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 /* 29 * Since we have only two-level page tables, these are trivial 30 */ 31 #define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); }) 32 #define pmd_free(mm, pmd) do { } while (0) 33 #define pgd_populate(mm,pmd,pte) BUG() 34 35 extern pgd_t *pgd_alloc(struct mm_struct *mm); 36 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd); 37 38 #define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO) 39 40 static inline void clean_pte_table(pte_t *pte) 41 { 42 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE); 43 } 44 45 /* 46 * Allocate one PTE table. 47 * 48 * This actually allocates two hardware PTE tables, but we wrap this up 49 * into one table thus: 50 * 51 * +------------+ 52 * | Linux pt 0 | 53 * +------------+ 54 * | Linux pt 1 | 55 * +------------+ 56 * | h/w pt 0 | 57 * +------------+ 58 * | h/w pt 1 | 59 * +------------+ 60 */ 61 static inline pte_t * 62 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr) 63 { 64 pte_t *pte; 65 66 pte = (pte_t *)__get_free_page(PGALLOC_GFP); 67 if (pte) 68 clean_pte_table(pte); 69 70 return pte; 71 } 72 73 static inline pgtable_t 74 pte_alloc_one(struct mm_struct *mm, unsigned long addr) 75 { 76 struct page *pte; 77 78 #ifdef CONFIG_HIGHPTE 79 pte = alloc_pages(PGALLOC_GFP | __GFP_HIGHMEM, 0); 80 #else 81 pte = alloc_pages(PGALLOC_GFP, 0); 82 #endif 83 if (pte) { 84 if (!PageHighMem(pte)) 85 clean_pte_table(page_address(pte)); 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 free_page((unsigned long)pte); 99 } 100 101 static inline void pte_free(struct mm_struct *mm, pgtable_t pte) 102 { 103 pgtable_page_dtor(pte); 104 __free_page(pte); 105 } 106 107 static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte, 108 unsigned long prot) 109 { 110 unsigned long pmdval = (pte + PTE_HWTABLE_OFF) | prot; 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 /* 126 * The pmd must be loaded with the physical address of the PTE table 127 */ 128 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE); 129 } 130 131 static inline void 132 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) 133 { 134 __pmd_populate(pmdp, page_to_phys(ptep), _PAGE_USER_TABLE); 135 } 136 #define pmd_pgtable(pmd) pmd_page(pmd) 137 138 #endif /* CONFIG_MMU */ 139 140 #endif 141