Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_DMA_DIRECT_H
3#define _LINUX_DMA_DIRECT_H 1
4
5#include <linux/dma-mapping.h>
6#include <linux/memblock.h> /* for min_low_pfn */
7#include <linux/mem_encrypt.h>
8
9extern unsigned int zone_dma_bits;
10
11#ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA
12#include <asm/dma-direct.h>
13#else
14static inline dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
15{
16 dma_addr_t dev_addr = (dma_addr_t)paddr;
17
18 return dev_addr - ((dma_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
19}
20
21static inline phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t dev_addr)
22{
23 phys_addr_t paddr = (phys_addr_t)dev_addr;
24
25 return paddr + ((phys_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
26}
27#endif /* !CONFIG_ARCH_HAS_PHYS_TO_DMA */
28
29#ifdef CONFIG_ARCH_HAS_FORCE_DMA_UNENCRYPTED
30bool force_dma_unencrypted(struct device *dev);
31#else
32static inline bool force_dma_unencrypted(struct device *dev)
33{
34 return false;
35}
36#endif /* CONFIG_ARCH_HAS_FORCE_DMA_UNENCRYPTED */
37
38/*
39 * If memory encryption is supported, phys_to_dma will set the memory encryption
40 * bit in the DMA address, and dma_to_phys will clear it. The raw __phys_to_dma
41 * and __dma_to_phys versions should only be used on non-encrypted memory for
42 * special occasions like DMA coherent buffers.
43 */
44static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
45{
46 return __sme_set(__phys_to_dma(dev, paddr));
47}
48
49static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
50{
51 return __sme_clr(__dma_to_phys(dev, daddr));
52}
53
54static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size,
55 bool is_ram)
56{
57 dma_addr_t end = addr + size - 1;
58
59 if (!dev->dma_mask)
60 return false;
61
62 if (is_ram && !IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT) &&
63 min(addr, end) < phys_to_dma(dev, PFN_PHYS(min_low_pfn)))
64 return false;
65
66 return end <= min_not_zero(*dev->dma_mask, dev->bus_dma_limit);
67}
68
69u64 dma_direct_get_required_mask(struct device *dev);
70void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
71 gfp_t gfp, unsigned long attrs);
72void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
73 dma_addr_t dma_addr, unsigned long attrs);
74void *dma_direct_alloc_pages(struct device *dev, size_t size,
75 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs);
76void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
77 dma_addr_t dma_addr, unsigned long attrs);
78struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
79 gfp_t gfp, unsigned long attrs);
80int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt,
81 void *cpu_addr, dma_addr_t dma_addr, size_t size,
82 unsigned long attrs);
83bool dma_direct_can_mmap(struct device *dev);
84int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma,
85 void *cpu_addr, dma_addr_t dma_addr, size_t size,
86 unsigned long attrs);
87int dma_direct_supported(struct device *dev, u64 mask);
88#endif /* _LINUX_DMA_DIRECT_H */