diff options
| -rw-r--r-- | arch/arm64/include/asm/dma-mapping.h | 4 | ||||
| -rw-r--r-- | arch/arm64/mm/dma-mapping.c | 86 | ||||
| -rw-r--r-- | include/linux/dma-mapping.h | 1 | ||||
| -rw-r--r-- | kernel/dma/Makefile | 2 | ||||
| -rw-r--r-- | kernel/dma/dummy.c | 39 |
5 files changed, 42 insertions, 90 deletions
diff --git a/arch/arm64/include/asm/dma-mapping.h b/arch/arm64/include/asm/dma-mapping.h index c41f3fb1446c..273e778f7de2 100644 --- a/arch/arm64/include/asm/dma-mapping.h +++ b/arch/arm64/include/asm/dma-mapping.h @@ -24,15 +24,13 @@ #include <xen/xen.h> #include <asm/xen/hypervisor.h> -extern const struct dma_map_ops dummy_dma_ops; - static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus) { /* * We expect no ISA devices, and all other DMA masters are expected to * have someone call arch_setup_dma_ops at device creation time. */ - return &dummy_dma_ops; + return &dma_dummy_ops; } void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 4c0f498069e8..6ff6ec8806c1 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -89,92 +89,6 @@ static int __swiotlb_mmap_pfn(struct vm_area_struct *vma, } #endif /* CONFIG_IOMMU_DMA */ -/******************************************** - * The following APIs are for dummy DMA ops * - ********************************************/ - -static void *__dummy_alloc(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t flags, - unsigned long attrs) -{ - return NULL; -} - -static void __dummy_free(struct device *dev, size_t size, - void *vaddr, dma_addr_t dma_handle, - unsigned long attrs) -{ -} - -static int __dummy_mmap(struct device *dev, - struct vm_area_struct *vma, - void *cpu_addr, dma_addr_t dma_addr, size_t size, - unsigned long attrs) -{ - return -ENXIO; -} - -static dma_addr_t __dummy_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, - enum dma_data_direction dir, - unsigned long attrs) -{ - return DMA_MAPPING_ERROR; -} - -static void __dummy_unmap_page(struct device *dev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir, - unsigned long attrs) -{ -} - -static int __dummy_map_sg(struct device *dev, struct scatterlist *sgl, - int nelems, enum dma_data_direction dir, - unsigned long attrs) -{ - return 0; -} - -static void __dummy_unmap_sg(struct device *dev, - struct scatterlist *sgl, int nelems, - enum dma_data_direction dir, - unsigned long attrs) -{ -} - -static void __dummy_sync_single(struct device *dev, - dma_addr_t dev_addr, size_t size, - enum dma_data_direction dir) -{ -} - -static void __dummy_sync_sg(struct device *dev, - struct scatterlist *sgl, int nelems, - enum dma_data_direction dir) -{ -} - -static int __dummy_dma_supported(struct device *hwdev, u64 mask) -{ - return 0; -} - -const struct dma_map_ops dummy_dma_ops = { - .alloc = __dummy_alloc, - .free = __dummy_free, - .mmap = __dummy_mmap, - .map_page = __dummy_map_page, - .unmap_page = __dummy_unmap_page, - .map_sg = __dummy_map_sg, - .unmap_sg = __dummy_unmap_sg, - .sync_single_for_cpu = __dummy_sync_single, - .sync_single_for_device = __dummy_sync_single, - .sync_sg_for_cpu = __dummy_sync_sg, - .sync_sg_for_device = __dummy_sync_sg, - .dma_supported = __dummy_dma_supported, -}; -EXPORT_SYMBOL(dummy_dma_ops); - static int __init arm64_dma_init(void) { WARN_TAINT(ARCH_DMA_MINALIGN < cache_line_size(), diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 0f0078490df4..269ee27fc3d9 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -136,6 +136,7 @@ struct dma_map_ops { extern const struct dma_map_ops dma_direct_ops; extern const struct dma_map_ops dma_virt_ops; +extern const struct dma_map_ops dma_dummy_ops; #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile index a626f643cd63..72ff6e46aa86 100644 --- a/kernel/dma/Makefile +++ b/kernel/dma/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_HAS_DMA) += mapping.o direct.o +obj-$(CONFIG_HAS_DMA) += mapping.o direct.o dummy.o obj-$(CONFIG_DMA_CMA) += contiguous.o obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += coherent.o obj-$(CONFIG_DMA_VIRT_OPS) += virt.o diff --git a/kernel/dma/dummy.c b/kernel/dma/dummy.c new file mode 100644 index 000000000000..05607642c888 --- /dev/null +++ b/kernel/dma/dummy.c @@ -0,0 +1,39 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Dummy DMA ops that always fail. + */ +#include <linux/dma-mapping.h> + +static int dma_dummy_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + return -ENXIO; +} + +static dma_addr_t dma_dummy_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + return DMA_MAPPING_ERROR; +} + +static int dma_dummy_map_sg(struct device *dev, struct scatterlist *sgl, + int nelems, enum dma_data_direction dir, + unsigned long attrs) +{ + return 0; +} + +static int dma_dummy_supported(struct device *hwdev, u64 mask) +{ + return 0; +} + +const struct dma_map_ops dma_dummy_ops = { + .mmap = dma_dummy_mmap, + .map_page = dma_dummy_map_page, + .map_sg = dma_dummy_map_sg, + .dma_supported = dma_dummy_supported, +}; +EXPORT_SYMBOL(dma_dummy_ops); |