Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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#endif
34
35#elif defined(CONFIG_SPARSEMEM_VMEMMAP)
36
37/* memmap is virtually contiguous. */
38#define __pfn_to_page(pfn) (vmemmap + (pfn))
39#define __page_to_pfn(page) (unsigned long)((page) - vmemmap)
40
41#elif defined(CONFIG_SPARSEMEM)
42/*
43 * Note: section's mem_map is encoded to reflect its start_pfn.
44 * section[i].section_mem_map == mem_map's address - start_pfn;
45 */
46#define __page_to_pfn(pg) \
47({ const struct page *__pg = (pg); \
48 int __sec = page_to_section(__pg); \
49 (unsigned long)(__pg - __section_mem_map_addr(__nr_to_section(__sec))); \
50})
51
52#define __pfn_to_page(pfn) \
53({ unsigned long __pfn = (pfn); \
54 struct mem_section *__sec = __pfn_to_section(__pfn); \
55 __section_mem_map_addr(__sec) + __pfn; \
56})
57#endif /* CONFIG_FLATMEM/SPARSEMEM */
58
59/*
60 * Convert a physical address to a Page Frame Number and back
61 */
62#define __phys_to_pfn(paddr) PHYS_PFN(paddr)
63#define __pfn_to_phys(pfn) PFN_PHYS(pfn)
64
65#define page_to_pfn __page_to_pfn
66#define pfn_to_page __pfn_to_page
67
68#ifdef CONFIG_DEBUG_VIRTUAL
69#define page_to_phys(page) \
70({ \
71 unsigned long __pfn = page_to_pfn(page); \
72 \
73 WARN_ON_ONCE(!pfn_valid(__pfn)); \
74 PFN_PHYS(__pfn); \
75})
76#else
77#define page_to_phys(page) PFN_PHYS(page_to_pfn(page))
78#endif /* CONFIG_DEBUG_VIRTUAL */
79#define phys_to_page(phys) pfn_to_page(PHYS_PFN(phys))
80
81#endif /* __ASSEMBLY__ */
82
83#endif