From: Sricharan R Date: Sat, 27 May 2017 13:47:45 +0000 (+0530) Subject: arm: dma-mapping: Reset the device's dma_ops X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d3e01c51598b2639a4830549058500e5f2ace86f;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git arm: dma-mapping: Reset the device's dma_ops 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: 09515ef5ddad ("of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices") Reviewed-by: Laurent Pinchart Signed-off-by: Sricharan R Signed-off-by: Joerg Roedel --- diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index b48998f90bfb..bd83c531828a 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -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); }