Re: [RFC v1 6/8] vdpa: change the map/unmap process to support iommufd

[Yi Liu]

On 2023/11/4 01:16, Cindy Lu wrote:
> Add the check for iommufd_ictx,If vdpa don't have the iommufd_ictx
> then will use the Legacy iommu domain pathway
>
> Signed-off-by: Cindy Lu <lulu@xxxxxxxxxx>
> ---
>   drivers/vhost/vdpa.c | 43 ++++++++++++++++++++++++++++++++++++++-----
>   1 file changed, 38 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index dfaddd833364..0e2dba59e1ce 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -1067,9 +1067,6 @@ static int vhost_vdpa_map(struct vhost_vdpa *v, struct vhost_iotlb *iotlb,
>   		/* Legacy iommu domain pathway without IOMMUFD */
>   		r = iommu_map(v->domain, iova, pa, size,
>   			      perm_to_iommu_flags(perm), GFP_KERNEL);
> -	} else {
> -		r = iommu_map(v->domain, iova, pa, size,
> -			      perm_to_iommu_flags(perm), GFP_KERNEL);
>   	}
>   	if (r) {
>   		vhost_iotlb_del_range(iotlb, iova, iova + size - 1);
> @@ -1095,8 +1092,10 @@ static void vhost_vdpa_unmap(struct vhost_vdpa *v,
>   	if (ops->set_map) {
>   		if (!v->in_batch)
>   			ops->set_map(vdpa, asid, iotlb);
> +	} else if (!vdpa->iommufd_ictx) {
> +		/* Legacy iommu domain pathway without IOMMUFD */
> +		iommu_unmap(v->domain, iova, size);
>   	}
> -
>   }
>   
>   static int vhost_vdpa_va_map(struct vhost_vdpa *v,
> @@ -1149,7 +1148,36 @@ static int vhost_vdpa_va_map(struct vhost_vdpa *v,
>   
>   	return ret;
>   }
> +#if 0
> +int vhost_pin_pages(struct vdpa_device *device, dma_addr_t iova, int npage,
> +		    int prot, struct page **pages)
> +{
> +	if (!pages || !npage)
> +		return -EINVAL;
> +	//if (!device->config->dma_unmap)
> +	//return -EINVAL;
> +
> +	if (0) { //device->iommufd_access) {
> +		int ret;
> +
> +		if (iova > ULONG_MAX)
> +			return -EINVAL;
>   
> +		ret = iommufd_access_pin_pages(
> +			device->iommufd_access, iova, npage * PAGE_SIZE, pages,
> +			(prot & IOMMU_WRITE) ? IOMMUFD_ACCESS_RW_WRITE : 0);
> +		if (ret) {
> +
> +			return ret;
> +		}
> +
> +		return npage;
> +	} else {
> +		return pin_user_pages(iova, npage, prot, pages);
> +	}
> +	return -EINVAL;
> +}
> +#endif

Is above code needed or not?

>   static int vhost_vdpa_pa_map(struct vhost_vdpa *v,
>   			     struct vhost_iotlb *iotlb,
>   			     u64 iova, u64 size, u64 uaddr, u32 perm)
> @@ -1418,9 +1446,13 @@ static void vhost_vdpa_free_domain(struct vhost_vdpa *v)
>   	struct device *dma_dev = vdpa_get_dma_dev(vdpa);
>   
>   	if (v->domain) {
> -		iommu_detach_device(v->domain, dma_dev);
> +		if (!vdpa->iommufd_ictx) {
> +			iommu_detach_device(v->domain, dma_dev);
> +		}
>   		iommu_domain_free(v->domain);
>   	}
> +	if (vdpa->iommufd_ictx)
> +		vdpa_iommufd_unbind(vdpa);
>   
>   	v->domain = NULL;
>   }
> @@ -1645,6 +1677,7 @@ static int vhost_vdpa_probe(struct vdpa_device *vdpa)
>   	}
>   
>   	atomic_set(&v->opened, 0);
> +	atomic_set(&vdpa->iommufd_users, 0);
>   	v->minor = minor;
>   	v->vdpa = vdpa;
>   	v->nvqs = vdpa->nvqs;

--
Regards,
Yi Liu