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 <linux/pgtable.h>
13#include <asm/page.h>
14
15#define hugetlb_free_pgd_range			free_pgd_range
16#define hugepages_supported()			(MACHINE_HAS_EDAT1)
17
18void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
19		     pte_t *ptep, pte_t pte, unsigned long sz);
20void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
21		     pte_t *ptep, pte_t pte);
22pte_t huge_ptep_get(pte_t *ptep);
23pte_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 */
30static inline int prepare_hugepage_range(struct file *file,
31			unsigned long addr, unsigned long len)
32{
33	struct hstate *h = hstate_file(file);
34
35	if (len & ~huge_page_mask(h))
36		return -EINVAL;
37	if (addr & ~huge_page_mask(h))
38		return -EINVAL;
39	return 0;
40}
41
42static inline void arch_clear_hugepage_flags(struct page *page)
43{
44	clear_bit(PG_arch_1, &page->flags);
45}
46#define arch_clear_hugepage_flags arch_clear_hugepage_flags
47
48static inline void huge_pte_clear(struct mm_struct *mm, unsigned long addr,
49				  pte_t *ptep, unsigned long sz)
50{
51	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
52		set_pte(ptep, __pte(_REGION3_ENTRY_EMPTY));
53	else
54		set_pte(ptep, __pte(_SEGMENT_ENTRY_EMPTY));
55}
56
57static inline pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
58					  unsigned long address, pte_t *ptep)
59{
60	return huge_ptep_get_and_clear(vma->vm_mm, address, ptep);
61}
62
63static inline int huge_ptep_set_access_flags(struct vm_area_struct *vma,
64					     unsigned long addr, pte_t *ptep,
65					     pte_t pte, int dirty)
66{
67	int changed = !pte_same(huge_ptep_get(ptep), pte);
68	if (changed) {
69		huge_ptep_get_and_clear(vma->vm_mm, addr, ptep);
70		__set_huge_pte_at(vma->vm_mm, addr, ptep, pte);
71	}
72	return changed;
73}
74
75static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
76					   unsigned long addr, pte_t *ptep)
77{
78	pte_t pte = huge_ptep_get_and_clear(mm, addr, ptep);
79	__set_huge_pte_at(mm, addr, ptep, pte_wrprotect(pte));
80}
81
82static inline pte_t mk_huge_pte(struct page *page, pgprot_t pgprot)
83{
84	return mk_pte(page, pgprot);
85}
86
87static inline int huge_pte_none(pte_t pte)
88{
89	return pte_none(pte);
90}
91
92static inline int huge_pte_none_mostly(pte_t pte)
93{
94	return huge_pte_none(pte);
95}
96
97static inline int huge_pte_write(pte_t pte)
98{
99	return pte_write(pte);
100}
101
102static inline int huge_pte_dirty(pte_t pte)
103{
104	return pte_dirty(pte);
105}
106
107static inline pte_t huge_pte_mkwrite(pte_t pte)
108{
109	return pte_mkwrite_novma(pte);
110}
111
112static inline pte_t huge_pte_mkdirty(pte_t pte)
113{
114	return pte_mkdirty(pte);
115}
116
117static inline pte_t huge_pte_wrprotect(pte_t pte)
118{
119	return pte_wrprotect(pte);
120}
121
122static inline pte_t huge_pte_modify(pte_t pte, pgprot_t newprot)
123{
124	return pte_modify(pte, newprot);
125}
126
127static inline pte_t huge_pte_mkuffd_wp(pte_t pte)
128{
129	return pte;
130}
131
132static inline pte_t huge_pte_clear_uffd_wp(pte_t pte)
133{
134	return pte;
135}
136
137static inline int huge_pte_uffd_wp(pte_t pte)
138{
139	return 0;
140}
141
142static inline bool gigantic_page_runtime_supported(void)
143{
144	return true;
145}
146
147#endif /* _ASM_S390_HUGETLB_H */
148