xref: /openbmc/linux/arch/arm/mm/hugetlbpage.c (revision 0da85d1e)
1 /*
2  * arch/arm/mm/hugetlbpage.c
3  *
4  * Copyright (C) 2012 ARM Ltd.
5  *
6  * Based on arch/x86/include/asm/hugetlb.h and Bill Carson's patches
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20  */
21 
22 #include <linux/init.h>
23 #include <linux/fs.h>
24 #include <linux/mm.h>
25 #include <linux/hugetlb.h>
26 #include <linux/pagemap.h>
27 #include <linux/err.h>
28 #include <linux/sysctl.h>
29 #include <asm/mman.h>
30 #include <asm/tlb.h>
31 #include <asm/tlbflush.h>
32 #include <asm/pgalloc.h>
33 
34 /*
35  * On ARM, huge pages are backed by pmd's rather than pte's, so we do a lot
36  * of type casting from pmd_t * to pte_t *.
37  */
38 
39 int pud_huge(pud_t pud)
40 {
41 	return 0;
42 }
43 
44 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
45 {
46 	return 0;
47 }
48 
49 int pmd_huge(pmd_t pmd)
50 {
51 	return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
52 }
53