Re: [Qemu-devel] [RFC PATCH 5/5] qemu_aio_get used to clear all allocated buffer

[Kevin Wolf <kwolf@redhat.com>]

Am 20.07.2011 09:57, schrieb Frediano Ziglio:
> Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
> ---
>  block/qcow.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/block/qcow.c b/block/qcow.c
> index 007fb57..8fd1ee5 100644
> --- a/block/qcow.c
> +++ b/block/qcow.c
> @@ -499,7 +499,6 @@ static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs,
>          int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
>          int is_write, QCowAIOCB *acb)
>  {
> -    memset(acb, 0, sizeof(*acb));
>      acb->bs = bs;
>      acb->sector_num = sector_num;
>      acb->qiov = qiov;
> @@ -509,6 +508,7 @@ static QCowAIOCB *qcow_aio_setup(BlockDriverState *bs,
>          if (is_write)
>              qemu_iovec_to_buffer(qiov, acb->buf);
>      } else {
> +        acb->orig_buf = NULL;
>          acb->buf = (uint8_t *)qiov->iov->iov_base;
>      }
>      acb->nb_sectors = nb_sectors;

What does this fix? Removing the memset looks like changing code for no
obvious reason. Is there any state in acb that must survive qcow_aio_setup?

Kevin