xref: /openbmc/linux/arch/x86/include/asm/pgalloc.h (revision b4e18b29)
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 /*
33  * Flags to use when allocating a user page table page.
34  */
35 extern gfp_t __userpte_alloc_gfp;
36 
37 #ifdef CONFIG_PAGE_TABLE_ISOLATION
38 /*
39  * Instead of one PGD, we acquire two PGDs.  Being order-1, it is
40  * both 8k in size and 8k-aligned.  That lets us just flip bit 12
41  * in a pointer to swap between the two 4k halves.
42  */
43 #define PGD_ALLOCATION_ORDER 1
44 #else
45 #define PGD_ALLOCATION_ORDER 0
46 #endif
47 
48 /*
49  * Allocate and free page tables.
50  */
51 extern pgd_t *pgd_alloc(struct mm_struct *);
52 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
53 
54 extern pgtable_t pte_alloc_one(struct mm_struct *);
55 
56 extern void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte);
57 
58 static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
59 				  unsigned long address)
60 {
61 	___pte_free_tlb(tlb, pte);
62 }
63 
64 static inline void pmd_populate_kernel(struct mm_struct *mm,
65 				       pmd_t *pmd, pte_t *pte)
66 {
67 	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
68 	set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
69 }
70 
71 static inline void pmd_populate_kernel_safe(struct mm_struct *mm,
72 				       pmd_t *pmd, pte_t *pte)
73 {
74 	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
75 	set_pmd_safe(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
76 }
77 
78 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
79 				struct page *pte)
80 {
81 	unsigned long pfn = page_to_pfn(pte);
82 
83 	paravirt_alloc_pte(mm, pfn);
84 	set_pmd(pmd, __pmd(((pteval_t)pfn << PAGE_SHIFT) | _PAGE_TABLE));
85 }
86 
87 #define pmd_pgtable(pmd) pmd_page(pmd)
88 
89 #if CONFIG_PGTABLE_LEVELS > 2
90 extern void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd);
91 
92 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
93 				  unsigned long address)
94 {
95 	___pmd_free_tlb(tlb, pmd);
96 }
97 
98 #ifdef CONFIG_X86_PAE
99 extern void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd);
100 #else	/* !CONFIG_X86_PAE */
101 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
102 {
103 	paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
104 	set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
105 }
106 
107 static inline void pud_populate_safe(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
108 {
109 	paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
110 	set_pud_safe(pud, __pud(_PAGE_TABLE | __pa(pmd)));
111 }
112 #endif	/* CONFIG_X86_PAE */
113 
114 #if CONFIG_PGTABLE_LEVELS > 3
115 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
116 {
117 	paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
118 	set_p4d(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
119 }
120 
121 static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
122 {
123 	paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
124 	set_p4d_safe(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
125 }
126 
127 extern void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud);
128 
129 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
130 				  unsigned long address)
131 {
132 	___pud_free_tlb(tlb, pud);
133 }
134 
135 #if CONFIG_PGTABLE_LEVELS > 4
136 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
137 {
138 	if (!pgtable_l5_enabled())
139 		return;
140 	paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
141 	set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
142 }
143 
144 static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
145 {
146 	if (!pgtable_l5_enabled())
147 		return;
148 	paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
149 	set_pgd_safe(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
150 }
151 
152 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
153 {
154 	gfp_t gfp = GFP_KERNEL_ACCOUNT;
155 
156 	if (mm == &init_mm)
157 		gfp &= ~__GFP_ACCOUNT;
158 	return (p4d_t *)get_zeroed_page(gfp);
159 }
160 
161 static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
162 {
163 	if (!pgtable_l5_enabled())
164 		return;
165 
166 	BUG_ON((unsigned long)p4d & (PAGE_SIZE-1));
167 	free_page((unsigned long)p4d);
168 }
169 
170 extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d);
171 
172 static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
173 				  unsigned long address)
174 {
175 	if (pgtable_l5_enabled())
176 		___p4d_free_tlb(tlb, p4d);
177 }
178 
179 #endif	/* CONFIG_PGTABLE_LEVELS > 4 */
180 #endif	/* CONFIG_PGTABLE_LEVELS > 3 */
181 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
182 
183 #endif /* _ASM_X86_PGALLOC_H */
184