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 *, unsigned long);
  22 void page_table_free(struct mm_struct *, unsigned long *);
  23 void page_table_free_rcu(struct mmu_gather *, unsigned long *);
  24
  25 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
  26 {
  27         typedef struct { char _[n]; } addrtype;
  28
  29         *s = val;
  30         n = (n / 256) - 1;
  31         asm volatile(
  32 #ifdef CONFIG_64BIT
  33                 "       mvc     8(248,%0),0(%0)\n"
  34 #else
  35                 "       mvc     4(252,%0),0(%0)\n"
  36 #endif
  37                 "0:     mvc     256(256,%0),0(%0)\n"
  38                 "       la      %0,256(%0)\n"
  39                 "       brct    %1,0b\n"
  40                 : "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
  41                 : "m" (*(addrtype *) s));
  42 }
  43
  44 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  45 {
  46         clear_table(crst, entry, sizeof(unsigned long)*2048);
  47 }
  48
  49 #ifndef CONFIG_64BIT
  50
  51 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  52 {
  53         return _SEGMENT_ENTRY_EMPTY;
  54 }
  55
  56 #define pud_alloc_one(mm,address)               ({ BUG(); ((pud_t *)2); })
  57 #define pud_free(mm, x)                         do { } while (0)
  58
  59 #define pmd_alloc_one(mm,address)               ({ BUG(); ((pmd_t *)2); })
  60 #define pmd_free(mm, x)                         do { } while (0)
  61
  62 #define pgd_populate(mm, pgd, pud)              BUG()
  63 #define pud_populate(mm, pud, pmd)              BUG()
  64
  65 #else /* CONFIG_64BIT */
  66
  67 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  68 {
  69         if (mm->context.asce_limit <= (1UL << 31))
  70                 return _SEGMENT_ENTRY_EMPTY;
  71         if (mm->context.asce_limit <= (1UL << 42))
  72                 return _REGION3_ENTRY_EMPTY;
  73         return _REGION2_ENTRY_EMPTY;
  74 }
  75
  76 int crst_table_upgrade(struct mm_struct *, unsigned long limit);
  77 void crst_table_downgrade(struct mm_struct *, unsigned long limit);
  78
  79 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
  80 {
  81         unsigned long *table = crst_table_alloc(mm);
  82         if (table)
  83                 crst_table_init(table, _REGION3_ENTRY_EMPTY);
  84         return (pud_t *) table;
  85 }
  86 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
  87
  88 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  89 {
  90         unsigned long *table = crst_table_alloc(mm);
  91         if (table)
  92                 crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
  93         return (pmd_t *) table;
  94 }
  95 #define pmd_free(mm, pmd) crst_table_free(mm, (unsigned long *) pmd)
  96
  97 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
  98 {
  99         pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
 100 }
 101
 102 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 103 {
 104         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
 105 }
 106
 107 #endif /* CONFIG_64BIT */
 108
 109 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 110 {
 111         spin_lock_init(&mm->context.list_lock);
 112         INIT_LIST_HEAD(&mm->context.pgtable_list);
 113         INIT_LIST_HEAD(&mm->context.gmap_list);
 114         return (pgd_t *) crst_table_alloc(mm);
 115 }
 116 #define pgd_free(mm, pgd) crst_table_free(mm, (unsigned long *) pgd)
 117
 118 static inline void pmd_populate(struct mm_struct *mm,
 119                                 pmd_t *pmd, pgtable_t pte)
 120 {
 121         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 122 }
 123
 124 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
 125
 126 #define pmd_pgtable(pmd) \
 127         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 128
 129 /*
 130  * page table entry allocation/free routines.
 131  */
 132 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm, vmaddr))
 133 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm, vmaddr))
 134
 135 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 136 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 137
 138 extern void rcu_table_freelist_finish(void);
 139
 140 #endif /* _S390_PGALLOC_H */