Re: [PATCH V3 2/4] misc: vop: do not allocate and reassign the used ring

Christoph Hellwig
2020-10-23T09:26:58Z

On Thu, Oct 22, 2020 at 01:06:36PM +0800, Sherry Sun wrote:
> We don't need to allocate and reassign the used ring here and remove the
> used_address_updated flag.Since RC has allocated the entire vring,
> including the used ring. Simply add the corresponding offset can get the
> used ring address.

Someone needs to verify this vs the existing intel implementations.

> - used = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
> - get_order(vdev->used_size[index]));
> + used = va + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +

This adds an over 80 char line.

> + vdev->used[index] = config.address + PAGE_ALIGN(sizeof(struct vring_desc) * le16_to_cpu(config.num) +

Again.