xref: /openbmc/linux/arch/s390/include/asm/hugetlb.h (revision 68198dca) 
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  IBM System z Huge TLB Page Support for Kernel.
4  *
5  *    Copyright IBM Corp. 2008
6  *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
7  */
8 
9 #ifndef _ASM_S390_HUGETLB_H
10 #define _ASM_S390_HUGETLB_H
11 
12 #include <asm/page.h>
13 #include <asm/pgtable.h>
14 
15 
16 #define is_hugepage_only_range(mm, addr, len)	0
17 #define hugetlb_free_pgd_range			free_pgd_range
18 #define hugepages_supported()			(MACHINE_HAS_EDAT1)
19 
20 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
21 		     pte_t *ptep, pte_t pte);
22 pte_t huge_ptep_get(pte_t *ptep);
23 pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
24 			      unsigned long addr, pte_t *ptep);
25 
26 /*
27  * If the arch doesn't supply something else, assume that hugepage
28  * size aligned regions are ok without further preparation.
29  */
30 static inline int prepare_hugepage_range(struct file *file,
31 			unsigned long addr, unsigned long len)
32 {
33 	if (len & ~HPAGE_MASK)
34 		return -EINVAL;
35 	if (addr & ~HPAGE_MASK)
36 		return -EINVAL;
37 	return 0;
38 }
39 
40 #define arch_clear_hugepage_flags(page)		do { } while (0)
41 
42 static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
43 				  pte_t *ptep, unsigned long sz)
44 {
45 	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
46 		pte_val(*ptep) = _REGION3_ENTRY_EMPTY;
47 	else
48 		pte_val(*ptep) = _SEGMENT_ENTRY_EMPTY;
49 }
50 
51 static inline void huge_ptep_clear_flush(struct vm_area_struct *vma,
52 					 unsigned long address, pte_t *ptep)
53 {
54 	huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
55 }
56 
57 static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
58 					     unsigned long addr, pte_t *ptep,
59 					     pte_t pte, int dirty)
60 {
61 	int changed = !pte_same(huge_ptep_get(ptep), pte);
62 	if (changed) {
63 		huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
64 		set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
65 	}
66 	return changed;
67 }
68 
69 static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
70 					   unsigned long addr, pte_t *ptep)
71 {
72 	pte_t pte = huge_ptep_get_and_clear(mm, addr, ptep);
73 	set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte));
74 }
75 
76 static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
77 {
78 	return mk_pte(page, pgprot);
79 }
80 
81 static inline int huge_pte_none(pte_t pte)
82 {
83 	return pte_none(pte);
84 }
85 
86 static inline int huge_pte_write(pte_t pte)
87 {
88 	return pte_write(pte);
89 }
90 
91 static inline int huge_pte_dirty(pte_t pte)
92 {
93 	return pte_dirty(pte);
94 }
95 
96 static inline pte_t huge_pte_mkwrite(pte_t pte)
97 {
98 	return pte_mkwrite(pte);
99 }
100 
101 static inline pte_t huge_pte_mkdirty(pte_t pte)
102 {
103 	return pte_mkdirty(pte);
104 }
105 
106 static inline pte_t huge_pte_wrprotect(pte_t pte)
107 {
108 	return pte_wrprotect(pte);
109 }
110 
111 static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
112 {
113 	return pte_modify(pte, newprot);
114 }
115 
116 #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE
117 static inline bool gigantic_page_supported(void) { return true; }
118 #endif
119 #endif /* _ASM_S390_HUGETLB_H */
120