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
  25 unsigned long *page_table_alloc(struct mm_struct *);
  26 void page_table_free(struct mm_struct *, unsigned long *);
  27 void disable_noexec(struct mm_struct *, struct task_struct *);
  28
  29 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
  30 {
  31         typedef struct { char _[n]; } addrtype;
  32
  33         *s = val;
  34         n = (n / 256) - 1;
  35         asm volatile(
  36 #ifdef CONFIG_64BIT
  37                 "       mvc     8(248,%0),0(%0)\n"
  38 #else
  39                 "       mvc     4(252,%0),0(%0)\n"
  40 #endif
  41                 "0:     mvc     256(256,%0),0(%0)\n"
  42                 "       la      %0,256(%0)\n"
  43                 "       brct    %1,0b\n"
  44                 : "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
  45                 : "m" (*(addrtype *) s));
  46 }
  47
  48 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  49 {
  50         clear_table(crst, entry, sizeof(unsigned long)*2048);
  51         crst = get_shadow_table(crst);
  52         if (crst)
  53                 clear_table(crst, entry, sizeof(unsigned long)*2048);
  54 }
  55
  56 #ifndef __s390x__
  57
  58 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  59 {
  60         return _SEGMENT_ENTRY_EMPTY;
  61 }
  62
  63 #define pud_alloc_one(mm,address)               ({ BUG(); ((pud_t *)2); })
  64 #define pud_free(mm, x)                         do { } while (0)
  65
  66 #define pmd_alloc_one(mm,address)               ({ BUG(); ((pmd_t *)2); })
  67 #define pmd_free(mm, x)                         do { } while (0)
  68
  69 #define pgd_populate(mm, pgd, pud)              BUG()
  70 #define pgd_populate_kernel(mm, pgd, pud)       BUG()
  71
  72 #define pud_populate(mm, pud, pmd)              BUG()
  73 #define pud_populate_kernel(mm, pud, pmd)       BUG()
  74
  75 #else /* __s390x__ */
  76
  77 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  78 {
  79         if (mm->context.asce_limit <= (1UL << 31))
  80                 return _SEGMENT_ENTRY_EMPTY;
  81         if (mm->context.asce_limit <= (1UL << 42))
  82                 return _REGION3_ENTRY_EMPTY;
  83         return _REGION2_ENTRY_EMPTY;
  84 }
  85
  86 int crst_table_upgrade(struct mm_struct *, unsigned long limit);
  87 void crst_table_downgrade(struct mm_struct *, unsigned long limit);
  88
  89 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
  90 {
  91         unsigned long *table = crst_table_alloc(mm, mm->context.noexec);
  92         if (table)
  93                 crst_table_init(table, _REGION3_ENTRY_EMPTY);
  94         return (pud_t *) table;
  95 }
  96 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
  97
  98 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  99 {
 100         unsigned long *table = crst_table_alloc(mm, mm->context.noexec);
 101         if (table)
 102                 crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
 103         return (pmd_t *) table;
 104 }
 105 #define pmd_free(mm, pmd) crst_table_free(mm, (unsigned long *) pmd)
 106
 107 static inline void pgd_populate_kernel(struct mm_struct *mm,
 108                                        pgd_t *pgd, pud_t *pud)
 109 {
 110         pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
 111 }
 112
 113 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 114 {
 115         pgd_populate_kernel(mm, pgd, pud);
 116         if (mm->context.noexec) {
 117                 pgd = get_shadow_table(pgd);
 118                 pud = get_shadow_table(pud);
 119                 pgd_populate_kernel(mm, pgd, pud);
 120         }
 121 }
 122
 123 static inline void pud_populate_kernel(struct mm_struct *mm,
 124                                        pud_t *pud, pmd_t *pmd)
 125 {
 126         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
 127 }
 128
 129 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 130 {
 131         pud_populate_kernel(mm, pud, pmd);
 132         if (mm->context.noexec) {
 133                 pud = get_shadow_table(pud);
 134                 pmd = get_shadow_table(pmd);
 135                 pud_populate_kernel(mm, pud, pmd);
 136         }
 137 }
 138
 139 #endif /* __s390x__ */
 140
 141 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 142 {
 143         spin_lock_init(&mm->context.list_lock);
 144         INIT_LIST_HEAD(&mm->context.crst_list);
 145         INIT_LIST_HEAD(&mm->context.pgtable_list);
 146         return (pgd_t *) crst_table_alloc(mm, s390_noexec);
 147 }
 148 #define pgd_free(mm, pgd) crst_table_free(mm, (unsigned long *) pgd)
 149
 150 static inline void pmd_populate_kernel(struct mm_struct *mm,
 151                                        pmd_t *pmd, pte_t *pte)
 152 {
 153         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 154 }
 155
 156 static inline void pmd_populate(struct mm_struct *mm,
 157                                 pmd_t *pmd, pgtable_t pte)
 158 {
 159         pmd_populate_kernel(mm, pmd, pte);
 160         if (mm->context.noexec) {
 161                 pmd = get_shadow_table(pmd);
 162                 pmd_populate_kernel(mm, pmd, pte + PTRS_PER_PTE);
 163         }
 164 }
 165
 166 #define pmd_pgtable(pmd) \
 167         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 168
 169 /*
 170  * page table entry allocation/free routines.
 171  */
 172 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 173 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 174
 175 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 176 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 177
 178 #endif /* _S390_PGALLOC_H */