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 extern void diag10(unsigned long addr);
  23
  24 /*
  25  * Page allocation orders.
  26  */
  27 #ifndef __s390x__
  28 # define PTE_ALLOC_ORDER        0
  29 # define PMD_ALLOC_ORDER        0
  30 # define PGD_ALLOC_ORDER        1
  31 #else /* __s390x__ */
  32 # define PTE_ALLOC_ORDER        0
  33 # define PMD_ALLOC_ORDER        2
  34 # define PGD_ALLOC_ORDER        2
  35 #endif /* __s390x__ */
  36
  37 /*
  38  * Allocate and free page tables. The xxx_kernel() versions are
  39  * used to allocate a kernel page table - this turns on ASN bits
  40  * if any.
  41  */
  42
  43 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  44 {
  45         pgd_t *pgd = (pgd_t *) __get_free_pages(GFP_KERNEL, PGD_ALLOC_ORDER);
  46         int i;
  47
  48         if (!pgd)
  49                 return NULL;
  50         if (s390_noexec) {
  51                 pgd_t *shadow_pgd = (pgd_t *)
  52                         __get_free_pages(GFP_KERNEL, PGD_ALLOC_ORDER);
  53                 struct page *page = virt_to_page(pgd);
  54
  55                 if (!shadow_pgd) {
  56                         free_pages((unsigned long) pgd, PGD_ALLOC_ORDER);
  57                         return NULL;
  58                 }
  59                 page->lru.next = (void *) shadow_pgd;
  60         }
  61         for (i = 0; i < PTRS_PER_PGD; i++)
  62 #ifndef __s390x__
  63                 pmd_clear(pmd_offset(pgd + i, i*PGDIR_SIZE));
  64 #else
  65                 pgd_clear(pgd + i);
  66 #endif
  67         return pgd;
  68 }
  69
  70 static inline void pgd_free(pgd_t *pgd)
  71 {
  72         pgd_t *shadow_pgd = get_shadow_pgd(pgd);
  73
  74         if (shadow_pgd)
  75                 free_pages((unsigned long) shadow_pgd, PGD_ALLOC_ORDER);
  76         free_pages((unsigned long) pgd, PGD_ALLOC_ORDER);
  77 }
  78
  79 #ifndef __s390x__
  80 /*
  81  * page middle directory allocation/free routines.
  82  * We use pmd cache only on s390x, so these are dummy routines. This
  83  * code never triggers because the pgd will always be present.
  84  */
  85 #define pmd_alloc_one(mm,address)       ({ BUG(); ((pmd_t *)2); })
  86 #define pmd_free(x)                     do { } while (0)
  87 #define __pmd_free_tlb(tlb,x)           do { } while (0)
  88 #define pgd_populate(mm, pmd, pte)      BUG()
  89 #define pgd_populate_kernel(mm, pmd, pte)       BUG()
  90 #else /* __s390x__ */
  91 static inline pmd_t * pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
  92 {
  93         pmd_t *pmd = (pmd_t *) __get_free_pages(GFP_KERNEL, PMD_ALLOC_ORDER);
  94         int i;
  95
  96         if (!pmd)
  97                 return NULL;
  98         if (s390_noexec) {
  99                 pmd_t *shadow_pmd = (pmd_t *)
 100                         __get_free_pages(GFP_KERNEL, PMD_ALLOC_ORDER);
 101                 struct page *page = virt_to_page(pmd);
 102
 103                 if (!shadow_pmd) {
 104                         free_pages((unsigned long) pmd, PMD_ALLOC_ORDER);
 105                         return NULL;
 106                 }
 107                 page->lru.next = (void *) shadow_pmd;
 108         }
 109         for (i=0; i < PTRS_PER_PMD; i++)
 110                 pmd_clear(pmd + i);
 111         return pmd;
 112 }
 113
 114 static inline void pmd_free (pmd_t *pmd)
 115 {
 116         pmd_t *shadow_pmd = get_shadow_pmd(pmd);
 117
 118         if (shadow_pmd)
 119                 free_pages((unsigned long) shadow_pmd, PMD_ALLOC_ORDER);
 120         free_pages((unsigned long) pmd, PMD_ALLOC_ORDER);
 121 }
 122
 123 #define __pmd_free_tlb(tlb,pmd)                 \
 124         do {                                    \
 125                 tlb_flush_mmu(tlb, 0, 0);       \
 126                 pmd_free(pmd);                  \
 127          } while (0)
 128
 129 static inline void
 130 pgd_populate_kernel(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmd)
 131 {
 132         pgd_val(*pgd) = _PGD_ENTRY | __pa(pmd);
 133 }
 134
 135 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pmd_t *pmd)
 136 {
 137         pgd_t *shadow_pgd = get_shadow_pgd(pgd);
 138         pmd_t *shadow_pmd = get_shadow_pmd(pmd);
 139
 140         if (shadow_pgd && shadow_pmd)
 141                 pgd_populate_kernel(mm, shadow_pgd, shadow_pmd);
 142         pgd_populate_kernel(mm, pgd, pmd);
 143 }
 144
 145 #endif /* __s390x__ */
 146
 147 static inline void
 148 pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
 149 {
 150 #ifndef __s390x__
 151         pmd_val(pmd[0]) = _PAGE_TABLE + __pa(pte);
 152         pmd_val(pmd[1]) = _PAGE_TABLE + __pa(pte+256);
 153         pmd_val(pmd[2]) = _PAGE_TABLE + __pa(pte+512);
 154         pmd_val(pmd[3]) = _PAGE_TABLE + __pa(pte+768);
 155 #else /* __s390x__ */
 156         pmd_val(*pmd) = _PMD_ENTRY + __pa(pte);
 157         pmd_val1(*pmd) = _PMD_ENTRY + __pa(pte+256);
 158 #endif /* __s390x__ */
 159 }
 160
 161 static inline void
 162 pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *page)
 163 {
 164         pte_t *pte = (pte_t *)page_to_phys(page);
 165         pmd_t *shadow_pmd = get_shadow_pmd(pmd);
 166         pte_t *shadow_pte = get_shadow_pte(pte);
 167
 168         pmd_populate_kernel(mm, pmd, pte);
 169         if (shadow_pmd && shadow_pte)
 170                 pmd_populate_kernel(mm, shadow_pmd, shadow_pte);
 171 }
 172
 173 /*
 174  * page table entry allocation/free routines.
 175  */
 176 static inline pte_t *
 177 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long vmaddr)
 178 {
 179         pte_t *pte = (pte_t *) __get_free_page(GFP_KERNEL|__GFP_REPEAT);
 180         int i;
 181
 182         if (!pte)
 183                 return NULL;
 184         if (s390_noexec) {
 185                 pte_t *shadow_pte = (pte_t *)
 186                         __get_free_page(GFP_KERNEL|__GFP_REPEAT);
 187                 struct page *page = virt_to_page(pte);
 188
 189                 if (!shadow_pte) {
 190                         free_page((unsigned long) pte);
 191                         return NULL;
 192                 }
 193                 page->lru.next = (void *) shadow_pte;
 194         }
 195         for (i=0; i < PTRS_PER_PTE; i++) {
 196                 pte_clear(mm, vmaddr, pte + i);
 197                 vmaddr += PAGE_SIZE;
 198         }
 199         return pte;
 200 }
 201
 202 static inline struct page *
 203 pte_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
 204 {
 205         pte_t *pte = pte_alloc_one_kernel(mm, vmaddr);
 206         if (pte)
 207                 return virt_to_page(pte);
 208         return NULL;
 209 }
 210
 211 static inline void pte_free_kernel(pte_t *pte)
 212 {
 213         pte_t *shadow_pte = get_shadow_pte(pte);
 214
 215         if (shadow_pte)
 216                 free_page((unsigned long) shadow_pte);
 217         free_page((unsigned long) pte);
 218 }
 219
 220 static inline void pte_free(struct page *pte)
 221 {
 222         struct page *shadow_page = get_shadow_page(pte);
 223
 224         if (shadow_page)
 225                 __free_page(shadow_page);
 226         __free_page(pte);
 227 }
 228
 229 #define __pte_free_tlb(tlb, pte)                                        \
 230 ({                                                                      \
 231         struct mmu_gather *__tlb = (tlb);                               \
 232         struct page *__pte = (pte);                                     \
 233         struct page *shadow_page = get_shadow_page(__pte);              \
 234         if (shadow_page)                                                \
 235                 tlb_remove_page(__tlb, shadow_page);                    \
 236         tlb_remove_page(__tlb, __pte);                                  \
 237 })
 238
 239 #endif /* _S390_PGALLOC_H */