arch/sh/mm/hugetlbpage.c

   1 /*
   2  * arch/sh/mm/hugetlbpage.c
   3  *
   4  * SuperH HugeTLB page support.
   5  *
   6  * Cloned from sparc64 by Paul Mundt.
   7  *
   8  * Copyright (C) 2002, 2003 David S. Miller (davem@redhat.com)
   9  */
  10
  11 #include <linux/init.h>
  12 #include <linux/fs.h>
  13 #include <linux/mm.h>
  14 #include <linux/hugetlb.h>
  15 #include <linux/pagemap.h>
  16 #include <linux/slab.h>
  17 #include <linux/sysctl.h>
  18
  19 #include <asm/mman.h>
  20 #include <asm/pgalloc.h>
  21 #include <asm/tlb.h>
  22 #include <asm/tlbflush.h>
  23 #include <asm/cacheflush.h>
  24
  25 pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
  26 {
  27         pgd_t *pgd;
  28         pud_t *pud;
  29         pmd_t *pmd;
  30         pte_t *pte = NULL;
  31
  32         pgd = pgd_offset(mm, addr);
  33         if (pgd) {
  34                 pud = pud_alloc(mm, pgd, addr);
  35                 if (pud) {
  36                         pmd = pmd_alloc(mm, pud, addr);
  37                         if (pmd)
  38                                 pte = pte_alloc_map(mm, pmd, addr);
  39                 }
  40         }
  41
  42         return pte;
  43 }
  44
  45 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
  46 {
  47         pgd_t *pgd;
  48         pud_t *pud;
  49         pmd_t *pmd;
  50         pte_t *pte = NULL;
  51
  52         pgd = pgd_offset(mm, addr);
  53         if (pgd) {
  54                 pud = pud_offset(pgd, addr);
  55                 if (pud) {
  56                         pmd = pmd_offset(pud, addr);
  57                         if (pmd)
  58                                 pte = pte_offset_map(pmd, addr);
  59                 }
  60         }
  61
  62         return pte;
  63 }
  64
  65 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
  66 {
  67         return 0;
  68 }
  69
  70 struct page *follow_huge_addr(struct mm_struct *mm,
  71                               unsigned long address, int write)
  72 {
  73         return ERR_PTR(-EINVAL);
  74 }
  75
  76 int pmd_huge(pmd_t pmd)
  77 {
  78         return 0;
  79 }
  80
  81 struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
  82                              pmd_t *pmd, int write)
  83 {
  84         return NULL;
  85 }