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Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_GENERIC_PAGE_H
3#define __ASM_GENERIC_PAGE_H
4/*
5 * Generic page.h implementation, for NOMMU architectures.
6 * This provides the dummy definitions for the memory management.
7 */
8
9#ifdef CONFIG_MMU
10#error need to provide a real asm/page.h
11#endif
12
13
14/* PAGE_SHIFT determines the page size */
15
16#define PAGE_SHIFT 12
17#ifdef __ASSEMBLY__
18#define PAGE_SIZE (1 << PAGE_SHIFT)
19#else
20#define PAGE_SIZE (1UL << PAGE_SHIFT)
21#endif
22#define PAGE_MASK (~(PAGE_SIZE-1))
23
24#include <asm/setup.h>
25
26#ifndef __ASSEMBLY__
27
28#define clear_page(page) memset((page), 0, PAGE_SIZE)
29#define copy_page(to,from) memcpy((to), (from), PAGE_SIZE)
30
31#define clear_user_page(page, vaddr, pg) clear_page(page)
32#define copy_user_page(to, from, vaddr, pg) copy_page(to, from)
33
34/*
35 * These are used to make use of C type-checking..
36 */
37typedef struct {
38 unsigned long pte;
39} pte_t;
40typedef struct {
41 unsigned long pmd[16];
42} pmd_t;
43typedef struct {
44 unsigned long pgd;
45} pgd_t;
46typedef struct {
47 unsigned long pgprot;
48} pgprot_t;
49typedef struct page *pgtable_t;
50
51#define pte_val(x) ((x).pte)
52#define pmd_val(x) ((&x)->pmd[0])
53#define pgd_val(x) ((x).pgd)
54#define pgprot_val(x) ((x).pgprot)
55
56#define __pte(x) ((pte_t) { (x) } )
57#define __pmd(x) ((pmd_t) { (x) } )
58#define __pgd(x) ((pgd_t) { (x) } )
59#define __pgprot(x) ((pgprot_t) { (x) } )
60
61extern unsigned long memory_start;
62extern unsigned long memory_end;
63
64#endif /* !__ASSEMBLY__ */
65
66#define PAGE_OFFSET (0)
67
68#ifndef ARCH_PFN_OFFSET
69#define ARCH_PFN_OFFSET (PAGE_OFFSET >> PAGE_SHIFT)
70#endif
71
72#ifndef __ASSEMBLY__
73
74#define __va(x) ((void *)((unsigned long) (x)))
75#define __pa(x) ((unsigned long) (x))
76
77static inline unsigned long virt_to_pfn(const void *kaddr)
78{
79 return __pa(kaddr) >> PAGE_SHIFT;
80}
81#define virt_to_pfn virt_to_pfn
82static inline void *pfn_to_virt(unsigned long pfn)
83{
84 return __va(pfn) << PAGE_SHIFT;
85}
86#define pfn_to_virt pfn_to_virt
87
88#define virt_to_page(addr) pfn_to_page(virt_to_pfn(addr))
89#define page_to_virt(page) pfn_to_virt(page_to_pfn(page))
90
91#ifndef page_to_phys
92#define page_to_phys(page) ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
93#endif
94
95#define virt_addr_valid(kaddr) (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
96 ((void *)(kaddr) < (void *)memory_end))
97
98#endif /* __ASSEMBLY__ */
99
100#include <asm-generic/memory_model.h>
101#include <asm-generic/getorder.h>
102
103#endif /* __ASM_GENERIC_PAGE_H */