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/option.h"
58 #include "qemu/bswap.h"
59 #include "migration/blocker.h"
60 #include "qemu/coroutine.h"
61 #include "qemu/cutils.h"
62 #include "qemu/uuid.h"
64 /* Code configuration options. */
66 /* Enable debug messages. */
67 //~ #define CONFIG_VDI_DEBUG
69 /* Support write operations on VDI images. */
70 #define CONFIG_VDI_WRITE
72 /* Support non-standard block (cluster) size. This is untested.
73 * Maybe it will be needed for very large images.
75 //~ #define CONFIG_VDI_BLOCK_SIZE
77 /* Support static (fixed, pre-allocated) images. */
78 #define CONFIG_VDI_STATIC_IMAGE
80 /* Command line option for static images. */
81 #define BLOCK_OPT_STATIC "static"
84 #define MiB (KiB * KiB)
86 #define SECTOR_SIZE 512
87 #define DEFAULT_CLUSTER_SIZE (1 * MiB)
89 #if defined(CONFIG_VDI_DEBUG)
95 #define logout(fmt, ...) \
98 fprintf(stderr, "vdi\t%-24s" fmt, __func__, ##__VA_ARGS__); \
102 /* Image signature. */
103 #define VDI_SIGNATURE 0xbeda107f
106 #define VDI_VERSION_1_1 0x00010001
109 #define VDI_TYPE_DYNAMIC 1
110 #define VDI_TYPE_STATIC 2
112 /* Innotek / SUN images use these strings in header.text:
113 * "<<< innotek VirtualBox Disk Image >>>\n"
114 * "<<< Sun xVM VirtualBox Disk Image >>>\n"
115 * "<<< Sun VirtualBox Disk Image >>>\n"
116 * The value does not matter, so QEMU created images use a different text.
118 #define VDI_TEXT "<<< QEMU VM Virtual Disk Image >>>\n"
120 /* A never-allocated block; semantically arbitrary content. */
121 #define VDI_UNALLOCATED 0xffffffffU
123 /* A discarded (no longer allocated) block; semantically zero-filled. */
124 #define VDI_DISCARDED 0xfffffffeU
126 #define VDI_IS_ALLOCATED(X) ((X) < VDI_DISCARDED)
128 /* The bmap will take up VDI_BLOCKS_IN_IMAGE_MAX * sizeof(uint32_t) bytes; since
129 * the bmap is read and written in a single operation, its size needs to be
130 * limited to INT_MAX; furthermore, when opening an image, the bmap size is
131 * rounded up to be aligned on BDRV_SECTOR_SIZE.
132 * Therefore this should satisfy the following:
133 * VDI_BLOCKS_IN_IMAGE_MAX * sizeof(uint32_t) + BDRV_SECTOR_SIZE == INT_MAX + 1
134 * (INT_MAX + 1 is the first value not representable as an int)
135 * This guarantees that any value below or equal to the constant will, when
136 * multiplied by sizeof(uint32_t) and rounded up to a BDRV_SECTOR_SIZE boundary,
137 * still be below or equal to INT_MAX. */
138 #define VDI_BLOCKS_IN_IMAGE_MAX \
139 ((unsigned)((INT_MAX + 1u - BDRV_SECTOR_SIZE) / sizeof(uint32_t)))
140 #define VDI_DISK_SIZE_MAX ((uint64_t)VDI_BLOCKS_IN_IMAGE_MAX * \
141 (uint64_t)DEFAULT_CLUSTER_SIZE)
147 uint32_t header_size
;
149 uint32_t image_flags
;
150 char description
[256];
151 uint32_t offset_bmap
;
152 uint32_t offset_data
;
153 uint32_t cylinders
; /* disk geometry, unused here */
154 uint32_t heads
; /* disk geometry, unused here */
155 uint32_t sectors
; /* disk geometry, unused here */
156 uint32_t sector_size
;
160 uint32_t block_extra
; /* unused here */
161 uint32_t blocks_in_image
;
162 uint32_t blocks_allocated
;
164 QemuUUID uuid_last_snap
;
166 QemuUUID uuid_parent
;
168 } QEMU_PACKED VdiHeader
;
171 /* The block map entries are little endian (even in memory). */
173 /* Size of block (bytes). */
175 /* Size of block (sectors). */
176 uint32_t block_sectors
;
177 /* First sector of block map. */
178 uint32_t bmap_sector
;
179 /* VDI header (converted to host endianness). */
184 Error
*migration_blocker
;
187 static void vdi_header_to_cpu(VdiHeader
*header
)
189 le32_to_cpus(&header
->signature
);
190 le32_to_cpus(&header
->version
);
191 le32_to_cpus(&header
->header_size
);
192 le32_to_cpus(&header
->image_type
);
193 le32_to_cpus(&header
->image_flags
);
194 le32_to_cpus(&header
->offset_bmap
);
195 le32_to_cpus(&header
->offset_data
);
196 le32_to_cpus(&header
->cylinders
);
197 le32_to_cpus(&header
->heads
);
198 le32_to_cpus(&header
->sectors
);
199 le32_to_cpus(&header
->sector_size
);
200 le64_to_cpus(&header
->disk_size
);
201 le32_to_cpus(&header
->block_size
);
202 le32_to_cpus(&header
->block_extra
);
203 le32_to_cpus(&header
->blocks_in_image
);
204 le32_to_cpus(&header
->blocks_allocated
);
205 qemu_uuid_bswap(&header
->uuid_image
);
206 qemu_uuid_bswap(&header
->uuid_last_snap
);
207 qemu_uuid_bswap(&header
->uuid_link
);
208 qemu_uuid_bswap(&header
->uuid_parent
);
211 static void vdi_header_to_le(VdiHeader
*header
)
213 cpu_to_le32s(&header
->signature
);
214 cpu_to_le32s(&header
->version
);
215 cpu_to_le32s(&header
->header_size
);
216 cpu_to_le32s(&header
->image_type
);
217 cpu_to_le32s(&header
->image_flags
);
218 cpu_to_le32s(&header
->offset_bmap
);
219 cpu_to_le32s(&header
->offset_data
);
220 cpu_to_le32s(&header
->cylinders
);
221 cpu_to_le32s(&header
->heads
);
222 cpu_to_le32s(&header
->sectors
);
223 cpu_to_le32s(&header
->sector_size
);
224 cpu_to_le64s(&header
->disk_size
);
225 cpu_to_le32s(&header
->block_size
);
226 cpu_to_le32s(&header
->block_extra
);
227 cpu_to_le32s(&header
->blocks_in_image
);
228 cpu_to_le32s(&header
->blocks_allocated
);
229 qemu_uuid_bswap(&header
->uuid_image
);
230 qemu_uuid_bswap(&header
->uuid_last_snap
);
231 qemu_uuid_bswap(&header
->uuid_link
);
232 qemu_uuid_bswap(&header
->uuid_parent
);
235 #if defined(CONFIG_VDI_DEBUG)
236 static void vdi_header_print(VdiHeader
*header
)
239 logout("text %s", header
->text
);
240 logout("signature 0x%08x\n", header
->signature
);
241 logout("header size 0x%04x\n", header
->header_size
);
242 logout("image type 0x%04x\n", header
->image_type
);
243 logout("image flags 0x%04x\n", header
->image_flags
);
244 logout("description %s\n", header
->description
);
245 logout("offset bmap 0x%04x\n", header
->offset_bmap
);
246 logout("offset data 0x%04x\n", header
->offset_data
);
247 logout("cylinders 0x%04x\n", header
->cylinders
);
248 logout("heads 0x%04x\n", header
->heads
);
249 logout("sectors 0x%04x\n", header
->sectors
);
250 logout("sector size 0x%04x\n", header
->sector_size
);
251 logout("image size 0x%" PRIx64
" B (%" PRIu64
" MiB)\n",
252 header
->disk_size
, header
->disk_size
/ MiB
);
253 logout("block size 0x%04x\n", header
->block_size
);
254 logout("block extra 0x%04x\n", header
->block_extra
);
255 logout("blocks tot. 0x%04x\n", header
->blocks_in_image
);
256 logout("blocks all. 0x%04x\n", header
->blocks_allocated
);
257 uuid_unparse(header
->uuid_image
, uuid
);
258 logout("uuid image %s\n", uuid
);
259 uuid_unparse(header
->uuid_last_snap
, uuid
);
260 logout("uuid snap %s\n", uuid
);
261 uuid_unparse(header
->uuid_link
, uuid
);
262 logout("uuid link %s\n", uuid
);
263 uuid_unparse(header
->uuid_parent
, uuid
);
264 logout("uuid parent %s\n", uuid
);
268 static int vdi_check(BlockDriverState
*bs
, BdrvCheckResult
*res
,
271 /* TODO: additional checks possible. */
272 BDRVVdiState
*s
= (BDRVVdiState
*)bs
->opaque
;
273 uint32_t blocks_allocated
= 0;
282 bmap
= g_try_new(uint32_t, s
->header
.blocks_in_image
);
283 if (s
->header
.blocks_in_image
&& bmap
== NULL
) {
288 memset(bmap
, 0xff, s
->header
.blocks_in_image
* sizeof(uint32_t));
290 /* Check block map and value of blocks_allocated. */
291 for (block
= 0; block
< s
->header
.blocks_in_image
; block
++) {
292 uint32_t bmap_entry
= le32_to_cpu(s
->bmap
[block
]);
293 if (VDI_IS_ALLOCATED(bmap_entry
)) {
294 if (bmap_entry
< s
->header
.blocks_in_image
) {
296 if (!VDI_IS_ALLOCATED(bmap
[bmap_entry
])) {
297 bmap
[bmap_entry
] = bmap_entry
;
299 fprintf(stderr
, "ERROR: block index %" PRIu32
300 " also used by %" PRIu32
"\n", bmap
[bmap_entry
], bmap_entry
);
304 fprintf(stderr
, "ERROR: block index %" PRIu32
305 " too large, is %" PRIu32
"\n", block
, bmap_entry
);
310 if (blocks_allocated
!= s
->header
.blocks_allocated
) {
311 fprintf(stderr
, "ERROR: allocated blocks mismatch, is %" PRIu32
312 ", should be %" PRIu32
"\n",
313 blocks_allocated
, s
->header
.blocks_allocated
);
322 static int vdi_get_info(BlockDriverState
*bs
, BlockDriverInfo
*bdi
)
324 /* TODO: vdi_get_info would be needed for machine snapshots.
325 vm_state_offset is still missing. */
326 BDRVVdiState
*s
= (BDRVVdiState
*)bs
->opaque
;
328 bdi
->cluster_size
= s
->block_size
;
329 bdi
->vm_state_offset
= 0;
330 bdi
->unallocated_blocks_are_zero
= true;
334 static int vdi_make_empty(BlockDriverState
*bs
)
336 /* TODO: missing code. */
338 /* The return value for missing code must be 0, see block.c. */
342 static int vdi_probe(const uint8_t *buf
, int buf_size
, const char *filename
)
344 const VdiHeader
*header
= (const VdiHeader
*)buf
;
349 if (buf_size
< sizeof(*header
)) {
350 /* Header too small, no VDI. */
351 } else if (le32_to_cpu(header
->signature
) == VDI_SIGNATURE
) {
356 logout("no vdi image\n");
358 logout("%s", header
->text
);
364 static int vdi_open(BlockDriverState
*bs
, QDict
*options
, int flags
,
367 BDRVVdiState
*s
= bs
->opaque
;
371 Error
*local_err
= NULL
;
373 bs
->file
= bdrv_open_child(NULL
, options
, "file", bs
, &child_file
,
381 ret
= bdrv_read(bs
->file
, 0, (uint8_t *)&header
, 1);
386 vdi_header_to_cpu(&header
);
387 #if defined(CONFIG_VDI_DEBUG)
388 vdi_header_print(&header
);
391 if (header
.disk_size
> VDI_DISK_SIZE_MAX
) {
392 error_setg(errp
, "Unsupported VDI image size (size is 0x%" PRIx64
393 ", max supported is 0x%" PRIx64
")",
394 header
.disk_size
, VDI_DISK_SIZE_MAX
);
399 if (header
.disk_size
% SECTOR_SIZE
!= 0) {
400 /* 'VBoxManage convertfromraw' can create images with odd disk sizes.
401 We accept them but round the disk size to the next multiple of
403 logout("odd disk size %" PRIu64
" B, round up\n", header
.disk_size
);
404 header
.disk_size
= ROUND_UP(header
.disk_size
, SECTOR_SIZE
);
407 if (header
.signature
!= VDI_SIGNATURE
) {
408 error_setg(errp
, "Image not in VDI format (bad signature %08" PRIx32
409 ")", header
.signature
);
412 } else if (header
.version
!= VDI_VERSION_1_1
) {
413 error_setg(errp
, "unsupported VDI image (version %" PRIu32
".%" PRIu32
414 ")", header
.version
>> 16, header
.version
& 0xffff);
417 } else if (header
.offset_bmap
% SECTOR_SIZE
!= 0) {
418 /* We only support block maps which start on a sector boundary. */
419 error_setg(errp
, "unsupported VDI image (unaligned block map offset "
420 "0x%" PRIx32
")", header
.offset_bmap
);
423 } else if (header
.offset_data
% SECTOR_SIZE
!= 0) {
424 /* We only support data blocks which start on a sector boundary. */
425 error_setg(errp
, "unsupported VDI image (unaligned data offset 0x%"
426 PRIx32
")", header
.offset_data
);
429 } else if (header
.sector_size
!= SECTOR_SIZE
) {
430 error_setg(errp
, "unsupported VDI image (sector size %" PRIu32
431 " is not %u)", header
.sector_size
, SECTOR_SIZE
);
434 } else if (header
.block_size
!= DEFAULT_CLUSTER_SIZE
) {
435 error_setg(errp
, "unsupported VDI image (block size %" PRIu32
436 " is not %u)", header
.block_size
, DEFAULT_CLUSTER_SIZE
);
439 } else if (header
.disk_size
>
440 (uint64_t)header
.blocks_in_image
* header
.block_size
) {
441 error_setg(errp
, "unsupported VDI image (disk size %" PRIu64
", "
442 "image bitmap has room for %" PRIu64
")",
444 (uint64_t)header
.blocks_in_image
* header
.block_size
);
447 } else if (!qemu_uuid_is_null(&header
.uuid_link
)) {
448 error_setg(errp
, "unsupported VDI image (non-NULL link UUID)");
451 } else if (!qemu_uuid_is_null(&header
.uuid_parent
)) {
452 error_setg(errp
, "unsupported VDI image (non-NULL parent UUID)");
455 } else if (header
.blocks_in_image
> VDI_BLOCKS_IN_IMAGE_MAX
) {
456 error_setg(errp
, "unsupported VDI image "
457 "(too many blocks %u, max is %u)",
458 header
.blocks_in_image
, VDI_BLOCKS_IN_IMAGE_MAX
);
463 bs
->total_sectors
= header
.disk_size
/ SECTOR_SIZE
;
465 s
->block_size
= header
.block_size
;
466 s
->block_sectors
= header
.block_size
/ SECTOR_SIZE
;
467 s
->bmap_sector
= header
.offset_bmap
/ SECTOR_SIZE
;
470 bmap_size
= header
.blocks_in_image
* sizeof(uint32_t);
471 bmap_size
= DIV_ROUND_UP(bmap_size
, SECTOR_SIZE
);
472 s
->bmap
= qemu_try_blockalign(bs
->file
->bs
, bmap_size
* SECTOR_SIZE
);
473 if (s
->bmap
== NULL
) {
478 ret
= bdrv_read(bs
->file
, s
->bmap_sector
, (uint8_t *)s
->bmap
,
484 /* Disable migration when vdi images are used */
485 error_setg(&s
->migration_blocker
, "The vdi format used by node '%s' "
486 "does not support live migration",
487 bdrv_get_device_or_node_name(bs
));
488 ret
= migrate_add_blocker(s
->migration_blocker
, &local_err
);
490 error_propagate(errp
, local_err
);
491 error_free(s
->migration_blocker
);
495 qemu_co_rwlock_init(&s
->bmap_lock
);
506 static int vdi_reopen_prepare(BDRVReopenState
*state
,
507 BlockReopenQueue
*queue
, Error
**errp
)
512 static int64_t coroutine_fn
vdi_co_get_block_status(BlockDriverState
*bs
,
513 int64_t sector_num
, int nb_sectors
, int *pnum
, BlockDriverState
**file
)
515 /* TODO: Check for too large sector_num (in bdrv_is_allocated or here). */
516 BDRVVdiState
*s
= (BDRVVdiState
*)bs
->opaque
;
517 size_t bmap_index
= sector_num
/ s
->block_sectors
;
518 size_t sector_in_block
= sector_num
% s
->block_sectors
;
519 int n_sectors
= s
->block_sectors
- sector_in_block
;
520 uint32_t bmap_entry
= le32_to_cpu(s
->bmap
[bmap_index
]);
524 logout("%p, %" PRId64
", %d, %p\n", bs
, sector_num
, nb_sectors
, pnum
);
525 if (n_sectors
> nb_sectors
) {
526 n_sectors
= nb_sectors
;
529 result
= VDI_IS_ALLOCATED(bmap_entry
);
534 offset
= s
->header
.offset_data
+
535 (uint64_t)bmap_entry
* s
->block_size
+
536 sector_in_block
* SECTOR_SIZE
;
537 *file
= bs
->file
->bs
;
538 return BDRV_BLOCK_DATA
| BDRV_BLOCK_OFFSET_VALID
| offset
;
541 static int coroutine_fn
542 vdi_co_preadv(BlockDriverState
*bs
, uint64_t offset
, uint64_t bytes
,
543 QEMUIOVector
*qiov
, int flags
)
545 BDRVVdiState
*s
= bs
->opaque
;
546 QEMUIOVector local_qiov
;
548 uint32_t block_index
;
549 uint32_t offset_in_block
;
551 uint64_t bytes_done
= 0;
556 qemu_iovec_init(&local_qiov
, qiov
->niov
);
558 while (ret
>= 0 && bytes
> 0) {
559 block_index
= offset
/ s
->block_size
;
560 offset_in_block
= offset
% s
->block_size
;
561 n_bytes
= MIN(bytes
, s
->block_size
- offset_in_block
);
563 logout("will read %u bytes starting at offset %" PRIu64
"\n",
566 /* prepare next AIO request */
567 qemu_co_rwlock_rdlock(&s
->bmap_lock
);
568 bmap_entry
= le32_to_cpu(s
->bmap
[block_index
]);
569 qemu_co_rwlock_unlock(&s
->bmap_lock
);
570 if (!VDI_IS_ALLOCATED(bmap_entry
)) {
571 /* Block not allocated, return zeros, no need to wait. */
572 qemu_iovec_memset(qiov
, bytes_done
, 0, n_bytes
);
575 uint64_t data_offset
= s
->header
.offset_data
+
576 (uint64_t)bmap_entry
* s
->block_size
+
579 qemu_iovec_reset(&local_qiov
);
580 qemu_iovec_concat(&local_qiov
, qiov
, bytes_done
, n_bytes
);
582 ret
= bdrv_co_preadv(bs
->file
, data_offset
, n_bytes
,
585 logout("%u bytes read\n", n_bytes
);
589 bytes_done
+= n_bytes
;
592 qemu_iovec_destroy(&local_qiov
);
597 static int coroutine_fn
598 vdi_co_pwritev(BlockDriverState
*bs
, uint64_t offset
, uint64_t bytes
,
599 QEMUIOVector
*qiov
, int flags
)
601 BDRVVdiState
*s
= bs
->opaque
;
602 QEMUIOVector local_qiov
;
604 uint32_t block_index
;
605 uint32_t offset_in_block
;
607 uint64_t data_offset
;
608 uint32_t bmap_first
= VDI_UNALLOCATED
;
609 uint32_t bmap_last
= VDI_UNALLOCATED
;
610 uint8_t *block
= NULL
;
611 uint64_t bytes_done
= 0;
616 qemu_iovec_init(&local_qiov
, qiov
->niov
);
618 while (ret
>= 0 && bytes
> 0) {
619 block_index
= offset
/ s
->block_size
;
620 offset_in_block
= offset
% s
->block_size
;
621 n_bytes
= MIN(bytes
, s
->block_size
- offset_in_block
);
623 logout("will write %u bytes starting at offset %" PRIu64
"\n",
626 /* prepare next AIO request */
627 qemu_co_rwlock_rdlock(&s
->bmap_lock
);
628 bmap_entry
= le32_to_cpu(s
->bmap
[block_index
]);
629 if (!VDI_IS_ALLOCATED(bmap_entry
)) {
630 /* Allocate new block and write to it. */
631 uint64_t data_offset
;
632 qemu_co_rwlock_upgrade(&s
->bmap_lock
);
633 bmap_entry
= le32_to_cpu(s
->bmap
[block_index
]);
634 if (VDI_IS_ALLOCATED(bmap_entry
)) {
635 /* A concurrent allocation did the work for us. */
636 qemu_co_rwlock_downgrade(&s
->bmap_lock
);
637 goto nonallocating_write
;
640 bmap_entry
= s
->header
.blocks_allocated
;
641 s
->bmap
[block_index
] = cpu_to_le32(bmap_entry
);
642 s
->header
.blocks_allocated
++;
643 data_offset
= s
->header
.offset_data
+
644 (uint64_t)bmap_entry
* s
->block_size
;
646 block
= g_malloc(s
->block_size
);
647 bmap_first
= block_index
;
649 bmap_last
= block_index
;
650 /* Copy data to be written to new block and zero unused parts. */
651 memset(block
, 0, offset_in_block
);
652 qemu_iovec_to_buf(qiov
, bytes_done
, block
+ offset_in_block
,
654 memset(block
+ offset_in_block
+ n_bytes
, 0,
655 s
->block_size
- n_bytes
- offset_in_block
);
657 /* Write the new block under CoRwLock write-side protection,
658 * so this full-cluster write does not overlap a partial write
659 * of the same cluster, issued from the "else" branch.
661 ret
= bdrv_pwrite(bs
->file
, data_offset
, block
, s
->block_size
);
662 qemu_co_rwlock_unlock(&s
->bmap_lock
);
665 data_offset
= s
->header
.offset_data
+
666 (uint64_t)bmap_entry
* s
->block_size
+
668 qemu_co_rwlock_unlock(&s
->bmap_lock
);
670 qemu_iovec_reset(&local_qiov
);
671 qemu_iovec_concat(&local_qiov
, qiov
, bytes_done
, n_bytes
);
673 ret
= bdrv_co_pwritev(bs
->file
, data_offset
, n_bytes
,
679 bytes_done
+= n_bytes
;
681 logout("%u bytes written\n", n_bytes
);
684 qemu_iovec_destroy(&local_qiov
);
686 logout("finished data write\n");
692 /* One or more new blocks were allocated. */
693 VdiHeader
*header
= (VdiHeader
*) block
;
698 logout("now writing modified header\n");
699 assert(VDI_IS_ALLOCATED(bmap_first
));
701 vdi_header_to_le(header
);
702 ret
= bdrv_write(bs
->file
, 0, block
, 1);
710 logout("now writing modified block map entry %u...%u\n",
711 bmap_first
, bmap_last
);
712 /* Write modified sectors from block map. */
713 bmap_first
/= (SECTOR_SIZE
/ sizeof(uint32_t));
714 bmap_last
/= (SECTOR_SIZE
/ sizeof(uint32_t));
715 n_sectors
= bmap_last
- bmap_first
+ 1;
716 offset
= s
->bmap_sector
+ bmap_first
;
717 base
= ((uint8_t *)&s
->bmap
[0]) + bmap_first
* SECTOR_SIZE
;
718 logout("will write %u block map sectors starting from entry %u\n",
719 n_sectors
, bmap_first
);
720 ret
= bdrv_write(bs
->file
, offset
, base
, n_sectors
);
726 static int vdi_create(const char *filename
, QemuOpts
*opts
, Error
**errp
)
731 size_t block_size
= DEFAULT_CLUSTER_SIZE
;
732 uint32_t image_type
= VDI_TYPE_DYNAMIC
;
737 Error
*local_err
= NULL
;
738 BlockBackend
*blk
= NULL
;
739 uint32_t *bmap
= NULL
;
743 /* Read out options. */
744 bytes
= ROUND_UP(qemu_opt_get_size_del(opts
, BLOCK_OPT_SIZE
, 0),
746 #if defined(CONFIG_VDI_BLOCK_SIZE)
747 /* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */
748 block_size
= qemu_opt_get_size_del(opts
,
749 BLOCK_OPT_CLUSTER_SIZE
,
750 DEFAULT_CLUSTER_SIZE
);
752 #if defined(CONFIG_VDI_STATIC_IMAGE)
753 if (qemu_opt_get_bool_del(opts
, BLOCK_OPT_STATIC
, false)) {
754 image_type
= VDI_TYPE_STATIC
;
758 if (bytes
> VDI_DISK_SIZE_MAX
) {
760 error_setg(errp
, "Unsupported VDI image size (size is 0x%" PRIx64
761 ", max supported is 0x%" PRIx64
")",
762 bytes
, VDI_DISK_SIZE_MAX
);
766 ret
= bdrv_create_file(filename
, opts
, &local_err
);
768 error_propagate(errp
, local_err
);
772 blk
= blk_new_open(filename
, NULL
, NULL
,
773 BDRV_O_RDWR
| BDRV_O_RESIZE
| BDRV_O_PROTOCOL
,
776 error_propagate(errp
, local_err
);
781 blk_set_allow_write_beyond_eof(blk
, true);
783 /* We need enough blocks to store the given disk size,
784 so always round up. */
785 blocks
= DIV_ROUND_UP(bytes
, block_size
);
787 bmap_size
= blocks
* sizeof(uint32_t);
788 bmap_size
= ROUND_UP(bmap_size
, SECTOR_SIZE
);
790 memset(&header
, 0, sizeof(header
));
791 pstrcpy(header
.text
, sizeof(header
.text
), VDI_TEXT
);
792 header
.signature
= VDI_SIGNATURE
;
793 header
.version
= VDI_VERSION_1_1
;
794 header
.header_size
= 0x180;
795 header
.image_type
= image_type
;
796 header
.offset_bmap
= 0x200;
797 header
.offset_data
= 0x200 + bmap_size
;
798 header
.sector_size
= SECTOR_SIZE
;
799 header
.disk_size
= bytes
;
800 header
.block_size
= block_size
;
801 header
.blocks_in_image
= blocks
;
802 if (image_type
== VDI_TYPE_STATIC
) {
803 header
.blocks_allocated
= blocks
;
805 qemu_uuid_generate(&header
.uuid_image
);
806 qemu_uuid_generate(&header
.uuid_last_snap
);
807 /* There is no need to set header.uuid_link or header.uuid_parent here. */
808 #if defined(CONFIG_VDI_DEBUG)
809 vdi_header_print(&header
);
811 vdi_header_to_le(&header
);
812 ret
= blk_pwrite(blk
, offset
, &header
, sizeof(header
), 0);
814 error_setg(errp
, "Error writing header to %s", filename
);
817 offset
+= sizeof(header
);
820 bmap
= g_try_malloc0(bmap_size
);
823 error_setg(errp
, "Could not allocate bmap");
826 for (i
= 0; i
< blocks
; i
++) {
827 if (image_type
== VDI_TYPE_STATIC
) {
830 bmap
[i
] = VDI_UNALLOCATED
;
833 ret
= blk_pwrite(blk
, offset
, bmap
, bmap_size
, 0);
835 error_setg(errp
, "Error writing bmap to %s", filename
);
841 if (image_type
== VDI_TYPE_STATIC
) {
842 ret
= blk_truncate(blk
, offset
+ blocks
* block_size
,
843 PREALLOC_MODE_OFF
, errp
);
845 error_prepend(errp
, "Failed to statically allocate %s", filename
);
856 static void vdi_close(BlockDriverState
*bs
)
858 BDRVVdiState
*s
= bs
->opaque
;
862 migrate_del_blocker(s
->migration_blocker
);
863 error_free(s
->migration_blocker
);
866 static QemuOptsList vdi_create_opts
= {
867 .name
= "vdi-create-opts",
868 .head
= QTAILQ_HEAD_INITIALIZER(vdi_create_opts
.head
),
871 .name
= BLOCK_OPT_SIZE
,
872 .type
= QEMU_OPT_SIZE
,
873 .help
= "Virtual disk size"
875 #if defined(CONFIG_VDI_BLOCK_SIZE)
877 .name
= BLOCK_OPT_CLUSTER_SIZE
,
878 .type
= QEMU_OPT_SIZE
,
879 .help
= "VDI cluster (block) size",
880 .def_value_str
= stringify(DEFAULT_CLUSTER_SIZE
)
883 #if defined(CONFIG_VDI_STATIC_IMAGE)
885 .name
= BLOCK_OPT_STATIC
,
886 .type
= QEMU_OPT_BOOL
,
887 .help
= "VDI static (pre-allocated) image",
888 .def_value_str
= "off"
891 /* TODO: An additional option to set UUID values might be useful. */
892 { /* end of list */ }
896 static BlockDriver bdrv_vdi
= {
897 .format_name
= "vdi",
898 .instance_size
= sizeof(BDRVVdiState
),
899 .bdrv_probe
= vdi_probe
,
900 .bdrv_open
= vdi_open
,
901 .bdrv_close
= vdi_close
,
902 .bdrv_reopen_prepare
= vdi_reopen_prepare
,
903 .bdrv_child_perm
= bdrv_format_default_perms
,
904 .bdrv_create
= vdi_create
,
905 .bdrv_has_zero_init
= bdrv_has_zero_init_1
,
906 .bdrv_co_get_block_status
= vdi_co_get_block_status
,
907 .bdrv_make_empty
= vdi_make_empty
,
909 .bdrv_co_preadv
= vdi_co_preadv
,
910 #if defined(CONFIG_VDI_WRITE)
911 .bdrv_co_pwritev
= vdi_co_pwritev
,
914 .bdrv_get_info
= vdi_get_info
,
916 .create_opts
= &vdi_create_opts
,
917 .bdrv_check
= vdi_check
,
920 static void bdrv_vdi_init(void)
923 bdrv_register(&bdrv_vdi
);
926 block_init(bdrv_vdi_init
);