1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * S390 version 4 * Copyright IBM Corp. 1999, 2000 5 * Author(s): Hartmut Penner (hp@de.ibm.com) 6 * Martin Schwidefsky (schwidefsky@de.ibm.com) 7 * 8 * Derived from "include/asm-i386/pgalloc.h" 9 * Copyright (C) 1994 Linus Torvalds 10 */ 11 12 #ifndef _S390_PGALLOC_H 13 #define _S390_PGALLOC_H 14 15 #include <linux/threads.h> 16 #include <linux/gfp.h> 17 #include <linux/mm.h> 18 19 #define CRST_ALLOC_ORDER 2 20 21 unsigned long *crst_table_alloc(struct mm_struct *); 22 void crst_table_free(struct mm_struct *, unsigned long *); 23 24 unsigned long *page_table_alloc(struct mm_struct *); 25 struct page *page_table_alloc_pgste(struct mm_struct *mm); 26 void page_table_free(struct mm_struct *, unsigned long *); 27 void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long); 28 void page_table_free_pgste(struct page *page); 29 extern int page_table_allocate_pgste; 30 31 static inline void clear_table(unsigned long *s, unsigned long val, size_t n) 32 { 33 struct addrtype { char _[256]; }; 34 int i; 35 36 for (i = 0; i < n; i += 256) { 37 *s = val; 38 asm volatile( 39 "mvc 8(248,%[s]),0(%[s])\n" 40 : "+m" (*(struct addrtype *) s) 41 : [s] "a" (s)); 42 s += 256 / sizeof(long); 43 } 44 } 45 46 static inline void crst_table_init(unsigned long *crst, unsigned long entry) 47 { 48 clear_table(crst, entry, _CRST_TABLE_SIZE); 49 } 50 51 static inline unsigned long pgd_entry_type(struct mm_struct *mm) 52 { 53 if (mm->context.asce_limit <= _REGION3_SIZE) 54 return _SEGMENT_ENTRY_EMPTY; 55 if (mm->context.asce_limit <= _REGION2_SIZE) 56 return _REGION3_ENTRY_EMPTY; 57 if (mm->context.asce_limit <= _REGION1_SIZE) 58 return _REGION2_ENTRY_EMPTY; 59 return _REGION1_ENTRY_EMPTY; 60 } 61 62 int crst_table_upgrade(struct mm_struct *mm, unsigned long limit); 63 void crst_table_downgrade(struct mm_struct *); 64 65 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long address) 66 { 67 unsigned long *table = crst_table_alloc(mm); 68 69 if (table) 70 crst_table_init(table, _REGION2_ENTRY_EMPTY); 71 return (p4d_t *) table; 72 } 73 #define p4d_free(mm, p4d) crst_table_free(mm, (unsigned long *) p4d) 74 75 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address) 76 { 77 unsigned long *table = crst_table_alloc(mm); 78 if (table) 79 crst_table_init(table, _REGION3_ENTRY_EMPTY); 80 return (pud_t *) table; 81 } 82 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud) 83 84 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr) 85 { 86 unsigned long *table = crst_table_alloc(mm); 87 88 if (!table) 89 return NULL; 90 crst_table_init(table, _SEGMENT_ENTRY_EMPTY); 91 if (!pgtable_pmd_page_ctor(virt_to_page(table))) { 92 crst_table_free(mm, table); 93 return NULL; 94 } 95 return (pmd_t *) table; 96 } 97 98 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd) 99 { 100 pgtable_pmd_page_dtor(virt_to_page(pmd)); 101 crst_table_free(mm, (unsigned long *) pmd); 102 } 103 104 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d) 105 { 106 pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d); 107 } 108 109 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud) 110 { 111 p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud); 112 } 113 114 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd) 115 { 116 pud_val(*pud) = _REGION3_ENTRY | __pa(pmd); 117 } 118 119 static inline pgd_t *pgd_alloc(struct mm_struct *mm) 120 { 121 unsigned long *table = crst_table_alloc(mm); 122 123 if (!table) 124 return NULL; 125 if (mm->context.asce_limit == _REGION3_SIZE) { 126 /* Forking a compat process with 2 page table levels */ 127 if (!pgtable_pmd_page_ctor(virt_to_page(table))) { 128 crst_table_free(mm, table); 129 return NULL; 130 } 131 } 132 return (pgd_t *) table; 133 } 134 135 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) 136 { 137 if (mm->context.asce_limit == _REGION3_SIZE) 138 pgtable_pmd_page_dtor(virt_to_page(pgd)); 139 crst_table_free(mm, (unsigned long *) pgd); 140 } 141 142 static inline void pmd_populate(struct mm_struct *mm, 143 pmd_t *pmd, pgtable_t pte) 144 { 145 pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte); 146 } 147 148 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte) 149 150 #define pmd_pgtable(pmd) \ 151 (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE) 152 153 /* 154 * page table entry allocation/free routines. 155 */ 156 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm)) 157 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm)) 158 159 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte) 160 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte) 161 162 extern void rcu_table_freelist_finish(void); 163 164 void vmem_map_init(void); 165 void *vmem_crst_alloc(unsigned long val); 166 pte_t *vmem_pte_alloc(void); 167 168 #endif /* _S390_PGALLOC_H */ 169