arch/sh64/mm/hugetlbpage.c

   1 /*
   2  * arch/sh64/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         pmd_t *pmd;
  29         pte_t *pte = NULL;
  30
  31         pgd = pgd_offset(mm, addr);
  32         if (pgd) {
  33                 pmd = pmd_alloc(mm, pgd, addr);
  34                 if (pmd)
  35                         pte = pte_alloc_map(mm, pmd, addr);
  36         }
  37         return pte;
  38 }
  39
  40 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
  41 {
  42         pgd_t *pgd;
  43         pmd_t *pmd;
  44         pte_t *pte = NULL;
  45
  46         pgd = pgd_offset(mm, addr);
  47         if (pgd) {
  48                 pmd = pmd_offset(pgd, addr);
  49                 if (pmd)
  50                         pte = pte_offset_map(pmd, addr);
  51         }
  52         return pte;
  53 }
  54
  55 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
  56 {
  57         return 0;
  58 }
  59
  60 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
  61                      pte_t *ptep, pte_t entry)
  62 {
  63         int i;
  64
  65         for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
  66                 set_pte_at(mm, addr, ptep, entry);
  67                 ptep++;
  68                 addr += PAGE_SIZE;
  69                 pte_val(entry) += PAGE_SIZE;
  70         }
  71 }
  72
  73 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
  74                               pte_t *ptep)
  75 {
  76         pte_t entry;
  77         int i;
  78
  79         entry = *ptep;
  80
  81         for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
  82                 pte_clear(mm, addr, ptep);
  83                 addr += PAGE_SIZE;
  84                 ptep++;
  85         }
  86
  87         return entry;
  88 }
  89
  90 struct page *follow_huge_addr(struct mm_struct *mm,
  91                               unsigned long address, int write)
  92 {
  93         return ERR_PTR(-EINVAL);
  94 }
  95
  96 int pmd_huge(pmd_t pmd)
  97 {
  98         return 0;
  99 }
 100
 101 struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
 102                              pmd_t *pmd, int write)
 103 {
 104         return NULL;
 105 }