RE: [PATCH RFC 06/11] iommu/sva: Use attach/detach_pasid_dev in SVA interfaces

[Tian, Kevin]

> From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Sent: Sunday, March 20, 2022 2:40 PM
> +struct iommu_sva *
> +iommu_sva_bind_device(struct device *dev, struct mm_struct *mm, void
> *drvdata)
> +{
> +	int ret = -EINVAL;
> +	struct iommu_sva *handle;
> +	struct iommu_domain *domain;
> +
> +	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
> +	if (!handle)
> +		return ERR_PTR(-ENOMEM);
> +
> +	ret = iommu_sva_alloc_pasid(mm, 1, (1U << dev->iommu->pasid_bits)
> - 1);
> +	if (ret)
> +		goto out;
> +
> +	domain = iommu_sva_domain_alloc(dev);
> +	if (!domain) {
> +		ret = -ENOMEM;
> +		goto out;
> +	}
> +	domain->sva_cookie = mm;

one domain can be attached by multiple devices, so this should not be
a blind alloc.