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 struct page *page_table_alloc_pgste(struct mm_struct *mm);
  23 void page_table_free(struct mm_struct *, unsigned long *);
  24 void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
  25 void page_table_free_pgste(struct page *page);
  26 extern int page_table_allocate_pgste;
  27
  28 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
  29 {
  30         typedef struct { char _[n]; } addrtype;
  31
  32         *s = val;
  33         n = (n / 256) - 1;
  34         asm volatile(
  35                 "       mvc     8(248,%0),0(%0)\n"
  36                 "0:     mvc     256(256,%0),0(%0)\n"
  37                 "       la      %0,256(%0)\n"
  38                 "       brct    %1,0b\n"
  39                 : "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
  40                 : "m" (*(addrtype *) s));
  41 }
  42
  43 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  44 {
  45         clear_table(crst, entry, sizeof(unsigned long)*2048);
  46 }
  47
  48 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  49 {
  50         if (mm->context.asce_limit <= (1UL << 31))
  51                 return _SEGMENT_ENTRY_EMPTY;
  52         if (mm->context.asce_limit <= (1UL << 42))
  53                 return _REGION3_ENTRY_EMPTY;
  54         return _REGION2_ENTRY_EMPTY;
  55 }
  56
  57 int crst_table_upgrade(struct mm_struct *);
  58 void crst_table_downgrade(struct mm_struct *);
  59
  60 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
  61 {
  62         unsigned long *table = crst_table_alloc(mm);
  63         if (table)
  64                 crst_table_init(table, _REGION3_ENTRY_EMPTY);
  65         return (pud_t *) table;
  66 }
  67 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
  68
  69 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  70 {
  71         unsigned long *table = crst_table_alloc(mm);
  72
  73         if (!table)
  74                 return NULL;
  75         crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
  76         if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
  77                 crst_table_free(mm, table);
  78                 return NULL;
  79         }
  80         return (pmd_t *) table;
  81 }
  82
  83 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
  84 {
  85         pgtable_pmd_page_dtor(virt_to_page(pmd));
  86         crst_table_free(mm, (unsigned long *) pmd);
  87 }
  88
  89 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
  90 {
  91         pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
  92 }
  93
  94 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
  95 {
  96         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
  97 }
  98
  99 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 100 {
 101         unsigned long *table = crst_table_alloc(mm);
 102
 103         if (!table)
 104                 return NULL;
 105         if (mm->context.asce_limit == (1UL << 31)) {
 106                 /* Forking a compat process with 2 page table levels */
 107                 if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
 108                         crst_table_free(mm, table);
 109                         return NULL;
 110                 }
 111         }
 112         return (pgd_t *) table;
 113 }
 114
 115 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 116 {
 117         if (mm->context.asce_limit == (1UL << 31))
 118                 pgtable_pmd_page_dtor(virt_to_page(pgd));
 119         crst_table_free(mm, (unsigned long *) pgd);
 120 }
 121
 122 static inline void pmd_populate(struct mm_struct *mm,
 123                                 pmd_t *pmd, pgtable_t pte)
 124 {
 125         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 126 }
 127
 128 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
 129
 130 #define pmd_pgtable(pmd) \
 131         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 132
 133 /*
 134  * page table entry allocation/free routines.
 135  */
 136 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 137 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 138
 139 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 140 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 141
 142 extern void rcu_table_freelist_finish(void);
 143
 144 #endif /* _S390_PGALLOC_H */