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 if (!PageHighMem(pte)) 107 clean_pte_table(page_address(pte)); 108 pgtable_page_ctor(pte); 109 } 110 111 return pte; 112 } 113 114 /* 115 * Free one PTE table. 116 */ 117 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) 118 { 119 if (pte) 120 free_page((unsigned long)pte); 121 } 122 123 static inline void pte_free(struct mm_struct *mm, pgtable_t pte) 124 { 125 pgtable_page_dtor(pte); 126 __free_page(pte); 127 } 128 129 static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte, 130 pmdval_t prot) 131 { 132 pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot; 133 pmdp[0] = __pmd(pmdval); 134 #ifndef CONFIG_ARM_LPAE 135 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); 136 #endif 137 flush_pmd_entry(pmdp); 138 } 139 140 /* 141 * Populate the pmdp entry with a pointer to the pte. This pmd is part 142 * of the mm address space. 143 * 144 * Ensure that we always set both PMD entries. 145 */ 146 static inline void 147 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep) 148 { 149 /* 150 * The pmd must be loaded with the physical address of the PTE table 151 */ 152 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE); 153 } 154 155 static inline void 156 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) 157 { 158 __pmd_populate(pmdp, page_to_phys(ptep), _PAGE_USER_TABLE); 159 } 160 #define pmd_pgtable(pmd) pmd_page(pmd) 161 162 #endif /* CONFIG_MMU */ 163 164 #endif 165