[PATCH v5 09/29] iommufd: Do not unmap an owned iopt_area

[Tian, Kevin]

> From: Nicolin Chen <nicolinc at nvidia.com>
> Sent: Sunday, May 18, 2025 11:21 AM
> 
> @@ -48,6 +48,7 @@ struct iopt_area {
>  	int iommu_prot;
>  	bool prevent_access : 1;
>  	unsigned int num_accesses;
> +	unsigned int num_owners;

What about 'num_locked' to directly mark out that this area
is locked hence cannot be removed? 

Reviewed-by: Kevin Tian <kevin.tian at intel.com>