xref: /openbmc/linux/arch/sh/mm/hugetlbpage.c (revision 64c70b1c) 
1 /*
2  * arch/sh/mm/hugetlbpage.c
3  *
4  * SuperH HugeTLB page support.
5  *
6  * Cloned from sparc64 by Paul Mundt.
7  *
8  * Copyright (C) 2002, 2003 David S. Miller (davem@redhat.com)
9  */
10 
11 #include <linux/init.h>
12 #include <linux/fs.h>
13 #include <linux/mm.h>
14 #include <linux/hugetlb.h>
15 #include <linux/pagemap.h>
16 #include <linux/slab.h>
17 #include <linux/sysctl.h>
18 
19 #include <asm/mman.h>
20 #include <asm/pgalloc.h>
21 #include <asm/tlb.h>
22 #include <asm/tlbflush.h>
23 #include <asm/cacheflush.h>
24 
25 pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
26 {
27 	pgd_t *pgd;
28 	pud_t *pud;
29 	pmd_t *pmd;
30 	pte_t *pte = NULL;
31 
32 	pgd = pgd_offset(mm, addr);
33 	if (pgd) {
34 		pud = pud_alloc(mm, pgd, addr);
35 		if (pud) {
36 			pmd = pmd_alloc(mm, pud, addr);
37 			if (pmd)
38 				pte = pte_alloc_map(mm, pmd, addr);
39 		}
40 	}
41 
42 	return pte;
43 }
44 
45 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
46 {
47 	pgd_t *pgd;
48 	pud_t *pud;
49 	pmd_t *pmd;
50 	pte_t *pte = NULL;
51 
52 	pgd = pgd_offset(mm, addr);
53 	if (pgd) {
54 		pud = pud_offset(pgd, addr);
55 		if (pud) {
56 			pmd = pmd_offset(pud, addr);
57 			if (pmd)
58 				pte = pte_offset_map(pmd, addr);
59 		}
60 	}
61 
62 	return pte;
63 }
64 
65 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
66 {
67 	return 0;
68 }
69 
70 struct page *follow_huge_addr(struct mm_struct *mm,
71 			      unsigned long address, int write)
72 {
73 	return ERR_PTR(-EINVAL);
74 }
75 
76 int pmd_huge(pmd_t pmd)
77 {
78 	return 0;
79 }
80 
81 struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
82 			     pmd_t *pmd, int write)
83 {
84 	return NULL;
85 }
86