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_OVERLAP_BITMAP_DIRECTORY "overlap-check.bitmap-directory"
  98 #define QCOW2_OPT_CACHE_SIZE "cache-size"
  99 #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size"
 100 #define QCOW2_OPT_L2_CACHE_ENTRY_SIZE "l2-cache-entry-size"
 101 #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size"
 102 #define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval"
 103
 104 typedef struct QCowHeader {
 105     uint32_t magic;
 106     uint32_t version;
 107     uint64_t backing_file_offset;
 108     uint32_t backing_file_size;
 109     uint32_t cluster_bits;
 110     uint64_t size; /* in bytes */
 111     uint32_t crypt_method;
 112     uint32_t l1_size; /* XXX: save number of clusters instead ? */
 113     uint64_t l1_table_offset;
 114     uint64_t refcount_table_offset;
 115     uint32_t refcount_table_clusters;
 116     uint32_t nb_snapshots;
 117     uint64_t snapshots_offset;
 118
 119     /* The following fields are only valid for version >= 3 */
 120     uint64_t incompatible_features;
 121     uint64_t compatible_features;
 122     uint64_t autoclear_features;
 123
 124     uint32_t refcount_order;
 125     uint32_t header_length;
 126 } QEMU_PACKED QCowHeader;
 127
 128 typedef struct QEMU_PACKED QCowSnapshotHeader {
 129     /* header is 8 byte aligned */
 130     uint64_t l1_table_offset;
 131
 132     uint32_t l1_size;
 133     uint16_t id_str_size;
 134     uint16_t name_size;
 135
 136     uint32_t date_sec;
 137     uint32_t date_nsec;
 138
 139     uint64_t vm_clock_nsec;
 140
 141     uint32_t vm_state_size;
 142     uint32_t extra_data_size; /* for extension */
 143     /* extra data follows */
 144     /* id_str follows */
 145     /* name follows  */
 146 } QCowSnapshotHeader;
 147
 148 typedef struct QEMU_PACKED QCowSnapshotExtraData {
 149     uint64_t vm_state_size_large;
 150     uint64_t disk_size;
 151 } QCowSnapshotExtraData;
 152
 153
 154 typedef struct QCowSnapshot {
 155     uint64_t l1_table_offset;
 156     uint32_t l1_size;
 157     char *id_str;
 158     char *name;
 159     uint64_t disk_size;
 160     uint64_t vm_state_size;
 161     uint32_t date_sec;
 162     uint32_t date_nsec;
 163     uint64_t vm_clock_nsec;
 164 } QCowSnapshot;
 165
 166 struct Qcow2Cache;
 167 typedef struct Qcow2Cache Qcow2Cache;
 168
 169 typedef struct Qcow2CryptoHeaderExtension {
 170     uint64_t offset;
 171     uint64_t length;
 172 } QEMU_PACKED Qcow2CryptoHeaderExtension;
 173
 174 typedef struct Qcow2UnknownHeaderExtension {
 175     uint32_t magic;
 176     uint32_t len;
 177     QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
 178     uint8_t data[];
 179 } Qcow2UnknownHeaderExtension;
 180
 181 enum {
 182     QCOW2_FEAT_TYPE_INCOMPATIBLE    = 0,
 183     QCOW2_FEAT_TYPE_COMPATIBLE      = 1,
 184     QCOW2_FEAT_TYPE_AUTOCLEAR       = 2,
 185 };
 186
 187 /* Incompatible feature bits */
 188 enum {
 189     QCOW2_INCOMPAT_DIRTY_BITNR   = 0,
 190     QCOW2_INCOMPAT_CORRUPT_BITNR = 1,
 191     QCOW2_INCOMPAT_DIRTY         = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
 192     QCOW2_INCOMPAT_CORRUPT       = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
 193
 194     QCOW2_INCOMPAT_MASK          = QCOW2_INCOMPAT_DIRTY
 195                                  | QCOW2_INCOMPAT_CORRUPT,
 196 };
 197
 198 /* Compatible feature bits */
 199 enum {
 200     QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
 201     QCOW2_COMPAT_LAZY_REFCOUNTS       = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
 202
 203     QCOW2_COMPAT_FEAT_MASK            = QCOW2_COMPAT_LAZY_REFCOUNTS,
 204 };
 205
 206 /* Autoclear feature bits */
 207 enum {
 208     QCOW2_AUTOCLEAR_BITMAPS_BITNR = 0,
 209     QCOW2_AUTOCLEAR_BITMAPS       = 1 << QCOW2_AUTOCLEAR_BITMAPS_BITNR,
 210
 211     QCOW2_AUTOCLEAR_MASK          = QCOW2_AUTOCLEAR_BITMAPS,
 212 };
 213
 214 enum qcow2_discard_type {
 215     QCOW2_DISCARD_NEVER = 0,
 216     QCOW2_DISCARD_ALWAYS,
 217     QCOW2_DISCARD_REQUEST,
 218     QCOW2_DISCARD_SNAPSHOT,
 219     QCOW2_DISCARD_OTHER,
 220     QCOW2_DISCARD_MAX
 221 };
 222
 223 typedef struct Qcow2Feature {
 224     uint8_t type;
 225     uint8_t bit;
 226     char    name[46];
 227 } QEMU_PACKED Qcow2Feature;
 228
 229 typedef struct Qcow2DiscardRegion {
 230     BlockDriverState *bs;
 231     uint64_t offset;
 232     uint64_t bytes;
 233     QTAILQ_ENTRY(Qcow2DiscardRegion) next;
 234 } Qcow2DiscardRegion;
 235
 236 typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
 237                                       uint64_t index);
 238 typedef void Qcow2SetRefcountFunc(void *refcount_array,
 239                                   uint64_t index, uint64_t value);
 240
 241 typedef struct Qcow2BitmapHeaderExt {
 242     uint32_t nb_bitmaps;
 243     uint32_t reserved32;
 244     uint64_t bitmap_directory_size;
 245     uint64_t bitmap_directory_offset;
 246 } QEMU_PACKED Qcow2BitmapHeaderExt;
 247
 248 typedef struct BDRVQcow2State {
 249     int cluster_bits;
 250     int cluster_size;
 251     int cluster_sectors;
 252     int l2_slice_size;
 253     int l2_bits;
 254     int l2_size;
 255     int l1_size;
 256     int l1_vm_state_index;
 257     int refcount_block_bits;
 258     int refcount_block_size;
 259     int csize_shift;
 260     int csize_mask;
 261     uint64_t cluster_offset_mask;
 262     uint64_t l1_table_offset;
 263     uint64_t *l1_table;
 264
 265     Qcow2Cache* l2_table_cache;
 266     Qcow2Cache* refcount_block_cache;
 267     QEMUTimer *cache_clean_timer;
 268     unsigned cache_clean_interval;
 269
 270     uint8_t *cluster_cache;
 271     uint8_t *cluster_data;
 272     uint64_t cluster_cache_offset;
 273     QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
 274
 275     uint64_t *refcount_table;
 276     uint64_t refcount_table_offset;
 277     uint32_t refcount_table_size;
 278     uint32_t max_refcount_table_index; /* Last used entry in refcount_table */
 279     uint64_t free_cluster_index;
 280     uint64_t free_byte_offset;
 281
 282     CoMutex lock;
 283
 284     Qcow2CryptoHeaderExtension crypto_header; /* QCow2 header extension */
 285     QCryptoBlockOpenOptions *crypto_opts; /* Disk encryption runtime options */
 286     QCryptoBlock *crypto; /* Disk encryption format driver */
 287     bool crypt_physical_offset; /* Whether to use virtual or physical offset
 288                                    for encryption initialization vector tweak */
 289     uint32_t crypt_method_header;
 290     uint64_t snapshots_offset;
 291     int snapshots_size;
 292     unsigned int nb_snapshots;
 293     QCowSnapshot *snapshots;
 294
 295     uint32_t nb_bitmaps;
 296     uint64_t bitmap_directory_size;
 297     uint64_t bitmap_directory_offset;
 298     bool dirty_bitmaps_loaded;
 299
 300     int flags;
 301     int qcow_version;
 302     bool use_lazy_refcounts;
 303     int refcount_order;
 304     int refcount_bits;
 305     uint64_t refcount_max;
 306
 307     Qcow2GetRefcountFunc *get_refcount;
 308     Qcow2SetRefcountFunc *set_refcount;
 309
 310     bool discard_passthrough[QCOW2_DISCARD_MAX];
 311
 312     int overlap_check; /* bitmask of Qcow2MetadataOverlap values */
 313     bool signaled_corruption;
 314
 315     uint64_t incompatible_features;
 316     uint64_t compatible_features;
 317     uint64_t autoclear_features;
 318
 319     size_t unknown_header_fields_size;
 320     void* unknown_header_fields;
 321     QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
 322     QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
 323     bool cache_discards;
 324
 325     /* Backing file path and format as stored in the image (this is not the
 326      * effective path/format, which may be the result of a runtime option
 327      * override) */
 328     char *image_backing_file;
 329     char *image_backing_format;
 330
 331     CoQueue compress_wait_queue;
 332     int nb_compress_threads;
 333 } BDRVQcow2State;
 334
 335 typedef struct Qcow2COWRegion {
 336     /**
 337      * Offset of the COW region in bytes from the start of the first cluster
 338      * touched by the request.
 339      */
 340     unsigned    offset;
 341
 342     /** Number of bytes to copy */
 343     unsigned    nb_bytes;
 344 } Qcow2COWRegion;
 345
 346 /**
 347  * Describes an in-flight (part of a) write request that writes to clusters
 348  * that are not referenced in their L2 table yet.
 349  */
 350 typedef struct QCowL2Meta
 351 {
 352     /** Guest offset of the first newly allocated cluster */
 353     uint64_t offset;
 354
 355     /** Host offset of the first newly allocated cluster */
 356     uint64_t alloc_offset;
 357
 358     /** Number of newly allocated clusters */
 359     int nb_clusters;
 360
 361     /** Do not free the old clusters */
 362     bool keep_old_clusters;
 363
 364     /**
 365      * Requests that overlap with this allocation and wait to be restarted
 366      * when the allocating request has completed.
 367      */
 368     CoQueue dependent_requests;
 369
 370     /**
 371      * The COW Region between the start of the first allocated cluster and the
 372      * area the guest actually writes to.
 373      */
 374     Qcow2COWRegion cow_start;
 375
 376     /**
 377      * The COW Region between the area the guest actually writes to and the
 378      * end of the last allocated cluster.
 379      */
 380     Qcow2COWRegion cow_end;
 381
 382     /**
 383      * The I/O vector with the data from the actual guest write request.
 384      * If non-NULL, this is meant to be merged together with the data
 385      * from @cow_start and @cow_end into one single write operation.
 386      */
 387     QEMUIOVector *data_qiov;
 388
 389     /** Pointer to next L2Meta of the same write request */
 390     struct QCowL2Meta *next;
 391
 392     QLIST_ENTRY(QCowL2Meta) next_in_flight;
 393 } QCowL2Meta;
 394
 395 typedef enum QCow2ClusterType {
 396     QCOW2_CLUSTER_UNALLOCATED,
 397     QCOW2_CLUSTER_ZERO_PLAIN,
 398     QCOW2_CLUSTER_ZERO_ALLOC,
 399     QCOW2_CLUSTER_NORMAL,
 400     QCOW2_CLUSTER_COMPRESSED,
 401 } QCow2ClusterType;
 402
 403 typedef enum QCow2MetadataOverlap {
 404     QCOW2_OL_MAIN_HEADER_BITNR      = 0,
 405     QCOW2_OL_ACTIVE_L1_BITNR        = 1,
 406     QCOW2_OL_ACTIVE_L2_BITNR        = 2,
 407     QCOW2_OL_REFCOUNT_TABLE_BITNR   = 3,
 408     QCOW2_OL_REFCOUNT_BLOCK_BITNR   = 4,
 409     QCOW2_OL_SNAPSHOT_TABLE_BITNR   = 5,
 410     QCOW2_OL_INACTIVE_L1_BITNR      = 6,
 411     QCOW2_OL_INACTIVE_L2_BITNR      = 7,
 412     QCOW2_OL_BITMAP_DIRECTORY_BITNR = 8,
 413
 414     QCOW2_OL_MAX_BITNR              = 9,
 415
 416     QCOW2_OL_NONE             = 0,
 417     QCOW2_OL_MAIN_HEADER      = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
 418     QCOW2_OL_ACTIVE_L1        = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
 419     QCOW2_OL_ACTIVE_L2        = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
 420     QCOW2_OL_REFCOUNT_TABLE   = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
 421     QCOW2_OL_REFCOUNT_BLOCK   = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
 422     QCOW2_OL_SNAPSHOT_TABLE   = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
 423     QCOW2_OL_INACTIVE_L1      = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
 424     /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
 425      * reads. */
 426     QCOW2_OL_INACTIVE_L2      = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
 427     QCOW2_OL_BITMAP_DIRECTORY = (1 << QCOW2_OL_BITMAP_DIRECTORY_BITNR),
 428 } QCow2MetadataOverlap;
 429
 430 /* Perform all overlap checks which can be done in constant time */
 431 #define QCOW2_OL_CONSTANT \
 432     (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
 433      QCOW2_OL_SNAPSHOT_TABLE | QCOW2_OL_BITMAP_DIRECTORY)
 434
 435 /* Perform all overlap checks which don't require disk access */
 436 #define QCOW2_OL_CACHED \
 437     (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
 438      QCOW2_OL_INACTIVE_L1)
 439
 440 /* Perform all overlap checks */
 441 #define QCOW2_OL_ALL \
 442     (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
 443
 444 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
 445 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
 446 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
 447
 448 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
 449
 450 static inline int64_t start_of_cluster(BDRVQcow2State *s, int64_t offset)
 451 {
 452     return offset & ~(s->cluster_size - 1);
 453 }
 454
 455 static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset)
 456 {
 457     return offset & (s->cluster_size - 1);
 458 }
 459
 460 static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
 461 {
 462     return (size + (s->cluster_size - 1)) >> s->cluster_bits;
 463 }
 464
 465 static inline int64_t size_to_l1(BDRVQcow2State *s, int64_t size)
 466 {
 467     int shift = s->cluster_bits + s->l2_bits;
 468     return (size + (1ULL << shift) - 1) >> shift;
 469 }
 470
 471 static inline int offset_to_l1_index(BDRVQcow2State *s, uint64_t offset)
 472 {
 473     return offset >> (s->l2_bits + s->cluster_bits);
 474 }
 475
 476 static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset)
 477 {
 478     return (offset >> s->cluster_bits) & (s->l2_size - 1);
 479 }
 480
 481 static inline int offset_to_l2_slice_index(BDRVQcow2State *s, int64_t offset)
 482 {
 483     return (offset >> s->cluster_bits) & (s->l2_slice_size - 1);
 484 }
 485
 486 static inline int64_t qcow2_vm_state_offset(BDRVQcow2State *s)
 487 {
 488     return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
 489 }
 490
 491 static inline QCow2ClusterType qcow2_get_cluster_type(uint64_t l2_entry)
 492 {
 493     if (l2_entry & QCOW_OFLAG_COMPRESSED) {
 494         return QCOW2_CLUSTER_COMPRESSED;
 495     } else if (l2_entry & QCOW_OFLAG_ZERO) {
 496         if (l2_entry & L2E_OFFSET_MASK) {
 497             return QCOW2_CLUSTER_ZERO_ALLOC;
 498         }
 499         return QCOW2_CLUSTER_ZERO_PLAIN;
 500     } else if (!(l2_entry & L2E_OFFSET_MASK)) {
 501         return QCOW2_CLUSTER_UNALLOCATED;
 502     } else {
 503         return QCOW2_CLUSTER_NORMAL;
 504     }
 505 }
 506
 507 /* Check whether refcounts are eager or lazy */
 508 static inline bool qcow2_need_accurate_refcounts(BDRVQcow2State *s)
 509 {
 510     return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
 511 }
 512
 513 static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
 514 {
 515     return m->offset + m->cow_start.offset;
 516 }
 517
 518 static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
 519 {
 520     return m->offset + m->cow_end.offset + m->cow_end.nb_bytes;
 521 }
 522
 523 static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2)
 524 {
 525     return r1 > r2 ? r1 - r2 : r2 - r1;
 526 }
 527
 528 static inline
 529 uint32_t offset_to_reftable_index(BDRVQcow2State *s, uint64_t offset)
 530 {
 531     return offset >> (s->refcount_block_bits + s->cluster_bits);
 532 }
 533
 534 /* qcow2.c functions */
 535 int64_t qcow2_refcount_metadata_size(int64_t clusters, size_t cluster_size,
 536                                      int refcount_order, bool generous_increase,
 537                                      uint64_t *refblock_count);
 538
 539 int qcow2_mark_dirty(BlockDriverState *bs);
 540 int qcow2_mark_corrupt(BlockDriverState *bs);
 541 int qcow2_mark_consistent(BlockDriverState *bs);
 542 int qcow2_update_header(BlockDriverState *bs);
 543
 544 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
 545                              int64_t size, const char *message_format, ...)
 546                              GCC_FMT_ATTR(5, 6);
 547
 548 int qcow2_validate_table(BlockDriverState *bs, uint64_t offset,
 549                          uint64_t entries, size_t entry_len,
 550                          int64_t max_size_bytes, const char *table_name,
 551                          Error **errp);
 552
 553 /* qcow2-refcount.c functions */
 554 int qcow2_refcount_init(BlockDriverState *bs);
 555 void qcow2_refcount_close(BlockDriverState *bs);
 556
 557 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index,
 558                        uint64_t *refcount);
 559
 560 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
 561                                   uint64_t addend, bool decrease,
 562                                   enum qcow2_discard_type type);
 563
 564 int64_t qcow2_refcount_area(BlockDriverState *bs, uint64_t offset,
 565                             uint64_t additional_clusters, bool exact_size,
 566                             int new_refblock_index,
 567                             uint64_t new_refblock_offset);
 568
 569 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
 570 int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
 571                                 int64_t nb_clusters);
 572 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
 573 void qcow2_free_clusters(BlockDriverState *bs,
 574                           int64_t offset, int64_t size,
 575                           enum qcow2_discard_type type);
 576 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
 577                              int nb_clusters, enum qcow2_discard_type type);
 578
 579 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
 580     int64_t l1_table_offset, int l1_size, int addend);
 581
 582 int coroutine_fn qcow2_flush_caches(BlockDriverState *bs);
 583 int coroutine_fn qcow2_write_caches(BlockDriverState *bs);
 584 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 585                           BdrvCheckMode fix);
 586
 587 void qcow2_process_discards(BlockDriverState *bs, int ret);
 588
 589 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
 590                                  int64_t size);
 591 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
 592                                   int64_t size);
 593 int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
 594                              void **refcount_table,
 595                              int64_t *refcount_table_size,
 596                              int64_t offset, int64_t size);
 597
 598 int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
 599                                 BlockDriverAmendStatusCB *status_cb,
 600                                 void *cb_opaque, Error **errp);
 601 int qcow2_shrink_reftable(BlockDriverState *bs);
 602 int64_t qcow2_get_last_cluster(BlockDriverState *bs, int64_t size);
 603
 604 /* qcow2-cluster.c functions */
 605 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
 606                         bool exact_size);
 607 int qcow2_shrink_l1_table(BlockDriverState *bs, uint64_t max_size);
 608 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
 609 int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
 610 int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num,
 611                           uint8_t *buf, int nb_sectors, bool enc, Error **errp);
 612
 613 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
 614                              unsigned int *bytes, uint64_t *cluster_offset);
 615 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
 616                                unsigned int *bytes, uint64_t *host_offset,
 617                                QCowL2Meta **m);
 618 uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
 619                                          uint64_t offset,
 620                                          int compressed_size);
 621
 622 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
 623 void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m);
 624 int qcow2_cluster_discard(BlockDriverState *bs, uint64_t offset,
 625                           uint64_t bytes, enum qcow2_discard_type type,
 626                           bool full_discard);
 627 int qcow2_cluster_zeroize(BlockDriverState *bs, uint64_t offset,
 628                           uint64_t bytes, int flags);
 629
 630 int qcow2_expand_zero_clusters(BlockDriverState *bs,
 631                                BlockDriverAmendStatusCB *status_cb,
 632                                void *cb_opaque);
 633
 634 /* qcow2-snapshot.c functions */
 635 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
 636 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
 637 int qcow2_snapshot_delete(BlockDriverState *bs,
 638                           const char *snapshot_id,
 639                           const char *name,
 640                           Error **errp);
 641 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
 642 int qcow2_snapshot_load_tmp(BlockDriverState *bs,
 643                             const char *snapshot_id,
 644                             const char *name,
 645                             Error **errp);
 646
 647 void qcow2_free_snapshots(BlockDriverState *bs);
 648 int qcow2_read_snapshots(BlockDriverState *bs);
 649
 650 /* qcow2-cache.c functions */
 651 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
 652                                unsigned table_size);
 653 int qcow2_cache_destroy(Qcow2Cache *c);
 654
 655 void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
 656 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
 657 int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c);
 658 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
 659     Qcow2Cache *dependency);
 660 void qcow2_cache_depends_on_flush(Qcow2Cache *c);
 661
 662 void qcow2_cache_clean_unused(Qcow2Cache *c);
 663 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c);
 664
 665 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 666     void **table);
 667 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
 668     void **table);
 669 void qcow2_cache_put(Qcow2Cache *c, void **table);
 670 void *qcow2_cache_is_table_offset(Qcow2Cache *c, uint64_t offset);
 671 void qcow2_cache_discard(Qcow2Cache *c, void *table);
 672
 673 /* qcow2-bitmap.c functions */
 674 int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
 675                                   void **refcount_table,
 676                                   int64_t *refcount_table_size);
 677 bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp);
 678 int qcow2_reopen_bitmaps_rw_hint(BlockDriverState *bs, bool *header_updated,
 679                                  Error **errp);
 680 int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp);
 681 void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp);
 682 int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp);
 683 bool qcow2_can_store_new_dirty_bitmap(BlockDriverState *bs,
 684                                       const char *name,
 685                                       uint32_t granularity,
 686                                       Error **errp);
 687 void qcow2_remove_persistent_dirty_bitmap(BlockDriverState *bs,
 688                                           const char *name,
 689                                           Error **errp);
 690
 691 #endif