| 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 | #define PGD_SIZE (PTRS_PER_PGD * sizeof(pgd_t)) |
| 25 | |
| 26 | static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) |
| 27 | { |
| 28 | set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE)); |
| 29 | } |
| 30 | |
| 31 | #else /* !CONFIG_ARM_LPAE */ |
| 32 | #define PGD_SIZE (PAGE_SIZE << 2) |
| 33 | |
| 34 | /* |
| 35 | * Since we have only two-level page tables, these are trivial |
| 36 | */ |
| 37 | #define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); }) |
| 38 | #define pmd_free(mm, pmd) do { } while (0) |
| 39 | #ifdef CONFIG_KASAN |
| 40 | /* The KASan core unconditionally calls pud_populate() on all architectures */ |
| 41 | #define pud_populate(mm,pmd,pte) do { } while (0) |
| 42 | #else |
| 43 | #define pud_populate(mm,pmd,pte) BUG() |
| 44 | #endif |
| 45 | #endif /* CONFIG_ARM_LPAE */ |
| 46 | |
| 47 | extern pgd_t *pgd_alloc(struct mm_struct *mm); |
| 48 | extern void pgd_free(struct mm_struct *mm, pgd_t *pgd); |
| 49 | |
| 50 | static inline void clean_pte_table(pte_t *pte) |
| 51 | { |
| 52 | clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE); |
| 53 | } |
| 54 | |
| 55 | /* |
| 56 | * Allocate one PTE table. |
| 57 | * |
| 58 | * This actually allocates two hardware PTE tables, but we wrap this up |
| 59 | * into one table thus: |
| 60 | * |
| 61 | * +------------+ |
| 62 | * | Linux pt 0 | |
| 63 | * +------------+ |
| 64 | * | Linux pt 1 | |
| 65 | * +------------+ |
| 66 | * | h/w pt 0 | |
| 67 | * +------------+ |
| 68 | * | h/w pt 1 | |
| 69 | * +------------+ |
| 70 | */ |
| 71 | |
| 72 | #define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL |
| 73 | #define __HAVE_ARCH_PTE_ALLOC_ONE |
| 74 | #define __HAVE_ARCH_PGD_FREE |
| 75 | #include <asm-generic/pgalloc.h> |
| 76 | |
| 77 | static inline pte_t * |
| 78 | pte_alloc_one_kernel(struct mm_struct *mm) |
| 79 | { |
| 80 | pte_t *pte = __pte_alloc_one_kernel(mm); |
| 81 | |
| 82 | if (pte) |
| 83 | clean_pte_table(pte); |
| 84 | |
| 85 | return pte; |
| 86 | } |
| 87 | |
| 88 | #ifdef CONFIG_HIGHPTE |
| 89 | #define PGTABLE_HIGHMEM __GFP_HIGHMEM |
| 90 | #else |
| 91 | #define PGTABLE_HIGHMEM 0 |
| 92 | #endif |
| 93 | |
| 94 | static inline pgtable_t |
| 95 | pte_alloc_one(struct mm_struct *mm) |
| 96 | { |
| 97 | struct page *pte; |
| 98 | |
| 99 | pte = __pte_alloc_one(mm, GFP_PGTABLE_USER | PGTABLE_HIGHMEM); |
| 100 | if (!pte) |
| 101 | return NULL; |
| 102 | if (!PageHighMem(pte)) |
| 103 | clean_pte_table(page_address(pte)); |
| 104 | return pte; |
| 105 | } |
| 106 | |
| 107 | static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte, |
| 108 | pmdval_t prot) |
| 109 | { |
| 110 | pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot; |
| 111 | pmdp[0] = __pmd(pmdval); |
| 112 | #ifndef CONFIG_ARM_LPAE |
| 113 | pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); |
| 114 | #endif |
| 115 | flush_pmd_entry(pmdp); |
| 116 | } |
| 117 | |
| 118 | /* |
| 119 | * Populate the pmdp entry with a pointer to the pte. This pmd is part |
| 120 | * of the mm address space. |
| 121 | * |
| 122 | * Ensure that we always set both PMD entries. |
| 123 | */ |
| 124 | static inline void |
| 125 | pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep) |
| 126 | { |
| 127 | /* |
| 128 | * The pmd must be loaded with the physical address of the PTE table |
| 129 | */ |
| 130 | __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE); |
| 131 | } |
| 132 | |
| 133 | static inline void |
| 134 | pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) |
| 135 | { |
| 136 | extern pmdval_t user_pmd_table; |
| 137 | pmdval_t prot; |
| 138 | |
| 139 | if (__LINUX_ARM_ARCH__ >= 6 && !IS_ENABLED(CONFIG_ARM_LPAE)) |
| 140 | prot = user_pmd_table; |
| 141 | else |
| 142 | prot = _PAGE_USER_TABLE; |
| 143 | |
| 144 | __pmd_populate(pmdp, page_to_phys(ptep), prot); |
| 145 | } |
| 146 | |
| 147 | #endif /* CONFIG_MMU */ |
| 148 | |
| 149 | #endif |