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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 | ||
cf7c49cf EB |
45 | QEMU_BUILD_BUG_ON(BME_MAX_NAME_SIZE != BDRV_BITMAP_MAX_NAME_SIZE); |
46 | ||
5f72826e VSO |
47 | #if BME_MAX_TABLE_SIZE * 8ULL > INT_MAX |
48 | #error In the code bitmap table physical size assumed to fit into int | |
49 | #endif | |
50 | ||
88ddffae VSO |
51 | /* Bitmap directory entry flags */ |
52 | #define BME_RESERVED_FLAGS 0xfffffffcU | |
d1258dd0 VSO |
53 | #define BME_FLAG_IN_USE (1U << 0) |
54 | #define BME_FLAG_AUTO (1U << 1) | |
88ddffae VSO |
55 | |
56 | /* bits [1, 8] U [56, 63] are reserved */ | |
57 | #define BME_TABLE_ENTRY_RESERVED_MASK 0xff000000000001feULL | |
58 | #define BME_TABLE_ENTRY_OFFSET_MASK 0x00fffffffffffe00ULL | |
59 | #define BME_TABLE_ENTRY_FLAG_ALL_ONES (1ULL << 0) | |
60 | ||
61 | typedef struct QEMU_PACKED Qcow2BitmapDirEntry { | |
62 | /* header is 8 byte aligned */ | |
63 | uint64_t bitmap_table_offset; | |
64 | ||
65 | uint32_t bitmap_table_size; | |
66 | uint32_t flags; | |
67 | ||
68 | uint8_t type; | |
69 | uint8_t granularity_bits; | |
70 | uint16_t name_size; | |
71 | uint32_t extra_data_size; | |
72 | /* extra data follows */ | |
73 | /* name follows */ | |
74 | } Qcow2BitmapDirEntry; | |
75 | ||
76 | typedef struct Qcow2BitmapTable { | |
77 | uint64_t offset; | |
78 | uint32_t size; /* number of 64bit entries */ | |
79 | QSIMPLEQ_ENTRY(Qcow2BitmapTable) entry; | |
80 | } Qcow2BitmapTable; | |
81 | ||
82 | typedef struct Qcow2Bitmap { | |
83 | Qcow2BitmapTable table; | |
84 | uint32_t flags; | |
85 | uint8_t granularity_bits; | |
86 | char *name; | |
87 | ||
5f72826e VSO |
88 | BdrvDirtyBitmap *dirty_bitmap; |
89 | ||
88ddffae VSO |
90 | QSIMPLEQ_ENTRY(Qcow2Bitmap) entry; |
91 | } Qcow2Bitmap; | |
92 | typedef QSIMPLEQ_HEAD(Qcow2BitmapList, Qcow2Bitmap) Qcow2BitmapList; | |
93 | ||
94 | typedef enum BitmapType { | |
95 | BT_DIRTY_TRACKING_BITMAP = 1 | |
96 | } BitmapType; | |
97 | ||
d1258dd0 VSO |
98 | static inline bool can_write(BlockDriverState *bs) |
99 | { | |
100 | return !bdrv_is_read_only(bs) && !(bdrv_get_flags(bs) & BDRV_O_INACTIVE); | |
101 | } | |
102 | ||
103 | static int update_header_sync(BlockDriverState *bs) | |
104 | { | |
105 | int ret; | |
106 | ||
107 | ret = qcow2_update_header(bs); | |
108 | if (ret < 0) { | |
109 | return ret; | |
110 | } | |
111 | ||
1a0c2bfb | 112 | return bdrv_flush(bs->file->bs); |
d1258dd0 VSO |
113 | } |
114 | ||
5f72826e VSO |
115 | static inline void bitmap_table_to_be(uint64_t *bitmap_table, size_t size) |
116 | { | |
117 | size_t i; | |
118 | ||
119 | for (i = 0; i < size; ++i) { | |
caacea4b | 120 | bitmap_table[i] = cpu_to_be64(bitmap_table[i]); |
5f72826e VSO |
121 | } |
122 | } | |
123 | ||
88ddffae VSO |
124 | static int check_table_entry(uint64_t entry, int cluster_size) |
125 | { | |
126 | uint64_t offset; | |
127 | ||
128 | if (entry & BME_TABLE_ENTRY_RESERVED_MASK) { | |
129 | return -EINVAL; | |
130 | } | |
131 | ||
132 | offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
133 | if (offset != 0) { | |
134 | /* if offset specified, bit 0 is reserved */ | |
135 | if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) { | |
136 | return -EINVAL; | |
137 | } | |
138 | ||
139 | if (offset % cluster_size != 0) { | |
140 | return -EINVAL; | |
141 | } | |
142 | } | |
143 | ||
144 | return 0; | |
145 | } | |
146 | ||
570542ec T |
147 | static int64_t get_bitmap_bytes_needed(int64_t len, uint32_t granularity) |
148 | { | |
149 | int64_t num_bits = DIV_ROUND_UP(len, granularity); | |
150 | ||
151 | return DIV_ROUND_UP(num_bits, 8); | |
152 | } | |
153 | ||
5f72826e VSO |
154 | static int check_constraints_on_bitmap(BlockDriverState *bs, |
155 | const char *name, | |
156 | uint32_t granularity, | |
157 | Error **errp) | |
158 | { | |
159 | BDRVQcow2State *s = bs->opaque; | |
160 | int granularity_bits = ctz32(granularity); | |
161 | int64_t len = bdrv_getlength(bs); | |
570542ec | 162 | int64_t bitmap_bytes; |
5f72826e VSO |
163 | |
164 | assert(granularity > 0); | |
165 | assert((granularity & (granularity - 1)) == 0); | |
166 | ||
167 | if (len < 0) { | |
168 | error_setg_errno(errp, -len, "Failed to get size of '%s'", | |
169 | bdrv_get_device_or_node_name(bs)); | |
170 | return len; | |
171 | } | |
172 | ||
173 | if (granularity_bits > BME_MAX_GRANULARITY_BITS) { | |
174 | error_setg(errp, "Granularity exceeds maximum (%llu bytes)", | |
175 | 1ULL << BME_MAX_GRANULARITY_BITS); | |
176 | return -EINVAL; | |
177 | } | |
178 | if (granularity_bits < BME_MIN_GRANULARITY_BITS) { | |
179 | error_setg(errp, "Granularity is under minimum (%llu bytes)", | |
180 | 1ULL << BME_MIN_GRANULARITY_BITS); | |
181 | return -EINVAL; | |
182 | } | |
183 | ||
570542ec T |
184 | bitmap_bytes = get_bitmap_bytes_needed(len, granularity); |
185 | if ((bitmap_bytes > (uint64_t)BME_MAX_PHYS_SIZE) || | |
186 | (bitmap_bytes > (uint64_t)BME_MAX_TABLE_SIZE * s->cluster_size)) | |
5f72826e VSO |
187 | { |
188 | error_setg(errp, "Too much space will be occupied by the bitmap. " | |
189 | "Use larger granularity"); | |
190 | return -EINVAL; | |
191 | } | |
192 | ||
193 | if (strlen(name) > BME_MAX_NAME_SIZE) { | |
194 | error_setg(errp, "Name length exceeds maximum (%u characters)", | |
195 | BME_MAX_NAME_SIZE); | |
196 | return -EINVAL; | |
197 | } | |
198 | ||
199 | return 0; | |
200 | } | |
201 | ||
202 | static void clear_bitmap_table(BlockDriverState *bs, uint64_t *bitmap_table, | |
203 | uint32_t bitmap_table_size) | |
204 | { | |
205 | BDRVQcow2State *s = bs->opaque; | |
206 | int i; | |
207 | ||
208 | for (i = 0; i < bitmap_table_size; ++i) { | |
209 | uint64_t addr = bitmap_table[i] & BME_TABLE_ENTRY_OFFSET_MASK; | |
210 | if (!addr) { | |
211 | continue; | |
212 | } | |
213 | ||
444b8236 | 214 | qcow2_free_clusters(bs, addr, s->cluster_size, QCOW2_DISCARD_ALWAYS); |
5f72826e VSO |
215 | bitmap_table[i] = 0; |
216 | } | |
217 | } | |
218 | ||
88ddffae VSO |
219 | static int bitmap_table_load(BlockDriverState *bs, Qcow2BitmapTable *tb, |
220 | uint64_t **bitmap_table) | |
221 | { | |
222 | int ret; | |
223 | BDRVQcow2State *s = bs->opaque; | |
224 | uint32_t i; | |
225 | uint64_t *table; | |
226 | ||
227 | assert(tb->size != 0); | |
228 | table = g_try_new(uint64_t, tb->size); | |
229 | if (table == NULL) { | |
230 | return -ENOMEM; | |
231 | } | |
232 | ||
233 | assert(tb->size <= BME_MAX_TABLE_SIZE); | |
234 | ret = bdrv_pread(bs->file, tb->offset, | |
235 | table, tb->size * sizeof(uint64_t)); | |
236 | if (ret < 0) { | |
237 | goto fail; | |
238 | } | |
239 | ||
240 | for (i = 0; i < tb->size; ++i) { | |
caacea4b | 241 | table[i] = be64_to_cpu(table[i]); |
88ddffae VSO |
242 | ret = check_table_entry(table[i], s->cluster_size); |
243 | if (ret < 0) { | |
244 | goto fail; | |
245 | } | |
246 | } | |
247 | ||
248 | *bitmap_table = table; | |
249 | return 0; | |
250 | ||
251 | fail: | |
252 | g_free(table); | |
253 | ||
254 | return ret; | |
255 | } | |
256 | ||
5f72826e VSO |
257 | static int free_bitmap_clusters(BlockDriverState *bs, Qcow2BitmapTable *tb) |
258 | { | |
259 | int ret; | |
260 | uint64_t *bitmap_table; | |
261 | ||
262 | ret = bitmap_table_load(bs, tb, &bitmap_table); | |
263 | if (ret < 0) { | |
5f72826e VSO |
264 | return ret; |
265 | } | |
266 | ||
267 | clear_bitmap_table(bs, bitmap_table, tb->size); | |
268 | qcow2_free_clusters(bs, tb->offset, tb->size * sizeof(uint64_t), | |
269 | QCOW2_DISCARD_OTHER); | |
270 | g_free(bitmap_table); | |
271 | ||
272 | tb->offset = 0; | |
273 | tb->size = 0; | |
274 | ||
275 | return 0; | |
276 | } | |
277 | ||
c7e7c87a EB |
278 | /* Return the disk size covered by a single qcow2 cluster of bitmap data. */ |
279 | static uint64_t bytes_covered_by_bitmap_cluster(const BDRVQcow2State *s, | |
280 | const BdrvDirtyBitmap *bitmap) | |
d1258dd0 | 281 | { |
c7e7c87a EB |
282 | uint64_t granularity = bdrv_dirty_bitmap_granularity(bitmap); |
283 | uint64_t limit = granularity * (s->cluster_size << 3); | |
d1258dd0 | 284 | |
c7e7c87a | 285 | assert(QEMU_IS_ALIGNED(limit, |
113754f3 | 286 | bdrv_dirty_bitmap_serialization_align(bitmap))); |
c7e7c87a | 287 | return limit; |
d1258dd0 VSO |
288 | } |
289 | ||
290 | /* load_bitmap_data | |
291 | * @bitmap_table entries must satisfy specification constraints. | |
292 | * @bitmap must be cleared */ | |
293 | static int load_bitmap_data(BlockDriverState *bs, | |
294 | const uint64_t *bitmap_table, | |
295 | uint32_t bitmap_table_size, | |
296 | BdrvDirtyBitmap *bitmap) | |
297 | { | |
298 | int ret = 0; | |
299 | BDRVQcow2State *s = bs->opaque; | |
ab94db6f | 300 | uint64_t offset, limit; |
d1258dd0 VSO |
301 | uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); |
302 | uint8_t *buf = NULL; | |
303 | uint64_t i, tab_size = | |
304 | size_to_clusters(s, | |
86f6ae67 | 305 | bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size)); |
d1258dd0 VSO |
306 | |
307 | if (tab_size != bitmap_table_size || tab_size > BME_MAX_TABLE_SIZE) { | |
308 | return -EINVAL; | |
309 | } | |
310 | ||
311 | buf = g_malloc(s->cluster_size); | |
c7e7c87a | 312 | limit = bytes_covered_by_bitmap_cluster(s, bitmap); |
ab94db6f EB |
313 | for (i = 0, offset = 0; i < tab_size; ++i, offset += limit) { |
314 | uint64_t count = MIN(bm_size - offset, limit); | |
d1258dd0 | 315 | uint64_t entry = bitmap_table[i]; |
ab94db6f | 316 | uint64_t data_offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; |
d1258dd0 VSO |
317 | |
318 | assert(check_table_entry(entry, s->cluster_size) == 0); | |
319 | ||
ab94db6f | 320 | if (data_offset == 0) { |
d1258dd0 | 321 | if (entry & BME_TABLE_ENTRY_FLAG_ALL_ONES) { |
ab94db6f | 322 | bdrv_dirty_bitmap_deserialize_ones(bitmap, offset, count, |
d1258dd0 VSO |
323 | false); |
324 | } else { | |
325 | /* No need to deserialize zeros because the dirty bitmap is | |
326 | * already cleared */ | |
327 | } | |
328 | } else { | |
ab94db6f | 329 | ret = bdrv_pread(bs->file, data_offset, buf, s->cluster_size); |
d1258dd0 VSO |
330 | if (ret < 0) { |
331 | goto finish; | |
332 | } | |
ab94db6f | 333 | bdrv_dirty_bitmap_deserialize_part(bitmap, buf, offset, count, |
d1258dd0 VSO |
334 | false); |
335 | } | |
336 | } | |
337 | ret = 0; | |
338 | ||
339 | bdrv_dirty_bitmap_deserialize_finish(bitmap); | |
340 | ||
341 | finish: | |
342 | g_free(buf); | |
343 | ||
344 | return ret; | |
345 | } | |
346 | ||
347 | static BdrvDirtyBitmap *load_bitmap(BlockDriverState *bs, | |
348 | Qcow2Bitmap *bm, Error **errp) | |
349 | { | |
350 | int ret; | |
351 | uint64_t *bitmap_table = NULL; | |
352 | uint32_t granularity; | |
353 | BdrvDirtyBitmap *bitmap = NULL; | |
354 | ||
74da6b94 JS |
355 | granularity = 1U << bm->granularity_bits; |
356 | bitmap = bdrv_create_dirty_bitmap(bs, granularity, bm->name, errp); | |
357 | if (bitmap == NULL) { | |
d1258dd0 VSO |
358 | goto fail; |
359 | } | |
360 | ||
74da6b94 JS |
361 | if (bm->flags & BME_FLAG_IN_USE) { |
362 | /* Data is unusable, skip loading it */ | |
363 | return bitmap; | |
364 | } | |
365 | ||
d1258dd0 VSO |
366 | ret = bitmap_table_load(bs, &bm->table, &bitmap_table); |
367 | if (ret < 0) { | |
368 | error_setg_errno(errp, -ret, | |
369 | "Could not read bitmap_table table from image for " | |
370 | "bitmap '%s'", bm->name); | |
371 | goto fail; | |
372 | } | |
373 | ||
d1258dd0 VSO |
374 | ret = load_bitmap_data(bs, bitmap_table, bm->table.size, bitmap); |
375 | if (ret < 0) { | |
376 | error_setg_errno(errp, -ret, "Could not read bitmap '%s' from image", | |
377 | bm->name); | |
378 | goto fail; | |
379 | } | |
380 | ||
381 | g_free(bitmap_table); | |
382 | return bitmap; | |
383 | ||
384 | fail: | |
385 | g_free(bitmap_table); | |
386 | if (bitmap != NULL) { | |
5deb6cbd | 387 | bdrv_release_dirty_bitmap(bitmap); |
d1258dd0 VSO |
388 | } |
389 | ||
390 | return NULL; | |
391 | } | |
392 | ||
88ddffae VSO |
393 | /* |
394 | * Bitmap List | |
395 | */ | |
396 | ||
397 | /* | |
398 | * Bitmap List private functions | |
399 | * Only Bitmap List knows about bitmap directory structure in Qcow2. | |
400 | */ | |
401 | ||
402 | static inline void bitmap_dir_entry_to_cpu(Qcow2BitmapDirEntry *entry) | |
403 | { | |
caacea4b PM |
404 | entry->bitmap_table_offset = be64_to_cpu(entry->bitmap_table_offset); |
405 | entry->bitmap_table_size = be32_to_cpu(entry->bitmap_table_size); | |
406 | entry->flags = be32_to_cpu(entry->flags); | |
407 | entry->name_size = be16_to_cpu(entry->name_size); | |
408 | entry->extra_data_size = be32_to_cpu(entry->extra_data_size); | |
88ddffae VSO |
409 | } |
410 | ||
d1258dd0 VSO |
411 | static inline void bitmap_dir_entry_to_be(Qcow2BitmapDirEntry *entry) |
412 | { | |
caacea4b PM |
413 | entry->bitmap_table_offset = cpu_to_be64(entry->bitmap_table_offset); |
414 | entry->bitmap_table_size = cpu_to_be32(entry->bitmap_table_size); | |
415 | entry->flags = cpu_to_be32(entry->flags); | |
416 | entry->name_size = cpu_to_be16(entry->name_size); | |
417 | entry->extra_data_size = cpu_to_be32(entry->extra_data_size); | |
d1258dd0 VSO |
418 | } |
419 | ||
88ddffae VSO |
420 | static inline int calc_dir_entry_size(size_t name_size, size_t extra_data_size) |
421 | { | |
9e029689 AG |
422 | int size = sizeof(Qcow2BitmapDirEntry) + name_size + extra_data_size; |
423 | return ROUND_UP(size, 8); | |
88ddffae VSO |
424 | } |
425 | ||
426 | static inline int dir_entry_size(Qcow2BitmapDirEntry *entry) | |
427 | { | |
428 | return calc_dir_entry_size(entry->name_size, entry->extra_data_size); | |
429 | } | |
430 | ||
431 | static inline const char *dir_entry_name_field(Qcow2BitmapDirEntry *entry) | |
432 | { | |
433 | return (const char *)(entry + 1) + entry->extra_data_size; | |
434 | } | |
435 | ||
436 | static inline char *dir_entry_copy_name(Qcow2BitmapDirEntry *entry) | |
437 | { | |
438 | const char *name_field = dir_entry_name_field(entry); | |
439 | return g_strndup(name_field, entry->name_size); | |
440 | } | |
441 | ||
442 | static inline Qcow2BitmapDirEntry *next_dir_entry(Qcow2BitmapDirEntry *entry) | |
443 | { | |
444 | return (Qcow2BitmapDirEntry *)((uint8_t *)entry + dir_entry_size(entry)); | |
445 | } | |
446 | ||
447 | static int check_dir_entry(BlockDriverState *bs, Qcow2BitmapDirEntry *entry) | |
448 | { | |
449 | BDRVQcow2State *s = bs->opaque; | |
450 | uint64_t phys_bitmap_bytes; | |
451 | int64_t len; | |
452 | ||
453 | bool fail = (entry->bitmap_table_size == 0) || | |
454 | (entry->bitmap_table_offset == 0) || | |
455 | (entry->bitmap_table_offset % s->cluster_size) || | |
456 | (entry->bitmap_table_size > BME_MAX_TABLE_SIZE) || | |
457 | (entry->granularity_bits > BME_MAX_GRANULARITY_BITS) || | |
458 | (entry->granularity_bits < BME_MIN_GRANULARITY_BITS) || | |
459 | (entry->flags & BME_RESERVED_FLAGS) || | |
460 | (entry->name_size > BME_MAX_NAME_SIZE) || | |
461 | (entry->type != BT_DIRTY_TRACKING_BITMAP); | |
462 | ||
463 | if (fail) { | |
464 | return -EINVAL; | |
465 | } | |
466 | ||
467 | phys_bitmap_bytes = (uint64_t)entry->bitmap_table_size * s->cluster_size; | |
468 | len = bdrv_getlength(bs); | |
469 | ||
470 | if (len < 0) { | |
471 | return len; | |
472 | } | |
473 | ||
bf5f0cf5 VSO |
474 | if (phys_bitmap_bytes > BME_MAX_PHYS_SIZE) { |
475 | return -EINVAL; | |
476 | } | |
88ddffae | 477 | |
bf5f0cf5 VSO |
478 | if (!(entry->flags & BME_FLAG_IN_USE) && |
479 | (len > ((phys_bitmap_bytes * 8) << entry->granularity_bits))) | |
480 | { | |
481 | /* | |
482 | * We've loaded a valid bitmap (IN_USE not set) or we are going to | |
483 | * store a valid bitmap, but the allocated bitmap table size is not | |
484 | * enough to store this bitmap. | |
485 | * | |
486 | * Note, that it's OK to have an invalid bitmap with invalid size due | |
487 | * to a bitmap that was not correctly saved after image resize. | |
488 | */ | |
489 | return -EINVAL; | |
490 | } | |
491 | ||
492 | return 0; | |
88ddffae VSO |
493 | } |
494 | ||
d1258dd0 VSO |
495 | static inline void bitmap_directory_to_be(uint8_t *dir, size_t size) |
496 | { | |
497 | uint8_t *end = dir + size; | |
498 | while (dir < end) { | |
499 | Qcow2BitmapDirEntry *e = (Qcow2BitmapDirEntry *)dir; | |
500 | dir += dir_entry_size(e); | |
501 | ||
502 | bitmap_dir_entry_to_be(e); | |
503 | } | |
504 | } | |
505 | ||
88ddffae VSO |
506 | /* |
507 | * Bitmap List public functions | |
508 | */ | |
509 | ||
510 | static void bitmap_free(Qcow2Bitmap *bm) | |
511 | { | |
b6b75a99 VSO |
512 | if (bm == NULL) { |
513 | return; | |
514 | } | |
515 | ||
88ddffae VSO |
516 | g_free(bm->name); |
517 | g_free(bm); | |
518 | } | |
519 | ||
520 | static void bitmap_list_free(Qcow2BitmapList *bm_list) | |
521 | { | |
522 | Qcow2Bitmap *bm; | |
523 | ||
524 | if (bm_list == NULL) { | |
525 | return; | |
526 | } | |
527 | ||
528 | while ((bm = QSIMPLEQ_FIRST(bm_list)) != NULL) { | |
529 | QSIMPLEQ_REMOVE_HEAD(bm_list, entry); | |
530 | bitmap_free(bm); | |
531 | } | |
532 | ||
533 | g_free(bm_list); | |
534 | } | |
535 | ||
536 | static Qcow2BitmapList *bitmap_list_new(void) | |
537 | { | |
538 | Qcow2BitmapList *bm_list = g_new(Qcow2BitmapList, 1); | |
539 | QSIMPLEQ_INIT(bm_list); | |
540 | ||
541 | return bm_list; | |
542 | } | |
543 | ||
d1258dd0 VSO |
544 | static uint32_t bitmap_list_count(Qcow2BitmapList *bm_list) |
545 | { | |
546 | Qcow2Bitmap *bm; | |
547 | uint32_t nb_bitmaps = 0; | |
548 | ||
549 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
550 | nb_bitmaps++; | |
551 | } | |
552 | ||
553 | return nb_bitmaps; | |
554 | } | |
555 | ||
88ddffae VSO |
556 | /* bitmap_list_load |
557 | * Get bitmap list from qcow2 image. Actually reads bitmap directory, | |
558 | * checks it and convert to bitmap list. | |
559 | */ | |
560 | static Qcow2BitmapList *bitmap_list_load(BlockDriverState *bs, uint64_t offset, | |
561 | uint64_t size, Error **errp) | |
562 | { | |
563 | int ret; | |
564 | BDRVQcow2State *s = bs->opaque; | |
565 | uint8_t *dir, *dir_end; | |
566 | Qcow2BitmapDirEntry *e; | |
567 | uint32_t nb_dir_entries = 0; | |
568 | Qcow2BitmapList *bm_list = NULL; | |
569 | ||
570 | if (size == 0) { | |
571 | error_setg(errp, "Requested bitmap directory size is zero"); | |
572 | return NULL; | |
573 | } | |
574 | ||
575 | if (size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
576 | error_setg(errp, "Requested bitmap directory size is too big"); | |
577 | return NULL; | |
578 | } | |
579 | ||
580 | dir = g_try_malloc(size); | |
581 | if (dir == NULL) { | |
582 | error_setg(errp, "Failed to allocate space for bitmap directory"); | |
583 | return NULL; | |
584 | } | |
585 | dir_end = dir + size; | |
586 | ||
587 | ret = bdrv_pread(bs->file, offset, dir, size); | |
588 | if (ret < 0) { | |
589 | error_setg_errno(errp, -ret, "Failed to read bitmap directory"); | |
590 | goto fail; | |
591 | } | |
592 | ||
593 | bm_list = bitmap_list_new(); | |
594 | for (e = (Qcow2BitmapDirEntry *)dir; | |
595 | e < (Qcow2BitmapDirEntry *)dir_end; | |
596 | e = next_dir_entry(e)) | |
597 | { | |
598 | Qcow2Bitmap *bm; | |
599 | ||
600 | if ((uint8_t *)(e + 1) > dir_end) { | |
601 | goto broken_dir; | |
602 | } | |
603 | ||
604 | if (++nb_dir_entries > s->nb_bitmaps) { | |
605 | error_setg(errp, "More bitmaps found than specified in header" | |
606 | " extension"); | |
607 | goto fail; | |
608 | } | |
609 | bitmap_dir_entry_to_cpu(e); | |
610 | ||
611 | if ((uint8_t *)next_dir_entry(e) > dir_end) { | |
612 | goto broken_dir; | |
613 | } | |
614 | ||
615 | if (e->extra_data_size != 0) { | |
616 | error_setg(errp, "Bitmap extra data is not supported"); | |
617 | goto fail; | |
618 | } | |
619 | ||
620 | ret = check_dir_entry(bs, e); | |
621 | if (ret < 0) { | |
622 | error_setg(errp, "Bitmap '%.*s' doesn't satisfy the constraints", | |
623 | e->name_size, dir_entry_name_field(e)); | |
624 | goto fail; | |
625 | } | |
626 | ||
5330f32b | 627 | bm = g_new0(Qcow2Bitmap, 1); |
88ddffae VSO |
628 | bm->table.offset = e->bitmap_table_offset; |
629 | bm->table.size = e->bitmap_table_size; | |
630 | bm->flags = e->flags; | |
631 | bm->granularity_bits = e->granularity_bits; | |
632 | bm->name = dir_entry_copy_name(e); | |
633 | QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry); | |
634 | } | |
635 | ||
636 | if (nb_dir_entries != s->nb_bitmaps) { | |
637 | error_setg(errp, "Less bitmaps found than specified in header" | |
638 | " extension"); | |
639 | goto fail; | |
640 | } | |
641 | ||
642 | if ((uint8_t *)e != dir_end) { | |
643 | goto broken_dir; | |
644 | } | |
645 | ||
646 | g_free(dir); | |
647 | return bm_list; | |
648 | ||
649 | broken_dir: | |
650 | ret = -EINVAL; | |
651 | error_setg(errp, "Broken bitmap directory"); | |
652 | ||
653 | fail: | |
654 | g_free(dir); | |
655 | bitmap_list_free(bm_list); | |
656 | ||
657 | return NULL; | |
658 | } | |
659 | ||
660 | int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, | |
661 | void **refcount_table, | |
662 | int64_t *refcount_table_size) | |
663 | { | |
664 | int ret; | |
665 | BDRVQcow2State *s = bs->opaque; | |
666 | Qcow2BitmapList *bm_list; | |
667 | Qcow2Bitmap *bm; | |
668 | ||
669 | if (s->nb_bitmaps == 0) { | |
670 | return 0; | |
671 | } | |
672 | ||
673 | ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_size, | |
674 | s->bitmap_directory_offset, | |
675 | s->bitmap_directory_size); | |
676 | if (ret < 0) { | |
677 | return ret; | |
678 | } | |
679 | ||
680 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
681 | s->bitmap_directory_size, NULL); | |
682 | if (bm_list == NULL) { | |
683 | res->corruptions++; | |
684 | return -EINVAL; | |
685 | } | |
686 | ||
687 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
688 | uint64_t *bitmap_table = NULL; | |
689 | int i; | |
690 | ||
691 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
692 | refcount_table, refcount_table_size, | |
693 | bm->table.offset, | |
694 | bm->table.size * sizeof(uint64_t)); | |
695 | if (ret < 0) { | |
696 | goto out; | |
697 | } | |
698 | ||
699 | ret = bitmap_table_load(bs, &bm->table, &bitmap_table); | |
700 | if (ret < 0) { | |
701 | res->corruptions++; | |
702 | goto out; | |
703 | } | |
704 | ||
705 | for (i = 0; i < bm->table.size; ++i) { | |
706 | uint64_t entry = bitmap_table[i]; | |
707 | uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
708 | ||
709 | if (check_table_entry(entry, s->cluster_size) < 0) { | |
710 | res->corruptions++; | |
711 | continue; | |
712 | } | |
713 | ||
714 | if (offset == 0) { | |
715 | continue; | |
716 | } | |
717 | ||
718 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
719 | refcount_table, refcount_table_size, | |
720 | offset, s->cluster_size); | |
721 | if (ret < 0) { | |
722 | g_free(bitmap_table); | |
723 | goto out; | |
724 | } | |
725 | } | |
726 | ||
727 | g_free(bitmap_table); | |
728 | } | |
729 | ||
730 | out: | |
731 | bitmap_list_free(bm_list); | |
732 | ||
733 | return ret; | |
734 | } | |
d1258dd0 VSO |
735 | |
736 | /* bitmap_list_store | |
737 | * Store bitmap list to qcow2 image as a bitmap directory. | |
738 | * Everything is checked. | |
739 | */ | |
740 | static int bitmap_list_store(BlockDriverState *bs, Qcow2BitmapList *bm_list, | |
741 | uint64_t *offset, uint64_t *size, bool in_place) | |
742 | { | |
743 | int ret; | |
744 | uint8_t *dir; | |
745 | int64_t dir_offset = 0; | |
746 | uint64_t dir_size = 0; | |
747 | Qcow2Bitmap *bm; | |
748 | Qcow2BitmapDirEntry *e; | |
749 | ||
750 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
751 | dir_size += calc_dir_entry_size(strlen(bm->name), 0); | |
752 | } | |
753 | ||
754 | if (dir_size == 0 || dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
755 | return -EINVAL; | |
756 | } | |
757 | ||
758 | if (in_place) { | |
759 | if (*size != dir_size || *offset == 0) { | |
760 | return -EINVAL; | |
761 | } | |
762 | ||
763 | dir_offset = *offset; | |
764 | } | |
765 | ||
6388903e | 766 | dir = g_try_malloc0(dir_size); |
d1258dd0 VSO |
767 | if (dir == NULL) { |
768 | return -ENOMEM; | |
769 | } | |
770 | ||
771 | e = (Qcow2BitmapDirEntry *)dir; | |
772 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
773 | e->bitmap_table_offset = bm->table.offset; | |
774 | e->bitmap_table_size = bm->table.size; | |
775 | e->flags = bm->flags; | |
776 | e->type = BT_DIRTY_TRACKING_BITMAP; | |
777 | e->granularity_bits = bm->granularity_bits; | |
778 | e->name_size = strlen(bm->name); | |
779 | e->extra_data_size = 0; | |
780 | memcpy(e + 1, bm->name, e->name_size); | |
781 | ||
782 | if (check_dir_entry(bs, e) < 0) { | |
783 | ret = -EINVAL; | |
784 | goto fail; | |
785 | } | |
786 | ||
787 | e = next_dir_entry(e); | |
788 | } | |
789 | ||
790 | bitmap_directory_to_be(dir, dir_size); | |
791 | ||
792 | if (!in_place) { | |
793 | dir_offset = qcow2_alloc_clusters(bs, dir_size); | |
794 | if (dir_offset < 0) { | |
795 | ret = dir_offset; | |
796 | goto fail; | |
797 | } | |
798 | } | |
799 | ||
0e4e4318 VSO |
800 | /* Actually, even in in-place case ignoring QCOW2_OL_BITMAP_DIRECTORY is not |
801 | * necessary, because we drop QCOW2_AUTOCLEAR_BITMAPS when updating bitmap | |
802 | * directory in-place (actually, turn-off the extension), which is checked | |
803 | * in qcow2_check_metadata_overlap() */ | |
804 | ret = qcow2_pre_write_overlap_check( | |
966b000f KW |
805 | bs, in_place ? QCOW2_OL_BITMAP_DIRECTORY : 0, dir_offset, dir_size, |
806 | false); | |
d1258dd0 VSO |
807 | if (ret < 0) { |
808 | goto fail; | |
809 | } | |
810 | ||
811 | ret = bdrv_pwrite(bs->file, dir_offset, dir, dir_size); | |
812 | if (ret < 0) { | |
813 | goto fail; | |
814 | } | |
815 | ||
816 | g_free(dir); | |
817 | ||
818 | if (!in_place) { | |
819 | *size = dir_size; | |
820 | *offset = dir_offset; | |
821 | } | |
822 | ||
823 | return 0; | |
824 | ||
825 | fail: | |
826 | g_free(dir); | |
827 | ||
828 | if (!in_place && dir_offset > 0) { | |
829 | qcow2_free_clusters(bs, dir_offset, dir_size, QCOW2_DISCARD_OTHER); | |
830 | } | |
831 | ||
832 | return ret; | |
833 | } | |
834 | ||
835 | /* | |
836 | * Bitmap List end | |
837 | */ | |
838 | ||
839 | static int update_ext_header_and_dir_in_place(BlockDriverState *bs, | |
840 | Qcow2BitmapList *bm_list) | |
841 | { | |
842 | BDRVQcow2State *s = bs->opaque; | |
843 | int ret; | |
844 | ||
845 | if (!(s->autoclear_features & QCOW2_AUTOCLEAR_BITMAPS) || | |
846 | bm_list == NULL || QSIMPLEQ_EMPTY(bm_list) || | |
847 | bitmap_list_count(bm_list) != s->nb_bitmaps) | |
848 | { | |
849 | return -EINVAL; | |
850 | } | |
851 | ||
852 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
853 | ret = update_header_sync(bs); | |
854 | if (ret < 0) { | |
855 | /* Two variants are possible here: | |
856 | * 1. Autoclear flag is dropped, all bitmaps will be lost. | |
857 | * 2. Autoclear flag is not dropped, old state is left. | |
858 | */ | |
859 | return ret; | |
860 | } | |
861 | ||
862 | /* autoclear bit is not set, so we can safely update bitmap directory */ | |
863 | ||
864 | ret = bitmap_list_store(bs, bm_list, &s->bitmap_directory_offset, | |
865 | &s->bitmap_directory_size, true); | |
866 | if (ret < 0) { | |
867 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
868 | * qemu-img check */ | |
869 | return ret; | |
870 | } | |
871 | ||
872 | ret = update_header_sync(bs); | |
873 | if (ret < 0) { | |
874 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
875 | * qemu-img check */ | |
876 | return ret; | |
877 | } | |
878 | ||
879 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
880 | return update_header_sync(bs); | |
881 | /* If final update_header_sync() fails, two variants are possible: | |
882 | * 1. Autoclear flag is not set, all bitmaps will be lost. | |
883 | * 2. Autoclear flag is set, header and directory are successfully updated. | |
884 | */ | |
885 | } | |
886 | ||
5f72826e VSO |
887 | static int update_ext_header_and_dir(BlockDriverState *bs, |
888 | Qcow2BitmapList *bm_list) | |
889 | { | |
890 | BDRVQcow2State *s = bs->opaque; | |
891 | int ret; | |
892 | uint64_t new_offset = 0; | |
893 | uint64_t new_size = 0; | |
894 | uint32_t new_nb_bitmaps = 0; | |
895 | uint64_t old_offset = s->bitmap_directory_offset; | |
896 | uint64_t old_size = s->bitmap_directory_size; | |
897 | uint32_t old_nb_bitmaps = s->nb_bitmaps; | |
898 | uint64_t old_autocl = s->autoclear_features; | |
899 | ||
900 | if (bm_list != NULL && !QSIMPLEQ_EMPTY(bm_list)) { | |
901 | new_nb_bitmaps = bitmap_list_count(bm_list); | |
902 | ||
903 | if (new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
904 | return -EINVAL; | |
905 | } | |
906 | ||
907 | ret = bitmap_list_store(bs, bm_list, &new_offset, &new_size, false); | |
908 | if (ret < 0) { | |
909 | return ret; | |
910 | } | |
911 | ||
1a0c2bfb | 912 | ret = qcow2_flush_caches(bs); |
5f72826e VSO |
913 | if (ret < 0) { |
914 | goto fail; | |
915 | } | |
916 | ||
917 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
918 | } else { | |
919 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
920 | } | |
921 | ||
922 | s->bitmap_directory_offset = new_offset; | |
923 | s->bitmap_directory_size = new_size; | |
924 | s->nb_bitmaps = new_nb_bitmaps; | |
925 | ||
926 | ret = update_header_sync(bs); | |
927 | if (ret < 0) { | |
928 | goto fail; | |
929 | } | |
930 | ||
931 | if (old_size > 0) { | |
932 | qcow2_free_clusters(bs, old_offset, old_size, QCOW2_DISCARD_OTHER); | |
933 | } | |
934 | ||
935 | return 0; | |
936 | ||
937 | fail: | |
938 | if (new_offset > 0) { | |
939 | qcow2_free_clusters(bs, new_offset, new_size, QCOW2_DISCARD_OTHER); | |
940 | } | |
941 | ||
942 | s->bitmap_directory_offset = old_offset; | |
943 | s->bitmap_directory_size = old_size; | |
944 | s->nb_bitmaps = old_nb_bitmaps; | |
945 | s->autoclear_features = old_autocl; | |
946 | ||
947 | return ret; | |
948 | } | |
949 | ||
d1258dd0 VSO |
950 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ |
951 | static void release_dirty_bitmap_helper(gpointer bitmap, | |
952 | gpointer bs) | |
953 | { | |
5deb6cbd | 954 | bdrv_release_dirty_bitmap(bitmap); |
d1258dd0 VSO |
955 | } |
956 | ||
957 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ | |
958 | static void set_readonly_helper(gpointer bitmap, gpointer value) | |
959 | { | |
960 | bdrv_dirty_bitmap_set_readonly(bitmap, (bool)value); | |
961 | } | |
962 | ||
3e99da5e | 963 | /* qcow2_load_dirty_bitmaps() |
d1258dd0 VSO |
964 | * Return value is a hint for caller: true means that the Qcow2 header was |
965 | * updated. (false doesn't mean that the header should be updated by the | |
966 | * caller, it just means that updating was not needed or the image cannot be | |
967 | * written to). | |
968 | * On failure the function returns false. | |
969 | */ | |
3e99da5e | 970 | bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) |
d1258dd0 VSO |
971 | { |
972 | BDRVQcow2State *s = bs->opaque; | |
973 | Qcow2BitmapList *bm_list; | |
974 | Qcow2Bitmap *bm; | |
975 | GSList *created_dirty_bitmaps = NULL; | |
976 | bool header_updated = false; | |
74da6b94 | 977 | bool needs_update = false; |
d1258dd0 VSO |
978 | |
979 | if (s->nb_bitmaps == 0) { | |
980 | /* No bitmaps - nothing to do */ | |
981 | return false; | |
982 | } | |
983 | ||
984 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
985 | s->bitmap_directory_size, errp); | |
986 | if (bm_list == NULL) { | |
987 | return false; | |
988 | } | |
989 | ||
990 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
a505475b VSO |
991 | BdrvDirtyBitmap *bitmap; |
992 | ||
993 | if ((bm->flags & BME_FLAG_IN_USE) && | |
994 | bdrv_find_dirty_bitmap(bs, bm->name)) | |
995 | { | |
996 | /* | |
997 | * We already have corresponding BdrvDirtyBitmap, and bitmap in the | |
998 | * image is marked IN_USE. Firstly, this state is valid, no reason | |
999 | * to consider existing BdrvDirtyBitmap to be bad. Secondly it's | |
1000 | * absolutely possible, when we do migration with shared storage | |
1001 | * with dirty-bitmaps capability enabled: if the bitmap was loaded | |
1002 | * from this storage before migration start, the storage will | |
1003 | * of-course contain IN_USE outdated version of the bitmap, and we | |
1004 | * should not load it on migration target, as we already have this | |
1005 | * bitmap, being migrated. | |
1006 | */ | |
1007 | continue; | |
1008 | } | |
1009 | ||
1010 | bitmap = load_bitmap(bs, bm, errp); | |
74da6b94 JS |
1011 | if (bitmap == NULL) { |
1012 | goto fail; | |
1013 | } | |
a0319aac | 1014 | |
796a3798 | 1015 | bdrv_dirty_bitmap_set_persistence(bitmap, true); |
74da6b94 JS |
1016 | if (bm->flags & BME_FLAG_IN_USE) { |
1017 | bdrv_dirty_bitmap_set_inconsistent(bitmap); | |
1018 | } else { | |
1019 | /* NB: updated flags only get written if can_write(bs) is true. */ | |
d1258dd0 | 1020 | bm->flags |= BME_FLAG_IN_USE; |
74da6b94 | 1021 | needs_update = true; |
d1258dd0 | 1022 | } |
74da6b94 JS |
1023 | if (!(bm->flags & BME_FLAG_AUTO)) { |
1024 | bdrv_disable_dirty_bitmap(bitmap); | |
1025 | } | |
1026 | created_dirty_bitmaps = | |
1027 | g_slist_append(created_dirty_bitmaps, bitmap); | |
d1258dd0 VSO |
1028 | } |
1029 | ||
74da6b94 JS |
1030 | if (needs_update && can_write(bs)) { |
1031 | /* in_use flags must be updated */ | |
1032 | int ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
1033 | if (ret < 0) { | |
1034 | error_setg_errno(errp, -ret, "Can't update bitmap directory"); | |
1035 | goto fail; | |
d1258dd0 | 1036 | } |
74da6b94 JS |
1037 | header_updated = true; |
1038 | } | |
1039 | ||
1040 | if (!can_write(bs)) { | |
1041 | g_slist_foreach(created_dirty_bitmaps, set_readonly_helper, | |
1042 | (gpointer)true); | |
d1258dd0 VSO |
1043 | } |
1044 | ||
1045 | g_slist_free(created_dirty_bitmaps); | |
1046 | bitmap_list_free(bm_list); | |
1047 | ||
1048 | return header_updated; | |
1049 | ||
1050 | fail: | |
1051 | g_slist_foreach(created_dirty_bitmaps, release_dirty_bitmap_helper, bs); | |
1052 | g_slist_free(created_dirty_bitmaps); | |
1053 | bitmap_list_free(bm_list); | |
1054 | ||
1055 | return false; | |
1056 | } | |
1b6b0562 | 1057 | |
b8968c87 AS |
1058 | |
1059 | static Qcow2BitmapInfoFlagsList *get_bitmap_info_flags(uint32_t flags) | |
1060 | { | |
1061 | Qcow2BitmapInfoFlagsList *list = NULL; | |
1062 | Qcow2BitmapInfoFlagsList **plist = &list; | |
1063 | int i; | |
1064 | ||
1065 | static const struct { | |
1066 | int bme; /* Bitmap directory entry flags */ | |
1067 | int info; /* The flags to report to the user */ | |
1068 | } map[] = { | |
1069 | { BME_FLAG_IN_USE, QCOW2_BITMAP_INFO_FLAGS_IN_USE }, | |
1070 | { BME_FLAG_AUTO, QCOW2_BITMAP_INFO_FLAGS_AUTO }, | |
1071 | }; | |
1072 | ||
1073 | int map_size = ARRAY_SIZE(map); | |
1074 | ||
1075 | for (i = 0; i < map_size; ++i) { | |
1076 | if (flags & map[i].bme) { | |
1077 | Qcow2BitmapInfoFlagsList *entry = | |
1078 | g_new0(Qcow2BitmapInfoFlagsList, 1); | |
1079 | entry->value = map[i].info; | |
1080 | *plist = entry; | |
1081 | plist = &entry->next; | |
1082 | flags &= ~map[i].bme; | |
1083 | } | |
1084 | } | |
1085 | /* Check if the BME_* mapping above is complete */ | |
1086 | assert(!flags); | |
1087 | ||
1088 | return list; | |
1089 | } | |
1090 | ||
1091 | /* | |
1092 | * qcow2_get_bitmap_info_list() | |
1093 | * Returns a list of QCOW2 bitmap details. | |
1094 | * In case of no bitmaps, the function returns NULL and | |
1095 | * the @errp parameter is not set. | |
1096 | * When bitmap information can not be obtained, the function returns | |
1097 | * NULL and the @errp parameter is set. | |
1098 | */ | |
1099 | Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs, | |
1100 | Error **errp) | |
1101 | { | |
1102 | BDRVQcow2State *s = bs->opaque; | |
1103 | Qcow2BitmapList *bm_list; | |
1104 | Qcow2Bitmap *bm; | |
1105 | Qcow2BitmapInfoList *list = NULL; | |
1106 | Qcow2BitmapInfoList **plist = &list; | |
1107 | ||
1108 | if (s->nb_bitmaps == 0) { | |
1109 | return NULL; | |
1110 | } | |
1111 | ||
1112 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1113 | s->bitmap_directory_size, errp); | |
1114 | if (bm_list == NULL) { | |
1115 | return NULL; | |
1116 | } | |
1117 | ||
1118 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1119 | Qcow2BitmapInfo *info = g_new0(Qcow2BitmapInfo, 1); | |
1120 | Qcow2BitmapInfoList *obj = g_new0(Qcow2BitmapInfoList, 1); | |
1121 | info->granularity = 1U << bm->granularity_bits; | |
1122 | info->name = g_strdup(bm->name); | |
1123 | info->flags = get_bitmap_info_flags(bm->flags & ~BME_RESERVED_FLAGS); | |
1124 | obj->value = info; | |
1125 | *plist = obj; | |
1126 | plist = &obj->next; | |
1127 | } | |
1128 | ||
1129 | bitmap_list_free(bm_list); | |
1130 | ||
1131 | return list; | |
1132 | } | |
1133 | ||
bd429a88 | 1134 | int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp) |
1b6b0562 VSO |
1135 | { |
1136 | BDRVQcow2State *s = bs->opaque; | |
1137 | Qcow2BitmapList *bm_list; | |
1138 | Qcow2Bitmap *bm; | |
1139 | GSList *ro_dirty_bitmaps = NULL; | |
f6333cbf VSO |
1140 | int ret = -EINVAL; |
1141 | bool need_header_update = false; | |
1b6b0562 VSO |
1142 | |
1143 | if (s->nb_bitmaps == 0) { | |
1144 | /* No bitmaps - nothing to do */ | |
1145 | return 0; | |
1146 | } | |
1147 | ||
1b6b0562 VSO |
1148 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, |
1149 | s->bitmap_directory_size, errp); | |
1150 | if (bm_list == NULL) { | |
1151 | return -EINVAL; | |
1152 | } | |
1153 | ||
1154 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
74da6b94 | 1155 | BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name); |
1b6b0562 | 1156 | |
f6333cbf VSO |
1157 | if (!bitmap) { |
1158 | error_setg(errp, "Unexpected bitmap '%s' in image '%s'", | |
1159 | bm->name, bs->filename); | |
74da6b94 | 1160 | goto out; |
1b6b0562 | 1161 | } |
74da6b94 | 1162 | |
f6333cbf VSO |
1163 | if (!(bm->flags & BME_FLAG_IN_USE)) { |
1164 | if (!bdrv_dirty_bitmap_readonly(bitmap)) { | |
1165 | error_setg(errp, "Corruption: bitmap '%s' is not marked IN_USE " | |
1166 | "in the image '%s' and not marked readonly in RAM", | |
1167 | bm->name, bs->filename); | |
1168 | goto out; | |
1169 | } | |
1170 | if (bdrv_dirty_bitmap_inconsistent(bitmap)) { | |
1171 | error_setg(errp, "Corruption: bitmap '%s' is inconsistent but " | |
1172 | "is not marked IN_USE in the image '%s'", bm->name, | |
1173 | bs->filename); | |
1174 | goto out; | |
1175 | } | |
1176 | ||
1177 | bm->flags |= BME_FLAG_IN_USE; | |
1178 | need_header_update = true; | |
1179 | } else { | |
1180 | /* | |
1181 | * What if flags already has BME_FLAG_IN_USE ? | |
1182 | * | |
1183 | * 1. if we are reopening RW -> RW it's OK, of course. | |
1184 | * 2. if we are reopening RO -> RW: | |
1185 | * 2.1 if @bitmap is inconsistent, it's OK. It means that it was | |
1186 | * inconsistent (IN_USE) when we loaded it | |
1187 | * 2.2 if @bitmap is not inconsistent. This seems to be impossible | |
1188 | * and implies third party interaction. Let's error-out for | |
1189 | * safety. | |
1190 | */ | |
1191 | if (bdrv_dirty_bitmap_readonly(bitmap) && | |
1192 | !bdrv_dirty_bitmap_inconsistent(bitmap)) | |
1193 | { | |
1194 | error_setg(errp, "Corruption: bitmap '%s' is marked IN_USE " | |
1195 | "in the image '%s' but it is readonly and " | |
1196 | "consistent in RAM", | |
1197 | bm->name, bs->filename); | |
1198 | goto out; | |
1199 | } | |
1200 | } | |
1201 | ||
1202 | if (bdrv_dirty_bitmap_readonly(bitmap)) { | |
1203 | ro_dirty_bitmaps = g_slist_append(ro_dirty_bitmaps, bitmap); | |
1204 | } | |
1b6b0562 VSO |
1205 | } |
1206 | ||
f6333cbf VSO |
1207 | if (need_header_update) { |
1208 | if (!can_write(bs->file->bs) || !(bs->file->perm & BLK_PERM_WRITE)) { | |
1209 | error_setg(errp, "Failed to reopen bitmaps rw: no write access " | |
1210 | "the protocol file"); | |
1211 | goto out; | |
1212 | } | |
1213 | ||
1b6b0562 VSO |
1214 | /* in_use flags must be updated */ |
1215 | ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
1216 | if (ret < 0) { | |
f6333cbf | 1217 | error_setg_errno(errp, -ret, "Cannot update bitmap directory"); |
1b6b0562 VSO |
1218 | goto out; |
1219 | } | |
1b6b0562 VSO |
1220 | } |
1221 | ||
f6333cbf VSO |
1222 | g_slist_foreach(ro_dirty_bitmaps, set_readonly_helper, false); |
1223 | ret = 0; | |
1224 | ||
1b6b0562 VSO |
1225 | out: |
1226 | g_slist_free(ro_dirty_bitmaps); | |
1227 | bitmap_list_free(bm_list); | |
1228 | ||
1229 | return ret; | |
1230 | } | |
5f72826e | 1231 | |
d19c6b36 JS |
1232 | /* Checks to see if it's safe to resize bitmaps */ |
1233 | int qcow2_truncate_bitmaps_check(BlockDriverState *bs, Error **errp) | |
1234 | { | |
1235 | BDRVQcow2State *s = bs->opaque; | |
1236 | Qcow2BitmapList *bm_list; | |
1237 | Qcow2Bitmap *bm; | |
1238 | int ret = 0; | |
1239 | ||
1240 | if (s->nb_bitmaps == 0) { | |
1241 | return 0; | |
1242 | } | |
1243 | ||
1244 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1245 | s->bitmap_directory_size, errp); | |
1246 | if (bm_list == NULL) { | |
1247 | return -EINVAL; | |
1248 | } | |
1249 | ||
1250 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1251 | BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name); | |
1252 | if (bitmap == NULL) { | |
1253 | /* | |
1254 | * We rely on all bitmaps being in-memory to be able to resize them, | |
1255 | * Otherwise, we'd need to resize them on disk explicitly | |
1256 | */ | |
1257 | error_setg(errp, "Cannot resize qcow2 with persistent bitmaps that " | |
1258 | "were not loaded into memory"); | |
1259 | ret = -ENOTSUP; | |
1260 | goto out; | |
1261 | } | |
1262 | ||
1263 | /* | |
1264 | * The checks against readonly and busy are redundant, but certainly | |
1265 | * do no harm. checks against inconsistent are crucial: | |
1266 | */ | |
1267 | if (bdrv_dirty_bitmap_check(bitmap, BDRV_BITMAP_DEFAULT, errp)) { | |
1268 | ret = -ENOTSUP; | |
1269 | goto out; | |
1270 | } | |
1271 | } | |
1272 | ||
1273 | out: | |
1274 | bitmap_list_free(bm_list); | |
1275 | return ret; | |
1276 | } | |
1277 | ||
5f72826e VSO |
1278 | /* store_bitmap_data() |
1279 | * Store bitmap to image, filling bitmap table accordingly. | |
1280 | */ | |
1281 | static uint64_t *store_bitmap_data(BlockDriverState *bs, | |
1282 | BdrvDirtyBitmap *bitmap, | |
1283 | uint32_t *bitmap_table_size, Error **errp) | |
1284 | { | |
1285 | int ret; | |
1286 | BDRVQcow2State *s = bs->opaque; | |
49d741b5 EB |
1287 | int64_t offset; |
1288 | uint64_t limit; | |
5f72826e VSO |
1289 | uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); |
1290 | const char *bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1291 | uint8_t *buf = NULL; | |
1292 | BdrvDirtyBitmapIter *dbi; | |
1293 | uint64_t *tb; | |
1294 | uint64_t tb_size = | |
1295 | size_to_clusters(s, | |
86f6ae67 | 1296 | bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size)); |
5f72826e VSO |
1297 | |
1298 | if (tb_size > BME_MAX_TABLE_SIZE || | |
1299 | tb_size * s->cluster_size > BME_MAX_PHYS_SIZE) | |
1300 | { | |
1301 | error_setg(errp, "Bitmap '%s' is too big", bm_name); | |
1302 | return NULL; | |
1303 | } | |
1304 | ||
1305 | tb = g_try_new0(uint64_t, tb_size); | |
1306 | if (tb == NULL) { | |
1307 | error_setg(errp, "No memory"); | |
1308 | return NULL; | |
1309 | } | |
1310 | ||
715a74d8 | 1311 | dbi = bdrv_dirty_iter_new(bitmap); |
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 | |
49d741b5 EB |
1316 | while ((offset = bdrv_dirty_iter_next(dbi)) >= 0) { |
1317 | uint64_t cluster = offset / limit; | |
5f72826e VSO |
1318 | uint64_t end, write_size; |
1319 | int64_t off; | |
1320 | ||
49d741b5 EB |
1321 | /* |
1322 | * We found the first dirty offset, but want to write out the | |
1323 | * entire cluster of the bitmap that includes that offset, | |
1324 | * including any leading zero bits. | |
1325 | */ | |
1326 | offset = QEMU_ALIGN_DOWN(offset, limit); | |
1327 | end = MIN(bm_size, offset + limit); | |
1328 | write_size = bdrv_dirty_bitmap_serialization_size(bitmap, offset, | |
1329 | end - offset); | |
5f72826e VSO |
1330 | assert(write_size <= s->cluster_size); |
1331 | ||
1332 | off = qcow2_alloc_clusters(bs, s->cluster_size); | |
1333 | if (off < 0) { | |
1334 | error_setg_errno(errp, -off, | |
1335 | "Failed to allocate clusters for bitmap '%s'", | |
1336 | bm_name); | |
1337 | goto fail; | |
1338 | } | |
1339 | tb[cluster] = off; | |
1340 | ||
49d741b5 | 1341 | bdrv_dirty_bitmap_serialize_part(bitmap, buf, offset, end - offset); |
5f72826e VSO |
1342 | if (write_size < s->cluster_size) { |
1343 | memset(buf + write_size, 0, s->cluster_size - write_size); | |
1344 | } | |
1345 | ||
966b000f | 1346 | ret = qcow2_pre_write_overlap_check(bs, 0, off, s->cluster_size, false); |
5f72826e VSO |
1347 | if (ret < 0) { |
1348 | error_setg_errno(errp, -ret, "Qcow2 overlap check failed"); | |
1349 | goto fail; | |
1350 | } | |
1351 | ||
1352 | ret = bdrv_pwrite(bs->file, off, buf, s->cluster_size); | |
1353 | if (ret < 0) { | |
1354 | error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file", | |
1355 | bm_name); | |
1356 | goto fail; | |
1357 | } | |
1358 | ||
49d741b5 | 1359 | if (end >= bm_size) { |
5f72826e VSO |
1360 | break; |
1361 | } | |
1362 | ||
49d741b5 | 1363 | bdrv_set_dirty_iter(dbi, end); |
5f72826e VSO |
1364 | } |
1365 | ||
1366 | *bitmap_table_size = tb_size; | |
1367 | g_free(buf); | |
1368 | bdrv_dirty_iter_free(dbi); | |
1369 | ||
1370 | return tb; | |
1371 | ||
1372 | fail: | |
1373 | clear_bitmap_table(bs, tb, tb_size); | |
1374 | g_free(buf); | |
1375 | bdrv_dirty_iter_free(dbi); | |
1376 | g_free(tb); | |
1377 | ||
1378 | return NULL; | |
1379 | } | |
1380 | ||
1381 | /* store_bitmap() | |
1382 | * Store bm->dirty_bitmap to qcow2. | |
1383 | * Set bm->table_offset and bm->table_size accordingly. | |
1384 | */ | |
1385 | static int store_bitmap(BlockDriverState *bs, Qcow2Bitmap *bm, Error **errp) | |
1386 | { | |
1387 | int ret; | |
1388 | uint64_t *tb; | |
1389 | int64_t tb_offset; | |
1390 | uint32_t tb_size; | |
1391 | BdrvDirtyBitmap *bitmap = bm->dirty_bitmap; | |
1392 | const char *bm_name; | |
1393 | ||
1394 | assert(bitmap != NULL); | |
1395 | ||
1396 | bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1397 | ||
1398 | tb = store_bitmap_data(bs, bitmap, &tb_size, errp); | |
1399 | if (tb == NULL) { | |
1400 | return -EINVAL; | |
1401 | } | |
1402 | ||
1403 | assert(tb_size <= BME_MAX_TABLE_SIZE); | |
1404 | tb_offset = qcow2_alloc_clusters(bs, tb_size * sizeof(tb[0])); | |
1405 | if (tb_offset < 0) { | |
1406 | error_setg_errno(errp, -tb_offset, | |
1407 | "Failed to allocate clusters for bitmap '%s'", | |
1408 | bm_name); | |
1409 | ret = tb_offset; | |
1410 | goto fail; | |
1411 | } | |
1412 | ||
1413 | ret = qcow2_pre_write_overlap_check(bs, 0, tb_offset, | |
966b000f | 1414 | tb_size * sizeof(tb[0]), false); |
5f72826e VSO |
1415 | if (ret < 0) { |
1416 | error_setg_errno(errp, -ret, "Qcow2 overlap check failed"); | |
1417 | goto fail; | |
1418 | } | |
1419 | ||
1420 | bitmap_table_to_be(tb, tb_size); | |
1421 | ret = bdrv_pwrite(bs->file, tb_offset, tb, tb_size * sizeof(tb[0])); | |
1422 | if (ret < 0) { | |
1423 | error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file", | |
1424 | bm_name); | |
1425 | goto fail; | |
1426 | } | |
1427 | ||
1428 | g_free(tb); | |
1429 | ||
1430 | bm->table.offset = tb_offset; | |
1431 | bm->table.size = tb_size; | |
1432 | ||
1433 | return 0; | |
1434 | ||
1435 | fail: | |
1436 | clear_bitmap_table(bs, tb, tb_size); | |
1437 | ||
1438 | if (tb_offset > 0) { | |
1439 | qcow2_free_clusters(bs, tb_offset, tb_size * sizeof(tb[0]), | |
1440 | QCOW2_DISCARD_OTHER); | |
1441 | } | |
1442 | ||
1443 | g_free(tb); | |
1444 | ||
1445 | return ret; | |
1446 | } | |
1447 | ||
1448 | static Qcow2Bitmap *find_bitmap_by_name(Qcow2BitmapList *bm_list, | |
1449 | const char *name) | |
1450 | { | |
1451 | Qcow2Bitmap *bm; | |
1452 | ||
1453 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1454 | if (strcmp(name, bm->name) == 0) { | |
1455 | return bm; | |
1456 | } | |
1457 | } | |
1458 | ||
1459 | return NULL; | |
1460 | } | |
1461 | ||
d2c3080e VSO |
1462 | int coroutine_fn qcow2_co_remove_persistent_dirty_bitmap(BlockDriverState *bs, |
1463 | const char *name, | |
1464 | Error **errp) | |
469c71ed VSO |
1465 | { |
1466 | int ret; | |
1467 | BDRVQcow2State *s = bs->opaque; | |
d2c3080e | 1468 | Qcow2Bitmap *bm = NULL; |
469c71ed VSO |
1469 | Qcow2BitmapList *bm_list; |
1470 | ||
1471 | if (s->nb_bitmaps == 0) { | |
f56281ab VSO |
1472 | /* |
1473 | * Absence of the bitmap is not an error: see explanation above | |
1474 | * bdrv_co_remove_persistent_dirty_bitmap() definition. | |
1475 | */ | |
b56a1e31 | 1476 | return 0; |
469c71ed VSO |
1477 | } |
1478 | ||
d2c3080e VSO |
1479 | qemu_co_mutex_lock(&s->lock); |
1480 | ||
469c71ed VSO |
1481 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, |
1482 | s->bitmap_directory_size, errp); | |
1483 | if (bm_list == NULL) { | |
d2c3080e VSO |
1484 | ret = -EIO; |
1485 | goto out; | |
469c71ed VSO |
1486 | } |
1487 | ||
1488 | bm = find_bitmap_by_name(bm_list, name); | |
1489 | if (bm == NULL) { | |
f56281ab VSO |
1490 | /* Absence of the bitmap is not an error, see above. */ |
1491 | ret = 0; | |
b56a1e31 | 1492 | goto out; |
469c71ed VSO |
1493 | } |
1494 | ||
1495 | QSIMPLEQ_REMOVE(bm_list, bm, Qcow2Bitmap, entry); | |
1496 | ||
1497 | ret = update_ext_header_and_dir(bs, bm_list); | |
1498 | if (ret < 0) { | |
1499 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
b56a1e31 | 1500 | goto out; |
469c71ed VSO |
1501 | } |
1502 | ||
1503 | free_bitmap_clusters(bs, &bm->table); | |
1504 | ||
b56a1e31 | 1505 | out: |
d2c3080e VSO |
1506 | qemu_co_mutex_unlock(&s->lock); |
1507 | ||
469c71ed VSO |
1508 | bitmap_free(bm); |
1509 | bitmap_list_free(bm_list); | |
b56a1e31 VSO |
1510 | |
1511 | return ret; | |
469c71ed VSO |
1512 | } |
1513 | ||
644ddbb7 VSO |
1514 | /* |
1515 | * qcow2_store_persistent_dirty_bitmaps | |
1516 | * | |
1517 | * Stores persistent BdrvDirtyBitmap objects. | |
1518 | * | |
1519 | * @release_stored: if true, release BdrvDirtyBitmap's after storing to the | |
1520 | * image. This is used in two cases, both via qcow2_inactivate: | |
1521 | * 1. bdrv_close: It's correct to remove bitmaps on close. | |
1522 | * 2. migration: If bitmaps are migrated through migration channel via | |
1523 | * 'dirty-bitmaps' migration capability they are not handled by this code. | |
1524 | * Otherwise, it's OK to drop BdrvDirtyBitmap's and reload them on | |
1525 | * invalidation. | |
1526 | * | |
1527 | * Anyway, it's correct to remove BdrvDirtyBitmap's on inactivation, as | |
1528 | * inactivation means that we lose control on disk, and therefore on bitmaps, | |
1529 | * we should sync them and do not touch more. | |
1530 | * | |
1531 | * Contrariwise, we don't want to release any bitmaps on just reopen-to-ro, | |
1532 | * when we need to store them, as image is still under our control, and it's | |
1533 | * good to keep all the bitmaps in read-only mode. Moreover, keeping them | |
1534 | * read-only is correct because this is what would happen if we opened the node | |
1535 | * readonly to begin with, and whether we opened directly or reopened to that | |
1536 | * state shouldn't matter for the state we get afterward. | |
1537 | */ | |
1538 | void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, | |
1539 | bool release_stored, Error **errp) | |
5f72826e VSO |
1540 | { |
1541 | BdrvDirtyBitmap *bitmap; | |
1542 | BDRVQcow2State *s = bs->opaque; | |
1543 | uint32_t new_nb_bitmaps = s->nb_bitmaps; | |
1544 | uint64_t new_dir_size = s->bitmap_directory_size; | |
1545 | int ret; | |
1546 | Qcow2BitmapList *bm_list; | |
1547 | Qcow2Bitmap *bm; | |
b58deb34 | 1548 | QSIMPLEQ_HEAD(, Qcow2BitmapTable) drop_tables; |
5f72826e | 1549 | Qcow2BitmapTable *tb, *tb_next; |
f88676c1 | 1550 | bool need_write = false; |
5f72826e VSO |
1551 | |
1552 | QSIMPLEQ_INIT(&drop_tables); | |
1553 | ||
1554 | if (s->nb_bitmaps == 0) { | |
1555 | bm_list = bitmap_list_new(); | |
1556 | } else { | |
1557 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1558 | s->bitmap_directory_size, errp); | |
1559 | if (bm_list == NULL) { | |
1560 | return; | |
1561 | } | |
1562 | } | |
1563 | ||
1564 | /* check constraints and names */ | |
ef9041a7 | 1565 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
5f72826e VSO |
1566 | const char *name = bdrv_dirty_bitmap_name(bitmap); |
1567 | uint32_t granularity = bdrv_dirty_bitmap_granularity(bitmap); | |
1568 | Qcow2Bitmap *bm; | |
1569 | ||
796a3798 | 1570 | if (!bdrv_dirty_bitmap_get_persistence(bitmap) || |
74da6b94 JS |
1571 | bdrv_dirty_bitmap_readonly(bitmap) || |
1572 | bdrv_dirty_bitmap_inconsistent(bitmap)) { | |
5f72826e VSO |
1573 | continue; |
1574 | } | |
1575 | ||
f88676c1 VSO |
1576 | need_write = true; |
1577 | ||
5f72826e VSO |
1578 | if (check_constraints_on_bitmap(bs, name, granularity, errp) < 0) { |
1579 | error_prepend(errp, "Bitmap '%s' doesn't satisfy the constraints: ", | |
1580 | name); | |
1581 | goto fail; | |
1582 | } | |
1583 | ||
1584 | bm = find_bitmap_by_name(bm_list, name); | |
1585 | if (bm == NULL) { | |
1586 | if (++new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
1587 | error_setg(errp, "Too many persistent bitmaps"); | |
1588 | goto fail; | |
1589 | } | |
1590 | ||
1591 | new_dir_size += calc_dir_entry_size(strlen(name), 0); | |
1592 | if (new_dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
1593 | error_setg(errp, "Bitmap directory is too large"); | |
1594 | goto fail; | |
1595 | } | |
1596 | ||
1597 | bm = g_new0(Qcow2Bitmap, 1); | |
1598 | bm->name = g_strdup(name); | |
1599 | QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry); | |
1600 | } else { | |
1601 | if (!(bm->flags & BME_FLAG_IN_USE)) { | |
1602 | error_setg(errp, "Bitmap '%s' already exists in the image", | |
1603 | name); | |
1604 | goto fail; | |
1605 | } | |
1606 | tb = g_memdup(&bm->table, sizeof(bm->table)); | |
1607 | bm->table.offset = 0; | |
1608 | bm->table.size = 0; | |
1609 | QSIMPLEQ_INSERT_TAIL(&drop_tables, tb, entry); | |
1610 | } | |
3e99da5e | 1611 | bm->flags = bdrv_dirty_bitmap_enabled(bitmap) ? BME_FLAG_AUTO : 0; |
5f72826e VSO |
1612 | bm->granularity_bits = ctz32(bdrv_dirty_bitmap_granularity(bitmap)); |
1613 | bm->dirty_bitmap = bitmap; | |
1614 | } | |
1615 | ||
f88676c1 VSO |
1616 | if (!need_write) { |
1617 | goto success; | |
1618 | } | |
1619 | ||
1620 | if (!can_write(bs)) { | |
1621 | error_setg(errp, "No write access"); | |
1622 | goto fail; | |
1623 | } | |
1624 | ||
5f72826e VSO |
1625 | /* allocate clusters and store bitmaps */ |
1626 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1627 | if (bm->dirty_bitmap == NULL) { | |
1628 | continue; | |
1629 | } | |
1630 | ||
1631 | ret = store_bitmap(bs, bm, errp); | |
1632 | if (ret < 0) { | |
1633 | goto fail; | |
1634 | } | |
1635 | } | |
1636 | ||
1637 | ret = update_ext_header_and_dir(bs, bm_list); | |
1638 | if (ret < 0) { | |
1639 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
1640 | goto fail; | |
1641 | } | |
1642 | ||
1643 | /* Bitmap directory was successfully updated, so, old data can be dropped. | |
1644 | * TODO it is better to reuse these clusters */ | |
1645 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1646 | free_bitmap_clusters(bs, tb); | |
1647 | g_free(tb); | |
1648 | } | |
1649 | ||
644ddbb7 VSO |
1650 | if (release_stored) { |
1651 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1652 | if (bm->dirty_bitmap == NULL) { | |
1653 | continue; | |
1654 | } | |
9c98f145 | 1655 | |
644ddbb7 VSO |
1656 | bdrv_release_dirty_bitmap(bm->dirty_bitmap); |
1657 | } | |
9c98f145 VSO |
1658 | } |
1659 | ||
f88676c1 | 1660 | success: |
5f72826e VSO |
1661 | bitmap_list_free(bm_list); |
1662 | return; | |
1663 | ||
1664 | fail: | |
1665 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1666 | if (bm->dirty_bitmap == NULL || bm->table.offset == 0) { | |
1667 | continue; | |
1668 | } | |
1669 | ||
1670 | free_bitmap_clusters(bs, &bm->table); | |
1671 | } | |
1672 | ||
1673 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1674 | g_free(tb); | |
1675 | } | |
1676 | ||
1677 | bitmap_list_free(bm_list); | |
1678 | } | |
169b8793 VSO |
1679 | |
1680 | int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp) | |
1681 | { | |
1682 | BdrvDirtyBitmap *bitmap; | |
1683 | Error *local_err = NULL; | |
1684 | ||
644ddbb7 | 1685 | qcow2_store_persistent_dirty_bitmaps(bs, false, &local_err); |
169b8793 VSO |
1686 | if (local_err != NULL) { |
1687 | error_propagate(errp, local_err); | |
1688 | return -EINVAL; | |
1689 | } | |
1690 | ||
ef9041a7 | 1691 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
796a3798 | 1692 | if (bdrv_dirty_bitmap_get_persistence(bitmap)) { |
169b8793 VSO |
1693 | bdrv_dirty_bitmap_set_readonly(bitmap, true); |
1694 | } | |
1695 | } | |
1696 | ||
1697 | return 0; | |
1698 | } | |
da0eb242 | 1699 | |
d2c3080e VSO |
1700 | bool coroutine_fn qcow2_co_can_store_new_dirty_bitmap(BlockDriverState *bs, |
1701 | const char *name, | |
1702 | uint32_t granularity, | |
1703 | Error **errp) | |
da0eb242 VSO |
1704 | { |
1705 | BDRVQcow2State *s = bs->opaque; | |
a1db8733 VSO |
1706 | BdrvDirtyBitmap *bitmap; |
1707 | uint64_t bitmap_directory_size = 0; | |
1708 | uint32_t nb_bitmaps = 0; | |
1709 | ||
1710 | if (bdrv_find_dirty_bitmap(bs, name)) { | |
1711 | error_setg(errp, "Bitmap already exists: %s", name); | |
1712 | return false; | |
1713 | } | |
da0eb242 | 1714 | |
c9ceb3ec HR |
1715 | if (s->qcow_version < 3) { |
1716 | /* Without autoclear_features, we would always have to assume | |
1717 | * that a program without persistent dirty bitmap support has | |
1718 | * accessed this qcow2 file when opening it, and would thus | |
1719 | * have to drop all dirty bitmaps (defeating their purpose). | |
1720 | */ | |
1721 | error_setg(errp, "Cannot store dirty bitmaps in qcow2 v2 files"); | |
1722 | goto fail; | |
1723 | } | |
1724 | ||
da0eb242 VSO |
1725 | if (check_constraints_on_bitmap(bs, name, granularity, errp) != 0) { |
1726 | goto fail; | |
1727 | } | |
1728 | ||
a1db8733 VSO |
1729 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
1730 | if (bdrv_dirty_bitmap_get_persistence(bitmap)) { | |
1731 | nb_bitmaps++; | |
1732 | bitmap_directory_size += | |
1733 | calc_dir_entry_size(strlen(bdrv_dirty_bitmap_name(bitmap)), 0); | |
1734 | } | |
da0eb242 | 1735 | } |
a1db8733 VSO |
1736 | nb_bitmaps++; |
1737 | bitmap_directory_size += calc_dir_entry_size(strlen(name), 0); | |
da0eb242 | 1738 | |
a1db8733 | 1739 | if (nb_bitmaps > QCOW2_MAX_BITMAPS) { |
da0eb242 VSO |
1740 | error_setg(errp, |
1741 | "Maximum number of persistent bitmaps is already reached"); | |
1742 | goto fail; | |
1743 | } | |
1744 | ||
a1db8733 | 1745 | if (bitmap_directory_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { |
da0eb242 VSO |
1746 | error_setg(errp, "Not enough space in the bitmap directory"); |
1747 | goto fail; | |
1748 | } | |
1749 | ||
da0eb242 VSO |
1750 | return true; |
1751 | ||
1752 | fail: | |
1753 | error_prepend(errp, "Can't make bitmap '%s' persistent in '%s': ", | |
1754 | name, bdrv_get_device_or_node_name(bs)); | |
1755 | return false; | |
1756 | } |