ARM64: dma-mapping: add support for NO_KERNEL_MAPPING attribute

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index 49b7fec..89d4c74 100644 (file)
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -458,6 +458,9 @@ static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
        if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
                return __atomic_get_pages(cpu_addr);
 
+       if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+               return cpu_addr;
+
        area = find_vm_area(cpu_addr);
        if (!area)
                return NULL;
@@ -534,6 +537,9 @@ static void *__iommu_alloc_attrs(struct device *dev, size_t size,
        if (*handle == DMA_ERROR_CODE)
                goto err_mapping;
 
+       if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+               return pages;
+
        addr = dma_common_pages_remap(pages, size, VM_USERMAP,
                                      __get_dma_pgprot(attrs, prot, coherent),
                                      __builtin_return_address(0));
@@ -563,7 +569,8 @@ static void __iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
                return;
        }
 
-       dma_common_free_remap(cpu_addr, size, VM_USERMAP);
+       if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+               dma_common_free_remap(cpu_addr, size, VM_USERMAP);
 
        iommu_dma_release_iova_mapping(dev, handle, size);
        iommu_dma_free_buffer(dev, pages, size, attrs);