xref: /openbmc/linux/arch/arm64/mm/hugetlbpage.c (revision 9cfc5c90)
1 /*
2  * arch/arm64/mm/hugetlbpage.c
3  *
4  * Copyright (C) 2013 Linaro Ltd.
5  *
6  * Based on arch/x86/mm/hugetlbpage.c.
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 
18 #include <linux/init.h>
19 #include <linux/fs.h>
20 #include <linux/mm.h>
21 #include <linux/hugetlb.h>
22 #include <linux/pagemap.h>
23 #include <linux/err.h>
24 #include <linux/sysctl.h>
25 #include <asm/mman.h>
26 #include <asm/tlb.h>
27 #include <asm/tlbflush.h>
28 #include <asm/pgalloc.h>
29 
30 int pmd_huge(pmd_t pmd)
31 {
32 	return pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT);
33 }
34 
35 int pud_huge(pud_t pud)
36 {
37 #ifndef __PAGETABLE_PMD_FOLDED
38 	return pud_val(pud) && !(pud_val(pud) & PUD_TABLE_BIT);
39 #else
40 	return 0;
41 #endif
42 }
43 
44 static __init int setup_hugepagesz(char *opt)
45 {
46 	unsigned long ps = memparse(opt, &opt);
47 	if (ps == PMD_SIZE) {
48 		hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT);
49 	} else if (ps == PUD_SIZE) {
50 		hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT);
51 	} else {
52 		pr_err("hugepagesz: Unsupported page size %lu M\n", ps >> 20);
53 		return 0;
54 	}
55 	return 1;
56 }
57 __setup("hugepagesz=", setup_hugepagesz);
58