1// SPDX-License-Identifier: GPL-2.0
2
3#include <asm/pgalloc.h>
4#include <linux/gfp.h>
5#include <linux/kernel.h>
6#include <linux/pgtable.h>
7
8int ptep_set_access_flags(struct vm_area_struct *vma,
9 unsigned long address, pte_t *ptep,
10 pte_t entry, int dirty)
11{
12 if (!pte_same(a: ptep_get(ptep), b: entry))
13 __set_pte_at(vma->vm_mm, ptep, entry);
14 /*
15 * update_mmu_cache will unconditionally execute, handling both
16 * the case that the PTE changed and the spurious fault case.
17 */
18 return true;
19}
20
21int ptep_test_and_clear_young(struct vm_area_struct *vma,
22 unsigned long address,
23 pte_t *ptep)
24{
25 if (!pte_young(pte: ptep_get(ptep)))
26 return 0;
27 return test_and_clear_bit(nr: _PAGE_ACCESSED_OFFSET, &pte_val(pte: *ptep)addr: );
28}
29EXPORT_SYMBOL_GPL(ptep_test_and_clear_young);
30
31#ifdef CONFIG_64BIT
32pud_t *pud_offset(p4d_t *p4d, unsigned long address)
33{
34 if (pgtable_l4_enabled)
35 return p4d_pgtable(p4d: p4dp_get(p4dp: p4d)) + pud_index(address);
36
37 return (pud_t *)p4d;
38}
39
40p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
41{
42 if (pgtable_l5_enabled)
43 return pgd_pgtable(pgdp_get(pgdp: pgd)) + p4d_index(address);
44
45 return (p4d_t *)pgd;
46}
47#endif
48
49#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
50int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
51{
52 return 0;
53}
54
55void p4d_clear_huge(p4d_t *p4d)
56{
57}
58
59int pud_set_huge(pud_t *pud, phys_addr_t phys, pgprot_t prot)
60{
61 pud_t new_pud = pfn_pud(__phys_to_pfn(phys), pgprot: prot);
62
63 set_pud(pudp: pud, pud: new_pud);
64 return 1;
65}
66
67int pud_clear_huge(pud_t *pud)
68{
69 if (!pud_leaf(pud: pudp_get(pudp: pud)))
70 return 0;
71 pud_clear(pudp: pud);
72 return 1;
73}
74
75int pud_free_pmd_page(pud_t *pud, unsigned long addr)
76{
77 pmd_t *pmd = pud_pgtable(pud: pudp_get(pudp: pud));
78 int i;
79
80 pud_clear(pudp: pud);
81
82 flush_tlb_kernel_range(start: addr, end: addr + PUD_SIZE);
83
84 for (i = 0; i < PTRS_PER_PMD; i++) {
85 if (!pmd_none(pmd: pmd[i])) {
86 pte_t *pte = (pte_t *)pmd_page_vaddr(pmd: pmd[i]);
87
88 pte_free_kernel(NULL, pte);
89 }
90 }
91
92 pmd_free(NULL, pmd);
93
94 return 1;
95}
96
97int pmd_set_huge(pmd_t *pmd, phys_addr_t phys, pgprot_t prot)
98{
99 pmd_t new_pmd = pfn_pmd(__phys_to_pfn(phys), pgprot: prot);
100
101 set_pmd(pmdp: pmd, pmd: new_pmd);
102 return 1;
103}
104
105int pmd_clear_huge(pmd_t *pmd)
106{
107 if (!pmd_leaf(pte: pmdp_get(pmdp: pmd)))
108 return 0;
109 pmd_clear(pmdp: pmd);
110 return 1;
111}
112
113int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
114{
115 pte_t *pte = (pte_t *)pmd_page_vaddr(pmd: pmdp_get(pmdp: pmd));
116
117 pmd_clear(pmdp: pmd);
118
119 flush_tlb_kernel_range(start: addr, end: addr + PMD_SIZE);
120 pte_free_kernel(NULL, pte);
121 return 1;
122}
123
124#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
125#ifdef CONFIG_TRANSPARENT_HUGEPAGE
126pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
127 unsigned long address, pmd_t *pmdp)
128{
129 pmd_t pmd = pmdp_huge_get_and_clear(mm: vma->vm_mm, addr: address, pmdp);
130
131 VM_BUG_ON(address & ~HPAGE_PMD_MASK);
132 VM_BUG_ON(pmd_trans_huge(pmdp_get(pmdp)));
133 /*
134 * When leaf PTE entries (regular pages) are collapsed into a leaf
135 * PMD entry (huge page), a valid non-leaf PTE is converted into a
136 * valid leaf PTE at the level 1 page table. Since the sfence.vma
137 * forms that specify an address only apply to leaf PTEs, we need a
138 * global flush here. collapse_huge_page() assumes these flushes are
139 * eager, so just do the fence here.
140 */
141 flush_tlb_mm(vma->vm_mm);
142 return pmd;
143}
144#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
145

source code of linux/arch/riscv/mm/pgtable.c