include/asm-s390/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         *s = val;
  32         n = (n / 256) - 1;
  33         asm volatile(
  34 #ifdef CONFIG_64BIT
  35                 "       mvc     8(248,%0),0(%0)\n"
  36 #else
  37                 "       mvc     4(252,%0),0(%0)\n"
  38 #endif
  39                 "0:     mvc     256(256,%0),0(%0)\n"
  40                 "       la      %0,256(%0)\n"
  41                 "       brct    %1,0b\n"
  42                 : "+a" (s), "+d" (n));
  43 }
  44
  45 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
  46 {
  47         clear_table(crst, entry, sizeof(unsigned long)*2048);
  48         crst = get_shadow_table(crst);
  49         if (crst)
  50                 clear_table(crst, entry, sizeof(unsigned long)*2048);
  51 }
  52
  53 #ifndef __s390x__
  54
  55 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  56 {
  57         return _SEGMENT_ENTRY_EMPTY;
  58 }
  59
  60 #define pud_alloc_one(mm,address)               ({ BUG(); ((pud_t *)2); })
  61 #define pud_free(mm, x)                         do { } while (0)
  62
  63 #define pmd_alloc_one(mm,address)               ({ BUG(); ((pmd_t *)2); })
  64 #define pmd_free(mm, x)                         do { } while (0)
  65
  66 #define pgd_populate(mm, pgd, pud)              BUG()
  67 #define pgd_populate_kernel(mm, pgd, pud)       BUG()
  68
  69 #define pud_populate(mm, pud, pmd)              BUG()
  70 #define pud_populate_kernel(mm, pud, pmd)       BUG()
  71
  72 #else /* __s390x__ */
  73
  74 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
  75 {
  76         return _REGION2_ENTRY_EMPTY;
  77 }
  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, mm->context.noexec);
  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, mm->context.noexec);
  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_kernel(struct mm_struct *mm,
  98                                        pgd_t *pgd, pud_t *pud)
  99 {
 100         pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
 101 }
 102
 103 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 104 {
 105         pgd_t *shadow_pgd = get_shadow_table(pgd);
 106         pud_t *shadow_pud = get_shadow_table(pud);
 107
 108         if (shadow_pgd && shadow_pud)
 109                 pgd_populate_kernel(mm, shadow_pgd, shadow_pud);
 110         pgd_populate_kernel(mm, pgd, pud);
 111 }
 112
 113 static inline void pud_populate_kernel(struct mm_struct *mm,
 114                                        pud_t *pud, pmd_t *pmd)
 115 {
 116         pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
 117 }
 118
 119 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 120 {
 121         pud_populate_kernel(mm, pud, pmd);
 122         if (mm->context.noexec) {
 123                 pud = get_shadow_table(pud);
 124                 pmd = get_shadow_table(pmd);
 125                 pud_populate_kernel(mm, pud, pmd);
 126         }
 127 }
 128
 129 #endif /* __s390x__ */
 130
 131 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 132 {
 133         unsigned long *crst;
 134
 135         INIT_LIST_HEAD(&mm->context.crst_list);
 136         INIT_LIST_HEAD(&mm->context.pgtable_list);
 137         crst = crst_table_alloc(mm, s390_noexec);
 138         if (crst)
 139                 crst_table_init(crst, pgd_entry_type(mm));
 140         return (pgd_t *) crst;
 141 }
 142 #define pgd_free(mm, pgd) crst_table_free(mm, (unsigned long *) pgd)
 143
 144 static inline void pmd_populate_kernel(struct mm_struct *mm,
 145                                        pmd_t *pmd, pte_t *pte)
 146 {
 147         pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
 148 }
 149
 150 static inline void pmd_populate(struct mm_struct *mm,
 151                                 pmd_t *pmd, pgtable_t pte)
 152 {
 153         pmd_populate_kernel(mm, pmd, pte);
 154         if (mm->context.noexec) {
 155                 pmd = get_shadow_table(pmd);
 156                 pmd_populate_kernel(mm, pmd, pte + PTRS_PER_PTE);
 157         }
 158 }
 159
 160 #define pmd_pgtable(pmd) \
 161         (pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
 162
 163 /*
 164  * page table entry allocation/free routines.
 165  */
 166 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 167 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
 168
 169 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
 170 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
 171
 172 #endif /* _S390_PGALLOC_H */