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/block.h" 29 #include "qemu/coroutine.h" 30 #include "qemu/units.h" 31 #include "block/block_int.h" 32 33 //#define DEBUG_ALLOC 34 //#define DEBUG_ALLOC2 35 //#define DEBUG_EXT 36 37 #define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb) 38 39 #define QCOW_CRYPT_NONE 0 40 #define QCOW_CRYPT_AES 1 41 #define QCOW_CRYPT_LUKS 2 42 43 #define QCOW_MAX_CRYPT_CLUSTERS 32 44 #define QCOW_MAX_SNAPSHOTS 65536 45 46 /* Field widths in qcow2 mean normal cluster offsets cannot reach 47 * 64PB; depending on cluster size, compressed clusters can have a 48 * smaller limit (64PB for up to 16k clusters, then ramps down to 49 * 512TB for 2M clusters). */ 50 #define QCOW_MAX_CLUSTER_OFFSET ((1ULL << 56) - 1) 51 52 /* 8 MB refcount table is enough for 2 PB images at 64k cluster size 53 * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */ 54 #define QCOW_MAX_REFTABLE_SIZE (8 * MiB) 55 56 /* 32 MB L1 table is enough for 2 PB images at 64k cluster size 57 * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */ 58 #define QCOW_MAX_L1_SIZE (32 * MiB) 59 60 /* Allow for an average of 1k per snapshot table entry, should be plenty of 61 * space for snapshot names and IDs */ 62 #define QCOW_MAX_SNAPSHOTS_SIZE (1024 * QCOW_MAX_SNAPSHOTS) 63 64 /* Maximum amount of extra data per snapshot table entry to accept */ 65 #define QCOW_MAX_SNAPSHOT_EXTRA_DATA 1024 66 67 /* Bitmap header extension constraints */ 68 #define QCOW2_MAX_BITMAPS 65535 69 #define QCOW2_MAX_BITMAP_DIRECTORY_SIZE (1024 * QCOW2_MAX_BITMAPS) 70 71 /* Maximum of parallel sub-request per guest request */ 72 #define QCOW2_MAX_WORKERS 8 73 74 /* indicate that the refcount of the referenced cluster is exactly one. */ 75 #define QCOW_OFLAG_COPIED (1ULL << 63) 76 /* indicate that the cluster is compressed (they never have the copied flag) */ 77 #define QCOW_OFLAG_COMPRESSED (1ULL << 62) 78 /* The cluster reads as all zeros */ 79 #define QCOW_OFLAG_ZERO (1ULL << 0) 80 81 #define MIN_CLUSTER_BITS 9 82 #define MAX_CLUSTER_BITS 21 83 84 /* Defined in the qcow2 spec (compressed cluster descriptor) */ 85 #define QCOW2_COMPRESSED_SECTOR_SIZE 512U 86 #define QCOW2_COMPRESSED_SECTOR_MASK (~(QCOW2_COMPRESSED_SECTOR_SIZE - 1ULL)) 87 88 /* Must be at least 2 to cover COW */ 89 #define MIN_L2_CACHE_SIZE 2 /* cache entries */ 90 91 /* Must be at least 4 to cover all cases of refcount table growth */ 92 #define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */ 93 94 #ifdef CONFIG_LINUX 95 #define DEFAULT_L2_CACHE_MAX_SIZE (32 * MiB) 96 #define DEFAULT_CACHE_CLEAN_INTERVAL 600 /* seconds */ 97 #else 98 #define DEFAULT_L2_CACHE_MAX_SIZE (8 * MiB) 99 /* Cache clean interval is currently available only on Linux, so must be 0 */ 100 #define DEFAULT_CACHE_CLEAN_INTERVAL 0 101 #endif 102 103 #define DEFAULT_CLUSTER_SIZE 65536 104 105 #define QCOW2_OPT_DATA_FILE "data-file" 106 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts" 107 #define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request" 108 #define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot" 109 #define QCOW2_OPT_DISCARD_OTHER "pass-discard-other" 110 #define QCOW2_OPT_OVERLAP "overlap-check" 111 #define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template" 112 #define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header" 113 #define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1" 114 #define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2" 115 #define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table" 116 #define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block" 117 #define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table" 118 #define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1" 119 #define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2" 120 #define QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY "overlap-check.bitmap-directory" 121 #define QCOW2_OPT_CACHE_SIZE "cache-size" 122 #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size" 123 #define QCOW2_OPT_L2_CACHE_ENTRY_SIZE "l2-cache-entry-size" 124 #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size" 125 #define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval" 126 127 typedef struct QCowHeader { 128 uint32_t magic; 129 uint32_t version; 130 uint64_t backing_file_offset; 131 uint32_t backing_file_size; 132 uint32_t cluster_bits; 133 uint64_t size; /* in bytes */ 134 uint32_t crypt_method; 135 uint32_t l1_size; /* XXX: save number of clusters instead ? */ 136 uint64_t l1_table_offset; 137 uint64_t refcount_table_offset; 138 uint32_t refcount_table_clusters; 139 uint32_t nb_snapshots; 140 uint64_t snapshots_offset; 141 142 /* The following fields are only valid for version >= 3 */ 143 uint64_t incompatible_features; 144 uint64_t compatible_features; 145 uint64_t autoclear_features; 146 147 uint32_t refcount_order; 148 uint32_t header_length; 149 } QEMU_PACKED QCowHeader; 150 151 typedef struct QEMU_PACKED QCowSnapshotHeader { 152 /* header is 8 byte aligned */ 153 uint64_t l1_table_offset; 154 155 uint32_t l1_size; 156 uint16_t id_str_size; 157 uint16_t name_size; 158 159 uint32_t date_sec; 160 uint32_t date_nsec; 161 162 uint64_t vm_clock_nsec; 163 164 uint32_t vm_state_size; 165 uint32_t extra_data_size; /* for extension */ 166 /* extra data follows */ 167 /* id_str follows */ 168 /* name follows */ 169 } QCowSnapshotHeader; 170 171 typedef struct QEMU_PACKED QCowSnapshotExtraData { 172 uint64_t vm_state_size_large; 173 uint64_t disk_size; 174 } QCowSnapshotExtraData; 175 176 177 typedef struct QCowSnapshot { 178 uint64_t l1_table_offset; 179 uint32_t l1_size; 180 char *id_str; 181 char *name; 182 uint64_t disk_size; 183 uint64_t vm_state_size; 184 uint32_t date_sec; 185 uint32_t date_nsec; 186 uint64_t vm_clock_nsec; 187 /* Size of all extra data, including QCowSnapshotExtraData if available */ 188 uint32_t extra_data_size; 189 /* Data beyond QCowSnapshotExtraData, if any */ 190 void *unknown_extra_data; 191 } QCowSnapshot; 192 193 struct Qcow2Cache; 194 typedef struct Qcow2Cache Qcow2Cache; 195 196 typedef struct Qcow2CryptoHeaderExtension { 197 uint64_t offset; 198 uint64_t length; 199 } QEMU_PACKED Qcow2CryptoHeaderExtension; 200 201 typedef struct Qcow2UnknownHeaderExtension { 202 uint32_t magic; 203 uint32_t len; 204 QLIST_ENTRY(Qcow2UnknownHeaderExtension) next; 205 uint8_t data[]; 206 } Qcow2UnknownHeaderExtension; 207 208 enum { 209 QCOW2_FEAT_TYPE_INCOMPATIBLE = 0, 210 QCOW2_FEAT_TYPE_COMPATIBLE = 1, 211 QCOW2_FEAT_TYPE_AUTOCLEAR = 2, 212 }; 213 214 /* Incompatible feature bits */ 215 enum { 216 QCOW2_INCOMPAT_DIRTY_BITNR = 0, 217 QCOW2_INCOMPAT_CORRUPT_BITNR = 1, 218 QCOW2_INCOMPAT_DATA_FILE_BITNR = 2, 219 QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR, 220 QCOW2_INCOMPAT_CORRUPT = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR, 221 QCOW2_INCOMPAT_DATA_FILE = 1 << QCOW2_INCOMPAT_DATA_FILE_BITNR, 222 223 QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY 224 | QCOW2_INCOMPAT_CORRUPT 225 | QCOW2_INCOMPAT_DATA_FILE, 226 }; 227 228 /* Compatible feature bits */ 229 enum { 230 QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0, 231 QCOW2_COMPAT_LAZY_REFCOUNTS = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR, 232 233 QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS, 234 }; 235 236 /* Autoclear feature bits */ 237 enum { 238 QCOW2_AUTOCLEAR_BITMAPS_BITNR = 0, 239 QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR = 1, 240 QCOW2_AUTOCLEAR_BITMAPS = 1 << QCOW2_AUTOCLEAR_BITMAPS_BITNR, 241 QCOW2_AUTOCLEAR_DATA_FILE_RAW = 1 << QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR, 242 243 QCOW2_AUTOCLEAR_MASK = QCOW2_AUTOCLEAR_BITMAPS 244 | QCOW2_AUTOCLEAR_DATA_FILE_RAW, 245 }; 246 247 enum qcow2_discard_type { 248 QCOW2_DISCARD_NEVER = 0, 249 QCOW2_DISCARD_ALWAYS, 250 QCOW2_DISCARD_REQUEST, 251 QCOW2_DISCARD_SNAPSHOT, 252 QCOW2_DISCARD_OTHER, 253 QCOW2_DISCARD_MAX 254 }; 255 256 typedef struct Qcow2Feature { 257 uint8_t type; 258 uint8_t bit; 259 char name[46]; 260 } QEMU_PACKED Qcow2Feature; 261 262 typedef struct Qcow2DiscardRegion { 263 BlockDriverState *bs; 264 uint64_t offset; 265 uint64_t bytes; 266 QTAILQ_ENTRY(Qcow2DiscardRegion) next; 267 } Qcow2DiscardRegion; 268 269 typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array, 270 uint64_t index); 271 typedef void Qcow2SetRefcountFunc(void *refcount_array, 272 uint64_t index, uint64_t value); 273 274 typedef struct Qcow2BitmapHeaderExt { 275 uint32_t nb_bitmaps; 276 uint32_t reserved32; 277 uint64_t bitmap_directory_size; 278 uint64_t bitmap_directory_offset; 279 } QEMU_PACKED Qcow2BitmapHeaderExt; 280 281 #define QCOW2_MAX_THREADS 4 282 283 typedef struct BDRVQcow2State { 284 int cluster_bits; 285 int cluster_size; 286 int l2_slice_size; 287 int l2_bits; 288 int l2_size; 289 int l1_size; 290 int l1_vm_state_index; 291 int refcount_block_bits; 292 int refcount_block_size; 293 int csize_shift; 294 int csize_mask; 295 uint64_t cluster_offset_mask; 296 uint64_t l1_table_offset; 297 uint64_t *l1_table; 298 299 Qcow2Cache* l2_table_cache; 300 Qcow2Cache* refcount_block_cache; 301 QEMUTimer *cache_clean_timer; 302 unsigned cache_clean_interval; 303 304 QLIST_HEAD(, QCowL2Meta) cluster_allocs; 305 306 uint64_t *refcount_table; 307 uint64_t refcount_table_offset; 308 uint32_t refcount_table_size; 309 uint32_t max_refcount_table_index; /* Last used entry in refcount_table */ 310 uint64_t free_cluster_index; 311 uint64_t free_byte_offset; 312 313 CoMutex lock; 314 315 Qcow2CryptoHeaderExtension crypto_header; /* QCow2 header extension */ 316 QCryptoBlockOpenOptions *crypto_opts; /* Disk encryption runtime options */ 317 QCryptoBlock *crypto; /* Disk encryption format driver */ 318 bool crypt_physical_offset; /* Whether to use virtual or physical offset 319 for encryption initialization vector tweak */ 320 uint32_t crypt_method_header; 321 uint64_t snapshots_offset; 322 int snapshots_size; 323 unsigned int nb_snapshots; 324 QCowSnapshot *snapshots; 325 326 uint32_t nb_bitmaps; 327 uint64_t bitmap_directory_size; 328 uint64_t bitmap_directory_offset; 329 330 int flags; 331 int qcow_version; 332 bool use_lazy_refcounts; 333 int refcount_order; 334 int refcount_bits; 335 uint64_t refcount_max; 336 337 Qcow2GetRefcountFunc *get_refcount; 338 Qcow2SetRefcountFunc *set_refcount; 339 340 bool discard_passthrough[QCOW2_DISCARD_MAX]; 341 342 int overlap_check; /* bitmask of Qcow2MetadataOverlap values */ 343 bool signaled_corruption; 344 345 uint64_t incompatible_features; 346 uint64_t compatible_features; 347 uint64_t autoclear_features; 348 349 size_t unknown_header_fields_size; 350 void* unknown_header_fields; 351 QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext; 352 QTAILQ_HEAD (, Qcow2DiscardRegion) discards; 353 bool cache_discards; 354 355 /* Backing file path and format as stored in the image (this is not the 356 * effective path/format, which may be the result of a runtime option 357 * override) */ 358 char *image_backing_file; 359 char *image_backing_format; 360 char *image_data_file; 361 362 CoQueue thread_task_queue; 363 int nb_threads; 364 365 BdrvChild *data_file; 366 367 bool metadata_preallocation_checked; 368 bool metadata_preallocation; 369 } BDRVQcow2State; 370 371 typedef struct Qcow2COWRegion { 372 /** 373 * Offset of the COW region in bytes from the start of the first cluster 374 * touched by the request. 375 */ 376 unsigned offset; 377 378 /** Number of bytes to copy */ 379 unsigned nb_bytes; 380 } Qcow2COWRegion; 381 382 /** 383 * Describes an in-flight (part of a) write request that writes to clusters 384 * that are not referenced in their L2 table yet. 385 */ 386 typedef struct QCowL2Meta 387 { 388 /** Guest offset of the first newly allocated cluster */ 389 uint64_t offset; 390 391 /** Host offset of the first newly allocated cluster */ 392 uint64_t alloc_offset; 393 394 /** Number of newly allocated clusters */ 395 int nb_clusters; 396 397 /** Do not free the old clusters */ 398 bool keep_old_clusters; 399 400 /** 401 * Requests that overlap with this allocation and wait to be restarted 402 * when the allocating request has completed. 403 */ 404 CoQueue dependent_requests; 405 406 /** 407 * The COW Region between the start of the first allocated cluster and the 408 * area the guest actually writes to. 409 */ 410 Qcow2COWRegion cow_start; 411 412 /** 413 * The COW Region between the area the guest actually writes to and the 414 * end of the last allocated cluster. 415 */ 416 Qcow2COWRegion cow_end; 417 418 /* 419 * Indicates that COW regions are already handled and do not require 420 * any more processing. 421 */ 422 bool skip_cow; 423 424 /** 425 * The I/O vector with the data from the actual guest write request. 426 * If non-NULL, this is meant to be merged together with the data 427 * from @cow_start and @cow_end into one single write operation. 428 */ 429 QEMUIOVector *data_qiov; 430 size_t data_qiov_offset; 431 432 /** Pointer to next L2Meta of the same write request */ 433 struct QCowL2Meta *next; 434 435 QLIST_ENTRY(QCowL2Meta) next_in_flight; 436 } QCowL2Meta; 437 438 typedef enum QCow2ClusterType { 439 QCOW2_CLUSTER_UNALLOCATED, 440 QCOW2_CLUSTER_ZERO_PLAIN, 441 QCOW2_CLUSTER_ZERO_ALLOC, 442 QCOW2_CLUSTER_NORMAL, 443 QCOW2_CLUSTER_COMPRESSED, 444 } QCow2ClusterType; 445 446 typedef enum QCow2MetadataOverlap { 447 QCOW2_OL_MAIN_HEADER_BITNR = 0, 448 QCOW2_OL_ACTIVE_L1_BITNR = 1, 449 QCOW2_OL_ACTIVE_L2_BITNR = 2, 450 QCOW2_OL_REFCOUNT_TABLE_BITNR = 3, 451 QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4, 452 QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5, 453 QCOW2_OL_INACTIVE_L1_BITNR = 6, 454 QCOW2_OL_INACTIVE_L2_BITNR = 7, 455 QCOW2_OL_BITMAP_DIRECTORY_BITNR = 8, 456 457 QCOW2_OL_MAX_BITNR = 9, 458 459 QCOW2_OL_NONE = 0, 460 QCOW2_OL_MAIN_HEADER = (1 << QCOW2_OL_MAIN_HEADER_BITNR), 461 QCOW2_OL_ACTIVE_L1 = (1 << QCOW2_OL_ACTIVE_L1_BITNR), 462 QCOW2_OL_ACTIVE_L2 = (1 << QCOW2_OL_ACTIVE_L2_BITNR), 463 QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR), 464 QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR), 465 QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR), 466 QCOW2_OL_INACTIVE_L1 = (1 << QCOW2_OL_INACTIVE_L1_BITNR), 467 /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv 468 * reads. */ 469 QCOW2_OL_INACTIVE_L2 = (1 << QCOW2_OL_INACTIVE_L2_BITNR), 470 QCOW2_OL_BITMAP_DIRECTORY = (1 << QCOW2_OL_BITMAP_DIRECTORY_BITNR), 471 } QCow2MetadataOverlap; 472 473 /* Perform all overlap checks which can be done in constant time */ 474 #define QCOW2_OL_CONSTANT \ 475 (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \ 476 QCOW2_OL_SNAPSHOT_TABLE | QCOW2_OL_BITMAP_DIRECTORY) 477 478 /* Perform all overlap checks which don't require disk access */ 479 #define QCOW2_OL_CACHED \ 480 (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \ 481 QCOW2_OL_INACTIVE_L1) 482 483 /* Perform all overlap checks */ 484 #define QCOW2_OL_ALL \ 485 (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2) 486 487 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL 488 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL 489 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL 490 491 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL 492 493 #define INV_OFFSET (-1ULL) 494 495 static inline bool has_data_file(BlockDriverState *bs) 496 { 497 BDRVQcow2State *s = bs->opaque; 498 return (s->data_file != bs->file); 499 } 500 501 static inline bool data_file_is_raw(BlockDriverState *bs) 502 { 503 BDRVQcow2State *s = bs->opaque; 504 return !!(s->autoclear_features & QCOW2_AUTOCLEAR_DATA_FILE_RAW); 505 } 506 507 static inline int64_t start_of_cluster(BDRVQcow2State *s, int64_t offset) 508 { 509 return offset & ~(s->cluster_size - 1); 510 } 511 512 static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset) 513 { 514 return offset & (s->cluster_size - 1); 515 } 516 517 static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size) 518 { 519 return (size + (s->cluster_size - 1)) >> s->cluster_bits; 520 } 521 522 static inline int64_t size_to_l1(BDRVQcow2State *s, int64_t size) 523 { 524 int shift = s->cluster_bits + s->l2_bits; 525 return (size + (1ULL << shift) - 1) >> shift; 526 } 527 528 static inline int offset_to_l1_index(BDRVQcow2State *s, uint64_t offset) 529 { 530 return offset >> (s->l2_bits + s->cluster_bits); 531 } 532 533 static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset) 534 { 535 return (offset >> s->cluster_bits) & (s->l2_size - 1); 536 } 537 538 static inline int offset_to_l2_slice_index(BDRVQcow2State *s, int64_t offset) 539 { 540 return (offset >> s->cluster_bits) & (s->l2_slice_size - 1); 541 } 542 543 static inline int64_t qcow2_vm_state_offset(BDRVQcow2State *s) 544 { 545 return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits); 546 } 547 548 static inline QCow2ClusterType qcow2_get_cluster_type(BlockDriverState *bs, 549 uint64_t l2_entry) 550 { 551 if (l2_entry & QCOW_OFLAG_COMPRESSED) { 552 return QCOW2_CLUSTER_COMPRESSED; 553 } else if (l2_entry & QCOW_OFLAG_ZERO) { 554 if (l2_entry & L2E_OFFSET_MASK) { 555 return QCOW2_CLUSTER_ZERO_ALLOC; 556 } 557 return QCOW2_CLUSTER_ZERO_PLAIN; 558 } else if (!(l2_entry & L2E_OFFSET_MASK)) { 559 /* Offset 0 generally means unallocated, but it is ambiguous with 560 * external data files because 0 is a valid offset there. However, all 561 * clusters in external data files always have refcount 1, so we can 562 * rely on QCOW_OFLAG_COPIED to disambiguate. */ 563 if (has_data_file(bs) && (l2_entry & QCOW_OFLAG_COPIED)) { 564 return QCOW2_CLUSTER_NORMAL; 565 } else { 566 return QCOW2_CLUSTER_UNALLOCATED; 567 } 568 } else { 569 return QCOW2_CLUSTER_NORMAL; 570 } 571 } 572 573 /* Check whether refcounts are eager or lazy */ 574 static inline bool qcow2_need_accurate_refcounts(BDRVQcow2State *s) 575 { 576 return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY); 577 } 578 579 static inline uint64_t l2meta_cow_start(QCowL2Meta *m) 580 { 581 return m->offset + m->cow_start.offset; 582 } 583 584 static inline uint64_t l2meta_cow_end(QCowL2Meta *m) 585 { 586 return m->offset + m->cow_end.offset + m->cow_end.nb_bytes; 587 } 588 589 static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2) 590 { 591 return r1 > r2 ? r1 - r2 : r2 - r1; 592 } 593 594 static inline 595 uint32_t offset_to_reftable_index(BDRVQcow2State *s, uint64_t offset) 596 { 597 return offset >> (s->refcount_block_bits + s->cluster_bits); 598 } 599 600 /* qcow2.c functions */ 601 int64_t qcow2_refcount_metadata_size(int64_t clusters, size_t cluster_size, 602 int refcount_order, bool generous_increase, 603 uint64_t *refblock_count); 604 605 int qcow2_mark_dirty(BlockDriverState *bs); 606 int qcow2_mark_corrupt(BlockDriverState *bs); 607 int qcow2_mark_consistent(BlockDriverState *bs); 608 int qcow2_update_header(BlockDriverState *bs); 609 610 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset, 611 int64_t size, const char *message_format, ...) 612 GCC_FMT_ATTR(5, 6); 613 614 int qcow2_validate_table(BlockDriverState *bs, uint64_t offset, 615 uint64_t entries, size_t entry_len, 616 int64_t max_size_bytes, const char *table_name, 617 Error **errp); 618 619 /* qcow2-refcount.c functions */ 620 int qcow2_refcount_init(BlockDriverState *bs); 621 void qcow2_refcount_close(BlockDriverState *bs); 622 623 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index, 624 uint64_t *refcount); 625 626 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index, 627 uint64_t addend, bool decrease, 628 enum qcow2_discard_type type); 629 630 int64_t qcow2_refcount_area(BlockDriverState *bs, uint64_t offset, 631 uint64_t additional_clusters, bool exact_size, 632 int new_refblock_index, 633 uint64_t new_refblock_offset); 634 635 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size); 636 int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset, 637 int64_t nb_clusters); 638 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size); 639 void qcow2_free_clusters(BlockDriverState *bs, 640 int64_t offset, int64_t size, 641 enum qcow2_discard_type type); 642 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry, 643 int nb_clusters, enum qcow2_discard_type type); 644 645 int qcow2_update_snapshot_refcount(BlockDriverState *bs, 646 int64_t l1_table_offset, int l1_size, int addend); 647 648 int coroutine_fn qcow2_flush_caches(BlockDriverState *bs); 649 int coroutine_fn qcow2_write_caches(BlockDriverState *bs); 650 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 651 BdrvCheckMode fix); 652 653 void qcow2_process_discards(BlockDriverState *bs, int ret); 654 655 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset, 656 int64_t size); 657 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset, 658 int64_t size, bool data_file); 659 int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res, 660 void **refcount_table, 661 int64_t *refcount_table_size, 662 int64_t offset, int64_t size); 663 664 int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order, 665 BlockDriverAmendStatusCB *status_cb, 666 void *cb_opaque, Error **errp); 667 int qcow2_shrink_reftable(BlockDriverState *bs); 668 int64_t qcow2_get_last_cluster(BlockDriverState *bs, int64_t size); 669 int qcow2_detect_metadata_preallocation(BlockDriverState *bs); 670 671 /* qcow2-cluster.c functions */ 672 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size, 673 bool exact_size); 674 int qcow2_shrink_l1_table(BlockDriverState *bs, uint64_t max_size); 675 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index); 676 int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num, 677 uint8_t *buf, int nb_sectors, bool enc, Error **errp); 678 679 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset, 680 unsigned int *bytes, uint64_t *cluster_offset); 681 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset, 682 unsigned int *bytes, uint64_t *host_offset, 683 QCowL2Meta **m); 684 int qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs, 685 uint64_t offset, 686 int compressed_size, 687 uint64_t *host_offset); 688 689 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m); 690 void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m); 691 int qcow2_cluster_discard(BlockDriverState *bs, uint64_t offset, 692 uint64_t bytes, enum qcow2_discard_type type, 693 bool full_discard); 694 int qcow2_cluster_zeroize(BlockDriverState *bs, uint64_t offset, 695 uint64_t bytes, int flags); 696 697 int qcow2_expand_zero_clusters(BlockDriverState *bs, 698 BlockDriverAmendStatusCB *status_cb, 699 void *cb_opaque); 700 701 /* qcow2-snapshot.c functions */ 702 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info); 703 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id); 704 int qcow2_snapshot_delete(BlockDriverState *bs, 705 const char *snapshot_id, 706 const char *name, 707 Error **errp); 708 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab); 709 int qcow2_snapshot_load_tmp(BlockDriverState *bs, 710 const char *snapshot_id, 711 const char *name, 712 Error **errp); 713 714 void qcow2_free_snapshots(BlockDriverState *bs); 715 int qcow2_read_snapshots(BlockDriverState *bs, Error **errp); 716 int qcow2_write_snapshots(BlockDriverState *bs); 717 718 int coroutine_fn qcow2_check_read_snapshot_table(BlockDriverState *bs, 719 BdrvCheckResult *result, 720 BdrvCheckMode fix); 721 int coroutine_fn qcow2_check_fix_snapshot_table(BlockDriverState *bs, 722 BdrvCheckResult *result, 723 BdrvCheckMode fix); 724 725 /* qcow2-cache.c functions */ 726 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables, 727 unsigned table_size); 728 int qcow2_cache_destroy(Qcow2Cache *c); 729 730 void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table); 731 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c); 732 int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c); 733 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c, 734 Qcow2Cache *dependency); 735 void qcow2_cache_depends_on_flush(Qcow2Cache *c); 736 737 void qcow2_cache_clean_unused(Qcow2Cache *c); 738 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c); 739 740 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset, 741 void **table); 742 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset, 743 void **table); 744 void qcow2_cache_put(Qcow2Cache *c, void **table); 745 void *qcow2_cache_is_table_offset(Qcow2Cache *c, uint64_t offset); 746 void qcow2_cache_discard(Qcow2Cache *c, void *table); 747 748 /* qcow2-bitmap.c functions */ 749 int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 750 void **refcount_table, 751 int64_t *refcount_table_size); 752 bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp); 753 Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs, 754 Error **errp); 755 int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp); 756 int qcow2_truncate_bitmaps_check(BlockDriverState *bs, Error **errp); 757 void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, 758 bool release_stored, Error **errp); 759 int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp); 760 bool qcow2_co_can_store_new_dirty_bitmap(BlockDriverState *bs, 761 const char *name, 762 uint32_t granularity, 763 Error **errp); 764 int qcow2_co_remove_persistent_dirty_bitmap(BlockDriverState *bs, 765 const char *name, 766 Error **errp); 767 768 ssize_t coroutine_fn 769 qcow2_co_compress(BlockDriverState *bs, void *dest, size_t dest_size, 770 const void *src, size_t src_size); 771 ssize_t coroutine_fn 772 qcow2_co_decompress(BlockDriverState *bs, void *dest, size_t dest_size, 773 const void *src, size_t src_size); 774 int coroutine_fn 775 qcow2_co_encrypt(BlockDriverState *bs, uint64_t host_offset, 776 uint64_t guest_offset, void *buf, size_t len); 777 int coroutine_fn 778 qcow2_co_decrypt(BlockDriverState *bs, uint64_t host_offset, 779 uint64_t guest_offset, void *buf, size_t len); 780 781 #endif 782