Subject: Re: [PATCH 02/13] iommu/vt-d: Use dev_iommu_priv_get/set()

From: Lu Baolu <[email-masked]>
Date: Thu, 25 Jun 2020 21:24:00 +0800

Hi Joerg,

On 2020/6/25 21:08, Joerg Roedel wrote:
> From: Joerg Roedel <[email-masked]>
> 
> Remove the use of dev->archdata.iommu and use the private per-device
> pointer provided by IOMMU core code instead.
> 
> Signed-off-by: Joerg Roedel <[email-masked]>
> ---
>   .../gpu/drm/i915/selftests/mock_gem_device.c   | 10 ++++++++--
>   drivers/iommu/intel/iommu.c                    | 18 +++++++++---------

For changes in VT-d driver,

Reviewed-by: Lu Baolu <[email-masked]>

Best regards,
baolu

>   2 files changed, 17 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/selftests/mock_gem_device.c b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
> index 9b105b811f1f..e08601905a64 100644
> --- a/drivers/gpu/drm/i915/selftests/mock_gem_device.c
> +++ b/drivers/gpu/drm/i915/selftests/mock_gem_device.c
> @@ -24,6 +24,7 @@
>   
>   #include <linux/pm_domain.h>
>   #include <linux/pm_runtime.h>
> +#include <linux/iommu.h>
>   
>   #include <drm/drm_managed.h>
>   
> @@ -118,6 +119,9 @@ struct drm_i915_private *mock_gem_device(void)
>   {
>   	struct drm_i915_private *i915;
>   	struct pci_dev *pdev;
> +#if IS_ENABLED(CONFIG_IOMMU_API) && defined(CONFIG_INTEL_IOMMU)
> +	struct dev_iommu iommu;
> +#endif
>   	int err;
>   
>   	pdev = kzalloc(sizeof(*pdev), GFP_KERNEL);
> @@ -136,8 +140,10 @@ struct drm_i915_private *mock_gem_device(void)
>   	dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
>   
>   #if IS_ENABLED(CONFIG_IOMMU_API) && defined(CONFIG_INTEL_IOMMU)
> -	/* hack to disable iommu for the fake device; force identity mapping */
> -	pdev->dev.archdata.iommu = (void *)-1;
> +	/* HACK HACK HACK to disable iommu for the fake device; force identity mapping */
> +	memset(&iommu, 0, sizeof(iommu));
> +	iommu.priv = (void *)-1;
> +	pdev->dev.iommu = &iommu;
>   #endif
>   
>   	pci_set_drvdata(pdev, i915);
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index d759e7234e98..2ce490c2eab8 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -372,7 +372,7 @@ struct device_domain_info *get_domain_info(struct device *dev)
>   	if (!dev)
>   		return NULL;
>   
> -	info = dev->archdata.iommu;
> +	info = dev_iommu_priv_get(dev);
>   	if (unlikely(info == DUMMY_DEVICE_DOMAIN_INFO ||
>   		     info == DEFER_DEVICE_DOMAIN_INFO))
>   		return NULL;
> @@ -743,12 +743,12 @@ struct context_entry *iommu_context_addr(struct intel_iommu *iommu, u8 bus,
>   
>   static int iommu_dummy(struct device *dev)
>   {
> -	return dev->archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO;
> +	return dev_iommu_priv_get(dev) == DUMMY_DEVICE_DOMAIN_INFO;
>   }
>   
>   static bool attach_deferred(struct device *dev)
>   {
> -	return dev->archdata.iommu == DEFER_DEVICE_DOMAIN_INFO;
> +	return dev_iommu_priv_get(dev) == DEFER_DEVICE_DOMAIN_INFO;
>   }
>   
>   /**
> @@ -2420,7 +2420,7 @@ static inline void unlink_domain_info(struct device_domain_info *info)
>   	list_del(&info->link);
>   	list_del(&info->global);
>   	if (info->dev)
> -		info->dev->archdata.iommu = NULL;
> +		dev_iommu_priv_set(info->dev, NULL);
>   }
>   
>   static void domain_remove_dev_info(struct dmar_domain *domain)
> @@ -2453,7 +2453,7 @@ static void do_deferred_attach(struct device *dev)
>   {
>   	struct iommu_domain *domain;
>   
> -	dev->archdata.iommu = NULL;
> +	dev_iommu_priv_set(dev, NULL);
>   	domain = iommu_get_domain_for_dev(dev);
>   	if (domain)
>   		intel_iommu_attach_device(domain, dev);
> @@ -2599,7 +2599,7 @@ static struct dmar_domain *dmar_insert_one_dev_info(struct intel_iommu *iommu,
>   	list_add(&info->link, &domain->devices);
>   	list_add(&info->global, &device_domain_list);
>   	if (dev)
> -		dev->archdata.iommu = info;
> +		dev_iommu_priv_set(dev, info);
>   	spin_unlock_irqrestore(&device_domain_lock, flags);
>   
>   	/* PASID table is mandatory for a PCI device in scalable mode. */
> @@ -4004,7 +4004,7 @@ static void quirk_ioat_snb_local_iommu(struct pci_dev *pdev)
>   	if (!drhd || drhd->reg_base_addr - vtbar != 0xa000) {
>   		pr_warn_once(FW_BUG "BIOS assigned incorrect VT-d unit for Intel(R) QuickData Technology device\n");
>   		add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
> -		pdev->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
> +		dev_iommu_priv_set(&pdev->dev, DUMMY_DEVICE_DOMAIN_INFO);
>   	}
>   }
>   DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_IOAT_SNB, quirk_ioat_snb_local_iommu);
> @@ -4043,7 +4043,7 @@ static void __init init_no_remapping_devices(void)
>   			drhd->ignored = 1;
>   			for_each_active_dev_scope(drhd->devices,
>   						  drhd->devices_cnt, i, dev)
> -				dev->archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
> +				dev_iommu_priv_set(dev, DUMMY_DEVICE_DOMAIN_INFO);
>   		}
>   	}
>   }
> @@ -5665,7 +5665,7 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev)
>   		return ERR_PTR(-ENODEV);
>   
>   	if (translation_pre_enabled(iommu))
> -		dev->archdata.iommu = DEFER_DEVICE_DOMAIN_INFO;
> +		dev_iommu_priv_set(dev, DEFER_DEVICE_DOMAIN_INFO);
>   
>   	return &iommu->iommu;
>   }
>