blob: a7fee0dfb7a9daaeb67616804f00cac7365d778f [file] [log] [blame]
David Daney50a41ff2009-05-27 17:47:42 -07001/*
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/init.h>
15#include <linux/fs.h>
16#include <linux/mm.h>
17#include <linux/hugetlb.h>
18#include <linux/pagemap.h>
David Daney50a41ff2009-05-27 17:47:42 -070019#include <linux/err.h>
20#include <linux/sysctl.h>
21#include <asm/mman.h>
22#include <asm/tlb.h>
23#include <asm/tlbflush.h>
24
25pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr,
26 unsigned long sz)
27{
28 pgd_t *pgd;
29 pud_t *pud;
30 pte_t *pte = NULL;
31
32 pgd = pgd_offset(mm, addr);
33 pud = pud_alloc(mm, pgd, addr);
34 if (pud)
35 pte = (pte_t *)pmd_alloc(mm, pud, addr);
36
37 return pte;
38}
39
40pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
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
55int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
56{
57 return 0;
58}
59
60/*
61 * This function checks for proper alignment of input addr and len parameters.
62 */
63int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
64{
65 if (len & ~HPAGE_MASK)
66 return -EINVAL;
67 if (addr & ~HPAGE_MASK)
68 return -EINVAL;
69 return 0;
70}
71
72struct page *
73follow_huge_addr(struct mm_struct *mm, unsigned long address, int write)
74{
75 return ERR_PTR(-EINVAL);
76}
77
78int pmd_huge(pmd_t pmd)
79{
80 return (pmd_val(pmd) & _PAGE_HUGE) != 0;
81}
82
83int pud_huge(pud_t pud)
84{
85 return (pud_val(pud) & _PAGE_HUGE) != 0;
86}
87
88struct page *
89follow_huge_pmd(struct mm_struct *mm, unsigned long address,
90 pmd_t *pmd, int write)
91{
92 struct page *page;
93
94 page = pte_page(*(pte_t *)pmd);
95 if (page)
96 page += ((address & ~HPAGE_MASK) >> PAGE_SHIFT);
97 return page;
98}