Re: [PATCH rfcv2 06/20] host_iommu_device: Define two new capabilities HOST_IOMMU_DEVICE_CAP_[NESTING|FS1GP]

[Eric Auger <eric.auger@redhat.com>]

Hi Zhenzhong,


On 2/19/25 9:22 AM, Zhenzhong Duan wrote:
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
> ---
>  include/system/host_iommu_device.h | 8 ++++++++
>  1 file changed, 8 insertions(+)
>
> diff --git a/include/system/host_iommu_device.h b/include/system/host_iommu_device.h
> index df782598f2..18f8b5e5cf 100644
> --- a/include/system/host_iommu_device.h
> +++ b/include/system/host_iommu_device.h
> @@ -22,10 +22,16 @@
>   *
>   * @hw_caps: host platform IOMMU capabilities (e.g. on IOMMUFD this represents
>   *           the @out_capabilities value returned from IOMMU_GET_HW_INFO ioctl)
> + *
> + * @nesting: nesting page table support.
> + *
> + * @fs1gp: first stage(a.k.a, Stage-1) 1GB huge page support.
>   */
>  typedef struct HostIOMMUDeviceCaps {
>      uint32_t type;
>      uint64_t hw_caps;
> +    bool nesting;
> +    bool fs1gp;
this looks quite vtd specific, isn't it? Shouldn't we hide this is a
vendor specific cap struct?
>  } HostIOMMUDeviceCaps;
>  
>  #define TYPE_HOST_IOMMU_DEVICE "host-iommu-device"
> @@ -122,6 +128,8 @@ struct HostIOMMUDeviceClass {
>   */
>  #define HOST_IOMMU_DEVICE_CAP_IOMMU_TYPE        0
>  #define HOST_IOMMU_DEVICE_CAP_AW_BITS           1
> +#define HOST_IOMMU_DEVICE_CAP_NESTING           2
> +#define HOST_IOMMU_DEVICE_CAP_FS1GP             3
>  
>  #define HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX       64
>  #endif

Maybe you could introduce the associated implementation of
hiod_iommufd_get_cap in this patch too?

Eric