ACPI / scan: Refactor _CCA enforcement (e5361ca2) · Commits · 戴 / test

Rather than checking the DMA attribute at each callsite, just pass it through for acpi_dma_configure() to handle directly. That can then deal with the relatively exceptional DEV_DMA_NOT_SUPPORTED case by explicitly installing dummy DMA ops instead of just skipping setup entirely. This will then free up the dev->dma_ops == NULL case for some valuable fastpath optimisations. Signed-off-by:

Robin Murphy <robin.murphy@arm.com> Reviewed-by:

Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by:

Jesper Dangaard Brouer <brouer@redhat.com> Tested-by:

Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by:

Christoph Hellwig <hch@lst.de> Tested-by:

Tony Luck <tony.luck@intel.com>

drivers/acpi/scan.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -1456,6 +1456,11 @@ int acpi_dma_configure(struct device *dev, enum dev_dma_attr attr)
		const struct iommu_ops *iommu;
		u64 dma_addr = 0, size = 0;

		if (attr == DEV_DMA_NOT_SUPPORTED) {
		set_dma_ops(dev, &dma_dummy_ops);
		return 0;
		}

		iort_dma_setup(dev, &dma_addr, &size);

		iommu = iort_iommu_configure(dev);

drivers/base/platform.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -1138,7 +1138,6 @@ int platform_dma_configure(struct device *dev)
		ret = of_dma_configure(dev, dev->of_node, true);
		} else if (has_acpi_companion(dev)) {
		attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
		if (attr != DEV_DMA_NOT_SUPPORTED)
		ret = acpi_dma_configure(dev, attr);
		}

drivers/pci/pci-driver.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -1602,8 +1602,7 @@ static int pci_dma_configure(struct device *dev)
		struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
		enum dev_dma_attr attr = acpi_get_dma_attr(adev);

		if (attr != DEV_DMA_NOT_SUPPORTED)
		ret = acpi_dma_configure(dev, attr);
		ret = acpi_dma_configure(dev, acpi_get_dma_attr(adev));
		}

		pci_put_host_bridge_device(bridge);

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