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25#ifndef BLOCK_QCOW2_H
26#define BLOCK_QCOW2_H
27
28#include "crypto/cipher.h"
29#include "qemu/coroutine.h"
30
31
32
33
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
40#define QCOW_MAX_CRYPT_CLUSTERS 32
41#define QCOW_MAX_SNAPSHOTS 65536
42
43
44
45#define QCOW_MAX_REFTABLE_SIZE 0x800000
46
47
48
49#define QCOW_MAX_L1_SIZE 0x2000000
50
51
52
53#define QCOW_MAX_SNAPSHOTS_SIZE (1024 * QCOW_MAX_SNAPSHOTS)
54
55
56#define QCOW_OFLAG_COPIED (1ULL << 63)
57
58#define QCOW_OFLAG_COMPRESSED (1ULL << 62)
59
60#define QCOW_OFLAG_ZERO (1ULL << 0)
61
62#define MIN_CLUSTER_BITS 9
63#define MAX_CLUSTER_BITS 21
64
65
66#define MIN_L2_CACHE_SIZE 2
67
68
69#define MIN_REFCOUNT_CACHE_SIZE 4
70
71
72#define DEFAULT_L2_CACHE_CLUSTERS 8
73#define DEFAULT_L2_CACHE_BYTE_SIZE 1048576
74
75
76
77#define DEFAULT_L2_REFCOUNT_SIZE_RATIO 4
78
79#define DEFAULT_CLUSTER_SIZE 65536
80
81
82#define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts"
83#define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request"
84#define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot"
85#define QCOW2_OPT_DISCARD_OTHER "pass-discard-other"
86#define QCOW2_OPT_OVERLAP "overlap-check"
87#define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template"
88#define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header"
89#define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1"
90#define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2"
91#define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table"
92#define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block"
93#define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table"
94#define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1"
95#define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2"
96#define QCOW2_OPT_CACHE_SIZE "cache-size"
97#define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size"
98#define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size"
99#define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval"
100
101typedef struct QCowHeader {
102 uint32_t magic;
103 uint32_t version;
104 uint64_t backing_file_offset;
105 uint32_t backing_file_size;
106 uint32_t cluster_bits;
107 uint64_t size;
108 uint32_t crypt_method;
109 uint32_t l1_size;
110 uint64_t l1_table_offset;
111 uint64_t refcount_table_offset;
112 uint32_t refcount_table_clusters;
113 uint32_t nb_snapshots;
114 uint64_t snapshots_offset;
115
116
117 uint64_t incompatible_features;
118 uint64_t compatible_features;
119 uint64_t autoclear_features;
120
121 uint32_t refcount_order;
122 uint32_t header_length;
123} QEMU_PACKED QCowHeader;
124
125typedef struct QEMU_PACKED QCowSnapshotHeader {
126
127 uint64_t l1_table_offset;
128
129 uint32_t l1_size;
130 uint16_t id_str_size;
131 uint16_t name_size;
132
133 uint32_t date_sec;
134 uint32_t date_nsec;
135
136 uint64_t vm_clock_nsec;
137
138 uint32_t vm_state_size;
139 uint32_t extra_data_size;
140
141
142
143} QCowSnapshotHeader;
144
145typedef struct QEMU_PACKED QCowSnapshotExtraData {
146 uint64_t vm_state_size_large;
147 uint64_t disk_size;
148} QCowSnapshotExtraData;
149
150
151typedef struct QCowSnapshot {
152 uint64_t l1_table_offset;
153 uint32_t l1_size;
154 char *id_str;
155 char *name;
156 uint64_t disk_size;
157 uint64_t vm_state_size;
158 uint32_t date_sec;
159 uint32_t date_nsec;
160 uint64_t vm_clock_nsec;
161} QCowSnapshot;
162
163struct Qcow2Cache;
164typedef struct Qcow2Cache Qcow2Cache;
165
166typedef struct Qcow2UnknownHeaderExtension {
167 uint32_t magic;
168 uint32_t len;
169 QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
170 uint8_t data[];
171} Qcow2UnknownHeaderExtension;
172
173enum {
174 QCOW2_FEAT_TYPE_INCOMPATIBLE = 0,
175 QCOW2_FEAT_TYPE_COMPATIBLE = 1,
176 QCOW2_FEAT_TYPE_AUTOCLEAR = 2,
177};
178
179
180enum {
181 QCOW2_INCOMPAT_DIRTY_BITNR = 0,
182 QCOW2_INCOMPAT_CORRUPT_BITNR = 1,
183 QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
184 QCOW2_INCOMPAT_CORRUPT = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
185
186 QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY
187 | QCOW2_INCOMPAT_CORRUPT,
188};
189
190
191enum {
192 QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
193 QCOW2_COMPAT_LAZY_REFCOUNTS = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
194
195 QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS,
196};
197
198enum qcow2_discard_type {
199 QCOW2_DISCARD_NEVER = 0,
200 QCOW2_DISCARD_ALWAYS,
201 QCOW2_DISCARD_REQUEST,
202 QCOW2_DISCARD_SNAPSHOT,
203 QCOW2_DISCARD_OTHER,
204 QCOW2_DISCARD_MAX
205};
206
207typedef struct Qcow2Feature {
208 uint8_t type;
209 uint8_t bit;
210 char name[46];
211} QEMU_PACKED Qcow2Feature;
212
213typedef struct Qcow2DiscardRegion {
214 BlockDriverState *bs;
215 uint64_t offset;
216 uint64_t bytes;
217 QTAILQ_ENTRY(Qcow2DiscardRegion) next;
218} Qcow2DiscardRegion;
219
220typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
221 uint64_t index);
222typedef void Qcow2SetRefcountFunc(void *refcount_array,
223 uint64_t index, uint64_t value);
224
225typedef struct BDRVQcow2State {
226 int cluster_bits;
227 int cluster_size;
228 int cluster_sectors;
229 int l2_bits;
230 int l2_size;
231 int l1_size;
232 int l1_vm_state_index;
233 int refcount_block_bits;
234 int refcount_block_size;
235 int csize_shift;
236 int csize_mask;
237 uint64_t cluster_offset_mask;
238 uint64_t l1_table_offset;
239 uint64_t *l1_table;
240
241 Qcow2Cache* l2_table_cache;
242 Qcow2Cache* refcount_block_cache;
243 QEMUTimer *cache_clean_timer;
244 unsigned cache_clean_interval;
245
246 uint8_t *cluster_cache;
247 uint8_t *cluster_data;
248 uint64_t cluster_cache_offset;
249 QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
250
251 uint64_t *refcount_table;
252 uint64_t refcount_table_offset;
253 uint32_t refcount_table_size;
254 uint64_t free_cluster_index;
255 uint64_t free_byte_offset;
256
257 CoMutex lock;
258
259 QCryptoCipher *cipher;
260 uint32_t crypt_method_header;
261 uint64_t snapshots_offset;
262 int snapshots_size;
263 unsigned int nb_snapshots;
264 QCowSnapshot *snapshots;
265
266 int flags;
267 int qcow_version;
268 bool use_lazy_refcounts;
269 int refcount_order;
270 int refcount_bits;
271 uint64_t refcount_max;
272
273 Qcow2GetRefcountFunc *get_refcount;
274 Qcow2SetRefcountFunc *set_refcount;
275
276 bool discard_passthrough[QCOW2_DISCARD_MAX];
277
278 int overlap_check;
279 bool signaled_corruption;
280
281 uint64_t incompatible_features;
282 uint64_t compatible_features;
283 uint64_t autoclear_features;
284
285 size_t unknown_header_fields_size;
286 void* unknown_header_fields;
287 QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
288 QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
289 bool cache_discards;
290
291
292
293
294 char *image_backing_file;
295 char *image_backing_format;
296} BDRVQcow2State;
297
298typedef struct Qcow2COWRegion {
299
300
301
302
303 uint64_t offset;
304
305
306 int nb_bytes;
307} Qcow2COWRegion;
308
309
310
311
312
313typedef struct QCowL2Meta
314{
315
316 uint64_t offset;
317
318
319 uint64_t alloc_offset;
320
321
322 int nb_clusters;
323
324
325
326
327
328 CoQueue dependent_requests;
329
330
331
332
333
334 Qcow2COWRegion cow_start;
335
336
337
338
339
340 Qcow2COWRegion cow_end;
341
342
343 struct QCowL2Meta *next;
344
345 QLIST_ENTRY(QCowL2Meta) next_in_flight;
346} QCowL2Meta;
347
348enum {
349 QCOW2_CLUSTER_UNALLOCATED,
350 QCOW2_CLUSTER_NORMAL,
351 QCOW2_CLUSTER_COMPRESSED,
352 QCOW2_CLUSTER_ZERO
353};
354
355typedef enum QCow2MetadataOverlap {
356 QCOW2_OL_MAIN_HEADER_BITNR = 0,
357 QCOW2_OL_ACTIVE_L1_BITNR = 1,
358 QCOW2_OL_ACTIVE_L2_BITNR = 2,
359 QCOW2_OL_REFCOUNT_TABLE_BITNR = 3,
360 QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4,
361 QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5,
362 QCOW2_OL_INACTIVE_L1_BITNR = 6,
363 QCOW2_OL_INACTIVE_L2_BITNR = 7,
364
365 QCOW2_OL_MAX_BITNR = 8,
366
367 QCOW2_OL_NONE = 0,
368 QCOW2_OL_MAIN_HEADER = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
369 QCOW2_OL_ACTIVE_L1 = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
370 QCOW2_OL_ACTIVE_L2 = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
371 QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
372 QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
373 QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
374 QCOW2_OL_INACTIVE_L1 = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
375
376
377 QCOW2_OL_INACTIVE_L2 = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
378} QCow2MetadataOverlap;
379
380
381#define QCOW2_OL_CONSTANT \
382 (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
383 QCOW2_OL_SNAPSHOT_TABLE)
384
385
386#define QCOW2_OL_CACHED \
387 (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
388 QCOW2_OL_INACTIVE_L1)
389
390
391#define QCOW2_OL_ALL \
392 (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
393
394#define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
395#define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
396#define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
397
398#define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
399
400static inline int64_t start_of_cluster(BDRVQcow2State *s, int64_t offset)
401{
402 return offset & ~(s->cluster_size - 1);
403}
404
405static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset)
406{
407 return offset & (s->cluster_size - 1);
408}
409
410static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
411{
412 return (size + (s->cluster_size - 1)) >> s->cluster_bits;
413}
414
415static inline int64_t size_to_l1(BDRVQcow2State *s, int64_t size)
416{
417 int shift = s->cluster_bits + s->l2_bits;
418 return (size + (1ULL << shift) - 1) >> shift;
419}
420
421static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset)
422{
423 return (offset >> s->cluster_bits) & (s->l2_size - 1);
424}
425
426static inline int64_t align_offset(int64_t offset, int n)
427{
428 offset = (offset + n - 1) & ~(n - 1);
429 return offset;
430}
431
432static inline int64_t qcow2_vm_state_offset(BDRVQcow2State *s)
433{
434 return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
435}
436
437static inline uint64_t qcow2_max_refcount_clusters(BDRVQcow2State *s)
438{
439 return QCOW_MAX_REFTABLE_SIZE >> s->cluster_bits;
440}
441
442static inline int qcow2_get_cluster_type(uint64_t l2_entry)
443{
444 if (l2_entry & QCOW_OFLAG_COMPRESSED) {
445 return QCOW2_CLUSTER_COMPRESSED;
446 } else if (l2_entry & QCOW_OFLAG_ZERO) {
447 return QCOW2_CLUSTER_ZERO;
448 } else if (!(l2_entry & L2E_OFFSET_MASK)) {
449 return QCOW2_CLUSTER_UNALLOCATED;
450 } else {
451 return QCOW2_CLUSTER_NORMAL;
452 }
453}
454
455
456static inline bool qcow2_need_accurate_refcounts(BDRVQcow2State *s)
457{
458 return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
459}
460
461static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
462{
463 return m->offset + m->cow_start.offset;
464}
465
466static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
467{
468 return m->offset + m->cow_end.offset + m->cow_end.nb_bytes;
469}
470
471static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2)
472{
473 return r1 > r2 ? r1 - r2 : r2 - r1;
474}
475
476
477int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
478 int64_t sector_num, int nb_sectors);
479
480int qcow2_mark_dirty(BlockDriverState *bs);
481int qcow2_mark_corrupt(BlockDriverState *bs);
482int qcow2_mark_consistent(BlockDriverState *bs);
483int qcow2_update_header(BlockDriverState *bs);
484
485void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
486 int64_t size, const char *message_format, ...)
487 GCC_FMT_ATTR(5, 6);
488
489
490int qcow2_refcount_init(BlockDriverState *bs);
491void qcow2_refcount_close(BlockDriverState *bs);
492
493int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index,
494 uint64_t *refcount);
495
496int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
497 uint64_t addend, bool decrease,
498 enum qcow2_discard_type type);
499
500int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
501int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
502 int64_t nb_clusters);
503int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
504void qcow2_free_clusters(BlockDriverState *bs,
505 int64_t offset, int64_t size,
506 enum qcow2_discard_type type);
507void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
508 int nb_clusters, enum qcow2_discard_type type);
509
510int qcow2_update_snapshot_refcount(BlockDriverState *bs,
511 int64_t l1_table_offset, int l1_size, int addend);
512
513int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
514 BdrvCheckMode fix);
515
516void qcow2_process_discards(BlockDriverState *bs, int ret);
517
518int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
519 int64_t size);
520int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
521 int64_t size);
522
523int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
524 BlockDriverAmendStatusCB *status_cb,
525 void *cb_opaque, Error **errp);
526
527
528int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
529 bool exact_size);
530int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
531int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
532int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num,
533 uint8_t *out_buf, const uint8_t *in_buf,
534 int nb_sectors, bool enc, Error **errp);
535
536int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
537 unsigned int *bytes, uint64_t *cluster_offset);
538int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
539 unsigned int *bytes, uint64_t *host_offset,
540 QCowL2Meta **m);
541uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
542 uint64_t offset,
543 int compressed_size);
544
545int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
546int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
547 int nb_sectors, enum qcow2_discard_type type, bool full_discard);
548int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors,
549 int flags);
550
551int qcow2_expand_zero_clusters(BlockDriverState *bs,
552 BlockDriverAmendStatusCB *status_cb,
553 void *cb_opaque);
554
555
556int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
557int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
558int qcow2_snapshot_delete(BlockDriverState *bs,
559 const char *snapshot_id,
560 const char *name,
561 Error **errp);
562int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
563int qcow2_snapshot_load_tmp(BlockDriverState *bs,
564 const char *snapshot_id,
565 const char *name,
566 Error **errp);
567
568void qcow2_free_snapshots(BlockDriverState *bs);
569int qcow2_read_snapshots(BlockDriverState *bs);
570
571
572Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables);
573int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
574
575void qcow2_cache_entry_mark_dirty(BlockDriverState *bs, Qcow2Cache *c,
576 void *table);
577int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
578int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c);
579int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
580 Qcow2Cache *dependency);
581void qcow2_cache_depends_on_flush(Qcow2Cache *c);
582
583void qcow2_cache_clean_unused(BlockDriverState *bs, Qcow2Cache *c);
584int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c);
585
586int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
587 void **table);
588int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
589 void **table);
590void qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
591
592#endif
593