Re: [PATCH v6 02/10] iommu: Pass in parent domain with user_data to domain_alloc_user op

[Jason Gunthorpe]

On Tue, Oct 24, 2023 at 08:06:01AM -0700, Yi Liu wrote:
> domain_alloc_user op already accepts user flags for domain allocation, add
> a parent domain pointer and a driver specific user data support as well.
> 
> Add a struct iommu_user_data as a bundle of data_ptr/data_len/type from an
> iommufd core uAPI structure. Make the user data opaque to the core, since
> a userspace driver must match the kernel driver. In the future, if drivers
> share some common parameter, there would be a generic parameter as well.
> 
> Define an enum iommu_hwpt_data_type (with IOMMU_HWPT_DATA_NONE type) for
> iommu drivers to add their own driver specific user data per hw_pagetable.
> 
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Co-developed-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
> ---
>  drivers/iommu/intel/iommu.c          |  7 ++++++-
>  drivers/iommu/iommufd/hw_pagetable.c |  3 ++-
>  drivers/iommu/iommufd/selftest.c     |  7 ++++++-
>  include/linux/iommu.h                | 27 ++++++++++++++++++++++++---
>  include/uapi/linux/iommufd.h         |  8 ++++++++
>  5 files changed, 46 insertions(+), 6 deletions(-)

This patch should be immediately before "iommufd: Add a nested HW
pagetable object"

Since it is basically preperation for that patch

> diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
> index c44eecf5d318..fccc6315a520 100644
> --- a/include/uapi/linux/iommufd.h
> +++ b/include/uapi/linux/iommufd.h
> @@ -361,6 +361,14 @@ enum iommufd_hwpt_alloc_flags {
>  	IOMMU_HWPT_ALLOC_DIRTY_TRACKING = 1 << 1,
>  };
>  
> +/**
> + * enum iommu_hwpt_data_type - IOMMU HWPT Data Type
> + * @IOMMU_HWPT_DATA_NONE: no data
> + */
> +enum iommu_hwpt_data_type {
> +	IOMMU_HWPT_DATA_NONE,
> +};
> +

And this hunk should go in "iommufd: Add a nested HW pagetable object"

With the rest of the uapi

Jason