1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_DMA_MAPPING_H 3 #define _LINUX_DMA_MAPPING_H 4 5 #ifdef CONFIG_HAS_DMA 6 # error Virtio userspace code does not support CONFIG_HAS_DMA 7 #endif 8 9 #define PCI_DMA_BUS_IS_PHYS 1 10 11 enum dma_data_direction { 12 DMA_BIDIRECTIONAL = 0, 13 DMA_TO_DEVICE = 1, 14 DMA_FROM_DEVICE = 2, 15 DMA_NONE = 3, 16 }; 17 18 #define dma_alloc_coherent(d, s, hp, f) ({ \ 19 void *__dma_alloc_coherent_p = kmalloc((s), (f)); \ 20 *(hp) = (unsigned long)__dma_alloc_coherent_p; \ 21 __dma_alloc_coherent_p; \ 22 }) 23 24 #define dma_free_coherent(d, s, p, h) kfree(p) 25 26 #define dma_map_page(d, p, o, s, dir) (page_to_phys(p) + (o)) 27 28 #define dma_map_single(d, p, s, dir) (virt_to_phys(p)) 29 #define dma_mapping_error(...) (0) 30 31 #define dma_unmap_single(...) do { } while (0) 32 #define dma_unmap_page(...) do { } while (0) 33 34 #endif 35