arm: dma-mapping: Reset the device's dma_ops (d3e01c51) · Commits · 戴 / test

arch_teardown_dma_ops() being the inverse of arch_setup_dma_ops() ,dma_ops should be cleared in the teardown path. Currently, only the device's iommu mapping structures are cleared in arch_teardown_dma_ops, but not the dma_ops. So on the next reprobe, dma_ops left in place is stale from the first IOMMU setup, but iommu mappings has been disposed of. This is a problem when the probe of the device is deferred and recalled with the IOMMU probe deferral. So for fixing this, slightly refactor by moving the code from __arm_iommu_detach_device to arm_iommu_detach_device and cleanup the former. This takes care of resetting the dma_ops in the teardown path. Fixes: ("of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices") Reviewed-by:

Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by:

Sricharan R <sricharan@codeaurora.org> Signed-off-by:

Joerg Roedel <jroedel@suse.de>

arch/arm/mm/dma-mapping.c

+10 −15

Original line number	Diff line number	Diff line
		@@ -2311,7 +2311,14 @@ int arm_iommu_attach_device(struct device *dev,
		}
		EXPORT_SYMBOL_GPL(arm_iommu_attach_device);

		static void __arm_iommu_detach_device(struct device *dev)
		/**
		* arm_iommu_detach_device
		* @dev: valid struct device pointer
		*
		* Detaches the provided device from a previously attached map.
		* This voids the dma operations (dma_map_ops pointer)
		*/
		void arm_iommu_detach_device(struct device *dev)
		{
		struct dma_iommu_mapping *mapping;

		@@ -2324,22 +2331,10 @@ static void __arm_iommu_detach_device(struct device *dev)
		iommu_detach_device(mapping->domain, dev);
		kref_put(&mapping->kref, release_iommu_mapping);
		to_dma_iommu_mapping(dev) = NULL;
		set_dma_ops(dev, NULL);

		pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev));
		}

		/**
		* arm_iommu_detach_device
		* @dev: valid struct device pointer
		*
		* Detaches the provided device from a previously attached map.
		* This voids the dma operations (dma_map_ops pointer)
		*/
		void arm_iommu_detach_device(struct device *dev)
		{
		__arm_iommu_detach_device(dev);
		set_dma_ops(dev, NULL);
		}
		EXPORT_SYMBOL_GPL(arm_iommu_detach_device);

		static const struct dma_map_ops *arm_get_iommu_dma_map_ops(bool coherent)
		@@ -2379,7 +2374,7 @@ static void arm_teardown_iommu_dma_ops(struct device *dev)
		if (!mapping)
		return;

		__arm_iommu_detach_device(dev);
		arm_iommu_detach_device(dev);
		arm_iommu_release_mapping(mapping);
		}

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