xen: Remove xen_cmos_set_s3_resume()
[qemu/qmp-unstable.git] / block / qcow2.h
blob6e39a1b639ec22c119b56bf6593ccc9fb57a53a4
1 /*
2 * Block driver for the QCOW version 2 format
4 * Copyright (c) 2004-2006 Fabrice Bellard
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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.
25 #ifndef BLOCK_QCOW2_H
26 #define BLOCK_QCOW2_H
28 #include "qemu/aes.h"
29 #include "block/coroutine.h"
31 //#define DEBUG_ALLOC
32 //#define DEBUG_ALLOC2
33 //#define DEBUG_EXT
35 #define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
37 #define QCOW_CRYPT_NONE 0
38 #define QCOW_CRYPT_AES 1
40 #define QCOW_MAX_CRYPT_CLUSTERS 32
41 #define QCOW_MAX_SNAPSHOTS 65536
43 /* 8 MB refcount table is enough for 2 PB images at 64k cluster size
44 * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */
45 #define QCOW_MAX_REFTABLE_SIZE 0x800000
47 /* 32 MB L1 table is enough for 2 PB images at 64k cluster size
48 * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */
49 #define QCOW_MAX_L1_SIZE 0x2000000
51 /* Allow for an average of 1k per snapshot table entry, should be plenty of
52 * space for snapshot names and IDs */
53 #define QCOW_MAX_SNAPSHOTS_SIZE (1024 * QCOW_MAX_SNAPSHOTS)
55 /* indicate that the refcount of the referenced cluster is exactly one. */
56 #define QCOW_OFLAG_COPIED (1ULL << 63)
57 /* indicate that the cluster is compressed (they never have the copied flag) */
58 #define QCOW_OFLAG_COMPRESSED (1ULL << 62)
59 /* The cluster reads as all zeros */
60 #define QCOW_OFLAG_ZERO (1ULL << 0)
62 #define MIN_CLUSTER_BITS 9
63 #define MAX_CLUSTER_BITS 21
65 #define MIN_L2_CACHE_SIZE 1 /* cluster */
67 /* Must be at least 4 to cover all cases of refcount table growth */
68 #define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */
70 #define DEFAULT_L2_CACHE_BYTE_SIZE 1048576 /* bytes */
72 /* The refblock cache needs only a fourth of the L2 cache size to cover as many
73 * clusters */
74 #define DEFAULT_L2_REFCOUNT_SIZE_RATIO 4
76 #define DEFAULT_CLUSTER_SIZE 65536
79 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts"
80 #define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request"
81 #define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot"
82 #define QCOW2_OPT_DISCARD_OTHER "pass-discard-other"
83 #define QCOW2_OPT_OVERLAP "overlap-check"
84 #define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template"
85 #define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header"
86 #define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1"
87 #define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2"
88 #define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table"
89 #define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block"
90 #define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table"
91 #define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1"
92 #define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2"
93 #define QCOW2_OPT_CACHE_SIZE "cache-size"
94 #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size"
95 #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size"
97 typedef struct QCowHeader {
98 uint32_t magic;
99 uint32_t version;
100 uint64_t backing_file_offset;
101 uint32_t backing_file_size;
102 uint32_t cluster_bits;
103 uint64_t size; /* in bytes */
104 uint32_t crypt_method;
105 uint32_t l1_size; /* XXX: save number of clusters instead ? */
106 uint64_t l1_table_offset;
107 uint64_t refcount_table_offset;
108 uint32_t refcount_table_clusters;
109 uint32_t nb_snapshots;
110 uint64_t snapshots_offset;
112 /* The following fields are only valid for version >= 3 */
113 uint64_t incompatible_features;
114 uint64_t compatible_features;
115 uint64_t autoclear_features;
117 uint32_t refcount_order;
118 uint32_t header_length;
119 } QEMU_PACKED QCowHeader;
121 typedef struct QEMU_PACKED QCowSnapshotHeader {
122 /* header is 8 byte aligned */
123 uint64_t l1_table_offset;
125 uint32_t l1_size;
126 uint16_t id_str_size;
127 uint16_t name_size;
129 uint32_t date_sec;
130 uint32_t date_nsec;
132 uint64_t vm_clock_nsec;
134 uint32_t vm_state_size;
135 uint32_t extra_data_size; /* for extension */
136 /* extra data follows */
137 /* id_str follows */
138 /* name follows */
139 } QCowSnapshotHeader;
141 typedef struct QEMU_PACKED QCowSnapshotExtraData {
142 uint64_t vm_state_size_large;
143 uint64_t disk_size;
144 } QCowSnapshotExtraData;
147 typedef struct QCowSnapshot {
148 uint64_t l1_table_offset;
149 uint32_t l1_size;
150 char *id_str;
151 char *name;
152 uint64_t disk_size;
153 uint64_t vm_state_size;
154 uint32_t date_sec;
155 uint32_t date_nsec;
156 uint64_t vm_clock_nsec;
157 } QCowSnapshot;
159 struct Qcow2Cache;
160 typedef struct Qcow2Cache Qcow2Cache;
162 typedef struct Qcow2UnknownHeaderExtension {
163 uint32_t magic;
164 uint32_t len;
165 QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
166 uint8_t data[];
167 } Qcow2UnknownHeaderExtension;
169 enum {
170 QCOW2_FEAT_TYPE_INCOMPATIBLE = 0,
171 QCOW2_FEAT_TYPE_COMPATIBLE = 1,
172 QCOW2_FEAT_TYPE_AUTOCLEAR = 2,
175 /* Incompatible feature bits */
176 enum {
177 QCOW2_INCOMPAT_DIRTY_BITNR = 0,
178 QCOW2_INCOMPAT_CORRUPT_BITNR = 1,
179 QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
180 QCOW2_INCOMPAT_CORRUPT = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
182 QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY
183 | QCOW2_INCOMPAT_CORRUPT,
186 /* Compatible feature bits */
187 enum {
188 QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
189 QCOW2_COMPAT_LAZY_REFCOUNTS = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
191 QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS,
194 enum qcow2_discard_type {
195 QCOW2_DISCARD_NEVER = 0,
196 QCOW2_DISCARD_ALWAYS,
197 QCOW2_DISCARD_REQUEST,
198 QCOW2_DISCARD_SNAPSHOT,
199 QCOW2_DISCARD_OTHER,
200 QCOW2_DISCARD_MAX
203 typedef struct Qcow2Feature {
204 uint8_t type;
205 uint8_t bit;
206 char name[46];
207 } QEMU_PACKED Qcow2Feature;
209 typedef struct Qcow2DiscardRegion {
210 BlockDriverState *bs;
211 uint64_t offset;
212 uint64_t bytes;
213 QTAILQ_ENTRY(Qcow2DiscardRegion) next;
214 } Qcow2DiscardRegion;
216 typedef struct BDRVQcowState {
217 int cluster_bits;
218 int cluster_size;
219 int cluster_sectors;
220 int l2_bits;
221 int l2_size;
222 int l1_size;
223 int l1_vm_state_index;
224 int refcount_block_bits;
225 int refcount_block_size;
226 int csize_shift;
227 int csize_mask;
228 uint64_t cluster_offset_mask;
229 uint64_t l1_table_offset;
230 uint64_t *l1_table;
232 Qcow2Cache* l2_table_cache;
233 Qcow2Cache* refcount_block_cache;
235 uint8_t *cluster_cache;
236 uint8_t *cluster_data;
237 uint64_t cluster_cache_offset;
238 QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
240 uint64_t *refcount_table;
241 uint64_t refcount_table_offset;
242 uint32_t refcount_table_size;
243 uint64_t free_cluster_index;
244 uint64_t free_byte_offset;
246 CoMutex lock;
248 uint32_t crypt_method; /* current crypt method, 0 if no key yet */
249 uint32_t crypt_method_header;
250 AES_KEY aes_encrypt_key;
251 AES_KEY aes_decrypt_key;
252 uint64_t snapshots_offset;
253 int snapshots_size;
254 unsigned int nb_snapshots;
255 QCowSnapshot *snapshots;
257 int flags;
258 int qcow_version;
259 bool use_lazy_refcounts;
260 int refcount_order;
262 bool discard_passthrough[QCOW2_DISCARD_MAX];
264 int overlap_check; /* bitmask of Qcow2MetadataOverlap values */
265 bool signaled_corruption;
267 uint64_t incompatible_features;
268 uint64_t compatible_features;
269 uint64_t autoclear_features;
271 size_t unknown_header_fields_size;
272 void* unknown_header_fields;
273 QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
274 QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
275 bool cache_discards;
276 } BDRVQcowState;
278 /* XXX: use std qcow open function ? */
279 typedef struct QCowCreateState {
280 int cluster_size;
281 int cluster_bits;
282 uint16_t *refcount_block;
283 uint64_t *refcount_table;
284 int64_t l1_table_offset;
285 int64_t refcount_table_offset;
286 int64_t refcount_block_offset;
287 } QCowCreateState;
289 struct QCowAIOCB;
291 typedef struct Qcow2COWRegion {
293 * Offset of the COW region in bytes from the start of the first cluster
294 * touched by the request.
296 uint64_t offset;
298 /** Number of sectors to copy */
299 int nb_sectors;
300 } Qcow2COWRegion;
303 * Describes an in-flight (part of a) write request that writes to clusters
304 * that are not referenced in their L2 table yet.
306 typedef struct QCowL2Meta
308 /** Guest offset of the first newly allocated cluster */
309 uint64_t offset;
311 /** Host offset of the first newly allocated cluster */
312 uint64_t alloc_offset;
315 * Number of sectors from the start of the first allocated cluster to
316 * the end of the (possibly shortened) request
318 int nb_available;
320 /** Number of newly allocated clusters */
321 int nb_clusters;
324 * Requests that overlap with this allocation and wait to be restarted
325 * when the allocating request has completed.
327 CoQueue dependent_requests;
330 * The COW Region between the start of the first allocated cluster and the
331 * area the guest actually writes to.
333 Qcow2COWRegion cow_start;
336 * The COW Region between the area the guest actually writes to and the
337 * end of the last allocated cluster.
339 Qcow2COWRegion cow_end;
341 /** Pointer to next L2Meta of the same write request */
342 struct QCowL2Meta *next;
344 QLIST_ENTRY(QCowL2Meta) next_in_flight;
345 } QCowL2Meta;
347 enum {
348 QCOW2_CLUSTER_UNALLOCATED,
349 QCOW2_CLUSTER_NORMAL,
350 QCOW2_CLUSTER_COMPRESSED,
351 QCOW2_CLUSTER_ZERO
354 typedef enum QCow2MetadataOverlap {
355 QCOW2_OL_MAIN_HEADER_BITNR = 0,
356 QCOW2_OL_ACTIVE_L1_BITNR = 1,
357 QCOW2_OL_ACTIVE_L2_BITNR = 2,
358 QCOW2_OL_REFCOUNT_TABLE_BITNR = 3,
359 QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4,
360 QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5,
361 QCOW2_OL_INACTIVE_L1_BITNR = 6,
362 QCOW2_OL_INACTIVE_L2_BITNR = 7,
364 QCOW2_OL_MAX_BITNR = 8,
366 QCOW2_OL_NONE = 0,
367 QCOW2_OL_MAIN_HEADER = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
368 QCOW2_OL_ACTIVE_L1 = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
369 QCOW2_OL_ACTIVE_L2 = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
370 QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
371 QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
372 QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
373 QCOW2_OL_INACTIVE_L1 = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
374 /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
375 * reads. */
376 QCOW2_OL_INACTIVE_L2 = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
377 } QCow2MetadataOverlap;
379 /* Perform all overlap checks which can be done in constant time */
380 #define QCOW2_OL_CONSTANT \
381 (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
382 QCOW2_OL_SNAPSHOT_TABLE)
384 /* Perform all overlap checks which don't require disk access */
385 #define QCOW2_OL_CACHED \
386 (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
387 QCOW2_OL_INACTIVE_L1)
389 /* Perform all overlap checks */
390 #define QCOW2_OL_ALL \
391 (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
393 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
394 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
395 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
397 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
399 static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset)
401 return offset & ~(s->cluster_size - 1);
404 static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset)
406 return offset & (s->cluster_size - 1);
409 static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
411 return (size + (s->cluster_size - 1)) >> s->cluster_bits;
414 static inline int64_t size_to_l1(BDRVQcowState *s, int64_t size)
416 int shift = s->cluster_bits + s->l2_bits;
417 return (size + (1ULL << shift) - 1) >> shift;
420 static inline int offset_to_l2_index(BDRVQcowState *s, int64_t offset)
422 return (offset >> s->cluster_bits) & (s->l2_size - 1);
425 static inline int64_t align_offset(int64_t offset, int n)
427 offset = (offset + n - 1) & ~(n - 1);
428 return offset;
431 static inline int64_t qcow2_vm_state_offset(BDRVQcowState *s)
433 return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
436 static inline uint64_t qcow2_max_refcount_clusters(BDRVQcowState *s)
438 return QCOW_MAX_REFTABLE_SIZE >> s->cluster_bits;
441 static inline int qcow2_get_cluster_type(uint64_t l2_entry)
443 if (l2_entry & QCOW_OFLAG_COMPRESSED) {
444 return QCOW2_CLUSTER_COMPRESSED;
445 } else if (l2_entry & QCOW_OFLAG_ZERO) {
446 return QCOW2_CLUSTER_ZERO;
447 } else if (!(l2_entry & L2E_OFFSET_MASK)) {
448 return QCOW2_CLUSTER_UNALLOCATED;
449 } else {
450 return QCOW2_CLUSTER_NORMAL;
454 /* Check whether refcounts are eager or lazy */
455 static inline bool qcow2_need_accurate_refcounts(BDRVQcowState *s)
457 return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
460 static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
462 return m->offset + m->cow_start.offset;
465 static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
467 return m->offset + m->cow_end.offset
468 + (m->cow_end.nb_sectors << BDRV_SECTOR_BITS);
471 // FIXME Need qcow2_ prefix to global functions
473 /* qcow2.c functions */
474 int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
475 int64_t sector_num, int nb_sectors);
477 int qcow2_mark_dirty(BlockDriverState *bs);
478 int qcow2_mark_corrupt(BlockDriverState *bs);
479 int qcow2_mark_consistent(BlockDriverState *bs);
480 int qcow2_update_header(BlockDriverState *bs);
482 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
483 int64_t size, const char *message_format, ...)
484 GCC_FMT_ATTR(5, 6);
486 /* qcow2-refcount.c functions */
487 int qcow2_refcount_init(BlockDriverState *bs);
488 void qcow2_refcount_close(BlockDriverState *bs);
490 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index);
492 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
493 int addend, enum qcow2_discard_type type);
495 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
496 int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
497 int nb_clusters);
498 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
499 void qcow2_free_clusters(BlockDriverState *bs,
500 int64_t offset, int64_t size,
501 enum qcow2_discard_type type);
502 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
503 int nb_clusters, enum qcow2_discard_type type);
505 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
506 int64_t l1_table_offset, int l1_size, int addend);
508 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
509 BdrvCheckMode fix);
511 void qcow2_process_discards(BlockDriverState *bs, int ret);
513 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
514 int64_t size);
515 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
516 int64_t size);
518 /* qcow2-cluster.c functions */
519 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
520 bool exact_size);
521 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
522 void qcow2_l2_cache_reset(BlockDriverState *bs);
523 int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
524 void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
525 uint8_t *out_buf, const uint8_t *in_buf,
526 int nb_sectors, int enc,
527 const AES_KEY *key);
529 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
530 int *num, uint64_t *cluster_offset);
531 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
532 int *num, uint64_t *host_offset, QCowL2Meta **m);
533 uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
534 uint64_t offset,
535 int compressed_size);
537 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
538 int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
539 int nb_sectors, enum qcow2_discard_type type, bool full_discard);
540 int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors);
542 int qcow2_expand_zero_clusters(BlockDriverState *bs,
543 BlockDriverAmendStatusCB *status_cb);
545 /* qcow2-snapshot.c functions */
546 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
547 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
548 int qcow2_snapshot_delete(BlockDriverState *bs,
549 const char *snapshot_id,
550 const char *name,
551 Error **errp);
552 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
553 int qcow2_snapshot_load_tmp(BlockDriverState *bs,
554 const char *snapshot_id,
555 const char *name,
556 Error **errp);
558 void qcow2_free_snapshots(BlockDriverState *bs);
559 int qcow2_read_snapshots(BlockDriverState *bs);
561 /* qcow2-cache.c functions */
562 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables);
563 int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
565 void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
566 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
567 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
568 Qcow2Cache *dependency);
569 void qcow2_cache_depends_on_flush(Qcow2Cache *c);
571 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c);
573 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
574 void **table);
575 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
576 void **table);
577 int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
579 #endif