ARM's arch_setup_dma_ops / arm_setup_iommu_dma_ops creates a custom IOMMU domain for DMA API usage, and continues to do so when the IOMMU driver doesn't explicitly request a DMA default domain type.
When, however, that DMA default domain is requested and the core owns the domain, we need to skip our own domain management. Add checks to arm_setup/teardown_iommu_dma_ops for these cases. Signed-off-by: Mikko Perttunen <[email protected]> --- arch/arm/mm/dma-mapping.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index e0d58778c5f5..91f12fb91509 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1761,9 +1761,18 @@ EXPORT_SYMBOL_GPL(arm_iommu_detach_device); static void arm_setup_iommu_dma_ops(struct device *dev) { - struct dma_iommu_mapping *mapping; + struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev); u64 dma_base = 0, size = 1ULL << 32; + /* + * An existing cookie means the core owns the domain. Only set the + * per-binding DMA ops. + */ + if (mapping) { + set_dma_ops(dev, &iommu_ops); + return; + } + if (dev->dma_range_map) { dma_base = dma_range_map_min(dev->dma_range_map); size = dma_range_map_max(dev->dma_range_map) - dma_base; @@ -1792,6 +1801,9 @@ static void arm_teardown_iommu_dma_ops(struct device *dev) if (!mapping) return; + if (!mapping->owns_domain) + return; + arm_iommu_detach_device(dev); arm_iommu_release_mapping(mapping); } -- 2.55.0
