On Wed, May 08, 2024 at 02:37:15PM +0800, Xuan Zhuo wrote:
> Now, we have virtio DMA APIs, the driver can be the premapped
> mode whatever the virtio core uses dma api or not.
>
> So remove the limit of checking use_dma_api from
> virtqueue_set_dma_premapped().
>
> Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com>
> Acked-by: Jason Wang <jasow...@redhat.com>
> ---
> drivers/virtio/virtio_ring.c | 7 +------
> 1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 6f7e5010a673..85d0dc26ae9f 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -2782,7 +2782,7 @@ EXPORT_SYMBOL_GPL(virtqueue_resize);
> *
> * Returns zero or a negative error.
> * 0: success.
> - * -EINVAL: vring does not use the dma api, so we can not enable premapped
> mode.
> + * -EINVAL: the vq is in use.
To me it sounds more like -EBUSY with the current error description.
But I suspect that the error is returned, when the following condition is not
met:
* This function must be called immediately after creating the vq, or after vq
* reset, and before adding any buffers to it.
If I am not mistaking, then a better way to put it would be:
* -EINVAL: too late to enable premapped mode, the vq already contains buffers
> */
> int virtqueue_set_dma_premapped(struct virtqueue *_vq)
> {
> @@ -2798,11 +2798,6 @@ int virtqueue_set_dma_premapped(struct virtqueue *_vq)
> return -EINVAL;
> }
>
> - if (!vq->use_dma_api) {
> - END_USE(vq);
> - return -EINVAL;
> - }
> -
> vq->premapped = true;
> vq->do_unmap = false;
>
> --
> 2.32.0.3.g01195cf9f
>
>
