xref: /linux/arch/x86/include/asm/pgalloc.h (revision 132db93572821ec2fdf81e354cc40f558faf7e4f)
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 #include <asm-generic/pgalloc.h>	/* for pte_{alloc,free}_one */
11 
12 static inline int  __paravirt_pgd_alloc(struct mm_struct *mm) { return 0; }
13 
14 #ifdef CONFIG_PARAVIRT_XXL
15 #include <asm/paravirt.h>
16 #else
17 #define paravirt_pgd_alloc(mm)	__paravirt_pgd_alloc(mm)
18 static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd) {}
19 static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn)	{}
20 static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn)	{}
21 static inline void paravirt_alloc_pmd_clone(unsigned long pfn, unsigned long clonepfn,
22 					    unsigned long start, unsigned long count) {}
23 static inline void paravirt_alloc_pud(struct mm_struct *mm, unsigned long pfn)	{}
24 static inline void paravirt_alloc_p4d(struct mm_struct *mm, unsigned long pfn)	{}
25 static inline void paravirt_release_pte(unsigned long pfn) {}
26 static inline void paravirt_release_pmd(unsigned long pfn) {}
27 static inline void paravirt_release_pud(unsigned long pfn) {}
28 static inline void paravirt_release_p4d(unsigned long pfn) {}
29 #endif
30 
31 /*
32  * Flags to use when allocating a user page table page.
33  */
34 extern gfp_t __userpte_alloc_gfp;
35 
36 #ifdef CONFIG_PAGE_TABLE_ISOLATION
37 /*
38  * Instead of one PGD, we acquire two PGDs.  Being order-1, it is
39  * both 8k in size and 8k-aligned.  That lets us just flip bit 12
40  * in a pointer to swap between the two 4k halves.
41  */
42 #define PGD_ALLOCATION_ORDER 1
43 #else
44 #define PGD_ALLOCATION_ORDER 0
45 #endif
46 
47 /*
48  * Allocate and free page tables.
49  */
50 extern pgd_t *pgd_alloc(struct mm_struct *);
51 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
52 
53 extern pgtable_t pte_alloc_one(struct mm_struct *);
54 
55 extern void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte);
56 
57 static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
58 				  unsigned long address)
59 {
60 	___pte_free_tlb(tlb, pte);
61 }
62 
63 static inline void pmd_populate_kernel(struct mm_struct *mm,
64 				       pmd_t *pmd, pte_t *pte)
65 {
66 	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
67 	set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
68 }
69 
70 static inline void pmd_populate_kernel_safe(struct mm_struct *mm,
71 				       pmd_t *pmd, pte_t *pte)
72 {
73 	paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
74 	set_pmd_safe(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
75 }
76 
77 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
78 				struct page *pte)
79 {
80 	unsigned long pfn = page_to_pfn(pte);
81 
82 	paravirt_alloc_pte(mm, pfn);
83 	set_pmd(pmd, __pmd(((pteval_t)pfn << PAGE_SHIFT) | _PAGE_TABLE));
84 }
85 
86 #define pmd_pgtable(pmd) pmd_page(pmd)
87 
88 #if CONFIG_PGTABLE_LEVELS > 2
89 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
90 {
91 	struct page *page;
92 	gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO;
93 
94 	if (mm == &init_mm)
95 		gfp &= ~__GFP_ACCOUNT;
96 	page = alloc_pages(gfp, 0);
97 	if (!page)
98 		return NULL;
99 	if (!pgtable_pmd_page_ctor(page)) {
100 		__free_pages(page, 0);
101 		return NULL;
102 	}
103 	return (pmd_t *)page_address(page);
104 }
105 
106 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
107 {
108 	BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
109 	pgtable_pmd_page_dtor(virt_to_page(pmd));
110 	free_page((unsigned long)pmd);
111 }
112 
113 extern void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd);
114 
115 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
116 				  unsigned long address)
117 {
118 	___pmd_free_tlb(tlb, pmd);
119 }
120 
121 #ifdef CONFIG_X86_PAE
122 extern void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd);
123 #else	/* !CONFIG_X86_PAE */
124 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
125 {
126 	paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
127 	set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
128 }
129 
130 static inline void pud_populate_safe(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
131 {
132 	paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
133 	set_pud_safe(pud, __pud(_PAGE_TABLE | __pa(pmd)));
134 }
135 #endif	/* CONFIG_X86_PAE */
136 
137 #if CONFIG_PGTABLE_LEVELS > 3
138 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
139 {
140 	paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
141 	set_p4d(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
142 }
143 
144 static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
145 {
146 	paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
147 	set_p4d_safe(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
148 }
149 
150 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
151 {
152 	gfp_t gfp = GFP_KERNEL_ACCOUNT;
153 
154 	if (mm == &init_mm)
155 		gfp &= ~__GFP_ACCOUNT;
156 	return (pud_t *)get_zeroed_page(gfp);
157 }
158 
159 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
160 {
161 	BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
162 	free_page((unsigned long)pud);
163 }
164 
165 extern void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud);
166 
167 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
168 				  unsigned long address)
169 {
170 	___pud_free_tlb(tlb, pud);
171 }
172 
173 #if CONFIG_PGTABLE_LEVELS > 4
174 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
175 {
176 	if (!pgtable_l5_enabled())
177 		return;
178 	paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
179 	set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
180 }
181 
182 static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
183 {
184 	if (!pgtable_l5_enabled())
185 		return;
186 	paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
187 	set_pgd_safe(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
188 }
189 
190 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
191 {
192 	gfp_t gfp = GFP_KERNEL_ACCOUNT;
193 
194 	if (mm == &init_mm)
195 		gfp &= ~__GFP_ACCOUNT;
196 	return (p4d_t *)get_zeroed_page(gfp);
197 }
198 
199 static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
200 {
201 	if (!pgtable_l5_enabled())
202 		return;
203 
204 	BUG_ON((unsigned long)p4d & (PAGE_SIZE-1));
205 	free_page((unsigned long)p4d);
206 }
207 
208 extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d);
209 
210 static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
211 				  unsigned long address)
212 {
213 	if (pgtable_l5_enabled())
214 		___p4d_free_tlb(tlb, p4d);
215 }
216 
217 #endif	/* CONFIG_PGTABLE_LEVELS > 4 */
218 #endif	/* CONFIG_PGTABLE_LEVELS > 3 */
219 #endif	/* CONFIG_PGTABLE_LEVELS > 2 */
220 
221 #endif /* _ASM_X86_PGALLOC_H */
222