arch/s390/include/asm/pgalloc.h

   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/string.h>
  17 #include <linux/gfp.h>
  18 #include <linux/mm.h>
  19
  20 #define CRST_ALLOC_ORDER 2
  21
  22 unsigned long *crst_table_alloc(struct mm_struct *);
  23 void crst_table_free(struct mm_struct *, unsigned long *);
  24
  25 unsigned long *page_table_alloc(struct mm_struct *);
  26 struct page *page_table_alloc_pgste(struct mm_struct *mm);
  27 void page_table_free(struct mm_struct *, unsigned long *);
  28 void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
  29 void page_table_free_pgste(struct page *page);
  30 extern int page_table_allocate_pgste;
  31
  32 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  33 {
  34         memset64((u64 *)crst, entry, _CRST_ENTRIES);
  35 }
  36
  37 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  38 {
  39         if (mm_pmd_folded(mm))
  40                 return _SEGMENT_ENTRY_EMPTY;
  41         if (mm_pud_folded(mm))
  42                 return _REGION3_ENTRY_EMPTY;
  43         if (mm_p4d_folded(mm))
  44                 return _REGION2_ENTRY_EMPTY;
  45         return _REGION1_ENTRY_EMPTY;
  46 }
  47
  48 int crst_table_upgrade(struct mm_struct *mm, unsigned long limit);
  49 void crst_table_downgrade(struct mm_struct *);
  50
  51 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long address)
  52 {
  53         unsigned long *table = crst_table_alloc(mm);
  54
  55         if (table)
  56                 crst_table_init(table, _REGION2_ENTRY_EMPTY);
  57         return (p4d_t *) table;
  58 }
  59
  60 static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
  61 {
  62         if (!mm_p4d_folded(mm))
  63                 crst_table_free(mm, (unsigned long *) p4d);
  64 }
  65
  66 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
  67 {
  68         unsigned long *table = crst_table_alloc(mm);
  69         if (table)
  70                 crst_table_init(table, _REGION3_ENTRY_EMPTY);
  71         return (pud_t *) table;
  72 }
  73
  74 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
  75 {
  76         if (!mm_pud_folded(mm))
  77                 crst_table_free(mm, (unsigned long *) pud);
  78 }
  79
  80 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  81 {
  82         unsigned long *table = crst_table_alloc(mm);
  83
  84         if (!table)
  85                 return NULL;
  86         crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
  87         if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
  88                 crst_table_free(mm, table);
  89                 return NULL;
  90         }
  91         return (pmd_t *) table;
  92 }
  93
  94 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
  95 {
  96         if (mm_pmd_folded(mm))
  97                 return;
  98         pgtable_pmd_page_dtor(virt_to_page(pmd));
  99         crst_table_free(mm, (unsigned long *) pmd);
 100 }
 101
 102 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 103 {
 104         pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d);
 105 }
 106
 107 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
 108 {
 109         p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud);
 110 }
 111
 112 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 113 {
 114         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
 115 }
 116
 117 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 118 {
 119         unsigned long *table = crst_table_alloc(mm);
 120
 121         if (!table)
 122                 return NULL;
 123         if (mm->context.asce_limit == _REGION3_SIZE) {
 124                 /* Forking a compat process with 2 page table levels */
 125                 if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
 126                         crst_table_free(mm, table);
 127                         return NULL;
 128                 }
 129         }
 130         return (pgd_t *) table;
 131 }
 132
 133 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 134 {
 135         if (mm->context.asce_limit == _REGION3_SIZE)
 136                 pgtable_pmd_page_dtor(virt_to_page(pgd));
 137         crst_table_free(mm, (unsigned long *) pgd);
 138 }
 139
 140 static inline void pmd_populate(struct mm_struct *mm,
 141                                 pmd_t *pmd, pgtable_t pte)
 142 {
 143         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 144 }
 145
 146 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
 147
 148 #define pmd_pgtable(pmd) \
 149         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 150
 151 /*
 152  * page table entry allocation/free routines.
 153  */
 154 #define pte_alloc_one_kernel(mm) ((pte_t *)page_table_alloc(mm))
 155 #define pte_alloc_one(mm) ((pte_t *)page_table_alloc(mm))
 156
 157 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 158 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 159
 160 extern void rcu_table_freelist_finish(void);
 161
 162 void vmem_map_init(void);
 163 void *vmem_crst_alloc(unsigned long val);
 164 pte_t *vmem_pte_alloc(void);
 165
 166 unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages);
 167 void base_asce_free(unsigned long asce);
 168
 169 #endif /* _S390_PGALLOC_H */