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 /* indicate that the refcount of the referenced cluster is exactly one. */
  57 #define QCOW_OFLAG_COPIED     (1ULL << 63)
  58 /* indicate that the cluster is compressed (they never have the copied flag) */
  59 #define QCOW_OFLAG_COMPRESSED (1ULL << 62)
  60 /* The cluster reads as all zeros */
  61 #define QCOW_OFLAG_ZERO (1ULL << 0)
  62
  63 #define MIN_CLUSTER_BITS 9
  64 #define MAX_CLUSTER_BITS 21
  65
  66 /* Must be at least 2 to cover COW */
  67 #define MIN_L2_CACHE_SIZE 2 /* clusters */
  68
  69 /* Must be at least 4 to cover all cases of refcount table growth */
  70 #define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */
  71
  72 /* Whichever is more */
  73 #define DEFAULT_L2_CACHE_CLUSTERS 8 /* clusters */
  74 #define DEFAULT_L2_CACHE_BYTE_SIZE 1048576 /* bytes */
  75
  76 /* The refblock cache needs only a fourth of the L2 cache size to cover as many
  77  * clusters */
  78 #define DEFAULT_L2_REFCOUNT_SIZE_RATIO 4
  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_REFCOUNT_CACHE_SIZE "refcount-cache-size"
 100 #define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval"
 101
 102 typedef struct QCowHeader {
 103     uint32_t magic;
 104     uint32_t version;
 105     uint64_t backing_file_offset;
 106     uint32_t backing_file_size;
 107     uint32_t cluster_bits;
 108     uint64_t size; /* in bytes */
 109     uint32_t crypt_method;
 110     uint32_t l1_size; /* XXX: save number of clusters instead ? */
 111     uint64_t l1_table_offset;
 112     uint64_t refcount_table_offset;
 113     uint32_t refcount_table_clusters;
 114     uint32_t nb_snapshots;
 115     uint64_t snapshots_offset;
 116
 117     /* The following fields are only valid for version >= 3 */
 118     uint64_t incompatible_features;
 119     uint64_t compatible_features;
 120     uint64_t autoclear_features;
 121
 122     uint32_t refcount_order;
 123     uint32_t header_length;
 124 } QEMU_PACKED QCowHeader;
 125
 126 typedef struct QEMU_PACKED QCowSnapshotHeader {
 127     /* header is 8 byte aligned */
 128     uint64_t l1_table_offset;
 129
 130     uint32_t l1_size;
 131     uint16_t id_str_size;
 132     uint16_t name_size;
 133
 134     uint32_t date_sec;
 135     uint32_t date_nsec;
 136
 137     uint64_t vm_clock_nsec;
 138
 139     uint32_t vm_state_size;
 140     uint32_t extra_data_size; /* for extension */
 141     /* extra data follows */
 142     /* id_str follows */
 143     /* name follows  */
 144 } QCowSnapshotHeader;
 145
 146 typedef struct QEMU_PACKED QCowSnapshotExtraData {
 147     uint64_t vm_state_size_large;
 148     uint64_t disk_size;
 149 } QCowSnapshotExtraData;
 150
 151
 152 typedef struct QCowSnapshot {
 153     uint64_t l1_table_offset;
 154     uint32_t l1_size;
 155     char *id_str;
 156     char *name;
 157     uint64_t disk_size;
 158     uint64_t vm_state_size;
 159     uint32_t date_sec;
 160     uint32_t date_nsec;
 161     uint64_t vm_clock_nsec;
 162 } QCowSnapshot;
 163
 164 struct Qcow2Cache;
 165 typedef struct Qcow2Cache Qcow2Cache;
 166
 167 typedef struct Qcow2CryptoHeaderExtension {
 168     uint64_t offset;
 169     uint64_t length;
 170 } QEMU_PACKED Qcow2CryptoHeaderExtension;
 171
 172 typedef struct Qcow2UnknownHeaderExtension {
 173     uint32_t magic;
 174     uint32_t len;
 175     QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
 176     uint8_t data[];
 177 } Qcow2UnknownHeaderExtension;
 178
 179 enum {
 180     QCOW2_FEAT_TYPE_INCOMPATIBLE    = 0,
 181     QCOW2_FEAT_TYPE_COMPATIBLE      = 1,
 182     QCOW2_FEAT_TYPE_AUTOCLEAR       = 2,
 183 };
 184
 185 /* Incompatible feature bits */
 186 enum {
 187     QCOW2_INCOMPAT_DIRTY_BITNR   = 0,
 188     QCOW2_INCOMPAT_CORRUPT_BITNR = 1,
 189     QCOW2_INCOMPAT_DIRTY         = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
 190     QCOW2_INCOMPAT_CORRUPT       = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
 191
 192     QCOW2_INCOMPAT_MASK          = QCOW2_INCOMPAT_DIRTY
 193                                  | QCOW2_INCOMPAT_CORRUPT,
 194 };
 195
 196 /* Compatible feature bits */
 197 enum {
 198     QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
 199     QCOW2_COMPAT_LAZY_REFCOUNTS       = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
 200
 201     QCOW2_COMPAT_FEAT_MASK            = QCOW2_COMPAT_LAZY_REFCOUNTS,
 202 };
 203
 204 enum qcow2_discard_type {
 205     QCOW2_DISCARD_NEVER = 0,
 206     QCOW2_DISCARD_ALWAYS,
 207     QCOW2_DISCARD_REQUEST,
 208     QCOW2_DISCARD_SNAPSHOT,
 209     QCOW2_DISCARD_OTHER,
 210     QCOW2_DISCARD_MAX
 211 };
 212
 213 typedef struct Qcow2Feature {
 214     uint8_t type;
 215     uint8_t bit;
 216     char    name[46];
 217 } QEMU_PACKED Qcow2Feature;
 218
 219 typedef struct Qcow2DiscardRegion {
 220     BlockDriverState *bs;
 221     uint64_t offset;
 222     uint64_t bytes;
 223     QTAILQ_ENTRY(Qcow2DiscardRegion) next;
 224 } Qcow2DiscardRegion;
 225
 226 typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
 227                                       uint64_t index);
 228 typedef void Qcow2SetRefcountFunc(void *refcount_array,
 229                                   uint64_t index, uint64_t value);
 230
 231 typedef struct BDRVQcow2State {
 232     int cluster_bits;
 233     int cluster_size;
 234     int cluster_sectors;
 235     int l2_bits;
 236     int l2_size;
 237     int l1_size;
 238     int l1_vm_state_index;
 239     int refcount_block_bits;
 240     int refcount_block_size;
 241     int csize_shift;
 242     int csize_mask;
 243     uint64_t cluster_offset_mask;
 244     uint64_t l1_table_offset;
 245     uint64_t *l1_table;
 246
 247     Qcow2Cache* l2_table_cache;
 248     Qcow2Cache* refcount_block_cache;
 249     QEMUTimer *cache_clean_timer;
 250     unsigned cache_clean_interval;
 251
 252     uint8_t *cluster_cache;
 253     uint8_t *cluster_data;
 254     uint64_t cluster_cache_offset;
 255     QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
 256
 257     uint64_t *refcount_table;
 258     uint64_t refcount_table_offset;
 259     uint32_t refcount_table_size;
 260     uint32_t max_refcount_table_index; /* Last used entry in refcount_table */
 261     uint64_t free_cluster_index;
 262     uint64_t free_byte_offset;
 263
 264     CoMutex lock;
 265
 266     Qcow2CryptoHeaderExtension crypto_header; /* QCow2 header extension */
 267     QCryptoBlockOpenOptions *crypto_opts; /* Disk encryption runtime options */
 268     QCryptoBlock *crypto; /* Disk encryption format driver */
 269     bool crypt_physical_offset; /* Whether to use virtual or physical offset
 270                                    for encryption initialization vector tweak */
 271     uint32_t crypt_method_header;
 272     uint64_t snapshots_offset;
 273     int snapshots_size;
 274     unsigned int nb_snapshots;
 275     QCowSnapshot *snapshots;
 276
 277     int flags;
 278     int qcow_version;
 279     bool use_lazy_refcounts;
 280     int refcount_order;
 281     int refcount_bits;
 282     uint64_t refcount_max;
 283
 284     Qcow2GetRefcountFunc *get_refcount;
 285     Qcow2SetRefcountFunc *set_refcount;
 286
 287     bool discard_passthrough[QCOW2_DISCARD_MAX];
 288
 289     int overlap_check; /* bitmask of Qcow2MetadataOverlap values */
 290     bool signaled_corruption;
 291
 292     uint64_t incompatible_features;
 293     uint64_t compatible_features;
 294     uint64_t autoclear_features;
 295
 296     size_t unknown_header_fields_size;
 297     void* unknown_header_fields;
 298     QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
 299     QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
 300     bool cache_discards;
 301
 302     /* Backing file path and format as stored in the image (this is not the
 303      * effective path/format, which may be the result of a runtime option
 304      * override) */
 305     char *image_backing_file;
 306     char *image_backing_format;
 307 } BDRVQcow2State;
 308
 309 typedef struct Qcow2COWRegion {
 310     /**
 311      * Offset of the COW region in bytes from the start of the first cluster
 312      * touched by the request.
 313      */
 314     unsigned    offset;
 315
 316     /** Number of bytes to copy */
 317     unsigned    nb_bytes;
 318 } Qcow2COWRegion;
 319
 320 /**
 321  * Describes an in-flight (part of a) write request that writes to clusters
 322  * that are not referenced in their L2 table yet.
 323  */
 324 typedef struct QCowL2Meta
 325 {
 326     /** Guest offset of the first newly allocated cluster */
 327     uint64_t offset;
 328
 329     /** Host offset of the first newly allocated cluster */
 330     uint64_t alloc_offset;
 331
 332     /** Number of newly allocated clusters */
 333     int nb_clusters;
 334
 335     /** Do not free the old clusters */
 336     bool keep_old_clusters;
 337
 338     /**
 339      * Requests that overlap with this allocation and wait to be restarted
 340      * when the allocating request has completed.
 341      */
 342     CoQueue dependent_requests;
 343
 344     /**
 345      * The COW Region between the start of the first allocated cluster and the
 346      * area the guest actually writes to.
 347      */
 348     Qcow2COWRegion cow_start;
 349
 350     /**
 351      * The COW Region between the area the guest actually writes to and the
 352      * end of the last allocated cluster.
 353      */
 354     Qcow2COWRegion cow_end;
 355
 356     /**
 357      * The I/O vector with the data from the actual guest write request.
 358      * If non-NULL, this is meant to be merged together with the data
 359      * from @cow_start and @cow_end into one single write operation.
 360      */
 361     QEMUIOVector *data_qiov;
 362
 363     /** Pointer to next L2Meta of the same write request */
 364     struct QCowL2Meta *next;
 365
 366     QLIST_ENTRY(QCowL2Meta) next_in_flight;
 367 } QCowL2Meta;
 368
 369 typedef enum QCow2ClusterType {
 370     QCOW2_CLUSTER_UNALLOCATED,
 371     QCOW2_CLUSTER_ZERO_PLAIN,
 372     QCOW2_CLUSTER_ZERO_ALLOC,
 373     QCOW2_CLUSTER_NORMAL,
 374     QCOW2_CLUSTER_COMPRESSED,
 375 } QCow2ClusterType;
 376
 377 typedef enum QCow2MetadataOverlap {
 378     QCOW2_OL_MAIN_HEADER_BITNR    = 0,
 379     QCOW2_OL_ACTIVE_L1_BITNR      = 1,
 380     QCOW2_OL_ACTIVE_L2_BITNR      = 2,
 381     QCOW2_OL_REFCOUNT_TABLE_BITNR = 3,
 382     QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4,
 383     QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5,
 384     QCOW2_OL_INACTIVE_L1_BITNR    = 6,
 385     QCOW2_OL_INACTIVE_L2_BITNR    = 7,
 386
 387     QCOW2_OL_MAX_BITNR            = 8,
 388
 389     QCOW2_OL_NONE           = 0,
 390     QCOW2_OL_MAIN_HEADER    = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
 391     QCOW2_OL_ACTIVE_L1      = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
 392     QCOW2_OL_ACTIVE_L2      = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
 393     QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
 394     QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
 395     QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
 396     QCOW2_OL_INACTIVE_L1    = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
 397     /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
 398      * reads. */
 399     QCOW2_OL_INACTIVE_L2    = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
 400 } QCow2MetadataOverlap;
 401
 402 /* Perform all overlap checks which can be done in constant time */
 403 #define QCOW2_OL_CONSTANT \
 404     (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
 405      QCOW2_OL_SNAPSHOT_TABLE)
 406
 407 /* Perform all overlap checks which don't require disk access */
 408 #define QCOW2_OL_CACHED \
 409     (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
 410      QCOW2_OL_INACTIVE_L1)
 411
 412 /* Perform all overlap checks */
 413 #define QCOW2_OL_ALL \
 414     (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
 415
 416 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
 417 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
 418 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
 419
 420 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
 421
 422 static inline int64_t start_of_cluster(BDRVQcow2State *s, int64_t offset)
 423 {
 424     return offset & ~(s->cluster_size - 1);
 425 }
 426
 427 static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset)
 428 {
 429     return offset & (s->cluster_size - 1);
 430 }
 431
 432 static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
 433 {
 434     return (size + (s->cluster_size - 1)) >> s->cluster_bits;
 435 }
 436
 437 static inline int64_t size_to_l1(BDRVQcow2State *s, int64_t size)
 438 {
 439     int shift = s->cluster_bits + s->l2_bits;
 440     return (size + (1ULL << shift) - 1) >> shift;
 441 }
 442
 443 static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset)
 444 {
 445     return (offset >> s->cluster_bits) & (s->l2_size - 1);
 446 }
 447
 448 static inline int64_t align_offset(int64_t offset, int n)
 449 {
 450     offset = (offset + n - 1) & ~(n - 1);
 451     return offset;
 452 }
 453
 454 static inline int64_t qcow2_vm_state_offset(BDRVQcow2State *s)
 455 {
 456     return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
 457 }
 458
 459 static inline uint64_t qcow2_max_refcount_clusters(BDRVQcow2State *s)
 460 {
 461     return QCOW_MAX_REFTABLE_SIZE >> s->cluster_bits;
 462 }
 463
 464 static inline QCow2ClusterType qcow2_get_cluster_type(uint64_t l2_entry)
 465 {
 466     if (l2_entry & QCOW_OFLAG_COMPRESSED) {
 467         return QCOW2_CLUSTER_COMPRESSED;
 468     } else if (l2_entry & QCOW_OFLAG_ZERO) {
 469         if (l2_entry & L2E_OFFSET_MASK) {
 470             return QCOW2_CLUSTER_ZERO_ALLOC;
 471         }
 472         return QCOW2_CLUSTER_ZERO_PLAIN;
 473     } else if (!(l2_entry & L2E_OFFSET_MASK)) {
 474         return QCOW2_CLUSTER_UNALLOCATED;
 475     } else {
 476         return QCOW2_CLUSTER_NORMAL;
 477     }
 478 }
 479
 480 /* Check whether refcounts are eager or lazy */
 481 static inline bool qcow2_need_accurate_refcounts(BDRVQcow2State *s)
 482 {
 483     return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
 484 }
 485
 486 static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
 487 {
 488     return m->offset + m->cow_start.offset;
 489 }
 490
 491 static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
 492 {
 493     return m->offset + m->cow_end.offset + m->cow_end.nb_bytes;
 494 }
 495
 496 static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2)
 497 {
 498     return r1 > r2 ? r1 - r2 : r2 - r1;
 499 }
 500
 501 /* qcow2.c functions */
 502 int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
 503                   int64_t sector_num, int nb_sectors);
 504
 505 int qcow2_mark_dirty(BlockDriverState *bs);
 506 int qcow2_mark_corrupt(BlockDriverState *bs);
 507 int qcow2_mark_consistent(BlockDriverState *bs);
 508 int qcow2_update_header(BlockDriverState *bs);
 509
 510 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
 511                              int64_t size, const char *message_format, ...)
 512                              GCC_FMT_ATTR(5, 6);
 513
 514 /* qcow2-refcount.c functions */
 515 int qcow2_refcount_init(BlockDriverState *bs);
 516 void qcow2_refcount_close(BlockDriverState *bs);
 517
 518 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index,
 519                        uint64_t *refcount);
 520
 521 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
 522                                   uint64_t addend, bool decrease,
 523                                   enum qcow2_discard_type type);
 524
 525 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
 526 int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
 527                                 int64_t nb_clusters);
 528 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
 529 void qcow2_free_clusters(BlockDriverState *bs,
 530                           int64_t offset, int64_t size,
 531                           enum qcow2_discard_type type);
 532 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
 533                              int nb_clusters, enum qcow2_discard_type type);
 534
 535 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
 536     int64_t l1_table_offset, int l1_size, int addend);
 537
 538 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 539                           BdrvCheckMode fix);
 540
 541 void qcow2_process_discards(BlockDriverState *bs, int ret);
 542
 543 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
 544                                  int64_t size);
 545 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
 546                                   int64_t size);
 547 int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
 548                              void **refcount_table,
 549                              int64_t *refcount_table_size,
 550                              int64_t offset, int64_t size);
 551
 552 int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
 553                                 BlockDriverAmendStatusCB *status_cb,
 554                                 void *cb_opaque, Error **errp);
 555
 556 /* qcow2-cluster.c functions */
 557 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
 558                         bool exact_size);
 559 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
 560 int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
 561 int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num,
 562                           uint8_t *buf, int nb_sectors, bool enc, Error **errp);
 563
 564 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
 565                              unsigned int *bytes, uint64_t *cluster_offset);
 566 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
 567                                unsigned int *bytes, uint64_t *host_offset,
 568                                QCowL2Meta **m);
 569 uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
 570                                          uint64_t offset,
 571                                          int compressed_size);
 572
 573 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
 574 int qcow2_cluster_discard(BlockDriverState *bs, uint64_t offset,
 575                           uint64_t bytes, enum qcow2_discard_type type,
 576                           bool full_discard);
 577 int qcow2_cluster_zeroize(BlockDriverState *bs, uint64_t offset,
 578                           uint64_t bytes, int flags);
 579
 580 int qcow2_expand_zero_clusters(BlockDriverState *bs,
 581                                BlockDriverAmendStatusCB *status_cb,
 582                                void *cb_opaque);
 583
 584 /* qcow2-snapshot.c functions */
 585 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
 586 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
 587 int qcow2_snapshot_delete(BlockDriverState *bs,
 588                           const char *snapshot_id,
 589                           const char *name,
 590                           Error **errp);
 591 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
 592 int qcow2_snapshot_load_tmp(BlockDriverState *bs,
 593                             const char *snapshot_id,
 594                             const char *name,
 595                             Error **errp);
 596
 597 void qcow2_free_snapshots(BlockDriverState *bs);
 598 int qcow2_read_snapshots(BlockDriverState *bs);
 599
 600 /* qcow2-cache.c functions */
 601 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables);
 602 int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
 603
 604 void qcow2_cache_entry_mark_dirty(BlockDriverState *bs, Qcow2Cache *c,
 605      void *table);
 606 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
 607 int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c);
 608 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
 609     Qcow2Cache *dependency);
 610 void qcow2_cache_depends_on_flush(Qcow2Cache *c);
 611
 612 void qcow2_cache_clean_unused(BlockDriverState *bs, Qcow2Cache *c);
 613 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c);
 614
 615 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 616     void **table);
 617 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 618     void **table);
 619 void qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
 620
 621 #endif