block/qcow2.h

   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
  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 #define QCOW_CRYPT_LUKS 2
  40
  41 #define QCOW_MAX_CRYPT_CLUSTERS 32
  42 #define QCOW_MAX_SNAPSHOTS 65536
  43
  44 /* 8 MB refcount table is enough for 2 PB images at 64k cluster size
  45  * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */
  46 #define QCOW_MAX_REFTABLE_SIZE 0x800000
  47
  48 /* 32 MB L1 table is enough for 2 PB images at 64k cluster size
  49  * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */
  50 #define QCOW_MAX_L1_SIZE 0x2000000
  51
  52 /* Allow for an average of 1k per snapshot table entry, should be plenty of
  53  * space for snapshot names and IDs */
  54 #define QCOW_MAX_SNAPSHOTS_SIZE (1024 * QCOW_MAX_SNAPSHOTS)
  55
  56 /* Bitmap header extension constraints */
  57 #define QCOW2_MAX_BITMAPS 65535
  58 #define QCOW2_MAX_BITMAP_DIRECTORY_SIZE (1024 * QCOW2_MAX_BITMAPS)
  59
  60 /* indicate that the refcount of the referenced cluster is exactly one. */
  61 #define QCOW_OFLAG_COPIED     (1ULL << 63)
  62 /* indicate that the cluster is compressed (they never have the copied flag) */
  63 #define QCOW_OFLAG_COMPRESSED (1ULL << 62)
  64 /* The cluster reads as all zeros */
  65 #define QCOW_OFLAG_ZERO (1ULL << 0)
  66
  67 #define MIN_CLUSTER_BITS 9
  68 #define MAX_CLUSTER_BITS 21
  69
  70 /* Must be at least 2 to cover COW */
  71 #define MIN_L2_CACHE_SIZE 2 /* cache entries */
  72
  73 /* Must be at least 4 to cover all cases of refcount table growth */
  74 #define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */
  75
  76 /* Whichever is more */
  77 #define DEFAULT_L2_CACHE_CLUSTERS 8 /* clusters */
  78 #define DEFAULT_L2_CACHE_BYTE_SIZE 1048576 /* bytes */
  79
  80 #define DEFAULT_CLUSTER_SIZE 65536
  81
  82
  83 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts"
  84 #define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request"
  85 #define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot"
  86 #define QCOW2_OPT_DISCARD_OTHER "pass-discard-other"
  87 #define QCOW2_OPT_OVERLAP "overlap-check"
  88 #define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template"
  89 #define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header"
  90 #define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1"
  91 #define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2"
  92 #define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table"
  93 #define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block"
  94 #define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table"
  95 #define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1"
  96 #define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2"
  97 #define QCOW2_OPT_CACHE_SIZE "cache-size"
  98 #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size"
  99 #define QCOW2_OPT_L2_CACHE_ENTRY_SIZE "l2-cache-entry-size"
 100 #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size"
 101 #define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval"
 102
 103 typedef struct QCowHeader {
 104     uint32_t magic;
 105     uint32_t version;
 106     uint64_t backing_file_offset;
 107     uint32_t backing_file_size;
 108     uint32_t cluster_bits;
 109     uint64_t size; /* in bytes */
 110     uint32_t crypt_method;
 111     uint32_t l1_size; /* XXX: save number of clusters instead ? */
 112     uint64_t l1_table_offset;
 113     uint64_t refcount_table_offset;
 114     uint32_t refcount_table_clusters;
 115     uint32_t nb_snapshots;
 116     uint64_t snapshots_offset;
 117
 118     /* The following fields are only valid for version >= 3 */
 119     uint64_t incompatible_features;
 120     uint64_t compatible_features;
 121     uint64_t autoclear_features;
 122
 123     uint32_t refcount_order;
 124     uint32_t header_length;
 125 } QEMU_PACKED QCowHeader;
 126
 127 typedef struct QEMU_PACKED QCowSnapshotHeader {
 128     /* header is 8 byte aligned */
 129     uint64_t l1_table_offset;
 130
 131     uint32_t l1_size;
 132     uint16_t id_str_size;
 133     uint16_t name_size;
 134
 135     uint32_t date_sec;
 136     uint32_t date_nsec;
 137
 138     uint64_t vm_clock_nsec;
 139
 140     uint32_t vm_state_size;
 141     uint32_t extra_data_size; /* for extension */
 142     /* extra data follows */
 143     /* id_str follows */
 144     /* name follows  */
 145 } QCowSnapshotHeader;
 146
 147 typedef struct QEMU_PACKED QCowSnapshotExtraData {
 148     uint64_t vm_state_size_large;
 149     uint64_t disk_size;
 150 } QCowSnapshotExtraData;
 151
 152
 153 typedef struct QCowSnapshot {
 154     uint64_t l1_table_offset;
 155     uint32_t l1_size;
 156     char *id_str;
 157     char *name;
 158     uint64_t disk_size;
 159     uint64_t vm_state_size;
 160     uint32_t date_sec;
 161     uint32_t date_nsec;
 162     uint64_t vm_clock_nsec;
 163 } QCowSnapshot;
 164
 165 struct Qcow2Cache;
 166 typedef struct Qcow2Cache Qcow2Cache;
 167
 168 typedef struct Qcow2CryptoHeaderExtension {
 169     uint64_t offset;
 170     uint64_t length;
 171 } QEMU_PACKED Qcow2CryptoHeaderExtension;
 172
 173 typedef struct Qcow2UnknownHeaderExtension {
 174     uint32_t magic;
 175     uint32_t len;
 176     QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
 177     uint8_t data[];
 178 } Qcow2UnknownHeaderExtension;
 179
 180 enum {
 181     QCOW2_FEAT_TYPE_INCOMPATIBLE    = 0,
 182     QCOW2_FEAT_TYPE_COMPATIBLE      = 1,
 183     QCOW2_FEAT_TYPE_AUTOCLEAR       = 2,
 184 };
 185
 186 /* Incompatible feature bits */
 187 enum {
 188     QCOW2_INCOMPAT_DIRTY_BITNR   = 0,
 189     QCOW2_INCOMPAT_CORRUPT_BITNR = 1,
 190     QCOW2_INCOMPAT_DIRTY         = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
 191     QCOW2_INCOMPAT_CORRUPT       = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
 192
 193     QCOW2_INCOMPAT_MASK          = QCOW2_INCOMPAT_DIRTY
 194                                  | QCOW2_INCOMPAT_CORRUPT,
 195 };
 196
 197 /* Compatible feature bits */
 198 enum {
 199     QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
 200     QCOW2_COMPAT_LAZY_REFCOUNTS       = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
 201
 202     QCOW2_COMPAT_FEAT_MASK            = QCOW2_COMPAT_LAZY_REFCOUNTS,
 203 };
 204
 205 /* Autoclear feature bits */
 206 enum {
 207     QCOW2_AUTOCLEAR_BITMAPS_BITNR = 0,
 208     QCOW2_AUTOCLEAR_BITMAPS       = 1 << QCOW2_AUTOCLEAR_BITMAPS_BITNR,
 209
 210     QCOW2_AUTOCLEAR_MASK          = QCOW2_AUTOCLEAR_BITMAPS,
 211 };
 212
 213 enum qcow2_discard_type {
 214     QCOW2_DISCARD_NEVER = 0,
 215     QCOW2_DISCARD_ALWAYS,
 216     QCOW2_DISCARD_REQUEST,
 217     QCOW2_DISCARD_SNAPSHOT,
 218     QCOW2_DISCARD_OTHER,
 219     QCOW2_DISCARD_MAX
 220 };
 221
 222 typedef struct Qcow2Feature {
 223     uint8_t type;
 224     uint8_t bit;
 225     char    name[46];
 226 } QEMU_PACKED Qcow2Feature;
 227
 228 typedef struct Qcow2DiscardRegion {
 229     BlockDriverState *bs;
 230     uint64_t offset;
 231     uint64_t bytes;
 232     QTAILQ_ENTRY(Qcow2DiscardRegion) next;
 233 } Qcow2DiscardRegion;
 234
 235 typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
 236                                       uint64_t index);
 237 typedef void Qcow2SetRefcountFunc(void *refcount_array,
 238                                   uint64_t index, uint64_t value);
 239
 240 typedef struct Qcow2BitmapHeaderExt {
 241     uint32_t nb_bitmaps;
 242     uint32_t reserved32;
 243     uint64_t bitmap_directory_size;
 244     uint64_t bitmap_directory_offset;
 245 } QEMU_PACKED Qcow2BitmapHeaderExt;
 246
 247 typedef struct BDRVQcow2State {
 248     int cluster_bits;
 249     int cluster_size;
 250     int cluster_sectors;
 251     int l2_slice_size;
 252     int l2_bits;
 253     int l2_size;
 254     int l1_size;
 255     int l1_vm_state_index;
 256     int refcount_block_bits;
 257     int refcount_block_size;
 258     int csize_shift;
 259     int csize_mask;
 260     uint64_t cluster_offset_mask;
 261     uint64_t l1_table_offset;
 262     uint64_t *l1_table;
 263
 264     Qcow2Cache* l2_table_cache;
 265     Qcow2Cache* refcount_block_cache;
 266     QEMUTimer *cache_clean_timer;
 267     unsigned cache_clean_interval;
 268
 269     uint8_t *cluster_cache;
 270     uint8_t *cluster_data;
 271     uint64_t cluster_cache_offset;
 272     QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
 273
 274     uint64_t *refcount_table;
 275     uint64_t refcount_table_offset;
 276     uint32_t refcount_table_size;
 277     uint32_t max_refcount_table_index; /* Last used entry in refcount_table */
 278     uint64_t free_cluster_index;
 279     uint64_t free_byte_offset;
 280
 281     CoMutex lock;
 282
 283     Qcow2CryptoHeaderExtension crypto_header; /* QCow2 header extension */
 284     QCryptoBlockOpenOptions *crypto_opts; /* Disk encryption runtime options */
 285     QCryptoBlock *crypto; /* Disk encryption format driver */
 286     bool crypt_physical_offset; /* Whether to use virtual or physical offset
 287                                    for encryption initialization vector tweak */
 288     uint32_t crypt_method_header;
 289     uint64_t snapshots_offset;
 290     int snapshots_size;
 291     unsigned int nb_snapshots;
 292     QCowSnapshot *snapshots;
 293
 294     uint32_t nb_bitmaps;
 295     uint64_t bitmap_directory_size;
 296     uint64_t bitmap_directory_offset;
 297     bool dirty_bitmaps_loaded;
 298
 299     int flags;
 300     int qcow_version;
 301     bool use_lazy_refcounts;
 302     int refcount_order;
 303     int refcount_bits;
 304     uint64_t refcount_max;
 305
 306     Qcow2GetRefcountFunc *get_refcount;
 307     Qcow2SetRefcountFunc *set_refcount;
 308
 309     bool discard_passthrough[QCOW2_DISCARD_MAX];
 310
 311     int overlap_check; /* bitmask of Qcow2MetadataOverlap values */
 312     bool signaled_corruption;
 313
 314     uint64_t incompatible_features;
 315     uint64_t compatible_features;
 316     uint64_t autoclear_features;
 317
 318     size_t unknown_header_fields_size;
 319     void* unknown_header_fields;
 320     QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
 321     QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
 322     bool cache_discards;
 323
 324     /* Backing file path and format as stored in the image (this is not the
 325      * effective path/format, which may be the result of a runtime option
 326      * override) */
 327     char *image_backing_file;
 328     char *image_backing_format;
 329
 330     CoQueue compress_wait_queue;
 331     int nb_compress_threads;
 332 } BDRVQcow2State;
 333
 334 typedef struct Qcow2COWRegion {
 335     /**
 336      * Offset of the COW region in bytes from the start of the first cluster
 337      * touched by the request.
 338      */
 339     unsigned    offset;
 340
 341     /** Number of bytes to copy */
 342     unsigned    nb_bytes;
 343 } Qcow2COWRegion;
 344
 345 /**
 346  * Describes an in-flight (part of a) write request that writes to clusters
 347  * that are not referenced in their L2 table yet.
 348  */
 349 typedef struct QCowL2Meta
 350 {
 351     /** Guest offset of the first newly allocated cluster */
 352     uint64_t offset;
 353
 354     /** Host offset of the first newly allocated cluster */
 355     uint64_t alloc_offset;
 356
 357     /** Number of newly allocated clusters */
 358     int nb_clusters;
 359
 360     /** Do not free the old clusters */
 361     bool keep_old_clusters;
 362
 363     /**
 364      * Requests that overlap with this allocation and wait to be restarted
 365      * when the allocating request has completed.
 366      */
 367     CoQueue dependent_requests;
 368
 369     /**
 370      * The COW Region between the start of the first allocated cluster and the
 371      * area the guest actually writes to.
 372      */
 373     Qcow2COWRegion cow_start;
 374
 375     /**
 376      * The COW Region between the area the guest actually writes to and the
 377      * end of the last allocated cluster.
 378      */
 379     Qcow2COWRegion cow_end;
 380
 381     /**
 382      * The I/O vector with the data from the actual guest write request.
 383      * If non-NULL, this is meant to be merged together with the data
 384      * from @cow_start and @cow_end into one single write operation.
 385      */
 386     QEMUIOVector *data_qiov;
 387
 388     /** Pointer to next L2Meta of the same write request */
 389     struct QCowL2Meta *next;
 390
 391     QLIST_ENTRY(QCowL2Meta) next_in_flight;
 392 } QCowL2Meta;
 393
 394 typedef enum QCow2ClusterType {
 395     QCOW2_CLUSTER_UNALLOCATED,
 396     QCOW2_CLUSTER_ZERO_PLAIN,
 397     QCOW2_CLUSTER_ZERO_ALLOC,
 398     QCOW2_CLUSTER_NORMAL,
 399     QCOW2_CLUSTER_COMPRESSED,
 400 } QCow2ClusterType;
 401
 402 typedef enum QCow2MetadataOverlap {
 403     QCOW2_OL_MAIN_HEADER_BITNR    = 0,
 404     QCOW2_OL_ACTIVE_L1_BITNR      = 1,
 405     QCOW2_OL_ACTIVE_L2_BITNR      = 2,
 406     QCOW2_OL_REFCOUNT_TABLE_BITNR = 3,
 407     QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4,
 408     QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5,
 409     QCOW2_OL_INACTIVE_L1_BITNR    = 6,
 410     QCOW2_OL_INACTIVE_L2_BITNR    = 7,
 411
 412     QCOW2_OL_MAX_BITNR            = 8,
 413
 414     QCOW2_OL_NONE           = 0,
 415     QCOW2_OL_MAIN_HEADER    = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
 416     QCOW2_OL_ACTIVE_L1      = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
 417     QCOW2_OL_ACTIVE_L2      = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
 418     QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
 419     QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
 420     QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
 421     QCOW2_OL_INACTIVE_L1    = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
 422     /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
 423      * reads. */
 424     QCOW2_OL_INACTIVE_L2    = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
 425 } QCow2MetadataOverlap;
 426
 427 /* Perform all overlap checks which can be done in constant time */
 428 #define QCOW2_OL_CONSTANT \
 429     (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
 430      QCOW2_OL_SNAPSHOT_TABLE)
 431
 432 /* Perform all overlap checks which don't require disk access */
 433 #define QCOW2_OL_CACHED \
 434     (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
 435      QCOW2_OL_INACTIVE_L1)
 436
 437 /* Perform all overlap checks */
 438 #define QCOW2_OL_ALL \
 439     (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
 440
 441 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
 442 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
 443 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
 444
 445 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
 446
 447 static inline int64_t start_of_cluster(BDRVQcow2State *s, int64_t offset)
 448 {
 449     return offset & ~(s->cluster_size - 1);
 450 }
 451
 452 static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset)
 453 {
 454     return offset & (s->cluster_size - 1);
 455 }
 456
 457 static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
 458 {
 459     return (size + (s->cluster_size - 1)) >> s->cluster_bits;
 460 }
 461
 462 static inline int64_t size_to_l1(BDRVQcow2State *s, int64_t size)
 463 {
 464     int shift = s->cluster_bits + s->l2_bits;
 465     return (size + (1ULL << shift) - 1) >> shift;
 466 }
 467
 468 static inline int offset_to_l1_index(BDRVQcow2State *s, uint64_t offset)
 469 {
 470     return offset >> (s->l2_bits + s->cluster_bits);
 471 }
 472
 473 static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset)
 474 {
 475     return (offset >> s->cluster_bits) & (s->l2_size - 1);
 476 }
 477
 478 static inline int offset_to_l2_slice_index(BDRVQcow2State *s, int64_t offset)
 479 {
 480     return (offset >> s->cluster_bits) & (s->l2_slice_size - 1);
 481 }
 482
 483 static inline int64_t qcow2_vm_state_offset(BDRVQcow2State *s)
 484 {
 485     return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
 486 }
 487
 488 static inline QCow2ClusterType qcow2_get_cluster_type(uint64_t l2_entry)
 489 {
 490     if (l2_entry & QCOW_OFLAG_COMPRESSED) {
 491         return QCOW2_CLUSTER_COMPRESSED;
 492     } else if (l2_entry & QCOW_OFLAG_ZERO) {
 493         if (l2_entry & L2E_OFFSET_MASK) {
 494             return QCOW2_CLUSTER_ZERO_ALLOC;
 495         }
 496         return QCOW2_CLUSTER_ZERO_PLAIN;
 497     } else if (!(l2_entry & L2E_OFFSET_MASK)) {
 498         return QCOW2_CLUSTER_UNALLOCATED;
 499     } else {
 500         return QCOW2_CLUSTER_NORMAL;
 501     }
 502 }
 503
 504 /* Check whether refcounts are eager or lazy */
 505 static inline bool qcow2_need_accurate_refcounts(BDRVQcow2State *s)
 506 {
 507     return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
 508 }
 509
 510 static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
 511 {
 512     return m->offset + m->cow_start.offset;
 513 }
 514
 515 static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
 516 {
 517     return m->offset + m->cow_end.offset + m->cow_end.nb_bytes;
 518 }
 519
 520 static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2)
 521 {
 522     return r1 > r2 ? r1 - r2 : r2 - r1;
 523 }
 524
 525 static inline
 526 uint32_t offset_to_reftable_index(BDRVQcow2State *s, uint64_t offset)
 527 {
 528     return offset >> (s->refcount_block_bits + s->cluster_bits);
 529 }
 530
 531 /* qcow2.c functions */
 532 int64_t qcow2_refcount_metadata_size(int64_t clusters, size_t cluster_size,
 533                                      int refcount_order, bool generous_increase,
 534                                      uint64_t *refblock_count);
 535
 536 int qcow2_mark_dirty(BlockDriverState *bs);
 537 int qcow2_mark_corrupt(BlockDriverState *bs);
 538 int qcow2_mark_consistent(BlockDriverState *bs);
 539 int qcow2_update_header(BlockDriverState *bs);
 540
 541 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
 542                              int64_t size, const char *message_format, ...)
 543                              GCC_FMT_ATTR(5, 6);
 544
 545 int qcow2_validate_table(BlockDriverState *bs, uint64_t offset,
 546                          uint64_t entries, size_t entry_len,
 547                          int64_t max_size_bytes, const char *table_name,
 548                          Error **errp);
 549
 550 /* qcow2-refcount.c functions */
 551 int qcow2_refcount_init(BlockDriverState *bs);
 552 void qcow2_refcount_close(BlockDriverState *bs);
 553
 554 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index,
 555                        uint64_t *refcount);
 556
 557 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
 558                                   uint64_t addend, bool decrease,
 559                                   enum qcow2_discard_type type);
 560
 561 int64_t qcow2_refcount_area(BlockDriverState *bs, uint64_t offset,
 562                             uint64_t additional_clusters, bool exact_size,
 563                             int new_refblock_index,
 564                             uint64_t new_refblock_offset);
 565
 566 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
 567 int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
 568                                 int64_t nb_clusters);
 569 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
 570 void qcow2_free_clusters(BlockDriverState *bs,
 571                           int64_t offset, int64_t size,
 572                           enum qcow2_discard_type type);
 573 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
 574                              int nb_clusters, enum qcow2_discard_type type);
 575
 576 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
 577     int64_t l1_table_offset, int l1_size, int addend);
 578
 579 int coroutine_fn qcow2_flush_caches(BlockDriverState *bs);
 580 int coroutine_fn qcow2_write_caches(BlockDriverState *bs);
 581 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 582                           BdrvCheckMode fix);
 583
 584 void qcow2_process_discards(BlockDriverState *bs, int ret);
 585
 586 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
 587                                  int64_t size);
 588 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
 589                                   int64_t size);
 590 int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
 591                              void **refcount_table,
 592                              int64_t *refcount_table_size,
 593                              int64_t offset, int64_t size);
 594
 595 int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
 596                                 BlockDriverAmendStatusCB *status_cb,
 597                                 void *cb_opaque, Error **errp);
 598 int qcow2_shrink_reftable(BlockDriverState *bs);
 599 int64_t qcow2_get_last_cluster(BlockDriverState *bs, int64_t size);
 600
 601 /* qcow2-cluster.c functions */
 602 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
 603                         bool exact_size);
 604 int qcow2_shrink_l1_table(BlockDriverState *bs, uint64_t max_size);
 605 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
 606 int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
 607 int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num,
 608                           uint8_t *buf, int nb_sectors, bool enc, Error **errp);
 609
 610 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
 611                              unsigned int *bytes, uint64_t *cluster_offset);
 612 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
 613                                unsigned int *bytes, uint64_t *host_offset,
 614                                QCowL2Meta **m);
 615 uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
 616                                          uint64_t offset,
 617                                          int compressed_size);
 618
 619 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
 620 void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m);
 621 int qcow2_cluster_discard(BlockDriverState *bs, uint64_t offset,
 622                           uint64_t bytes, enum qcow2_discard_type type,
 623                           bool full_discard);
 624 int qcow2_cluster_zeroize(BlockDriverState *bs, uint64_t offset,
 625                           uint64_t bytes, int flags);
 626
 627 int qcow2_expand_zero_clusters(BlockDriverState *bs,
 628                                BlockDriverAmendStatusCB *status_cb,
 629                                void *cb_opaque);
 630
 631 /* qcow2-snapshot.c functions */
 632 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
 633 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
 634 int qcow2_snapshot_delete(BlockDriverState *bs,
 635                           const char *snapshot_id,
 636                           const char *name,
 637                           Error **errp);
 638 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
 639 int qcow2_snapshot_load_tmp(BlockDriverState *bs,
 640                             const char *snapshot_id,
 641                             const char *name,
 642                             Error **errp);
 643
 644 void qcow2_free_snapshots(BlockDriverState *bs);
 645 int qcow2_read_snapshots(BlockDriverState *bs);
 646
 647 /* qcow2-cache.c functions */
 648 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
 649                                unsigned table_size);
 650 int qcow2_cache_destroy(Qcow2Cache *c);
 651
 652 void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
 653 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
 654 int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c);
 655 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
 656     Qcow2Cache *dependency);
 657 void qcow2_cache_depends_on_flush(Qcow2Cache *c);
 658
 659 void qcow2_cache_clean_unused(Qcow2Cache *c);
 660 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c);
 661
 662 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 663     void **table);
 664 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 665     void **table);
 666 void qcow2_cache_put(Qcow2Cache *c, void **table);
 667 void *qcow2_cache_is_table_offset(Qcow2Cache *c, uint64_t offset);
 668 void qcow2_cache_discard(Qcow2Cache *c, void *table);
 669
 670 /* qcow2-bitmap.c functions */
 671 int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 672                                   void **refcount_table,
 673                                   int64_t *refcount_table_size);
 674 bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp);
 675 int qcow2_reopen_bitmaps_rw_hint(BlockDriverState *bs, bool *header_updated,
 676                                  Error **errp);
 677 int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp);
 678 void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp);
 679 int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp);
 680 bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs,
 681                                       const char *name,
 682                                       uint32_t granularity,
 683                                       Error **errp);
 684 void qcow2_remove_persistent_dirty_bitmap(BlockDriverState *bs,
 685                                           const char *name,
 686                                           Error **errp);
 687
 688 #endif