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 #define p4d_free(mm, p4d) crst_table_free(mm, (unsigned long *) p4d)
  60
  61 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
  62 {
  63         unsigned long *table = crst_table_alloc(mm);
  64         if (table)
  65                 crst_table_init(table, _REGION3_ENTRY_EMPTY);
  66         return (pud_t *) table;
  67 }
  68 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
  69
  70 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  71 {
  72         unsigned long *table = crst_table_alloc(mm);
  73
  74         if (!table)
  75                 return NULL;
  76         crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
  77         if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
  78                 crst_table_free(mm, table);
  79                 return NULL;
  80         }
  81         return (pmd_t *) table;
  82 }
  83
  84 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
  85 {
  86         pgtable_pmd_page_dtor(virt_to_page(pmd));
  87         crst_table_free(mm, (unsigned long *) pmd);
  88 }
  89
  90 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
  91 {
  92         pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d);
  93 }
  94
  95 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
  96 {
  97         p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud);
  98 }
  99
 100 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 101 {
 102         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
 103 }
 104
 105 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 106 {
 107         unsigned long *table = crst_table_alloc(mm);
 108
 109         if (!table)
 110                 return NULL;
 111         if (mm->context.asce_limit == _REGION3_SIZE) {
 112                 /* Forking a compat process with 2 page table levels */
 113                 if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
 114                         crst_table_free(mm, table);
 115                         return NULL;
 116                 }
 117         }
 118         return (pgd_t *) table;
 119 }
 120
 121 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 122 {
 123         if (mm->context.asce_limit == _REGION3_SIZE)
 124                 pgtable_pmd_page_dtor(virt_to_page(pgd));
 125         crst_table_free(mm, (unsigned long *) pgd);
 126 }
 127
 128 static inline void pmd_populate(struct mm_struct *mm,
 129                                 pmd_t *pmd, pgtable_t pte)
 130 {
 131         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 132 }
 133
 134 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
 135
 136 #define pmd_pgtable(pmd) \
 137         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 138
 139 /*
 140  * page table entry allocation/free routines.
 141  */
 142 #define pte_alloc_one_kernel(mm) ((pte_t *)page_table_alloc(mm))
 143 #define pte_alloc_one(mm) ((pte_t *)page_table_alloc(mm))
 144
 145 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 146 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 147
 148 extern void rcu_table_freelist_finish(void);
 149
 150 void vmem_map_init(void);
 151 void *vmem_crst_alloc(unsigned long val);
 152 pte_t *vmem_pte_alloc(void);
 153
 154 unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages);
 155 void base_asce_free(unsigned long asce);
 156
 157 #endif /* _S390_PGALLOC_H */