xref: /linux/arch/x86/include/asm/pgalloc.h (revision f694f30e81c4ade358eb8c75273bac1a48f0cb8f)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PGALLOC_H
3 #define _ASM_X86_PGALLOC_H
4 
5 #include <linux/threads.h>
6 #include <linux/mm.h>		/* for struct page */
7 #include <linux/pagemap.h>
8 
9 #define __HAVE_ARCH_PTE_ALLOC_ONE
10 #define __HAVE_ARCH_PGD_FREE
11 #include <asm-generic/pgalloc.h>
12 
13 static inline int  __paravirt_pgd_alloc(struct mm_struct *mm) { return 0; }
14 
15 #ifdef CONFIG_PARAVIRT_XXL
16 #include <asm/paravirt.h>
17 #else
18 #define paravirt_pgd_alloc(mm)	__paravirt_pgd_alloc(mm)
19 static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd) {}
20 static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn)	{}
21 static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn)	{}
22 static inline void paravirt_alloc_pmd_clone(unsigned long pfn, unsigned long clonepfn,
23 					    unsigned long start, unsigned long count) {}
24 static inline void paravirt_alloc_pud(struct mm_struct *mm, unsigned long pfn)	{}
25 static inline void paravirt_alloc_p4d(struct mm_struct *mm, unsigned long pfn)	{}
26 static inline void paravirt_release_pte(unsigned long pfn) {}
27 static inline void paravirt_release_pmd(unsigned long pfn) {}
28 static inline void paravirt_release_pud(unsigned long pfn) {}
29 static inline void paravirt_release_p4d(unsigned long pfn) {}
30 #endif
31 
32 #ifdef CONFIG_MITIGATION_PAGE_TABLE_ISOLATION
33 /*
34  * Instead of one PGD, we acquire two PGDs.  Being order-1, it is
35  * both 8k in size and 8k-aligned.  That lets us just flip bit 12
36  * in a pointer to swap between the two 4k halves.
37  */
38 #define PGD_ALLOCATION_ORDER 1
39 #else
40 #define PGD_ALLOCATION_ORDER 0
41 #endif
42 
43 /*
44  * Allocate and free page tables.
45  */
46 extern pgd_t *pgd_alloc(struct mm_struct *);
47 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
48 
49 extern pgtable_t pte_alloc_one(struct mm_struct *);
50 
51 extern void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte);
52 
53 static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
54 				  unsigned long address)
55 {
56 	___pte_free_tlb(tlb, pte);
57 }
58 
59 static inline void pmd_populate_kernel(struct mm_struct *mm,
60 				       pmd_t *pmd, pte_t *pte)
61 {
62 	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
63 	set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
64 }
65 
66 static inline void pmd_populate_kernel_safe(struct mm_struct *mm,
67 				       pmd_t *pmd, pte_t *pte)
68 {
69 	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
70 	set_pmd_safe(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
71 }
72 
73 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
74 				struct page *pte)
75 {
76 	unsigned long pfn = page_to_pfn(pte);
77 
78 	paravirt_alloc_pte(mm, pfn);
79 	set_pmd(pmd, __pmd(((pteval_t)pfn << PAGE_SHIFT) | _PAGE_TABLE));
80 }
81 
82 #if CONFIG_PGTABLE_LEVELS > 2
83 extern void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd);
84 
85 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
86 				  unsigned long address)
87 {
88 	___pmd_free_tlb(tlb, pmd);
89 }
90 
91 #ifdef CONFIG_X86_PAE
92 extern void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd);
93 #else	/* !CONFIG_X86_PAE */
94 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
95 {
96 	paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
97 	set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
98 }
99 
100 static inline void pud_populate_safe(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
101 {
102 	paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
103 	set_pud_safe(pud, __pud(_PAGE_TABLE | __pa(pmd)));
104 }
105 #endif	/* CONFIG_X86_PAE */
106 
107 #if CONFIG_PGTABLE_LEVELS > 3
108 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
109 {
110 	paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
111 	set_p4d(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
112 }
113 
114 static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
115 {
116 	paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
117 	set_p4d_safe(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
118 }
119 
120 extern void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud);
121 
122 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
123 				  unsigned long address)
124 {
125 	___pud_free_tlb(tlb, pud);
126 }
127 
128 #if CONFIG_PGTABLE_LEVELS > 4
129 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
130 {
131 	if (!pgtable_l5_enabled())
132 		return;
133 	paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
134 	set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
135 }
136 
137 static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
138 {
139 	if (!pgtable_l5_enabled())
140 		return;
141 	paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
142 	set_pgd_safe(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
143 }
144 
145 extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d);
146 
147 static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
148 				  unsigned long address)
149 {
150 	if (pgtable_l5_enabled())
151 		___p4d_free_tlb(tlb, p4d);
152 }
153 
154 #endif	/* CONFIG_PGTABLE_LEVELS > 4 */
155 #endif	/* CONFIG_PGTABLE_LEVELS > 3 */
156 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
157 
158 #endif /* _ASM_X86_PGALLOC_H */
159