Re: [Qemu-devel] [PATCH 7/8] block: change flush to co_flush

[Kevin Wolf <kwolf@redhat.com>]

Am 19.10.2011 16:59, schrieb Paolo Bonzini:
> Since coroutine operation is now mandatory, convert all bdrv_flush
> implementations to coroutines.  For qcow2, this means taking the lock.
> Other implementations are simpler and just forward bdrv_flush to the
> underlying protocol, so they can avoid the lock.
> 
> The bdrv_flush callback is then unused and can be eliminated.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

> diff --git a/block/qcow.c b/block/qcow.c
> index f93e3eb..61f73d6 100644
> --- a/block/qcow.c
> +++ b/block/qcow.c
> @@ -781,10 +781,9 @@ static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
>      return 0;
>  }
>  
> -static BlockDriverAIOCB *qcow_aio_flush(BlockDriverState *bs,
> -        BlockDriverCompletionFunc *cb, void *opaque)
> +static coroutine_fn int qcow_co_flush(BlockDriverState *bs)
>  {
> -    return bdrv_aio_flush(bs->file, cb, opaque);
> +    return bdrv_co_flush(bs->file);
>  }
>  
>  static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
> @@ -824,9 +823,9 @@ static BlockDriver bdrv_qcow = {
>      .bdrv_is_allocated	= qcow_is_allocated,
>      .bdrv_set_key	= qcow_set_key,
>      .bdrv_make_empty	= qcow_make_empty,
> -    .bdrv_co_readv  = qcow_co_readv,
> -    .bdrv_co_writev = qcow_co_writev,
> -    .bdrv_aio_flush	= qcow_aio_flush,
> +    .bdrv_co_readv      = qcow_co_readv,
> +    .bdrv_co_writev     = qcow_co_writev,
> +    .bdrv_co_flush	= qcow_co_flush,
>      .bdrv_write_compressed = qcow_write_compressed,
>      .bdrv_get_info	= qcow_get_info,

Please don't add new tabs, use spaces instead. (Same thing in other drivers)

The logic looks good to me.

Kevin