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