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 /* 40 * Allocate one PTE table. 41 * 42 * This actually allocates two hardware PTE tables, but we wrap this up 43 * into one table thus: 44 * 45 * +------------+ 46 * | h/w pt 0 | 47 * +------------+ 48 * | h/w pt 1 | 49 * +------------+ 50 * | Linux pt 0 | 51 * +------------+ 52 * | Linux pt 1 | 53 * +------------+ 54 */ 55 static inline pte_t * 56 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr) 57 { 58 pte_t *pte; 59 60 pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO); 61 if (pte) { 62 clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE); 63 pte += PTRS_PER_PTE; 64 } 65 66 return pte; 67 } 68 69 static inline pgtable_t 70 pte_alloc_one(struct mm_struct *mm, unsigned long addr) 71 { 72 struct page *pte; 73 74 pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0); 75 if (pte) { 76 void *page = page_address(pte); 77 clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE); 78 pgtable_page_ctor(pte); 79 } 80 81 return pte; 82 } 83 84 /* 85 * Free one PTE table. 86 */ 87 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) 88 { 89 if (pte) { 90 pte -= PTRS_PER_PTE; 91 free_page((unsigned long)pte); 92 } 93 } 94 95 static inline void pte_free(struct mm_struct *mm, pgtable_t pte) 96 { 97 pgtable_page_dtor(pte); 98 __free_page(pte); 99 } 100 101 static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval) 102 { 103 pmdp[0] = __pmd(pmdval); 104 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); 105 flush_pmd_entry(pmdp); 106 } 107 108 /* 109 * Populate the pmdp entry with a pointer to the pte. This pmd is part 110 * of the mm address space. 111 * 112 * Ensure that we always set both PMD entries. 113 */ 114 static inline void 115 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep) 116 { 117 unsigned long pte_ptr = (unsigned long)ptep; 118 119 /* 120 * The pmd must be loaded with the physical 121 * address of the PTE table 122 */ 123 pte_ptr -= PTRS_PER_PTE * sizeof(void *); 124 __pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE); 125 } 126 127 static inline void 128 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) 129 { 130 __pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE); 131 } 132 #define pmd_pgtable(pmd) pmd_page(pmd) 133 134 #endif /* CONFIG_MMU */ 135 136 #endif 137