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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * arch/arm/include/asm/pgalloc.h
4 *
5 * Copyright (C) 2000-2001 Russell King
6 */
7#ifndef _ASMARM_PGALLOC_H
8#define _ASMARM_PGALLOC_H
9
10#include <linux/pagemap.h>
11
12#include <asm/domain.h>
13#include <asm/pgtable-hwdef.h>
14#include <asm/processor.h>
15#include <asm/cacheflush.h>
16#include <asm/tlbflush.h>
17
18#ifdef CONFIG_MMU
19
20#define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
21#define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))
22
23#ifdef CONFIG_ARM_LPAE
24
25static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
26{
27 set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE));
28}
29
30#else /* !CONFIG_ARM_LPAE */
31
32/*
33 * Since we have only two-level page tables, these are trivial
34 */
35#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
36#define pmd_free(mm, pmd) do { } while (0)
37#define pud_populate(mm,pmd,pte) BUG()
38
39#endif /* CONFIG_ARM_LPAE */
40
41extern pgd_t *pgd_alloc(struct mm_struct *mm);
42extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
43
44static inline void clean_pte_table(pte_t *pte)
45{
46 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
47}
48
49/*
50 * Allocate one PTE table.
51 *
52 * This actually allocates two hardware PTE tables, but we wrap this up
53 * into one table thus:
54 *
55 * +------------+
56 * | Linux pt 0 |
57 * +------------+
58 * | Linux pt 1 |
59 * +------------+
60 * | h/w pt 0 |
61 * +------------+
62 * | h/w pt 1 |
63 * +------------+
64 */
65
66#define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
67#define __HAVE_ARCH_PTE_ALLOC_ONE
68#define __HAVE_ARCH_PGD_FREE
69#include <asm-generic/pgalloc.h>
70
71static inline pte_t *
72pte_alloc_one_kernel(struct mm_struct *mm)
73{
74 pte_t *pte = __pte_alloc_one_kernel(mm);
75
76 if (pte)
77 clean_pte_table(pte);
78
79 return pte;
80}
81
82#ifdef CONFIG_HIGHPTE
83#define PGTABLE_HIGHMEM __GFP_HIGHMEM
84#else
85#define PGTABLE_HIGHMEM 0
86#endif
87
88static inline pgtable_t
89pte_alloc_one(struct mm_struct *mm)
90{
91 struct page *pte;
92
93 pte = __pte_alloc_one(mm, GFP_PGTABLE_USER | PGTABLE_HIGHMEM);
94 if (!pte)
95 return NULL;
96 if (!PageHighMem(pte))
97 clean_pte_table(page_address(pte));
98 return pte;
99}
100
101static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte,
102 pmdval_t prot)
103{
104 pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot;
105 pmdp[0] = __pmd(pmdval);
106#ifndef CONFIG_ARM_LPAE
107 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
108#endif
109 flush_pmd_entry(pmdp);
110}
111
112/*
113 * Populate the pmdp entry with a pointer to the pte. This pmd is part
114 * of the mm address space.
115 *
116 * Ensure that we always set both PMD entries.
117 */
118static inline void
119pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
120{
121 /*
122 * The pmd must be loaded with the physical address of the PTE table
123 */
124 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE);
125}
126
127static inline void
128pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
129{
130 extern pmdval_t user_pmd_table;
131 pmdval_t prot;
132
133 if (__LINUX_ARM_ARCH__ >= 6 && !IS_ENABLED(CONFIG_ARM_LPAE))
134 prot = user_pmd_table;
135 else
136 prot = _PAGE_USER_TABLE;
137
138 __pmd_populate(pmdp, page_to_phys(ptep), prot);
139}
140#define pmd_pgtable(pmd) pmd_page(pmd)
141
142#endif /* CONFIG_MMU */
143
144#endif