/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, unsigned long addr,
25		      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
61/*
62 * This function checks for proper alignment of input addr and len parameters.
63 */
64int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
65{
66	if (len & ~HPAGE_MASK)
67		return -EINVAL;
68	if (addr & ~HPAGE_MASK)
69		return -EINVAL;
70	return 0;
71}
72
73int pmd_huge(pmd_t pmd)
74{
75	return (pmd_val(pmd) & _PAGE_HUGE) != 0;
76}
77
78int pud_huge(pud_t pud)
79{
80	return (pud_val(pud) & _PAGE_HUGE) != 0;
81}