1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * arch/arm/include/asm/pgalloc.h 4 * 5 * Copyright (C) 2000-2001 Russell King 6 */ 7 #ifndef _ASMARM_PGALLOC_H 8 #define _ASMARM_PGALLOC_H 9 10 #include <linux/pagemap.h> 11 12 #include <asm/domain.h> 13 #include <asm/pgtable-hwdef.h> 14 #include <asm/processor.h> 15 #include <asm/cacheflush.h> 16 #include <asm/tlbflush.h> 17 18 #ifdef CONFIG_MMU 19 20 #define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER)) 21 #define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL)) 22 23 #ifdef CONFIG_ARM_LPAE 24 25 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) 26 { 27 set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE)); 28 } 29 30 #else /* !CONFIG_ARM_LPAE */ 31 32 /* 33 * Since we have only two-level page tables, these are trivial 34 */ 35 #define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); }) 36 #define pmd_free(mm, pmd) do { } while (0) 37 #define pud_populate(mm,pmd,pte) BUG() 38 39 #endif /* CONFIG_ARM_LPAE */ 40 41 extern pgd_t *pgd_alloc(struct mm_struct *mm); 42 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd); 43 44 static inline void clean_pte_table(pte_t *pte) 45 { 46 clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE); 47 } 48 49 /* 50 * Allocate one PTE table. 51 * 52 * This actually allocates two hardware PTE tables, but we wrap this up 53 * into one table thus: 54 * 55 * +------------+ 56 * | Linux pt 0 | 57 * +------------+ 58 * | Linux pt 1 | 59 * +------------+ 60 * | h/w pt 0 | 61 * +------------+ 62 * | h/w pt 1 | 63 * +------------+ 64 */ 65 66 #define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL 67 #define __HAVE_ARCH_PTE_ALLOC_ONE 68 #define __HAVE_ARCH_PGD_FREE 69 #include <asm-generic/pgalloc.h> 70 71 static inline pte_t * 72 pte_alloc_one_kernel(struct mm_struct *mm) 73 { 74 pte_t *pte = __pte_alloc_one_kernel(mm); 75 76 if (pte) 77 clean_pte_table(pte); 78 79 return pte; 80 } 81 82 #ifdef CONFIG_HIGHPTE 83 #define PGTABLE_HIGHMEM __GFP_HIGHMEM 84 #else 85 #define PGTABLE_HIGHMEM 0 86 #endif 87 88 static inline pgtable_t 89 pte_alloc_one(struct mm_struct *mm) 90 { 91 struct page *pte; 92 93 pte = __pte_alloc_one(mm, GFP_PGTABLE_USER | PGTABLE_HIGHMEM); 94 if (!pte) 95 return NULL; 96 if (!PageHighMem(pte)) 97 clean_pte_table(page_address(pte)); 98 return pte; 99 } 100 101 static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte, 102 pmdval_t prot) 103 { 104 pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot; 105 pmdp[0] = __pmd(pmdval); 106 #ifndef CONFIG_ARM_LPAE 107 pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t)); 108 #endif 109 flush_pmd_entry(pmdp); 110 } 111 112 /* 113 * Populate the pmdp entry with a pointer to the pte. This pmd is part 114 * of the mm address space. 115 * 116 * Ensure that we always set both PMD entries. 117 */ 118 static inline void 119 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep) 120 { 121 /* 122 * The pmd must be loaded with the physical address of the PTE table 123 */ 124 __pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE); 125 } 126 127 static inline void 128 pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep) 129 { 130 extern pmdval_t user_pmd_table; 131 pmdval_t prot; 132 133 if (__LINUX_ARM_ARCH__ >= 6 && !IS_ENABLED(CONFIG_ARM_LPAE)) 134 prot = user_pmd_table; 135 else 136 prot = _PAGE_USER_TABLE; 137 138 __pmd_populate(pmdp, page_to_phys(ptep), prot); 139 } 140 #define pmd_pgtable(pmd) pmd_page(pmd) 141 142 #endif /* CONFIG_MMU */ 143 144 #endif 145