Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
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linux
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