2 * Block driver for the Virtual Disk Image (VDI) format
4 * Copyright (c) 2009, 2012 Stefan Weil
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 2 of the License, or
9 * (at your option) version 3 or any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 * http://forums.virtualbox.org/viewtopic.php?t=8046
22 * This driver supports create / read / write operations on VDI images.
24 * Todo (see also TODO in code):
26 * Some features like snapshots are still missing.
28 * Deallocation of zero-filled blocks and shrinking images are missing, too
29 * (might be added to common block layer).
31 * Allocation of blocks could be optimized (less writes to block map and
34 * Read and write of adjacent blocks could be done in one operation
35 * (current code uses one operation per block (1 MiB).
37 * The code is not thread safe (missing locks for changes in header and
38 * block table, no problem with current QEMU).
42 * Blocks (VDI documentation) correspond to clusters (QEMU).
43 * QEMU's backing files could be implemented using VDI snapshot files (TODO).
44 * VDI snapshot files may also contain the complete machine state.
45 * Maybe this machine state can be converted to QEMU PC machine snapshot data.
47 * The driver keeps a block cache (little endian entries) in memory.
48 * For the standard block size (1 MiB), a 1 TiB disk will use 4 MiB RAM,
49 * so this seems to be reasonable.
52 #include "qemu/osdep.h"
53 #include "qapi/error.h"
54 #include "block/block_int.h"
55 #include "sysemu/block-backend.h"
56 #include "qemu/module.h"
57 #include "qemu/bswap.h"
58 #include "migration/migration.h"
59 #include "qemu/coroutine.h"
60 #include "qemu/cutils.h"
61 #include "qemu/uuid.h"
63 /* Code configuration options. */
65 /* Enable debug messages. */
66 //~ #define CONFIG_VDI_DEBUG
68 /* Support write operations on VDI images. */
69 #define CONFIG_VDI_WRITE
71 /* Support non-standard block (cluster) size. This is untested.
72 * Maybe it will be needed for very large images.
74 //~ #define CONFIG_VDI_BLOCK_SIZE
76 /* Support static (fixed, pre-allocated) images. */
77 #define CONFIG_VDI_STATIC_IMAGE
79 /* Command line option for static images. */
80 #define BLOCK_OPT_STATIC "static"
83 #define MiB (KiB * KiB)
85 #define SECTOR_SIZE 512
86 #define DEFAULT_CLUSTER_SIZE (1 * MiB)
88 #if defined(CONFIG_VDI_DEBUG)
89 #define logout(fmt, ...) \
90 fprintf(stderr, "vdi\t%-24s" fmt, __func__, ##__VA_ARGS__)
92 #define logout(fmt, ...) ((void)0)
95 /* Image signature. */
96 #define VDI_SIGNATURE 0xbeda107f
99 #define VDI_VERSION_1_1 0x00010001
102 #define VDI_TYPE_DYNAMIC 1
103 #define VDI_TYPE_STATIC 2
105 /* Innotek / SUN images use these strings in header.text:
106 * "<<< innotek VirtualBox Disk Image >>>\n"
107 * "<<< Sun xVM VirtualBox Disk Image >>>\n"
108 * "<<< Sun VirtualBox Disk Image >>>\n"
109 * The value does not matter, so QEMU created images use a different text.
111 #define VDI_TEXT "<<< QEMU VM Virtual Disk Image >>>\n"
113 /* A never-allocated block; semantically arbitrary content. */
114 #define VDI_UNALLOCATED 0xffffffffU
116 /* A discarded (no longer allocated) block; semantically zero-filled. */
117 #define VDI_DISCARDED 0xfffffffeU
119 #define VDI_IS_ALLOCATED(X) ((X) < VDI_DISCARDED)
121 /* The bmap will take up VDI_BLOCKS_IN_IMAGE_MAX * sizeof(uint32_t) bytes; since
122 * the bmap is read and written in a single operation, its size needs to be
123 * limited to INT_MAX; furthermore, when opening an image, the bmap size is
124 * rounded up to be aligned on BDRV_SECTOR_SIZE.
125 * Therefore this should satisfy the following:
126 * VDI_BLOCKS_IN_IMAGE_MAX * sizeof(uint32_t) + BDRV_SECTOR_SIZE == INT_MAX + 1
127 * (INT_MAX + 1 is the first value not representable as an int)
128 * This guarantees that any value below or equal to the constant will, when
129 * multiplied by sizeof(uint32_t) and rounded up to a BDRV_SECTOR_SIZE boundary,
130 * still be below or equal to INT_MAX. */
131 #define VDI_BLOCKS_IN_IMAGE_MAX \
132 ((unsigned)((INT_MAX + 1u - BDRV_SECTOR_SIZE) / sizeof(uint32_t)))
133 #define VDI_DISK_SIZE_MAX ((uint64_t)VDI_BLOCKS_IN_IMAGE_MAX * \
134 (uint64_t)DEFAULT_CLUSTER_SIZE)
140 uint32_t header_size
;
142 uint32_t image_flags
;
143 char description
[256];
144 uint32_t offset_bmap
;
145 uint32_t offset_data
;
146 uint32_t cylinders
; /* disk geometry, unused here */
147 uint32_t heads
; /* disk geometry, unused here */
148 uint32_t sectors
; /* disk geometry, unused here */
149 uint32_t sector_size
;
153 uint32_t block_extra
; /* unused here */
154 uint32_t blocks_in_image
;
155 uint32_t blocks_allocated
;
157 QemuUUID uuid_last_snap
;
159 QemuUUID uuid_parent
;
161 } QEMU_PACKED VdiHeader
;
164 /* The block map entries are little endian (even in memory). */
166 /* Size of block (bytes). */
168 /* Size of block (sectors). */
169 uint32_t block_sectors
;
170 /* First sector of block map. */
171 uint32_t bmap_sector
;
172 /* VDI header (converted to host endianness). */
177 Error
*migration_blocker
;
180 static void vdi_header_to_cpu(VdiHeader
*header
)
182 le32_to_cpus(&header
->signature
);
183 le32_to_cpus(&header
->version
);
184 le32_to_cpus(&header
->header_size
);
185 le32_to_cpus(&header
->image_type
);
186 le32_to_cpus(&header
->image_flags
);
187 le32_to_cpus(&header
->offset_bmap
);
188 le32_to_cpus(&header
->offset_data
);
189 le32_to_cpus(&header
->cylinders
);
190 le32_to_cpus(&header
->heads
);
191 le32_to_cpus(&header
->sectors
);
192 le32_to_cpus(&header
->sector_size
);
193 le64_to_cpus(&header
->disk_size
);
194 le32_to_cpus(&header
->block_size
);
195 le32_to_cpus(&header
->block_extra
);
196 le32_to_cpus(&header
->blocks_in_image
);
197 le32_to_cpus(&header
->blocks_allocated
);
198 qemu_uuid_bswap(&header
->uuid_image
);
199 qemu_uuid_bswap(&header
->uuid_last_snap
);
200 qemu_uuid_bswap(&header
->uuid_link
);
201 qemu_uuid_bswap(&header
->uuid_parent
);
204 static void vdi_header_to_le(VdiHeader
*header
)
206 cpu_to_le32s(&header
->signature
);
207 cpu_to_le32s(&header
->version
);
208 cpu_to_le32s(&header
->header_size
);
209 cpu_to_le32s(&header
->image_type
);
210 cpu_to_le32s(&header
->image_flags
);
211 cpu_to_le32s(&header
->offset_bmap
);
212 cpu_to_le32s(&header
->offset_data
);
213 cpu_to_le32s(&header
->cylinders
);
214 cpu_to_le32s(&header
->heads
);
215 cpu_to_le32s(&header
->sectors
);
216 cpu_to_le32s(&header
->sector_size
);
217 cpu_to_le64s(&header
->disk_size
);
218 cpu_to_le32s(&header
->block_size
);
219 cpu_to_le32s(&header
->block_extra
);
220 cpu_to_le32s(&header
->blocks_in_image
);
221 cpu_to_le32s(&header
->blocks_allocated
);
222 qemu_uuid_bswap(&header
->uuid_image
);
223 qemu_uuid_bswap(&header
->uuid_last_snap
);
224 qemu_uuid_bswap(&header
->uuid_link
);
225 qemu_uuid_bswap(&header
->uuid_parent
);
228 #if defined(CONFIG_VDI_DEBUG)
229 static void vdi_header_print(VdiHeader
*header
)
232 logout("text %s", header
->text
);
233 logout("signature 0x%08x\n", header
->signature
);
234 logout("header size 0x%04x\n", header
->header_size
);
235 logout("image type 0x%04x\n", header
->image_type
);
236 logout("image flags 0x%04x\n", header
->image_flags
);
237 logout("description %s\n", header
->description
);
238 logout("offset bmap 0x%04x\n", header
->offset_bmap
);
239 logout("offset data 0x%04x\n", header
->offset_data
);
240 logout("cylinders 0x%04x\n", header
->cylinders
);
241 logout("heads 0x%04x\n", header
->heads
);
242 logout("sectors 0x%04x\n", header
->sectors
);
243 logout("sector size 0x%04x\n", header
->sector_size
);
244 logout("image size 0x%" PRIx64
" B (%" PRIu64
" MiB)\n",
245 header
->disk_size
, header
->disk_size
/ MiB
);
246 logout("block size 0x%04x\n", header
->block_size
);
247 logout("block extra 0x%04x\n", header
->block_extra
);
248 logout("blocks tot. 0x%04x\n", header
->blocks_in_image
);
249 logout("blocks all. 0x%04x\n", header
->blocks_allocated
);
250 uuid_unparse(header
->uuid_image
, uuid
);
251 logout("uuid image %s\n", uuid
);
252 uuid_unparse(header
->uuid_last_snap
, uuid
);
253 logout("uuid snap %s\n", uuid
);
254 uuid_unparse(header
->uuid_link
, uuid
);
255 logout("uuid link %s\n", uuid
);
256 uuid_unparse(header
->uuid_parent
, uuid
);
257 logout("uuid parent %s\n", uuid
);
261 static int vdi_check(BlockDriverState
*bs
, BdrvCheckResult
*res
,
264 /* TODO: additional checks possible. */
265 BDRVVdiState
*s
= (BDRVVdiState
*)bs
->opaque
;
266 uint32_t blocks_allocated
= 0;
275 bmap
= g_try_new(uint32_t, s
->header
.blocks_in_image
);
276 if (s
->header
.blocks_in_image
&& bmap
== NULL
) {
281 memset(bmap
, 0xff, s
->header
.blocks_in_image
* sizeof(uint32_t));
283 /* Check block map and value of blocks_allocated. */
284 for (block
= 0; block
< s
->header
.blocks_in_image
; block
++) {
285 uint32_t bmap_entry
= le32_to_cpu(s
->bmap
[block
]);
286 if (VDI_IS_ALLOCATED(bmap_entry
)) {
287 if (bmap_entry
< s
->header
.blocks_in_image
) {
289 if (!VDI_IS_ALLOCATED(bmap
[bmap_entry
])) {
290 bmap
[bmap_entry
] = bmap_entry
;
292 fprintf(stderr
, "ERROR: block index %" PRIu32
293 " also used by %" PRIu32
"\n", bmap
[bmap_entry
], bmap_entry
);
297 fprintf(stderr
, "ERROR: block index %" PRIu32
298 " too large, is %" PRIu32
"\n", block
, bmap_entry
);
303 if (blocks_allocated
!= s
->header
.blocks_allocated
) {
304 fprintf(stderr
, "ERROR: allocated blocks mismatch, is %" PRIu32
305 ", should be %" PRIu32
"\n",
306 blocks_allocated
, s
->header
.blocks_allocated
);
315 static int vdi_get_info(BlockDriverState
*bs
, BlockDriverInfo
*bdi
)
317 /* TODO: vdi_get_info would be needed for machine snapshots.
318 vm_state_offset is still missing. */
319 BDRVVdiState
*s
= (BDRVVdiState
*)bs
->opaque
;
321 bdi
->cluster_size
= s
->block_size
;
322 bdi
->vm_state_offset
= 0;
323 bdi
->unallocated_blocks_are_zero
= true;
327 static int vdi_make_empty(BlockDriverState
*bs
)
329 /* TODO: missing code. */
331 /* The return value for missing code must be 0, see block.c. */
335 static int vdi_probe(const uint8_t *buf
, int buf_size
, const char *filename
)
337 const VdiHeader
*header
= (const VdiHeader
*)buf
;
342 if (buf_size
< sizeof(*header
)) {
343 /* Header too small, no VDI. */
344 } else if (le32_to_cpu(header
->signature
) == VDI_SIGNATURE
) {
349 logout("no vdi image\n");
351 logout("%s", header
->text
);
357 static int vdi_open(BlockDriverState
*bs
, QDict
*options
, int flags
,
360 BDRVVdiState
*s
= bs
->opaque
;
364 Error
*local_err
= NULL
;
368 ret
= bdrv_read(bs
->file
, 0, (uint8_t *)&header
, 1);
373 vdi_header_to_cpu(&header
);
374 #if defined(CONFIG_VDI_DEBUG)
375 vdi_header_print(&header
);
378 if (header
.disk_size
> VDI_DISK_SIZE_MAX
) {
379 error_setg(errp
, "Unsupported VDI image size (size is 0x%" PRIx64
380 ", max supported is 0x%" PRIx64
")",
381 header
.disk_size
, VDI_DISK_SIZE_MAX
);
386 if (header
.disk_size
% SECTOR_SIZE
!= 0) {
387 /* 'VBoxManage convertfromraw' can create images with odd disk sizes.
388 We accept them but round the disk size to the next multiple of
390 logout("odd disk size %" PRIu64
" B, round up\n", header
.disk_size
);
391 header
.disk_size
= ROUND_UP(header
.disk_size
, SECTOR_SIZE
);
394 if (header
.signature
!= VDI_SIGNATURE
) {
395 error_setg(errp
, "Image not in VDI format (bad signature %08" PRIx32
396 ")", header
.signature
);
399 } else if (header
.version
!= VDI_VERSION_1_1
) {
400 error_setg(errp
, "unsupported VDI image (version %" PRIu32
".%" PRIu32
401 ")", header
.version
>> 16, header
.version
& 0xffff);
404 } else if (header
.offset_bmap
% SECTOR_SIZE
!= 0) {
405 /* We only support block maps which start on a sector boundary. */
406 error_setg(errp
, "unsupported VDI image (unaligned block map offset "
407 "0x%" PRIx32
")", header
.offset_bmap
);
410 } else if (header
.offset_data
% SECTOR_SIZE
!= 0) {
411 /* We only support data blocks which start on a sector boundary. */
412 error_setg(errp
, "unsupported VDI image (unaligned data offset 0x%"
413 PRIx32
")", header
.offset_data
);
416 } else if (header
.sector_size
!= SECTOR_SIZE
) {
417 error_setg(errp
, "unsupported VDI image (sector size %" PRIu32
418 " is not %u)", header
.sector_size
, SECTOR_SIZE
);
421 } else if (header
.block_size
!= DEFAULT_CLUSTER_SIZE
) {
422 error_setg(errp
, "unsupported VDI image (block size %" PRIu32
423 " is not %u)", header
.block_size
, DEFAULT_CLUSTER_SIZE
);
426 } else if (header
.disk_size
>
427 (uint64_t)header
.blocks_in_image
* header
.block_size
) {
428 error_setg(errp
, "unsupported VDI image (disk size %" PRIu64
", "
429 "image bitmap has room for %" PRIu64
")",
431 (uint64_t)header
.blocks_in_image
* header
.block_size
);
434 } else if (!qemu_uuid_is_null(&header
.uuid_link
)) {
435 error_setg(errp
, "unsupported VDI image (non-NULL link UUID)");
438 } else if (!qemu_uuid_is_null(&header
.uuid_parent
)) {
439 error_setg(errp
, "unsupported VDI image (non-NULL parent UUID)");
442 } else if (header
.blocks_in_image
> VDI_BLOCKS_IN_IMAGE_MAX
) {
443 error_setg(errp
, "unsupported VDI image "
444 "(too many blocks %u, max is %u)",
445 header
.blocks_in_image
, VDI_BLOCKS_IN_IMAGE_MAX
);
450 bs
->total_sectors
= header
.disk_size
/ SECTOR_SIZE
;
452 s
->block_size
= header
.block_size
;
453 s
->block_sectors
= header
.block_size
/ SECTOR_SIZE
;
454 s
->bmap_sector
= header
.offset_bmap
/ SECTOR_SIZE
;
457 bmap_size
= header
.blocks_in_image
* sizeof(uint32_t);
458 bmap_size
= DIV_ROUND_UP(bmap_size
, SECTOR_SIZE
);
459 s
->bmap
= qemu_try_blockalign(bs
->file
->bs
, bmap_size
* SECTOR_SIZE
);
460 if (s
->bmap
== NULL
) {
465 ret
= bdrv_read(bs
->file
, s
->bmap_sector
, (uint8_t *)s
->bmap
,
471 /* Disable migration when vdi images are used */
472 error_setg(&s
->migration_blocker
, "The vdi format used by node '%s' "
473 "does not support live migration",
474 bdrv_get_device_or_node_name(bs
));
475 ret
= migrate_add_blocker(s
->migration_blocker
, &local_err
);
477 error_propagate(errp
, local_err
);
478 error_free(s
->migration_blocker
);
482 qemu_co_mutex_init(&s
->write_lock
);
493 static int vdi_reopen_prepare(BDRVReopenState
*state
,
494 BlockReopenQueue
*queue
, Error
**errp
)
499 static int64_t coroutine_fn
vdi_co_get_block_status(BlockDriverState
*bs
,
500 int64_t sector_num
, int nb_sectors
, int *pnum
, BlockDriverState
**file
)
502 /* TODO: Check for too large sector_num (in bdrv_is_allocated or here). */
503 BDRVVdiState
*s
= (BDRVVdiState
*)bs
->opaque
;
504 size_t bmap_index
= sector_num
/ s
->block_sectors
;
505 size_t sector_in_block
= sector_num
% s
->block_sectors
;
506 int n_sectors
= s
->block_sectors
- sector_in_block
;
507 uint32_t bmap_entry
= le32_to_cpu(s
->bmap
[bmap_index
]);
511 logout("%p, %" PRId64
", %d, %p\n", bs
, sector_num
, nb_sectors
, pnum
);
512 if (n_sectors
> nb_sectors
) {
513 n_sectors
= nb_sectors
;
516 result
= VDI_IS_ALLOCATED(bmap_entry
);
521 offset
= s
->header
.offset_data
+
522 (uint64_t)bmap_entry
* s
->block_size
+
523 sector_in_block
* SECTOR_SIZE
;
524 *file
= bs
->file
->bs
;
525 return BDRV_BLOCK_DATA
| BDRV_BLOCK_OFFSET_VALID
| offset
;
528 static int coroutine_fn
529 vdi_co_preadv(BlockDriverState
*bs
, uint64_t offset
, uint64_t bytes
,
530 QEMUIOVector
*qiov
, int flags
)
532 BDRVVdiState
*s
= bs
->opaque
;
533 QEMUIOVector local_qiov
;
535 uint32_t block_index
;
536 uint32_t offset_in_block
;
538 uint64_t bytes_done
= 0;
543 qemu_iovec_init(&local_qiov
, qiov
->niov
);
545 while (ret
>= 0 && bytes
> 0) {
546 block_index
= offset
/ s
->block_size
;
547 offset_in_block
= offset
% s
->block_size
;
548 n_bytes
= MIN(bytes
, s
->block_size
- offset_in_block
);
550 logout("will read %u bytes starting at offset %" PRIu64
"\n",
553 /* prepare next AIO request */
554 bmap_entry
= le32_to_cpu(s
->bmap
[block_index
]);
555 if (!VDI_IS_ALLOCATED(bmap_entry
)) {
556 /* Block not allocated, return zeros, no need to wait. */
557 qemu_iovec_memset(qiov
, bytes_done
, 0, n_bytes
);
560 uint64_t data_offset
= s
->header
.offset_data
+
561 (uint64_t)bmap_entry
* s
->block_size
+
564 qemu_iovec_reset(&local_qiov
);
565 qemu_iovec_concat(&local_qiov
, qiov
, bytes_done
, n_bytes
);
567 ret
= bdrv_co_preadv(bs
->file
, data_offset
, n_bytes
,
570 logout("%u bytes read\n", n_bytes
);
574 bytes_done
+= n_bytes
;
577 qemu_iovec_destroy(&local_qiov
);
582 static int coroutine_fn
583 vdi_co_pwritev(BlockDriverState
*bs
, uint64_t offset
, uint64_t bytes
,
584 QEMUIOVector
*qiov
, int flags
)
586 BDRVVdiState
*s
= bs
->opaque
;
587 QEMUIOVector local_qiov
;
589 uint32_t block_index
;
590 uint32_t offset_in_block
;
592 uint32_t bmap_first
= VDI_UNALLOCATED
;
593 uint32_t bmap_last
= VDI_UNALLOCATED
;
594 uint8_t *block
= NULL
;
595 uint64_t bytes_done
= 0;
600 qemu_iovec_init(&local_qiov
, qiov
->niov
);
602 while (ret
>= 0 && bytes
> 0) {
603 block_index
= offset
/ s
->block_size
;
604 offset_in_block
= offset
% s
->block_size
;
605 n_bytes
= MIN(bytes
, s
->block_size
- offset_in_block
);
607 logout("will write %u bytes starting at offset %" PRIu64
"\n",
610 /* prepare next AIO request */
611 bmap_entry
= le32_to_cpu(s
->bmap
[block_index
]);
612 if (!VDI_IS_ALLOCATED(bmap_entry
)) {
613 /* Allocate new block and write to it. */
614 uint64_t data_offset
;
615 bmap_entry
= s
->header
.blocks_allocated
;
616 s
->bmap
[block_index
] = cpu_to_le32(bmap_entry
);
617 s
->header
.blocks_allocated
++;
618 data_offset
= s
->header
.offset_data
+
619 (uint64_t)bmap_entry
* s
->block_size
;
621 block
= g_malloc(s
->block_size
);
622 bmap_first
= block_index
;
624 bmap_last
= block_index
;
625 /* Copy data to be written to new block and zero unused parts. */
626 memset(block
, 0, offset_in_block
);
627 qemu_iovec_to_buf(qiov
, bytes_done
, block
+ offset_in_block
,
629 memset(block
+ offset_in_block
+ n_bytes
, 0,
630 s
->block_size
- n_bytes
- offset_in_block
);
632 /* Note that this coroutine does not yield anywhere from reading the
633 * bmap entry until here, so in regards to all the coroutines trying
634 * to write to this cluster, the one doing the allocation will
635 * always be the first to try to acquire the lock.
636 * Therefore, it is also the first that will actually be able to
637 * acquire the lock and thus the padded cluster is written before
638 * the other coroutines can write to the affected area. */
639 qemu_co_mutex_lock(&s
->write_lock
);
640 ret
= bdrv_pwrite(bs
->file
, data_offset
, block
, s
->block_size
);
641 qemu_co_mutex_unlock(&s
->write_lock
);
643 uint64_t data_offset
= s
->header
.offset_data
+
644 (uint64_t)bmap_entry
* s
->block_size
+
646 qemu_co_mutex_lock(&s
->write_lock
);
647 /* This lock is only used to make sure the following write operation
648 * is executed after the write issued by the coroutine allocating
649 * this cluster, therefore we do not need to keep it locked.
650 * As stated above, the allocating coroutine will always try to lock
651 * the mutex before all the other concurrent accesses to that
652 * cluster, therefore at this point we can be absolutely certain
653 * that that write operation has returned (there may be other writes
654 * in flight, but they do not concern this very operation). */
655 qemu_co_mutex_unlock(&s
->write_lock
);
657 qemu_iovec_reset(&local_qiov
);
658 qemu_iovec_concat(&local_qiov
, qiov
, bytes_done
, n_bytes
);
660 ret
= bdrv_co_pwritev(bs
->file
, data_offset
, n_bytes
,
666 bytes_done
+= n_bytes
;
668 logout("%u bytes written\n", n_bytes
);
671 qemu_iovec_destroy(&local_qiov
);
673 logout("finished data write\n");
679 /* One or more new blocks were allocated. */
680 VdiHeader
*header
= (VdiHeader
*) block
;
685 logout("now writing modified header\n");
686 assert(VDI_IS_ALLOCATED(bmap_first
));
688 vdi_header_to_le(header
);
689 ret
= bdrv_write(bs
->file
, 0, block
, 1);
697 logout("now writing modified block map entry %u...%u\n",
698 bmap_first
, bmap_last
);
699 /* Write modified sectors from block map. */
700 bmap_first
/= (SECTOR_SIZE
/ sizeof(uint32_t));
701 bmap_last
/= (SECTOR_SIZE
/ sizeof(uint32_t));
702 n_sectors
= bmap_last
- bmap_first
+ 1;
703 offset
= s
->bmap_sector
+ bmap_first
;
704 base
= ((uint8_t *)&s
->bmap
[0]) + bmap_first
* SECTOR_SIZE
;
705 logout("will write %u block map sectors starting from entry %u\n",
706 n_sectors
, bmap_first
);
707 ret
= bdrv_write(bs
->file
, offset
, base
, n_sectors
);
713 static int vdi_create(const char *filename
, QemuOpts
*opts
, Error
**errp
)
718 size_t block_size
= DEFAULT_CLUSTER_SIZE
;
719 uint32_t image_type
= VDI_TYPE_DYNAMIC
;
724 Error
*local_err
= NULL
;
725 BlockBackend
*blk
= NULL
;
726 uint32_t *bmap
= NULL
;
730 /* Read out options. */
731 bytes
= ROUND_UP(qemu_opt_get_size_del(opts
, BLOCK_OPT_SIZE
, 0),
733 #if defined(CONFIG_VDI_BLOCK_SIZE)
734 /* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */
735 block_size
= qemu_opt_get_size_del(opts
,
736 BLOCK_OPT_CLUSTER_SIZE
,
737 DEFAULT_CLUSTER_SIZE
);
739 #if defined(CONFIG_VDI_STATIC_IMAGE)
740 if (qemu_opt_get_bool_del(opts
, BLOCK_OPT_STATIC
, false)) {
741 image_type
= VDI_TYPE_STATIC
;
745 if (bytes
> VDI_DISK_SIZE_MAX
) {
747 error_setg(errp
, "Unsupported VDI image size (size is 0x%" PRIx64
748 ", max supported is 0x%" PRIx64
")",
749 bytes
, VDI_DISK_SIZE_MAX
);
753 ret
= bdrv_create_file(filename
, opts
, &local_err
);
755 error_propagate(errp
, local_err
);
759 blk
= blk_new_open(filename
, NULL
, NULL
,
760 BDRV_O_RDWR
| BDRV_O_PROTOCOL
, &local_err
);
762 error_propagate(errp
, local_err
);
767 blk_set_allow_write_beyond_eof(blk
, true);
769 /* We need enough blocks to store the given disk size,
770 so always round up. */
771 blocks
= DIV_ROUND_UP(bytes
, block_size
);
773 bmap_size
= blocks
* sizeof(uint32_t);
774 bmap_size
= ROUND_UP(bmap_size
, SECTOR_SIZE
);
776 memset(&header
, 0, sizeof(header
));
777 pstrcpy(header
.text
, sizeof(header
.text
), VDI_TEXT
);
778 header
.signature
= VDI_SIGNATURE
;
779 header
.version
= VDI_VERSION_1_1
;
780 header
.header_size
= 0x180;
781 header
.image_type
= image_type
;
782 header
.offset_bmap
= 0x200;
783 header
.offset_data
= 0x200 + bmap_size
;
784 header
.sector_size
= SECTOR_SIZE
;
785 header
.disk_size
= bytes
;
786 header
.block_size
= block_size
;
787 header
.blocks_in_image
= blocks
;
788 if (image_type
== VDI_TYPE_STATIC
) {
789 header
.blocks_allocated
= blocks
;
791 qemu_uuid_generate(&header
.uuid_image
);
792 qemu_uuid_generate(&header
.uuid_last_snap
);
793 /* There is no need to set header.uuid_link or header.uuid_parent here. */
794 #if defined(CONFIG_VDI_DEBUG)
795 vdi_header_print(&header
);
797 vdi_header_to_le(&header
);
798 ret
= blk_pwrite(blk
, offset
, &header
, sizeof(header
), 0);
800 error_setg(errp
, "Error writing header to %s", filename
);
803 offset
+= sizeof(header
);
806 bmap
= g_try_malloc0(bmap_size
);
809 error_setg(errp
, "Could not allocate bmap");
812 for (i
= 0; i
< blocks
; i
++) {
813 if (image_type
== VDI_TYPE_STATIC
) {
816 bmap
[i
] = VDI_UNALLOCATED
;
819 ret
= blk_pwrite(blk
, offset
, bmap
, bmap_size
, 0);
821 error_setg(errp
, "Error writing bmap to %s", filename
);
827 if (image_type
== VDI_TYPE_STATIC
) {
828 ret
= blk_truncate(blk
, offset
+ blocks
* block_size
);
830 error_setg(errp
, "Failed to statically allocate %s", filename
);
841 static void vdi_close(BlockDriverState
*bs
)
843 BDRVVdiState
*s
= bs
->opaque
;
847 migrate_del_blocker(s
->migration_blocker
);
848 error_free(s
->migration_blocker
);
851 static QemuOptsList vdi_create_opts
= {
852 .name
= "vdi-create-opts",
853 .head
= QTAILQ_HEAD_INITIALIZER(vdi_create_opts
.head
),
856 .name
= BLOCK_OPT_SIZE
,
857 .type
= QEMU_OPT_SIZE
,
858 .help
= "Virtual disk size"
860 #if defined(CONFIG_VDI_BLOCK_SIZE)
862 .name
= BLOCK_OPT_CLUSTER_SIZE
,
863 .type
= QEMU_OPT_SIZE
,
864 .help
= "VDI cluster (block) size",
865 .def_value_str
= stringify(DEFAULT_CLUSTER_SIZE
)
868 #if defined(CONFIG_VDI_STATIC_IMAGE)
870 .name
= BLOCK_OPT_STATIC
,
871 .type
= QEMU_OPT_BOOL
,
872 .help
= "VDI static (pre-allocated) image",
873 .def_value_str
= "off"
876 /* TODO: An additional option to set UUID values might be useful. */
877 { /* end of list */ }
881 static BlockDriver bdrv_vdi
= {
882 .format_name
= "vdi",
883 .instance_size
= sizeof(BDRVVdiState
),
884 .bdrv_probe
= vdi_probe
,
885 .bdrv_open
= vdi_open
,
886 .bdrv_close
= vdi_close
,
887 .bdrv_reopen_prepare
= vdi_reopen_prepare
,
888 .bdrv_create
= vdi_create
,
889 .bdrv_has_zero_init
= bdrv_has_zero_init_1
,
890 .bdrv_co_get_block_status
= vdi_co_get_block_status
,
891 .bdrv_make_empty
= vdi_make_empty
,
893 .bdrv_co_preadv
= vdi_co_preadv
,
894 #if defined(CONFIG_VDI_WRITE)
895 .bdrv_co_pwritev
= vdi_co_pwritev
,
898 .bdrv_get_info
= vdi_get_info
,
900 .create_opts
= &vdi_create_opts
,
901 .bdrv_check
= vdi_check
,
904 static void bdrv_vdi_init(void)
907 bdrv_register(&bdrv_vdi
);
910 block_init(bdrv_vdi_init
);