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 <asm/domain.h> 14 #include <asm/pgtable-hwdef.h> 15 #include <asm/processor.h> 16 #include <asm/cacheflush.h> 17 #include <asm/tlbflush.h> 18 19 #define check_pgt_cache() do { } while (0) 20 21 #ifdef CONFIG_MMU 22 23 #define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER)) 24 #define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL)) 25 26 /* 27 * Since we have only two-level page tables, these are trivial 28 */ 29 #define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); }) 30 #define pmd_free(mm, pmd) do { } while (0) 31 #define pgd_populate(mm,pmd,pte) BUG() 32 33 extern pgd_t *get_pgd_slow(struct mm_struct *mm); 34 extern void free_pgd_slow(struct mm_struct *mm, pgd_t *pgd); 35 36 #define pgd_alloc(mm) get_pgd_slow(mm) 37 #define pgd_free(mm, pgd) free_pgd_slow(mm, pgd) 38 39 #define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO) 40 41 /* 42 * Allocate one PTE table. 43 * 44 * This actually allocates two hardware PTE tables, but we wrap this up 45 * into one table thus: 46 * 47 * +------------+ 48 * | h/w pt 0 | 49 * +------------+ 50 * | h/w pt 1 | 51 * +------------+ 52 * | Linux pt 0 | 53 * +------------+ 54 * | Linux pt 1 | 55 * +------------+ 56 */ 57 static inline pte_t * 58 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr) 59 { 60 pte_t *pte; 61 62 pte = (pte_t *)__get_free_page(PGALLOC_GFP); 63 if (pte) { 64 clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE); 65 pte += PTRS_PER_PTE; 66 } 67 68 return pte; 69 } 70 71 static inline pgtable_t 72 pte_alloc_one(struct mm_struct *mm, unsigned long addr) 73 { 74 struct page *pte; 75 76 #ifdef CONFIG_HIGHPTE 77 pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0); 78 #else 79 pte = alloc_pages(PGALLOC_GFP, 0); 80 #endif 81 if (pte) { 82 if (!PageHighMem(pte)) { 83 void *page = page_address(pte); 84 clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE); 85 } 86 pgtable_page_ctor(pte); 87 } 88 89 return pte; 90 } 91 92 /* 93 * Free one PTE table. 94 */ 95 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) 96 { 97 if (pte) { 98 pte -= PTRS_PER_PTE; 99 free_page((unsigned long)pte); 100 } 101 } 102 103 static inline void pte_free(struct mm_struct *mm, pgtable_t pte) 104 { 105 pgtable_page_dtor(pte); 106 __free_page(pte); 107 } 108 109 static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval) 110 { 111 pmdp[0] = __pmd(pmdval); 112 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); 113 flush_pmd_entry(pmdp); 114 } 115 116 /* 117 * Populate the pmdp entry with a pointer to the pte. This pmd is part 118 * of the mm address space. 119 * 120 * Ensure that we always set both PMD entries. 121 */ 122 static inline void 123 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep) 124 { 125 unsigned long pte_ptr = (unsigned long)ptep; 126 127 /* 128 * The pmd must be loaded with the physical 129 * address of the PTE table 130 */ 131 pte_ptr -= PTRS_PER_PTE * sizeof(void *); 132 __pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE); 133 } 134 135 static inline void 136 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) 137 { 138 __pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE); 139 } 140 #define pmd_pgtable(pmd) pmd_page(pmd) 141 142 #endif /* CONFIG_MMU */ 143 144 #endif 145