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 *pgd_alloc(struct mm_struct *mm); 34 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd); 35 36 #define PGALLOC_GFP (GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO) 37 38 static inline void clean_pte_table(pte_t *pte) 39 { 40 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE); 41 } 42 43 /* 44 * Allocate one PTE table. 45 * 46 * This actually allocates two hardware PTE tables, but we wrap this up 47 * into one table thus: 48 * 49 * +------------+ 50 * | Linux pt 0 | 51 * +------------+ 52 * | Linux pt 1 | 53 * +------------+ 54 * | h/w pt 0 | 55 * +------------+ 56 * | h/w pt 1 | 57 * +------------+ 58 */ 59 static inline pte_t * 60 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr) 61 { 62 pte_t *pte; 63 64 pte = (pte_t *)__get_free_page(PGALLOC_GFP); 65 if (pte) 66 clean_pte_table(pte); 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 clean_pte_table(page_address(pte)); 84 pgtable_page_ctor(pte); 85 } 86 87 return pte; 88 } 89 90 /* 91 * Free one PTE table. 92 */ 93 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) 94 { 95 if (pte) 96 free_page((unsigned long)pte); 97 } 98 99 static inline void pte_free(struct mm_struct *mm, pgtable_t pte) 100 { 101 pgtable_page_dtor(pte); 102 __free_page(pte); 103 } 104 105 static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte, 106 unsigned long prot) 107 { 108 unsigned long pmdval = (pte + PTE_HWTABLE_OFF) | prot; 109 pmdp[0] = __pmd(pmdval); 110 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); 111 flush_pmd_entry(pmdp); 112 } 113 114 /* 115 * Populate the pmdp entry with a pointer to the pte. This pmd is part 116 * of the mm address space. 117 * 118 * Ensure that we always set both PMD entries. 119 */ 120 static inline void 121 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep) 122 { 123 /* 124 * The pmd must be loaded with the physical address of the PTE table 125 */ 126 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE); 127 } 128 129 static inline void 130 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) 131 { 132 __pmd_populate(pmdp, page_to_phys(ptep), _PAGE_USER_TABLE); 133 } 134 #define pmd_pgtable(pmd) pmd_page(pmd) 135 136 #endif /* CONFIG_MMU */ 137 138 #endif 139