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/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 */