block: add bdrv_write_zeroes()

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Peter Lieven 2013-07-11 14:16:22 +02:00 committed by Stefan Hajnoczi
parent 78f27bd02c
commit 4105eaaab9
2 changed files with 21 additions and 8 deletions

27
block.c
View file

@ -2162,6 +2162,7 @@ typedef struct RwCo {
QEMUIOVector *qiov;
bool is_write;
int ret;
BdrvRequestFlags flags;
} RwCo;
static void coroutine_fn bdrv_rw_co_entry(void *opaque)
@ -2170,10 +2171,12 @@ static void coroutine_fn bdrv_rw_co_entry(void *opaque)
if (!rwco->is_write) {
rwco->ret = bdrv_co_do_readv(rwco->bs, rwco->sector_num,
rwco->nb_sectors, rwco->qiov, 0);
rwco->nb_sectors, rwco->qiov,
rwco->flags);
} else {
rwco->ret = bdrv_co_do_writev(rwco->bs, rwco->sector_num,
rwco->nb_sectors, rwco->qiov, 0);
rwco->nb_sectors, rwco->qiov,
rwco->flags);
}
}
@ -2181,7 +2184,8 @@ static void coroutine_fn bdrv_rw_co_entry(void *opaque)
* Process a vectored synchronous request using coroutines
*/
static int bdrv_rwv_co(BlockDriverState *bs, int64_t sector_num,
QEMUIOVector *qiov, bool is_write)
QEMUIOVector *qiov, bool is_write,
BdrvRequestFlags flags)
{
Coroutine *co;
RwCo rwco = {
@ -2191,6 +2195,7 @@ static int bdrv_rwv_co(BlockDriverState *bs, int64_t sector_num,
.qiov = qiov,
.is_write = is_write,
.ret = NOT_DONE,
.flags = flags,
};
assert((qiov->size & (BDRV_SECTOR_SIZE - 1)) == 0);
@ -2222,7 +2227,7 @@ static int bdrv_rwv_co(BlockDriverState *bs, int64_t sector_num,
* Process a synchronous request using coroutines
*/
static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf,
int nb_sectors, bool is_write)
int nb_sectors, bool is_write, BdrvRequestFlags flags)
{
QEMUIOVector qiov;
struct iovec iov = {
@ -2231,14 +2236,14 @@ static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf,
};
qemu_iovec_init_external(&qiov, &iov, 1);
return bdrv_rwv_co(bs, sector_num, &qiov, is_write);
return bdrv_rwv_co(bs, sector_num, &qiov, is_write, flags);
}
/* return < 0 if error. See bdrv_write() for the return codes */
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false);
return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false, 0);
}
/* Just like bdrv_read(), but with I/O throttling temporarily disabled */
@ -2264,12 +2269,18 @@ int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true);
return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true, 0);
}
int bdrv_writev(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov)
{
return bdrv_rwv_co(bs, sector_num, qiov, true);
return bdrv_rwv_co(bs, sector_num, qiov, true, 0);
}
int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num, int nb_sectors)
{
return bdrv_rw_co(bs, sector_num, NULL, nb_sectors, true,
BDRV_REQ_ZERO_WRITE);
}
int bdrv_pread(BlockDriverState *bs, int64_t offset,

View file

@ -157,6 +157,8 @@ int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors);
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors);
int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
int nb_sectors);
int bdrv_writev(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov);
int bdrv_pread(BlockDriverState *bs, int64_t offset,
void *buf, int count);