[PATCH v1 02/20] iommu: Introduce a test_dev domain op and an internal helper

[Nicolin Chen]

On Sun, Oct 12, 2025 at 05:04:59PM -0700, Nicolin Chen wrote:
> @@ -3479,38 +3545,19 @@ int iommu_attach_device_pasid(struct iommu_domain *domain,
...
> -	for_each_group_device(group, device) {
> -		/*
> -		 * Skip PASID validation for devices without PASID support
> -		 * (max_pasids = 0). These devices cannot issue transactions
> -		 * with PASID, so they don't affect group's PASID usage.
> -		 */
> -		if ((device->dev->iommu->max_pasids > 0) &&
> -		    (pasid >= device->dev->iommu->max_pasids)) {
> -			ret = -EINVAL;
> -			goto out_unlock;
> -		}
> -	}
> +
> +	ret = __iommu_domain_test_device(domain, dev, pasid, NULL);

I realized that here it needs to be under for_each_group_device,
as its following __iommu_set_group_pasid() calls attach_dev() on
every group_device. So, the new code should run a test_dev() on
every group_device to keep the consistency.

> @@ -3615,6 +3657,11 @@ int iommu_replace_device_pasid(struct iommu_domain *domain,
>  	ret = 0;
>  
>  	if (curr_domain != domain) {
> +		ret = __iommu_domain_test_device(domain, dev, pasid,
> +						 curr_domain);
> +		if (ret)
> +			goto out_unlock;
> +
>  		ret = __iommu_set_group_pasid(domain, group,
>  					      pasid, curr_domain);

Needs the same fix above.

Nicolin