xref: /openbmc/linux/arch/sh/mm/hugetlbpage.c (revision fd589a8f)
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,
26 			unsigned long addr, unsigned long sz)
27 {
28 	pgd_t *pgd;
29 	pud_t *pud;
30 	pmd_t *pmd;
31 	pte_t *pte = NULL;
32 
33 	pgd = pgd_offset(mm, addr);
34 	if (pgd) {
35 		pud = pud_alloc(mm, pgd, addr);
36 		if (pud) {
37 			pmd = pmd_alloc(mm, pud, addr);
38 			if (pmd)
39 				pte = pte_alloc_map(mm, pmd, addr);
40 		}
41 	}
42 
43 	return pte;
44 }
45 
46 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
47 {
48 	pgd_t *pgd;
49 	pud_t *pud;
50 	pmd_t *pmd;
51 	pte_t *pte = NULL;
52 
53 	pgd = pgd_offset(mm, addr);
54 	if (pgd) {
55 		pud = pud_offset(pgd, addr);
56 		if (pud) {
57 			pmd = pmd_offset(pud, addr);
58 			if (pmd)
59 				pte = pte_offset_map(pmd, addr);
60 		}
61 	}
62 
63 	return pte;
64 }
65 
66 int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
67 {
68 	return 0;
69 }
70 
71 struct page *follow_huge_addr(struct mm_struct *mm,
72 			      unsigned long address, int write)
73 {
74 	return ERR_PTR(-EINVAL);
75 }
76 
77 int pmd_huge(pmd_t pmd)
78 {
79 	return 0;
80 }
81 
82 int pud_huge(pud_t pud)
83 {
84 	return 0;
85 }
86 
87 struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
88 			     pmd_t *pmd, int write)
89 {
90 	return NULL;
91 }
92