Am 26.07.2011 13:49, schrieb Kevin Wolf:
> In order to be able to call bdrv_co_readv/writev for drivers that don't
> implement the functions natively, add an emulation that uses the AIO functions
> to implement them.
>
> Signed-off-by: Kevin Wolf <kw...@redhat.com>
> ---
> block.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++++-----
> trace-events | 1 +
> 2 files changed, 77 insertions(+), 8 deletions(-)
>
> diff --git a/block.c b/block.c
> index 48413ae..2f589ac 100644
> --- a/block.c
> +++ b/block.c
> @@ -64,6 +64,12 @@ static BlockDriverAIOCB
> *bdrv_co_aio_readv_em(BlockDriverState *bs,
> static BlockDriverAIOCB *bdrv_co_aio_writev_em(BlockDriverState *bs,
> int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
> BlockDriverCompletionFunc *cb, void *opaque);
> +static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
> + int64_t sector_num, int nb_sectors,
> + QEMUIOVector *iov);
> +static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
> + int64_t sector_num, int nb_sectors,
> + QEMUIOVector *iov);
>
> static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
> QTAILQ_HEAD_INITIALIZER(bdrv_states);
> @@ -182,14 +188,19 @@ void bdrv_register(BlockDriver *bdrv)
> bdrv->bdrv_aio_writev = bdrv_co_aio_writev_em;
> bdrv->bdrv_read = bdrv_read_em;
> bdrv->bdrv_write = bdrv_write_em;
> - } else if (!bdrv->bdrv_aio_readv) {
> - /* add AIO emulation layer */
> - bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
> - bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
> - } else if (!bdrv->bdrv_read) {
> - /* add synchronous IO emulation layer */
> - bdrv->bdrv_read = bdrv_read_em;
> - bdrv->bdrv_write = bdrv_write_em;
> + } else {
> + bdrv->bdrv_co_readv = bdrv_co_readv_em;
> + bdrv->bdrv_co_writev = bdrv_co_writev_em;
> +
> + if (!bdrv->bdrv_aio_readv) {
> + /* add AIO emulation layer */
> + bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
> + bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
> + } else if (!bdrv->bdrv_read) {
> + /* add synchronous IO emulation layer */
> + bdrv->bdrv_read = bdrv_read_em;
> + bdrv->bdrv_write = bdrv_write_em;
> + }
> }
>
> if (!bdrv->bdrv_aio_flush)
> @@ -2868,6 +2879,63 @@ void qemu_aio_release(void *p)
> }
>
> /**************************************************************/
> +/* Coroutine block device emulation */
> +
> +typedef struct CoroutineIOCompletion {
> + Coroutine *coroutine;
> + int ret;
> +} CoroutineIOCompletion;
> +
> +static void bdrv_co_io_em_complete(void *opaque, int ret)
> +{
> + CoroutineIOCompletion *co = opaque;
> +
> + co->ret = ret;
> + qemu_coroutine_enter(co->coroutine, NULL);
> +}
> +
> +static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t
> sector_num,
> + int nb_sectors, QEMUIOVector *iov,
> + bool is_write)
> +{
> + CoroutineIOCompletion co = {
> + .coroutine = qemu_coroutine_self(),
> + .ret = -EINPROGRESS,
This line doesn't compile with mingw32. Additionally, we never use this
value, so I just dropped it from the patch in the block queue.
Unless someone insists on it, I won't resend the series for this one-liner.
Kevin
