arch/s390/include/asm/pgalloc.h

   1 /*
   2  *  S390 version
   3  *    Copyright IBM Corp. 1999, 2000
   4  *    Author(s): Hartmut Penner (hp@de.ibm.com)
   5  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   6  *
   7  *  Derived from "include/asm-i386/pgalloc.h"
   8  *    Copyright (C) 1994  Linus Torvalds
   9  */
  10
  11 #ifndef _S390_PGALLOC_H
  12 #define _S390_PGALLOC_H
  13
  14 #include <linux/threads.h>
  15 #include <linux/gfp.h>
  16 #include <linux/mm.h>
  17
  18 unsigned long *crst_table_alloc(struct mm_struct *);
  19 void crst_table_free(struct mm_struct *, unsigned long *);
  20
  21 unsigned long *page_table_alloc(struct mm_struct *);
  22 void page_table_free(struct mm_struct *, unsigned long *);
  23 void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
  24 extern int page_table_allocate_pgste;
  25
  26 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
  27 {
  28         typedef struct { char _[n]; } addrtype;
  29
  30         *s = val;
  31         n = (n / 256) - 1;
  32         asm volatile(
  33                 "       mvc     8(248,%0),0(%0)\n"
  34                 "0:     mvc     256(256,%0),0(%0)\n"
  35                 "       la      %0,256(%0)\n"
  36                 "       brct    %1,0b\n"
  37                 : "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
  38                 : "m" (*(addrtype *) s));
  39 }
  40
  41 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  42 {
  43         clear_table(crst, entry, sizeof(unsigned long)*2048);
  44 }
  45
  46 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  47 {
  48         if (mm->context.asce_limit <= (1UL << 31))
  49                 return _SEGMENT_ENTRY_EMPTY;
  50         if (mm->context.asce_limit <= (1UL << 42))
  51                 return _REGION3_ENTRY_EMPTY;
  52         return _REGION2_ENTRY_EMPTY;
  53 }
  54
  55 int crst_table_upgrade(struct mm_struct *, unsigned long limit);
  56 void crst_table_downgrade(struct mm_struct *, unsigned long limit);
  57
  58 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
  59 {
  60         unsigned long *table = crst_table_alloc(mm);
  61         if (table)
  62                 crst_table_init(table, _REGION3_ENTRY_EMPTY);
  63         return (pud_t *) table;
  64 }
  65 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
  66
  67 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  68 {
  69         unsigned long *table = crst_table_alloc(mm);
  70
  71         if (!table)
  72                 return NULL;
  73         crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
  74         if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
  75                 crst_table_free(mm, table);
  76                 return NULL;
  77         }
  78         return (pmd_t *) table;
  79 }
  80
  81 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
  82 {
  83         pgtable_pmd_page_dtor(virt_to_page(pmd));
  84         crst_table_free(mm, (unsigned long *) pmd);
  85 }
  86
  87 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
  88 {
  89         pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
  90 }
  91
  92 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
  93 {
  94         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
  95 }
  96
  97 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  98 {
  99         unsigned long *table = crst_table_alloc(mm);
 100
 101         if (!table)
 102                 return NULL;
 103         if (mm->context.asce_limit == (1UL << 31)) {
 104                 /* Forking a compat process with 2 page table levels */
 105                 if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
 106                         crst_table_free(mm, table);
 107                         return NULL;
 108                 }
 109         }
 110         return (pgd_t *) table;
 111 }
 112
 113 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 114 {
 115         if (mm->context.asce_limit == (1UL << 31))
 116                 pgtable_pmd_page_dtor(virt_to_page(pgd));
 117         crst_table_free(mm, (unsigned long *) pgd);
 118 }
 119
 120 static inline void pmd_populate(struct mm_struct *mm,
 121                                 pmd_t *pmd, pgtable_t pte)
 122 {
 123         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 124 }
 125
 126 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
 127
 128 #define pmd_pgtable(pmd) \
 129         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 130
 131 /*
 132  * page table entry allocation/free routines.
 133  */
 134 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 135 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 136
 137 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 138 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 139
 140 extern void rcu_table_freelist_finish(void);
 141
 142 #endif /* _S390_PGALLOC_H */