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 #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 QCOW_EXTL2_SUBCLUSTERS_PER_CLUSTER 32
  82
  83 /* The subcluster X [0..31] is allocated */
  84 #define QCOW_OFLAG_SUB_ALLOC(X)   (1ULL << (X))
  85 /* The subcluster X [0..31] reads as zeroes */
  86 #define QCOW_OFLAG_SUB_ZERO(X)    (QCOW_OFLAG_SUB_ALLOC(X) << 32)
  87 /* Subclusters [X, Y) (0 <= X <= Y <= 32) are allocated */
  88 #define QCOW_OFLAG_SUB_ALLOC_RANGE(X, Y) \
  89     (QCOW_OFLAG_SUB_ALLOC(Y) - QCOW_OFLAG_SUB_ALLOC(X))
  90 /* Subclusters [X, Y) (0 <= X <= Y <= 32) read as zeroes */
  91 #define QCOW_OFLAG_SUB_ZERO_RANGE(X, Y) \
  92     (QCOW_OFLAG_SUB_ALLOC_RANGE(X, Y) << 32)
  93 /* L2 entry bitmap with all allocation bits set */
  94 #define QCOW_L2_BITMAP_ALL_ALLOC  (QCOW_OFLAG_SUB_ALLOC_RANGE(0, 32))
  95 /* L2 entry bitmap with all "read as zeroes" bits set */
  96 #define QCOW_L2_BITMAP_ALL_ZEROES (QCOW_OFLAG_SUB_ZERO_RANGE(0, 32))
  97
  98 /* Size of normal and extended L2 entries */
  99 #define L2E_SIZE_NORMAL   (sizeof(uint64_t))
 100 #define L2E_SIZE_EXTENDED (sizeof(uint64_t) * 2)
 101
 102 /* Size of L1 table entries */
 103 #define L1E_SIZE (sizeof(uint64_t))
 104
 105 /* Size of reftable entries */
 106 #define REFTABLE_ENTRY_SIZE (sizeof(uint64_t))
 107
 108 #define MIN_CLUSTER_BITS 9
 109 #define MAX_CLUSTER_BITS 21
 110
 111 /* Defined in the qcow2 spec (compressed cluster descriptor) */
 112 #define QCOW2_COMPRESSED_SECTOR_SIZE 512U
 113 #define QCOW2_COMPRESSED_SECTOR_MASK (~(QCOW2_COMPRESSED_SECTOR_SIZE - 1ULL))
 114
 115 /* Must be at least 2 to cover COW */
 116 #define MIN_L2_CACHE_SIZE 2 /* cache entries */
 117
 118 /* Must be at least 4 to cover all cases of refcount table growth */
 119 #define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */
 120
 121 #ifdef CONFIG_LINUX
 122 #define DEFAULT_L2_CACHE_MAX_SIZE (32 * MiB)
 123 #define DEFAULT_CACHE_CLEAN_INTERVAL 600  /* seconds */
 124 #else
 125 #define DEFAULT_L2_CACHE_MAX_SIZE (8 * MiB)
 126 /* Cache clean interval is currently available only on Linux, so must be 0 */
 127 #define DEFAULT_CACHE_CLEAN_INTERVAL 0
 128 #endif
 129
 130 #define DEFAULT_CLUSTER_SIZE 65536
 131
 132 #define QCOW2_OPT_DATA_FILE "data-file"
 133 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts"
 134 #define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request"
 135 #define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot"
 136 #define QCOW2_OPT_DISCARD_OTHER "pass-discard-other"
 137 #define QCOW2_OPT_OVERLAP "overlap-check"
 138 #define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template"
 139 #define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header"
 140 #define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1"
 141 #define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2"
 142 #define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table"
 143 #define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block"
 144 #define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table"
 145 #define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1"
 146 #define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2"
 147 #define QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY "overlap-check.bitmap-directory"
 148 #define QCOW2_OPT_CACHE_SIZE "cache-size"
 149 #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size"
 150 #define QCOW2_OPT_L2_CACHE_ENTRY_SIZE "l2-cache-entry-size"
 151 #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size"
 152 #define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval"
 153
 154 typedef struct QCowHeader {
 155     uint32_t magic;
 156     uint32_t version;
 157     uint64_t backing_file_offset;
 158     uint32_t backing_file_size;
 159     uint32_t cluster_bits;
 160     uint64_t size; /* in bytes */
 161     uint32_t crypt_method;
 162     uint32_t l1_size; /* XXX: save number of clusters instead ? */
 163     uint64_t l1_table_offset;
 164     uint64_t refcount_table_offset;
 165     uint32_t refcount_table_clusters;
 166     uint32_t nb_snapshots;
 167     uint64_t snapshots_offset;
 168
 169     /* The following fields are only valid for version >= 3 */
 170     uint64_t incompatible_features;
 171     uint64_t compatible_features;
 172     uint64_t autoclear_features;
 173
 174     uint32_t refcount_order;
 175     uint32_t header_length;
 176
 177     /* Additional fields */
 178     uint8_t compression_type;
 179
 180     /* header must be a multiple of 8 */
 181     uint8_t padding[7];
 182 } QEMU_PACKED QCowHeader;
 183
 184 QEMU_BUILD_BUG_ON(!QEMU_IS_ALIGNED(sizeof(QCowHeader), 8));
 185
 186 typedef struct QEMU_PACKED QCowSnapshotHeader {
 187     /* header is 8 byte aligned */
 188     uint64_t l1_table_offset;
 189
 190     uint32_t l1_size;
 191     uint16_t id_str_size;
 192     uint16_t name_size;
 193
 194     uint32_t date_sec;
 195     uint32_t date_nsec;
 196
 197     uint64_t vm_clock_nsec;
 198
 199     uint32_t vm_state_size;
 200     uint32_t extra_data_size; /* for extension */
 201     /* extra data follows */
 202     /* id_str follows */
 203     /* name follows  */
 204 } QCowSnapshotHeader;
 205
 206 typedef struct QEMU_PACKED QCowSnapshotExtraData {
 207     uint64_t vm_state_size_large;
 208     uint64_t disk_size;
 209     uint64_t icount;
 210 } QCowSnapshotExtraData;
 211
 212
 213 typedef struct QCowSnapshot {
 214     uint64_t l1_table_offset;
 215     uint32_t l1_size;
 216     char *id_str;
 217     char *name;
 218     uint64_t disk_size;
 219     uint64_t vm_state_size;
 220     uint32_t date_sec;
 221     uint32_t date_nsec;
 222     uint64_t vm_clock_nsec;
 223     /* icount value for the moment when snapshot was taken */
 224     uint64_t icount;
 225     /* Size of all extra data, including QCowSnapshotExtraData if available */
 226     uint32_t extra_data_size;
 227     /* Data beyond QCowSnapshotExtraData, if any */
 228     void *unknown_extra_data;
 229 } QCowSnapshot;
 230
 231 struct Qcow2Cache;
 232 typedef struct Qcow2Cache Qcow2Cache;
 233
 234 typedef struct Qcow2CryptoHeaderExtension {
 235     uint64_t offset;
 236     uint64_t length;
 237 } QEMU_PACKED Qcow2CryptoHeaderExtension;
 238
 239 typedef struct Qcow2UnknownHeaderExtension {
 240     uint32_t magic;
 241     uint32_t len;
 242     QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
 243     uint8_t data[];
 244 } Qcow2UnknownHeaderExtension;
 245
 246 enum {
 247     QCOW2_FEAT_TYPE_INCOMPATIBLE    = 0,
 248     QCOW2_FEAT_TYPE_COMPATIBLE      = 1,
 249     QCOW2_FEAT_TYPE_AUTOCLEAR       = 2,
 250 };
 251
 252 /* Incompatible feature bits */
 253 enum {
 254     QCOW2_INCOMPAT_DIRTY_BITNR      = 0,
 255     QCOW2_INCOMPAT_CORRUPT_BITNR    = 1,
 256     QCOW2_INCOMPAT_DATA_FILE_BITNR  = 2,
 257     QCOW2_INCOMPAT_COMPRESSION_BITNR = 3,
 258     QCOW2_INCOMPAT_EXTL2_BITNR      = 4,
 259     QCOW2_INCOMPAT_DIRTY            = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
 260     QCOW2_INCOMPAT_CORRUPT          = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
 261     QCOW2_INCOMPAT_DATA_FILE        = 1 << QCOW2_INCOMPAT_DATA_FILE_BITNR,
 262     QCOW2_INCOMPAT_COMPRESSION      = 1 << QCOW2_INCOMPAT_COMPRESSION_BITNR,
 263     QCOW2_INCOMPAT_EXTL2            = 1 << QCOW2_INCOMPAT_EXTL2_BITNR,
 264
 265     QCOW2_INCOMPAT_MASK             = QCOW2_INCOMPAT_DIRTY
 266                                     | QCOW2_INCOMPAT_CORRUPT
 267                                     | QCOW2_INCOMPAT_DATA_FILE
 268                                     | QCOW2_INCOMPAT_COMPRESSION
 269                                     | QCOW2_INCOMPAT_EXTL2,
 270 };
 271
 272 /* Compatible feature bits */
 273 enum {
 274     QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
 275     QCOW2_COMPAT_LAZY_REFCOUNTS       = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
 276
 277     QCOW2_COMPAT_FEAT_MASK            = QCOW2_COMPAT_LAZY_REFCOUNTS,
 278 };
 279
 280 /* Autoclear feature bits */
 281 enum {
 282     QCOW2_AUTOCLEAR_BITMAPS_BITNR       = 0,
 283     QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR = 1,
 284     QCOW2_AUTOCLEAR_BITMAPS             = 1 << QCOW2_AUTOCLEAR_BITMAPS_BITNR,
 285     QCOW2_AUTOCLEAR_DATA_FILE_RAW       = 1 << QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR,
 286
 287     QCOW2_AUTOCLEAR_MASK                = QCOW2_AUTOCLEAR_BITMAPS
 288                                         | QCOW2_AUTOCLEAR_DATA_FILE_RAW,
 289 };
 290
 291 enum qcow2_discard_type {
 292     QCOW2_DISCARD_NEVER = 0,
 293     QCOW2_DISCARD_ALWAYS,
 294     QCOW2_DISCARD_REQUEST,
 295     QCOW2_DISCARD_SNAPSHOT,
 296     QCOW2_DISCARD_OTHER,
 297     QCOW2_DISCARD_MAX
 298 };
 299
 300 typedef struct Qcow2Feature {
 301     uint8_t type;
 302     uint8_t bit;
 303     char    name[46];
 304 } QEMU_PACKED Qcow2Feature;
 305
 306 typedef struct Qcow2DiscardRegion {
 307     BlockDriverState *bs;
 308     uint64_t offset;
 309     uint64_t bytes;
 310     QTAILQ_ENTRY(Qcow2DiscardRegion) next;
 311 } Qcow2DiscardRegion;
 312
 313 typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
 314                                       uint64_t index);
 315 typedef void Qcow2SetRefcountFunc(void *refcount_array,
 316                                   uint64_t index, uint64_t value);
 317
 318 typedef struct Qcow2BitmapHeaderExt {
 319     uint32_t nb_bitmaps;
 320     uint32_t reserved32;
 321     uint64_t bitmap_directory_size;
 322     uint64_t bitmap_directory_offset;
 323 } QEMU_PACKED Qcow2BitmapHeaderExt;
 324
 325 #define QCOW2_MAX_THREADS 4
 326
 327 typedef struct BDRVQcow2State {
 328     int cluster_bits;
 329     int cluster_size;
 330     int l2_slice_size;
 331     int subcluster_bits;
 332     int subcluster_size;
 333     int subclusters_per_cluster;
 334     int l2_bits;
 335     int l2_size;
 336     int l1_size;
 337     int l1_vm_state_index;
 338     int refcount_block_bits;
 339     int refcount_block_size;
 340     int csize_shift;
 341     int csize_mask;
 342     uint64_t cluster_offset_mask;
 343     uint64_t l1_table_offset;
 344     uint64_t *l1_table;
 345
 346     Qcow2Cache *l2_table_cache;
 347     Qcow2Cache *refcount_block_cache;
 348     QEMUTimer *cache_clean_timer;
 349     unsigned cache_clean_interval;
 350
 351     QLIST_HEAD(, QCowL2Meta) cluster_allocs;
 352
 353     uint64_t *refcount_table;
 354     uint64_t refcount_table_offset;
 355     uint32_t refcount_table_size;
 356     uint32_t max_refcount_table_index; /* Last used entry in refcount_table */
 357     uint64_t free_cluster_index;
 358     uint64_t free_byte_offset;
 359
 360     CoMutex lock;
 361
 362     Qcow2CryptoHeaderExtension crypto_header; /* QCow2 header extension */
 363     QCryptoBlockOpenOptions *crypto_opts; /* Disk encryption runtime options */
 364     QCryptoBlock *crypto; /* Disk encryption format driver */
 365     bool crypt_physical_offset; /* Whether to use virtual or physical offset
 366                                    for encryption initialization vector tweak */
 367     uint32_t crypt_method_header;
 368     uint64_t snapshots_offset;
 369     int snapshots_size;
 370     unsigned int nb_snapshots;
 371     QCowSnapshot *snapshots;
 372
 373     uint32_t nb_bitmaps;
 374     uint64_t bitmap_directory_size;
 375     uint64_t bitmap_directory_offset;
 376
 377     int flags;
 378     int qcow_version;
 379     bool use_lazy_refcounts;
 380     int refcount_order;
 381     int refcount_bits;
 382     uint64_t refcount_max;
 383
 384     Qcow2GetRefcountFunc *get_refcount;
 385     Qcow2SetRefcountFunc *set_refcount;
 386
 387     bool discard_passthrough[QCOW2_DISCARD_MAX];
 388
 389     int overlap_check; /* bitmask of Qcow2MetadataOverlap values */
 390     bool signaled_corruption;
 391
 392     uint64_t incompatible_features;
 393     uint64_t compatible_features;
 394     uint64_t autoclear_features;
 395
 396     size_t unknown_header_fields_size;
 397     void *unknown_header_fields;
 398     QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
 399     QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
 400     bool cache_discards;
 401
 402     /* Backing file path and format as stored in the image (this is not the
 403      * effective path/format, which may be the result of a runtime option
 404      * override) */
 405     char *image_backing_file;
 406     char *image_backing_format;
 407     char *image_data_file;
 408
 409     CoQueue thread_task_queue;
 410     int nb_threads;
 411
 412     BdrvChild *data_file;
 413
 414     bool metadata_preallocation_checked;
 415     bool metadata_preallocation;
 416     /*
 417      * Compression type used for the image. Default: 0 - ZLIB
 418      * The image compression type is set on image creation.
 419      * For now, the only way to change the compression type
 420      * is to convert the image with the desired compression type set.
 421      */
 422     Qcow2CompressionType compression_type;
 423 } BDRVQcow2State;
 424
 425 typedef struct Qcow2COWRegion {
 426     /**
 427      * Offset of the COW region in bytes from the start of the first cluster
 428      * touched by the request.
 429      */
 430     unsigned    offset;
 431
 432     /** Number of bytes to copy */
 433     unsigned    nb_bytes;
 434 } Qcow2COWRegion;
 435
 436 /**
 437  * Describes an in-flight (part of a) write request that writes to clusters
 438  * that need to have their L2 table entries updated (because they are
 439  * newly allocated or need changes in their L2 bitmaps)
 440  */
 441 typedef struct QCowL2Meta
 442 {
 443     /** Guest offset of the first updated cluster */
 444     uint64_t offset;
 445
 446     /** Host offset of the first updated cluster */
 447     uint64_t alloc_offset;
 448
 449     /** Number of updated clusters */
 450     int nb_clusters;
 451
 452     /** Do not free the old clusters */
 453     bool keep_old_clusters;
 454
 455     /**
 456      * Requests that overlap with this allocation and wait to be restarted
 457      * when the allocating request has completed.
 458      */
 459     CoQueue dependent_requests;
 460
 461     /**
 462      * The COW Region immediately before the area the guest actually
 463      * writes to. This (part of the) write request starts at
 464      * cow_start.offset + cow_start.nb_bytes.
 465      */
 466     Qcow2COWRegion cow_start;
 467
 468     /**
 469      * The COW Region immediately after the area the guest actually
 470      * writes to. This (part of the) write request ends at cow_end.offset
 471      * (which must always be set even when cow_end.nb_bytes is 0).
 472      */
 473     Qcow2COWRegion cow_end;
 474
 475     /*
 476      * Indicates that COW regions are already handled and do not require
 477      * any more processing.
 478      */
 479     bool skip_cow;
 480
 481     /**
 482      * Indicates that this is not a normal write request but a preallocation.
 483      * If the image has extended L2 entries this means that no new individual
 484      * subclusters will be marked as allocated in the L2 bitmap (but any
 485      * existing contents of that bitmap will be kept).
 486      */
 487     bool prealloc;
 488
 489     /**
 490      * The I/O vector with the data from the actual guest write request.
 491      * If non-NULL, this is meant to be merged together with the data
 492      * from @cow_start and @cow_end into one single write operation.
 493      */
 494     QEMUIOVector *data_qiov;
 495     size_t data_qiov_offset;
 496
 497     /** Pointer to next L2Meta of the same write request */
 498     struct QCowL2Meta *next;
 499
 500     QLIST_ENTRY(QCowL2Meta) next_in_flight;
 501 } QCowL2Meta;
 502
 503 /*
 504  * In images with standard L2 entries all clusters are treated as if
 505  * they had one subcluster so QCow2ClusterType and QCow2SubclusterType
 506  * can be mapped to each other and have the exact same meaning
 507  * (QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC cannot happen in these images).
 508  *
 509  * In images with extended L2 entries QCow2ClusterType refers to the
 510  * complete cluster and QCow2SubclusterType to each of the individual
 511  * subclusters, so there are several possible combinations:
 512  *
 513  *     |--------------+---------------------------|
 514  *     | Cluster type | Possible subcluster types |
 515  *     |--------------+---------------------------|
 516  *     | UNALLOCATED  |         UNALLOCATED_PLAIN |
 517  *     |              |                ZERO_PLAIN |
 518  *     |--------------+---------------------------|
 519  *     | NORMAL       |         UNALLOCATED_ALLOC |
 520  *     |              |                ZERO_ALLOC |
 521  *     |              |                    NORMAL |
 522  *     |--------------+---------------------------|
 523  *     | COMPRESSED   |                COMPRESSED |
 524  *     |--------------+---------------------------|
 525  *
 526  * QCOW2_SUBCLUSTER_INVALID means that the L2 entry is incorrect and
 527  * the image should be marked corrupt.
 528  */
 529
 530 typedef enum QCow2ClusterType {
 531     QCOW2_CLUSTER_UNALLOCATED,
 532     QCOW2_CLUSTER_ZERO_PLAIN,
 533     QCOW2_CLUSTER_ZERO_ALLOC,
 534     QCOW2_CLUSTER_NORMAL,
 535     QCOW2_CLUSTER_COMPRESSED,
 536 } QCow2ClusterType;
 537
 538 typedef enum QCow2SubclusterType {
 539     QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN,
 540     QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC,
 541     QCOW2_SUBCLUSTER_ZERO_PLAIN,
 542     QCOW2_SUBCLUSTER_ZERO_ALLOC,
 543     QCOW2_SUBCLUSTER_NORMAL,
 544     QCOW2_SUBCLUSTER_COMPRESSED,
 545     QCOW2_SUBCLUSTER_INVALID,
 546 } QCow2SubclusterType;
 547
 548 typedef enum QCow2MetadataOverlap {
 549     QCOW2_OL_MAIN_HEADER_BITNR      = 0,
 550     QCOW2_OL_ACTIVE_L1_BITNR        = 1,
 551     QCOW2_OL_ACTIVE_L2_BITNR        = 2,
 552     QCOW2_OL_REFCOUNT_TABLE_BITNR   = 3,
 553     QCOW2_OL_REFCOUNT_BLOCK_BITNR   = 4,
 554     QCOW2_OL_SNAPSHOT_TABLE_BITNR   = 5,
 555     QCOW2_OL_INACTIVE_L1_BITNR      = 6,
 556     QCOW2_OL_INACTIVE_L2_BITNR      = 7,
 557     QCOW2_OL_BITMAP_DIRECTORY_BITNR = 8,
 558
 559     QCOW2_OL_MAX_BITNR              = 9,
 560
 561     QCOW2_OL_NONE             = 0,
 562     QCOW2_OL_MAIN_HEADER      = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
 563     QCOW2_OL_ACTIVE_L1        = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
 564     QCOW2_OL_ACTIVE_L2        = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
 565     QCOW2_OL_REFCOUNT_TABLE   = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
 566     QCOW2_OL_REFCOUNT_BLOCK   = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
 567     QCOW2_OL_SNAPSHOT_TABLE   = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
 568     QCOW2_OL_INACTIVE_L1      = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
 569     /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
 570      * reads. */
 571     QCOW2_OL_INACTIVE_L2      = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
 572     QCOW2_OL_BITMAP_DIRECTORY = (1 << QCOW2_OL_BITMAP_DIRECTORY_BITNR),
 573 } QCow2MetadataOverlap;
 574
 575 /* Perform all overlap checks which can be done in constant time */
 576 #define QCOW2_OL_CONSTANT \
 577     (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
 578      QCOW2_OL_SNAPSHOT_TABLE | QCOW2_OL_BITMAP_DIRECTORY)
 579
 580 /* Perform all overlap checks which don't require disk access */
 581 #define QCOW2_OL_CACHED \
 582     (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
 583      QCOW2_OL_INACTIVE_L1)
 584
 585 /* Perform all overlap checks */
 586 #define QCOW2_OL_ALL \
 587     (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
 588
 589 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
 590 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
 591 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
 592
 593 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
 594
 595 #define INV_OFFSET (-1ULL)
 596
 597 static inline bool has_subclusters(BDRVQcow2State *s)
 598 {
 599     return s->incompatible_features & QCOW2_INCOMPAT_EXTL2;
 600 }
 601
 602 static inline size_t l2_entry_size(BDRVQcow2State *s)
 603 {
 604     return has_subclusters(s) ? L2E_SIZE_EXTENDED : L2E_SIZE_NORMAL;
 605 }
 606
 607 static inline uint64_t get_l2_entry(BDRVQcow2State *s, uint64_t *l2_slice,
 608                                     int idx)
 609 {
 610     idx *= l2_entry_size(s) / sizeof(uint64_t);
 611     return be64_to_cpu(l2_slice[idx]);
 612 }
 613
 614 static inline uint64_t get_l2_bitmap(BDRVQcow2State *s, uint64_t *l2_slice,
 615                                      int idx)
 616 {
 617     if (has_subclusters(s)) {
 618         idx *= l2_entry_size(s) / sizeof(uint64_t);
 619         return be64_to_cpu(l2_slice[idx + 1]);
 620     } else {
 621         return 0; /* For convenience only; this value has no meaning. */
 622     }
 623 }
 624
 625 static inline void set_l2_entry(BDRVQcow2State *s, uint64_t *l2_slice,
 626                                 int idx, uint64_t entry)
 627 {
 628     idx *= l2_entry_size(s) / sizeof(uint64_t);
 629     l2_slice[idx] = cpu_to_be64(entry);
 630 }
 631
 632 static inline void set_l2_bitmap(BDRVQcow2State *s, uint64_t *l2_slice,
 633                                  int idx, uint64_t bitmap)
 634 {
 635     assert(has_subclusters(s));
 636     idx *= l2_entry_size(s) / sizeof(uint64_t);
 637     l2_slice[idx + 1] = cpu_to_be64(bitmap);
 638 }
 639
 640 static inline bool has_data_file(BlockDriverState *bs)
 641 {
 642     BDRVQcow2State *s = bs->opaque;
 643     return (s->data_file != bs->file);
 644 }
 645
 646 static inline bool data_file_is_raw(BlockDriverState *bs)
 647 {
 648     BDRVQcow2State *s = bs->opaque;
 649     return !!(s->autoclear_features & QCOW2_AUTOCLEAR_DATA_FILE_RAW);
 650 }
 651
 652 static inline int64_t start_of_cluster(BDRVQcow2State *s, int64_t offset)
 653 {
 654     return offset & ~(s->cluster_size - 1);
 655 }
 656
 657 static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset)
 658 {
 659     return offset & (s->cluster_size - 1);
 660 }
 661
 662 static inline int64_t offset_into_subcluster(BDRVQcow2State *s, int64_t offset)
 663 {
 664     return offset & (s->subcluster_size - 1);
 665 }
 666
 667 static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
 668 {
 669     return (size + (s->cluster_size - 1)) >> s->cluster_bits;
 670 }
 671
 672 static inline uint64_t size_to_subclusters(BDRVQcow2State *s, uint64_t size)
 673 {
 674     return (size + (s->subcluster_size - 1)) >> s->subcluster_bits;
 675 }
 676
 677 static inline int64_t size_to_l1(BDRVQcow2State *s, int64_t size)
 678 {
 679     int shift = s->cluster_bits + s->l2_bits;
 680     return (size + (1ULL << shift) - 1) >> shift;
 681 }
 682
 683 static inline int offset_to_l1_index(BDRVQcow2State *s, uint64_t offset)
 684 {
 685     return offset >> (s->l2_bits + s->cluster_bits);
 686 }
 687
 688 static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset)
 689 {
 690     return (offset >> s->cluster_bits) & (s->l2_size - 1);
 691 }
 692
 693 static inline int offset_to_l2_slice_index(BDRVQcow2State *s, int64_t offset)
 694 {
 695     return (offset >> s->cluster_bits) & (s->l2_slice_size - 1);
 696 }
 697
 698 static inline int offset_to_sc_index(BDRVQcow2State *s, int64_t offset)
 699 {
 700     return (offset >> s->subcluster_bits) & (s->subclusters_per_cluster - 1);
 701 }
 702
 703 static inline int64_t qcow2_vm_state_offset(BDRVQcow2State *s)
 704 {
 705     return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
 706 }
 707
 708 static inline QCow2ClusterType qcow2_get_cluster_type(BlockDriverState *bs,
 709                                                       uint64_t l2_entry)
 710 {
 711     BDRVQcow2State *s = bs->opaque;
 712
 713     if (l2_entry & QCOW_OFLAG_COMPRESSED) {
 714         return QCOW2_CLUSTER_COMPRESSED;
 715     } else if ((l2_entry & QCOW_OFLAG_ZERO) && !has_subclusters(s)) {
 716         if (l2_entry & L2E_OFFSET_MASK) {
 717             return QCOW2_CLUSTER_ZERO_ALLOC;
 718         }
 719         return QCOW2_CLUSTER_ZERO_PLAIN;
 720     } else if (!(l2_entry & L2E_OFFSET_MASK)) {
 721         /* Offset 0 generally means unallocated, but it is ambiguous with
 722          * external data files because 0 is a valid offset there. However, all
 723          * clusters in external data files always have refcount 1, so we can
 724          * rely on QCOW_OFLAG_COPIED to disambiguate. */
 725         if (has_data_file(bs) && (l2_entry & QCOW_OFLAG_COPIED)) {
 726             return QCOW2_CLUSTER_NORMAL;
 727         } else {
 728             return QCOW2_CLUSTER_UNALLOCATED;
 729         }
 730     } else {
 731         return QCOW2_CLUSTER_NORMAL;
 732     }
 733 }
 734
 735 /*
 736  * In an image without subsclusters @l2_bitmap is ignored and
 737  * @sc_index must be 0.
 738  * Return QCOW2_SUBCLUSTER_INVALID if an invalid l2 entry is detected
 739  * (this checks the whole entry and bitmap, not only the bits related
 740  * to subcluster @sc_index).
 741  */
 742 static inline
 743 QCow2SubclusterType qcow2_get_subcluster_type(BlockDriverState *bs,
 744                                               uint64_t l2_entry,
 745                                               uint64_t l2_bitmap,
 746                                               unsigned sc_index)
 747 {
 748     BDRVQcow2State *s = bs->opaque;
 749     QCow2ClusterType type = qcow2_get_cluster_type(bs, l2_entry);
 750     assert(sc_index < s->subclusters_per_cluster);
 751
 752     if (has_subclusters(s)) {
 753         switch (type) {
 754         case QCOW2_CLUSTER_COMPRESSED:
 755             return QCOW2_SUBCLUSTER_COMPRESSED;
 756         case QCOW2_CLUSTER_NORMAL:
 757             if ((l2_bitmap >> 32) & l2_bitmap) {
 758                 return QCOW2_SUBCLUSTER_INVALID;
 759             } else if (l2_bitmap & QCOW_OFLAG_SUB_ZERO(sc_index)) {
 760                 return QCOW2_SUBCLUSTER_ZERO_ALLOC;
 761             } else if (l2_bitmap & QCOW_OFLAG_SUB_ALLOC(sc_index)) {
 762                 return QCOW2_SUBCLUSTER_NORMAL;
 763             } else {
 764                 return QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC;
 765             }
 766         case QCOW2_CLUSTER_UNALLOCATED:
 767             if (l2_bitmap & QCOW_L2_BITMAP_ALL_ALLOC) {
 768                 return QCOW2_SUBCLUSTER_INVALID;
 769             } else if (l2_bitmap & QCOW_OFLAG_SUB_ZERO(sc_index)) {
 770                 return QCOW2_SUBCLUSTER_ZERO_PLAIN;
 771             } else {
 772                 return QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN;
 773             }
 774         default:
 775             g_assert_not_reached();
 776         }
 777     } else {
 778         switch (type) {
 779         case QCOW2_CLUSTER_COMPRESSED:
 780             return QCOW2_SUBCLUSTER_COMPRESSED;
 781         case QCOW2_CLUSTER_ZERO_PLAIN:
 782             return QCOW2_SUBCLUSTER_ZERO_PLAIN;
 783         case QCOW2_CLUSTER_ZERO_ALLOC:
 784             return QCOW2_SUBCLUSTER_ZERO_ALLOC;
 785         case QCOW2_CLUSTER_NORMAL:
 786             return QCOW2_SUBCLUSTER_NORMAL;
 787         case QCOW2_CLUSTER_UNALLOCATED:
 788             return QCOW2_SUBCLUSTER_UNALLOCATED_PLAIN;
 789         default:
 790             g_assert_not_reached();
 791         }
 792     }
 793 }
 794
 795 static inline bool qcow2_cluster_is_allocated(QCow2ClusterType type)
 796 {
 797     return (type == QCOW2_CLUSTER_COMPRESSED || type == QCOW2_CLUSTER_NORMAL ||
 798             type == QCOW2_CLUSTER_ZERO_ALLOC);
 799 }
 800
 801 /* Check whether refcounts are eager or lazy */
 802 static inline bool qcow2_need_accurate_refcounts(BDRVQcow2State *s)
 803 {
 804     return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
 805 }
 806
 807 static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
 808 {
 809     return m->offset + m->cow_start.offset;
 810 }
 811
 812 static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
 813 {
 814     return m->offset + m->cow_end.offset + m->cow_end.nb_bytes;
 815 }
 816
 817 static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2)
 818 {
 819     return r1 > r2 ? r1 - r2 : r2 - r1;
 820 }
 821
 822 static inline
 823 uint32_t offset_to_reftable_index(BDRVQcow2State *s, uint64_t offset)
 824 {
 825     return offset >> (s->refcount_block_bits + s->cluster_bits);
 826 }
 827
 828 /* qcow2.c functions */
 829 int64_t qcow2_refcount_metadata_size(int64_t clusters, size_t cluster_size,
 830                                      int refcount_order, bool generous_increase,
 831                                      uint64_t *refblock_count);
 832
 833 int qcow2_mark_dirty(BlockDriverState *bs);
 834 int qcow2_mark_corrupt(BlockDriverState *bs);
 835 int qcow2_mark_consistent(BlockDriverState *bs);
 836 int qcow2_update_header(BlockDriverState *bs);
 837
 838 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
 839                              int64_t size, const char *message_format, ...)
 840                              GCC_FMT_ATTR(5, 6);
 841
 842 int qcow2_validate_table(BlockDriverState *bs, uint64_t offset,
 843                          uint64_t entries, size_t entry_len,
 844                          int64_t max_size_bytes, const char *table_name,
 845                          Error **errp);
 846
 847 /* qcow2-refcount.c functions */
 848 int qcow2_refcount_init(BlockDriverState *bs);
 849 void qcow2_refcount_close(BlockDriverState *bs);
 850
 851 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index,
 852                        uint64_t *refcount);
 853
 854 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
 855                                   uint64_t addend, bool decrease,
 856                                   enum qcow2_discard_type type);
 857
 858 int64_t qcow2_refcount_area(BlockDriverState *bs, uint64_t offset,
 859                             uint64_t additional_clusters, bool exact_size,
 860                             int new_refblock_index,
 861                             uint64_t new_refblock_offset);
 862
 863 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
 864 int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
 865                                 int64_t nb_clusters);
 866 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
 867 void qcow2_free_clusters(BlockDriverState *bs,
 868                           int64_t offset, int64_t size,
 869                           enum qcow2_discard_type type);
 870 void qcow2_free_any_cluster(BlockDriverState *bs, uint64_t l2_entry,
 871                             enum qcow2_discard_type type);
 872
 873 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
 874     int64_t l1_table_offset, int l1_size, int addend);
 875
 876 int coroutine_fn qcow2_flush_caches(BlockDriverState *bs);
 877 int coroutine_fn qcow2_write_caches(BlockDriverState *bs);
 878 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 879                           BdrvCheckMode fix);
 880
 881 void qcow2_process_discards(BlockDriverState *bs, int ret);
 882
 883 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
 884                                  int64_t size);
 885 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
 886                                   int64_t size, bool data_file);
 887 int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
 888                              void **refcount_table,
 889                              int64_t *refcount_table_size,
 890                              int64_t offset, int64_t size);
 891
 892 int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
 893                                 BlockDriverAmendStatusCB *status_cb,
 894                                 void *cb_opaque, Error **errp);
 895 int qcow2_shrink_reftable(BlockDriverState *bs);
 896 int64_t qcow2_get_last_cluster(BlockDriverState *bs, int64_t size);
 897 int qcow2_detect_metadata_preallocation(BlockDriverState *bs);
 898
 899 /* qcow2-cluster.c functions */
 900 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
 901                         bool exact_size);
 902 int qcow2_shrink_l1_table(BlockDriverState *bs, uint64_t max_size);
 903 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
 904 int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num,
 905                           uint8_t *buf, int nb_sectors, bool enc, Error **errp);
 906
 907 int qcow2_get_host_offset(BlockDriverState *bs, uint64_t offset,
 908                           unsigned int *bytes, uint64_t *host_offset,
 909                           QCow2SubclusterType *subcluster_type);
 910 int qcow2_alloc_host_offset(BlockDriverState *bs, uint64_t offset,
 911                             unsigned int *bytes, uint64_t *host_offset,
 912                             QCowL2Meta **m);
 913 int qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
 914                                           uint64_t offset,
 915                                           int compressed_size,
 916                                           uint64_t *host_offset);
 917
 918 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
 919 void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m);
 920 int qcow2_cluster_discard(BlockDriverState *bs, uint64_t offset,
 921                           uint64_t bytes, enum qcow2_discard_type type,
 922                           bool full_discard);
 923 int qcow2_subcluster_zeroize(BlockDriverState *bs, uint64_t offset,
 924                              uint64_t bytes, int flags);
 925
 926 int qcow2_expand_zero_clusters(BlockDriverState *bs,
 927                                BlockDriverAmendStatusCB *status_cb,
 928                                void *cb_opaque);
 929
 930 /* qcow2-snapshot.c functions */
 931 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
 932 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
 933 int qcow2_snapshot_delete(BlockDriverState *bs,
 934                           const char *snapshot_id,
 935                           const char *name,
 936                           Error **errp);
 937 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
 938 int qcow2_snapshot_load_tmp(BlockDriverState *bs,
 939                             const char *snapshot_id,
 940                             const char *name,
 941                             Error **errp);
 942
 943 void qcow2_free_snapshots(BlockDriverState *bs);
 944 int qcow2_read_snapshots(BlockDriverState *bs, Error **errp);
 945 int qcow2_write_snapshots(BlockDriverState *bs);
 946
 947 int coroutine_fn qcow2_check_read_snapshot_table(BlockDriverState *bs,
 948                                                  BdrvCheckResult *result,
 949                                                  BdrvCheckMode fix);
 950 int coroutine_fn qcow2_check_fix_snapshot_table(BlockDriverState *bs,
 951                                                 BdrvCheckResult *result,
 952                                                 BdrvCheckMode fix);
 953
 954 /* qcow2-cache.c functions */
 955 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
 956                                unsigned table_size);
 957 int qcow2_cache_destroy(Qcow2Cache *c);
 958
 959 void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
 960 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
 961 int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c);
 962 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
 963     Qcow2Cache *dependency);
 964 void qcow2_cache_depends_on_flush(Qcow2Cache *c);
 965
 966 void qcow2_cache_clean_unused(Qcow2Cache *c);
 967 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c);
 968
 969 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 970     void **table);
 971 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 972     void **table);
 973 void qcow2_cache_put(Qcow2Cache *c, void **table);
 974 void *qcow2_cache_is_table_offset(Qcow2Cache *c, uint64_t offset);
 975 void qcow2_cache_discard(Qcow2Cache *c, void *table);
 976
 977 /* qcow2-bitmap.c functions */
 978 int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 979                                   void **refcount_table,
 980                                   int64_t *refcount_table_size);
 981 bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp);
 982 Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs,
 983                                                 Error **errp);
 984 int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp);
 985 int qcow2_truncate_bitmaps_check(BlockDriverState *bs, Error **errp);
 986 void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
 987                                           bool release_stored, Error **errp);
 988 int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp);
 989 bool qcow2_co_can_store_new_dirty_bitmap(BlockDriverState *bs,
 990                                          const char *name,
 991                                          uint32_t granularity,
 992                                          Error **errp);
 993 int qcow2_co_remove_persistent_dirty_bitmap(BlockDriverState *bs,
 994                                             const char *name,
 995                                             Error **errp);
 996 bool qcow2_supports_persistent_dirty_bitmap(BlockDriverState *bs);
 997 uint64_t qcow2_get_persistent_dirty_bitmap_size(BlockDriverState *bs,
 998                                                 uint32_t cluster_size);
 999
1000 ssize_t coroutine_fn
1001 qcow2_co_compress(BlockDriverState *bs, void *dest, size_t dest_size,
1002                   const void *src, size_t src_size);
1003 ssize_t coroutine_fn
1004 qcow2_co_decompress(BlockDriverState *bs, void *dest, size_t dest_size,
1005                     const void *src, size_t src_size);
1006 int coroutine_fn
1007 qcow2_co_encrypt(BlockDriverState *bs, uint64_t host_offset,
1008                  uint64_t guest_offset, void *buf, size_t len);
1009 int coroutine_fn
1010 qcow2_co_decrypt(BlockDriverState *bs, uint64_t host_offset,
1011                  uint64_t guest_offset, void *buf, size_t len);
1012
1013 #endif