configure: Don't say target_nptl="no" if there is no linux-user target
[qemu/ar7.git] / block / qcow2.h
blob3b2d5cda71f7e6bfbd8c9f065cd698b4d9099a2f
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
42 /* indicate that the refcount of the referenced cluster is exactly one. */
43 #define QCOW_OFLAG_COPIED (1LL << 63)
44 /* indicate that the cluster is compressed (they never have the copied flag) */
45 #define QCOW_OFLAG_COMPRESSED (1LL << 62)
46 /* The cluster reads as all zeros */
47 #define QCOW_OFLAG_ZERO (1LL << 0)
49 #define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */
51 #define MIN_CLUSTER_BITS 9
52 #define MAX_CLUSTER_BITS 21
54 #define L2_CACHE_SIZE 16
56 /* Must be at least 4 to cover all cases of refcount table growth */
57 #define REFCOUNT_CACHE_SIZE 4
59 #define DEFAULT_CLUSTER_SIZE 65536
62 #define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts"
63 #define QCOW2_OPT_DISCARD_REQUEST "pass_discard_request"
64 #define QCOW2_OPT_DISCARD_SNAPSHOT "pass_discard_snapshot"
65 #define QCOW2_OPT_DISCARD_OTHER "pass_discard_other"
67 typedef struct QCowHeader {
68 uint32_t magic;
69 uint32_t version;
70 uint64_t backing_file_offset;
71 uint32_t backing_file_size;
72 uint32_t cluster_bits;
73 uint64_t size; /* in bytes */
74 uint32_t crypt_method;
75 uint32_t l1_size; /* XXX: save number of clusters instead ? */
76 uint64_t l1_table_offset;
77 uint64_t refcount_table_offset;
78 uint32_t refcount_table_clusters;
79 uint32_t nb_snapshots;
80 uint64_t snapshots_offset;
82 /* The following fields are only valid for version >= 3 */
83 uint64_t incompatible_features;
84 uint64_t compatible_features;
85 uint64_t autoclear_features;
87 uint32_t refcount_order;
88 uint32_t header_length;
89 } QCowHeader;
91 typedef struct QCowSnapshot {
92 uint64_t l1_table_offset;
93 uint32_t l1_size;
94 char *id_str;
95 char *name;
96 uint64_t disk_size;
97 uint64_t vm_state_size;
98 uint32_t date_sec;
99 uint32_t date_nsec;
100 uint64_t vm_clock_nsec;
101 } QCowSnapshot;
103 struct Qcow2Cache;
104 typedef struct Qcow2Cache Qcow2Cache;
106 typedef struct Qcow2UnknownHeaderExtension {
107 uint32_t magic;
108 uint32_t len;
109 QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
110 uint8_t data[];
111 } Qcow2UnknownHeaderExtension;
113 enum {
114 QCOW2_FEAT_TYPE_INCOMPATIBLE = 0,
115 QCOW2_FEAT_TYPE_COMPATIBLE = 1,
116 QCOW2_FEAT_TYPE_AUTOCLEAR = 2,
119 /* Incompatible feature bits */
120 enum {
121 QCOW2_INCOMPAT_DIRTY_BITNR = 0,
122 QCOW2_INCOMPAT_DIRTY = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
124 QCOW2_INCOMPAT_MASK = QCOW2_INCOMPAT_DIRTY,
127 /* Compatible feature bits */
128 enum {
129 QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
130 QCOW2_COMPAT_LAZY_REFCOUNTS = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
132 QCOW2_COMPAT_FEAT_MASK = QCOW2_COMPAT_LAZY_REFCOUNTS,
135 enum qcow2_discard_type {
136 QCOW2_DISCARD_NEVER = 0,
137 QCOW2_DISCARD_ALWAYS,
138 QCOW2_DISCARD_REQUEST,
139 QCOW2_DISCARD_SNAPSHOT,
140 QCOW2_DISCARD_OTHER,
141 QCOW2_DISCARD_MAX
144 typedef struct Qcow2Feature {
145 uint8_t type;
146 uint8_t bit;
147 char name[46];
148 } QEMU_PACKED Qcow2Feature;
150 typedef struct Qcow2DiscardRegion {
151 BlockDriverState *bs;
152 uint64_t offset;
153 uint64_t bytes;
154 QTAILQ_ENTRY(Qcow2DiscardRegion) next;
155 } Qcow2DiscardRegion;
157 typedef struct BDRVQcowState {
158 int cluster_bits;
159 int cluster_size;
160 int cluster_sectors;
161 int l2_bits;
162 int l2_size;
163 int l1_size;
164 int l1_vm_state_index;
165 int csize_shift;
166 int csize_mask;
167 uint64_t cluster_offset_mask;
168 uint64_t l1_table_offset;
169 uint64_t *l1_table;
171 Qcow2Cache* l2_table_cache;
172 Qcow2Cache* refcount_block_cache;
174 uint8_t *cluster_cache;
175 uint8_t *cluster_data;
176 uint64_t cluster_cache_offset;
177 QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
179 uint64_t *refcount_table;
180 uint64_t refcount_table_offset;
181 uint32_t refcount_table_size;
182 int64_t free_cluster_index;
183 int64_t free_byte_offset;
185 CoMutex lock;
187 uint32_t crypt_method; /* current crypt method, 0 if no key yet */
188 uint32_t crypt_method_header;
189 AES_KEY aes_encrypt_key;
190 AES_KEY aes_decrypt_key;
191 uint64_t snapshots_offset;
192 int snapshots_size;
193 int nb_snapshots;
194 QCowSnapshot *snapshots;
196 int flags;
197 int qcow_version;
198 bool use_lazy_refcounts;
200 bool discard_passthrough[QCOW2_DISCARD_MAX];
202 uint64_t incompatible_features;
203 uint64_t compatible_features;
204 uint64_t autoclear_features;
206 size_t unknown_header_fields_size;
207 void* unknown_header_fields;
208 QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
209 QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
210 bool cache_discards;
211 } BDRVQcowState;
213 /* XXX: use std qcow open function ? */
214 typedef struct QCowCreateState {
215 int cluster_size;
216 int cluster_bits;
217 uint16_t *refcount_block;
218 uint64_t *refcount_table;
219 int64_t l1_table_offset;
220 int64_t refcount_table_offset;
221 int64_t refcount_block_offset;
222 } QCowCreateState;
224 struct QCowAIOCB;
226 typedef struct Qcow2COWRegion {
228 * Offset of the COW region in bytes from the start of the first cluster
229 * touched by the request.
231 uint64_t offset;
233 /** Number of sectors to copy */
234 int nb_sectors;
235 } Qcow2COWRegion;
238 * Describes an in-flight (part of a) write request that writes to clusters
239 * that are not referenced in their L2 table yet.
241 typedef struct QCowL2Meta
243 /** Guest offset of the first newly allocated cluster */
244 uint64_t offset;
246 /** Host offset of the first newly allocated cluster */
247 uint64_t alloc_offset;
250 * Number of sectors from the start of the first allocated cluster to
251 * the end of the (possibly shortened) request
253 int nb_available;
255 /** Number of newly allocated clusters */
256 int nb_clusters;
259 * Requests that overlap with this allocation and wait to be restarted
260 * when the allocating request has completed.
262 CoQueue dependent_requests;
265 * The COW Region between the start of the first allocated cluster and the
266 * area the guest actually writes to.
268 Qcow2COWRegion cow_start;
271 * The COW Region between the area the guest actually writes to and the
272 * end of the last allocated cluster.
274 Qcow2COWRegion cow_end;
276 /** Pointer to next L2Meta of the same write request */
277 struct QCowL2Meta *next;
279 QLIST_ENTRY(QCowL2Meta) next_in_flight;
280 } QCowL2Meta;
282 enum {
283 QCOW2_CLUSTER_UNALLOCATED,
284 QCOW2_CLUSTER_NORMAL,
285 QCOW2_CLUSTER_COMPRESSED,
286 QCOW2_CLUSTER_ZERO
289 #define L1E_OFFSET_MASK 0x00ffffffffffff00ULL
290 #define L2E_OFFSET_MASK 0x00ffffffffffff00ULL
291 #define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
293 #define REFT_OFFSET_MASK 0xffffffffffffff00ULL
295 static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset)
297 return offset & ~(s->cluster_size - 1);
300 static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset)
302 return offset & (s->cluster_size - 1);
305 static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
307 return (size + (s->cluster_size - 1)) >> s->cluster_bits;
310 static inline int64_t size_to_l1(BDRVQcowState *s, int64_t size)
312 int shift = s->cluster_bits + s->l2_bits;
313 return (size + (1ULL << shift) - 1) >> shift;
316 static inline int offset_to_l2_index(BDRVQcowState *s, int64_t offset)
318 return (offset >> s->cluster_bits) & (s->l2_size - 1);
321 static inline int64_t align_offset(int64_t offset, int n)
323 offset = (offset + n - 1) & ~(n - 1);
324 return offset;
327 static inline int qcow2_get_cluster_type(uint64_t l2_entry)
329 if (l2_entry & QCOW_OFLAG_COMPRESSED) {
330 return QCOW2_CLUSTER_COMPRESSED;
331 } else if (l2_entry & QCOW_OFLAG_ZERO) {
332 return QCOW2_CLUSTER_ZERO;
333 } else if (!(l2_entry & L2E_OFFSET_MASK)) {
334 return QCOW2_CLUSTER_UNALLOCATED;
335 } else {
336 return QCOW2_CLUSTER_NORMAL;
340 /* Check whether refcounts are eager or lazy */
341 static inline bool qcow2_need_accurate_refcounts(BDRVQcowState *s)
343 return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
346 static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
348 return m->offset + m->cow_start.offset;
351 static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
353 return m->offset + m->cow_end.offset
354 + (m->cow_end.nb_sectors << BDRV_SECTOR_BITS);
357 // FIXME Need qcow2_ prefix to global functions
359 /* qcow2.c functions */
360 int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
361 int64_t sector_num, int nb_sectors);
363 int qcow2_mark_dirty(BlockDriverState *bs);
364 int qcow2_update_header(BlockDriverState *bs);
366 /* qcow2-refcount.c functions */
367 int qcow2_refcount_init(BlockDriverState *bs);
368 void qcow2_refcount_close(BlockDriverState *bs);
370 int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size);
371 int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
372 int nb_clusters);
373 int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
374 void qcow2_free_clusters(BlockDriverState *bs,
375 int64_t offset, int64_t size,
376 enum qcow2_discard_type type);
377 void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
378 int nb_clusters, enum qcow2_discard_type type);
380 int qcow2_update_snapshot_refcount(BlockDriverState *bs,
381 int64_t l1_table_offset, int l1_size, int addend);
383 int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
384 BdrvCheckMode fix);
386 void qcow2_process_discards(BlockDriverState *bs, int ret);
388 /* qcow2-cluster.c functions */
389 int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
390 bool exact_size);
391 void qcow2_l2_cache_reset(BlockDriverState *bs);
392 int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
393 void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
394 uint8_t *out_buf, const uint8_t *in_buf,
395 int nb_sectors, int enc,
396 const AES_KEY *key);
398 int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
399 int *num, uint64_t *cluster_offset);
400 int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
401 int n_start, int n_end, int *num, uint64_t *host_offset, QCowL2Meta **m);
402 uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
403 uint64_t offset,
404 int compressed_size);
406 int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
407 int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
408 int nb_sectors);
409 int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors);
411 /* qcow2-snapshot.c functions */
412 int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
413 int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
414 int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
415 int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
416 int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name);
418 void qcow2_free_snapshots(BlockDriverState *bs);
419 int qcow2_read_snapshots(BlockDriverState *bs);
421 /* qcow2-cache.c functions */
422 Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables);
423 int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
425 void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
426 int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
427 int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
428 Qcow2Cache *dependency);
429 void qcow2_cache_depends_on_flush(Qcow2Cache *c);
431 int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
432 void **table);
433 int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
434 void **table);
435 int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
437 #endif