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/smp_lock.h>
  17 #include <linux/slab.h>
  18 #include <linux/sysctl.h>
  19
  20 #include <asm/mman.h>
  21 #include <asm/pgalloc.h>
  22 #include <asm/tlb.h>
  23 #include <asm/tlbflush.h>
  24 #include <asm/cacheflush.h>
  25
  26 pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
  27 {
  28         pgd_t *pgd;
  29         pmd_t *pmd;
  30         pte_t *pte = NULL;
  31
  32         pgd = pgd_offset(mm, addr);
  33         if (pgd) {
  34                 pmd = pmd_alloc(mm, pgd, addr);
  35                 if (pmd)
  36                         pte = pte_alloc_map(mm, pmd, addr);
  37         }
  38         return pte;
  39 }
  40
  41 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
  42 {
  43         pgd_t *pgd;
  44         pmd_t *pmd;
  45         pte_t *pte = NULL;
  46
  47         pgd = pgd_offset(mm, addr);
  48         if (pgd) {
  49                 pmd = pmd_offset(pgd, addr);
  50                 if (pmd)
  51                         pte = pte_offset_map(pmd, addr);
  52         }
  53         return pte;
  54 }
  55
  56 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
  57 {
  58         return 0;
  59 }
  60
  61 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
  62                      pte_t *ptep, pte_t entry)
  63 {
  64         int i;
  65
  66         for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
  67                 set_pte_at(mm, addr, ptep, entry);
  68                 ptep++;
  69                 addr += PAGE_SIZE;
  70                 pte_val(entry) += PAGE_SIZE;
  71         }
  72 }
  73
  74 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
  75                               pte_t *ptep)
  76 {
  77         pte_t entry;
  78         int i;
  79
  80         entry = *ptep;
  81
  82         for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
  83                 pte_clear(mm, addr, ptep);
  84                 addr += PAGE_SIZE;
  85                 ptep++;
  86         }
  87
  88         return entry;
  89 }
  90
  91 struct page *follow_huge_addr(struct mm_struct *mm,
  92                               unsigned long address, int write)
  93 {
  94         return ERR_PTR(-EINVAL);
  95 }
  96
  97 int pmd_huge(pmd_t pmd)
  98 {
  99         return 0;
 100 }
 101
 102 struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
 103                              pmd_t *pmd, int write)
 104 {
 105         return NULL;
 106 }