dma-mapping.h

 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
 9enum dma_data_direction {
10	DMA_BIDIRECTIONAL = 0,
11	DMA_TO_DEVICE = 1,
12	DMA_FROM_DEVICE = 2,
13	DMA_NONE = 3,
14};
15
16#define dma_alloc_coherent(d, s, hp, f) ({ \
17	void *__dma_alloc_coherent_p = kmalloc((s), (f)); \
18	*(hp) = (unsigned long)__dma_alloc_coherent_p; \
19	__dma_alloc_coherent_p; \
20})
21
22#define dma_free_coherent(d, s, p, h) kfree(p)
23
24#define dma_map_page(d, p, o, s, dir) (page_to_phys(p) + (o))
25#define dma_map_page_attrs(d, p, o, s, dir, a) (page_to_phys(p) + (o))
26
27#define dma_map_single(d, p, s, dir) (virt_to_phys(p))
28#define dma_map_single_attrs(d, p, s, dir, a) (virt_to_phys(p))
29#define dma_mapping_error(...) (0)
30
31#define dma_unmap_single(d, a, s, r) do { (void)(d); (void)(a); (void)(s); (void)(r); } while (0)
32#define dma_unmap_page(d, a, s, r) do { (void)(d); (void)(a); (void)(s); (void)(r); } while (0)
33#define dma_unmap_page_attrs(d, a, s, r, t) do { \
34	(void)(d); (void)(a); (void)(s); (void)(r); (void)(t); \
35} while (0)
36
37#define sg_dma_address(sg) (0)
38#define sg_dma_len(sg) (0)
39#define dma_need_sync(v, a) (0)
40#define dma_unmap_single_attrs(d, a, s, r, t) do { \
41	(void)(d); (void)(a); (void)(s); (void)(r); (void)(t); \
42} while (0)
43#define dma_sync_single_range_for_cpu(d, a, o, s, r) do { \
44	(void)(d); (void)(a); (void)(o); (void)(s); (void)(r); \
45} while (0)
46#define dma_sync_single_range_for_device(d, a, o, s, r) do { \
47	(void)(d); (void)(a); (void)(o); (void)(s); (void)(r); \
48} while (0)
49#define dma_max_mapping_size(...) SIZE_MAX
50
51/*
52 * A dma_addr_t can hold any valid DMA or bus address for the platform.  It can
53 * be given to a device to use as a DMA source or target.  It is specific to a
54 * given device and there may be a translation between the CPU physical address
55 * space and the bus address space.
56 *
57 * DMA_MAPPING_ERROR is the magic error code if a mapping failed.  It should not
58 * be used directly in drivers, but checked for using dma_mapping_error()
59 * instead.
60 */
61#define DMA_MAPPING_ERROR		(~(dma_addr_t)0)
62
63#endif