[PATCH v4 1/2] ARM: dma-mapping: Set proper DMA ops in arm_iommu_detach_device()

Thierry Reding
2018-05-30T14:06:24Z

From: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

Instead of setting the DMA ops pointer to NULL, set the correct,
non-IOMMU ops depending on the device's coherency setting.

Signed-off-by: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
Changes in v4:
- new patch to fix existing arm_iommu_detach_device() to do what we need

arch/arm/mm/dma-mapping.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index af27f1c22d93..87a0037574e4 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1151,6 +1151,11 @@ int arm_dma_supported(struct device *dev, u64 mask)
return __dma_supported(dev, mask, false);
}

+static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent)
+{
+ return coherent ? &arm_coherent_dma_ops : &arm_dma_ops;
+}
+
#ifdef CONFIG_ARM_DMA_USE_IOMMU

static int __dma_info_to_prot(enum dma_data_direction dir, unsigned long attrs)
@@ -2296,7 +2301,7 @@ 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);
+ set_dma_ops(dev, arm_get_dma_map_ops(dev->archdata.dma_coherent));

pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev));
}
@@ -2357,11 +2362,6 @@ static void arm_teardown_iommu_dma_ops(struct device *dev) { }

#endif /* CONFIG_ARM_DMA_USE_IOMMU */

-static const struct dma_map_ops *arm_get_dma_map_ops(bool coherent)
-{
- return coherent ? &arm_coherent_dma_ops : &arm_dma_ops;
-}
-
void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
const struct iommu_ops *iommu, bool coherent)
{
--
2.17.0