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block: Use bdrv_co_* instead of synchronous versions in coroutines

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If we're already in a coroutine, there is no reason to use the synchronous
version of block layer functions when a coroutine one exists. This makes
bdrv_read/write/flush use bdrv_co_* when used inside a coroutine.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2011-07-15 16:05:00 +02:00
parent ba1d1afdfe
commit e7a8a7837a
1 changed files with 56 additions and 0 deletions
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56
block.c
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@ -70,6 +70,7 @@ static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
int64_t sector_num, int nb_sectors,
QEMUIOVector *iov);
static int coroutine_fn bdrv_co_flush_em(BlockDriverState *bs);
static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
QTAILQ_HEAD_INITIALIZER(bdrv_states);
@ -946,6 +947,17 @@ static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
nb_sectors * BDRV_SECTOR_SIZE);
}
static inline bool bdrv_has_async_rw(BlockDriver *drv)
{
return drv->bdrv_co_readv != bdrv_co_readv_em
|| drv->bdrv_aio_readv != bdrv_aio_readv_em;
}
static inline bool bdrv_has_async_flush(BlockDriver *drv)
{
return drv->bdrv_aio_flush != bdrv_aio_flush_em;
}
/* 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)
@ -954,6 +966,18 @@ int bdrv_read(BlockDriverState *bs, int64_t sector_num,
if (!drv)
return -ENOMEDIUM;
if (bdrv_has_async_rw(drv) && qemu_in_coroutine()) {
QEMUIOVector qiov;
struct iovec iov = {
.iov_base = (void *)buf,
.iov_len = nb_sectors * BDRV_SECTOR_SIZE,
};
qemu_iovec_init_external(&qiov, &iov, 1);
return bdrv_co_readv(bs, sector_num, nb_sectors, &qiov);
}
if (bdrv_check_request(bs, sector_num, nb_sectors))
return -EIO;
@ -998,8 +1022,21 @@ int bdrv_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
BlockDriver *drv = bs->drv;
if (!bs->drv)
return -ENOMEDIUM;
if (bdrv_has_async_rw(drv) && qemu_in_coroutine()) {
QEMUIOVector qiov;
struct iovec iov = {
.iov_base = (void *)buf,
.iov_len = nb_sectors * BDRV_SECTOR_SIZE,
};
qemu_iovec_init_external(&qiov, &iov, 1);
return bdrv_co_writev(bs, sector_num, nb_sectors, &qiov);
}
if (bs->read_only)
return -EACCES;
if (bdrv_check_request(bs, sector_num, nb_sectors))
@ -1649,6 +1686,10 @@ int bdrv_flush(BlockDriverState *bs)
return 0;
}
if (bs->drv && bdrv_has_async_flush(bs->drv) && qemu_in_coroutine()) {
return bdrv_co_flush_em(bs);
}
if (bs->drv && bs->drv->bdrv_flush) {
return bs->drv->bdrv_flush(bs);
}
@ -2916,6 +2957,21 @@ static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true);
}
static int coroutine_fn bdrv_co_flush_em(BlockDriverState *bs)
{
CoroutineIOCompletion co = {
.coroutine = qemu_coroutine_self(),
};
BlockDriverAIOCB *acb;
acb = bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co);
if (!acb) {
return -EIO;
}
qemu_coroutine_yield();
return co.ret;
}
/**************************************************************/
/* removable device support */