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
  24 pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr,
  25                       unsigned long sz)
  26 {
  27         pgd_t *pgd;
  28         pud_t *pud;
  29         pte_t *pte = NULL;
  30
  31         pgd = pgd_offset(mm, addr);
  32         pud = pud_alloc(mm, pgd, addr);
  33         if (pud)
  34                 pte = (pte_t *)pmd_alloc(mm, pud, addr);
  35
  36         return pte;
  37 }
  38
  39 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
  40                        unsigned long sz)
  41 {
  42         pgd_t *pgd;
  43         pud_t *pud;
  44         pmd_t *pmd = NULL;
  45
  46         pgd = pgd_offset(mm, addr);
  47         if (pgd_present(*pgd)) {
  48                 pud = pud_offset(pgd, addr);
  49                 if (pud_present(*pud))
  50                         pmd = pmd_offset(pud, addr);
  51         }
  52         return (pte_t *) pmd;
  53 }
  54
  55 /*
  56  * This function checks for proper alignment of input addr and len parameters.
  57  */
  58 int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
  59 {
  60         if (len & ~HPAGE_MASK)
  61                 return -EINVAL;
  62         if (addr & ~HPAGE_MASK)
  63                 return -EINVAL;
  64         return 0;
  65 }
  66
  67 int pmd_huge(pmd_t pmd)
  68 {
  69         return (pmd_val(pmd) & _PAGE_HUGE) != 0;
  70 }
  71
  72 int pud_huge(pud_t pud)
  73 {
  74         return (pud_val(pud) & _PAGE_HUGE) != 0;
  75 }