Re: [PATCH v2 4/4] vfio/iommufd: Save vendor specific device info

[Nicolin Chen <nicolinc@nvidia.com>]

On Fri, May 30, 2025 at 05:35:12PM +0800, Zhenzhong Duan wrote:
> Some device information returned by ioctl(IOMMU_GET_HW_INFO) are vendor
> specific. Save them as raw data in a union supporting different vendors,
> then vendor IOMMU can query the raw data with its fixed format for
> capability directly.
> 
> Because IOMMU_GET_HW_INFO is only supported in linux, so declare those
> capability related structures with CONFIG_LINUX.
> 
> Suggested-by: Eric Auger <eric.auger@redhat.com>
> Suggested-by: Nicolin Chen <nicolinc@nvidia.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>

Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>

I like this that we eventually moved all vendor stuff back to the
vendor vIOMMU code.

> +typedef union VendorCaps {
> +    struct iommu_hw_info_vtd vtd;
> +    struct iommu_hw_info_arm_smmuv3 smmuv3;
> +} VendorCaps;

Nit: can it be just:

typedef union {
	...
} VendorCaps; 

?

>  typedef struct HostIOMMUDeviceCaps {
>      uint32_t type;
>      uint64_t hw_caps;
> +    VendorCaps vendor_caps;
>  } HostIOMMUDeviceCaps;

Ditto.