xref: /openbmc/linux/arch/s390/include/asm/hugetlb.h (revision 9cfc5c90) 
1 /*
2  *  IBM System z Huge TLB Page Support for Kernel.
3  *
4  *    Copyright IBM Corp. 2008
5  *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
6  */
7 
8 #ifndef _ASM_S390_HUGETLB_H
9 #define _ASM_S390_HUGETLB_H
10 
11 #include <asm/page.h>
12 #include <asm/pgtable.h>
13 
14 
15 #define is_hugepage_only_range(mm, addr, len)	0
16 #define hugetlb_free_pgd_range			free_pgd_range
17 #define hugepages_supported()			(MACHINE_HAS_HPAGE)
18 
19 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
20 		     pte_t *ptep, pte_t pte);
21 pte_t huge_ptep_get(pte_t *ptep);
22 pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
23 			      unsigned long addr, pte_t *ptep);
24 
25 /*
26  * If the arch doesn't supply something else, assume that hugepage
27  * size aligned regions are ok without further preparation.
28  */
29 static inline int prepare_hugepage_range(struct file *file,
30 			unsigned long addr, unsigned long len)
31 {
32 	if (len & ~HPAGE_MASK)
33 		return -EINVAL;
34 	if (addr & ~HPAGE_MASK)
35 		return -EINVAL;
36 	return 0;
37 }
38 
39 #define arch_clear_hugepage_flags(page)		do { } while (0)
40 
41 static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
42 				  pte_t *ptep)
43 {
44 	pte_val(*ptep) = _SEGMENT_ENTRY_EMPTY;
45 }
46 
47 static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
48 					 unsigned long address, pte_t *ptep)
49 {
50 	huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
51 }
52 
53 static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
54 					     unsigned long addr, pte_t *ptep,
55 					     pte_t pte, int dirty)
56 {
57 	int changed = !pte_same(huge_ptep_get(ptep), pte);
58 	if (changed) {
59 		huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
60 		set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
61 	}
62 	return changed;
63 }
64 
65 static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
66 					   unsigned long addr, pte_t *ptep)
67 {
68 	pte_t pte = huge_ptep_get_and_clear(mm, addr, ptep);
69 	set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte));
70 }
71 
72 static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
73 {
74 	return mk_pte(page, pgprot);
75 }
76 
77 static inline int huge_pte_none(pte_t pte)
78 {
79 	return pte_none(pte);
80 }
81 
82 static inline int huge_pte_write(pte_t pte)
83 {
84 	return pte_write(pte);
85 }
86 
87 static inline int huge_pte_dirty(pte_t pte)
88 {
89 	return pte_dirty(pte);
90 }
91 
92 static inline pte_t huge_pte_mkwrite(pte_t pte)
93 {
94 	return pte_mkwrite(pte);
95 }
96 
97 static inline pte_t huge_pte_mkdirty(pte_t pte)
98 {
99 	return pte_mkdirty(pte);
100 }
101 
102 static inline pte_t huge_pte_wrprotect(pte_t pte)
103 {
104 	return pte_wrprotect(pte);
105 }
106 
107 static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
108 {
109 	return pte_modify(pte, newprot);
110 }
111 
112 #endif /* _ASM_S390_HUGETLB_H */
113