1 /* 2 * Block driver for the QCOW version 2 format 3 * 4 * Copyright (c) 2004-2006 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 25 #ifndef BLOCK_QCOW2_H 26 #define BLOCK_QCOW2_H 27 28 #include "crypto/cipher.h" 29 #include "block/coroutine.h" 30 31 //#define DEBUG_ALLOC 32 //#define DEBUG_ALLOC2 33 //#define DEBUG_EXT 34 35 #define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) 36 37 #define QCOW_CRYPT_NONE 0 38 #define QCOW_CRYPT_AES 1 39 40 #define QCOW_MAX_CRYPT_CLUSTERS 32 41 #define QCOW_MAX_SNAPSHOTS 65536 42 43 /* 8 MB refcount table is enough for 2 PB images at 64k cluster size 44 * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */ 45 #define QCOW_MAX_REFTABLE_SIZE 0x800000 46 47 /* 32 MB L1 table is enough for 2 PB images at 64k cluster size 48 * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */ 49 #define QCOW_MAX_L1_SIZE 0x2000000 50 51 /* Allow for an average of 1k per snapshot table entry, should be plenty of 52 * space for snapshot names and IDs */ 53 #define QCOW_MAX_SNAPSHOTS_SIZE (1024 * QCOW_MAX_SNAPSHOTS) 54 55 /* indicate that the refcount of the referenced cluster is exactly one. */ 56 #define QCOW_OFLAG_COPIED (1ULL << 63) 57 /* indicate that the cluster is compressed (they never have the copied flag) */ 58 #define QCOW_OFLAG_COMPRESSED (1ULL << 62) 59 /* The cluster reads as all zeros */ 60 #define QCOW_OFLAG_ZERO (1ULL << 0) 61 62 #define MIN_CLUSTER_BITS 9 63 #define MAX_CLUSTER_BITS 21 64 65 /* Must be at least 2 to cover COW */ 66 #define MIN_L2_CACHE_SIZE 2 /* clusters */ 67 68 /* Must be at least 4 to cover all cases of refcount table growth */ 69 #define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */ 70 71 /* Whichever is more */ 72 #define DEFAULT_L2_CACHE_CLUSTERS 8 /* clusters */ 73 #define DEFAULT_L2_CACHE_BYTE_SIZE 1048576 /* bytes */ 74 75 /* The refblock cache needs only a fourth of the L2 cache size to cover as many 76 * clusters */ 77 #define DEFAULT_L2_REFCOUNT_SIZE_RATIO 4 78 79 #define DEFAULT_CLUSTER_SIZE 65536 80 81 82 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts" 83 #define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request" 84 #define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot" 85 #define QCOW2_OPT_DISCARD_OTHER "pass-discard-other" 86 #define QCOW2_OPT_OVERLAP "overlap-check" 87 #define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template" 88 #define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header" 89 #define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1" 90 #define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2" 91 #define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table" 92 #define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block" 93 #define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table" 94 #define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1" 95 #define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2" 96 #define QCOW2_OPT_CACHE_SIZE "cache-size" 97 #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size" 98 #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size" 99 #define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval" 100 101 typedef struct QCowHeader { 102 uint32_t magic; 103 uint32_t version; 104 uint64_t backing_file_offset; 105 uint32_t backing_file_size; 106 uint32_t cluster_bits; 107 uint64_t size; /* in bytes */ 108 uint32_t crypt_method; 109 uint32_t l1_size; /* XXX: save number of clusters instead ? */ 110 uint64_t l1_table_offset; 111 uint64_t refcount_table_offset; 112 uint32_t refcount_table_clusters; 113 uint32_t nb_snapshots; 114 uint64_t snapshots_offset; 115 116 /* The following fields are only valid for version >= 3 */ 117 uint64_t incompatible_features; 118 uint64_t compatible_features; 119 uint64_t autoclear_features; 120 121 uint32_t refcount_order; 122 uint32_t header_length; 123 } QEMU_PACKED QCowHeader; 124 125 typedef struct QEMU_PACKED QCowSnapshotHeader { 126 /* header is 8 byte aligned */ 127 uint64_t l1_table_offset; 128 129 uint32_t l1_size; 130 uint16_t id_str_size; 131 uint16_t name_size; 132 133 uint32_t date_sec; 134 uint32_t date_nsec; 135 136 uint64_t vm_clock_nsec; 137 138 uint32_t vm_state_size; 139 uint32_t extra_data_size; /* for extension */ 140 /* extra data follows */ 141 /* id_str follows */ 142 /* name follows */ 143 } QCowSnapshotHeader; 144 145 typedef struct QEMU_PACKED QCowSnapshotExtraData { 146 uint64_t vm_state_size_large; 147 uint64_t disk_size; 148 } QCowSnapshotExtraData; 149 150 151 typedef struct QCowSnapshot { 152 uint64_t l1_table_offset; 153 uint32_t l1_size; 154 char *id_str; 155 char *name; 156 uint64_t disk_size; 157 uint64_t vm_state_size; 158 uint32_t date_sec; 159 uint32_t date_nsec; 160 uint64_t vm_clock_nsec; 161 } QCowSnapshot; 162 163 struct Qcow2Cache; 164 typedef struct Qcow2Cache Qcow2Cache; 165 166 typedef struct Qcow2UnknownHeaderExtension { 167 uint32_t magic; 168 uint32_t len; 169 QLIST_ENTRY(Qcow2UnknownHeaderExtension) next; 170 uint8_t data[]; 171 } Qcow2UnknownHeaderExtension; 172 173 enum { 174 QCOW2_FEAT_TYPE_INCOMPATIBLE = 0, 175 QCOW2_FEAT_TYPE_COMPATIBLE = 1, 176 QCOW2_FEAT_TYPE_AUTOCLEAR = 2, 177 }; 178 179 /* Incompatible feature bits */ 180 enum { 181 QCOW2_INCOMPAT_DIRTY_BITNR = 0, 182 QCOW2_INCOMPAT_CORRUPT_BITNR = 1, 183 QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR, 184 QCOW2_INCOMPAT_CORRUPT = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR, 185 186 QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY 187 | QCOW2_INCOMPAT_CORRUPT, 188 }; 189 190 /* Compatible feature bits */ 191 enum { 192 QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0, 193 QCOW2_COMPAT_LAZY_REFCOUNTS = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR, 194 195 QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS, 196 }; 197 198 enum qcow2_discard_type { 199 QCOW2_DISCARD_NEVER = 0, 200 QCOW2_DISCARD_ALWAYS, 201 QCOW2_DISCARD_REQUEST, 202 QCOW2_DISCARD_SNAPSHOT, 203 QCOW2_DISCARD_OTHER, 204 QCOW2_DISCARD_MAX 205 }; 206 207 typedef struct Qcow2Feature { 208 uint8_t type; 209 uint8_t bit; 210 char name[46]; 211 } QEMU_PACKED Qcow2Feature; 212 213 typedef struct Qcow2DiscardRegion { 214 BlockDriverState *bs; 215 uint64_t offset; 216 uint64_t bytes; 217 QTAILQ_ENTRY(Qcow2DiscardRegion) next; 218 } Qcow2DiscardRegion; 219 220 typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array, 221 uint64_t index); 222 typedef void Qcow2SetRefcountFunc(void *refcount_array, 223 uint64_t index, uint64_t value); 224 225 typedef struct BDRVQcowState { 226 int cluster_bits; 227 int cluster_size; 228 int cluster_sectors; 229 int l2_bits; 230 int l2_size; 231 int l1_size; 232 int l1_vm_state_index; 233 int refcount_block_bits; 234 int refcount_block_size; 235 int csize_shift; 236 int csize_mask; 237 uint64_t cluster_offset_mask; 238 uint64_t l1_table_offset; 239 uint64_t *l1_table; 240 241 Qcow2Cache* l2_table_cache; 242 Qcow2Cache* refcount_block_cache; 243 QEMUTimer *cache_clean_timer; 244 unsigned cache_clean_interval; 245 246 uint8_t *cluster_cache; 247 uint8_t *cluster_data; 248 uint64_t cluster_cache_offset; 249 QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs; 250 251 uint64_t *refcount_table; 252 uint64_t refcount_table_offset; 253 uint32_t refcount_table_size; 254 uint64_t free_cluster_index; 255 uint64_t free_byte_offset; 256 257 CoMutex lock; 258 259 QCryptoCipher *cipher; /* current cipher, NULL if no key yet */ 260 uint32_t crypt_method_header; 261 uint64_t snapshots_offset; 262 int snapshots_size; 263 unsigned int nb_snapshots; 264 QCowSnapshot *snapshots; 265 266 int flags; 267 int qcow_version; 268 bool use_lazy_refcounts; 269 int refcount_order; 270 int refcount_bits; 271 uint64_t refcount_max; 272 273 Qcow2GetRefcountFunc *get_refcount; 274 Qcow2SetRefcountFunc *set_refcount; 275 276 bool discard_passthrough[QCOW2_DISCARD_MAX]; 277 278 int overlap_check; /* bitmask of Qcow2MetadataOverlap values */ 279 bool signaled_corruption; 280 281 uint64_t incompatible_features; 282 uint64_t compatible_features; 283 uint64_t autoclear_features; 284 285 size_t unknown_header_fields_size; 286 void* unknown_header_fields; 287 QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext; 288 QTAILQ_HEAD (, Qcow2DiscardRegion) discards; 289 bool cache_discards; 290 291 /* Backing file path and format as stored in the image (this is not the 292 * effective path/format, which may be the result of a runtime option 293 * override) */ 294 char *image_backing_file; 295 char *image_backing_format; 296 } BDRVQcowState; 297 298 struct QCowAIOCB; 299 300 typedef struct Qcow2COWRegion { 301 /** 302 * Offset of the COW region in bytes from the start of the first cluster 303 * touched by the request. 304 */ 305 uint64_t offset; 306 307 /** Number of sectors to copy */ 308 int nb_sectors; 309 } Qcow2COWRegion; 310 311 /** 312 * Describes an in-flight (part of a) write request that writes to clusters 313 * that are not referenced in their L2 table yet. 314 */ 315 typedef struct QCowL2Meta 316 { 317 /** Guest offset of the first newly allocated cluster */ 318 uint64_t offset; 319 320 /** Host offset of the first newly allocated cluster */ 321 uint64_t alloc_offset; 322 323 /** 324 * Number of sectors from the start of the first allocated cluster to 325 * the end of the (possibly shortened) request 326 */ 327 int nb_available; 328 329 /** Number of newly allocated clusters */ 330 int nb_clusters; 331 332 /** 333 * Requests that overlap with this allocation and wait to be restarted 334 * when the allocating request has completed. 335 */ 336 CoQueue dependent_requests; 337 338 /** 339 * The COW Region between the start of the first allocated cluster and the 340 * area the guest actually writes to. 341 */ 342 Qcow2COWRegion cow_start; 343 344 /** 345 * The COW Region between the area the guest actually writes to and the 346 * end of the last allocated cluster. 347 */ 348 Qcow2COWRegion cow_end; 349 350 /** Pointer to next L2Meta of the same write request */ 351 struct QCowL2Meta *next; 352 353 QLIST_ENTRY(QCowL2Meta) next_in_flight; 354 } QCowL2Meta; 355 356 enum { 357 QCOW2_CLUSTER_UNALLOCATED, 358 QCOW2_CLUSTER_NORMAL, 359 QCOW2_CLUSTER_COMPRESSED, 360 QCOW2_CLUSTER_ZERO 361 }; 362 363 typedef enum QCow2MetadataOverlap { 364 QCOW2_OL_MAIN_HEADER_BITNR = 0, 365 QCOW2_OL_ACTIVE_L1_BITNR = 1, 366 QCOW2_OL_ACTIVE_L2_BITNR = 2, 367 QCOW2_OL_REFCOUNT_TABLE_BITNR = 3, 368 QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4, 369 QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5, 370 QCOW2_OL_INACTIVE_L1_BITNR = 6, 371 QCOW2_OL_INACTIVE_L2_BITNR = 7, 372 373 QCOW2_OL_MAX_BITNR = 8, 374 375 QCOW2_OL_NONE = 0, 376 QCOW2_OL_MAIN_HEADER = (1 << QCOW2_OL_MAIN_HEADER_BITNR), 377 QCOW2_OL_ACTIVE_L1 = (1 << QCOW2_OL_ACTIVE_L1_BITNR), 378 QCOW2_OL_ACTIVE_L2 = (1 << QCOW2_OL_ACTIVE_L2_BITNR), 379 QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR), 380 QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR), 381 QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR), 382 QCOW2_OL_INACTIVE_L1 = (1 << QCOW2_OL_INACTIVE_L1_BITNR), 383 /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv 384 * reads. */ 385 QCOW2_OL_INACTIVE_L2 = (1 << QCOW2_OL_INACTIVE_L2_BITNR), 386 } QCow2MetadataOverlap; 387 388 /* Perform all overlap checks which can be done in constant time */ 389 #define QCOW2_OL_CONSTANT \ 390 (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \ 391 QCOW2_OL_SNAPSHOT_TABLE) 392 393 /* Perform all overlap checks which don't require disk access */ 394 #define QCOW2_OL_CACHED \ 395 (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \ 396 QCOW2_OL_INACTIVE_L1) 397 398 /* Perform all overlap checks */ 399 #define QCOW2_OL_ALL \ 400 (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2) 401 402 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL 403 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL 404 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL 405 406 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL 407 408 static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset) 409 { 410 return offset & ~(s->cluster_size - 1); 411 } 412 413 static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset) 414 { 415 return offset & (s->cluster_size - 1); 416 } 417 418 static inline int size_to_clusters(BDRVQcowState *s, int64_t size) 419 { 420 return (size + (s->cluster_size - 1)) >> s->cluster_bits; 421 } 422 423 static inline int64_t size_to_l1(BDRVQcowState *s, int64_t size) 424 { 425 int shift = s->cluster_bits + s->l2_bits; 426 return (size + (1ULL << shift) - 1) >> shift; 427 } 428 429 static inline int offset_to_l2_index(BDRVQcowState *s, int64_t offset) 430 { 431 return (offset >> s->cluster_bits) & (s->l2_size - 1); 432 } 433 434 static inline int64_t align_offset(int64_t offset, int n) 435 { 436 offset = (offset + n - 1) & ~(n - 1); 437 return offset; 438 } 439 440 static inline int64_t qcow2_vm_state_offset(BDRVQcowState *s) 441 { 442 return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits); 443 } 444 445 static inline uint64_t qcow2_max_refcount_clusters(BDRVQcowState *s) 446 { 447 return QCOW_MAX_REFTABLE_SIZE >> s->cluster_bits; 448 } 449 450 static inline int qcow2_get_cluster_type(uint64_t l2_entry) 451 { 452 if (l2_entry & QCOW_OFLAG_COMPRESSED) { 453 return QCOW2_CLUSTER_COMPRESSED; 454 } else if (l2_entry & QCOW_OFLAG_ZERO) { 455 return QCOW2_CLUSTER_ZERO; 456 } else if (!(l2_entry & L2E_OFFSET_MASK)) { 457 return QCOW2_CLUSTER_UNALLOCATED; 458 } else { 459 return QCOW2_CLUSTER_NORMAL; 460 } 461 } 462 463 /* Check whether refcounts are eager or lazy */ 464 static inline bool qcow2_need_accurate_refcounts(BDRVQcowState *s) 465 { 466 return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY); 467 } 468 469 static inline uint64_t l2meta_cow_start(QCowL2Meta *m) 470 { 471 return m->offset + m->cow_start.offset; 472 } 473 474 static inline uint64_t l2meta_cow_end(QCowL2Meta *m) 475 { 476 return m->offset + m->cow_end.offset 477 + (m->cow_end.nb_sectors << BDRV_SECTOR_BITS); 478 } 479 480 static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2) 481 { 482 return r1 > r2 ? r1 - r2 : r2 - r1; 483 } 484 485 // FIXME Need qcow2_ prefix to global functions 486 487 /* qcow2.c functions */ 488 int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov, 489 int64_t sector_num, int nb_sectors); 490 491 int qcow2_mark_dirty(BlockDriverState *bs); 492 int qcow2_mark_corrupt(BlockDriverState *bs); 493 int qcow2_mark_consistent(BlockDriverState *bs); 494 int qcow2_update_header(BlockDriverState *bs); 495 496 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset, 497 int64_t size, const char *message_format, ...) 498 GCC_FMT_ATTR(5, 6); 499 500 /* qcow2-refcount.c functions */ 501 int qcow2_refcount_init(BlockDriverState *bs); 502 void qcow2_refcount_close(BlockDriverState *bs); 503 504 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index, 505 uint64_t *refcount); 506 507 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index, 508 uint64_t addend, bool decrease, 509 enum qcow2_discard_type type); 510 511 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size); 512 int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, 513 int nb_clusters); 514 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size); 515 void qcow2_free_clusters(BlockDriverState *bs, 516 int64_t offset, int64_t size, 517 enum qcow2_discard_type type); 518 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry, 519 int nb_clusters, enum qcow2_discard_type type); 520 521 int qcow2_update_snapshot_refcount(BlockDriverState *bs, 522 int64_t l1_table_offset, int l1_size, int addend); 523 524 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 525 BdrvCheckMode fix); 526 527 void qcow2_process_discards(BlockDriverState *bs, int ret); 528 529 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset, 530 int64_t size); 531 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset, 532 int64_t size); 533 534 /* qcow2-cluster.c functions */ 535 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size, 536 bool exact_size); 537 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index); 538 void qcow2_l2_cache_reset(BlockDriverState *bs); 539 int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset); 540 int qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num, 541 uint8_t *out_buf, const uint8_t *in_buf, 542 int nb_sectors, bool enc, Error **errp); 543 544 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, 545 int *num, uint64_t *cluster_offset); 546 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, 547 int *num, uint64_t *host_offset, QCowL2Meta **m); 548 uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, 549 uint64_t offset, 550 int compressed_size); 551 552 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m); 553 int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset, 554 int nb_sectors, enum qcow2_discard_type type, bool full_discard); 555 int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors); 556 557 int qcow2_expand_zero_clusters(BlockDriverState *bs, 558 BlockDriverAmendStatusCB *status_cb); 559 560 /* qcow2-snapshot.c functions */ 561 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info); 562 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id); 563 int qcow2_snapshot_delete(BlockDriverState *bs, 564 const char *snapshot_id, 565 const char *name, 566 Error **errp); 567 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab); 568 int qcow2_snapshot_load_tmp(BlockDriverState *bs, 569 const char *snapshot_id, 570 const char *name, 571 Error **errp); 572 573 void qcow2_free_snapshots(BlockDriverState *bs); 574 int qcow2_read_snapshots(BlockDriverState *bs); 575 576 /* qcow2-cache.c functions */ 577 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables); 578 int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c); 579 580 void qcow2_cache_entry_mark_dirty(BlockDriverState *bs, Qcow2Cache *c, 581 void *table); 582 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c); 583 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c, 584 Qcow2Cache *dependency); 585 void qcow2_cache_depends_on_flush(Qcow2Cache *c); 586 587 void qcow2_cache_clean_unused(BlockDriverState *bs, Qcow2Cache *c); 588 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c); 589 590 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset, 591 void **table); 592 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset, 593 void **table); 594 void qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table); 595 596 #endif 597