1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2009 Chen Liqin <[email protected]>
4 * Copyright (C) 2012 Regents of the University of California
5 */
6
7 #ifndef _ASM_RISCV_PGALLOC_H
8 #define _ASM_RISCV_PGALLOC_H
9
10 #include <linux/mm.h>
11 #include <asm/sbi.h>
12 #include <asm/tlb.h>
13
14 #ifdef CONFIG_MMU
15 #define __HAVE_ARCH_PUD_FREE
16 #include <asm-generic/pgalloc.h>
17
18 /*
19 * While riscv platforms with riscv_ipi_for_rfence as true require an IPI to
20 * perform TLB shootdown, some platforms with riscv_ipi_for_rfence as false use
21 * SBI to perform TLB shootdown. To keep software pagetable walkers safe in this
22 * case we switch to RCU based table free (MMU_GATHER_RCU_TABLE_FREE). See the
23 * comment below 'ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE' in include/asm-generic/tlb.h
24 * for more details.
25 */
riscv_tlb_remove_ptdesc(struct mmu_gather * tlb,void * pt)26 static inline void riscv_tlb_remove_ptdesc(struct mmu_gather *tlb, void *pt)
27 {
28 if (riscv_use_sbi_for_rfence()) {
29 tlb_remove_ptdesc(tlb, pt);
30 } else {
31 pagetable_dtor(pt);
32 tlb_remove_page_ptdesc(tlb, pt);
33 }
34 }
35
pmd_populate_kernel(struct mm_struct * mm,pmd_t * pmd,pte_t * pte)36 static inline void pmd_populate_kernel(struct mm_struct *mm,
37 pmd_t *pmd, pte_t *pte)
38 {
39 unsigned long pfn = virt_to_pfn(pte);
40
41 set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
42 }
43
pmd_populate(struct mm_struct * mm,pmd_t * pmd,pgtable_t pte)44 static inline void pmd_populate(struct mm_struct *mm,
45 pmd_t *pmd, pgtable_t pte)
46 {
47 unsigned long pfn = virt_to_pfn(page_address(pte));
48
49 set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
50 }
51
52 #ifndef __PAGETABLE_PMD_FOLDED
pud_populate(struct mm_struct * mm,pud_t * pud,pmd_t * pmd)53 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
54 {
55 unsigned long pfn = virt_to_pfn(pmd);
56
57 set_pud(pud, __pud((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
58 }
59
p4d_populate(struct mm_struct * mm,p4d_t * p4d,pud_t * pud)60 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
61 {
62 if (pgtable_l4_enabled) {
63 unsigned long pfn = virt_to_pfn(pud);
64
65 set_p4d(p4d, __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
66 }
67 }
68
p4d_populate_safe(struct mm_struct * mm,p4d_t * p4d,pud_t * pud)69 static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d,
70 pud_t *pud)
71 {
72 if (pgtable_l4_enabled) {
73 unsigned long pfn = virt_to_pfn(pud);
74
75 set_p4d_safe(p4d,
76 __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
77 }
78 }
79
pgd_populate(struct mm_struct * mm,pgd_t * pgd,p4d_t * p4d)80 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
81 {
82 if (pgtable_l5_enabled) {
83 unsigned long pfn = virt_to_pfn(p4d);
84
85 set_pgd(pgd, __pgd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
86 }
87 }
88
pgd_populate_safe(struct mm_struct * mm,pgd_t * pgd,p4d_t * p4d)89 static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd,
90 p4d_t *p4d)
91 {
92 if (pgtable_l5_enabled) {
93 unsigned long pfn = virt_to_pfn(p4d);
94
95 set_pgd_safe(pgd,
96 __pgd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
97 }
98 }
99
100 #define pud_free pud_free
pud_free(struct mm_struct * mm,pud_t * pud)101 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
102 {
103 if (pgtable_l4_enabled)
104 __pud_free(mm, pud);
105 }
106
__pud_free_tlb(struct mmu_gather * tlb,pud_t * pud,unsigned long addr)107 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
108 unsigned long addr)
109 {
110 if (pgtable_l4_enabled)
111 riscv_tlb_remove_ptdesc(tlb, virt_to_ptdesc(pud));
112 }
113
__p4d_free_tlb(struct mmu_gather * tlb,p4d_t * p4d,unsigned long addr)114 static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
115 unsigned long addr)
116 {
117 if (pgtable_l5_enabled)
118 riscv_tlb_remove_ptdesc(tlb, virt_to_ptdesc(p4d));
119 }
120 #endif /* __PAGETABLE_PMD_FOLDED */
121
sync_kernel_mappings(pgd_t * pgd)122 static inline void sync_kernel_mappings(pgd_t *pgd)
123 {
124 memcpy(pgd + USER_PTRS_PER_PGD,
125 init_mm.pgd + USER_PTRS_PER_PGD,
126 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
127 }
128
pgd_alloc(struct mm_struct * mm)129 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
130 {
131 pgd_t *pgd;
132
133 pgd = __pgd_alloc(mm, 0);
134 if (likely(pgd != NULL)) {
135 /* Copy kernel mappings */
136 sync_kernel_mappings(pgd);
137 }
138 return pgd;
139 }
140
141 #ifndef __PAGETABLE_PMD_FOLDED
142
__pmd_free_tlb(struct mmu_gather * tlb,pmd_t * pmd,unsigned long addr)143 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
144 unsigned long addr)
145 {
146 riscv_tlb_remove_ptdesc(tlb, virt_to_ptdesc(pmd));
147 }
148
149 #endif /* __PAGETABLE_PMD_FOLDED */
150
__pte_free_tlb(struct mmu_gather * tlb,pgtable_t pte,unsigned long addr)151 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
152 unsigned long addr)
153 {
154 riscv_tlb_remove_ptdesc(tlb, page_ptdesc(pte));
155 }
156 #endif /* CONFIG_MMU */
157
158 #endif /* _ASM_RISCV_PGALLOC_H */
159