes; | |
454 | int64_t len; | |
455 | ||
456 | bool fail = (entry->bitmap_table_size == 0) || | |
457 | (entry->bitmap_table_offset == 0) || | |
458 | (entry->bitmap_table_offset % s->cluster_size) || | |
459 | (entry->bitmap_table_size > BME_MAX_TABLE_SIZE) || | |
460 | (entry->granularity_bits > BME_MAX_GRANULARITY_BITS) || | |
461 | (entry->granularity_bits < BME_MIN_GRANULARITY_BITS) || | |
462 | (entry->flags & BME_RESERVED_FLAGS) || | |
463 | (entry->name_size > BME_MAX_NAME_SIZE) || | |
464 | (entry->type != BT_DIRTY_TRACKING_BITMAP); | |
465 | ||
466 | if (fail) { | |
467 | return -EINVAL; | |
468 | } | |
469 | ||
470 | phys_bitmap_bytes = (uint64_t)entry->bitmap_table_size * s->cluster_size; | |
471 | len = bdrv_getlength(bs); | |
472 | ||
473 | if (len < 0) { | |
474 | return len; | |
475 | } | |
476 | ||
bf5f0cf5 VSO |
477 | if (phys_bitmap_bytes > BME_MAX_PHYS_SIZE) { |
478 | return -EINVAL; | |
479 | } | |
88ddffae | 480 | |
bf5f0cf5 VSO |
481 | if (!(entry->flags & BME_FLAG_IN_USE) && |
482 | (len > ((phys_bitmap_bytes * 8) << entry->granularity_bits))) | |
483 | { | |
484 | /* | |
485 | * We've loaded a valid bitmap (IN_USE not set) or we are going to | |
486 | * store a valid bitmap, but the allocated bitmap table size is not | |
487 | * enough to store this bitmap. | |
488 | * | |
489 | * Note, that it's OK to have an invalid bitmap with invalid size due | |
490 | * to a bitmap that was not correctly saved after image resize. | |
491 | */ | |
492 | return -EINVAL; | |
493 | } | |
494 | ||
495 | return 0; | |
88ddffae VSO |
496 | } |
497 | ||
d1258dd0 VSO |
498 | static inline void bitmap_directory_to_be(uint8_t *dir, size_t size) |
499 | { | |
500 | uint8_t *end = dir + size; | |
501 | while (dir < end) { | |
502 | Qcow2BitmapDirEntry *e = (Qcow2BitmapDirEntry *)dir; | |
503 | dir += dir_entry_size(e); | |
504 | ||
505 | bitmap_dir_entry_to_be(e); | |
506 | } | |
507 | } | |
508 | ||
88ddffae VSO |
509 | /* |
510 | * Bitmap List public functions | |
511 | */ | |
512 | ||
513 | static void bitmap_free(Qcow2Bitmap *bm) | |
514 | { | |
b6b75a99 VSO |
515 | if (bm == NULL) { |
516 | return; | |
517 | } | |
518 | ||
88ddffae VSO |
519 | g_free(bm->name); |
520 | g_free(bm); | |
521 | } | |
522 | ||
523 | static void bitmap_list_free(Qcow2BitmapList *bm_list) | |
524 | { | |
525 | Qcow2Bitmap *bm; | |
526 | ||
527 | if (bm_list == NULL) { | |
528 | return; | |
529 | } | |
530 | ||
531 | while ((bm = QSIMPLEQ_FIRST(bm_list)) != NULL) { | |
532 | QSIMPLEQ_REMOVE_HEAD(bm_list, entry); | |
533 | bitmap_free(bm); | |
534 | } | |
535 | ||
536 | g_free(bm_list); | |
537 | } | |
538 | ||
539 | static Qcow2BitmapList *bitmap_list_new(void) | |
540 | { | |
541 | Qcow2BitmapList *bm_list = g_new(Qcow2BitmapList, 1); | |
542 | QSIMPLEQ_INIT(bm_list); | |
543 | ||
544 | return bm_list; | |
545 | } | |
546 | ||
d1258dd0 VSO |
547 | static uint32_t bitmap_list_count(Qcow2BitmapList *bm_list) |
548 | { | |
549 | Qcow2Bitmap *bm; | |
550 | uint32_t nb_bitmaps = 0; | |
551 | ||
552 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
553 | nb_bitmaps++; | |
554 | } | |
555 | ||
556 | return nb_bitmaps; | |
557 | } | |
558 | ||
88ddffae VSO |
559 | /* bitmap_list_load |
560 | * Get bitmap list from qcow2 image. Actually reads bitmap directory, | |
561 | * checks it and convert to bitmap list. | |
562 | */ | |
563 | static Qcow2BitmapList *bitmap_list_load(BlockDriverState *bs, uint64_t offset, | |
564 | uint64_t size, Error **errp) | |
565 | { | |
566 | int ret; | |
567 | BDRVQcow2State *s = bs->opaque; | |
568 | uint8_t *dir, *dir_end; | |
569 | Qcow2BitmapDirEntry *e; | |
570 | uint32_t nb_dir_entries = 0; | |
571 | Qcow2BitmapList *bm_list = NULL; | |
572 | ||
573 | if (size == 0) { | |
574 | error_setg(errp, "Requested bitmap directory size is zero"); | |
575 | return NULL; | |
576 | } | |
577 | ||
578 | if (size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
579 | error_setg(errp, "Requested bitmap directory size is too big"); | |
580 | return NULL; | |
581 | } | |
582 | ||
583 | dir = g_try_malloc(size); | |
584 | if (dir == NULL) { | |
585 | error_setg(errp, "Failed to allocate space for bitmap directory"); | |
586 | return NULL; | |
587 | } | |
588 | dir_end = dir + size; | |
589 | ||
590 | ret = bdrv_pread(bs->file, offset, dir, size); | |
591 | if (ret < 0) { | |
592 | error_setg_errno(errp, -ret, "Failed to read bitmap directory"); | |
593 | goto fail; | |
594 | } | |
595 | ||
596 | bm_list = bitmap_list_new(); | |
597 | for (e = (Qcow2BitmapDirEntry *)dir; | |
598 | e < (Qcow2BitmapDirEntry *)dir_end; | |
599 | e = next_dir_entry(e)) | |
600 | { | |
601 | Qcow2Bitmap *bm; | |
602 | ||
603 | if ((uint8_t *)(e + 1) > dir_end) { | |
604 | goto broken_dir; | |
605 | } | |
606 | ||
607 | if (++nb_dir_entries > s->nb_bitmaps) { | |
608 | error_setg(errp, "More bitmaps found than specified in header" | |
609 | " extension"); | |
610 | goto fail; | |
611 | } | |
612 | bitmap_dir_entry_to_cpu(e); | |
613 | ||
614 | if ((uint8_t *)next_dir_entry(e) > dir_end) { | |
615 | goto broken_dir; | |
616 | } | |
617 | ||
618 | if (e->extra_data_size != 0) { | |
619 | error_setg(errp, "Bitmap extra data is not supported"); | |
620 | goto fail; | |
621 | } | |
622 | ||
623 | ret = check_dir_entry(bs, e); | |
624 | if (ret < 0) { | |
625 | error_setg(errp, "Bitmap '%.*s' doesn't satisfy the constraints", | |
626 | e->name_size, dir_entry_name_field(e)); | |
627 | goto fail; | |
628 | } | |
629 | ||
5330f32b | 630 | bm = g_new0(Qcow2Bitmap, 1); |
88ddffae VSO |
631 | bm->table.offset = e->bitmap_table_offset; |
632 | bm->table.size = e->bitmap_table_size; | |
633 | bm->flags = e->flags; | |
634 | bm->granularity_bits = e->granularity_bits; | |
635 | bm->name = dir_entry_copy_name(e); | |
636 | QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry); | |
637 | } | |
638 | ||
639 | if (nb_dir_entries != s->nb_bitmaps) { | |
640 | error_setg(errp, "Less bitmaps found than specified in header" | |
641 | " extension"); | |
642 | goto fail; | |
643 | } | |
644 | ||
645 | if ((uint8_t *)e != dir_end) { | |
646 | goto broken_dir; | |
647 | } | |
648 | ||
649 | g_free(dir); | |
650 | return bm_list; | |
651 | ||
652 | broken_dir: | |
88ddffae VSO |
653 | error_setg(errp, "Broken bitmap directory"); |
654 | ||
655 | fail: | |
656 | g_free(dir); | |
657 | bitmap_list_free(bm_list); | |
658 | ||
659 | return NULL; | |
660 | } | |
661 | ||
662 | int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, | |
663 | void **refcount_table, | |
664 | int64_t *refcount_table_size) | |
665 | { | |
666 | int ret; | |
667 | BDRVQcow2State *s = bs->opaque; | |
668 | Qcow2BitmapList *bm_list; | |
669 | Qcow2Bitmap *bm; | |
670 | ||
671 | if (s->nb_bitmaps == 0) { | |
672 | return 0; | |
673 | } | |
674 | ||
675 | ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_size, | |
676 | s->bitmap_directory_offset, | |
677 | s->bitmap_directory_size); | |
678 | if (ret < 0) { | |
679 | return ret; | |
680 | } | |
681 | ||
682 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
683 | s->bitmap_directory_size, NULL); | |
684 | if (bm_list == NULL) { | |
685 | res->corruptions++; | |
686 | return -EINVAL; | |
687 | } | |
688 | ||
689 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
690 | uint64_t *bitmap_table = NULL; | |
691 | int i; | |
692 | ||
693 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
694 | refcount_table, refcount_table_size, | |
695 | bm->table.offset, | |
02b1ecfa | 696 | bm->table.size * BME_TABLE_ENTRY_SIZE); |
88ddffae VSO |
697 | if (ret < 0) { |
698 | goto out; | |
699 | } | |
700 | ||
701 | ret = bitmap_table_load(bs, &bm->table, &bitmap_table); | |
702 | if (ret < 0) { | |
703 | res->corruptions++; | |
704 | goto out; | |
705 | } | |
706 | ||
707 | for (i = 0; i < bm->table.size; ++i) { | |
708 | uint64_t entry = bitmap_table[i]; | |
709 | uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
710 | ||
711 | if (check_table_entry(entry, s->cluster_size) < 0) { | |
712 | res->corruptions++; | |
713 | continue; | |
714 | } | |
715 | ||
716 | if (offset == 0) { | |
717 | continue; | |
718 | } | |
719 | ||
720 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
721 | refcount_table, refcount_table_size, | |
722 | offset, s->cluster_size); | |
723 | if (ret < 0) { | |
724 | g_free(bitmap_table); | |
725 | goto out; | |
726 | } | |
727 | } | |
728 | ||
729 | g_free(bitmap_table); | |
730 | } | |
731 | ||
732 | out: | |
733 | bitmap_list_free(bm_list); | |
734 | ||
735 | return ret; | |
736 | } | |
d1258dd0 VSO |
737 | |
738 | /* bitmap_list_store | |
739 | * Store bitmap list to qcow2 image as a bitmap directory. | |
740 | * Everything is checked. | |
741 | */ | |
742 | static int bitmap_list_store(BlockDriverState *bs, Qcow2BitmapList *bm_list, | |
743 | uint64_t *offset, uint64_t *size, bool in_place) | |
744 | { | |
745 | int ret; | |
746 | uint8_t *dir; | |
747 | int64_t dir_offset = 0; | |
748 | uint64_t dir_size = 0; | |
749 | Qcow2Bitmap *bm; | |
750 | Qcow2BitmapDirEntry *e; | |
751 | ||
752 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
753 | dir_size += calc_dir_entry_size(strlen(bm->name), 0); | |
754 | } | |
755 | ||
756 | if (dir_size == 0 || dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
757 | return -EINVAL; | |
758 | } | |
759 | ||
760 | if (in_place) { | |
761 | if (*size != dir_size || *offset == 0) { | |
762 | return -EINVAL; | |
763 | } | |
764 | ||
765 | dir_offset = *offset; | |
766 | } | |
767 | ||
6388903e | 768 | dir = g_try_malloc0(dir_size); |
d1258dd0 VSO |
769 | if (dir == NULL) { |
770 | return -ENOMEM; | |
771 | } | |
772 | ||
773 | e = (Qcow2BitmapDirEntry *)dir; | |
774 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
775 | e->bitmap_table_offset = bm->table.offset; | |
776 | e->bitmap_table_size = bm->table.size; | |
777 | e->flags = bm->flags; | |
778 | e->type = BT_DIRTY_TRACKING_BITMAP; | |
779 | e->granularity_bits = bm->granularity_bits; | |
780 | e->name_size = strlen(bm->name); | |
781 | e->extra_data_size = 0; | |
782 | memcpy(e + 1, bm->name, e->name_size); | |
783 | ||
784 | if (check_dir_entry(bs, e) < 0) { | |
785 | ret = -EINVAL; | |
786 | goto fail; | |
787 | } | |
788 | ||
789 | e = next_dir_entry(e); | |
790 | } | |
791 | ||
792 | bitmap_directory_to_be(dir, dir_size); | |
793 | ||
794 | if (!in_place) { | |
795 | dir_offset = qcow2_alloc_clusters(bs, dir_size); | |
796 | if (dir_offset < 0) { | |
797 | ret = dir_offset; | |
798 | goto fail; | |
799 | } | |
800 | } | |
801 | ||
0e4e4318 VSO |
802 | /* Actually, even in in-place case ignoring QCOW2_OL_BITMAP_DIRECTORY is not |
803 | * necessary, because we drop QCOW2_AUTOCLEAR_BITMAPS when updating bitmap | |
804 | * directory in-place (actually, turn-off the extension), which is checked | |
805 | * in qcow2_check_metadata_overlap() */ | |
806 | ret = qcow2_pre_write_overlap_check( | |
966b000f KW |
807 | bs, in_place ? QCOW2_OL_BITMAP_DIRECTORY : 0, dir_offset, dir_size, |
808 | false); | |
d1258dd0 VSO |
809 | if (ret < 0) { |
810 | goto fail; | |
811 | } | |
812 | ||
813 | ret = bdrv_pwrite(bs->file, dir_offset, dir, dir_size); | |
814 | if (ret < 0) { | |
815 | goto fail; | |
816 | } | |
817 | ||
818 | g_free(dir); | |
819 | ||
820 | if (!in_place) { | |
821 | *size = dir_size; | |
822 | *offset = dir_offset; | |
823 | } | |
824 | ||
825 | return 0; | |
826 | ||
827 | fail: | |
828 | g_free(dir); | |
829 | ||
830 | if (!in_place && dir_offset > 0) { | |
831 | qcow2_free_clusters(bs, dir_offset, dir_size, QCOW2_DISCARD_OTHER); | |
832 | } | |
833 | ||
834 | return ret; | |
835 | } | |
836 | ||
837 | /* | |
838 | * Bitmap List end | |
839 | */ | |
840 | ||
841 | static int update_ext_header_and_dir_in_place(BlockDriverState *bs, | |
842 | Qcow2BitmapList *bm_list) | |
843 | { | |
844 | BDRVQcow2State *s = bs->opaque; | |
845 | int ret; | |
846 | ||
847 | if (!(s->autoclear_features & QCOW2_AUTOCLEAR_BITMAPS) || | |
848 | bm_list == NULL || QSIMPLEQ_EMPTY(bm_list) || | |
849 | bitmap_list_count(bm_list) != s->nb_bitmaps) | |
850 | { | |
851 | return -EINVAL; | |
852 | } | |
853 | ||
854 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
855 | ret = update_header_sync(bs); | |
856 | if (ret < 0) { | |
857 | /* Two variants are possible here: | |
858 | * 1. Autoclear flag is dropped, all bitmaps will be lost. | |
859 | * 2. Autoclear flag is not dropped, old state is left. | |
860 | */ | |
861 | return ret; | |
862 | } | |
863 | ||
864 | /* autoclear bit is not set, so we can safely update bitmap directory */ | |
865 | ||
866 | ret = bitmap_list_store(bs, bm_list, &s->bitmap_directory_offset, | |
867 | &s->bitmap_directory_size, true); | |
868 | if (ret < 0) { | |
869 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
870 | * qemu-img check */ | |
871 | return ret; | |
872 | } | |
873 | ||
874 | ret = update_header_sync(bs); | |
875 | if (ret < 0) { | |
876 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
877 | * qemu-img check */ | |
878 | return ret; | |
879 | } | |
880 | ||
881 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
882 | return update_header_sync(bs); | |
883 | /* If final update_header_sync() fails, two variants are possible: | |
884 | * 1. Autoclear flag is not set, all bitmaps will be lost. | |
885 | * 2. Autoclear flag is set, header and directory are successfully updated. | |
886 | */ | |
887 | } | |
888 | ||
5f72826e VSO |
889 | static int update_ext_header_and_dir(BlockDriverState *bs, |
890 | Qcow2BitmapList *bm_list) | |
891 | { | |
892 | BDRVQcow2State *s = bs->opaque; | |
893 | int ret; | |
894 | uint64_t new_offset = 0; | |
895 | uint64_t new_size = 0; | |
896 | uint32_t new_nb_bitmaps = 0; | |
897 | uint64_t old_offset = s->bitmap_directory_offset; | |
898 | uint64_t old_size = s->bitmap_directory_size; | |
899 | uint32_t old_nb_bitmaps = s->nb_bitmaps; | |
900 | uint64_t old_autocl = s->autoclear_features; | |
901 | ||
902 | if (bm_list != NULL && !QSIMPLEQ_EMPTY(bm_list)) { | |
903 | new_nb_bitmaps = bitmap_list_count(bm_list); | |
904 | ||
905 | if (new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
906 | return -EINVAL; | |
907 | } | |
908 | ||
909 | ret = bitmap_list_store(bs, bm_list, &new_offset, &new_size, false); | |
910 | if (ret < 0) { | |
911 | return ret; | |
912 | } | |
913 | ||
1a0c2bfb | 914 | ret = qcow2_flush_caches(bs); |
5f72826e VSO |
915 | if (ret < 0) { |
916 | goto fail; | |
917 | } | |
918 | ||
919 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
920 | } else { | |
921 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
922 | } | |
923 | ||
924 | s->bitmap_directory_offset = new_offset; | |
925 | s->bitmap_directory_size = new_size; | |
926 | s->nb_bitmaps = new_nb_bitmaps; | |
927 | ||
928 | ret = update_header_sync(bs); | |
929 | if (ret < 0) { | |
930 | goto fail; | |
931 | } | |
932 | ||
933 | if (old_size > 0) { | |
934 | qcow2_free_clusters(bs, old_offset, old_size, QCOW2_DISCARD_OTHER); | |
935 | } | |
936 | ||
937 | return 0; | |
938 | ||
939 | fail: | |
940 | if (new_offset > 0) { | |
941 | qcow2_free_clusters(bs, new_offset, new_size, QCOW2_DISCARD_OTHER); | |
942 | } | |
943 | ||
944 | s->bitmap_directory_offset = old_offset; | |
945 | s->bitmap_directory_size = old_size; | |
946 | s->nb_bitmaps = old_nb_bitmaps; | |
947 | s->autoclear_features = old_autocl; | |
948 | ||
949 | return ret; | |
950 | } | |
951 | ||
d1258dd0 VSO |
952 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ |
953 | static void release_dirty_bitmap_helper(gpointer bitmap, | |
954 | gpointer bs) | |
955 | { | |
5deb6cbd | 956 | bdrv_release_dirty_bitmap(bitmap); |
d1258dd0 VSO |
957 | } |
958 | ||
959 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ | |
960 | static void set_readonly_helper(gpointer bitmap, gpointer value) | |
961 | { | |
962 | bdrv_dirty_bitmap_set_readonly(bitmap, (bool)value); | |
963 | } | |
964 | ||
3e99da5e | 965 | /* qcow2_load_dirty_bitmaps() |
d1258dd0 VSO |
966 | * Return value is a hint for caller: true means that the Qcow2 header was |
967 | * updated. (false doesn't mean that the header should be updated by the | |
968 | * caller, it just means that updating was not needed or the image cannot be | |
969 | * written to). | |
970 | * On failure the function returns false. | |
971 | */ | |
3e99da5e | 972 | bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) |
d1258dd0 VSO |
973 | { |
974 | BDRVQcow2State *s = bs->opaque; | |
975 | Qcow2BitmapList *bm_list; | |
976 | Qcow2Bitmap *bm; | |
977 | GSList *created_dirty_bitmaps = NULL; | |
978 | bool header_updated = false; | |
74da6b94 | 979 | bool needs_update = false; |
d1258dd0 VSO |
980 | |
981 | if (s->nb_bitmaps == 0) { | |
982 | /* No bitmaps - nothing to do */ | |
983 | return false; | |
984 | } | |
985 | ||
986 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
987 | s->bitmap_directory_size, errp); | |
988 | if (bm_list == NULL) { | |
989 | return false; | |
990 | } | |
991 | ||
992 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
a505475b VSO |
993 | BdrvDirtyBitmap *bitmap; |
994 | ||
995 | if ((bm->flags & BME_FLAG_IN_USE) && | |
996 | bdrv_find_dirty_bitmap(bs, bm->name)) | |
997 | { | |
998 | /* | |
999 | * We already have corresponding BdrvDirtyBitmap, and bitmap in the | |
1000 | * image is marked IN_USE. Firstly, this state is valid, no reason | |
1001 | * to consider existing BdrvDirtyBitmap to be bad. Secondly it's | |
1002 | * absolutely possible, when we do migration with shared storage | |
1003 | * with dirty-bitmaps capability enabled: if the bitmap was loaded | |
1004 | * from this storage before migration start, the storage will | |
1005 | * of-course contain IN_USE outdated version of the bitmap, and we | |
1006 | * should not load it on migration target, as we already have this | |
1007 | * bitmap, being migrated. | |
1008 | */ | |
1009 | continue; | |
1010 | } | |
1011 | ||
1012 | bitmap = load_bitmap(bs, bm, errp); | |
74da6b94 JS |
1013 | if (bitmap == NULL) { |
1014 | goto fail; | |
1015 | } | |
a0319aac | 1016 | |
796a3798 | 1017 | bdrv_dirty_bitmap_set_persistence(bitmap, true); |
74da6b94 JS |
1018 | if (bm->flags & BME_FLAG_IN_USE) { |
1019 | bdrv_dirty_bitmap_set_inconsistent(bitmap); | |
1020 | } else { | |
1021 | /* NB: updated flags only get written if can_write(bs) is true. */ | |
d1258dd0 | 1022 | bm->flags |= BME_FLAG_IN_USE; |
74da6b94 | 1023 | needs_update = true; |
d1258dd0 | 1024 | } |
74da6b94 JS |
1025 | if (!(bm->flags & BME_FLAG_AUTO)) { |
1026 | bdrv_disable_dirty_bitmap(bitmap); | |
1027 | } | |
1028 | created_dirty_bitmaps = | |
1029 | g_slist_append(created_dirty_bitmaps, bitmap); | |
d1258dd0 VSO |
1030 | } |
1031 | ||
74da6b94 JS |
1032 | if (needs_update && can_write(bs)) { |
1033 | /* in_use flags must be updated */ | |
1034 | int ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
1035 | if (ret < 0) { | |
1036 | error_setg_errno(errp, -ret, "Can't update bitmap directory"); | |
1037 | goto fail; | |
d1258dd0 | 1038 | } |
74da6b94 JS |
1039 | header_updated = true; |
1040 | } | |
1041 | ||
1042 | if (!can_write(bs)) { | |
1043 | g_slist_foreach(created_dirty_bitmaps, set_readonly_helper, | |
1044 | (gpointer)true); | |
d1258dd0 VSO |
1045 | } |
1046 | ||
1047 | g_slist_free(created_dirty_bitmaps); | |
1048 | bitmap_list_free(bm_list); | |
1049 | ||
1050 | return header_updated; | |
1051 | ||
1052 | fail: | |
1053 | g_slist_foreach(created_dirty_bitmaps, release_dirty_bitmap_helper, bs); | |
1054 | g_slist_free(created_dirty_bitmaps); | |
1055 | bitmap_list_free(bm_list); | |
1056 | ||
1057 | return false; | |
1058 | } | |
1b6b0562 | 1059 | |
b8968c87 AS |
1060 | |
1061 | static Qcow2BitmapInfoFlagsList *get_bitmap_info_flags(uint32_t flags) | |
1062 | { | |
1063 | Qcow2BitmapInfoFlagsList *list = NULL; | |
1064 | Qcow2BitmapInfoFlagsList **plist = &list; | |
1065 | int i; | |
1066 | ||
1067 | static const struct { | |
1068 | int bme; /* Bitmap directory entry flags */ | |
1069 | int info; /* The flags to report to the user */ | |
1070 | } map[] = { | |
1071 | { BME_FLAG_IN_USE, QCOW2_BITMAP_INFO_FLAGS_IN_USE }, | |
1072 | { BME_FLAG_AUTO, QCOW2_BITMAP_INFO_FLAGS_AUTO }, | |
1073 | }; | |
1074 | ||
1075 | int map_size = ARRAY_SIZE(map); | |
1076 | ||
1077 | for (i = 0; i < map_size; ++i) { | |
1078 | if (flags & map[i].bme) { | |
1079 | Qcow2BitmapInfoFlagsList *entry = | |
1080 | g_new0(Qcow2BitmapInfoFlagsList, 1); | |
1081 | entry->value = map[i].info; | |
1082 | *plist = entry; | |
1083 | plist = &entry->next; | |
1084 | flags &= ~map[i].bme; | |
1085 | } | |
1086 | } | |
1087 | /* Check if the BME_* mapping above is complete */ | |
1088 | assert(!flags); | |
1089 | ||
1090 | return list; | |
1091 | } | |
1092 | ||
1093 | /* | |
1094 | * qcow2_get_bitmap_info_list() | |
1095 | * Returns a list of QCOW2 bitmap details. | |
1096 | * In case of no bitmaps, the function returns NULL and | |
1097 | * the @errp parameter is not set. | |
1098 | * When bitmap information can not be obtained, the function returns | |
1099 | * NULL and the @errp parameter is set. | |
1100 | */ | |
1101 | Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs, | |
1102 | Error **errp) | |
1103 | { | |
1104 | BDRVQcow2State *s = bs->opaque; | |
1105 | Qcow2BitmapList *bm_list; | |
1106 | Qcow2Bitmap *bm; | |
1107 | Qcow2BitmapInfoList *list = NULL; | |
1108 | Qcow2BitmapInfoList **plist = &list; | |
1109 | ||
1110 | if (s->nb_bitmaps == 0) { | |
1111 | return NULL; | |
1112 | } | |
1113 | ||
1114 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1115 | s->bitmap_directory_size, errp); | |
1116 | if (bm_list == NULL) { | |
1117 | return NULL; | |
1118 | } | |
1119 | ||
1120 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1121 | Qcow2BitmapInfo *info = g_new0(Qcow2BitmapInfo, 1); | |
1122 | Qcow2BitmapInfoList *obj = g_new0(Qcow2BitmapInfoList, 1); | |
1123 | info->granularity = 1U << bm->granularity_bits; | |
1124 | info->name = g_strdup(bm->name); | |
1125 | info->flags = get_bitmap_info_flags(bm->flags & ~BME_RESERVED_FLAGS); | |
1126 | obj->value = info; | |
1127 | *plist = obj; | |
1128 | plist = &obj->next; | |
1129 | } | |
1130 | ||
1131 | bitmap_list_free(bm_list); | |
1132 | ||
1133 | return list; | |
1134 | } | |
1135 | ||
bd429a88 | 1136 | int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp) |
1b6b0562 VSO |
1137 | { |
1138 | BDRVQcow2State *s = bs->opaque; | |
1139 | Qcow2BitmapList *bm_list; | |
1140 | Qcow2Bitmap *bm; | |
1141 | GSList *ro_dirty_bitmaps = NULL; | |
f6333cbf VSO |
1142 | int ret = -EINVAL; |
1143 | bool need_header_update = false; | |
1b6b0562 VSO |
1144 | |
1145 | if (s->nb_bitmaps == 0) { | |
1146 | /* No bitmaps - nothing to do */ | |
1147 | return 0; | |
1148 | } | |
1149 | ||
1b6b0562 VSO |
1150 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, |
1151 | s->bitmap_directory_size, errp); | |
1152 | if (bm_list == NULL) { | |
1153 | return -EINVAL; | |
1154 | } | |
1155 | ||
1156 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
74da6b94 | 1157 | BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name); |
1b6b0562 | 1158 | |
f6333cbf VSO |
1159 | if (!bitmap) { |
1160 | error_setg(errp, "Unexpected bitmap '%s' in image '%s'", | |
1161 | bm->name, bs->filename); | |
74da6b94 | 1162 | goto out; |
1b6b0562 | 1163 | } |
74da6b94 | 1164 | |
f6333cbf VSO |
1165 | if (!(bm->flags & BME_FLAG_IN_USE)) { |
1166 | if (!bdrv_dirty_bitmap_readonly(bitmap)) { | |
1167 | error_setg(errp, "Corruption: bitmap '%s' is not marked IN_USE " | |
1168 | "in the image '%s' and not marked readonly in RAM", | |
1169 | bm->name, bs->filename); | |
1170 | goto out; | |
1171 | } | |
1172 | if (bdrv_dirty_bitmap_inconsistent(bitmap)) { | |
1173 | error_setg(errp, "Corruption: bitmap '%s' is inconsistent but " | |
1174 | "is not marked IN_USE in the image '%s'", bm->name, | |
1175 | bs->filename); | |
1176 | goto out; | |
1177 | } | |
1178 | ||
1179 | bm->flags |= BME_FLAG_IN_USE; | |
1180 | need_header_update = true; | |
1181 | } else { | |
1182 | /* | |
1183 | * What if flags already has BME_FLAG_IN_USE ? | |
1184 | * | |
1185 | * 1. if we are reopening RW -> RW it's OK, of course. | |
1186 | * 2. if we are reopening RO -> RW: | |
1187 | * 2.1 if @bitmap is inconsistent, it's OK. It means that it was | |
1188 | * inconsistent (IN_USE) when we loaded it | |
1189 | * 2.2 if @bitmap is not inconsistent. This seems to be impossible | |
1190 | * and implies third party interaction. Let's error-out for | |
1191 | * safety. | |
1192 | */ | |
1193 | if (bdrv_dirty_bitmap_readonly(bitmap) && | |
1194 | !bdrv_dirty_bitmap_inconsistent(bitmap)) | |
1195 | { | |
1196 | error_setg(errp, "Corruption: bitmap '%s' is marked IN_USE " | |
1197 | "in the image '%s' but it is readonly and " | |
1198 | "consistent in RAM", | |
1199 | bm->name, bs->filename); | |
1200 | goto out; | |
1201 | } | |
1202 | } | |
1203 | ||
1204 | if (bdrv_dirty_bitmap_readonly(bitmap)) { | |
1205 | ro_dirty_bitmaps = g_slist_append(ro_dirty_bitmaps, bitmap); | |
1206 | } | |
1b6b0562 VSO |
1207 | } |
1208 | ||
f6333cbf VSO |
1209 | if (need_header_update) { |
1210 | if (!can_write(bs->file->bs) || !(bs->file->perm & BLK_PERM_WRITE)) { | |
1211 | error_setg(errp, "Failed to reopen bitmaps rw: no write access " | |
1212 | "the protocol file"); | |
1213 | goto out; | |
1214 | } | |
1215 | ||
1b6b0562 VSO |
1216 | /* in_use flags must be updated */ |
1217 | ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
1218 | if (ret < 0) { | |
f6333cbf | 1219 | error_setg_errno(errp, -ret, "Cannot update bitmap directory"); |
1b6b0562 VSO |
1220 | goto out; |
1221 | } | |
1b6b0562 VSO |
1222 | } |
1223 | ||
f6333cbf VSO |
1224 | g_slist_foreach(ro_dirty_bitmaps, set_readonly_helper, false); |
1225 | ret = 0; | |
1226 | ||
1b6b0562 VSO |
1227 | out: |
1228 | g_slist_free(ro_dirty_bitmaps); | |
1229 | bitmap_list_free(bm_list); | |
1230 | ||
1231 | return ret; | |
1232 | } | |
5f72826e | 1233 | |
d19c6b36 JS |
1234 | /* Checks to see if it's safe to resize bitmaps */ |
1235 | int qcow2_truncate_bitmaps_check(BlockDriverState *bs, Error **errp) | |
1236 | { | |
1237 | BDRVQcow2State *s = bs->opaque; | |
1238 | Qcow2BitmapList *bm_list; | |
1239 | Qcow2Bitmap *bm; | |
1240 | int ret = 0; | |
1241 | ||
1242 | if (s->nb_bitmaps == 0) { | |
1243 | return 0; | |
1244 | } | |
1245 | ||
1246 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1247 | s->bitmap_directory_size, errp); | |
1248 | if (bm_list == NULL) { | |
1249 | return -EINVAL; | |
1250 | } | |
1251 | ||
1252 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1253 | BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name); | |
1254 | if (bitmap == NULL) { | |
1255 | /* | |
1256 | * We rely on all bitmaps being in-memory to be able to resize them, | |
1257 | * Otherwise, we'd need to resize them on disk explicitly | |
1258 | */ | |
1259 | error_setg(errp, "Cannot resize qcow2 with persistent bitmaps that " | |
1260 | "were not loaded into memory"); | |
1261 | ret = -ENOTSUP; | |
1262 | goto out; | |
1263 | } | |
1264 | ||
1265 | /* | |
1266 | * The checks against readonly and busy are redundant, but certainly | |
1267 | * do no harm. checks against inconsistent are crucial: | |
1268 | */ | |
1269 | if (bdrv_dirty_bitmap_check(bitmap, BDRV_BITMAP_DEFAULT, errp)) { | |
1270 | ret = -ENOTSUP; | |
1271 | goto out; | |
1272 | } | |
1273 | } | |
1274 | ||
1275 | out: | |
1276 | bitmap_list_free(bm_list); | |
1277 | return ret; | |
1278 | } | |
1279 | ||
5f72826e VSO |
1280 | /* store_bitmap_data() |
1281 | * Store bitmap to image, filling bitmap table accordingly. | |
1282 | */ | |
1283 | static uint64_t *store_bitmap_data(BlockDriverState *bs, | |
1284 | BdrvDirtyBitmap *bitmap, | |
1285 | uint32_t *bitmap_table_size, Error **errp) | |
1286 | { | |
1287 | int ret; | |
1288 | BDRVQcow2State *s = bs->opaque; | |
49d741b5 EB |
1289 | int64_t offset; |
1290 | uint64_t limit; | |
5f72826e VSO |
1291 | uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); |
1292 | const char *bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1293 | uint8_t *buf = NULL; | |
5f72826e VSO |
1294 | uint64_t *tb; |
1295 | uint64_t tb_size = | |
1296 | size_to_clusters(s, | |
86f6ae67 | 1297 | bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size)); |
5f72826e VSO |
1298 | |
1299 | if (tb_size > BME_MAX_TABLE_SIZE || | |
1300 | tb_size * s->cluster_size > BME_MAX_PHYS_SIZE) | |
1301 | { | |
1302 | error_setg(errp, "Bitmap '%s' is too big", bm_name); | |
1303 | return NULL; | |
1304 | } | |
1305 | ||
1306 | tb = g_try_new0(uint64_t, tb_size); | |
1307 | if (tb == NULL) { | |
1308 | error_setg(errp, "No memory"); | |
1309 | return NULL; | |
1310 | } | |
1311 | ||
5f72826e | 1312 | buf = g_malloc(s->cluster_size); |
c7e7c87a | 1313 | limit = bytes_covered_by_bitmap_cluster(s, bitmap); |
c7e7c87a | 1314 | assert(DIV_ROUND_UP(bm_size, limit) == tb_size); |
5f72826e | 1315 | |
2d00cbd8 VSO |
1316 | offset = 0; |
1317 | while ((offset = bdrv_dirty_bitmap_next_dirty(bitmap, offset, INT64_MAX)) | |
1318 | >= 0) | |
1319 | { | |
49d741b5 | 1320 | uint64_t cluster = offset / limit; |
5f72826e VSO |
1321 | uint64_t end, write_size; |
1322 | int64_t off; | |
1323 | ||
49d741b5 EB |
1324 | /* |
1325 | * We found the first dirty offset, but want to write out the | |
1326 | * entire cluster of the bitmap that includes that offset, | |
1327 | * including any leading zero bits. | |
1328 | */ | |
1329 | offset = QEMU_ALIGN_DOWN(offset, limit); | |
1330 | end = MIN(bm_size, offset + limit); | |
1331 | write_size = bdrv_dirty_bitmap_serialization_size(bitmap, offset, | |
1332 | end - offset); | |
5f72826e VSO |
1333 | assert(write_size <= s->cluster_size); |
1334 | ||
1335 | off = qcow2_alloc_clusters(bs, s->cluster_size); | |
1336 | if (off < 0) { | |
1337 | error_setg_errno(errp, -off, | |
1338 | "Failed to allocate clusters for bitmap '%s'", | |
1339 | bm_name); | |
1340 | goto fail; | |
1341 | } | |
1342 | tb[cluster] = off; | |
1343 | ||
49d741b5 | 1344 | bdrv_dirty_bitmap_serialize_part(bitmap, buf, offset, end - offset); |
5f72826e VSO |
1345 | if (write_size < s->cluster_size) { |
1346 | memset(buf + write_size, 0, s->cluster_size - write_size); | |
1347 | } | |
1348 | ||
966b000f | 1349 | ret = qcow2_pre_write_overlap_check(bs, 0, off, s->cluster_size, false); |
5f72826e VSO |
1350 | if (ret < 0) { |
1351 | error_setg_errno(errp, -ret, "Qcow2 overlap check failed"); | |
1352 | goto fail; | |
1353 | } | |
1354 | ||
1355 | ret = bdrv_pwrite(bs->file, off, buf, s->cluster_size); | |
1356 | if (ret < 0) { | |
1357 | error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file", | |
1358 | bm_name); | |
1359 | goto fail; | |
1360 | } | |
1361 | ||
2d00cbd8 | 1362 | offset = end; |
5f72826e VSO |
1363 | } |
1364 | ||
1365 | *bitmap_table_size = tb_size; | |
1366 | g_free(buf); | |
5f72826e VSO |
1367 | |
1368 | return tb; | |
1369 | ||
1370 | fail: | |
1371 | clear_bitmap_table(bs, tb, tb_size); | |
1372 | g_free(buf); | |
5f72826e VSO |
1373 | g_free(tb); |
1374 | ||
1375 | return NULL; | |
1376 | } | |
1377 | ||
1378 | /* store_bitmap() | |
1379 | * Store bm->dirty_bitmap to qcow2. | |
1380 | * Set bm->table_offset and bm->table_size accordingly. | |
1381 | */ | |
1382 | static int store_bitmap(BlockDriverState *bs, Qcow2Bitmap *bm, Error **errp) | |
1383 | { | |
1384 | int ret; | |
1385 | uint64_t *tb; | |
1386 | int64_t tb_offset; | |
1387 | uint32_t tb_size; | |
1388 | BdrvDirtyBitmap *bitmap = bm->dirty_bitmap; | |
1389 | const char *bm_name; | |
1390 | ||
1391 | assert(bitmap != NULL); | |
1392 | ||
1393 | bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1394 | ||
1395 | tb = store_bitmap_data(bs, bitmap, &tb_size, errp); | |
1396 | if (tb == NULL) { | |
1397 | return -EINVAL; | |
1398 | } | |
1399 | ||
1400 | assert(tb_size <= BME_MAX_TABLE_SIZE); | |
1401 | tb_offset = qcow2_alloc_clusters(bs, tb_size * sizeof(tb[0])); | |
1402 | if (tb_offset < 0) { | |
1403 | error_setg_errno(errp, -tb_offset, | |
1404 | "Failed to allocate clusters for bitmap '%s'", | |
1405 | bm_name); | |
1406 | ret = tb_offset; | |
1407 | goto fail; | |
1408 | } | |
1409 | ||
1410 | ret = qcow2_pre_write_overlap_check(bs, 0, tb_offset, | |
966b000f | 1411 | tb_size * sizeof(tb[0]), false); |
5f72826e VSO |
1412 | if (ret < 0) { |
1413 | error_setg_errno(errp, -ret, "Qcow2 overlap check failed"); | |
1414 | goto fail; | |
1415 | } | |
1416 | ||
1417 | bitmap_table_to_be(tb, tb_size); | |
1418 | ret = bdrv_pwrite(bs->file, tb_offset, tb, tb_size * sizeof(tb[0])); | |
1419 | if (ret < 0) { | |
1420 | error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file", | |
1421 | bm_name); | |
1422 | goto fail; | |
1423 | } | |
1424 | ||
1425 | g_free(tb); | |
1426 | ||
1427 | bm->table.offset = tb_offset; | |
1428 | bm->table.size = tb_size; | |
1429 | ||
1430 | return 0; | |
1431 | ||
1432 | fail: | |
1433 | clear_bitmap_table(bs, tb, tb_size); | |
1434 | ||
1435 | if (tb_offset > 0) { | |
1436 | qcow2_free_clusters(bs, tb_offset, tb_size * sizeof(tb[0]), | |
1437 | QCOW2_DISCARD_OTHER); | |
1438 | } | |
1439 | ||
1440 | g_free(tb); | |
1441 | ||
1442 | return ret; | |
1443 | } | |
1444 | ||
1445 | static Qcow2Bitmap *find_bitmap_by_name(Qcow2BitmapList *bm_list, | |
1446 | const char *name) | |
1447 | { | |
1448 | Qcow2Bitmap *bm; | |
1449 | ||
1450 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1451 | if (strcmp(name, bm->name) == 0) { | |
1452 | return bm; | |
1453 | } | |
1454 | } | |
1455 | ||
1456 | return NULL; | |
1457 | } | |
1458 | ||
d2c3080e VSO |
1459 | int coroutine_fn qcow2_co_remove_persistent_dirty_bitmap(BlockDriverState *bs, |
1460 | const char *name, | |
1461 | Error **errp) | |
469c71ed VSO |
1462 | { |
1463 | int ret; | |
1464 | BDRVQcow2State *s = bs->opaque; | |
d2c3080e | 1465 | Qcow2Bitmap *bm = NULL; |
469c71ed VSO |
1466 | Qcow2BitmapList *bm_list; |
1467 | ||
1468 | if (s->nb_bitmaps == 0) { | |
f56281ab VSO |
1469 | /* |
1470 | * Absence of the bitmap is not an error: see explanation above | |
1471 | * bdrv_co_remove_persistent_dirty_bitmap() definition. | |
1472 | */ | |
b56a1e31 | 1473 | return 0; |
469c71ed VSO |
1474 | } |
1475 | ||
d2c3080e VSO |
1476 | qemu_co_mutex_lock(&s->lock); |
1477 | ||
469c71ed VSO |
1478 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, |
1479 | s->bitmap_directory_size, errp); | |
1480 | if (bm_list == NULL) { | |
d2c3080e VSO |
1481 | ret = -EIO; |
1482 | goto out; | |
469c71ed VSO |
1483 | } |
1484 | ||
1485 | bm = find_bitmap_by_name(bm_list, name); | |
1486 | if (bm == NULL) { | |
f56281ab VSO |
1487 | /* Absence of the bitmap is not an error, see above. */ |
1488 | ret = 0; | |
b56a1e31 | 1489 | goto out; |
469c71ed VSO |
1490 | } |
1491 | ||
1492 | QSIMPLEQ_REMOVE(bm_list, bm, Qcow2Bitmap, entry); | |
1493 | ||
1494 | ret = update_ext_header_and_dir(bs, bm_list); | |
1495 | if (ret < 0) { | |
1496 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
b56a1e31 | 1497 | goto out; |
469c71ed VSO |
1498 | } |
1499 | ||
1500 | free_bitmap_clusters(bs, &bm->table); | |
1501 | ||
b56a1e31 | 1502 | out: |
d2c3080e VSO |
1503 | qemu_co_mutex_unlock(&s->lock); |
1504 | ||
469c71ed VSO |
1505 | bitmap_free(bm); |
1506 | bitmap_list_free(bm_list); | |
b56a1e31 VSO |
1507 | |
1508 | return ret; | |
469c71ed VSO |
1509 | } |
1510 | ||
644ddbb7 VSO |
1511 | /* |
1512 | * qcow2_store_persistent_dirty_bitmaps | |
1513 | * | |
1514 | * Stores persistent BdrvDirtyBitmap objects. | |
1515 | * | |
1516 | * @release_stored: if true, release BdrvDirtyBitmap's after storing to the | |
1517 | * image. This is used in two cases, both via qcow2_inactivate: | |
1518 | * 1. bdrv_close: It's correct to remove bitmaps on close. | |
1519 | * 2. migration: If bitmaps are migrated through migration channel via | |
1520 | * 'dirty-bitmaps' migration capability they are not handled by this code. | |
1521 | * Otherwise, it's OK to drop BdrvDirtyBitmap's and reload them on | |
1522 | * invalidation. | |
1523 | * | |
1524 | * Anyway, it's correct to remove BdrvDirtyBitmap's on inactivation, as | |
1525 | * inactivation means that we lose control on disk, and therefore on bitmaps, | |
1526 | * we should sync them and do not touch more. | |
1527 | * | |
1528 | * Contrariwise, we don't want to release any bitmaps on just reopen-to-ro, | |
1529 | * when we need to store them, as image is still under our control, and it's | |
1530 | * good to keep all the bitmaps in read-only mode. Moreover, keeping them | |
1531 | * read-only is correct because this is what would happen if we opened the node | |
1532 | * readonly to begin with, and whether we opened directly or reopened to that | |
1533 | * state shouldn't matter for the state we get afterward. | |
1534 | */ | |
1535 | void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, | |
1536 | bool release_stored, Error **errp) | |
5f72826e VSO |
1537 | { |
1538 | BdrvDirtyBitmap *bitmap; | |
1539 | BDRVQcow2State *s = bs->opaque; | |
1540 | uint32_t new_nb_bitmaps = s->nb_bitmaps; | |
1541 | uint64_t new_dir_size = s->bitmap_directory_size; | |
1542 | int ret; | |
1543 | Qcow2BitmapList *bm_list; | |
1544 | Qcow2Bitmap *bm; | |
b58deb34 | 1545 | QSIMPLEQ_HEAD(, Qcow2BitmapTable) drop_tables; |
5f72826e | 1546 | Qcow2BitmapTable *tb, *tb_next; |
f88676c1 | 1547 | bool need_write = false; |
5f72826e VSO |
1548 | |
1549 | QSIMPLEQ_INIT(&drop_tables); | |
1550 | ||
1551 | if (s->nb_bitmaps == 0) { | |
1552 | bm_list = bitmap_list_new(); | |
1553 | } else { | |
1554 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1555 | s->bitmap_directory_size, errp); | |
1556 | if (bm_list == NULL) { | |
1557 | return; | |
1558 | } | |
1559 | } | |
1560 | ||
1561 | /* check constraints and names */ | |
ef9041a7 | 1562 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
5f72826e VSO |
1563 | const char *name = bdrv_dirty_bitmap_name(bitmap); |
1564 | uint32_t granularity = bdrv_dirty_bitmap_granularity(bitmap); | |
1565 | Qcow2Bitmap *bm; | |
1566 | ||
796a3798 | 1567 | if (!bdrv_dirty_bitmap_get_persistence(bitmap) || |
74da6b94 | 1568 | bdrv_dirty_bitmap_inconsistent(bitmap)) { |
5f72826e VSO |
1569 | continue; |
1570 | } | |
1571 | ||
fe16c7dd HR |
1572 | if (bdrv_dirty_bitmap_readonly(bitmap)) { |
1573 | /* | |
1574 | * Store the bitmap in the associated Qcow2Bitmap so it | |
1575 | * can be released later | |
1576 | */ | |
1577 | bm = find_bitmap_by_name(bm_list, name); | |
1578 | if (bm) { | |
1579 | bm->dirty_bitmap = bitmap; | |
1580 | } | |
1581 | continue; | |
1582 | } | |
1583 | ||
f88676c1 VSO |
1584 | need_write = true; |
1585 | ||
5f72826e VSO |
1586 | if (check_constraints_on_bitmap(bs, name, granularity, errp) < 0) { |
1587 | error_prepend(errp, "Bitmap '%s' doesn't satisfy the constraints: ", | |
1588 | name); | |
1589 | goto fail; | |
1590 | } | |
1591 | ||
1592 | bm = find_bitmap_by_name(bm_list, name); | |
1593 | if (bm == NULL) { | |
1594 | if (++new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
1595 | error_setg(errp, "Too many persistent bitmaps"); | |
1596 | goto fail; | |
1597 | } | |
1598 | ||
1599 | new_dir_size += calc_dir_entry_size(strlen(name), 0); | |
1600 | if (new_dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
1601 | error_setg(errp, "Bitmap directory is too large"); | |
1602 | goto fail; | |
1603 | } | |
1604 | ||
1605 | bm = g_new0(Qcow2Bitmap, 1); | |
1606 | bm->name = g_strdup(name); | |
1607 | QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry); | |
1608 | } else { | |
1609 | if (!(bm->flags & BME_FLAG_IN_USE)) { | |
1610 | error_setg(errp, "Bitmap '%s' already exists in the image", | |
1611 | name); | |
1612 | goto fail; | |
1613 | } | |
1614 | tb = g_memdup(&bm->table, sizeof(bm->table)); | |
1615 | bm->table.offset = 0; | |
1616 | bm->table.size = 0; | |
1617 | QSIMPLEQ_INSERT_TAIL(&drop_tables, tb, entry); | |
1618 | } | |
3e99da5e | 1619 | bm->flags = bdrv_dirty_bitmap_enabled(bitmap) ? BME_FLAG_AUTO : 0; |
5f72826e VSO |
1620 | bm->granularity_bits = ctz32(bdrv_dirty_bitmap_granularity(bitmap)); |
1621 | bm->dirty_bitmap = bitmap; | |
1622 | } | |
1623 | ||
f88676c1 VSO |
1624 | if (!need_write) { |
1625 | goto success; | |
1626 | } | |
1627 | ||
1628 | if (!can_write(bs)) { | |
1629 | error_setg(errp, "No write access"); | |
1630 | goto fail; | |
1631 | } | |
1632 | ||
5f72826e VSO |
1633 | /* allocate clusters and store bitmaps */ |
1634 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
fe16c7dd HR |
1635 | BdrvDirtyBitmap *bitmap = bm->dirty_bitmap; |
1636 | ||
1637 | if (bitmap == NULL || bdrv_dirty_bitmap_readonly(bitmap)) { | |
5f72826e VSO |
1638 | continue; |
1639 | } | |
1640 | ||
1641 | ret = store_bitmap(bs, bm, errp); | |
1642 | if (ret < 0) { | |
1643 | goto fail; | |
1644 | } | |
1645 | } | |
1646 | ||
1647 | ret = update_ext_header_and_dir(bs, bm_list); | |
1648 | if (ret < 0) { | |
1649 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
1650 | goto fail; | |
1651 | } | |
1652 | ||
1653 | /* Bitmap directory was successfully updated, so, old data can be dropped. | |
1654 | * TODO it is better to reuse these clusters */ | |
1655 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1656 | free_bitmap_clusters(bs, tb); | |
1657 | g_free(tb); | |
1658 | } | |
1659 | ||
fe16c7dd | 1660 | success: |
644ddbb7 VSO |
1661 | if (release_stored) { |
1662 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1663 | if (bm->dirty_bitmap == NULL) { | |
1664 | continue; | |
1665 | } | |
9c98f145 | 1666 | |
644ddbb7 VSO |
1667 | bdrv_release_dirty_bitmap(bm->dirty_bitmap); |
1668 | } | |
9c98f145 VSO |
1669 | } |
1670 | ||
5f72826e VSO |
1671 | bitmap_list_free(bm_list); |
1672 | return; | |
1673 | ||
1674 | fail: | |
1675 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
fe16c7dd HR |
1676 | if (bm->dirty_bitmap == NULL || bm->table.offset == 0 || |
1677 | bdrv_dirty_bitmap_readonly(bm->dirty_bitmap)) | |
1678 | { | |
5f72826e VSO |
1679 | continue; |
1680 | } | |
1681 | ||
1682 | free_bitmap_clusters(bs, &bm->table); | |
1683 | } | |
1684 | ||
1685 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1686 | g_free(tb); | |
1687 | } | |
1688 | ||
1689 | bitmap_list_free(bm_list); | |
1690 | } | |
169b8793 VSO |
1691 | |
1692 | int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp) | |
1693 | { | |
1694 | BdrvDirtyBitmap *bitmap; | |
1695 | Error *local_err = NULL; | |
1696 | ||
644ddbb7 | 1697 | qcow2_store_persistent_dirty_bitmaps(bs, false, &local_err); |
169b8793 VSO |
1698 | if (local_err != NULL) { |
1699 | error_propagate(errp, local_err); | |
1700 | return -EINVAL; | |
1701 | } | |
1702 | ||
ef9041a7 | 1703 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
796a3798 | 1704 | if (bdrv_dirty_bitmap_get_persistence(bitmap)) { |
169b8793 VSO |
1705 | bdrv_dirty_bitmap_set_readonly(bitmap, true); |
1706 | } | |
1707 | } | |
1708 | ||
1709 | return 0; | |
1710 | } | |
da0eb242 | 1711 | |
d2c3080e VSO |
1712 | bool coroutine_fn qcow2_co_can_store_new_dirty_bitmap(BlockDriverState *bs, |
1713 | const char *name, | |
1714 | uint32_t granularity, | |
1715 | Error **errp) | |
da0eb242 VSO |
1716 | { |
1717 | BDRVQcow2State *s = bs->opaque; | |
a1db8733 VSO |
1718 | BdrvDirtyBitmap *bitmap; |
1719 | uint64_t bitmap_directory_size = 0; | |
1720 | uint32_t nb_bitmaps = 0; | |
1721 | ||
1722 | if (bdrv_find_dirty_bitmap(bs, name)) { | |
1723 | error_setg(errp, "Bitmap already exists: %s", name); | |
1724 | return false; | |
1725 | } | |
da0eb242 | 1726 | |
c9ceb3ec HR |
1727 | if (s->qcow_version < 3) { |
1728 | /* Without autoclear_features, we would always have to assume | |
1729 | * that a program without persistent dirty bitmap support has | |
1730 | * accessed this qcow2 file when opening it, and would thus | |
1731 | * have to drop all dirty bitmaps (defeating their purpose). | |
1732 | */ | |
1733 | error_setg(errp, "Cannot store dirty bitmaps in qcow2 v2 files"); | |
1734 | goto fail; | |
1735 | } | |
1736 | ||
da0eb242 VSO |
1737 | if (check_constraints_on_bitmap(bs, name, granularity, errp) != 0) { |
1738 | goto fail; | |
1739 | } | |
1740 | ||
a1db8733 VSO |
1741 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
1742 | if (bdrv_dirty_bitmap_get_persistence(bitmap)) { | |
1743 | nb_bitmaps++; | |
1744 | bitmap_directory_size += | |
1745 | calc_dir_entry_size(strlen(bdrv_dirty_bitmap_name(bitmap)), 0); | |
1746 | } | |
da0eb242 | 1747 | } |
a1db8733 VSO |
1748 | nb_bitmaps++; |
1749 | bitmap_directory_size += calc_dir_entry_size(strlen(name), 0); | |
da0eb242 | 1750 | |
a1db8733 | 1751 | if (nb_bitmaps > QCOW2_MAX_BITMAPS) { |
da0eb242 VSO |
1752 | error_setg(errp, |
1753 | "Maximum number of persistent bitmaps is already reached"); | |
1754 | goto fail; | |
1755 | } | |
1756 | ||
a1db8733 | 1757 | if (bitmap_directory_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { |
da0eb242 VSO |
1758 | error_setg(errp, "Not enough space in the bitmap directory"); |
1759 | goto fail; | |
1760 | } | |
1761 | ||
da0eb242 VSO |
1762 | return true; |
1763 | ||
1764 | fail: | |
1765 | error_prepend(errp, "Can't make bitmap '%s' persistent in '%s': ", | |
1766 | name, bdrv_get_device_or_node_name(bs)); | |
1767 | return false; | |
1768 | } | |
ef893b5c EB |
1769 | |
1770 | bool qcow2_supports_persistent_dirty_bitmap(BlockDriverState *bs) | |
1771 | { | |
1772 | BDRVQcow2State *s = bs->opaque; | |
1773 | ||
1774 | return s->qcow_version >= 3; | |
1775 | } | |
5d72c68b EB |
1776 | |
1777 | /* | |
f17d6847 | 1778 | * Compute the space required to copy bitmaps from @in_bs. |
5d72c68b EB |
1779 | * |
1780 | * The computation is based as if copying to a new image with the | |
f17d6847 EB |
1781 | * given @cluster_size, which may differ from the cluster size in |
1782 | * @in_bs; in fact, @in_bs might be something other than qcow2. | |
5d72c68b | 1783 | */ |
f17d6847 | 1784 | uint64_t qcow2_get_persistent_dirty_bitmap_size(BlockDriverState *in_bs, |
5d72c68b EB |
1785 | uint32_t cluster_size) |
1786 | { | |
1787 | uint64_t bitmaps_size = 0; | |
1788 | BdrvDirtyBitmap *bm; | |
1789 | size_t bitmap_dir_size = 0; | |
1790 | ||
f17d6847 | 1791 | FOR_EACH_DIRTY_BITMAP(in_bs, bm) { |
5d72c68b EB |
1792 | if (bdrv_dirty_bitmap_get_persistence(bm)) { |
1793 | const char *name = bdrv_dirty_bitmap_name(bm); | |
1794 | uint32_t granularity = bdrv_dirty_bitmap_granularity(bm); | |
1795 | uint64_t bmbytes = | |
1796 | get_bitmap_bytes_needed(bdrv_dirty_bitmap_size(bm), | |
1797 | granularity); | |
1798 | uint64_t bmclusters = DIV_ROUND_UP(bmbytes, cluster_size); | |
1799 | ||
1800 | /* Assume the entire bitmap is allocated */ | |
1801 | bitmaps_size += bmclusters * cluster_size; | |
1802 | /* Also reserve space for the bitmap table entries */ | |
02b1ecfa | 1803 | bitmaps_size += ROUND_UP(bmclusters * BME_TABLE_ENTRY_SIZE, |
5d72c68b EB |
1804 | cluster_size); |
1805 | /* And space for contribution to bitmap directory size */ | |
1806 | bitmap_dir_size += calc_dir_entry_size(strlen(name), 0); | |
1807 | } | |
1808 | } | |
1809 | bitmaps_size += ROUND_UP(bitmap_dir_size, cluster_size); | |
1810 | ||
1811 | return bitmaps_size; | |
1812 | } |