xref: /kvm-unit-tests/lib/arm64/asm/pgtable.h (revision 4da0bc9a24a78cf61f046898b24c45577b645492)
1 #ifndef _ASMARM64_PGTABLE_H_
2 #define _ASMARM64_PGTABLE_H_
3 /*
4  * Adapted from arch/arm64/include/asm/pgtable.h
5  *              include/asm-generic/pgtable-nopmd.h
6  *              include/asm-generic/pgtable-nopud.h
7  *              include/linux/mm.h
8  *
9  * Note: some Linux function APIs have been modified. Nothing crazy,
10  *       but if a function took, for example, an mm_struct, then
11  *       that was either removed or replaced.
12  *
13  * Copyright (C) 2017, Red Hat Inc, Andrew Jones <drjones@redhat.com>
14  *
15  * This work is licensed under the terms of the GNU GPL, version 2.
16  */
17 #include <alloc.h>
18 #include <asm/setup.h>
19 #include <asm/page.h>
20 #include <asm/pgtable-hwdef.h>
21 
22 #define pgd_none(pgd)		(!pgd_val(pgd))
23 #define pud_none(pud)		(!pud_val(pud))
24 #define pmd_none(pmd)		(!pmd_val(pmd))
25 #define pte_none(pte)		(!pte_val(pte))
26 
27 #define pgd_index(addr) \
28 	(((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
29 #define pgd_offset(pgtable, addr) ((pgtable) + pgd_index(addr))
30 
31 #define pgd_free(pgd) free(pgd)
32 static inline pgd_t *pgd_alloc(void)
33 {
34 	pgd_t *pgd = memalign(PAGE_SIZE, PTRS_PER_PGD * sizeof(pgd_t));
35 	memset(pgd, 0, PTRS_PER_PGD * sizeof(pgd_t));
36 	return pgd;
37 }
38 
39 #define pud_offset(pgd, addr)	((pud_t *)pgd)
40 #define pud_free(pud)
41 #define pud_alloc(pgd, addr)	pud_offset(pgd, addr)
42 
43 #define pmd_offset(pud, addr)	((pmd_t *)pud)
44 #define pmd_free(pmd)
45 #define pmd_alloc(pud, addr)	pmd_offset(pud, addr)
46 
47 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
48 {
49 	return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
50 }
51 
52 #define pte_index(addr) \
53 	(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
54 #define pte_offset(pmd, addr) \
55 	(pmd_page_vaddr(*(pmd)) + pte_index(addr))
56 
57 #define pte_free(pte) free(pte)
58 static inline pte_t *pte_alloc_one(void)
59 {
60 	pte_t *pte = memalign(PAGE_SIZE, PTRS_PER_PTE * sizeof(pte_t));
61 	memset(pte, 0, PTRS_PER_PTE * sizeof(pte_t));
62 	return pte;
63 }
64 static inline pte_t *pte_alloc(pmd_t *pmd, unsigned long addr)
65 {
66 	if (pmd_none(*pmd)) {
67 		pte_t *pte = pte_alloc_one();
68 		pmd_val(*pmd) = __pa(pte) | PMD_TYPE_TABLE;
69 	}
70 	return pte_offset(pmd, addr);
71 }
72 
73 #endif /* _ASMARM64_PGTABLE_H_ */
74