Revision 51762288 block.c
| b/block.c | ||
|---|---|---|
| 352 | 352 |
return drv; |
| 353 | 353 |
} |
| 354 | 354 |
|
| 355 |
/** |
|
| 356 |
* Set the current 'total_sectors' value |
|
| 357 |
*/ |
|
| 358 |
static int refresh_total_sectors(BlockDriverState *bs, int64_t hint) |
|
| 359 |
{
|
|
| 360 |
BlockDriver *drv = bs->drv; |
|
| 361 |
|
|
| 362 |
/* query actual device if possible, otherwise just trust the hint */ |
|
| 363 |
if (drv->bdrv_getlength) {
|
|
| 364 |
int64_t length = drv->bdrv_getlength(bs); |
|
| 365 |
if (length < 0) {
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|
| 366 |
return length; |
|
| 367 |
} |
|
| 368 |
hint = length >> BDRV_SECTOR_BITS; |
|
| 369 |
} |
|
| 370 |
|
|
| 371 |
bs->total_sectors = hint; |
|
| 372 |
return 0; |
|
| 373 |
} |
|
| 374 |
|
|
| 355 | 375 |
/* |
| 356 | 376 |
* Common part for opening disk images and files |
| 357 | 377 |
*/ |
| ... | ... | |
| 363 | 383 |
assert(drv != NULL); |
| 364 | 384 |
|
| 365 | 385 |
bs->file = NULL; |
| 386 |
bs->total_sectors = 0; |
|
| 366 | 387 |
bs->is_temporary = 0; |
| 367 | 388 |
bs->encrypted = 0; |
| 368 | 389 |
bs->valid_key = 0; |
| ... | ... | |
| 416 | 437 |
} |
| 417 | 438 |
|
| 418 | 439 |
bs->keep_read_only = bs->read_only = !(open_flags & BDRV_O_RDWR); |
| 419 |
if (drv->bdrv_getlength) {
|
|
| 420 |
bs->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS; |
|
| 440 |
|
|
| 441 |
ret = refresh_total_sectors(bs, bs->total_sectors); |
|
| 442 |
if (ret < 0) {
|
|
| 443 |
goto free_and_fail; |
|
| 421 | 444 |
} |
| 445 |
|
|
| 422 | 446 |
#ifndef _WIN32 |
| 423 | 447 |
if (bs->is_temporary) {
|
| 424 | 448 |
unlink(filename); |
| ... | ... | |
| 959 | 983 |
int bdrv_truncate(BlockDriverState *bs, int64_t offset) |
| 960 | 984 |
{
|
| 961 | 985 |
BlockDriver *drv = bs->drv; |
| 986 |
int ret; |
|
| 962 | 987 |
if (!drv) |
| 963 | 988 |
return -ENOMEDIUM; |
| 964 | 989 |
if (!drv->bdrv_truncate) |
| 965 | 990 |
return -ENOTSUP; |
| 966 | 991 |
if (bs->read_only) |
| 967 | 992 |
return -EACCES; |
| 968 |
return drv->bdrv_truncate(bs, offset); |
|
| 993 |
ret = drv->bdrv_truncate(bs, offset); |
|
| 994 |
if (ret == 0) {
|
|
| 995 |
ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS); |
|
| 996 |
} |
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| 997 |
return ret; |
|
| 969 | 998 |
} |
| 970 | 999 |
|
| 971 | 1000 |
/** |
| ... | ... | |
| 976 | 1005 |
BlockDriver *drv = bs->drv; |
| 977 | 1006 |
if (!drv) |
| 978 | 1007 |
return -ENOMEDIUM; |
| 979 |
if (!drv->bdrv_getlength) {
|
|
| 980 |
/* legacy mode */ |
|
| 1008 |
|
|
| 1009 |
/* Fixed size devices use the total_sectors value for speed instead of |
|
| 1010 |
issuing a length query (like lseek) on each call. Also, legacy block |
|
| 1011 |
drivers don't provide a bdrv_getlength function and must use |
|
| 1012 |
total_sectors. */ |
|
| 1013 |
if (!bs->growable || !drv->bdrv_getlength) {
|
|
| 981 | 1014 |
return bs->total_sectors * BDRV_SECTOR_SIZE; |
| 982 | 1015 |
} |
| 983 | 1016 |
return drv->bdrv_getlength(bs); |
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