1 /* 2 * arch/arm/include/asm/pgalloc.h 3 * 4 * Copyright (C) 2000-2001 Russell King 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 #ifndef _ASMARM_PGALLOC_H 11 #define _ASMARM_PGALLOC_H 12 13 #include <linux/pagemap.h> 14 15 #include <asm/domain.h> 16 #include <asm/pgtable-hwdef.h> 17 #include <asm/processor.h> 18 #include <asm/cacheflush.h> 19 #include <asm/tlbflush.h> 20 21 #define check_pgt_cache() do { } while (0) 22 23 #ifdef CONFIG_MMU 24 25 #define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER)) 26 #define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL)) 27 28 #ifdef CONFIG_ARM_LPAE 29 30 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr) 31 { 32 return (pmd_t *)get_zeroed_page(GFP_KERNEL | __GFP_REPEAT); 33 } 34 35 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd) 36 { 37 BUG_ON((unsigned long)pmd & (PAGE_SIZE-1)); 38 free_page((unsigned long)pmd); 39 } 40 41 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) 42 { 43 set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE)); 44 } 45 46 #else /* !CONFIG_ARM_LPAE */ 47 48 /* 49 * Since we have only two-level page tables, these are trivial 50 */ 51 #define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); }) 52 #define pmd_free(mm, pmd) do { } while (0) 53 #define pud_populate(mm,pmd,pte) BUG() 54 55 #endif /* CONFIG_ARM_LPAE */ 56 57 extern pgd_t *pgd_alloc(struct mm_struct *mm); 58 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd); 59 60 #define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO) 61 62 static inline void clean_pte_table(pte_t *pte) 63 { 64 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE); 65 } 66 67 /* 68 * Allocate one PTE table. 69 * 70 * This actually allocates two hardware PTE tables, but we wrap this up 71 * into one table thus: 72 * 73 * +------------+ 74 * | Linux pt 0 | 75 * +------------+ 76 * | Linux pt 1 | 77 * +------------+ 78 * | h/w pt 0 | 79 * +------------+ 80 * | h/w pt 1 | 81 * +------------+ 82 */ 83 static inline pte_t * 84 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr) 85 { 86 pte_t *pte; 87 88 pte = (pte_t *)__get_free_page(PGALLOC_GFP); 89 if (pte) 90 clean_pte_table(pte); 91 92 return pte; 93 } 94 95 static inline pgtable_t 96 pte_alloc_one(struct mm_struct *mm, unsigned long addr) 97 { 98 struct page *pte; 99 100 #ifdef CONFIG_HIGHPTE 101 pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0); 102 #else 103 pte = alloc_pages(PGALLOC_GFP, 0); 104 #endif 105 if (!pte) 106 return NULL; 107 if (!PageHighMem(pte)) 108 clean_pte_table(page_address(pte)); 109 if (!pgtable_page_ctor(pte)) { 110 __free_page(pte); 111 return NULL; 112 } 113 return pte; 114 } 115 116 /* 117 * Free one PTE table. 118 */ 119 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) 120 { 121 if (pte) 122 free_page((unsigned long)pte); 123 } 124 125 static inline void pte_free(struct mm_struct *mm, pgtable_t pte) 126 { 127 pgtable_page_dtor(pte); 128 __free_page(pte); 129 } 130 131 static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte, 132 pmdval_t prot) 133 { 134 pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot; 135 pmdp[0] = __pmd(pmdval); 136 #ifndef CONFIG_ARM_LPAE 137 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); 138 #endif 139 flush_pmd_entry(pmdp); 140 } 141 142 /* 143 * Populate the pmdp entry with a pointer to the pte. This pmd is part 144 * of the mm address space. 145 * 146 * Ensure that we always set both PMD entries. 147 */ 148 static inline void 149 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep) 150 { 151 /* 152 * The pmd must be loaded with the physical address of the PTE table 153 */ 154 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE); 155 } 156 157 static inline void 158 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) 159 { 160 extern pmdval_t user_pmd_table; 161 pmdval_t prot; 162 163 if (__LINUX_ARM_ARCH__ >= 6 && !IS_ENABLED(CONFIG_ARM_LPAE)) 164 prot = user_pmd_table; 165 else 166 prot = _PAGE_USER_TABLE; 167 168 __pmd_populate(pmdp, page_to_phys(ptep), prot); 169 } 170 #define pmd_pgtable(pmd) pmd_page(pmd) 171 172 #endif /* CONFIG_MMU */ 173 174 #endif 175