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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: | |
88ddffae VSO |
650 | error_setg(errp, "Broken bitmap directory"); |
651 | ||
652 | fail: | |
653 | g_free(dir); | |
654 | bitmap_list_free(bm_list); | |
655 | ||
656 | return NULL; | |
657 | } | |
658 | ||
659 | int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, | |
660 | void **refcount_table, | |
661 | int64_t *refcount_table_size) | |
662 | { | |
663 | int ret; | |
664 | BDRVQcow2State *s = bs->opaque; | |
665 | Qcow2BitmapList *bm_list; | |
666 | Qcow2Bitmap *bm; | |
667 | ||
668 | if (s->nb_bitmaps == 0) { | |
669 | return 0; | |
670 | } | |
671 | ||
672 | ret = qcow2_inc_refcounts_imrt(bs, res, refcount_table, refcount_table_size, | |
673 | s->bitmap_directory_offset, | |
674 | s->bitmap_directory_size); | |
675 | if (ret < 0) { | |
676 | return ret; | |
677 | } | |
678 | ||
679 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
680 | s->bitmap_directory_size, NULL); | |
681 | if (bm_list == NULL) { | |
682 | res->corruptions++; | |
683 | return -EINVAL; | |
684 | } | |
685 | ||
686 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
687 | uint64_t *bitmap_table = NULL; | |
688 | int i; | |
689 | ||
690 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
691 | refcount_table, refcount_table_size, | |
692 | bm->table.offset, | |
693 | bm->table.size * sizeof(uint64_t)); | |
694 | if (ret < 0) { | |
695 | goto out; | |
696 | } | |
697 | ||
698 | ret = bitmap_table_load(bs, &bm->table, &bitmap_table); | |
699 | if (ret < 0) { | |
700 | res->corruptions++; | |
701 | goto out; | |
702 | } | |
703 | ||
704 | for (i = 0; i < bm->table.size; ++i) { | |
705 | uint64_t entry = bitmap_table[i]; | |
706 | uint64_t offset = entry & BME_TABLE_ENTRY_OFFSET_MASK; | |
707 | ||
708 | if (check_table_entry(entry, s->cluster_size) < 0) { | |
709 | res->corruptions++; | |
710 | continue; | |
711 | } | |
712 | ||
713 | if (offset == 0) { | |
714 | continue; | |
715 | } | |
716 | ||
717 | ret = qcow2_inc_refcounts_imrt(bs, res, | |
718 | refcount_table, refcount_table_size, | |
719 | offset, s->cluster_size); | |
720 | if (ret < 0) { | |
721 | g_free(bitmap_table); | |
722 | goto out; | |
723 | } | |
724 | } | |
725 | ||
726 | g_free(bitmap_table); | |
727 | } | |
728 | ||
729 | out: | |
730 | bitmap_list_free(bm_list); | |
731 | ||
732 | return ret; | |
733 | } | |
d1258dd0 VSO |
734 | |
735 | /* bitmap_list_store | |
736 | * Store bitmap list to qcow2 image as a bitmap directory. | |
737 | * Everything is checked. | |
738 | */ | |
739 | static int bitmap_list_store(BlockDriverState *bs, Qcow2BitmapList *bm_list, | |
740 | uint64_t *offset, uint64_t *size, bool in_place) | |
741 | { | |
742 | int ret; | |
743 | uint8_t *dir; | |
744 | int64_t dir_offset = 0; | |
745 | uint64_t dir_size = 0; | |
746 | Qcow2Bitmap *bm; | |
747 | Qcow2BitmapDirEntry *e; | |
748 | ||
749 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
750 | dir_size += calc_dir_entry_size(strlen(bm->name), 0); | |
751 | } | |
752 | ||
753 | if (dir_size == 0 || dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
754 | return -EINVAL; | |
755 | } | |
756 | ||
757 | if (in_place) { | |
758 | if (*size != dir_size || *offset == 0) { | |
759 | return -EINVAL; | |
760 | } | |
761 | ||
762 | dir_offset = *offset; | |
763 | } | |
764 | ||
6388903e | 765 | dir = g_try_malloc0(dir_size); |
d1258dd0 VSO |
766 | if (dir == NULL) { |
767 | return -ENOMEM; | |
768 | } | |
769 | ||
770 | e = (Qcow2BitmapDirEntry *)dir; | |
771 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
772 | e->bitmap_table_offset = bm->table.offset; | |
773 | e->bitmap_table_size = bm->table.size; | |
774 | e->flags = bm->flags; | |
775 | e->type = BT_DIRTY_TRACKING_BITMAP; | |
776 | e->granularity_bits = bm->granularity_bits; | |
777 | e->name_size = strlen(bm->name); | |
778 | e->extra_data_size = 0; | |
779 | memcpy(e + 1, bm->name, e->name_size); | |
780 | ||
781 | if (check_dir_entry(bs, e) < 0) { | |
782 | ret = -EINVAL; | |
783 | goto fail; | |
784 | } | |
785 | ||
786 | e = next_dir_entry(e); | |
787 | } | |
788 | ||
789 | bitmap_directory_to_be(dir, dir_size); | |
790 | ||
791 | if (!in_place) { | |
792 | dir_offset = qcow2_alloc_clusters(bs, dir_size); | |
793 | if (dir_offset < 0) { | |
794 | ret = dir_offset; | |
795 | goto fail; | |
796 | } | |
797 | } | |
798 | ||
0e4e4318 VSO |
799 | /* Actually, even in in-place case ignoring QCOW2_OL_BITMAP_DIRECTORY is not |
800 | * necessary, because we drop QCOW2_AUTOCLEAR_BITMAPS when updating bitmap | |
801 | * directory in-place (actually, turn-off the extension), which is checked | |
802 | * in qcow2_check_metadata_overlap() */ | |
803 | ret = qcow2_pre_write_overlap_check( | |
966b000f KW |
804 | bs, in_place ? QCOW2_OL_BITMAP_DIRECTORY : 0, dir_offset, dir_size, |
805 | false); | |
d1258dd0 VSO |
806 | if (ret < 0) { |
807 | goto fail; | |
808 | } | |
809 | ||
810 | ret = bdrv_pwrite(bs->file, dir_offset, dir, dir_size); | |
811 | if (ret < 0) { | |
812 | goto fail; | |
813 | } | |
814 | ||
815 | g_free(dir); | |
816 | ||
817 | if (!in_place) { | |
818 | *size = dir_size; | |
819 | *offset = dir_offset; | |
820 | } | |
821 | ||
822 | return 0; | |
823 | ||
824 | fail: | |
825 | g_free(dir); | |
826 | ||
827 | if (!in_place && dir_offset > 0) { | |
828 | qcow2_free_clusters(bs, dir_offset, dir_size, QCOW2_DISCARD_OTHER); | |
829 | } | |
830 | ||
831 | return ret; | |
832 | } | |
833 | ||
834 | /* | |
835 | * Bitmap List end | |
836 | */ | |
837 | ||
838 | static int update_ext_header_and_dir_in_place(BlockDriverState *bs, | |
839 | Qcow2BitmapList *bm_list) | |
840 | { | |
841 | BDRVQcow2State *s = bs->opaque; | |
842 | int ret; | |
843 | ||
844 | if (!(s->autoclear_features & QCOW2_AUTOCLEAR_BITMAPS) || | |
845 | bm_list == NULL || QSIMPLEQ_EMPTY(bm_list) || | |
846 | bitmap_list_count(bm_list) != s->nb_bitmaps) | |
847 | { | |
848 | return -EINVAL; | |
849 | } | |
850 | ||
851 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
852 | ret = update_header_sync(bs); | |
853 | if (ret < 0) { | |
854 | /* Two variants are possible here: | |
855 | * 1. Autoclear flag is dropped, all bitmaps will be lost. | |
856 | * 2. Autoclear flag is not dropped, old state is left. | |
857 | */ | |
858 | return ret; | |
859 | } | |
860 | ||
861 | /* autoclear bit is not set, so we can safely update bitmap directory */ | |
862 | ||
863 | ret = bitmap_list_store(bs, bm_list, &s->bitmap_directory_offset, | |
864 | &s->bitmap_directory_size, true); | |
865 | if (ret < 0) { | |
866 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
867 | * qemu-img check */ | |
868 | return ret; | |
869 | } | |
870 | ||
871 | ret = update_header_sync(bs); | |
872 | if (ret < 0) { | |
873 | /* autoclear bit is cleared, so all leaked clusters would be removed on | |
874 | * qemu-img check */ | |
875 | return ret; | |
876 | } | |
877 | ||
878 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
879 | return update_header_sync(bs); | |
880 | /* If final update_header_sync() fails, two variants are possible: | |
881 | * 1. Autoclear flag is not set, all bitmaps will be lost. | |
882 | * 2. Autoclear flag is set, header and directory are successfully updated. | |
883 | */ | |
884 | } | |
885 | ||
5f72826e VSO |
886 | static int update_ext_header_and_dir(BlockDriverState *bs, |
887 | Qcow2BitmapList *bm_list) | |
888 | { | |
889 | BDRVQcow2State *s = bs->opaque; | |
890 | int ret; | |
891 | uint64_t new_offset = 0; | |
892 | uint64_t new_size = 0; | |
893 | uint32_t new_nb_bitmaps = 0; | |
894 | uint64_t old_offset = s->bitmap_directory_offset; | |
895 | uint64_t old_size = s->bitmap_directory_size; | |
896 | uint32_t old_nb_bitmaps = s->nb_bitmaps; | |
897 | uint64_t old_autocl = s->autoclear_features; | |
898 | ||
899 | if (bm_list != NULL && !QSIMPLEQ_EMPTY(bm_list)) { | |
900 | new_nb_bitmaps = bitmap_list_count(bm_list); | |
901 | ||
902 | if (new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
903 | return -EINVAL; | |
904 | } | |
905 | ||
906 | ret = bitmap_list_store(bs, bm_list, &new_offset, &new_size, false); | |
907 | if (ret < 0) { | |
908 | return ret; | |
909 | } | |
910 | ||
1a0c2bfb | 911 | ret = qcow2_flush_caches(bs); |
5f72826e VSO |
912 | if (ret < 0) { |
913 | goto fail; | |
914 | } | |
915 | ||
916 | s->autoclear_features |= QCOW2_AUTOCLEAR_BITMAPS; | |
917 | } else { | |
918 | s->autoclear_features &= ~(uint64_t)QCOW2_AUTOCLEAR_BITMAPS; | |
919 | } | |
920 | ||
921 | s->bitmap_directory_offset = new_offset; | |
922 | s->bitmap_directory_size = new_size; | |
923 | s->nb_bitmaps = new_nb_bitmaps; | |
924 | ||
925 | ret = update_header_sync(bs); | |
926 | if (ret < 0) { | |
927 | goto fail; | |
928 | } | |
929 | ||
930 | if (old_size > 0) { | |
931 | qcow2_free_clusters(bs, old_offset, old_size, QCOW2_DISCARD_OTHER); | |
932 | } | |
933 | ||
934 | return 0; | |
935 | ||
936 | fail: | |
937 | if (new_offset > 0) { | |
938 | qcow2_free_clusters(bs, new_offset, new_size, QCOW2_DISCARD_OTHER); | |
939 | } | |
940 | ||
941 | s->bitmap_directory_offset = old_offset; | |
942 | s->bitmap_directory_size = old_size; | |
943 | s->nb_bitmaps = old_nb_bitmaps; | |
944 | s->autoclear_features = old_autocl; | |
945 | ||
946 | return ret; | |
947 | } | |
948 | ||
d1258dd0 VSO |
949 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ |
950 | static void release_dirty_bitmap_helper(gpointer bitmap, | |
951 | gpointer bs) | |
952 | { | |
5deb6cbd | 953 | bdrv_release_dirty_bitmap(bitmap); |
d1258dd0 VSO |
954 | } |
955 | ||
956 | /* for g_slist_foreach for GSList of BdrvDirtyBitmap* elements */ | |
957 | static void set_readonly_helper(gpointer bitmap, gpointer value) | |
958 | { | |
959 | bdrv_dirty_bitmap_set_readonly(bitmap, (bool)value); | |
960 | } | |
961 | ||
3e99da5e | 962 | /* qcow2_load_dirty_bitmaps() |
d1258dd0 VSO |
963 | * Return value is a hint for caller: true means that the Qcow2 header was |
964 | * updated. (false doesn't mean that the header should be updated by the | |
965 | * caller, it just means that updating was not needed or the image cannot be | |
966 | * written to). | |
967 | * On failure the function returns false. | |
968 | */ | |
3e99da5e | 969 | bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) |
d1258dd0 VSO |
970 | { |
971 | BDRVQcow2State *s = bs->opaque; | |
972 | Qcow2BitmapList *bm_list; | |
973 | Qcow2Bitmap *bm; | |
974 | GSList *created_dirty_bitmaps = NULL; | |
975 | bool header_updated = false; | |
74da6b94 | 976 | bool needs_update = false; |
d1258dd0 VSO |
977 | |
978 | if (s->nb_bitmaps == 0) { | |
979 | /* No bitmaps - nothing to do */ | |
980 | return false; | |
981 | } | |
982 | ||
983 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
984 | s->bitmap_directory_size, errp); | |
985 | if (bm_list == NULL) { | |
986 | return false; | |
987 | } | |
988 | ||
989 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
a505475b VSO |
990 | BdrvDirtyBitmap *bitmap; |
991 | ||
992 | if ((bm->flags & BME_FLAG_IN_USE) && | |
993 | bdrv_find_dirty_bitmap(bs, bm->name)) | |
994 | { | |
995 | /* | |
996 | * We already have corresponding BdrvDirtyBitmap, and bitmap in the | |
997 | * image is marked IN_USE. Firstly, this state is valid, no reason | |
998 | * to consider existing BdrvDirtyBitmap to be bad. Secondly it's | |
999 | * absolutely possible, when we do migration with shared storage | |
1000 | * with dirty-bitmaps capability enabled: if the bitmap was loaded | |
1001 | * from this storage before migration start, the storage will | |
1002 | * of-course contain IN_USE outdated version of the bitmap, and we | |
1003 | * should not load it on migration target, as we already have this | |
1004 | * bitmap, being migrated. | |
1005 | */ | |
1006 | continue; | |
1007 | } | |
1008 | ||
1009 | bitmap = load_bitmap(bs, bm, errp); | |
74da6b94 JS |
1010 | if (bitmap == NULL) { |
1011 | goto fail; | |
1012 | } | |
a0319aac | 1013 | |
796a3798 | 1014 | bdrv_dirty_bitmap_set_persistence(bitmap, true); |
74da6b94 JS |
1015 | if (bm->flags & BME_FLAG_IN_USE) { |
1016 | bdrv_dirty_bitmap_set_inconsistent(bitmap); | |
1017 | } else { | |
1018 | /* NB: updated flags only get written if can_write(bs) is true. */ | |
d1258dd0 | 1019 | bm->flags |= BME_FLAG_IN_USE; |
74da6b94 | 1020 | needs_update = true; |
d1258dd0 | 1021 | } |
74da6b94 JS |
1022 | if (!(bm->flags & BME_FLAG_AUTO)) { |
1023 | bdrv_disable_dirty_bitmap(bitmap); | |
1024 | } | |
1025 | created_dirty_bitmaps = | |
1026 | g_slist_append(created_dirty_bitmaps, bitmap); | |
d1258dd0 VSO |
1027 | } |
1028 | ||
74da6b94 JS |
1029 | if (needs_update && can_write(bs)) { |
1030 | /* in_use flags must be updated */ | |
1031 | int ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
1032 | if (ret < 0) { | |
1033 | error_setg_errno(errp, -ret, "Can't update bitmap directory"); | |
1034 | goto fail; | |
d1258dd0 | 1035 | } |
74da6b94 JS |
1036 | header_updated = true; |
1037 | } | |
1038 | ||
1039 | if (!can_write(bs)) { | |
1040 | g_slist_foreach(created_dirty_bitmaps, set_readonly_helper, | |
1041 | (gpointer)true); | |
d1258dd0 VSO |
1042 | } |
1043 | ||
1044 | g_slist_free(created_dirty_bitmaps); | |
1045 | bitmap_list_free(bm_list); | |
1046 | ||
1047 | return header_updated; | |
1048 | ||
1049 | fail: | |
1050 | g_slist_foreach(created_dirty_bitmaps, release_dirty_bitmap_helper, bs); | |
1051 | g_slist_free(created_dirty_bitmaps); | |
1052 | bitmap_list_free(bm_list); | |
1053 | ||
1054 | return false; | |
1055 | } | |
1b6b0562 | 1056 | |
b8968c87 AS |
1057 | |
1058 | static Qcow2BitmapInfoFlagsList *get_bitmap_info_flags(uint32_t flags) | |
1059 | { | |
1060 | Qcow2BitmapInfoFlagsList *list = NULL; | |
1061 | Qcow2BitmapInfoFlagsList **plist = &list; | |
1062 | int i; | |
1063 | ||
1064 | static const struct { | |
1065 | int bme; /* Bitmap directory entry flags */ | |
1066 | int info; /* The flags to report to the user */ | |
1067 | } map[] = { | |
1068 | { BME_FLAG_IN_USE, QCOW2_BITMAP_INFO_FLAGS_IN_USE }, | |
1069 | { BME_FLAG_AUTO, QCOW2_BITMAP_INFO_FLAGS_AUTO }, | |
1070 | }; | |
1071 | ||
1072 | int map_size = ARRAY_SIZE(map); | |
1073 | ||
1074 | for (i = 0; i < map_size; ++i) { | |
1075 | if (flags & map[i].bme) { | |
1076 | Qcow2BitmapInfoFlagsList *entry = | |
1077 | g_new0(Qcow2BitmapInfoFlagsList, 1); | |
1078 | entry->value = map[i].info; | |
1079 | *plist = entry; | |
1080 | plist = &entry->next; | |
1081 | flags &= ~map[i].bme; | |
1082 | } | |
1083 | } | |
1084 | /* Check if the BME_* mapping above is complete */ | |
1085 | assert(!flags); | |
1086 | ||
1087 | return list; | |
1088 | } | |
1089 | ||
1090 | /* | |
1091 | * qcow2_get_bitmap_info_list() | |
1092 | * Returns a list of QCOW2 bitmap details. | |
1093 | * In case of no bitmaps, the function returns NULL and | |
1094 | * the @errp parameter is not set. | |
1095 | * When bitmap information can not be obtained, the function returns | |
1096 | * NULL and the @errp parameter is set. | |
1097 | */ | |
1098 | Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs, | |
1099 | Error **errp) | |
1100 | { | |
1101 | BDRVQcow2State *s = bs->opaque; | |
1102 | Qcow2BitmapList *bm_list; | |
1103 | Qcow2Bitmap *bm; | |
1104 | Qcow2BitmapInfoList *list = NULL; | |
1105 | Qcow2BitmapInfoList **plist = &list; | |
1106 | ||
1107 | if (s->nb_bitmaps == 0) { | |
1108 | return NULL; | |
1109 | } | |
1110 | ||
1111 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1112 | s->bitmap_directory_size, errp); | |
1113 | if (bm_list == NULL) { | |
1114 | return NULL; | |
1115 | } | |
1116 | ||
1117 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1118 | Qcow2BitmapInfo *info = g_new0(Qcow2BitmapInfo, 1); | |
1119 | Qcow2BitmapInfoList *obj = g_new0(Qcow2BitmapInfoList, 1); | |
1120 | info->granularity = 1U << bm->granularity_bits; | |
1121 | info->name = g_strdup(bm->name); | |
1122 | info->flags = get_bitmap_info_flags(bm->flags & ~BME_RESERVED_FLAGS); | |
1123 | obj->value = info; | |
1124 | *plist = obj; | |
1125 | plist = &obj->next; | |
1126 | } | |
1127 | ||
1128 | bitmap_list_free(bm_list); | |
1129 | ||
1130 | return list; | |
1131 | } | |
1132 | ||
bd429a88 | 1133 | int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp) |
1b6b0562 VSO |
1134 | { |
1135 | BDRVQcow2State *s = bs->opaque; | |
1136 | Qcow2BitmapList *bm_list; | |
1137 | Qcow2Bitmap *bm; | |
1138 | GSList *ro_dirty_bitmaps = NULL; | |
f6333cbf VSO |
1139 | int ret = -EINVAL; |
1140 | bool need_header_update = false; | |
1b6b0562 VSO |
1141 | |
1142 | if (s->nb_bitmaps == 0) { | |
1143 | /* No bitmaps - nothing to do */ | |
1144 | return 0; | |
1145 | } | |
1146 | ||
1b6b0562 VSO |
1147 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, |
1148 | s->bitmap_directory_size, errp); | |
1149 | if (bm_list == NULL) { | |
1150 | return -EINVAL; | |
1151 | } | |
1152 | ||
1153 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
74da6b94 | 1154 | BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name); |
1b6b0562 | 1155 | |
f6333cbf VSO |
1156 | if (!bitmap) { |
1157 | error_setg(errp, "Unexpected bitmap '%s' in image '%s'", | |
1158 | bm->name, bs->filename); | |
74da6b94 | 1159 | goto out; |
1b6b0562 | 1160 | } |
74da6b94 | 1161 | |
f6333cbf VSO |
1162 | if (!(bm->flags & BME_FLAG_IN_USE)) { |
1163 | if (!bdrv_dirty_bitmap_readonly(bitmap)) { | |
1164 | error_setg(errp, "Corruption: bitmap '%s' is not marked IN_USE " | |
1165 | "in the image '%s' and not marked readonly in RAM", | |
1166 | bm->name, bs->filename); | |
1167 | goto out; | |
1168 | } | |
1169 | if (bdrv_dirty_bitmap_inconsistent(bitmap)) { | |
1170 | error_setg(errp, "Corruption: bitmap '%s' is inconsistent but " | |
1171 | "is not marked IN_USE in the image '%s'", bm->name, | |
1172 | bs->filename); | |
1173 | goto out; | |
1174 | } | |
1175 | ||
1176 | bm->flags |= BME_FLAG_IN_USE; | |
1177 | need_header_update = true; | |
1178 | } else { | |
1179 | /* | |
1180 | * What if flags already has BME_FLAG_IN_USE ? | |
1181 | * | |
1182 | * 1. if we are reopening RW -> RW it's OK, of course. | |
1183 | * 2. if we are reopening RO -> RW: | |
1184 | * 2.1 if @bitmap is inconsistent, it's OK. It means that it was | |
1185 | * inconsistent (IN_USE) when we loaded it | |
1186 | * 2.2 if @bitmap is not inconsistent. This seems to be impossible | |
1187 | * and implies third party interaction. Let's error-out for | |
1188 | * safety. | |
1189 | */ | |
1190 | if (bdrv_dirty_bitmap_readonly(bitmap) && | |
1191 | !bdrv_dirty_bitmap_inconsistent(bitmap)) | |
1192 | { | |
1193 | error_setg(errp, "Corruption: bitmap '%s' is marked IN_USE " | |
1194 | "in the image '%s' but it is readonly and " | |
1195 | "consistent in RAM", | |
1196 | bm->name, bs->filename); | |
1197 | goto out; | |
1198 | } | |
1199 | } | |
1200 | ||
1201 | if (bdrv_dirty_bitmap_readonly(bitmap)) { | |
1202 | ro_dirty_bitmaps = g_slist_append(ro_dirty_bitmaps, bitmap); | |
1203 | } | |
1b6b0562 VSO |
1204 | } |
1205 | ||
f6333cbf VSO |
1206 | if (need_header_update) { |
1207 | if (!can_write(bs->file->bs) || !(bs->file->perm & BLK_PERM_WRITE)) { | |
1208 | error_setg(errp, "Failed to reopen bitmaps rw: no write access " | |
1209 | "the protocol file"); | |
1210 | goto out; | |
1211 | } | |
1212 | ||
1b6b0562 VSO |
1213 | /* in_use flags must be updated */ |
1214 | ret = update_ext_header_and_dir_in_place(bs, bm_list); | |
1215 | if (ret < 0) { | |
f6333cbf | 1216 | error_setg_errno(errp, -ret, "Cannot update bitmap directory"); |
1b6b0562 VSO |
1217 | goto out; |
1218 | } | |
1b6b0562 VSO |
1219 | } |
1220 | ||
f6333cbf VSO |
1221 | g_slist_foreach(ro_dirty_bitmaps, set_readonly_helper, false); |
1222 | ret = 0; | |
1223 | ||
1b6b0562 VSO |
1224 | out: |
1225 | g_slist_free(ro_dirty_bitmaps); | |
1226 | bitmap_list_free(bm_list); | |
1227 | ||
1228 | return ret; | |
1229 | } | |
5f72826e | 1230 | |
d19c6b36 JS |
1231 | /* Checks to see if it's safe to resize bitmaps */ |
1232 | int qcow2_truncate_bitmaps_check(BlockDriverState *bs, Error **errp) | |
1233 | { | |
1234 | BDRVQcow2State *s = bs->opaque; | |
1235 | Qcow2BitmapList *bm_list; | |
1236 | Qcow2Bitmap *bm; | |
1237 | int ret = 0; | |
1238 | ||
1239 | if (s->nb_bitmaps == 0) { | |
1240 | return 0; | |
1241 | } | |
1242 | ||
1243 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1244 | s->bitmap_directory_size, errp); | |
1245 | if (bm_list == NULL) { | |
1246 | return -EINVAL; | |
1247 | } | |
1248 | ||
1249 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1250 | BdrvDirtyBitmap *bitmap = bdrv_find_dirty_bitmap(bs, bm->name); | |
1251 | if (bitmap == NULL) { | |
1252 | /* | |
1253 | * We rely on all bitmaps being in-memory to be able to resize them, | |
1254 | * Otherwise, we'd need to resize them on disk explicitly | |
1255 | */ | |
1256 | error_setg(errp, "Cannot resize qcow2 with persistent bitmaps that " | |
1257 | "were not loaded into memory"); | |
1258 | ret = -ENOTSUP; | |
1259 | goto out; | |
1260 | } | |
1261 | ||
1262 | /* | |
1263 | * The checks against readonly and busy are redundant, but certainly | |
1264 | * do no harm. checks against inconsistent are crucial: | |
1265 | */ | |
1266 | if (bdrv_dirty_bitmap_check(bitmap, BDRV_BITMAP_DEFAULT, errp)) { | |
1267 | ret = -ENOTSUP; | |
1268 | goto out; | |
1269 | } | |
1270 | } | |
1271 | ||
1272 | out: | |
1273 | bitmap_list_free(bm_list); | |
1274 | return ret; | |
1275 | } | |
1276 | ||
5f72826e VSO |
1277 | /* store_bitmap_data() |
1278 | * Store bitmap to image, filling bitmap table accordingly. | |
1279 | */ | |
1280 | static uint64_t *store_bitmap_data(BlockDriverState *bs, | |
1281 | BdrvDirtyBitmap *bitmap, | |
1282 | uint32_t *bitmap_table_size, Error **errp) | |
1283 | { | |
1284 | int ret; | |
1285 | BDRVQcow2State *s = bs->opaque; | |
49d741b5 EB |
1286 | int64_t offset; |
1287 | uint64_t limit; | |
5f72826e VSO |
1288 | uint64_t bm_size = bdrv_dirty_bitmap_size(bitmap); |
1289 | const char *bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1290 | uint8_t *buf = NULL; | |
5f72826e VSO |
1291 | uint64_t *tb; |
1292 | uint64_t tb_size = | |
1293 | size_to_clusters(s, | |
86f6ae67 | 1294 | bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size)); |
5f72826e VSO |
1295 | |
1296 | if (tb_size > BME_MAX_TABLE_SIZE || | |
1297 | tb_size * s->cluster_size > BME_MAX_PHYS_SIZE) | |
1298 | { | |
1299 | error_setg(errp, "Bitmap '%s' is too big", bm_name); | |
1300 | return NULL; | |
1301 | } | |
1302 | ||
1303 | tb = g_try_new0(uint64_t, tb_size); | |
1304 | if (tb == NULL) { | |
1305 | error_setg(errp, "No memory"); | |
1306 | return NULL; | |
1307 | } | |
1308 | ||
5f72826e | 1309 | buf = g_malloc(s->cluster_size); |
c7e7c87a | 1310 | limit = bytes_covered_by_bitmap_cluster(s, bitmap); |
c7e7c87a | 1311 | assert(DIV_ROUND_UP(bm_size, limit) == tb_size); |
5f72826e | 1312 | |
2d00cbd8 VSO |
1313 | offset = 0; |
1314 | while ((offset = bdrv_dirty_bitmap_next_dirty(bitmap, offset, INT64_MAX)) | |
1315 | >= 0) | |
1316 | { | |
49d741b5 | 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 | ||
2d00cbd8 | 1359 | offset = end; |
5f72826e VSO |
1360 | } |
1361 | ||
1362 | *bitmap_table_size = tb_size; | |
1363 | g_free(buf); | |
5f72826e VSO |
1364 | |
1365 | return tb; | |
1366 | ||
1367 | fail: | |
1368 | clear_bitmap_table(bs, tb, tb_size); | |
1369 | g_free(buf); | |
5f72826e VSO |
1370 | g_free(tb); |
1371 | ||
1372 | return NULL; | |
1373 | } | |
1374 | ||
1375 | /* store_bitmap() | |
1376 | * Store bm->dirty_bitmap to qcow2. | |
1377 | * Set bm->table_offset and bm->table_size accordingly. | |
1378 | */ | |
1379 | static int store_bitmap(BlockDriverState *bs, Qcow2Bitmap *bm, Error **errp) | |
1380 | { | |
1381 | int ret; | |
1382 | uint64_t *tb; | |
1383 | int64_t tb_offset; | |
1384 | uint32_t tb_size; | |
1385 | BdrvDirtyBitmap *bitmap = bm->dirty_bitmap; | |
1386 | const char *bm_name; | |
1387 | ||
1388 | assert(bitmap != NULL); | |
1389 | ||
1390 | bm_name = bdrv_dirty_bitmap_name(bitmap); | |
1391 | ||
1392 | tb = store_bitmap_data(bs, bitmap, &tb_size, errp); | |
1393 | if (tb == NULL) { | |
1394 | return -EINVAL; | |
1395 | } | |
1396 | ||
1397 | assert(tb_size <= BME_MAX_TABLE_SIZE); | |
1398 | tb_offset = qcow2_alloc_clusters(bs, tb_size * sizeof(tb[0])); | |
1399 | if (tb_offset < 0) { | |
1400 | error_setg_errno(errp, -tb_offset, | |
1401 | "Failed to allocate clusters for bitmap '%s'", | |
1402 | bm_name); | |
1403 | ret = tb_offset; | |
1404 | goto fail; | |
1405 | } | |
1406 | ||
1407 | ret = qcow2_pre_write_overlap_check(bs, 0, tb_offset, | |
966b000f | 1408 | tb_size * sizeof(tb[0]), false); |
5f72826e VSO |
1409 | if (ret < 0) { |
1410 | error_setg_errno(errp, -ret, "Qcow2 overlap check failed"); | |
1411 | goto fail; | |
1412 | } | |
1413 | ||
1414 | bitmap_table_to_be(tb, tb_size); | |
1415 | ret = bdrv_pwrite(bs->file, tb_offset, tb, tb_size * sizeof(tb[0])); | |
1416 | if (ret < 0) { | |
1417 | error_setg_errno(errp, -ret, "Failed to write bitmap '%s' to file", | |
1418 | bm_name); | |
1419 | goto fail; | |
1420 | } | |
1421 | ||
1422 | g_free(tb); | |
1423 | ||
1424 | bm->table.offset = tb_offset; | |
1425 | bm->table.size = tb_size; | |
1426 | ||
1427 | return 0; | |
1428 | ||
1429 | fail: | |
1430 | clear_bitmap_table(bs, tb, tb_size); | |
1431 | ||
1432 | if (tb_offset > 0) { | |
1433 | qcow2_free_clusters(bs, tb_offset, tb_size * sizeof(tb[0]), | |
1434 | QCOW2_DISCARD_OTHER); | |
1435 | } | |
1436 | ||
1437 | g_free(tb); | |
1438 | ||
1439 | return ret; | |
1440 | } | |
1441 | ||
1442 | static Qcow2Bitmap *find_bitmap_by_name(Qcow2BitmapList *bm_list, | |
1443 | const char *name) | |
1444 | { | |
1445 | Qcow2Bitmap *bm; | |
1446 | ||
1447 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1448 | if (strcmp(name, bm->name) == 0) { | |
1449 | return bm; | |
1450 | } | |
1451 | } | |
1452 | ||
1453 | return NULL; | |
1454 | } | |
1455 | ||
d2c3080e VSO |
1456 | int coroutine_fn qcow2_co_remove_persistent_dirty_bitmap(BlockDriverState *bs, |
1457 | const char *name, | |
1458 | Error **errp) | |
469c71ed VSO |
1459 | { |
1460 | int ret; | |
1461 | BDRVQcow2State *s = bs->opaque; | |
d2c3080e | 1462 | Qcow2Bitmap *bm = NULL; |
469c71ed VSO |
1463 | Qcow2BitmapList *bm_list; |
1464 | ||
1465 | if (s->nb_bitmaps == 0) { | |
f56281ab VSO |
1466 | /* |
1467 | * Absence of the bitmap is not an error: see explanation above | |
1468 | * bdrv_co_remove_persistent_dirty_bitmap() definition. | |
1469 | */ | |
b56a1e31 | 1470 | return 0; |
469c71ed VSO |
1471 | } |
1472 | ||
d2c3080e VSO |
1473 | qemu_co_mutex_lock(&s->lock); |
1474 | ||
469c71ed VSO |
1475 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, |
1476 | s->bitmap_directory_size, errp); | |
1477 | if (bm_list == NULL) { | |
d2c3080e VSO |
1478 | ret = -EIO; |
1479 | goto out; | |
469c71ed VSO |
1480 | } |
1481 | ||
1482 | bm = find_bitmap_by_name(bm_list, name); | |
1483 | if (bm == NULL) { | |
f56281ab VSO |
1484 | /* Absence of the bitmap is not an error, see above. */ |
1485 | ret = 0; | |
b56a1e31 | 1486 | goto out; |
469c71ed VSO |
1487 | } |
1488 | ||
1489 | QSIMPLEQ_REMOVE(bm_list, bm, Qcow2Bitmap, entry); | |
1490 | ||
1491 | ret = update_ext_header_and_dir(bs, bm_list); | |
1492 | if (ret < 0) { | |
1493 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
b56a1e31 | 1494 | goto out; |
469c71ed VSO |
1495 | } |
1496 | ||
1497 | free_bitmap_clusters(bs, &bm->table); | |
1498 | ||
b56a1e31 | 1499 | out: |
d2c3080e VSO |
1500 | qemu_co_mutex_unlock(&s->lock); |
1501 | ||
469c71ed VSO |
1502 | bitmap_free(bm); |
1503 | bitmap_list_free(bm_list); | |
b56a1e31 VSO |
1504 | |
1505 | return ret; | |
469c71ed VSO |
1506 | } |
1507 | ||
644ddbb7 VSO |
1508 | /* |
1509 | * qcow2_store_persistent_dirty_bitmaps | |
1510 | * | |
1511 | * Stores persistent BdrvDirtyBitmap objects. | |
1512 | * | |
1513 | * @release_stored: if true, release BdrvDirtyBitmap's after storing to the | |
1514 | * image. This is used in two cases, both via qcow2_inactivate: | |
1515 | * 1. bdrv_close: It's correct to remove bitmaps on close. | |
1516 | * 2. migration: If bitmaps are migrated through migration channel via | |
1517 | * 'dirty-bitmaps' migration capability they are not handled by this code. | |
1518 | * Otherwise, it's OK to drop BdrvDirtyBitmap's and reload them on | |
1519 | * invalidation. | |
1520 | * | |
1521 | * Anyway, it's correct to remove BdrvDirtyBitmap's on inactivation, as | |
1522 | * inactivation means that we lose control on disk, and therefore on bitmaps, | |
1523 | * we should sync them and do not touch more. | |
1524 | * | |
1525 | * Contrariwise, we don't want to release any bitmaps on just reopen-to-ro, | |
1526 | * when we need to store them, as image is still under our control, and it's | |
1527 | * good to keep all the bitmaps in read-only mode. Moreover, keeping them | |
1528 | * read-only is correct because this is what would happen if we opened the node | |
1529 | * readonly to begin with, and whether we opened directly or reopened to that | |
1530 | * state shouldn't matter for the state we get afterward. | |
1531 | */ | |
1532 | void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, | |
1533 | bool release_stored, Error **errp) | |
5f72826e VSO |
1534 | { |
1535 | BdrvDirtyBitmap *bitmap; | |
1536 | BDRVQcow2State *s = bs->opaque; | |
1537 | uint32_t new_nb_bitmaps = s->nb_bitmaps; | |
1538 | uint64_t new_dir_size = s->bitmap_directory_size; | |
1539 | int ret; | |
1540 | Qcow2BitmapList *bm_list; | |
1541 | Qcow2Bitmap *bm; | |
b58deb34 | 1542 | QSIMPLEQ_HEAD(, Qcow2BitmapTable) drop_tables; |
5f72826e | 1543 | Qcow2BitmapTable *tb, *tb_next; |
f88676c1 | 1544 | bool need_write = false; |
5f72826e VSO |
1545 | |
1546 | QSIMPLEQ_INIT(&drop_tables); | |
1547 | ||
1548 | if (s->nb_bitmaps == 0) { | |
1549 | bm_list = bitmap_list_new(); | |
1550 | } else { | |
1551 | bm_list = bitmap_list_load(bs, s->bitmap_directory_offset, | |
1552 | s->bitmap_directory_size, errp); | |
1553 | if (bm_list == NULL) { | |
1554 | return; | |
1555 | } | |
1556 | } | |
1557 | ||
1558 | /* check constraints and names */ | |
ef9041a7 | 1559 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
5f72826e VSO |
1560 | const char *name = bdrv_dirty_bitmap_name(bitmap); |
1561 | uint32_t granularity = bdrv_dirty_bitmap_granularity(bitmap); | |
1562 | Qcow2Bitmap *bm; | |
1563 | ||
796a3798 | 1564 | if (!bdrv_dirty_bitmap_get_persistence(bitmap) || |
74da6b94 JS |
1565 | bdrv_dirty_bitmap_readonly(bitmap) || |
1566 | bdrv_dirty_bitmap_inconsistent(bitmap)) { | |
5f72826e VSO |
1567 | continue; |
1568 | } | |
1569 | ||
f88676c1 VSO |
1570 | need_write = true; |
1571 | ||
5f72826e VSO |
1572 | if (check_constraints_on_bitmap(bs, name, granularity, errp) < 0) { |
1573 | error_prepend(errp, "Bitmap '%s' doesn't satisfy the constraints: ", | |
1574 | name); | |
1575 | goto fail; | |
1576 | } | |
1577 | ||
1578 | bm = find_bitmap_by_name(bm_list, name); | |
1579 | if (bm == NULL) { | |
1580 | if (++new_nb_bitmaps > QCOW2_MAX_BITMAPS) { | |
1581 | error_setg(errp, "Too many persistent bitmaps"); | |
1582 | goto fail; | |
1583 | } | |
1584 | ||
1585 | new_dir_size += calc_dir_entry_size(strlen(name), 0); | |
1586 | if (new_dir_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { | |
1587 | error_setg(errp, "Bitmap directory is too large"); | |
1588 | goto fail; | |
1589 | } | |
1590 | ||
1591 | bm = g_new0(Qcow2Bitmap, 1); | |
1592 | bm->name = g_strdup(name); | |
1593 | QSIMPLEQ_INSERT_TAIL(bm_list, bm, entry); | |
1594 | } else { | |
1595 | if (!(bm->flags & BME_FLAG_IN_USE)) { | |
1596 | error_setg(errp, "Bitmap '%s' already exists in the image", | |
1597 | name); | |
1598 | goto fail; | |
1599 | } | |
1600 | tb = g_memdup(&bm->table, sizeof(bm->table)); | |
1601 | bm->table.offset = 0; | |
1602 | bm->table.size = 0; | |
1603 | QSIMPLEQ_INSERT_TAIL(&drop_tables, tb, entry); | |
1604 | } | |
3e99da5e | 1605 | bm->flags = bdrv_dirty_bitmap_enabled(bitmap) ? BME_FLAG_AUTO : 0; |
5f72826e VSO |
1606 | bm->granularity_bits = ctz32(bdrv_dirty_bitmap_granularity(bitmap)); |
1607 | bm->dirty_bitmap = bitmap; | |
1608 | } | |
1609 | ||
f88676c1 VSO |
1610 | if (!need_write) { |
1611 | goto success; | |
1612 | } | |
1613 | ||
1614 | if (!can_write(bs)) { | |
1615 | error_setg(errp, "No write access"); | |
1616 | goto fail; | |
1617 | } | |
1618 | ||
5f72826e VSO |
1619 | /* allocate clusters and store bitmaps */ |
1620 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1621 | if (bm->dirty_bitmap == NULL) { | |
1622 | continue; | |
1623 | } | |
1624 | ||
1625 | ret = store_bitmap(bs, bm, errp); | |
1626 | if (ret < 0) { | |
1627 | goto fail; | |
1628 | } | |
1629 | } | |
1630 | ||
1631 | ret = update_ext_header_and_dir(bs, bm_list); | |
1632 | if (ret < 0) { | |
1633 | error_setg_errno(errp, -ret, "Failed to update bitmap extension"); | |
1634 | goto fail; | |
1635 | } | |
1636 | ||
1637 | /* Bitmap directory was successfully updated, so, old data can be dropped. | |
1638 | * TODO it is better to reuse these clusters */ | |
1639 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1640 | free_bitmap_clusters(bs, tb); | |
1641 | g_free(tb); | |
1642 | } | |
1643 | ||
644ddbb7 VSO |
1644 | if (release_stored) { |
1645 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1646 | if (bm->dirty_bitmap == NULL) { | |
1647 | continue; | |
1648 | } | |
9c98f145 | 1649 | |
644ddbb7 VSO |
1650 | bdrv_release_dirty_bitmap(bm->dirty_bitmap); |
1651 | } | |
9c98f145 VSO |
1652 | } |
1653 | ||
f88676c1 | 1654 | success: |
5f72826e VSO |
1655 | bitmap_list_free(bm_list); |
1656 | return; | |
1657 | ||
1658 | fail: | |
1659 | QSIMPLEQ_FOREACH(bm, bm_list, entry) { | |
1660 | if (bm->dirty_bitmap == NULL || bm->table.offset == 0) { | |
1661 | continue; | |
1662 | } | |
1663 | ||
1664 | free_bitmap_clusters(bs, &bm->table); | |
1665 | } | |
1666 | ||
1667 | QSIMPLEQ_FOREACH_SAFE(tb, &drop_tables, entry, tb_next) { | |
1668 | g_free(tb); | |
1669 | } | |
1670 | ||
1671 | bitmap_list_free(bm_list); | |
1672 | } | |
169b8793 VSO |
1673 | |
1674 | int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp) | |
1675 | { | |
1676 | BdrvDirtyBitmap *bitmap; | |
1677 | Error *local_err = NULL; | |
1678 | ||
644ddbb7 | 1679 | qcow2_store_persistent_dirty_bitmaps(bs, false, &local_err); |
169b8793 VSO |
1680 | if (local_err != NULL) { |
1681 | error_propagate(errp, local_err); | |
1682 | return -EINVAL; | |
1683 | } | |
1684 | ||
ef9041a7 | 1685 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
796a3798 | 1686 | if (bdrv_dirty_bitmap_get_persistence(bitmap)) { |
169b8793 VSO |
1687 | bdrv_dirty_bitmap_set_readonly(bitmap, true); |
1688 | } | |
1689 | } | |
1690 | ||
1691 | return 0; | |
1692 | } | |
da0eb242 | 1693 | |
d2c3080e VSO |
1694 | bool coroutine_fn qcow2_co_can_store_new_dirty_bitmap(BlockDriverState *bs, |
1695 | const char *name, | |
1696 | uint32_t granularity, | |
1697 | Error **errp) | |
da0eb242 VSO |
1698 | { |
1699 | BDRVQcow2State *s = bs->opaque; | |
a1db8733 VSO |
1700 | BdrvDirtyBitmap *bitmap; |
1701 | uint64_t bitmap_directory_size = 0; | |
1702 | uint32_t nb_bitmaps = 0; | |
1703 | ||
1704 | if (bdrv_find_dirty_bitmap(bs, name)) { | |
1705 | error_setg(errp, "Bitmap already exists: %s", name); | |
1706 | return false; | |
1707 | } | |
da0eb242 | 1708 | |
c9ceb3ec HR |
1709 | if (s->qcow_version < 3) { |
1710 | /* Without autoclear_features, we would always have to assume | |
1711 | * that a program without persistent dirty bitmap support has | |
1712 | * accessed this qcow2 file when opening it, and would thus | |
1713 | * have to drop all dirty bitmaps (defeating their purpose). | |
1714 | */ | |
1715 | error_setg(errp, "Cannot store dirty bitmaps in qcow2 v2 files"); | |
1716 | goto fail; | |
1717 | } | |
1718 | ||
da0eb242 VSO |
1719 | if (check_constraints_on_bitmap(bs, name, granularity, errp) != 0) { |
1720 | goto fail; | |
1721 | } | |
1722 | ||
a1db8733 VSO |
1723 | FOR_EACH_DIRTY_BITMAP(bs, bitmap) { |
1724 | if (bdrv_dirty_bitmap_get_persistence(bitmap)) { | |
1725 | nb_bitmaps++; | |
1726 | bitmap_directory_size += | |
1727 | calc_dir_entry_size(strlen(bdrv_dirty_bitmap_name(bitmap)), 0); | |
1728 | } | |
da0eb242 | 1729 | } |
a1db8733 VSO |
1730 | nb_bitmaps++; |
1731 | bitmap_directory_size += calc_dir_entry_size(strlen(name), 0); | |
da0eb242 | 1732 | |
a1db8733 | 1733 | if (nb_bitmaps > QCOW2_MAX_BITMAPS) { |
da0eb242 VSO |
1734 | error_setg(errp, |
1735 | "Maximum number of persistent bitmaps is already reached"); | |
1736 | goto fail; | |
1737 | } | |
1738 | ||
a1db8733 | 1739 | if (bitmap_directory_size > QCOW2_MAX_BITMAP_DIRECTORY_SIZE) { |
da0eb242 VSO |
1740 | error_setg(errp, "Not enough space in the bitmap directory"); |
1741 | goto fail; | |
1742 | } | |
1743 | ||
da0eb242 VSO |
1744 | return true; |
1745 | ||
1746 | fail: | |
1747 | error_prepend(errp, "Can't make bitmap '%s' persistent in '%s': ", | |
1748 | name, bdrv_get_device_or_node_name(bs)); | |
1749 | return false; | |
1750 | } | |
ef893b5c EB |
1751 | |
1752 | bool qcow2_supports_persistent_dirty_bitmap(BlockDriverState *bs) | |
1753 | { | |
1754 | BDRVQcow2State *s = bs->opaque; | |
1755 | ||
1756 | return s->qcow_version >= 3; | |
1757 | } | |
5d72c68b EB |
1758 | |
1759 | /* | |
1760 | * Compute the space required for bitmaps in @bs. | |
1761 | * | |
1762 | * The computation is based as if copying to a new image with the | |
1763 | * given @cluster_size, which may differ from the cluster size in @bs. | |
1764 | */ | |
1765 | uint64_t qcow2_get_persistent_dirty_bitmap_size(BlockDriverState *bs, | |
1766 | uint32_t cluster_size) | |
1767 | { | |
1768 | uint64_t bitmaps_size = 0; | |
1769 | BdrvDirtyBitmap *bm; | |
1770 | size_t bitmap_dir_size = 0; | |
1771 | ||
1772 | FOR_EACH_DIRTY_BITMAP(bs, bm) { | |
1773 | if (bdrv_dirty_bitmap_get_persistence(bm)) { | |
1774 | const char *name = bdrv_dirty_bitmap_name(bm); | |
1775 | uint32_t granularity = bdrv_dirty_bitmap_granularity(bm); | |
1776 | uint64_t bmbytes = | |
1777 | get_bitmap_bytes_needed(bdrv_dirty_bitmap_size(bm), | |
1778 | granularity); | |
1779 | uint64_t bmclusters = DIV_ROUND_UP(bmbytes, cluster_size); | |
1780 | ||
1781 | /* Assume the entire bitmap is allocated */ | |
1782 | bitmaps_size += bmclusters * cluster_size; | |
1783 | /* Also reserve space for the bitmap table entries */ | |
1784 | bitmaps_size += ROUND_UP(bmclusters * sizeof(uint64_t), | |
1785 | cluster_size); | |
1786 | /* And space for contribution to bitmap directory size */ | |
1787 | bitmap_dir_size += calc_dir_entry_size(strlen(name), 0); | |
1788 | } | |
1789 | } | |
1790 | bitmaps_size += ROUND_UP(bitmap_dir_size, cluster_size); | |
1791 | ||
1792 | return bitmaps_size; | |
1793 | } |