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 MIN_CLUSTER_BITS 9
82 #define MAX_CLUSTER_BITS 21
83
84 /* Defined in the qcow2 spec (compressed cluster descriptor) */
85 #define QCOW2_COMPRESSED_SECTOR_SIZE 512U
86 #define QCOW2_COMPRESSED_SECTOR_MASK (~(QCOW2_COMPRESSED_SECTOR_SIZE - 1ULL))
87
88 /* Must be at least 2 to cover COW */
89 #define MIN_L2_CACHE_SIZE 2 /* cache entries */
90
91 /* Must be at least 4 to cover all cases of refcount table growth */
92 #define MIN_REFCOUNT_CACHE_SIZE 4 /* clusters */
93
94 #ifdef CONFIG_LINUX
95 #define DEFAULT_L2_CACHE_MAX_SIZE (32 * MiB)
96 #define DEFAULT_CACHE_CLEAN_INTERVAL 600 /* seconds */
97 #else
98 #define DEFAULT_L2_CACHE_MAX_SIZE (8 * MiB)
99 /* Cache clean interval is currently available only on Linux, so must be 0 */
100 #define DEFAULT_CACHE_CLEAN_INTERVAL 0
101 #endif
102
103 #define DEFAULT_CLUSTER_SIZE 65536
104
105 #define QCOW2_OPT_DATA_FILE "data-file"
106 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy-refcounts"
107 #define QCOW2_OPT_DISCARD_REQUEST "pass-discard-request"
108 #define QCOW2_OPT_DISCARD_SNAPSHOT "pass-discard-snapshot"
109 #define QCOW2_OPT_DISCARD_OTHER "pass-discard-other"
110 #define QCOW2_OPT_OVERLAP "overlap-check"
111 #define QCOW2_OPT_OVERLAP_TEMPLATE "overlap-check.template"
112 #define QCOW2_OPT_OVERLAP_MAIN_HEADER "overlap-check.main-header"
113 #define QCOW2_OPT_OVERLAP_ACTIVE_L1 "overlap-check.active-l1"
114 #define QCOW2_OPT_OVERLAP_ACTIVE_L2 "overlap-check.active-l2"
115 #define QCOW2_OPT_OVERLAP_REFCOUNT_TABLE "overlap-check.refcount-table"
116 #define QCOW2_OPT_OVERLAP_REFCOUNT_BLOCK "overlap-check.refcount-block"
117 #define QCOW2_OPT_OVERLAP_SNAPSHOT_TABLE "overlap-check.snapshot-table"
118 #define QCOW2_OPT_OVERLAP_INACTIVE_L1 "overlap-check.inactive-l1"
119 #define QCOW2_OPT_OVERLAP_INACTIVE_L2 "overlap-check.inactive-l2"
120 #define QCOW2_OPT_OVERLAP_BITMAP_DIRECTORY "overlap-check.bitmap-directory"
121 #define QCOW2_OPT_CACHE_SIZE "cache-size"
122 #define QCOW2_OPT_L2_CACHE_SIZE "l2-cache-size"
123 #define QCOW2_OPT_L2_CACHE_ENTRY_SIZE "l2-cache-entry-size"
124 #define QCOW2_OPT_REFCOUNT_CACHE_SIZE "refcount-cache-size"
125 #define QCOW2_OPT_CACHE_CLEAN_INTERVAL "cache-clean-interval"
126
127 typedef struct QCowHeader {
128 uint32_t magic;
129 uint32_t version;
130 uint64_t backing_file_offset;
131 uint32_t backing_file_size;
132 uint32_t cluster_bits;
133 uint64_t size; /* in bytes */
134 uint32_t crypt_method;
135 uint32_t l1_size; /* XXX: save number of clusters instead ? */
136 uint64_t l1_table_offset;
137 uint64_t refcount_table_offset;
138 uint32_t refcount_table_clusters;
139 uint32_t nb_snapshots;
140 uint64_t snapshots_offset;
141
142 /* The following fields are only valid for version >= 3 */
143 uint64_t incompatible_features;
144 uint64_t compatible_features;
145 uint64_t autoclear_features;
146
147 uint32_t refcount_order;
148 uint32_t header_length;
149 } QEMU_PACKED QCowHeader;
150
151 typedef struct QEMU_PACKED QCowSnapshotHeader {
152 /* header is 8 byte aligned */
153 uint64_t l1_table_offset;
154
155 uint32_t l1_size;
156 uint16_t id_str_size;
157 uint16_t name_size;
158
159 uint32_t date_sec;
160 uint32_t date_nsec;
161
162 uint64_t vm_clock_nsec;
163
164 uint32_t vm_state_size;
165 uint32_t extra_data_size; /* for extension */
166 /* extra data follows */
167 /* id_str follows */
168 /* name follows */
169 } QCowSnapshotHeader;
170
171 typedef struct QEMU_PACKED QCowSnapshotExtraData {
172 uint64_t vm_state_size_large;
173 uint64_t disk_size;
174 } QCowSnapshotExtraData;
175
176
177 typedef struct QCowSnapshot {
178 uint64_t l1_table_offset;
179 uint32_t l1_size;
180 char *id_str;
181 char *name;
182 uint64_t disk_size;
183 uint64_t vm_state_size;
184 uint32_t date_sec;
185 uint32_t date_nsec;
186 uint64_t vm_clock_nsec;
187 /* Size of all extra data, including QCowSnapshotExtraData if available */
188 uint32_t extra_data_size;
189 /* Data beyond QCowSnapshotExtraData, if any */
190 void *unknown_extra_data;
191 } QCowSnapshot;
192
193 struct Qcow2Cache;
194 typedef struct Qcow2Cache Qcow2Cache;
195
196 typedef struct Qcow2CryptoHeaderExtension {
197 uint64_t offset;
198 uint64_t length;
199 } QEMU_PACKED Qcow2CryptoHeaderExtension;
200
201 typedef struct Qcow2UnknownHeaderExtension {
202 uint32_t magic;
203 uint32_t len;
204 QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
205 uint8_t data[];
206 } Qcow2UnknownHeaderExtension;
207
208 enum {
209 QCOW2_FEAT_TYPE_INCOMPATIBLE = 0,
210 QCOW2_FEAT_TYPE_COMPATIBLE = 1,
211 QCOW2_FEAT_TYPE_AUTOCLEAR = 2,
212 };
213
214 /* Incompatible feature bits */
215 enum {
216 QCOW2_INCOMPAT_DIRTY_BITNR = 0,
217 QCOW2_INCOMPAT_CORRUPT_BITNR = 1,
218 QCOW2_INCOMPAT_DATA_FILE_BITNR = 2,
219 QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
220 QCOW2_INCOMPAT_CORRUPT = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
221 QCOW2_INCOMPAT_DATA_FILE = 1 << QCOW2_INCOMPAT_DATA_FILE_BITNR,
222
223 QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY
224 | QCOW2_INCOMPAT_CORRUPT
225 | QCOW2_INCOMPAT_DATA_FILE,
226 };
227
228 /* Compatible feature bits */
229 enum {
230 QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
231 QCOW2_COMPAT_LAZY_REFCOUNTS = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
232
233 QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS,
234 };
235
236 /* Autoclear feature bits */
237 enum {
238 QCOW2_AUTOCLEAR_BITMAPS_BITNR = 0,
239 QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR = 1,
240 QCOW2_AUTOCLEAR_BITMAPS = 1 << QCOW2_AUTOCLEAR_BITMAPS_BITNR,
241 QCOW2_AUTOCLEAR_DATA_FILE_RAW = 1 << QCOW2_AUTOCLEAR_DATA_FILE_RAW_BITNR,
242
243 QCOW2_AUTOCLEAR_MASK = QCOW2_AUTOCLEAR_BITMAPS
244 | QCOW2_AUTOCLEAR_DATA_FILE_RAW,
245 };
246
247 enum qcow2_discard_type {
248 QCOW2_DISCARD_NEVER = 0,
249 QCOW2_DISCARD_ALWAYS,
250 QCOW2_DISCARD_REQUEST,
251 QCOW2_DISCARD_SNAPSHOT,
252 QCOW2_DISCARD_OTHER,
253 QCOW2_DISCARD_MAX
254 };
255
256 typedef struct Qcow2Feature {
257 uint8_t type;
258 uint8_t bit;
259 char name[46];
260 } QEMU_PACKED Qcow2Feature;
261
262 typedef struct Qcow2DiscardRegion {
263 BlockDriverState *bs;
264 uint64_t offset;
265 uint64_t bytes;
266 QTAILQ_ENTRY(Qcow2DiscardRegion) next;
267 } Qcow2DiscardRegion;
268
269 typedef uint64_t Qcow2GetRefcountFunc(const void *refcount_array,
270 uint64_t index);
271 typedef void Qcow2SetRefcountFunc(void *refcount_array,
272 uint64_t index, uint64_t value);
273
274 typedef struct Qcow2BitmapHeaderExt {
275 uint32_t nb_bitmaps;
276 uint32_t reserved32;
277 uint64_t bitmap_directory_size;
278 uint64_t bitmap_directory_offset;
279 } QEMU_PACKED Qcow2BitmapHeaderExt;
280
281 #define QCOW2_MAX_THREADS 4
282
283 typedef struct BDRVQcow2State {
284 int cluster_bits;
285 int cluster_size;
286 int l2_slice_size;
287 int l2_bits;
288 int l2_size;
289 int l1_size;
290 int l1_vm_state_index;
291 int refcount_block_bits;
292 int refcount_block_size;
293 int csize_shift;
294 int csize_mask;
295 uint64_t cluster_offset_mask;
296 uint64_t l1_table_offset;
297 uint64_t *l1_table;
298
299 Qcow2Cache* l2_table_cache;
300 Qcow2Cache* refcount_block_cache;
301 QEMUTimer *cache_clean_timer;
302 unsigned cache_clean_interval;
303
304 uint8_t *cluster_cache;
305 uint8_t *cluster_data;
306 uint64_t cluster_cache_offset;
307 QLIST_HEAD(, QCowL2Meta) cluster_allocs;
308
309 uint64_t *refcount_table;
310 uint64_t refcount_table_offset;
311 uint32_t refcount_table_size;
312 uint32_t max_refcount_table_index; /* Last used entry in refcount_table */
313 uint64_t free_cluster_index;
314 uint64_t free_byte_offset;
315
316 CoMutex lock;
317
318 Qcow2CryptoHeaderExtension crypto_header; /* QCow2 header extension */
319 QCryptoBlockOpenOptions *crypto_opts; /* Disk encryption runtime options */
320 QCryptoBlock *crypto; /* Disk encryption format driver */
321 bool crypt_physical_offset; /* Whether to use virtual or physical offset
322 for encryption initialization vector tweak */
323 uint32_t crypt_method_header;
324 uint64_t snapshots_offset;
325 int snapshots_size;
326 unsigned int nb_snapshots;
327 QCowSnapshot *snapshots;
328
329 uint32_t nb_bitmaps;
330 uint64_t bitmap_directory_size;
331 uint64_t bitmap_directory_offset;
332
333 int flags;
334 int qcow_version;
335 bool use_lazy_refcounts;
336 int refcount_order;
337 int refcount_bits;
338 uint64_t refcount_max;
339
340 Qcow2GetRefcountFunc *get_refcount;
341 Qcow2SetRefcountFunc *set_refcount;
342
343 bool discard_passthrough[QCOW2_DISCARD_MAX];
344
345 int overlap_check; /* bitmask of Qcow2MetadataOverlap values */
346 bool signaled_corruption;
347
348 uint64_t incompatible_features;
349 uint64_t compatible_features;
350 uint64_t autoclear_features;
351
352 size_t unknown_header_fields_size;
353 void* unknown_header_fields;
354 QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
355 QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
356 bool cache_discards;
357
358 /* Backing file path and format as stored in the image (this is not the
359 * effective path/format, which may be the result of a runtime option
360 * override) */
361 char *image_backing_file;
362 char *image_backing_format;
363 char *image_data_file;
364
365 CoQueue thread_task_queue;
366 int nb_threads;
367
368 BdrvChild *data_file;
369
370 bool metadata_preallocation_checked;
371 bool metadata_preallocation;
372 } BDRVQcow2State;
373
374 typedef struct Qcow2COWRegion {
375 /**
376 * Offset of the COW region in bytes from the start of the first cluster
377 * touched by the request.
378 */
379 unsigned offset;
380
381 /** Number of bytes to copy */
382 unsigned nb_bytes;
383 } Qcow2COWRegion;
384
385 /**
386 * Describes an in-flight (part of a) write request that writes to clusters
387 * that are not referenced in their L2 table yet.
388 */
389 typedef struct QCowL2Meta
390 {
391 /** Guest offset of the first newly allocated cluster */
392 uint64_t offset;
393
394 /** Host offset of the first newly allocated cluster */
395 uint64_t alloc_offset;
396
397 /** Number of newly allocated clusters */
398 int nb_clusters;
399
400 /** Do not free the old clusters */
401 bool keep_old_clusters;
402
403 /**
404 * Requests that overlap with this allocation and wait to be restarted
405 * when the allocating request has completed.
406 */
407 CoQueue dependent_requests;
408
409 /**
410 * The COW Region between the start of the first allocated cluster and the
411 * area the guest actually writes to.
412 */
413 Qcow2COWRegion cow_start;
414
415 /**
416 * The COW Region between the area the guest actually writes to and the
417 * end of the last allocated cluster.
418 */
419 Qcow2COWRegion cow_end;
420
421 /*
422 * Indicates that COW regions are already handled and do not require
423 * any more processing.
424 */
425 bool skip_cow;
426
427 /**
428 * The I/O vector with the data from the actual guest write request.
429 * If non-NULL, this is meant to be merged together with the data
430 * from @cow_start and @cow_end into one single write operation.
431 */
432 QEMUIOVector *data_qiov;
433 size_t data_qiov_offset;
434
435 /** Pointer to next L2Meta of the same write request */
436 struct QCowL2Meta *next;
437
438 QLIST_ENTRY(QCowL2Meta) next_in_flight;
439 } QCowL2Meta;
440
441 typedef enum QCow2ClusterType {
442 QCOW2_CLUSTER_UNALLOCATED,
443 QCOW2_CLUSTER_ZERO_PLAIN,
444 QCOW2_CLUSTER_ZERO_ALLOC,
445 QCOW2_CLUSTER_NORMAL,
446 QCOW2_CLUSTER_COMPRESSED,
447 } QCow2ClusterType;
448
449 typedef enum QCow2MetadataOverlap {
450 QCOW2_OL_MAIN_HEADER_BITNR = 0,
451 QCOW2_OL_ACTIVE_L1_BITNR = 1,
452 QCOW2_OL_ACTIVE_L2_BITNR = 2,
453 QCOW2_OL_REFCOUNT_TABLE_BITNR = 3,
454 QCOW2_OL_REFCOUNT_BLOCK_BITNR = 4,
455 QCOW2_OL_SNAPSHOT_TABLE_BITNR = 5,
456 QCOW2_OL_INACTIVE_L1_BITNR = 6,
457 QCOW2_OL_INACTIVE_L2_BITNR = 7,
458 QCOW2_OL_BITMAP_DIRECTORY_BITNR = 8,
459
460 QCOW2_OL_MAX_BITNR = 9,
461
462 QCOW2_OL_NONE = 0,
463 QCOW2_OL_MAIN_HEADER = (1 << QCOW2_OL_MAIN_HEADER_BITNR),
464 QCOW2_OL_ACTIVE_L1 = (1 << QCOW2_OL_ACTIVE_L1_BITNR),
465 QCOW2_OL_ACTIVE_L2 = (1 << QCOW2_OL_ACTIVE_L2_BITNR),
466 QCOW2_OL_REFCOUNT_TABLE = (1 << QCOW2_OL_REFCOUNT_TABLE_BITNR),
467 QCOW2_OL_REFCOUNT_BLOCK = (1 << QCOW2_OL_REFCOUNT_BLOCK_BITNR),
468 QCOW2_OL_SNAPSHOT_TABLE = (1 << QCOW2_OL_SNAPSHOT_TABLE_BITNR),
469 QCOW2_OL_INACTIVE_L1 = (1 << QCOW2_OL_INACTIVE_L1_BITNR),
470 /* NOTE: Checking overlaps with inactive L2 tables will result in bdrv
471 * reads. */
472 QCOW2_OL_INACTIVE_L2 = (1 << QCOW2_OL_INACTIVE_L2_BITNR),
473 QCOW2_OL_BITMAP_DIRECTORY = (1 << QCOW2_OL_BITMAP_DIRECTORY_BITNR),
474 } QCow2MetadataOverlap;
475
476 /* Perform all overlap checks which can be done in constant time */
477 #define QCOW2_OL_CONSTANT \
478 (QCOW2_OL_MAIN_HEADER | QCOW2_OL_ACTIVE_L1 | QCOW2_OL_REFCOUNT_TABLE | \
479 QCOW2_OL_SNAPSHOT_TABLE | QCOW2_OL_BITMAP_DIRECTORY)
480
481 /* Perform all overlap checks which don't require disk access */
482 #define QCOW2_OL_CACHED \
483 (QCOW2_OL_CONSTANT | QCOW2_OL_ACTIVE_L2 | QCOW2_OL_REFCOUNT_BLOCK | \
484 QCOW2_OL_INACTIVE_L1)
485
486 /* Perform all overlap checks */
487 #define QCOW2_OL_ALL \
488 (QCOW2_OL_CACHED | QCOW2_OL_INACTIVE_L2)
489
490 #define L1E_OFFSET_MASK 0x00fffffffffffe00ULL
491 #define L2E_OFFSET_MASK 0x00fffffffffffe00ULL
492 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
493
494 #define REFT_OFFSET_MASK 0xfffffffffffffe00ULL
495
496 #define INV_OFFSET (-1ULL)
497
has_data_file(BlockDriverState * bs)498 static inline bool has_data_file(BlockDriverState *bs)
499 {
500 BDRVQcow2State *s = bs->opaque;
501 return (s->data_file != bs->file);
502 }
503
data_file_is_raw(BlockDriverState * bs)504 static inline bool data_file_is_raw(BlockDriverState *bs)
505 {
506 BDRVQcow2State *s = bs->opaque;
507 return !!(s->autoclear_features & QCOW2_AUTOCLEAR_DATA_FILE_RAW);
508 }
509
start_of_cluster(BDRVQcow2State * s,int64_t offset)510 static inline int64_t start_of_cluster(BDRVQcow2State *s, int64_t offset)
511 {
512 return offset & ~(s->cluster_size - 1);
513 }
514
offset_into_cluster(BDRVQcow2State * s,int64_t offset)515 static inline int64_t offset_into_cluster(BDRVQcow2State *s, int64_t offset)
516 {
517 return offset & (s->cluster_size - 1);
518 }
519
size_to_clusters(BDRVQcow2State * s,uint64_t size)520 static inline uint64_t size_to_clusters(BDRVQcow2State *s, uint64_t size)
521 {
522 return (size + (s->cluster_size - 1)) >> s->cluster_bits;
523 }
524
size_to_l1(BDRVQcow2State * s,int64_t size)525 static inline int64_t size_to_l1(BDRVQcow2State *s, int64_t size)
526 {
527 int shift = s->cluster_bits + s->l2_bits;
528 return (size + (1ULL << shift) - 1) >> shift;
529 }
530
offset_to_l1_index(BDRVQcow2State * s,uint64_t offset)531 static inline int offset_to_l1_index(BDRVQcow2State *s, uint64_t offset)
532 {
533 return offset >> (s->l2_bits + s->cluster_bits);
534 }
535
offset_to_l2_index(BDRVQcow2State * s,int64_t offset)536 static inline int offset_to_l2_index(BDRVQcow2State *s, int64_t offset)
537 {
538 return (offset >> s->cluster_bits) & (s->l2_size - 1);
539 }
540
offset_to_l2_slice_index(BDRVQcow2State * s,int64_t offset)541 static inline int offset_to_l2_slice_index(BDRVQcow2State *s, int64_t offset)
542 {
543 return (offset >> s->cluster_bits) & (s->l2_slice_size - 1);
544 }
545
qcow2_vm_state_offset(BDRVQcow2State * s)546 static inline int64_t qcow2_vm_state_offset(BDRVQcow2State *s)
547 {
548 return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
549 }
550
qcow2_get_cluster_type(BlockDriverState * bs,uint64_t l2_entry)551 static inline QCow2ClusterType qcow2_get_cluster_type(BlockDriverState *bs,
552 uint64_t l2_entry)
553 {
554 if (l2_entry & QCOW_OFLAG_COMPRESSED) {
555 return QCOW2_CLUSTER_COMPRESSED;
556 } else if (l2_entry & QCOW_OFLAG_ZERO) {
557 if (l2_entry & L2E_OFFSET_MASK) {
558 return QCOW2_CLUSTER_ZERO_ALLOC;
559 }
560 return QCOW2_CLUSTER_ZERO_PLAIN;
561 } else if (!(l2_entry & L2E_OFFSET_MASK)) {
562 /* Offset 0 generally means unallocated, but it is ambiguous with
563 * external data files because 0 is a valid offset there. However, all
564 * clusters in external data files always have refcount 1, so we can
565 * rely on QCOW_OFLAG_COPIED to disambiguate. */
566 if (has_data_file(bs) && (l2_entry & QCOW_OFLAG_COPIED)) {
567 return QCOW2_CLUSTER_NORMAL;
568 } else {
569 return QCOW2_CLUSTER_UNALLOCATED;
570 }
571 } else {
572 return QCOW2_CLUSTER_NORMAL;
573 }
574 }
575
576 /* Check whether refcounts are eager or lazy */
qcow2_need_accurate_refcounts(BDRVQcow2State * s)577 static inline bool qcow2_need_accurate_refcounts(BDRVQcow2State *s)
578 {
579 return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
580 }
581
l2meta_cow_start(QCowL2Meta * m)582 static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
583 {
584 return m->offset + m->cow_start.offset;
585 }
586
l2meta_cow_end(QCowL2Meta * m)587 static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
588 {
589 return m->offset + m->cow_end.offset + m->cow_end.nb_bytes;
590 }
591
refcount_diff(uint64_t r1,uint64_t r2)592 static inline uint64_t refcount_diff(uint64_t r1, uint64_t r2)
593 {
594 return r1 > r2 ? r1 - r2 : r2 - r1;
595 }
596
597 static inline
offset_to_reftable_index(BDRVQcow2State * s,uint64_t offset)598 uint32_t offset_to_reftable_index(BDRVQcow2State *s, uint64_t offset)
599 {
600 return offset >> (s->refcount_block_bits + s->cluster_bits);
601 }
602
603 /* qcow2.c functions */
604 int64_t qcow2_refcount_metadata_size(int64_t clusters, size_t cluster_size,
605 int refcount_order, bool generous_increase,
606 uint64_t *refblock_count);
607
608 int qcow2_mark_dirty(BlockDriverState *bs);
609 int qcow2_mark_corrupt(BlockDriverState *bs);
610 int qcow2_mark_consistent(BlockDriverState *bs);
611 int qcow2_update_header(BlockDriverState *bs);
612
613 void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
614 int64_t size, const char *message_format, ...)
615 GCC_FMT_ATTR(5, 6);
616
617 int qcow2_validate_table(BlockDriverState *bs, uint64_t offset,
618 uint64_t entries, size_t entry_len,
619 int64_t max_size_bytes, const char *table_name,
620 Error **errp);
621
622 /* qcow2-refcount.c functions */
623 int qcow2_refcount_init(BlockDriverState *bs);
624 void qcow2_refcount_close(BlockDriverState *bs);
625
626 int qcow2_get_refcount(BlockDriverState *bs, int64_t cluster_index,
627 uint64_t *refcount);
628
629 int qcow2_update_cluster_refcount(BlockDriverState *bs, int64_t cluster_index,
630 uint64_t addend, bool decrease,
631 enum qcow2_discard_type type);
632
633 int64_t qcow2_refcount_area(BlockDriverState *bs, uint64_t offset,
634 uint64_t additional_clusters, bool exact_size,
635 int new_refblock_index,
636 uint64_t new_refblock_offset);
637
638 int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size);
639 int64_t qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
640 int64_t nb_clusters);
641 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
642 void qcow2_free_clusters(BlockDriverState *bs,
643 int64_t offset, int64_t size,
644 enum qcow2_discard_type type);
645 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
646 int nb_clusters, enum qcow2_discard_type type);
647
648 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
649 int64_t l1_table_offset, int l1_size, int addend);
650
651 int coroutine_fn qcow2_flush_caches(BlockDriverState *bs);
652 int coroutine_fn qcow2_write_caches(BlockDriverState *bs);
653 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
654 BdrvCheckMode fix);
655
656 void qcow2_process_discards(BlockDriverState *bs, int ret);
657
658 int qcow2_check_metadata_overlap(BlockDriverState *bs, int ign, int64_t offset,
659 int64_t size);
660 int qcow2_pre_write_overlap_check(BlockDriverState *bs, int ign, int64_t offset,
661 int64_t size, bool data_file);
662 int qcow2_inc_refcounts_imrt(BlockDriverState *bs, BdrvCheckResult *res,
663 void **refcount_table,
664 int64_t *refcount_table_size,
665 int64_t offset, int64_t size);
666
667 int qcow2_change_refcount_order(BlockDriverState *bs, int refcount_order,
668 BlockDriverAmendStatusCB *status_cb,
669 void *cb_opaque, Error **errp);
670 int qcow2_shrink_reftable(BlockDriverState *bs);
671 int64_t qcow2_get_last_cluster(BlockDriverState *bs, int64_t size);
672 int qcow2_detect_metadata_preallocation(BlockDriverState *bs);
673
674 /* qcow2-cluster.c functions */
675 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
676 bool exact_size);
677 int qcow2_shrink_l1_table(BlockDriverState *bs, uint64_t max_size);
678 int qcow2_write_l1_entry(BlockDriverState *bs, int l1_index);
679 int qcow2_encrypt_sectors(BDRVQcow2State *s, int64_t sector_num,
680 uint8_t *buf, int nb_sectors, bool enc, Error **errp);
681
682 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
683 unsigned int *bytes, uint64_t *cluster_offset);
684 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
685 unsigned int *bytes, uint64_t *host_offset,
686 QCowL2Meta **m);
687 int qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
688 uint64_t offset,
689 int compressed_size,
690 uint64_t *host_offset);
691
692 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
693 void qcow2_alloc_cluster_abort(BlockDriverState *bs, QCowL2Meta *m);
694 int qcow2_cluster_discard(BlockDriverState *bs, uint64_t offset,
695 uint64_t bytes, enum qcow2_discard_type type,
696 bool full_discard);
697 int qcow2_cluster_zeroize(BlockDriverState *bs, uint64_t offset,
698 uint64_t bytes, int flags);
699
700 int qcow2_expand_zero_clusters(BlockDriverState *bs,
701 BlockDriverAmendStatusCB *status_cb,
702 void *cb_opaque);
703
704 /* qcow2-snapshot.c functions */
705 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
706 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
707 int qcow2_snapshot_delete(BlockDriverState *bs,
708 const char *snapshot_id,
709 const char *name,
710 Error **errp);
711 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
712 int qcow2_snapshot_load_tmp(BlockDriverState *bs,
713 const char *snapshot_id,
714 const char *name,
715 Error **errp);
716
717 void qcow2_free_snapshots(BlockDriverState *bs);
718 int qcow2_read_snapshots(BlockDriverState *bs, Error **errp);
719 int qcow2_write_snapshots(BlockDriverState *bs);
720
721 int coroutine_fn qcow2_check_read_snapshot_table(BlockDriverState *bs,
722 BdrvCheckResult *result,
723 BdrvCheckMode fix);
724 int coroutine_fn qcow2_check_fix_snapshot_table(BlockDriverState *bs,
725 BdrvCheckResult *result,
726 BdrvCheckMode fix);
727
728 /* qcow2-cache.c functions */
729 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables,
730 unsigned table_size);
731 int qcow2_cache_destroy(Qcow2Cache *c);
732
733 void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
734 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
735 int qcow2_cache_write(BlockDriverState *bs, Qcow2Cache *c);
736 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
737 Qcow2Cache *dependency);
738 void qcow2_cache_depends_on_flush(Qcow2Cache *c);
739
740 void qcow2_cache_clean_unused(Qcow2Cache *c);
741 int qcow2_cache_empty(BlockDriverState *bs, Qcow2Cache *c);
742
743 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
744 void **table);
745 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
746 void **table);
747 void qcow2_cache_put(Qcow2Cache *c, void **table);
748 void *qcow2_cache_is_table_offset(Qcow2Cache *c, uint64_t offset);
749 void qcow2_cache_discard(Qcow2Cache *c, void *table);
750
751 /* qcow2-bitmap.c functions */
752 int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
753 void **refcount_table,
754 int64_t *refcount_table_size);
755 bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp);
756 Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs,
757 Error **errp);
758 int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp);
759 int qcow2_truncate_bitmaps_check(BlockDriverState *bs, Error **errp);
760 void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs,
761 bool release_stored, Error **errp);
762 int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp);
763 bool qcow2_co_can_store_new_dirty_bitmap(BlockDriverState *bs,
764 const char *name,
765 uint32_t granularity,
766 Error **errp);
767 int qcow2_co_remove_persistent_dirty_bitmap(BlockDriverState *bs,
768 const char *name,
769 Error **errp);
770
771 ssize_t coroutine_fn
772 qcow2_co_compress(BlockDriverState *bs, void *dest, size_t dest_size,
773 const void *src, size_t src_size);
774 ssize_t coroutine_fn
775 qcow2_co_decompress(BlockDriverState *bs, void *dest, size_t dest_size,
776 const void *src, size_t src_size);
777 int coroutine_fn
778 qcow2_co_encrypt(BlockDriverState *bs, uint64_t host_offset,
779 uint64_t guest_offset, void *buf, size_t len);
780 int coroutine_fn
781 qcow2_co_decrypt(BlockDriverState *bs, uint64_t host_offset,
782 uint64_t guest_offset, void *buf, size_t len);
783
784 #endif
785