@@ -363,6 +363,7 @@ static int bdrv_open_common(BlockDriverState *bs,
const char *filename,
assert(drv != NULL);
bs->file = NULL;
+ bs->total_sectors = 0;
bs->is_temporary = 0;
bs->encrypted = 0;
bs->valid_key = 0;
@@ -416,9 +417,7 @@ static int bdrv_open_common(BlockDriverState *bs,
const char *filename,
}
bs->keep_read_only = bs->read_only = !(open_flags & BDRV_O_RDWR);
- if (drv->bdrv_getlength) {
- bs->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
- }
+ bs->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
#ifndef _WIN32
if (bs->is_temporary) {
unlink(filename);
@@ -957,13 +956,26 @@ int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
int bdrv_truncate(BlockDriverState *bs, int64_t offset)
{
BlockDriver *drv = bs->drv;
+ int ret;
if (!drv)
return -ENOMEDIUM;
if (!drv->bdrv_truncate)
return -ENOTSUP;
if (bs->read_only)
return -EACCES;
- return drv->bdrv_truncate(bs, offset);
+ ret = drv->bdrv_truncate(bs, offset);
+ if (ret < 0) {
+ return ret;
+ }
+
+ /* refresh total sectors */
+ if (drv->bdrv_getlength) {
+ bs->total_sectors = 0; /* discard cached value */
+ bs->total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+ } else {
+ bs->total_sectors = offset >> BDRV_SECTOR_BITS;
+ }
+ return ret;
}
/**
@@ -974,8 +986,12 @@ int64_t bdrv_getlength(BlockDriverState *bs)
BlockDriver *drv = bs->drv;
if (!drv)
return -ENOMEDIUM;
- if (!drv->bdrv_getlength) {
- /* legacy mode */
+
+ /* Fixed size devices use the total_sectors value for speed instead of
+ issuing a length query (like lseek) on each call. Also, legacy block
+ drivers don't provide a bdrv_getlength function and must use
+ total_sectors. */
+ if ((bs->total_sectors && !bs->growable) || !drv->bdrv_getlength) {
return bs->total_sectors * BDRV_SECTOR_SIZE;
}
return drv->bdrv_getlength(bs);
@@ -105,7 +105,6 @@
typedef struct BDRVRawState {
int fd;
int type;
- unsigned int lseek_err_cnt;
int open_flags;
#if defined(__linux__)
/* linux floppy specific */
@@ -134,8 +133,6 @@ static int raw_open_common(BlockDriverState *bs,
const char *filename,
BDRVRawState *s = bs->opaque;
int fd, ret;
- s->lseek_err_cnt = 0;
-
s->open_flags = open_flags | O_BINARY;
s->open_flags &= ~O_ACCMODE;