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
24 #include "qemu-common.h"
25 #include "block_int.h"
29 #include "block/qcow2.h"
30 #include "qemu-error.h"
35 Differences with QCOW:
37 - Support for multiple incremental snapshots.
38 - Memory management by reference counts.
39 - Clusters which have a reference count of one have the bit
40 QCOW_OFLAG_COPIED to optimize write performance.
41 - Size of compressed clusters is stored in sectors to reduce bit usage
42 in the cluster offsets.
43 - Support for storing additional data (such as the VM state) in the
45 - If a backing store is used, the cluster size is not constrained
46 (could be backported to QCOW).
47 - L2 tables have always a size of one cluster.
55 #define QCOW2_EXT_MAGIC_END 0
56 #define QCOW2_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA
57 #define QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857
59 static int qcow2_probe(const uint8_t *buf
, int buf_size
, const char *filename
)
61 const QCowHeader
*cow_header
= (const void *)buf
;
63 if (buf_size
>= sizeof(QCowHeader
) &&
64 be32_to_cpu(cow_header
->magic
) == QCOW_MAGIC
&&
65 be32_to_cpu(cow_header
->version
) >= 2)
73 * read qcow2 extension and fill bs
74 * start reading from start_offset
75 * finish reading upon magic of value 0 or when end_offset reached
76 * unknown magic is skipped (future extension this version knows nothing about)
77 * return 0 upon success, non-0 otherwise
79 static int qcow2_read_extensions(BlockDriverState
*bs
, uint64_t start_offset
,
80 uint64_t end_offset
, void **p_feature_table
)
82 BDRVQcowState
*s
= bs
->opaque
;
88 printf("qcow2_read_extensions: start=%ld end=%ld\n", start_offset
, end_offset
);
90 offset
= start_offset
;
91 while (offset
< end_offset
) {
95 if (offset
> s
->cluster_size
)
96 printf("qcow2_read_extension: suspicious offset %lu\n", offset
);
98 printf("attempting to read extended header in offset %lu\n", offset
);
101 if (bdrv_pread(bs
->file
, offset
, &ext
, sizeof(ext
)) != sizeof(ext
)) {
102 fprintf(stderr
, "qcow2_read_extension: ERROR: "
103 "pread fail from offset %" PRIu64
"\n",
107 be32_to_cpus(&ext
.magic
);
108 be32_to_cpus(&ext
.len
);
109 offset
+= sizeof(ext
);
111 printf("ext.magic = 0x%x\n", ext
.magic
);
113 if (ext
.len
> end_offset
- offset
) {
114 error_report("Header extension too large");
119 case QCOW2_EXT_MAGIC_END
:
122 case QCOW2_EXT_MAGIC_BACKING_FORMAT
:
123 if (ext
.len
>= sizeof(bs
->backing_format
)) {
124 fprintf(stderr
, "ERROR: ext_backing_format: len=%u too large"
126 ext
.len
, sizeof(bs
->backing_format
));
129 if (bdrv_pread(bs
->file
, offset
, bs
->backing_format
,
132 bs
->backing_format
[ext
.len
] = '\0';
134 printf("Qcow2: Got format extension %s\n", bs
->backing_format
);
138 case QCOW2_EXT_MAGIC_FEATURE_TABLE
:
139 if (p_feature_table
!= NULL
) {
140 void* feature_table
= g_malloc0(ext
.len
+ 2 * sizeof(Qcow2Feature
));
141 ret
= bdrv_pread(bs
->file
, offset
, feature_table
, ext
.len
);
146 *p_feature_table
= feature_table
;
151 /* unknown magic - save it in case we need to rewrite the header */
153 Qcow2UnknownHeaderExtension
*uext
;
155 uext
= g_malloc0(sizeof(*uext
) + ext
.len
);
156 uext
->magic
= ext
.magic
;
158 QLIST_INSERT_HEAD(&s
->unknown_header_ext
, uext
, next
);
160 ret
= bdrv_pread(bs
->file
, offset
, uext
->data
, uext
->len
);
168 offset
+= ((ext
.len
+ 7) & ~7);
174 static void cleanup_unknown_header_ext(BlockDriverState
*bs
)
176 BDRVQcowState
*s
= bs
->opaque
;
177 Qcow2UnknownHeaderExtension
*uext
, *next
;
179 QLIST_FOREACH_SAFE(uext
, &s
->unknown_header_ext
, next
, next
) {
180 QLIST_REMOVE(uext
, next
);
185 static void GCC_FMT_ATTR(2, 3) report_unsupported(BlockDriverState
*bs
,
186 const char *fmt
, ...)
192 vsnprintf(msg
, sizeof(msg
), fmt
, ap
);
195 qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE
,
196 bs
->device_name
, "qcow2", msg
);
199 static void report_unsupported_feature(BlockDriverState
*bs
,
200 Qcow2Feature
*table
, uint64_t mask
)
202 while (table
&& table
->name
[0] != '\0') {
203 if (table
->type
== QCOW2_FEAT_TYPE_INCOMPATIBLE
) {
204 if (mask
& (1 << table
->bit
)) {
205 report_unsupported(bs
, "%.46s",table
->name
);
206 mask
&= ~(1 << table
->bit
);
213 report_unsupported(bs
, "Unknown incompatible feature: %" PRIx64
, mask
);
218 * Clears the dirty bit and flushes before if necessary. Only call this
219 * function when there are no pending requests, it does not guard against
220 * concurrent requests dirtying the image.
222 static int qcow2_mark_clean(BlockDriverState
*bs
)
224 BDRVQcowState
*s
= bs
->opaque
;
226 if (s
->incompatible_features
& QCOW2_INCOMPAT_DIRTY
) {
227 int ret
= bdrv_flush(bs
);
232 s
->incompatible_features
&= ~QCOW2_INCOMPAT_DIRTY
;
233 return qcow2_update_header(bs
);
238 static int qcow2_open(BlockDriverState
*bs
, int flags
)
240 BDRVQcowState
*s
= bs
->opaque
;
245 ret
= bdrv_pread(bs
->file
, 0, &header
, sizeof(header
));
249 be32_to_cpus(&header
.magic
);
250 be32_to_cpus(&header
.version
);
251 be64_to_cpus(&header
.backing_file_offset
);
252 be32_to_cpus(&header
.backing_file_size
);
253 be64_to_cpus(&header
.size
);
254 be32_to_cpus(&header
.cluster_bits
);
255 be32_to_cpus(&header
.crypt_method
);
256 be64_to_cpus(&header
.l1_table_offset
);
257 be32_to_cpus(&header
.l1_size
);
258 be64_to_cpus(&header
.refcount_table_offset
);
259 be32_to_cpus(&header
.refcount_table_clusters
);
260 be64_to_cpus(&header
.snapshots_offset
);
261 be32_to_cpus(&header
.nb_snapshots
);
263 if (header
.magic
!= QCOW_MAGIC
) {
267 if (header
.version
< 2 || header
.version
> 3) {
268 report_unsupported(bs
, "QCOW version %d", header
.version
);
273 s
->qcow_version
= header
.version
;
275 /* Initialise version 3 header fields */
276 if (header
.version
== 2) {
277 header
.incompatible_features
= 0;
278 header
.compatible_features
= 0;
279 header
.autoclear_features
= 0;
280 header
.refcount_order
= 4;
281 header
.header_length
= 72;
283 be64_to_cpus(&header
.incompatible_features
);
284 be64_to_cpus(&header
.compatible_features
);
285 be64_to_cpus(&header
.autoclear_features
);
286 be32_to_cpus(&header
.refcount_order
);
287 be32_to_cpus(&header
.header_length
);
290 if (header
.header_length
> sizeof(header
)) {
291 s
->unknown_header_fields_size
= header
.header_length
- sizeof(header
);
292 s
->unknown_header_fields
= g_malloc(s
->unknown_header_fields_size
);
293 ret
= bdrv_pread(bs
->file
, sizeof(header
), s
->unknown_header_fields
,
294 s
->unknown_header_fields_size
);
300 if (header
.backing_file_offset
) {
301 ext_end
= header
.backing_file_offset
;
303 ext_end
= 1 << header
.cluster_bits
;
306 /* Handle feature bits */
307 s
->incompatible_features
= header
.incompatible_features
;
308 s
->compatible_features
= header
.compatible_features
;
309 s
->autoclear_features
= header
.autoclear_features
;
311 if (s
->incompatible_features
& ~QCOW2_INCOMPAT_MASK
) {
312 void *feature_table
= NULL
;
313 qcow2_read_extensions(bs
, header
.header_length
, ext_end
,
315 report_unsupported_feature(bs
, feature_table
,
316 s
->incompatible_features
&
317 ~QCOW2_INCOMPAT_MASK
);
322 /* Check support for various header values */
323 if (header
.refcount_order
!= 4) {
324 report_unsupported(bs
, "%d bit reference counts",
325 1 << header
.refcount_order
);
330 if (header
.cluster_bits
< MIN_CLUSTER_BITS
||
331 header
.cluster_bits
> MAX_CLUSTER_BITS
) {
335 if (header
.crypt_method
> QCOW_CRYPT_AES
) {
339 s
->crypt_method_header
= header
.crypt_method
;
340 if (s
->crypt_method_header
) {
343 s
->cluster_bits
= header
.cluster_bits
;
344 s
->cluster_size
= 1 << s
->cluster_bits
;
345 s
->cluster_sectors
= 1 << (s
->cluster_bits
- 9);
346 s
->l2_bits
= s
->cluster_bits
- 3; /* L2 is always one cluster */
347 s
->l2_size
= 1 << s
->l2_bits
;
348 bs
->total_sectors
= header
.size
/ 512;
349 s
->csize_shift
= (62 - (s
->cluster_bits
- 8));
350 s
->csize_mask
= (1 << (s
->cluster_bits
- 8)) - 1;
351 s
->cluster_offset_mask
= (1LL << s
->csize_shift
) - 1;
352 s
->refcount_table_offset
= header
.refcount_table_offset
;
353 s
->refcount_table_size
=
354 header
.refcount_table_clusters
<< (s
->cluster_bits
- 3);
356 s
->snapshots_offset
= header
.snapshots_offset
;
357 s
->nb_snapshots
= header
.nb_snapshots
;
359 /* read the level 1 table */
360 s
->l1_size
= header
.l1_size
;
361 s
->l1_vm_state_index
= size_to_l1(s
, header
.size
);
362 /* the L1 table must contain at least enough entries to put
364 if (s
->l1_size
< s
->l1_vm_state_index
) {
368 s
->l1_table_offset
= header
.l1_table_offset
;
369 if (s
->l1_size
> 0) {
370 s
->l1_table
= g_malloc0(
371 align_offset(s
->l1_size
* sizeof(uint64_t), 512));
372 ret
= bdrv_pread(bs
->file
, s
->l1_table_offset
, s
->l1_table
,
373 s
->l1_size
* sizeof(uint64_t));
377 for(i
= 0;i
< s
->l1_size
; i
++) {
378 be64_to_cpus(&s
->l1_table
[i
]);
382 /* alloc L2 table/refcount block cache */
383 s
->l2_table_cache
= qcow2_cache_create(bs
, L2_CACHE_SIZE
);
384 s
->refcount_block_cache
= qcow2_cache_create(bs
, REFCOUNT_CACHE_SIZE
);
386 s
->cluster_cache
= g_malloc(s
->cluster_size
);
387 /* one more sector for decompressed data alignment */
388 s
->cluster_data
= qemu_blockalign(bs
, QCOW_MAX_CRYPT_CLUSTERS
* s
->cluster_size
390 s
->cluster_cache_offset
= -1;
393 ret
= qcow2_refcount_init(bs
);
398 QLIST_INIT(&s
->cluster_allocs
);
400 /* read qcow2 extensions */
401 if (qcow2_read_extensions(bs
, header
.header_length
, ext_end
, NULL
)) {
406 /* read the backing file name */
407 if (header
.backing_file_offset
!= 0) {
408 len
= header
.backing_file_size
;
412 ret
= bdrv_pread(bs
->file
, header
.backing_file_offset
,
413 bs
->backing_file
, len
);
417 bs
->backing_file
[len
] = '\0';
420 ret
= qcow2_read_snapshots(bs
);
425 /* Clear unknown autoclear feature bits */
426 if (!bs
->read_only
&& s
->autoclear_features
!= 0) {
427 s
->autoclear_features
= 0;
428 ret
= qcow2_update_header(bs
);
434 /* Initialise locks */
435 qemu_co_mutex_init(&s
->lock
);
437 /* Repair image if dirty */
438 if ((s
->incompatible_features
& QCOW2_INCOMPAT_DIRTY
) &&
440 BdrvCheckResult result
= {0};
442 ret
= qcow2_check_refcounts(bs
, &result
, BDRV_FIX_ERRORS
);
447 ret
= qcow2_mark_clean(bs
);
455 BdrvCheckResult result
= {0};
456 qcow2_check_refcounts(bs
, &result
, 0);
462 g_free(s
->unknown_header_fields
);
463 cleanup_unknown_header_ext(bs
);
464 qcow2_free_snapshots(bs
);
465 qcow2_refcount_close(bs
);
467 if (s
->l2_table_cache
) {
468 qcow2_cache_destroy(bs
, s
->l2_table_cache
);
470 g_free(s
->cluster_cache
);
471 qemu_vfree(s
->cluster_data
);
475 static int qcow2_set_key(BlockDriverState
*bs
, const char *key
)
477 BDRVQcowState
*s
= bs
->opaque
;
481 memset(keybuf
, 0, 16);
485 /* XXX: we could compress the chars to 7 bits to increase
487 for(i
= 0;i
< len
;i
++) {
490 s
->crypt_method
= s
->crypt_method_header
;
492 if (AES_set_encrypt_key(keybuf
, 128, &s
->aes_encrypt_key
) != 0)
494 if (AES_set_decrypt_key(keybuf
, 128, &s
->aes_decrypt_key
) != 0)
504 AES_encrypt(in
, tmp
, &s
->aes_encrypt_key
);
505 AES_decrypt(tmp
, out
, &s
->aes_decrypt_key
);
506 for(i
= 0; i
< 16; i
++)
507 printf(" %02x", tmp
[i
]);
509 for(i
= 0; i
< 16; i
++)
510 printf(" %02x", out
[i
]);
517 static int coroutine_fn
qcow2_co_is_allocated(BlockDriverState
*bs
,
518 int64_t sector_num
, int nb_sectors
, int *pnum
)
520 BDRVQcowState
*s
= bs
->opaque
;
521 uint64_t cluster_offset
;
525 /* FIXME We can get errors here, but the bdrv_co_is_allocated interface
526 * can't pass them on today */
527 qemu_co_mutex_lock(&s
->lock
);
528 ret
= qcow2_get_cluster_offset(bs
, sector_num
<< 9, pnum
, &cluster_offset
);
529 qemu_co_mutex_unlock(&s
->lock
);
534 return (cluster_offset
!= 0);
537 /* handle reading after the end of the backing file */
538 int qcow2_backing_read1(BlockDriverState
*bs
, QEMUIOVector
*qiov
,
539 int64_t sector_num
, int nb_sectors
)
542 if ((sector_num
+ nb_sectors
) <= bs
->total_sectors
)
544 if (sector_num
>= bs
->total_sectors
)
547 n1
= bs
->total_sectors
- sector_num
;
549 qemu_iovec_memset(qiov
, 512 * n1
, 0, 512 * (nb_sectors
- n1
));
554 static coroutine_fn
int qcow2_co_readv(BlockDriverState
*bs
, int64_t sector_num
,
555 int remaining_sectors
, QEMUIOVector
*qiov
)
557 BDRVQcowState
*s
= bs
->opaque
;
558 int index_in_cluster
, n1
;
560 int cur_nr_sectors
; /* number of sectors in current iteration */
561 uint64_t cluster_offset
= 0;
562 uint64_t bytes_done
= 0;
563 QEMUIOVector hd_qiov
;
564 uint8_t *cluster_data
= NULL
;
566 qemu_iovec_init(&hd_qiov
, qiov
->niov
);
568 qemu_co_mutex_lock(&s
->lock
);
570 while (remaining_sectors
!= 0) {
572 /* prepare next request */
573 cur_nr_sectors
= remaining_sectors
;
574 if (s
->crypt_method
) {
575 cur_nr_sectors
= MIN(cur_nr_sectors
,
576 QCOW_MAX_CRYPT_CLUSTERS
* s
->cluster_sectors
);
579 ret
= qcow2_get_cluster_offset(bs
, sector_num
<< 9,
580 &cur_nr_sectors
, &cluster_offset
);
585 index_in_cluster
= sector_num
& (s
->cluster_sectors
- 1);
587 qemu_iovec_reset(&hd_qiov
);
588 qemu_iovec_concat(&hd_qiov
, qiov
, bytes_done
,
589 cur_nr_sectors
* 512);
592 case QCOW2_CLUSTER_UNALLOCATED
:
594 if (bs
->backing_hd
) {
595 /* read from the base image */
596 n1
= qcow2_backing_read1(bs
->backing_hd
, &hd_qiov
,
597 sector_num
, cur_nr_sectors
);
599 BLKDBG_EVENT(bs
->file
, BLKDBG_READ_BACKING_AIO
);
600 qemu_co_mutex_unlock(&s
->lock
);
601 ret
= bdrv_co_readv(bs
->backing_hd
, sector_num
,
603 qemu_co_mutex_lock(&s
->lock
);
609 /* Note: in this case, no need to wait */
610 qemu_iovec_memset(&hd_qiov
, 0, 0, 512 * cur_nr_sectors
);
614 case QCOW2_CLUSTER_ZERO
:
615 if (s
->qcow_version
< 3) {
619 qemu_iovec_memset(&hd_qiov
, 0, 0, 512 * cur_nr_sectors
);
622 case QCOW2_CLUSTER_COMPRESSED
:
623 /* add AIO support for compressed blocks ? */
624 ret
= qcow2_decompress_cluster(bs
, cluster_offset
);
629 qemu_iovec_from_buf(&hd_qiov
, 0,
630 s
->cluster_cache
+ index_in_cluster
* 512,
631 512 * cur_nr_sectors
);
634 case QCOW2_CLUSTER_NORMAL
:
635 if ((cluster_offset
& 511) != 0) {
640 if (s
->crypt_method
) {
642 * For encrypted images, read everything into a temporary
643 * contiguous buffer on which the AES functions can work.
647 qemu_blockalign(bs
, QCOW_MAX_CRYPT_CLUSTERS
* s
->cluster_size
);
650 assert(cur_nr_sectors
<=
651 QCOW_MAX_CRYPT_CLUSTERS
* s
->cluster_sectors
);
652 qemu_iovec_reset(&hd_qiov
);
653 qemu_iovec_add(&hd_qiov
, cluster_data
,
654 512 * cur_nr_sectors
);
657 BLKDBG_EVENT(bs
->file
, BLKDBG_READ_AIO
);
658 qemu_co_mutex_unlock(&s
->lock
);
659 ret
= bdrv_co_readv(bs
->file
,
660 (cluster_offset
>> 9) + index_in_cluster
,
661 cur_nr_sectors
, &hd_qiov
);
662 qemu_co_mutex_lock(&s
->lock
);
666 if (s
->crypt_method
) {
667 qcow2_encrypt_sectors(s
, sector_num
, cluster_data
,
668 cluster_data
, cur_nr_sectors
, 0, &s
->aes_decrypt_key
);
669 qemu_iovec_from_buf(qiov
, bytes_done
,
670 cluster_data
, 512 * cur_nr_sectors
);
675 g_assert_not_reached();
680 remaining_sectors
-= cur_nr_sectors
;
681 sector_num
+= cur_nr_sectors
;
682 bytes_done
+= cur_nr_sectors
* 512;
687 qemu_co_mutex_unlock(&s
->lock
);
689 qemu_iovec_destroy(&hd_qiov
);
690 qemu_vfree(cluster_data
);
695 static void run_dependent_requests(BDRVQcowState
*s
, QCowL2Meta
*m
)
697 /* Take the request off the list of running requests */
698 if (m
->nb_clusters
!= 0) {
699 QLIST_REMOVE(m
, next_in_flight
);
702 /* Restart all dependent requests */
703 if (!qemu_co_queue_empty(&m
->dependent_requests
)) {
704 qemu_co_mutex_unlock(&s
->lock
);
705 qemu_co_queue_restart_all(&m
->dependent_requests
);
706 qemu_co_mutex_lock(&s
->lock
);
710 static coroutine_fn
int qcow2_co_writev(BlockDriverState
*bs
,
712 int remaining_sectors
,
715 BDRVQcowState
*s
= bs
->opaque
;
716 int index_in_cluster
;
719 int cur_nr_sectors
; /* number of sectors in current iteration */
720 uint64_t cluster_offset
;
721 QEMUIOVector hd_qiov
;
722 uint64_t bytes_done
= 0;
723 uint8_t *cluster_data
= NULL
;
724 QCowL2Meta l2meta
= {
728 trace_qcow2_writev_start_req(qemu_coroutine_self(), sector_num
,
731 qemu_co_queue_init(&l2meta
.dependent_requests
);
733 qemu_iovec_init(&hd_qiov
, qiov
->niov
);
735 s
->cluster_cache_offset
= -1; /* disable compressed cache */
737 qemu_co_mutex_lock(&s
->lock
);
739 while (remaining_sectors
!= 0) {
741 trace_qcow2_writev_start_part(qemu_coroutine_self());
742 index_in_cluster
= sector_num
& (s
->cluster_sectors
- 1);
743 n_end
= index_in_cluster
+ remaining_sectors
;
744 if (s
->crypt_method
&&
745 n_end
> QCOW_MAX_CRYPT_CLUSTERS
* s
->cluster_sectors
) {
746 n_end
= QCOW_MAX_CRYPT_CLUSTERS
* s
->cluster_sectors
;
749 ret
= qcow2_alloc_cluster_offset(bs
, sector_num
<< 9,
750 index_in_cluster
, n_end
, &cur_nr_sectors
, &l2meta
);
755 cluster_offset
= l2meta
.cluster_offset
;
756 assert((cluster_offset
& 511) == 0);
758 qemu_iovec_reset(&hd_qiov
);
759 qemu_iovec_concat(&hd_qiov
, qiov
, bytes_done
,
760 cur_nr_sectors
* 512);
762 if (s
->crypt_method
) {
764 cluster_data
= qemu_blockalign(bs
, QCOW_MAX_CRYPT_CLUSTERS
*
768 assert(hd_qiov
.size
<=
769 QCOW_MAX_CRYPT_CLUSTERS
* s
->cluster_size
);
770 qemu_iovec_to_buf(&hd_qiov
, 0, cluster_data
, hd_qiov
.size
);
772 qcow2_encrypt_sectors(s
, sector_num
, cluster_data
,
773 cluster_data
, cur_nr_sectors
, 1, &s
->aes_encrypt_key
);
775 qemu_iovec_reset(&hd_qiov
);
776 qemu_iovec_add(&hd_qiov
, cluster_data
,
777 cur_nr_sectors
* 512);
780 BLKDBG_EVENT(bs
->file
, BLKDBG_WRITE_AIO
);
781 qemu_co_mutex_unlock(&s
->lock
);
782 trace_qcow2_writev_data(qemu_coroutine_self(),
783 (cluster_offset
>> 9) + index_in_cluster
);
784 ret
= bdrv_co_writev(bs
->file
,
785 (cluster_offset
>> 9) + index_in_cluster
,
786 cur_nr_sectors
, &hd_qiov
);
787 qemu_co_mutex_lock(&s
->lock
);
792 ret
= qcow2_alloc_cluster_link_l2(bs
, &l2meta
);
797 run_dependent_requests(s
, &l2meta
);
799 remaining_sectors
-= cur_nr_sectors
;
800 sector_num
+= cur_nr_sectors
;
801 bytes_done
+= cur_nr_sectors
* 512;
802 trace_qcow2_writev_done_part(qemu_coroutine_self(), cur_nr_sectors
);
807 run_dependent_requests(s
, &l2meta
);
809 qemu_co_mutex_unlock(&s
->lock
);
811 qemu_iovec_destroy(&hd_qiov
);
812 qemu_vfree(cluster_data
);
813 trace_qcow2_writev_done_req(qemu_coroutine_self(), ret
);
818 static void qcow2_close(BlockDriverState
*bs
)
820 BDRVQcowState
*s
= bs
->opaque
;
823 qcow2_cache_flush(bs
, s
->l2_table_cache
);
824 qcow2_cache_flush(bs
, s
->refcount_block_cache
);
826 qcow2_mark_clean(bs
);
828 qcow2_cache_destroy(bs
, s
->l2_table_cache
);
829 qcow2_cache_destroy(bs
, s
->refcount_block_cache
);
831 g_free(s
->unknown_header_fields
);
832 cleanup_unknown_header_ext(bs
);
834 g_free(s
->cluster_cache
);
835 qemu_vfree(s
->cluster_data
);
836 qcow2_refcount_close(bs
);
837 qcow2_free_snapshots(bs
);
840 static void qcow2_invalidate_cache(BlockDriverState
*bs
)
842 BDRVQcowState
*s
= bs
->opaque
;
843 int flags
= s
->flags
;
844 AES_KEY aes_encrypt_key
;
845 AES_KEY aes_decrypt_key
;
846 uint32_t crypt_method
= 0;
849 * Backing files are read-only which makes all of their metadata immutable,
850 * that means we don't have to worry about reopening them here.
853 if (s
->crypt_method
) {
854 crypt_method
= s
->crypt_method
;
855 memcpy(&aes_encrypt_key
, &s
->aes_encrypt_key
, sizeof(aes_encrypt_key
));
856 memcpy(&aes_decrypt_key
, &s
->aes_decrypt_key
, sizeof(aes_decrypt_key
));
861 memset(s
, 0, sizeof(BDRVQcowState
));
862 qcow2_open(bs
, flags
);
865 s
->crypt_method
= crypt_method
;
866 memcpy(&s
->aes_encrypt_key
, &aes_encrypt_key
, sizeof(aes_encrypt_key
));
867 memcpy(&s
->aes_decrypt_key
, &aes_decrypt_key
, sizeof(aes_decrypt_key
));
871 static size_t header_ext_add(char *buf
, uint32_t magic
, const void *s
,
872 size_t len
, size_t buflen
)
874 QCowExtension
*ext_backing_fmt
= (QCowExtension
*) buf
;
875 size_t ext_len
= sizeof(QCowExtension
) + ((len
+ 7) & ~7);
877 if (buflen
< ext_len
) {
881 *ext_backing_fmt
= (QCowExtension
) {
882 .magic
= cpu_to_be32(magic
),
883 .len
= cpu_to_be32(len
),
885 memcpy(buf
+ sizeof(QCowExtension
), s
, len
);
891 * Updates the qcow2 header, including the variable length parts of it, i.e.
892 * the backing file name and all extensions. qcow2 was not designed to allow
893 * such changes, so if we run out of space (we can only use the first cluster)
894 * this function may fail.
896 * Returns 0 on success, -errno in error cases.
898 int qcow2_update_header(BlockDriverState
*bs
)
900 BDRVQcowState
*s
= bs
->opaque
;
903 size_t buflen
= s
->cluster_size
;
906 uint32_t refcount_table_clusters
;
907 size_t header_length
;
908 Qcow2UnknownHeaderExtension
*uext
;
910 buf
= qemu_blockalign(bs
, buflen
);
912 /* Header structure */
913 header
= (QCowHeader
*) buf
;
915 if (buflen
< sizeof(*header
)) {
920 header_length
= sizeof(*header
) + s
->unknown_header_fields_size
;
921 total_size
= bs
->total_sectors
* BDRV_SECTOR_SIZE
;
922 refcount_table_clusters
= s
->refcount_table_size
>> (s
->cluster_bits
- 3);
924 *header
= (QCowHeader
) {
925 /* Version 2 fields */
926 .magic
= cpu_to_be32(QCOW_MAGIC
),
927 .version
= cpu_to_be32(s
->qcow_version
),
928 .backing_file_offset
= 0,
929 .backing_file_size
= 0,
930 .cluster_bits
= cpu_to_be32(s
->cluster_bits
),
931 .size
= cpu_to_be64(total_size
),
932 .crypt_method
= cpu_to_be32(s
->crypt_method_header
),
933 .l1_size
= cpu_to_be32(s
->l1_size
),
934 .l1_table_offset
= cpu_to_be64(s
->l1_table_offset
),
935 .refcount_table_offset
= cpu_to_be64(s
->refcount_table_offset
),
936 .refcount_table_clusters
= cpu_to_be32(refcount_table_clusters
),
937 .nb_snapshots
= cpu_to_be32(s
->nb_snapshots
),
938 .snapshots_offset
= cpu_to_be64(s
->snapshots_offset
),
940 /* Version 3 fields */
941 .incompatible_features
= cpu_to_be64(s
->incompatible_features
),
942 .compatible_features
= cpu_to_be64(s
->compatible_features
),
943 .autoclear_features
= cpu_to_be64(s
->autoclear_features
),
944 .refcount_order
= cpu_to_be32(3 + REFCOUNT_SHIFT
),
945 .header_length
= cpu_to_be32(header_length
),
948 /* For older versions, write a shorter header */
949 switch (s
->qcow_version
) {
951 ret
= offsetof(QCowHeader
, incompatible_features
);
954 ret
= sizeof(*header
);
963 memset(buf
, 0, buflen
);
965 /* Preserve any unknown field in the header */
966 if (s
->unknown_header_fields_size
) {
967 if (buflen
< s
->unknown_header_fields_size
) {
972 memcpy(buf
, s
->unknown_header_fields
, s
->unknown_header_fields_size
);
973 buf
+= s
->unknown_header_fields_size
;
974 buflen
-= s
->unknown_header_fields_size
;
977 /* Backing file format header extension */
978 if (*bs
->backing_format
) {
979 ret
= header_ext_add(buf
, QCOW2_EXT_MAGIC_BACKING_FORMAT
,
980 bs
->backing_format
, strlen(bs
->backing_format
),
991 Qcow2Feature features
[] = {
993 .type
= QCOW2_FEAT_TYPE_INCOMPATIBLE
,
994 .bit
= QCOW2_INCOMPAT_DIRTY_BITNR
,
999 ret
= header_ext_add(buf
, QCOW2_EXT_MAGIC_FEATURE_TABLE
,
1000 features
, sizeof(features
), buflen
);
1007 /* Keep unknown header extensions */
1008 QLIST_FOREACH(uext
, &s
->unknown_header_ext
, next
) {
1009 ret
= header_ext_add(buf
, uext
->magic
, uext
->data
, uext
->len
, buflen
);
1018 /* End of header extensions */
1019 ret
= header_ext_add(buf
, QCOW2_EXT_MAGIC_END
, NULL
, 0, buflen
);
1027 /* Backing file name */
1028 if (*bs
->backing_file
) {
1029 size_t backing_file_len
= strlen(bs
->backing_file
);
1031 if (buflen
< backing_file_len
) {
1036 strncpy(buf
, bs
->backing_file
, buflen
);
1038 header
->backing_file_offset
= cpu_to_be64(buf
- ((char*) header
));
1039 header
->backing_file_size
= cpu_to_be32(backing_file_len
);
1042 /* Write the new header */
1043 ret
= bdrv_pwrite(bs
->file
, 0, header
, s
->cluster_size
);
1054 static int qcow2_change_backing_file(BlockDriverState
*bs
,
1055 const char *backing_file
, const char *backing_fmt
)
1057 pstrcpy(bs
->backing_file
, sizeof(bs
->backing_file
), backing_file
?: "");
1058 pstrcpy(bs
->backing_format
, sizeof(bs
->backing_format
), backing_fmt
?: "");
1060 return qcow2_update_header(bs
);
1063 static int preallocate(BlockDriverState
*bs
)
1065 uint64_t nb_sectors
;
1071 nb_sectors
= bdrv_getlength(bs
) >> 9;
1073 qemu_co_queue_init(&meta
.dependent_requests
);
1074 meta
.cluster_offset
= 0;
1076 while (nb_sectors
) {
1077 num
= MIN(nb_sectors
, INT_MAX
>> 9);
1078 ret
= qcow2_alloc_cluster_offset(bs
, offset
, 0, num
, &num
, &meta
);
1083 ret
= qcow2_alloc_cluster_link_l2(bs
, &meta
);
1085 qcow2_free_any_clusters(bs
, meta
.cluster_offset
, meta
.nb_clusters
);
1089 /* There are no dependent requests, but we need to remove our request
1090 * from the list of in-flight requests */
1091 run_dependent_requests(bs
->opaque
, &meta
);
1093 /* TODO Preallocate data if requested */
1100 * It is expected that the image file is large enough to actually contain
1101 * all of the allocated clusters (otherwise we get failing reads after
1102 * EOF). Extend the image to the last allocated sector.
1104 if (meta
.cluster_offset
!= 0) {
1106 memset(buf
, 0, 512);
1107 ret
= bdrv_write(bs
->file
, (meta
.cluster_offset
>> 9) + num
- 1, buf
, 1);
1116 static int qcow2_create2(const char *filename
, int64_t total_size
,
1117 const char *backing_file
, const char *backing_format
,
1118 int flags
, size_t cluster_size
, int prealloc
,
1119 QEMUOptionParameter
*options
, int version
)
1121 /* Calculate cluster_bits */
1123 cluster_bits
= ffs(cluster_size
) - 1;
1124 if (cluster_bits
< MIN_CLUSTER_BITS
|| cluster_bits
> MAX_CLUSTER_BITS
||
1125 (1 << cluster_bits
) != cluster_size
)
1128 "Cluster size must be a power of two between %d and %dk",
1129 1 << MIN_CLUSTER_BITS
, 1 << (MAX_CLUSTER_BITS
- 10));
1134 * Open the image file and write a minimal qcow2 header.
1136 * We keep things simple and start with a zero-sized image. We also
1137 * do without refcount blocks or a L1 table for now. We'll fix the
1138 * inconsistency later.
1140 * We do need a refcount table because growing the refcount table means
1141 * allocating two new refcount blocks - the seconds of which would be at
1142 * 2 GB for 64k clusters, and we don't want to have a 2 GB initial file
1143 * size for any qcow2 image.
1145 BlockDriverState
* bs
;
1147 uint8_t* refcount_table
;
1150 ret
= bdrv_create_file(filename
, options
);
1155 ret
= bdrv_file_open(&bs
, filename
, BDRV_O_RDWR
);
1160 /* Write the header */
1161 memset(&header
, 0, sizeof(header
));
1162 header
.magic
= cpu_to_be32(QCOW_MAGIC
);
1163 header
.version
= cpu_to_be32(version
);
1164 header
.cluster_bits
= cpu_to_be32(cluster_bits
);
1165 header
.size
= cpu_to_be64(0);
1166 header
.l1_table_offset
= cpu_to_be64(0);
1167 header
.l1_size
= cpu_to_be32(0);
1168 header
.refcount_table_offset
= cpu_to_be64(cluster_size
);
1169 header
.refcount_table_clusters
= cpu_to_be32(1);
1170 header
.refcount_order
= cpu_to_be32(3 + REFCOUNT_SHIFT
);
1171 header
.header_length
= cpu_to_be32(sizeof(header
));
1173 if (flags
& BLOCK_FLAG_ENCRYPT
) {
1174 header
.crypt_method
= cpu_to_be32(QCOW_CRYPT_AES
);
1176 header
.crypt_method
= cpu_to_be32(QCOW_CRYPT_NONE
);
1179 ret
= bdrv_pwrite(bs
, 0, &header
, sizeof(header
));
1184 /* Write an empty refcount table */
1185 refcount_table
= g_malloc0(cluster_size
);
1186 ret
= bdrv_pwrite(bs
, cluster_size
, refcount_table
, cluster_size
);
1187 g_free(refcount_table
);
1196 * And now open the image and make it consistent first (i.e. increase the
1197 * refcount of the cluster that is occupied by the header and the refcount
1200 BlockDriver
* drv
= bdrv_find_format("qcow2");
1201 assert(drv
!= NULL
);
1202 ret
= bdrv_open(bs
, filename
,
1203 BDRV_O_RDWR
| BDRV_O_CACHE_WB
| BDRV_O_NO_FLUSH
, drv
);
1208 ret
= qcow2_alloc_clusters(bs
, 2 * cluster_size
);
1212 } else if (ret
!= 0) {
1213 error_report("Huh, first cluster in empty image is already in use?");
1217 /* Okay, now that we have a valid image, let's give it the right size */
1218 ret
= bdrv_truncate(bs
, total_size
* BDRV_SECTOR_SIZE
);
1223 /* Want a backing file? There you go.*/
1225 ret
= bdrv_change_backing_file(bs
, backing_file
, backing_format
);
1231 /* And if we're supposed to preallocate metadata, do that now */
1233 BDRVQcowState
*s
= bs
->opaque
;
1234 qemu_co_mutex_lock(&s
->lock
);
1235 ret
= preallocate(bs
);
1236 qemu_co_mutex_unlock(&s
->lock
);
1248 static int qcow2_create(const char *filename
, QEMUOptionParameter
*options
)
1250 const char *backing_file
= NULL
;
1251 const char *backing_fmt
= NULL
;
1252 uint64_t sectors
= 0;
1254 size_t cluster_size
= DEFAULT_CLUSTER_SIZE
;
1258 /* Read out options */
1259 while (options
&& options
->name
) {
1260 if (!strcmp(options
->name
, BLOCK_OPT_SIZE
)) {
1261 sectors
= options
->value
.n
/ 512;
1262 } else if (!strcmp(options
->name
, BLOCK_OPT_BACKING_FILE
)) {
1263 backing_file
= options
->value
.s
;
1264 } else if (!strcmp(options
->name
, BLOCK_OPT_BACKING_FMT
)) {
1265 backing_fmt
= options
->value
.s
;
1266 } else if (!strcmp(options
->name
, BLOCK_OPT_ENCRYPT
)) {
1267 flags
|= options
->value
.n
? BLOCK_FLAG_ENCRYPT
: 0;
1268 } else if (!strcmp(options
->name
, BLOCK_OPT_CLUSTER_SIZE
)) {
1269 if (options
->value
.n
) {
1270 cluster_size
= options
->value
.n
;
1272 } else if (!strcmp(options
->name
, BLOCK_OPT_PREALLOC
)) {
1273 if (!options
->value
.s
|| !strcmp(options
->value
.s
, "off")) {
1275 } else if (!strcmp(options
->value
.s
, "metadata")) {
1278 fprintf(stderr
, "Invalid preallocation mode: '%s'\n",
1282 } else if (!strcmp(options
->name
, BLOCK_OPT_COMPAT_LEVEL
)) {
1283 if (!options
->value
.s
|| !strcmp(options
->value
.s
, "0.10")) {
1285 } else if (!strcmp(options
->value
.s
, "1.1")) {
1288 fprintf(stderr
, "Invalid compatibility level: '%s'\n",
1296 if (backing_file
&& prealloc
) {
1297 fprintf(stderr
, "Backing file and preallocation cannot be used at "
1302 return qcow2_create2(filename
, sectors
, backing_file
, backing_fmt
, flags
,
1303 cluster_size
, prealloc
, options
, version
);
1306 static int qcow2_make_empty(BlockDriverState
*bs
)
1309 /* XXX: not correct */
1310 BDRVQcowState
*s
= bs
->opaque
;
1311 uint32_t l1_length
= s
->l1_size
* sizeof(uint64_t);
1314 memset(s
->l1_table
, 0, l1_length
);
1315 if (bdrv_pwrite(bs
->file
, s
->l1_table_offset
, s
->l1_table
, l1_length
) < 0)
1317 ret
= bdrv_truncate(bs
->file
, s
->l1_table_offset
+ l1_length
);
1326 static coroutine_fn
int qcow2_co_write_zeroes(BlockDriverState
*bs
,
1327 int64_t sector_num
, int nb_sectors
)
1330 BDRVQcowState
*s
= bs
->opaque
;
1332 /* Emulate misaligned zero writes */
1333 if (sector_num
% s
->cluster_sectors
|| nb_sectors
% s
->cluster_sectors
) {
1337 /* Whatever is left can use real zero clusters */
1338 qemu_co_mutex_lock(&s
->lock
);
1339 ret
= qcow2_zero_clusters(bs
, sector_num
<< BDRV_SECTOR_BITS
,
1341 qemu_co_mutex_unlock(&s
->lock
);
1346 static coroutine_fn
int qcow2_co_discard(BlockDriverState
*bs
,
1347 int64_t sector_num
, int nb_sectors
)
1350 BDRVQcowState
*s
= bs
->opaque
;
1352 qemu_co_mutex_lock(&s
->lock
);
1353 ret
= qcow2_discard_clusters(bs
, sector_num
<< BDRV_SECTOR_BITS
,
1355 qemu_co_mutex_unlock(&s
->lock
);
1359 static int qcow2_truncate(BlockDriverState
*bs
, int64_t offset
)
1361 BDRVQcowState
*s
= bs
->opaque
;
1362 int ret
, new_l1_size
;
1365 error_report("The new size must be a multiple of 512");
1369 /* cannot proceed if image has snapshots */
1370 if (s
->nb_snapshots
) {
1371 error_report("Can't resize an image which has snapshots");
1375 /* shrinking is currently not supported */
1376 if (offset
< bs
->total_sectors
* 512) {
1377 error_report("qcow2 doesn't support shrinking images yet");
1381 new_l1_size
= size_to_l1(s
, offset
);
1382 ret
= qcow2_grow_l1_table(bs
, new_l1_size
, true);
1387 /* write updated header.size */
1388 offset
= cpu_to_be64(offset
);
1389 ret
= bdrv_pwrite_sync(bs
->file
, offsetof(QCowHeader
, size
),
1390 &offset
, sizeof(uint64_t));
1395 s
->l1_vm_state_index
= new_l1_size
;
1399 /* XXX: put compressed sectors first, then all the cluster aligned
1400 tables to avoid losing bytes in alignment */
1401 static int qcow2_write_compressed(BlockDriverState
*bs
, int64_t sector_num
,
1402 const uint8_t *buf
, int nb_sectors
)
1404 BDRVQcowState
*s
= bs
->opaque
;
1408 uint64_t cluster_offset
;
1410 if (nb_sectors
== 0) {
1411 /* align end of file to a sector boundary to ease reading with
1412 sector based I/Os */
1413 cluster_offset
= bdrv_getlength(bs
->file
);
1414 cluster_offset
= (cluster_offset
+ 511) & ~511;
1415 bdrv_truncate(bs
->file
, cluster_offset
);
1419 if (nb_sectors
!= s
->cluster_sectors
)
1422 out_buf
= g_malloc(s
->cluster_size
+ (s
->cluster_size
/ 1000) + 128);
1424 /* best compression, small window, no zlib header */
1425 memset(&strm
, 0, sizeof(strm
));
1426 ret
= deflateInit2(&strm
, Z_DEFAULT_COMPRESSION
,
1428 9, Z_DEFAULT_STRATEGY
);
1434 strm
.avail_in
= s
->cluster_size
;
1435 strm
.next_in
= (uint8_t *)buf
;
1436 strm
.avail_out
= s
->cluster_size
;
1437 strm
.next_out
= out_buf
;
1439 ret
= deflate(&strm
, Z_FINISH
);
1440 if (ret
!= Z_STREAM_END
&& ret
!= Z_OK
) {
1445 out_len
= strm
.next_out
- out_buf
;
1449 if (ret
!= Z_STREAM_END
|| out_len
>= s
->cluster_size
) {
1450 /* could not compress: write normal cluster */
1451 ret
= bdrv_write(bs
, sector_num
, buf
, s
->cluster_sectors
);
1456 cluster_offset
= qcow2_alloc_compressed_cluster_offset(bs
,
1457 sector_num
<< 9, out_len
);
1458 if (!cluster_offset
) {
1462 cluster_offset
&= s
->cluster_offset_mask
;
1463 BLKDBG_EVENT(bs
->file
, BLKDBG_WRITE_COMPRESSED
);
1464 ret
= bdrv_pwrite(bs
->file
, cluster_offset
, out_buf
, out_len
);
1476 static coroutine_fn
int qcow2_co_flush_to_os(BlockDriverState
*bs
)
1478 BDRVQcowState
*s
= bs
->opaque
;
1481 qemu_co_mutex_lock(&s
->lock
);
1482 ret
= qcow2_cache_flush(bs
, s
->l2_table_cache
);
1484 qemu_co_mutex_unlock(&s
->lock
);
1488 ret
= qcow2_cache_flush(bs
, s
->refcount_block_cache
);
1490 qemu_co_mutex_unlock(&s
->lock
);
1493 qemu_co_mutex_unlock(&s
->lock
);
1498 static int64_t qcow2_vm_state_offset(BDRVQcowState
*s
)
1500 return (int64_t)s
->l1_vm_state_index
<< (s
->cluster_bits
+ s
->l2_bits
);
1503 static int qcow2_get_info(BlockDriverState
*bs
, BlockDriverInfo
*bdi
)
1505 BDRVQcowState
*s
= bs
->opaque
;
1506 bdi
->cluster_size
= s
->cluster_size
;
1507 bdi
->vm_state_offset
= qcow2_vm_state_offset(s
);
1512 static int qcow2_check(BlockDriverState
*bs
, BdrvCheckResult
*result
,
1515 return qcow2_check_refcounts(bs
, result
, fix
);
1519 static void dump_refcounts(BlockDriverState
*bs
)
1521 BDRVQcowState
*s
= bs
->opaque
;
1522 int64_t nb_clusters
, k
, k1
, size
;
1525 size
= bdrv_getlength(bs
->file
);
1526 nb_clusters
= size_to_clusters(s
, size
);
1527 for(k
= 0; k
< nb_clusters
;) {
1529 refcount
= get_refcount(bs
, k
);
1531 while (k
< nb_clusters
&& get_refcount(bs
, k
) == refcount
)
1533 printf("%" PRId64
": refcount=%d nb=%" PRId64
"\n", k
, refcount
,
1539 static int qcow2_save_vmstate(BlockDriverState
*bs
, const uint8_t *buf
,
1540 int64_t pos
, int size
)
1542 BDRVQcowState
*s
= bs
->opaque
;
1543 int growable
= bs
->growable
;
1546 BLKDBG_EVENT(bs
->file
, BLKDBG_VMSTATE_SAVE
);
1548 ret
= bdrv_pwrite(bs
, qcow2_vm_state_offset(s
) + pos
, buf
, size
);
1549 bs
->growable
= growable
;
1554 static int qcow2_load_vmstate(BlockDriverState
*bs
, uint8_t *buf
,
1555 int64_t pos
, int size
)
1557 BDRVQcowState
*s
= bs
->opaque
;
1558 int growable
= bs
->growable
;
1561 BLKDBG_EVENT(bs
->file
, BLKDBG_VMSTATE_LOAD
);
1563 ret
= bdrv_pread(bs
, qcow2_vm_state_offset(s
) + pos
, buf
, size
);
1564 bs
->growable
= growable
;
1569 static QEMUOptionParameter qcow2_create_options
[] = {
1571 .name
= BLOCK_OPT_SIZE
,
1573 .help
= "Virtual disk size"
1576 .name
= BLOCK_OPT_COMPAT_LEVEL
,
1578 .help
= "Compatibility level (0.10 or 1.1)"
1581 .name
= BLOCK_OPT_BACKING_FILE
,
1583 .help
= "File name of a base image"
1586 .name
= BLOCK_OPT_BACKING_FMT
,
1588 .help
= "Image format of the base image"
1591 .name
= BLOCK_OPT_ENCRYPT
,
1593 .help
= "Encrypt the image"
1596 .name
= BLOCK_OPT_CLUSTER_SIZE
,
1598 .help
= "qcow2 cluster size",
1599 .value
= { .n
= DEFAULT_CLUSTER_SIZE
},
1602 .name
= BLOCK_OPT_PREALLOC
,
1604 .help
= "Preallocation mode (allowed values: off, metadata)"
1609 static BlockDriver bdrv_qcow2
= {
1610 .format_name
= "qcow2",
1611 .instance_size
= sizeof(BDRVQcowState
),
1612 .bdrv_probe
= qcow2_probe
,
1613 .bdrv_open
= qcow2_open
,
1614 .bdrv_close
= qcow2_close
,
1615 .bdrv_create
= qcow2_create
,
1616 .bdrv_co_is_allocated
= qcow2_co_is_allocated
,
1617 .bdrv_set_key
= qcow2_set_key
,
1618 .bdrv_make_empty
= qcow2_make_empty
,
1620 .bdrv_co_readv
= qcow2_co_readv
,
1621 .bdrv_co_writev
= qcow2_co_writev
,
1622 .bdrv_co_flush_to_os
= qcow2_co_flush_to_os
,
1624 .bdrv_co_write_zeroes
= qcow2_co_write_zeroes
,
1625 .bdrv_co_discard
= qcow2_co_discard
,
1626 .bdrv_truncate
= qcow2_truncate
,
1627 .bdrv_write_compressed
= qcow2_write_compressed
,
1629 .bdrv_snapshot_create
= qcow2_snapshot_create
,
1630 .bdrv_snapshot_goto
= qcow2_snapshot_goto
,
1631 .bdrv_snapshot_delete
= qcow2_snapshot_delete
,
1632 .bdrv_snapshot_list
= qcow2_snapshot_list
,
1633 .bdrv_snapshot_load_tmp
= qcow2_snapshot_load_tmp
,
1634 .bdrv_get_info
= qcow2_get_info
,
1636 .bdrv_save_vmstate
= qcow2_save_vmstate
,
1637 .bdrv_load_vmstate
= qcow2_load_vmstate
,
1639 .bdrv_change_backing_file
= qcow2_change_backing_file
,
1641 .bdrv_invalidate_cache
= qcow2_invalidate_cache
,
1643 .create_options
= qcow2_create_options
,
1644 .bdrv_check
= qcow2_check
,
1647 static void bdrv_qcow2_init(void)
1649 bdrv_register(&bdrv_qcow2
);
1652 block_init(bdrv_qcow2_init
);