Re: [PATCH v3 16/34] iommu/vt-d: Convert to probe/release_device() call-backs

[Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>]

On 2020/4/29 21:36, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@xxxxxxx>
>
> Convert the Intel IOMMU driver to use the probe_device() and
> release_device() call-backs of iommu_ops, so that the iommu core code
> does the group and sysfs setup.
>
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>

Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

Best regards,
baolu

> ---
>   drivers/iommu/intel-iommu.c | 67 ++++---------------------------------
>   1 file changed, 6 insertions(+), 61 deletions(-)
>
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index b9f905a55dda..b906727f5b85 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -5781,78 +5781,27 @@ static bool intel_iommu_capable(enum iommu_cap cap)
>   	return false;
>   }
>   
> -static int intel_iommu_add_device(struct device *dev)
> +static struct iommu_device *intel_iommu_probe_device(struct device *dev)
>   {
> -	struct dmar_domain *dmar_domain;
> -	struct iommu_domain *domain;
>   	struct intel_iommu *iommu;
> -	struct iommu_group *group;
>   	u8 bus, devfn;
> -	int ret;
>   
>   	iommu = device_to_iommu(dev, &bus, &devfn);
>   	if (!iommu)
> -		return -ENODEV;
> -
> -	iommu_device_link(&iommu->iommu, dev);
> +		return ERR_PTR(-ENODEV);
>   
>   	if (translation_pre_enabled(iommu))
>   		dev->archdata.iommu = DEFER_DEVICE_DOMAIN_INFO;
>   
> -	group = iommu_group_get_for_dev(dev);
> -
> -	if (IS_ERR(group)) {
> -		ret = PTR_ERR(group);
> -		goto unlink;
> -	}
> -
> -	iommu_group_put(group);
> -
> -	domain = iommu_get_domain_for_dev(dev);
> -	dmar_domain = to_dmar_domain(domain);
> -	if (domain->type == IOMMU_DOMAIN_DMA) {
> -		if (device_def_domain_type(dev) == IOMMU_DOMAIN_IDENTITY) {
> -			ret = iommu_request_dm_for_dev(dev);
> -			if (ret) {
> -				dmar_remove_one_dev_info(dev);
> -				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
> -				domain_add_dev_info(si_domain, dev);
> -				dev_info(dev,
> -					 "Device uses a private identity domain.\n");
> -			}
> -		}
> -	} else {
> -		if (device_def_domain_type(dev) == IOMMU_DOMAIN_DMA) {
> -			ret = iommu_request_dma_domain_for_dev(dev);
> -			if (ret) {
> -				dmar_remove_one_dev_info(dev);
> -				dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
> -				if (!get_private_domain_for_dev(dev)) {
> -					dev_warn(dev,
> -						 "Failed to get a private domain.\n");
> -					ret = -ENOMEM;
> -					goto unlink;
> -				}
> -
> -				dev_info(dev,
> -					 "Device uses a private dma domain.\n");
> -			}
> -		}
> -	}
> -
>   	if (device_needs_bounce(dev)) {
>   		dev_info(dev, "Use Intel IOMMU bounce page dma_ops\n");
>   		set_dma_ops(dev, &bounce_dma_ops);
>   	}
>   
> -	return 0;
> -
> -unlink:
> -	iommu_device_unlink(&iommu->iommu, dev);
> -	return ret;
> +	return &iommu->iommu;
>   }
>   
> -static void intel_iommu_remove_device(struct device *dev)
> +static void intel_iommu_release_device(struct device *dev)
>   {
>   	struct intel_iommu *iommu;
>   	u8 bus, devfn;
> @@ -5863,10 +5812,6 @@ static void intel_iommu_remove_device(struct device *dev)
>   
>   	dmar_remove_one_dev_info(dev);
>   
> -	iommu_group_remove_device(dev);
> -
> -	iommu_device_unlink(&iommu->iommu, dev);
> -
>   	if (device_needs_bounce(dev))
>   		set_dma_ops(dev, NULL);
>   }
> @@ -6198,8 +6143,8 @@ const struct iommu_ops intel_iommu_ops = {
>   	.map			= intel_iommu_map,
>   	.unmap			= intel_iommu_unmap,
>   	.iova_to_phys		= intel_iommu_iova_to_phys,
> -	.add_device		= intel_iommu_add_device,
> -	.remove_device		= intel_iommu_remove_device,
> +	.probe_device		= intel_iommu_probe_device,
> +	.release_device		= intel_iommu_release_device,
>   	.get_resv_regions	= intel_iommu_get_resv_regions,
>   	.put_resv_regions	= generic_iommu_put_resv_regions,
>   	.apply_resv_region	= intel_iommu_apply_resv_region,