Received-SPF: pass (google.com: domain of linux-kernel+bounces-22843-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Date: Wed, 10 Jan 2024 17:24:02 -0500
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Steve Sistare <steven.sistare@oracle.com>
Cc: virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
	Jason Wang <jasowang@redhat.com>,
	Si-Wei Liu <si-wei.liu@oracle.com>,
	Eugenio Perez Martin <eperezma@redhat.com>,
	Xuan Zhuo <xuanzhuo@linux.alibaba.com>,
	Dragos Tatulea <dtatulea@nvidia.com>, Eli Cohen <elic@nvidia.com>,
	Xie Yongji <xieyongji@bytedance.com>
Subject: Re: [RFC V1 01/13] vhost-vdpa: count pinned memory
Message-ID: <20240110172306-mutt-send-email-mst@kernel.org>
References: <1704919215-91319-1-git-send-email-steven.sistare@oracle.com>
 <1704919215-91319-2-git-send-email-steven.sistare@oracle.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1704919215-91319-2-git-send-email-steven.sistare@oracle.com>

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@oracle.com>

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