Re: [PATCH 3/9] iommu/generic_pt: implement iova_to_phys_length

[Jason Gunthorpe]

On Sun, May 31, 2026 at 05:36:31PM +0800, Guanghui Feng wrote:
> @@ -159,45 +164,51 @@ static __always_inline int __do_iova_to_phys(struct pt_range *range, void *arg,
>  	case PT_ENTRY_TABLE:
>  		return pt_descend(&pts, arg, descend_fn);
>  	case PT_ENTRY_OA:
> -		*res = pt_entry_oa_exact(&pts);
> +		data->phys = pt_entry_oa_exact(&pts);
> +		data->length = BIT(pt_entry_oa_lg2sz(&pts));

BIT is the wrong function, it uses the wrong type. log2_to_int() is
type'd properly

This also needs to keep walking and accumulating length for
consecutive PTEs until it reaches a non-contiguity.

The other drivers don't need to have that complexity.

Jason