Re: [PATCH Kernel v22 7/8] vfio iommu: Add migration capability to report supported features

[Cornelia Huck]

On Mon, 18 May 2020 11:26:36 +0530
Kirti Wankhede <address@hidden> wrote:

> Added migration capability in IOMMU info chain.
> User application should check IOMMU info chain for migration capability
> to use dirty page tracking feature provided by kernel module.
> User application must check page sizes supported and maximum dirty
> bitmap size returned by this capability structure for ioctls used to get
> dirty bitmap.
> 
> Signed-off-by: Kirti Wankhede <address@hidden>
> ---
>  drivers/vfio/vfio_iommu_type1.c | 23 ++++++++++++++++++++++-
>  include/uapi/linux/vfio.h       | 22 ++++++++++++++++++++++
>  2 files changed, 44 insertions(+), 1 deletion(-)

(...)

> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
> index a1dd2150971e..aa8aa9dcf02a 100644
> --- a/include/uapi/linux/vfio.h
> +++ b/include/uapi/linux/vfio.h
> @@ -1013,6 +1013,28 @@ struct vfio_iommu_type1_info_cap_iova_range {
>       struct  vfio_iova_range iova_ranges[];
>  };
>  
> +/*
> + * The migration capability allows to report supported features for 
> migration.
> + *
> + * The structures below define version 1 of this capability.
> + *
> + * The existence of this capability indicates IOMMU kernel driver supports

s/indicates/indicates that/

> + * dirty page tracking.
> + *
> + * pgsize_bitmap: Kernel driver returns supported page sizes bitmap for dirty
> + * page tracking.

"bitmap of supported page sizes for dirty page tracking" ?

> + * max_dirty_bitmap_size: Kernel driver returns maximum supported dirty 
> bitmap
> + * size in bytes to be used by user application for ioctls to get dirty 
> bitmap.

"maximum supported dirty bitmap size in bytes that can be used by user
applications when getting the dirty bitmap" ?

> + */
> +#define VFIO_IOMMU_TYPE1_INFO_CAP_MIGRATION  1
> +
> +struct vfio_iommu_type1_info_cap_migration {
> +     struct  vfio_info_cap_header header;
> +     __u32   flags;
> +     __u64   pgsize_bitmap;
> +     __u64   max_dirty_bitmap_size;          /* in bytes */
> +};
> +
>  #define VFIO_IOMMU_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 12)
>  
>  /**

Reviewed-by: Cornelia Huck <address@hidden>