root / block.c @ ea2384d3
History | View | Annotate | Download (14.3 kB)
1 |
/*
|
---|---|
2 |
* QEMU System Emulator block driver
|
3 |
*
|
4 |
* Copyright (c) 2003 Fabrice Bellard
|
5 |
*
|
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:
|
12 |
*
|
13 |
* The above copyright notice and this permission notice shall be included in
|
14 |
* all copies or substantial portions of the Software.
|
15 |
*
|
16 |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
17 |
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
18 |
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
19 |
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
20 |
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
21 |
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
22 |
* THE SOFTWARE.
|
23 |
*/
|
24 |
#include "vl.h" |
25 |
#include "block_int.h" |
26 |
|
27 |
static BlockDriverState *bdrv_first;
|
28 |
static BlockDriver *first_drv;
|
29 |
|
30 |
void bdrv_register(BlockDriver *bdrv)
|
31 |
{ |
32 |
bdrv->next = first_drv; |
33 |
first_drv = bdrv; |
34 |
} |
35 |
|
36 |
/* create a new block device (by default it is empty) */
|
37 |
BlockDriverState *bdrv_new(const char *device_name) |
38 |
{ |
39 |
BlockDriverState **pbs, *bs; |
40 |
|
41 |
bs = qemu_mallocz(sizeof(BlockDriverState));
|
42 |
if(!bs)
|
43 |
return NULL; |
44 |
pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
|
45 |
if (device_name[0] != '\0') { |
46 |
/* insert at the end */
|
47 |
pbs = &bdrv_first; |
48 |
while (*pbs != NULL) |
49 |
pbs = &(*pbs)->next; |
50 |
*pbs = bs; |
51 |
} |
52 |
return bs;
|
53 |
} |
54 |
|
55 |
BlockDriver *bdrv_find_format(const char *format_name) |
56 |
{ |
57 |
BlockDriver *drv1; |
58 |
for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) { |
59 |
if (!strcmp(drv1->format_name, format_name))
|
60 |
return drv1;
|
61 |
} |
62 |
return NULL; |
63 |
} |
64 |
|
65 |
int bdrv_create(BlockDriver *drv,
|
66 |
const char *filename, int64_t size_in_sectors, |
67 |
const char *backing_file, int flags) |
68 |
{ |
69 |
if (!drv->bdrv_create)
|
70 |
return -ENOTSUP;
|
71 |
return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
|
72 |
} |
73 |
|
74 |
/* XXX: race condition possible */
|
75 |
static void get_tmp_filename(char *filename, int size) |
76 |
{ |
77 |
int fd;
|
78 |
pstrcpy(filename, size, "/tmp/vl.XXXXXX");
|
79 |
fd = mkstemp(filename); |
80 |
close(fd); |
81 |
} |
82 |
|
83 |
static BlockDriver *find_image_format(const char *filename) |
84 |
{ |
85 |
int fd, ret, score, score_max;
|
86 |
BlockDriver *drv1, *drv; |
87 |
uint8_t buf[1024];
|
88 |
|
89 |
fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE); |
90 |
if (fd < 0) |
91 |
return NULL; |
92 |
ret = read(fd, buf, sizeof(buf));
|
93 |
if (ret < 0) { |
94 |
close(fd); |
95 |
return NULL; |
96 |
} |
97 |
close(fd); |
98 |
|
99 |
drv = NULL;
|
100 |
score_max = 0;
|
101 |
for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) { |
102 |
score = drv1->bdrv_probe(buf, ret, filename); |
103 |
if (score > score_max) {
|
104 |
score_max = score; |
105 |
drv = drv1; |
106 |
} |
107 |
} |
108 |
return drv;
|
109 |
} |
110 |
|
111 |
int bdrv_open(BlockDriverState *bs, const char *filename, int snapshot) |
112 |
{ |
113 |
return bdrv_open2(bs, filename, snapshot, NULL); |
114 |
} |
115 |
|
116 |
int bdrv_open2(BlockDriverState *bs, const char *filename, int snapshot, |
117 |
BlockDriver *drv) |
118 |
{ |
119 |
int ret;
|
120 |
char tmp_filename[1024]; |
121 |
|
122 |
bs->read_only = 0;
|
123 |
bs->is_temporary = 0;
|
124 |
bs->encrypted = 0;
|
125 |
|
126 |
if (snapshot) {
|
127 |
BlockDriverState *bs1; |
128 |
int64_t total_size; |
129 |
|
130 |
/* if snapshot, we create a temporary backing file and open it
|
131 |
instead of opening 'filename' directly */
|
132 |
|
133 |
/* if there is a backing file, use it */
|
134 |
bs1 = bdrv_new("");
|
135 |
if (!bs1) {
|
136 |
return -1; |
137 |
} |
138 |
if (bdrv_open(bs1, filename, 0) < 0) { |
139 |
bdrv_delete(bs1); |
140 |
return -1; |
141 |
} |
142 |
total_size = bs1->total_sectors; |
143 |
bdrv_delete(bs1); |
144 |
|
145 |
get_tmp_filename(tmp_filename, sizeof(tmp_filename));
|
146 |
/* XXX: use cow for linux as it is more efficient ? */
|
147 |
if (bdrv_create(&bdrv_qcow, tmp_filename,
|
148 |
total_size, filename, 0) < 0) { |
149 |
return -1; |
150 |
} |
151 |
filename = tmp_filename; |
152 |
bs->is_temporary = 1;
|
153 |
} |
154 |
|
155 |
pstrcpy(bs->filename, sizeof(bs->filename), filename);
|
156 |
if (!drv) {
|
157 |
drv = find_image_format(filename); |
158 |
if (!drv)
|
159 |
return -1; |
160 |
} |
161 |
bs->drv = drv; |
162 |
bs->opaque = qemu_mallocz(drv->instance_size); |
163 |
if (bs->opaque == NULL && drv->instance_size > 0) |
164 |
return -1; |
165 |
|
166 |
ret = drv->bdrv_open(bs, filename); |
167 |
if (ret < 0) { |
168 |
qemu_free(bs->opaque); |
169 |
return -1; |
170 |
} |
171 |
#ifndef _WIN32
|
172 |
if (bs->is_temporary) {
|
173 |
unlink(filename); |
174 |
} |
175 |
#endif
|
176 |
if (bs->backing_file[0] != '\0' && drv->bdrv_is_allocated) { |
177 |
/* if there is a backing file, use it */
|
178 |
bs->backing_hd = bdrv_new("");
|
179 |
if (!bs->backing_hd) {
|
180 |
fail:
|
181 |
bdrv_close(bs); |
182 |
return -1; |
183 |
} |
184 |
if (bdrv_open(bs->backing_hd, bs->backing_file, 0) < 0) |
185 |
goto fail;
|
186 |
} |
187 |
|
188 |
bs->inserted = 1;
|
189 |
|
190 |
/* call the change callback */
|
191 |
if (bs->change_cb)
|
192 |
bs->change_cb(bs->change_opaque); |
193 |
|
194 |
return 0; |
195 |
} |
196 |
|
197 |
void bdrv_close(BlockDriverState *bs)
|
198 |
{ |
199 |
if (bs->inserted) {
|
200 |
if (bs->backing_hd)
|
201 |
bdrv_delete(bs->backing_hd); |
202 |
bs->drv->bdrv_close(bs); |
203 |
qemu_free(bs->opaque); |
204 |
#ifdef _WIN32
|
205 |
if (bs->is_temporary) {
|
206 |
unlink(bs->filename); |
207 |
} |
208 |
#endif
|
209 |
bs->opaque = NULL;
|
210 |
bs->drv = NULL;
|
211 |
bs->inserted = 0;
|
212 |
|
213 |
/* call the change callback */
|
214 |
if (bs->change_cb)
|
215 |
bs->change_cb(bs->change_opaque); |
216 |
} |
217 |
} |
218 |
|
219 |
void bdrv_delete(BlockDriverState *bs)
|
220 |
{ |
221 |
/* XXX: remove the driver list */
|
222 |
bdrv_close(bs); |
223 |
qemu_free(bs); |
224 |
} |
225 |
|
226 |
/* commit COW file into the raw image */
|
227 |
int bdrv_commit(BlockDriverState *bs)
|
228 |
{ |
229 |
int64_t i; |
230 |
int n, j;
|
231 |
unsigned char sector[512]; |
232 |
|
233 |
if (!bs->inserted)
|
234 |
return -ENOENT;
|
235 |
|
236 |
if (bs->read_only) {
|
237 |
return -EACCES;
|
238 |
} |
239 |
|
240 |
if (!bs->backing_hd) {
|
241 |
return -ENOTSUP;
|
242 |
} |
243 |
|
244 |
for (i = 0; i < bs->total_sectors;) { |
245 |
if (bs->drv->bdrv_is_allocated(bs, i, 65536, &n)) { |
246 |
for(j = 0; j < n; j++) { |
247 |
if (bdrv_read(bs, i, sector, 1) != 0) { |
248 |
return -EIO;
|
249 |
} |
250 |
|
251 |
if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) { |
252 |
return -EIO;
|
253 |
} |
254 |
i++; |
255 |
} |
256 |
} else {
|
257 |
i += n; |
258 |
} |
259 |
} |
260 |
return 0; |
261 |
} |
262 |
|
263 |
/* return -1 if error */
|
264 |
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
|
265 |
uint8_t *buf, int nb_sectors)
|
266 |
{ |
267 |
int ret, n;
|
268 |
BlockDriver *drv = bs->drv; |
269 |
|
270 |
if (!bs->inserted)
|
271 |
return -1; |
272 |
|
273 |
while (nb_sectors > 0) { |
274 |
if (sector_num == 0 && bs->boot_sector_enabled) { |
275 |
memcpy(buf, bs->boot_sector_data, 512);
|
276 |
n = 1;
|
277 |
} else if (bs->backing_hd) { |
278 |
if (drv->bdrv_is_allocated(bs, sector_num, nb_sectors, &n)) {
|
279 |
ret = drv->bdrv_read(bs, sector_num, buf, n); |
280 |
if (ret < 0) |
281 |
return -1; |
282 |
} else {
|
283 |
/* read from the base image */
|
284 |
ret = bdrv_read(bs->backing_hd, sector_num, buf, n); |
285 |
if (ret < 0) |
286 |
return -1; |
287 |
} |
288 |
} else {
|
289 |
ret = drv->bdrv_read(bs, sector_num, buf, nb_sectors); |
290 |
if (ret < 0) |
291 |
return -1; |
292 |
/* no need to loop */
|
293 |
break;
|
294 |
} |
295 |
nb_sectors -= n; |
296 |
sector_num += n; |
297 |
buf += n * 512;
|
298 |
} |
299 |
return 0; |
300 |
} |
301 |
|
302 |
/* return -1 if error */
|
303 |
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
|
304 |
const uint8_t *buf, int nb_sectors) |
305 |
{ |
306 |
if (!bs->inserted)
|
307 |
return -1; |
308 |
if (bs->read_only)
|
309 |
return -1; |
310 |
return bs->drv->bdrv_write(bs, sector_num, buf, nb_sectors);
|
311 |
} |
312 |
|
313 |
void bdrv_get_geometry(BlockDriverState *bs, int64_t *nb_sectors_ptr)
|
314 |
{ |
315 |
*nb_sectors_ptr = bs->total_sectors; |
316 |
} |
317 |
|
318 |
/* force a given boot sector. */
|
319 |
void bdrv_set_boot_sector(BlockDriverState *bs, const uint8_t *data, int size) |
320 |
{ |
321 |
bs->boot_sector_enabled = 1;
|
322 |
if (size > 512) |
323 |
size = 512;
|
324 |
memcpy(bs->boot_sector_data, data, size); |
325 |
memset(bs->boot_sector_data + size, 0, 512 - size); |
326 |
} |
327 |
|
328 |
void bdrv_set_geometry_hint(BlockDriverState *bs,
|
329 |
int cyls, int heads, int secs) |
330 |
{ |
331 |
bs->cyls = cyls; |
332 |
bs->heads = heads; |
333 |
bs->secs = secs; |
334 |
} |
335 |
|
336 |
void bdrv_set_type_hint(BlockDriverState *bs, int type) |
337 |
{ |
338 |
bs->type = type; |
339 |
bs->removable = ((type == BDRV_TYPE_CDROM || |
340 |
type == BDRV_TYPE_FLOPPY)); |
341 |
} |
342 |
|
343 |
void bdrv_get_geometry_hint(BlockDriverState *bs,
|
344 |
int *pcyls, int *pheads, int *psecs) |
345 |
{ |
346 |
*pcyls = bs->cyls; |
347 |
*pheads = bs->heads; |
348 |
*psecs = bs->secs; |
349 |
} |
350 |
|
351 |
int bdrv_get_type_hint(BlockDriverState *bs)
|
352 |
{ |
353 |
return bs->type;
|
354 |
} |
355 |
|
356 |
int bdrv_is_removable(BlockDriverState *bs)
|
357 |
{ |
358 |
return bs->removable;
|
359 |
} |
360 |
|
361 |
int bdrv_is_read_only(BlockDriverState *bs)
|
362 |
{ |
363 |
return bs->read_only;
|
364 |
} |
365 |
|
366 |
int bdrv_is_inserted(BlockDriverState *bs)
|
367 |
{ |
368 |
return bs->inserted;
|
369 |
} |
370 |
|
371 |
int bdrv_is_locked(BlockDriverState *bs)
|
372 |
{ |
373 |
return bs->locked;
|
374 |
} |
375 |
|
376 |
void bdrv_set_locked(BlockDriverState *bs, int locked) |
377 |
{ |
378 |
bs->locked = locked; |
379 |
} |
380 |
|
381 |
void bdrv_set_change_cb(BlockDriverState *bs,
|
382 |
void (*change_cb)(void *opaque), void *opaque) |
383 |
{ |
384 |
bs->change_cb = change_cb; |
385 |
bs->change_opaque = opaque; |
386 |
} |
387 |
|
388 |
int bdrv_is_encrypted(BlockDriverState *bs)
|
389 |
{ |
390 |
if (bs->backing_hd && bs->backing_hd->encrypted)
|
391 |
return 1; |
392 |
return bs->encrypted;
|
393 |
} |
394 |
|
395 |
int bdrv_set_key(BlockDriverState *bs, const char *key) |
396 |
{ |
397 |
int ret;
|
398 |
if (bs->backing_hd && bs->backing_hd->encrypted) {
|
399 |
ret = bdrv_set_key(bs->backing_hd, key); |
400 |
if (ret < 0) |
401 |
return ret;
|
402 |
if (!bs->encrypted)
|
403 |
return 0; |
404 |
} |
405 |
if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
|
406 |
return -1; |
407 |
return bs->drv->bdrv_set_key(bs, key);
|
408 |
} |
409 |
|
410 |
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size) |
411 |
{ |
412 |
if (!bs->inserted || !bs->drv) {
|
413 |
buf[0] = '\0'; |
414 |
} else {
|
415 |
pstrcpy(buf, buf_size, bs->drv->format_name); |
416 |
} |
417 |
} |
418 |
|
419 |
void bdrv_iterate_format(void (*it)(void *opaque, const char *name), |
420 |
void *opaque)
|
421 |
{ |
422 |
BlockDriver *drv; |
423 |
|
424 |
for (drv = first_drv; drv != NULL; drv = drv->next) { |
425 |
it(opaque, drv->format_name); |
426 |
} |
427 |
} |
428 |
|
429 |
BlockDriverState *bdrv_find(const char *name) |
430 |
{ |
431 |
BlockDriverState *bs; |
432 |
|
433 |
for (bs = bdrv_first; bs != NULL; bs = bs->next) { |
434 |
if (!strcmp(name, bs->device_name))
|
435 |
return bs;
|
436 |
} |
437 |
return NULL; |
438 |
} |
439 |
|
440 |
void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque) |
441 |
{ |
442 |
BlockDriverState *bs; |
443 |
|
444 |
for (bs = bdrv_first; bs != NULL; bs = bs->next) { |
445 |
it(opaque, bs->device_name); |
446 |
} |
447 |
} |
448 |
|
449 |
const char *bdrv_get_device_name(BlockDriverState *bs) |
450 |
{ |
451 |
return bs->device_name;
|
452 |
} |
453 |
|
454 |
void bdrv_info(void) |
455 |
{ |
456 |
BlockDriverState *bs; |
457 |
|
458 |
for (bs = bdrv_first; bs != NULL; bs = bs->next) { |
459 |
term_printf("%s:", bs->device_name);
|
460 |
term_printf(" type=");
|
461 |
switch(bs->type) {
|
462 |
case BDRV_TYPE_HD:
|
463 |
term_printf("hd");
|
464 |
break;
|
465 |
case BDRV_TYPE_CDROM:
|
466 |
term_printf("cdrom");
|
467 |
break;
|
468 |
case BDRV_TYPE_FLOPPY:
|
469 |
term_printf("floppy");
|
470 |
break;
|
471 |
} |
472 |
term_printf(" removable=%d", bs->removable);
|
473 |
if (bs->removable) {
|
474 |
term_printf(" locked=%d", bs->locked);
|
475 |
} |
476 |
if (bs->inserted) {
|
477 |
term_printf(" file=%s", bs->filename);
|
478 |
if (bs->backing_file[0] != '\0') |
479 |
term_printf(" backing_file=%s", bs->backing_file);
|
480 |
term_printf(" ro=%d", bs->read_only);
|
481 |
term_printf(" drv=%s", bs->drv->format_name);
|
482 |
if (bs->encrypted)
|
483 |
term_printf(" encrypted");
|
484 |
} else {
|
485 |
term_printf(" [not inserted]");
|
486 |
} |
487 |
term_printf("\n");
|
488 |
} |
489 |
} |
490 |
|
491 |
|
492 |
/**************************************************************/
|
493 |
/* RAW block driver */
|
494 |
|
495 |
typedef struct BDRVRawState { |
496 |
int fd;
|
497 |
} BDRVRawState; |
498 |
|
499 |
static int raw_probe(const uint8_t *buf, int buf_size, const char *filename) |
500 |
{ |
501 |
return 1; /* maybe */ |
502 |
} |
503 |
|
504 |
static int raw_open(BlockDriverState *bs, const char *filename) |
505 |
{ |
506 |
BDRVRawState *s = bs->opaque; |
507 |
int fd;
|
508 |
int64_t size; |
509 |
|
510 |
fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE); |
511 |
if (fd < 0) { |
512 |
fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE); |
513 |
if (fd < 0) |
514 |
return -1; |
515 |
bs->read_only = 1;
|
516 |
} |
517 |
size = lseek64(fd, 0, SEEK_END);
|
518 |
bs->total_sectors = size / 512;
|
519 |
s->fd = fd; |
520 |
return 0; |
521 |
} |
522 |
|
523 |
static int raw_read(BlockDriverState *bs, int64_t sector_num, |
524 |
uint8_t *buf, int nb_sectors)
|
525 |
{ |
526 |
BDRVRawState *s = bs->opaque; |
527 |
int ret;
|
528 |
|
529 |
lseek64(s->fd, sector_num * 512, SEEK_SET);
|
530 |
ret = read(s->fd, buf, nb_sectors * 512);
|
531 |
if (ret != nb_sectors * 512) |
532 |
return -1; |
533 |
return 0; |
534 |
} |
535 |
|
536 |
static int raw_write(BlockDriverState *bs, int64_t sector_num, |
537 |
const uint8_t *buf, int nb_sectors) |
538 |
{ |
539 |
BDRVRawState *s = bs->opaque; |
540 |
int ret;
|
541 |
|
542 |
lseek64(s->fd, sector_num * 512, SEEK_SET);
|
543 |
ret = write(s->fd, buf, nb_sectors * 512);
|
544 |
if (ret != nb_sectors * 512) |
545 |
return -1; |
546 |
return 0; |
547 |
} |
548 |
|
549 |
static int raw_close(BlockDriverState *bs) |
550 |
{ |
551 |
BDRVRawState *s = bs->opaque; |
552 |
close(s->fd); |
553 |
} |
554 |
|
555 |
static int raw_create(const char *filename, int64_t total_size, |
556 |
const char *backing_file, int flags) |
557 |
{ |
558 |
int fd;
|
559 |
|
560 |
if (flags || backing_file)
|
561 |
return -ENOTSUP;
|
562 |
|
563 |
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE, |
564 |
0644);
|
565 |
if (fd < 0) |
566 |
return -EIO;
|
567 |
ftruncate64(fd, total_size * 512);
|
568 |
close(fd); |
569 |
return 0; |
570 |
} |
571 |
|
572 |
BlockDriver bdrv_raw = { |
573 |
"raw",
|
574 |
sizeof(BDRVRawState),
|
575 |
raw_probe, |
576 |
raw_open, |
577 |
raw_read, |
578 |
raw_write, |
579 |
raw_close, |
580 |
raw_create, |
581 |
}; |
582 |
|
583 |
void bdrv_init(void) |
584 |
{ |
585 |
bdrv_register(&bdrv_raw); |
586 |
#ifndef _WIN32
|
587 |
bdrv_register(&bdrv_cow); |
588 |
#endif
|
589 |
bdrv_register(&bdrv_qcow); |
590 |
bdrv_register(&bdrv_vmdk); |
591 |
} |