root / block / vdi.c @ 75411d23
History | View | Annotate | Download (29.1 kB)
1 |
/*
|
---|---|
2 |
* Block driver for the Virtual Disk Image (VDI) format
|
3 |
*
|
4 |
* Copyright (c) 2009 Stefan Weil
|
5 |
*
|
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.
|
10 |
*
|
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.
|
15 |
*
|
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/>.
|
18 |
*
|
19 |
* Reference:
|
20 |
* http://forums.virtualbox.org/viewtopic.php?t=8046
|
21 |
*
|
22 |
* This driver supports create / read / write operations on VDI images.
|
23 |
*
|
24 |
* Todo (see also TODO in code):
|
25 |
*
|
26 |
* Some features like snapshots are still missing.
|
27 |
*
|
28 |
* Deallocation of zero-filled blocks and shrinking images are missing, too
|
29 |
* (might be added to common block layer).
|
30 |
*
|
31 |
* Allocation of blocks could be optimized (less writes to block map and
|
32 |
* header).
|
33 |
*
|
34 |
* Read and write of adjacents blocks could be done in one operation
|
35 |
* (current code uses one operation per block (1 MiB).
|
36 |
*
|
37 |
* The code is not thread safe (missing locks for changes in header and
|
38 |
* block table, no problem with current QEMU).
|
39 |
*
|
40 |
* Hints:
|
41 |
*
|
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.
|
46 |
*
|
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.
|
50 |
*/
|
51 |
|
52 |
#include "qemu-common.h" |
53 |
#include "block_int.h" |
54 |
#include "module.h" |
55 |
|
56 |
#if defined(CONFIG_UUID)
|
57 |
#include <uuid/uuid.h> |
58 |
#else
|
59 |
/* TODO: move uuid emulation to some central place in QEMU. */
|
60 |
#include "sysemu.h" /* UUID_FMT */ |
61 |
typedef unsigned char uuid_t[16]; |
62 |
void uuid_generate(uuid_t out);
|
63 |
int uuid_is_null(const uuid_t uu); |
64 |
void uuid_unparse(const uuid_t uu, char *out); |
65 |
#endif
|
66 |
|
67 |
/* Code configuration options. */
|
68 |
|
69 |
/* Enable debug messages. */
|
70 |
//~ #define CONFIG_VDI_DEBUG
|
71 |
|
72 |
/* Support write operations on VDI images. */
|
73 |
#define CONFIG_VDI_WRITE
|
74 |
|
75 |
/* Support non-standard block (cluster) size. This is untested.
|
76 |
* Maybe it will be needed for very large images.
|
77 |
*/
|
78 |
//~ #define CONFIG_VDI_BLOCK_SIZE
|
79 |
|
80 |
/* Support static (fixed, pre-allocated) images. */
|
81 |
#define CONFIG_VDI_STATIC_IMAGE
|
82 |
|
83 |
/* Command line option for static images. */
|
84 |
#define BLOCK_OPT_STATIC "static" |
85 |
|
86 |
#define KiB 1024 |
87 |
#define MiB (KiB * KiB)
|
88 |
|
89 |
#define SECTOR_SIZE 512 |
90 |
|
91 |
#if defined(CONFIG_VDI_DEBUG)
|
92 |
#define logout(fmt, ...) \
|
93 |
fprintf(stderr, "vdi\t%-24s" fmt, __func__, ##__VA_ARGS__) |
94 |
#else
|
95 |
#define logout(fmt, ...) ((void)0) |
96 |
#endif
|
97 |
|
98 |
/* Image signature. */
|
99 |
#define VDI_SIGNATURE 0xbeda107f |
100 |
|
101 |
/* Image version. */
|
102 |
#define VDI_VERSION_1_1 0x00010001 |
103 |
|
104 |
/* Image type. */
|
105 |
#define VDI_TYPE_DYNAMIC 1 |
106 |
#define VDI_TYPE_STATIC 2 |
107 |
|
108 |
/* Innotek / SUN images use these strings in header.text:
|
109 |
* "<<< innotek VirtualBox Disk Image >>>\n"
|
110 |
* "<<< Sun xVM VirtualBox Disk Image >>>\n"
|
111 |
* "<<< Sun VirtualBox Disk Image >>>\n"
|
112 |
* The value does not matter, so QEMU created images use a different text.
|
113 |
*/
|
114 |
#define VDI_TEXT "<<< QEMU VM Virtual Disk Image >>>\n" |
115 |
|
116 |
/* Unallocated blocks use this index (no need to convert endianess). */
|
117 |
#define VDI_UNALLOCATED UINT32_MAX
|
118 |
|
119 |
#if !defined(CONFIG_UUID)
|
120 |
void uuid_generate(uuid_t out)
|
121 |
{ |
122 |
memset(out, 0, sizeof(out)); |
123 |
} |
124 |
|
125 |
int uuid_is_null(const uuid_t uu) |
126 |
{ |
127 |
uuid_t null_uuid = { 0 };
|
128 |
return memcmp(uu, null_uuid, sizeof(uu)) == 0; |
129 |
} |
130 |
|
131 |
void uuid_unparse(const uuid_t uu, char *out) |
132 |
{ |
133 |
snprintf(out, 37, UUID_FMT,
|
134 |
uu[0], uu[1], uu[2], uu[3], uu[4], uu[5], uu[6], uu[7], |
135 |
uu[8], uu[9], uu[10], uu[11], uu[12], uu[13], uu[14], uu[15]); |
136 |
} |
137 |
#endif
|
138 |
|
139 |
typedef struct { |
140 |
BlockDriverAIOCB common; |
141 |
int64_t sector_num; |
142 |
QEMUIOVector *qiov; |
143 |
uint8_t *buf; |
144 |
/* Total number of sectors. */
|
145 |
int nb_sectors;
|
146 |
/* Number of sectors for current AIO. */
|
147 |
int n_sectors;
|
148 |
/* New allocated block map entry. */
|
149 |
uint32_t bmap_first; |
150 |
uint32_t bmap_last; |
151 |
/* Buffer for new allocated block. */
|
152 |
void *block_buffer;
|
153 |
void *orig_buf;
|
154 |
int header_modified;
|
155 |
BlockDriverAIOCB *hd_aiocb; |
156 |
struct iovec hd_iov;
|
157 |
QEMUIOVector hd_qiov; |
158 |
QEMUBH *bh; |
159 |
} VdiAIOCB; |
160 |
|
161 |
typedef struct { |
162 |
char text[0x40]; |
163 |
uint32_t signature; |
164 |
uint32_t version; |
165 |
uint32_t header_size; |
166 |
uint32_t image_type; |
167 |
uint32_t image_flags; |
168 |
char description[256]; |
169 |
uint32_t offset_bmap; |
170 |
uint32_t offset_data; |
171 |
uint32_t cylinders; /* disk geometry, unused here */
|
172 |
uint32_t heads; /* disk geometry, unused here */
|
173 |
uint32_t sectors; /* disk geometry, unused here */
|
174 |
uint32_t sector_size; |
175 |
uint32_t unused1; |
176 |
uint64_t disk_size; |
177 |
uint32_t block_size; |
178 |
uint32_t block_extra; /* unused here */
|
179 |
uint32_t blocks_in_image; |
180 |
uint32_t blocks_allocated; |
181 |
uuid_t uuid_image; |
182 |
uuid_t uuid_last_snap; |
183 |
uuid_t uuid_link; |
184 |
uuid_t uuid_parent; |
185 |
uint64_t unused2[7];
|
186 |
} VdiHeader; |
187 |
|
188 |
typedef struct { |
189 |
/* The block map entries are little endian (even in memory). */
|
190 |
uint32_t *bmap; |
191 |
/* Size of block (bytes). */
|
192 |
uint32_t block_size; |
193 |
/* Size of block (sectors). */
|
194 |
uint32_t block_sectors; |
195 |
/* First sector of block map. */
|
196 |
uint32_t bmap_sector; |
197 |
/* VDI header (converted to host endianess). */
|
198 |
VdiHeader header; |
199 |
} BDRVVdiState; |
200 |
|
201 |
/* Change UUID from little endian (IPRT = VirtualBox format) to big endian
|
202 |
* format (network byte order, standard, see RFC 4122) and vice versa.
|
203 |
*/
|
204 |
static void uuid_convert(uuid_t uuid) |
205 |
{ |
206 |
bswap32s((uint32_t *)&uuid[0]);
|
207 |
bswap16s((uint16_t *)&uuid[4]);
|
208 |
bswap16s((uint16_t *)&uuid[6]);
|
209 |
} |
210 |
|
211 |
static void vdi_header_to_cpu(VdiHeader *header) |
212 |
{ |
213 |
le32_to_cpus(&header->signature); |
214 |
le32_to_cpus(&header->version); |
215 |
le32_to_cpus(&header->header_size); |
216 |
le32_to_cpus(&header->image_type); |
217 |
le32_to_cpus(&header->image_flags); |
218 |
le32_to_cpus(&header->offset_bmap); |
219 |
le32_to_cpus(&header->offset_data); |
220 |
le32_to_cpus(&header->cylinders); |
221 |
le32_to_cpus(&header->heads); |
222 |
le32_to_cpus(&header->sectors); |
223 |
le32_to_cpus(&header->sector_size); |
224 |
le64_to_cpus(&header->disk_size); |
225 |
le32_to_cpus(&header->block_size); |
226 |
le32_to_cpus(&header->block_extra); |
227 |
le32_to_cpus(&header->blocks_in_image); |
228 |
le32_to_cpus(&header->blocks_allocated); |
229 |
uuid_convert(header->uuid_image); |
230 |
uuid_convert(header->uuid_last_snap); |
231 |
uuid_convert(header->uuid_link); |
232 |
uuid_convert(header->uuid_parent); |
233 |
} |
234 |
|
235 |
static void vdi_header_to_le(VdiHeader *header) |
236 |
{ |
237 |
cpu_to_le32s(&header->signature); |
238 |
cpu_to_le32s(&header->version); |
239 |
cpu_to_le32s(&header->header_size); |
240 |
cpu_to_le32s(&header->image_type); |
241 |
cpu_to_le32s(&header->image_flags); |
242 |
cpu_to_le32s(&header->offset_bmap); |
243 |
cpu_to_le32s(&header->offset_data); |
244 |
cpu_to_le32s(&header->cylinders); |
245 |
cpu_to_le32s(&header->heads); |
246 |
cpu_to_le32s(&header->sectors); |
247 |
cpu_to_le32s(&header->sector_size); |
248 |
cpu_to_le64s(&header->disk_size); |
249 |
cpu_to_le32s(&header->block_size); |
250 |
cpu_to_le32s(&header->block_extra); |
251 |
cpu_to_le32s(&header->blocks_in_image); |
252 |
cpu_to_le32s(&header->blocks_allocated); |
253 |
cpu_to_le32s(&header->blocks_allocated); |
254 |
uuid_convert(header->uuid_image); |
255 |
uuid_convert(header->uuid_last_snap); |
256 |
uuid_convert(header->uuid_link); |
257 |
uuid_convert(header->uuid_parent); |
258 |
} |
259 |
|
260 |
#if defined(CONFIG_VDI_DEBUG)
|
261 |
static void vdi_header_print(VdiHeader *header) |
262 |
{ |
263 |
char uuid[37]; |
264 |
logout("text %s", header->text);
|
265 |
logout("signature 0x%04x\n", header->signature);
|
266 |
logout("header size 0x%04x\n", header->header_size);
|
267 |
logout("image type 0x%04x\n", header->image_type);
|
268 |
logout("image flags 0x%04x\n", header->image_flags);
|
269 |
logout("description %s\n", header->description);
|
270 |
logout("offset bmap 0x%04x\n", header->offset_bmap);
|
271 |
logout("offset data 0x%04x\n", header->offset_data);
|
272 |
logout("cylinders 0x%04x\n", header->cylinders);
|
273 |
logout("heads 0x%04x\n", header->heads);
|
274 |
logout("sectors 0x%04x\n", header->sectors);
|
275 |
logout("sector size 0x%04x\n", header->sector_size);
|
276 |
logout("image size 0x%" PRIx64 " B (%" PRIu64 " MiB)\n", |
277 |
header->disk_size, header->disk_size / MiB); |
278 |
logout("block size 0x%04x\n", header->block_size);
|
279 |
logout("block extra 0x%04x\n", header->block_extra);
|
280 |
logout("blocks tot. 0x%04x\n", header->blocks_in_image);
|
281 |
logout("blocks all. 0x%04x\n", header->blocks_allocated);
|
282 |
uuid_unparse(header->uuid_image, uuid); |
283 |
logout("uuid image %s\n", uuid);
|
284 |
uuid_unparse(header->uuid_last_snap, uuid); |
285 |
logout("uuid snap %s\n", uuid);
|
286 |
uuid_unparse(header->uuid_link, uuid); |
287 |
logout("uuid link %s\n", uuid);
|
288 |
uuid_unparse(header->uuid_parent, uuid); |
289 |
logout("uuid parent %s\n", uuid);
|
290 |
} |
291 |
#endif
|
292 |
|
293 |
static int vdi_check(BlockDriverState *bs, BdrvCheckResult *res) |
294 |
{ |
295 |
/* TODO: additional checks possible. */
|
296 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
297 |
uint32_t blocks_allocated = 0;
|
298 |
uint32_t block; |
299 |
uint32_t *bmap; |
300 |
logout("\n");
|
301 |
|
302 |
bmap = qemu_malloc(s->header.blocks_in_image * sizeof(uint32_t));
|
303 |
memset(bmap, 0xff, s->header.blocks_in_image * sizeof(uint32_t)); |
304 |
|
305 |
/* Check block map and value of blocks_allocated. */
|
306 |
for (block = 0; block < s->header.blocks_in_image; block++) { |
307 |
uint32_t bmap_entry = le32_to_cpu(s->bmap[block]); |
308 |
if (bmap_entry != VDI_UNALLOCATED) {
|
309 |
if (bmap_entry < s->header.blocks_in_image) {
|
310 |
blocks_allocated++; |
311 |
if (bmap[bmap_entry] == VDI_UNALLOCATED) {
|
312 |
bmap[bmap_entry] = bmap_entry; |
313 |
} else {
|
314 |
fprintf(stderr, "ERROR: block index %" PRIu32
|
315 |
" also used by %" PRIu32 "\n", bmap[bmap_entry], bmap_entry); |
316 |
res->corruptions++; |
317 |
} |
318 |
} else {
|
319 |
fprintf(stderr, "ERROR: block index %" PRIu32
|
320 |
" too large, is %" PRIu32 "\n", block, bmap_entry); |
321 |
res->corruptions++; |
322 |
} |
323 |
} |
324 |
} |
325 |
if (blocks_allocated != s->header.blocks_allocated) {
|
326 |
fprintf(stderr, "ERROR: allocated blocks mismatch, is %" PRIu32
|
327 |
", should be %" PRIu32 "\n", |
328 |
blocks_allocated, s->header.blocks_allocated); |
329 |
res->corruptions++; |
330 |
} |
331 |
|
332 |
qemu_free(bmap); |
333 |
|
334 |
return 0; |
335 |
} |
336 |
|
337 |
static int vdi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
338 |
{ |
339 |
/* TODO: vdi_get_info would be needed for machine snapshots.
|
340 |
vm_state_offset is still missing. */
|
341 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
342 |
logout("\n");
|
343 |
bdi->cluster_size = s->block_size; |
344 |
bdi->vm_state_offset = 0;
|
345 |
return 0; |
346 |
} |
347 |
|
348 |
static int vdi_make_empty(BlockDriverState *bs) |
349 |
{ |
350 |
/* TODO: missing code. */
|
351 |
logout("\n");
|
352 |
/* The return value for missing code must be 0, see block.c. */
|
353 |
return 0; |
354 |
} |
355 |
|
356 |
static int vdi_probe(const uint8_t *buf, int buf_size, const char *filename) |
357 |
{ |
358 |
const VdiHeader *header = (const VdiHeader *)buf; |
359 |
int result = 0; |
360 |
|
361 |
logout("\n");
|
362 |
|
363 |
if (buf_size < sizeof(*header)) { |
364 |
/* Header too small, no VDI. */
|
365 |
} else if (le32_to_cpu(header->signature) == VDI_SIGNATURE) { |
366 |
result = 100;
|
367 |
} |
368 |
|
369 |
if (result == 0) { |
370 |
logout("no vdi image\n");
|
371 |
} else {
|
372 |
logout("%s", header->text);
|
373 |
} |
374 |
|
375 |
return result;
|
376 |
} |
377 |
|
378 |
static int vdi_open(BlockDriverState *bs, int flags) |
379 |
{ |
380 |
BDRVVdiState *s = bs->opaque; |
381 |
VdiHeader header; |
382 |
size_t bmap_size; |
383 |
|
384 |
logout("\n");
|
385 |
|
386 |
if (bdrv_read(bs->file, 0, (uint8_t *)&header, 1) < 0) { |
387 |
goto fail;
|
388 |
} |
389 |
|
390 |
vdi_header_to_cpu(&header); |
391 |
#if defined(CONFIG_VDI_DEBUG)
|
392 |
vdi_header_print(&header); |
393 |
#endif
|
394 |
|
395 |
if (header.disk_size % SECTOR_SIZE != 0) { |
396 |
/* 'VBoxManage convertfromraw' can create images with odd disk sizes.
|
397 |
We accept them but round the disk size to the next multiple of
|
398 |
SECTOR_SIZE. */
|
399 |
logout("odd disk size %" PRIu64 " B, round up\n", header.disk_size); |
400 |
header.disk_size += SECTOR_SIZE - 1;
|
401 |
header.disk_size &= ~(SECTOR_SIZE - 1);
|
402 |
} |
403 |
|
404 |
if (header.version != VDI_VERSION_1_1) {
|
405 |
logout("unsupported version %u.%u\n",
|
406 |
header.version >> 16, header.version & 0xffff); |
407 |
goto fail;
|
408 |
} else if (header.offset_bmap % SECTOR_SIZE != 0) { |
409 |
/* We only support block maps which start on a sector boundary. */
|
410 |
logout("unsupported block map offset 0x%x B\n", header.offset_bmap);
|
411 |
goto fail;
|
412 |
} else if (header.offset_data % SECTOR_SIZE != 0) { |
413 |
/* We only support data blocks which start on a sector boundary. */
|
414 |
logout("unsupported data offset 0x%x B\n", header.offset_data);
|
415 |
goto fail;
|
416 |
} else if (header.sector_size != SECTOR_SIZE) { |
417 |
logout("unsupported sector size %u B\n", header.sector_size);
|
418 |
goto fail;
|
419 |
} else if (header.block_size != 1 * MiB) { |
420 |
logout("unsupported block size %u B\n", header.block_size);
|
421 |
goto fail;
|
422 |
} else if (header.disk_size > |
423 |
(uint64_t)header.blocks_in_image * header.block_size) { |
424 |
logout("unsupported disk size %" PRIu64 " B\n", header.disk_size); |
425 |
goto fail;
|
426 |
} else if (!uuid_is_null(header.uuid_link)) { |
427 |
logout("link uuid != 0, unsupported\n");
|
428 |
goto fail;
|
429 |
} else if (!uuid_is_null(header.uuid_parent)) { |
430 |
logout("parent uuid != 0, unsupported\n");
|
431 |
goto fail;
|
432 |
} |
433 |
|
434 |
bs->total_sectors = header.disk_size / SECTOR_SIZE; |
435 |
|
436 |
s->block_size = header.block_size; |
437 |
s->block_sectors = header.block_size / SECTOR_SIZE; |
438 |
s->bmap_sector = header.offset_bmap / SECTOR_SIZE; |
439 |
s->header = header; |
440 |
|
441 |
bmap_size = header.blocks_in_image * sizeof(uint32_t);
|
442 |
bmap_size = (bmap_size + SECTOR_SIZE - 1) / SECTOR_SIZE;
|
443 |
if (bmap_size > 0) { |
444 |
s->bmap = qemu_malloc(bmap_size * SECTOR_SIZE); |
445 |
} |
446 |
if (bdrv_read(bs->file, s->bmap_sector, (uint8_t *)s->bmap, bmap_size) < 0) { |
447 |
goto fail_free_bmap;
|
448 |
} |
449 |
|
450 |
return 0; |
451 |
|
452 |
fail_free_bmap:
|
453 |
qemu_free(s->bmap); |
454 |
|
455 |
fail:
|
456 |
return -1; |
457 |
} |
458 |
|
459 |
static int vdi_is_allocated(BlockDriverState *bs, int64_t sector_num, |
460 |
int nb_sectors, int *pnum) |
461 |
{ |
462 |
/* TODO: Check for too large sector_num (in bdrv_is_allocated or here). */
|
463 |
BDRVVdiState *s = (BDRVVdiState *)bs->opaque; |
464 |
size_t bmap_index = sector_num / s->block_sectors; |
465 |
size_t sector_in_block = sector_num % s->block_sectors; |
466 |
int n_sectors = s->block_sectors - sector_in_block;
|
467 |
uint32_t bmap_entry = le32_to_cpu(s->bmap[bmap_index]); |
468 |
logout("%p, %" PRId64 ", %d, %p\n", bs, sector_num, nb_sectors, pnum); |
469 |
if (n_sectors > nb_sectors) {
|
470 |
n_sectors = nb_sectors; |
471 |
} |
472 |
*pnum = n_sectors; |
473 |
return bmap_entry != VDI_UNALLOCATED;
|
474 |
} |
475 |
|
476 |
static void vdi_aio_cancel(BlockDriverAIOCB *blockacb) |
477 |
{ |
478 |
/* TODO: This code is untested. How can I get it executed? */
|
479 |
VdiAIOCB *acb = container_of(blockacb, VdiAIOCB, common); |
480 |
logout("\n");
|
481 |
if (acb->hd_aiocb) {
|
482 |
bdrv_aio_cancel(acb->hd_aiocb); |
483 |
} |
484 |
qemu_aio_release(acb); |
485 |
} |
486 |
|
487 |
static AIOPool vdi_aio_pool = {
|
488 |
.aiocb_size = sizeof(VdiAIOCB),
|
489 |
.cancel = vdi_aio_cancel, |
490 |
}; |
491 |
|
492 |
static VdiAIOCB *vdi_aio_setup(BlockDriverState *bs, int64_t sector_num,
|
493 |
QEMUIOVector *qiov, int nb_sectors,
|
494 |
BlockDriverCompletionFunc *cb, void *opaque, int is_write) |
495 |
{ |
496 |
VdiAIOCB *acb; |
497 |
|
498 |
logout("%p, %" PRId64 ", %p, %d, %p, %p, %d\n", |
499 |
bs, sector_num, qiov, nb_sectors, cb, opaque, is_write); |
500 |
|
501 |
acb = qemu_aio_get(&vdi_aio_pool, bs, cb, opaque); |
502 |
if (acb) {
|
503 |
acb->hd_aiocb = NULL;
|
504 |
acb->sector_num = sector_num; |
505 |
acb->qiov = qiov; |
506 |
if (qiov->niov > 1) { |
507 |
acb->buf = qemu_blockalign(bs, qiov->size); |
508 |
acb->orig_buf = acb->buf; |
509 |
if (is_write) {
|
510 |
qemu_iovec_to_buffer(qiov, acb->buf); |
511 |
} |
512 |
} else {
|
513 |
acb->buf = (uint8_t *)qiov->iov->iov_base; |
514 |
} |
515 |
acb->nb_sectors = nb_sectors; |
516 |
acb->n_sectors = 0;
|
517 |
acb->bmap_first = VDI_UNALLOCATED; |
518 |
acb->bmap_last = VDI_UNALLOCATED; |
519 |
acb->block_buffer = NULL;
|
520 |
acb->header_modified = 0;
|
521 |
} |
522 |
return acb;
|
523 |
} |
524 |
|
525 |
static int vdi_schedule_bh(QEMUBHFunc *cb, VdiAIOCB *acb) |
526 |
{ |
527 |
logout("\n");
|
528 |
|
529 |
if (acb->bh) {
|
530 |
return -EIO;
|
531 |
} |
532 |
|
533 |
acb->bh = qemu_bh_new(cb, acb); |
534 |
if (!acb->bh) {
|
535 |
return -EIO;
|
536 |
} |
537 |
|
538 |
qemu_bh_schedule(acb->bh); |
539 |
|
540 |
return 0; |
541 |
} |
542 |
|
543 |
static void vdi_aio_read_cb(void *opaque, int ret); |
544 |
|
545 |
static void vdi_aio_read_bh(void *opaque) |
546 |
{ |
547 |
VdiAIOCB *acb = opaque; |
548 |
logout("\n");
|
549 |
qemu_bh_delete(acb->bh); |
550 |
acb->bh = NULL;
|
551 |
vdi_aio_read_cb(opaque, 0);
|
552 |
} |
553 |
|
554 |
static void vdi_aio_read_cb(void *opaque, int ret) |
555 |
{ |
556 |
VdiAIOCB *acb = opaque; |
557 |
BlockDriverState *bs = acb->common.bs; |
558 |
BDRVVdiState *s = bs->opaque; |
559 |
uint32_t bmap_entry; |
560 |
uint32_t block_index; |
561 |
uint32_t sector_in_block; |
562 |
uint32_t n_sectors; |
563 |
|
564 |
logout("%u sectors read\n", acb->n_sectors);
|
565 |
|
566 |
acb->hd_aiocb = NULL;
|
567 |
|
568 |
if (ret < 0) { |
569 |
goto done;
|
570 |
} |
571 |
|
572 |
acb->nb_sectors -= acb->n_sectors; |
573 |
|
574 |
if (acb->nb_sectors == 0) { |
575 |
/* request completed */
|
576 |
ret = 0;
|
577 |
goto done;
|
578 |
} |
579 |
|
580 |
acb->sector_num += acb->n_sectors; |
581 |
acb->buf += acb->n_sectors * SECTOR_SIZE; |
582 |
|
583 |
block_index = acb->sector_num / s->block_sectors; |
584 |
sector_in_block = acb->sector_num % s->block_sectors; |
585 |
n_sectors = s->block_sectors - sector_in_block; |
586 |
if (n_sectors > acb->nb_sectors) {
|
587 |
n_sectors = acb->nb_sectors; |
588 |
} |
589 |
|
590 |
logout("will read %u sectors starting at sector %" PRIu64 "\n", |
591 |
n_sectors, acb->sector_num); |
592 |
|
593 |
/* prepare next AIO request */
|
594 |
acb->n_sectors = n_sectors; |
595 |
bmap_entry = le32_to_cpu(s->bmap[block_index]); |
596 |
if (bmap_entry == VDI_UNALLOCATED) {
|
597 |
/* Block not allocated, return zeros, no need to wait. */
|
598 |
memset(acb->buf, 0, n_sectors * SECTOR_SIZE);
|
599 |
ret = vdi_schedule_bh(vdi_aio_read_bh, acb); |
600 |
if (ret < 0) { |
601 |
goto done;
|
602 |
} |
603 |
} else {
|
604 |
uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
605 |
(uint64_t)bmap_entry * s->block_sectors + |
606 |
sector_in_block; |
607 |
acb->hd_iov.iov_base = (void *)acb->buf;
|
608 |
acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
609 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
610 |
acb->hd_aiocb = bdrv_aio_readv(bs->file, offset, &acb->hd_qiov, |
611 |
n_sectors, vdi_aio_read_cb, acb); |
612 |
if (acb->hd_aiocb == NULL) { |
613 |
goto done;
|
614 |
} |
615 |
} |
616 |
return;
|
617 |
done:
|
618 |
if (acb->qiov->niov > 1) { |
619 |
qemu_iovec_from_buffer(acb->qiov, acb->orig_buf, acb->qiov->size); |
620 |
qemu_vfree(acb->orig_buf); |
621 |
} |
622 |
acb->common.cb(acb->common.opaque, ret); |
623 |
qemu_aio_release(acb); |
624 |
} |
625 |
|
626 |
static BlockDriverAIOCB *vdi_aio_readv(BlockDriverState *bs,
|
627 |
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
628 |
BlockDriverCompletionFunc *cb, void *opaque)
|
629 |
{ |
630 |
VdiAIOCB *acb; |
631 |
logout("\n");
|
632 |
acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
|
633 |
if (!acb) {
|
634 |
return NULL; |
635 |
} |
636 |
vdi_aio_read_cb(acb, 0);
|
637 |
return &acb->common;
|
638 |
} |
639 |
|
640 |
static void vdi_aio_write_cb(void *opaque, int ret) |
641 |
{ |
642 |
VdiAIOCB *acb = opaque; |
643 |
BlockDriverState *bs = acb->common.bs; |
644 |
BDRVVdiState *s = bs->opaque; |
645 |
uint32_t bmap_entry; |
646 |
uint32_t block_index; |
647 |
uint32_t sector_in_block; |
648 |
uint32_t n_sectors; |
649 |
|
650 |
acb->hd_aiocb = NULL;
|
651 |
|
652 |
if (ret < 0) { |
653 |
goto done;
|
654 |
} |
655 |
|
656 |
acb->nb_sectors -= acb->n_sectors; |
657 |
acb->sector_num += acb->n_sectors; |
658 |
acb->buf += acb->n_sectors * SECTOR_SIZE; |
659 |
|
660 |
if (acb->nb_sectors == 0) { |
661 |
logout("finished data write\n");
|
662 |
acb->n_sectors = 0;
|
663 |
if (acb->header_modified) {
|
664 |
VdiHeader *header = acb->block_buffer; |
665 |
logout("now writing modified header\n");
|
666 |
assert(acb->bmap_first != VDI_UNALLOCATED); |
667 |
*header = s->header; |
668 |
vdi_header_to_le(header); |
669 |
acb->header_modified = 0;
|
670 |
acb->hd_iov.iov_base = acb->block_buffer; |
671 |
acb->hd_iov.iov_len = SECTOR_SIZE; |
672 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
673 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, 0, &acb->hd_qiov, 1, |
674 |
vdi_aio_write_cb, acb); |
675 |
if (acb->hd_aiocb == NULL) { |
676 |
goto done;
|
677 |
} |
678 |
return;
|
679 |
} else if (acb->bmap_first != VDI_UNALLOCATED) { |
680 |
/* One or more new blocks were allocated. */
|
681 |
uint64_t offset; |
682 |
uint32_t bmap_first; |
683 |
uint32_t bmap_last; |
684 |
qemu_free(acb->block_buffer); |
685 |
acb->block_buffer = NULL;
|
686 |
bmap_first = acb->bmap_first; |
687 |
bmap_last = acb->bmap_last; |
688 |
logout("now writing modified block map entry %u...%u\n",
|
689 |
bmap_first, bmap_last); |
690 |
/* Write modified sectors from block map. */
|
691 |
bmap_first /= (SECTOR_SIZE / sizeof(uint32_t));
|
692 |
bmap_last /= (SECTOR_SIZE / sizeof(uint32_t));
|
693 |
n_sectors = bmap_last - bmap_first + 1;
|
694 |
offset = s->bmap_sector + bmap_first; |
695 |
acb->bmap_first = VDI_UNALLOCATED; |
696 |
acb->hd_iov.iov_base = (void *)((uint8_t *)&s->bmap[0] + |
697 |
bmap_first * SECTOR_SIZE); |
698 |
acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
699 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
700 |
logout("will write %u block map sectors starting from entry %u\n",
|
701 |
n_sectors, bmap_first); |
702 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov, |
703 |
n_sectors, vdi_aio_write_cb, acb); |
704 |
if (acb->hd_aiocb == NULL) { |
705 |
goto done;
|
706 |
} |
707 |
return;
|
708 |
} |
709 |
ret = 0;
|
710 |
goto done;
|
711 |
} |
712 |
|
713 |
logout("%u sectors written\n", acb->n_sectors);
|
714 |
|
715 |
block_index = acb->sector_num / s->block_sectors; |
716 |
sector_in_block = acb->sector_num % s->block_sectors; |
717 |
n_sectors = s->block_sectors - sector_in_block; |
718 |
if (n_sectors > acb->nb_sectors) {
|
719 |
n_sectors = acb->nb_sectors; |
720 |
} |
721 |
|
722 |
logout("will write %u sectors starting at sector %" PRIu64 "\n", |
723 |
n_sectors, acb->sector_num); |
724 |
|
725 |
/* prepare next AIO request */
|
726 |
acb->n_sectors = n_sectors; |
727 |
bmap_entry = le32_to_cpu(s->bmap[block_index]); |
728 |
if (bmap_entry == VDI_UNALLOCATED) {
|
729 |
/* Allocate new block and write to it. */
|
730 |
uint64_t offset; |
731 |
uint8_t *block; |
732 |
bmap_entry = s->header.blocks_allocated; |
733 |
s->bmap[block_index] = cpu_to_le32(bmap_entry); |
734 |
s->header.blocks_allocated++; |
735 |
offset = s->header.offset_data / SECTOR_SIZE + |
736 |
(uint64_t)bmap_entry * s->block_sectors; |
737 |
block = acb->block_buffer; |
738 |
if (block == NULL) { |
739 |
block = qemu_mallocz(s->block_size); |
740 |
acb->block_buffer = block; |
741 |
acb->bmap_first = block_index; |
742 |
assert(!acb->header_modified); |
743 |
acb->header_modified = 1;
|
744 |
} |
745 |
acb->bmap_last = block_index; |
746 |
memcpy(block + sector_in_block * SECTOR_SIZE, |
747 |
acb->buf, n_sectors * SECTOR_SIZE); |
748 |
acb->hd_iov.iov_base = (void *)block;
|
749 |
acb->hd_iov.iov_len = s->block_size; |
750 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
751 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, |
752 |
&acb->hd_qiov, s->block_sectors, |
753 |
vdi_aio_write_cb, acb); |
754 |
if (acb->hd_aiocb == NULL) { |
755 |
goto done;
|
756 |
} |
757 |
} else {
|
758 |
uint64_t offset = s->header.offset_data / SECTOR_SIZE + |
759 |
(uint64_t)bmap_entry * s->block_sectors + |
760 |
sector_in_block; |
761 |
acb->hd_iov.iov_base = (void *)acb->buf;
|
762 |
acb->hd_iov.iov_len = n_sectors * SECTOR_SIZE; |
763 |
qemu_iovec_init_external(&acb->hd_qiov, &acb->hd_iov, 1);
|
764 |
acb->hd_aiocb = bdrv_aio_writev(bs->file, offset, &acb->hd_qiov, |
765 |
n_sectors, vdi_aio_write_cb, acb); |
766 |
if (acb->hd_aiocb == NULL) { |
767 |
goto done;
|
768 |
} |
769 |
} |
770 |
|
771 |
return;
|
772 |
|
773 |
done:
|
774 |
if (acb->qiov->niov > 1) { |
775 |
qemu_vfree(acb->orig_buf); |
776 |
} |
777 |
acb->common.cb(acb->common.opaque, ret); |
778 |
qemu_aio_release(acb); |
779 |
} |
780 |
|
781 |
static BlockDriverAIOCB *vdi_aio_writev(BlockDriverState *bs,
|
782 |
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
|
783 |
BlockDriverCompletionFunc *cb, void *opaque)
|
784 |
{ |
785 |
VdiAIOCB *acb; |
786 |
logout("\n");
|
787 |
acb = vdi_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
|
788 |
if (!acb) {
|
789 |
return NULL; |
790 |
} |
791 |
vdi_aio_write_cb(acb, 0);
|
792 |
return &acb->common;
|
793 |
} |
794 |
|
795 |
static int vdi_create(const char *filename, QEMUOptionParameter *options) |
796 |
{ |
797 |
int fd;
|
798 |
int result = 0; |
799 |
uint64_t bytes = 0;
|
800 |
uint32_t blocks; |
801 |
size_t block_size = 1 * MiB;
|
802 |
uint32_t image_type = VDI_TYPE_DYNAMIC; |
803 |
VdiHeader header; |
804 |
size_t i; |
805 |
size_t bmap_size; |
806 |
uint32_t *bmap; |
807 |
|
808 |
logout("\n");
|
809 |
|
810 |
/* Read out options. */
|
811 |
while (options && options->name) {
|
812 |
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
|
813 |
bytes = options->value.n; |
814 |
#if defined(CONFIG_VDI_BLOCK_SIZE)
|
815 |
} else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) { |
816 |
if (options->value.n) {
|
817 |
/* TODO: Additional checks (SECTOR_SIZE * 2^n, ...). */
|
818 |
block_size = options->value.n; |
819 |
} |
820 |
#endif
|
821 |
#if defined(CONFIG_VDI_STATIC_IMAGE)
|
822 |
} else if (!strcmp(options->name, BLOCK_OPT_STATIC)) { |
823 |
if (options->value.n) {
|
824 |
image_type = VDI_TYPE_STATIC; |
825 |
} |
826 |
#endif
|
827 |
} |
828 |
options++; |
829 |
} |
830 |
|
831 |
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, |
832 |
0644);
|
833 |
if (fd < 0) { |
834 |
return -errno;
|
835 |
} |
836 |
|
837 |
/* We need enough blocks to store the given disk size,
|
838 |
so always round up. */
|
839 |
blocks = (bytes + block_size - 1) / block_size;
|
840 |
|
841 |
bmap_size = blocks * sizeof(uint32_t);
|
842 |
bmap_size = ((bmap_size + SECTOR_SIZE - 1) & ~(SECTOR_SIZE -1)); |
843 |
|
844 |
memset(&header, 0, sizeof(header)); |
845 |
pstrcpy(header.text, sizeof(header.text), VDI_TEXT);
|
846 |
header.signature = VDI_SIGNATURE; |
847 |
header.version = VDI_VERSION_1_1; |
848 |
header.header_size = 0x180;
|
849 |
header.image_type = image_type; |
850 |
header.offset_bmap = 0x200;
|
851 |
header.offset_data = 0x200 + bmap_size;
|
852 |
header.sector_size = SECTOR_SIZE; |
853 |
header.disk_size = bytes; |
854 |
header.block_size = block_size; |
855 |
header.blocks_in_image = blocks; |
856 |
if (image_type == VDI_TYPE_STATIC) {
|
857 |
header.blocks_allocated = blocks; |
858 |
} |
859 |
uuid_generate(header.uuid_image); |
860 |
uuid_generate(header.uuid_last_snap); |
861 |
/* There is no need to set header.uuid_link or header.uuid_parent here. */
|
862 |
#if defined(CONFIG_VDI_DEBUG)
|
863 |
vdi_header_print(&header); |
864 |
#endif
|
865 |
vdi_header_to_le(&header); |
866 |
if (write(fd, &header, sizeof(header)) < 0) { |
867 |
result = -errno; |
868 |
} |
869 |
|
870 |
bmap = NULL;
|
871 |
if (bmap_size > 0) { |
872 |
bmap = (uint32_t *)qemu_mallocz(bmap_size); |
873 |
} |
874 |
for (i = 0; i < blocks; i++) { |
875 |
if (image_type == VDI_TYPE_STATIC) {
|
876 |
bmap[i] = i; |
877 |
} else {
|
878 |
bmap[i] = VDI_UNALLOCATED; |
879 |
} |
880 |
} |
881 |
if (write(fd, bmap, bmap_size) < 0) { |
882 |
result = -errno; |
883 |
} |
884 |
qemu_free(bmap); |
885 |
if (image_type == VDI_TYPE_STATIC) {
|
886 |
if (ftruncate(fd, sizeof(header) + bmap_size + blocks * block_size)) { |
887 |
result = -errno; |
888 |
} |
889 |
} |
890 |
|
891 |
if (close(fd) < 0) { |
892 |
result = -errno; |
893 |
} |
894 |
|
895 |
return result;
|
896 |
} |
897 |
|
898 |
static void vdi_close(BlockDriverState *bs) |
899 |
{ |
900 |
} |
901 |
|
902 |
static int vdi_flush(BlockDriverState *bs) |
903 |
{ |
904 |
logout("\n");
|
905 |
return bdrv_flush(bs->file);
|
906 |
} |
907 |
|
908 |
|
909 |
static QEMUOptionParameter vdi_create_options[] = {
|
910 |
{ |
911 |
.name = BLOCK_OPT_SIZE, |
912 |
.type = OPT_SIZE, |
913 |
.help = "Virtual disk size"
|
914 |
}, |
915 |
#if defined(CONFIG_VDI_BLOCK_SIZE)
|
916 |
{ |
917 |
.name = BLOCK_OPT_CLUSTER_SIZE, |
918 |
.type = OPT_SIZE, |
919 |
.help = "VDI cluster (block) size"
|
920 |
}, |
921 |
#endif
|
922 |
#if defined(CONFIG_VDI_STATIC_IMAGE)
|
923 |
{ |
924 |
.name = BLOCK_OPT_STATIC, |
925 |
.type = OPT_FLAG, |
926 |
.help = "VDI static (pre-allocated) image"
|
927 |
}, |
928 |
#endif
|
929 |
/* TODO: An additional option to set UUID values might be useful. */
|
930 |
{ NULL }
|
931 |
}; |
932 |
|
933 |
static BlockDriver bdrv_vdi = {
|
934 |
.format_name = "vdi",
|
935 |
.instance_size = sizeof(BDRVVdiState),
|
936 |
.bdrv_probe = vdi_probe, |
937 |
.bdrv_open = vdi_open, |
938 |
.bdrv_close = vdi_close, |
939 |
.bdrv_create = vdi_create, |
940 |
.bdrv_flush = vdi_flush, |
941 |
.bdrv_is_allocated = vdi_is_allocated, |
942 |
.bdrv_make_empty = vdi_make_empty, |
943 |
|
944 |
.bdrv_aio_readv = vdi_aio_readv, |
945 |
#if defined(CONFIG_VDI_WRITE)
|
946 |
.bdrv_aio_writev = vdi_aio_writev, |
947 |
#endif
|
948 |
|
949 |
.bdrv_get_info = vdi_get_info, |
950 |
|
951 |
.create_options = vdi_create_options, |
952 |
.bdrv_check = vdi_check, |
953 |
}; |
954 |
|
955 |
static void bdrv_vdi_init(void) |
956 |
{ |
957 |
logout("\n");
|
958 |
bdrv_register(&bdrv_vdi); |
959 |
} |
960 |
|
961 |
block_init(bdrv_vdi_init); |