1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2020 Loongson Technology Corporation Limited
4 */
5
6 #include <linux/fs.h>
7 #include <linux/mm.h>
8 #include <linux/hugetlb.h>
9 #include <linux/pagemap.h>
10 #include <linux/err.h>
11 #include <linux/sysctl.h>
12 #include <asm/mman.h>
13 #include <asm/tlb.h>
14 #include <asm/tlbflush.h>
15
huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz)16 pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr,
17 unsigned long sz)
18 {
19 pgd_t *pgd;
20 p4d_t *p4d;
21 pud_t *pud;
22 pte_t *pte = NULL;
23
24 pgd = pgd_offset(mm, addr);
25 p4d = p4d_alloc(mm, pgd, addr);
26 pud = pud_alloc(mm, p4d, addr);
27 if (pud)
28 pte = (pte_t *)pmd_alloc(mm, pud, addr);
29
30 return pte;
31 }
32
huge_pte_offset(struct mm_struct *mm, unsigned long addr, unsigned long sz)33 pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
34 unsigned long sz)
35 {
36 pgd_t *pgd;
37 p4d_t *p4d;
38 pud_t *pud;
39 pmd_t *pmd = NULL;
40
41 pgd = pgd_offset(mm, addr);
42 if (pgd_present(*pgd)) {
43 p4d = p4d_offset(pgd, addr);
44 if (p4d_present(*p4d)) {
45 pud = pud_offset(p4d, addr);
46 if (pud_present(*pud))
47 pmd = pmd_offset(pud, addr);
48 }
49 }
50 return (pte_t *) pmd;
51 }
52
pmd_huge(pmd_t pmd)53 int pmd_huge(pmd_t pmd)
54 {
55 return (pmd_val(pmd) & _PAGE_HUGE) != 0;
56 }
57 EXPORT_SYMBOL(pmd_huge);
58
pud_huge(pud_t pud)59 int pud_huge(pud_t pud)
60 {
61 return (pud_val(pud) & _PAGE_HUGE) != 0;
62 }
63 EXPORT_SYMBOL(pud_huge);
64
pmd_to_entrylo(unsigned long pmd_val)65 uint64_t pmd_to_entrylo(unsigned long pmd_val)
66 {
67 uint64_t val;
68 /* PMD as PTE. Must be huge page */
69 if (!pmd_huge(__pmd(pmd_val)))
70 panic("%s", __func__);
71
72 val = pmd_val ^ _PAGE_HUGE;
73 val |= ((val & _PAGE_HGLOBAL) >>
74 (_PAGE_HGLOBAL_SHIFT - _PAGE_GLOBAL_SHIFT));
75
76 return val;
77 }
78