Commit c7be17c2 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Add device_block_translation() helper 



If domain attaching to device fails, the IOMMU driver should bring the
device to blocking DMA state. The upper layer is expected to recover it
by attaching a new domain. Use device_block_translation() in the error
path of dev_attach to make the behavior specific.

The difference between device_block_translation() and the previous
dmar_remove_one_dev_info() is that, in the scalable mode, it is the
RID2PASID entry instead of context entry being cleared. As a result,
enabling PCI capabilities is moved up.

Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20221118132451.114406-3-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent ec62b442

drivers/iommu/intel/iommu.c

+38 −6
Original line number Diff line number Diff line
@@ -277,7 +277,7 @@ static LIST_HEAD(dmar_satc_units); 
#define for_each_rmrr_units(rmrr) \

	list_for_each_entry(rmrr, &dmar_rmrr_units, list)



static void dmar_remove_one_dev_info(struct device *dev);

static void device_block_translation(struct device *dev);



int dmar_disabled = !IS_ENABLED(CONFIG_INTEL_IOMMU_DEFAULT_ON);

int intel_iommu_sm = IS_ENABLED(CONFIG_INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON);
@@ -1400,7 +1400,7 @@ static void iommu_enable_pci_caps(struct device_domain_info *info) 
{

	struct pci_dev *pdev;



	if (!info || !dev_is_pci(info->dev))

	if (!dev_is_pci(info->dev))

		return;



	pdev = to_pci_dev(info->dev);
@@ -2045,7 +2045,6 @@ static int domain_context_mapping_one(struct dmar_domain *domain, 
	} else {

		iommu_flush_write_buffer(iommu);

	}

	iommu_enable_pci_caps(info);



	ret = 0;
@@ -2487,7 +2486,7 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev) 
					dev, PASID_RID2PASID);

		if (ret) {

			dev_err(dev, "Setup RID2PASID failed\n");

			dmar_remove_one_dev_info(dev);

			device_block_translation(dev);

			return ret;

		}

	}
@@ -2495,10 +2494,12 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev) 
	ret = domain_context_mapping(domain, dev);

	if (ret) {

		dev_err(dev, "Domain context map failed\n");

		dmar_remove_one_dev_info(dev);

		device_block_translation(dev);

		return ret;

	}



	iommu_enable_pci_caps(info);



	return 0;

}
@@ -4109,6 +4110,37 @@ static void dmar_remove_one_dev_info(struct device *dev) 
	info->domain = NULL;

}



/*

 * Clear the page table pointer in context or pasid table entries so that

 * all DMA requests without PASID from the device are blocked. If the page

 * table has been set, clean up the data structures.

 */

static void device_block_translation(struct device *dev)

{

	struct device_domain_info *info = dev_iommu_priv_get(dev);

	struct intel_iommu *iommu = info->iommu;

	unsigned long flags;



	iommu_disable_dev_iotlb(info);

	if (!dev_is_real_dma_subdevice(dev)) {

		if (sm_supported(iommu))

			intel_pasid_tear_down_entry(iommu, dev,

						    PASID_RID2PASID, false);

		else

			domain_context_clear(info);

	}



	if (!info->domain)

		return;



	spin_lock_irqsave(&info->domain->lock, flags);

	list_del(&info->link);

	spin_unlock_irqrestore(&info->domain->lock, flags);



	domain_detach_iommu(info->domain, iommu);

	info->domain = NULL;

}



static int md_domain_init(struct dmar_domain *domain, int guest_width)

{

	int adjust_width;
@@ -4232,7 +4264,7 @@ static int intel_iommu_attach_device(struct iommu_domain *domain, 
		struct device_domain_info *info = dev_iommu_priv_get(dev);



		if (info->domain)

			dmar_remove_one_dev_info(dev);

			device_block_translation(dev);

	}



	ret = prepare_domain_attach_device(domain, dev);