Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_MEMORY_MODEL_H
3#define __ASM_MEMORY_MODEL_H
4
5#include <linux/pfn.h>
6
7#ifndef __ASSEMBLY__
8
9/*
10 * supports 3 memory models.
11 */
12#if defined(CONFIG_FLATMEM)
13
14#ifndef ARCH_PFN_OFFSET
15#define ARCH_PFN_OFFSET (0UL)
16#endif
17
18#define __pfn_to_page(pfn) (mem_map + ((pfn) - ARCH_PFN_OFFSET))
19#define __page_to_pfn(page) ((unsigned long)((page) - mem_map) + \
20 ARCH_PFN_OFFSET)
21
22/* avoid <linux/mm.h> include hell */
23extern unsigned long max_mapnr;
24
25#ifndef pfn_valid
26static inline int pfn_valid(unsigned long pfn)
27{
28 unsigned long pfn_offset = ARCH_PFN_OFFSET;
29
30 return pfn >= pfn_offset && (pfn - pfn_offset) < max_mapnr;
31}
32#define pfn_valid pfn_valid
33
34#ifndef for_each_valid_pfn
35#define for_each_valid_pfn(pfn, start_pfn, end_pfn) \
36 for ((pfn) = max_t(unsigned long, (start_pfn), ARCH_PFN_OFFSET); \
37 (pfn) < min_t(unsigned long, (end_pfn), \
38 ARCH_PFN_OFFSET + max_mapnr); \
39 (pfn)++)
40#endif /* for_each_valid_pfn */
41#endif /* valid_pfn */
42
43#elif defined(CONFIG_SPARSEMEM_VMEMMAP)
44
45/* memmap is virtually contiguous. */
46#define __pfn_to_page(pfn) (vmemmap + (pfn))
47#define __page_to_pfn(page) (unsigned long)((page) - vmemmap)
48
49#elif defined(CONFIG_SPARSEMEM)
50/*
51 * Note: section's mem_map is encoded to reflect its start_pfn.
52 * section[i].section_mem_map == mem_map's address - start_pfn;
53 */
54#define __page_to_pfn(pg) \
55({ const struct page *__pg = (pg); \
56 int __sec = memdesc_section(__pg->flags); \
57 (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \
58})
59
60#define __pfn_to_page(pfn) \
61({ unsigned long __pfn = (pfn); \
62 struct mem_section *__sec = __pfn_to_section(__pfn); \
63 __section_mem_map_addr(__sec) + __pfn; \
64})
65#endif /* CONFIG_FLATMEM/SPARSEMEM */
66
67/*
68 * Convert a physical address to a Page Frame Number and back
69 */
70#define __phys_to_pfn(paddr) PHYS_PFN(paddr)
71#define __pfn_to_phys(pfn) PFN_PHYS(pfn)
72
73#define page_to_pfn __page_to_pfn
74#define pfn_to_page __pfn_to_page
75
76#ifdef CONFIG_DEBUG_VIRTUAL
77#define page_to_phys(page) \
78({ \
79 unsigned long __pfn = page_to_pfn(page); \
80 \
81 WARN_ON_ONCE(!pfn_valid(__pfn)); \
82 PFN_PHYS(__pfn); \
83})
84#else
85#define page_to_phys(page) PFN_PHYS(page_to_pfn(page))
86#endif /* CONFIG_DEBUG_VIRTUAL */
87#define phys_to_page(phys) pfn_to_page(PHYS_PFN(phys))
88
89#endif /* __ASSEMBLY__ */
90
91#endif