LXR linux/arch/mips/mm/hugetlbpage.c

   1/*
   2 * MIPS Huge TLB Page Support for Kernel.
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
   9 * Copyright 2005, Embedded Alley Solutions, Inc.
  10 * Matt Porter <mporter@embeddedalley.com>
  11 * Copyright (C) 2008, 2009 Cavium Networks, Inc.
  12 */
  13
  14#include <linux/fs.h>
  15#include <linux/mm.h>
  16#include <linux/hugetlb.h>
  17#include <linux/pagemap.h>
  18#include <linux/err.h>
  19#include <linux/sysctl.h>
  20#include <asm/mman.h>
  21#include <asm/tlb.h>
  22#include <asm/tlbflush.h>
  23
  24pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
  25                      unsigned long addr, unsigned long sz)
  26{
  27        pgd_t *pgd;
  28        p4d_t *p4d;
  29        pud_t *pud;
  30        pte_t *pte = NULL;
  31
  32        pgd = pgd_offset(mm, addr);
  33        p4d = p4d_alloc(mm, pgd, addr);
  34        pud = pud_alloc(mm, p4d, addr);
  35        if (pud)
  36                pte = (pte_t *)pmd_alloc(mm, pud, addr);
  37
  38        return pte;
  39}
  40
  41pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
  42                       unsigned long sz)
  43{
  44        pgd_t *pgd;
  45        p4d_t *p4d;
  46        pud_t *pud;
  47        pmd_t *pmd = NULL;
  48
  49        pgd = pgd_offset(mm, addr);
  50        if (pgd_present(*pgd)) {
  51                p4d = p4d_offset(pgd, addr);
  52                if (p4d_present(*p4d)) {
  53                        pud = pud_offset(p4d, addr);
  54                        if (pud_present(*pud))
  55                                pmd = pmd_offset(pud, addr);
  56                }
  57        }
  58        return (pte_t *) pmd;
  59}
  60
  61int pmd_huge(pmd_t pmd)
  62{
  63        return (pmd_val(pmd) & _PAGE_HUGE) != 0;
  64}
  65
  66int pud_huge(pud_t pud)
  67{
  68        return (pud_val(pud) & _PAGE_HUGE) != 0;
  69}
  70