arch/s390/include/asm/pgalloc.h

   1 /*
   2  *  include/asm-s390/pgalloc.h
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Hartmut Penner (hp@de.ibm.com)
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Derived from "include/asm-i386/pgalloc.h"
  10  *    Copyright (C) 1994  Linus Torvalds
  11  */
  12
  13 #ifndef _S390_PGALLOC_H
  14 #define _S390_PGALLOC_H
  15
  16 #include <linux/threads.h>
  17 #include <linux/gfp.h>
  18 #include <linux/mm.h>
  19
  20 #define check_pgt_cache()       do {} while (0)
  21
  22 unsigned long *crst_table_alloc(struct mm_struct *, int);
  23 void crst_table_free(struct mm_struct *, unsigned long *);
  24 void crst_table_free_rcu(struct mm_struct *, unsigned long *);
  25
  26 unsigned long *page_table_alloc(struct mm_struct *);
  27 void page_table_free(struct mm_struct *, unsigned long *);
  28 void page_table_free_rcu(struct mm_struct *, unsigned long *);
  29 void disable_noexec(struct mm_struct *, struct task_struct *);
  30
  31 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
  32 {
  33         typedef struct { char _[n]; } addrtype;
  34
  35         *s = val;
  36         n = (n / 256) - 1;
  37         asm volatile(
  38 #ifdef CONFIG_64BIT
  39                 "       mvc     8(248,%0),0(%0)\n"
  40 #else
  41                 "       mvc     4(252,%0),0(%0)\n"
  42 #endif
  43                 "0:     mvc     256(256,%0),0(%0)\n"
  44                 "       la      %0,256(%0)\n"
  45                 "       brct    %1,0b\n"
  46                 : "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
  47                 : "m" (*(addrtype *) s));
  48 }
  49
  50 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  51 {
  52         clear_table(crst, entry, sizeof(unsigned long)*2048);
  53         crst = get_shadow_table(crst);
  54         if (crst)
  55                 clear_table(crst, entry, sizeof(unsigned long)*2048);
  56 }
  57
  58 #ifndef __s390x__
  59
  60 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  61 {
  62         return _SEGMENT_ENTRY_EMPTY;
  63 }
  64
  65 #define pud_alloc_one(mm,address)               ({ BUG(); ((pud_t *)2); })
  66 #define pud_free(mm, x)                         do { } while (0)
  67
  68 #define pmd_alloc_one(mm,address)               ({ BUG(); ((pmd_t *)2); })
  69 #define pmd_free(mm, x)                         do { } while (0)
  70
  71 #define pgd_populate(mm, pgd, pud)              BUG()
  72 #define pgd_populate_kernel(mm, pgd, pud)       BUG()
  73
  74 #define pud_populate(mm, pud, pmd)              BUG()
  75 #define pud_populate_kernel(mm, pud, pmd)       BUG()
  76
  77 #else /* __s390x__ */
  78
  79 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  80 {
  81         if (mm->context.asce_limit <= (1UL << 31))
  82                 return _SEGMENT_ENTRY_EMPTY;
  83         if (mm->context.asce_limit <= (1UL << 42))
  84                 return _REGION3_ENTRY_EMPTY;
  85         return _REGION2_ENTRY_EMPTY;
  86 }
  87
  88 int crst_table_upgrade(struct mm_struct *, unsigned long limit);
  89 void crst_table_downgrade(struct mm_struct *, unsigned long limit);
  90
  91 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
  92 {
  93         unsigned long *table = crst_table_alloc(mm, mm->context.noexec);
  94         if (table)
  95                 crst_table_init(table, _REGION3_ENTRY_EMPTY);
  96         return (pud_t *) table;
  97 }
  98 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
  99
 100 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
 101 {
 102         unsigned long *table = crst_table_alloc(mm, mm->context.noexec);
 103         if (table)
 104                 crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
 105         return (pmd_t *) table;
 106 }
 107 #define pmd_free(mm, pmd) crst_table_free(mm, (unsigned long *) pmd)
 108
 109 static inline void pgd_populate_kernel(struct mm_struct *mm,
 110                                        pgd_t *pgd, pud_t *pud)
 111 {
 112         pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
 113 }
 114
 115 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 116 {
 117         pgd_populate_kernel(mm, pgd, pud);
 118         if (mm->context.noexec) {
 119                 pgd = get_shadow_table(pgd);
 120                 pud = get_shadow_table(pud);
 121                 pgd_populate_kernel(mm, pgd, pud);
 122         }
 123 }
 124
 125 static inline void pud_populate_kernel(struct mm_struct *mm,
 126                                        pud_t *pud, pmd_t *pmd)
 127 {
 128         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
 129 }
 130
 131 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 132 {
 133         pud_populate_kernel(mm, pud, pmd);
 134         if (mm->context.noexec) {
 135                 pud = get_shadow_table(pud);
 136                 pmd = get_shadow_table(pmd);
 137                 pud_populate_kernel(mm, pud, pmd);
 138         }
 139 }
 140
 141 #endif /* __s390x__ */
 142
 143 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 144 {
 145         spin_lock_init(&mm->context.list_lock);
 146         INIT_LIST_HEAD(&mm->context.crst_list);
 147         INIT_LIST_HEAD(&mm->context.pgtable_list);
 148         return (pgd_t *)
 149                 crst_table_alloc(mm, user_mode == SECONDARY_SPACE_MODE);
 150 }
 151 #define pgd_free(mm, pgd) crst_table_free(mm, (unsigned long *) pgd)
 152
 153 static inline void pmd_populate_kernel(struct mm_struct *mm,
 154                                        pmd_t *pmd, pte_t *pte)
 155 {
 156         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 157 }
 158
 159 static inline void pmd_populate(struct mm_struct *mm,
 160                                 pmd_t *pmd, pgtable_t pte)
 161 {
 162         pmd_populate_kernel(mm, pmd, pte);
 163         if (mm->context.noexec) {
 164                 pmd = get_shadow_table(pmd);
 165                 pmd_populate_kernel(mm, pmd, pte + PTRS_PER_PTE);
 166         }
 167 }
 168
 169 #define pmd_pgtable(pmd) \
 170         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 171
 172 /*
 173  * page table entry allocation/free routines.
 174  */
 175 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 176 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 177
 178 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 179 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 180
 181 extern void rcu_table_freelist_finish(void);
 182
 183 #endif /* _S390_PGALLOC_H */