[PATCH 03/14] iommu: Create a base struct for io_mm

[Jean-Philippe Brucker]

Hi Jordan,

Thank you for this, SMMUv3 and virtio-iommu need these SVA patches as well.

On 21/02/18 22:59, Jordan Crouse wrote:
[...]> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index e2c49e583d8d..e998389cf195 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -110,8 +110,17 @@ struct iommu_domain {
>  	struct list_head mm_list;
>  };
>  
> +enum iommu_io_type {
> +	IO_TYPE_MM,
> +};
> +
> +struct io_base {
> +	int type;
> +	int pasid;
> +};

"io_base" is a bit vague. I'm bad at naming so my opinion doesn't hold
much water, but I'd rather this be something like "io_mm_base". When I
initially toyed with the idea I intended to keep io_mm as parent structure
and have "private" and "shared" sub-structures. Even if private PASIDs
don't rely on the kernel mm subsystem, this structure would still
represent an I/O mm of sorts, with a pgd and pgtable info.

Thanks,
Jean

> +
>  struct io_mm {
> -	int			pasid;
> +	struct io_base		base;
>  	struct list_head	devices;
>  	struct kref		kref;
>  #if defined(CONFIG_MMU_NOTIFIER)
>