Re: [RFC V1 01/13] vhost-vdpa: count pinned memory

[Michael S. Tsirkin]

On Wed, Jan 10, 2024 at 12:40:03PM -0800, Steve Sistare wrote:
> Remember the count of pinned memory for the device.
> 
> Signed-off-by: Steve Sistare <steven.sistare@xxxxxxxxxx>

Can we have iommufd support in vdpa so we do not keep extending these hacks?


> ---
>  drivers/vhost/vdpa.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index da7ec77cdaff..10fb95bcca1a 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -59,6 +59,7 @@ struct vhost_vdpa {
>  	int in_batch;
>  	struct vdpa_iova_range range;
>  	u32 batch_asid;
> +	long pinned_vm;
>  };
>  
>  static DEFINE_IDA(vhost_vdpa_ida);
> @@ -893,6 +894,7 @@ static void vhost_vdpa_pa_unmap(struct vhost_vdpa *v, struct vhost_iotlb *iotlb,
>  			unpin_user_page(page);
>  		}
>  		atomic64_sub(PFN_DOWN(map->size), &dev->mm->pinned_vm);
> +		v->pinned_vm -= PFN_DOWN(map->size);
>  		vhost_vdpa_general_unmap(v, map, asid);
>  		vhost_iotlb_map_free(iotlb, map);
>  	}
> @@ -975,9 +977,10 @@ static int vhost_vdpa_map(struct vhost_vdpa *v, struct vhost_iotlb *iotlb,
>  		return r;
>  	}
>  
> -	if (!vdpa->use_va)
> +	if (!vdpa->use_va) {
>  		atomic64_add(PFN_DOWN(size), &dev->mm->pinned_vm);
> -
> +		v->pinned_vm += PFN_DOWN(size);
> +	}
>  	return 0;
>  }
>  
> -- 
> 2.39.3