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
9static inline int __paravirt_pgd_alloc(struct mm_struct *mm) { return 0; }
10
11#ifdef CONFIG_PARAVIRT_XXL
12#include <asm/paravirt.h>
13#else
14#define paravirt_pgd_alloc(mm) __paravirt_pgd_alloc(mm)
15static inline void paravirt_pgd_free(struct mm_struct *mm, pgd_t *pgd) {}
16static inline void paravirt_alloc_pte(struct mm_struct *mm, unsigned long pfn) {}
17static inline void paravirt_alloc_pmd(struct mm_struct *mm, unsigned long pfn) {}
18static inline void paravirt_alloc_pmd_clone(unsigned long pfn, unsigned long clonepfn,
19 unsigned long start, unsigned long count) {}
20static inline void paravirt_alloc_pud(struct mm_struct *mm, unsigned long pfn) {}
21static inline void paravirt_alloc_p4d(struct mm_struct *mm, unsigned long pfn) {}
22static inline void paravirt_release_pte(unsigned long pfn) {}
23static inline void paravirt_release_pmd(unsigned long pfn) {}
24static inline void paravirt_release_pud(unsigned long pfn) {}
25static inline void paravirt_release_p4d(unsigned long pfn) {}
26#endif
27
28/*
29 * Flags to use when allocating a user page table page.
30 */
31extern gfp_t __userpte_alloc_gfp;
32
33#ifdef CONFIG_PAGE_TABLE_ISOLATION
34/*
35 * Instead of one PGD, we acquire two PGDs. Being order-1, it is
36 * both 8k in size and 8k-aligned. That lets us just flip bit 12
37 * in a pointer to swap between the two 4k halves.
38 */
39#define PGD_ALLOCATION_ORDER 1
40#else
41#define PGD_ALLOCATION_ORDER 0
42#endif
43
44/*
45 * Allocate and free page tables.
46 */
47extern pgd_t *pgd_alloc(struct mm_struct *);
48extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
49
50extern pte_t *pte_alloc_one_kernel(struct mm_struct *);
51extern pgtable_t pte_alloc_one(struct mm_struct *);
52
53/* Should really implement gc for free page table pages. This could be
54 done with a reference count in struct page. */
55
56static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
57{
58 BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
59 free_page((unsigned long)pte);
60}
61
62static inline void pte_free(struct mm_struct *mm, struct page *pte)
63{
64 pgtable_page_dtor(pte);
65 __free_page(pte);
66}
67
68extern void ___pte_free_tlb(struct mmu_gather *tlb, struct page *pte);
69
70static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
71 unsigned long address)
72{
73 ___pte_free_tlb(tlb, pte);
74}
75
76static inline void pmd_populate_kernel(struct mm_struct *mm,
77 pmd_t *pmd, pte_t *pte)
78{
79 paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
80 set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
81}
82
83static inline void pmd_populate_kernel_safe(struct mm_struct *mm,
84 pmd_t *pmd, pte_t *pte)
85{
86 paravirt_alloc_pte(mm, __pa(pte) >> PAGE_SHIFT);
87 set_pmd_safe(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
88}
89
90static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
91 struct page *pte)
92{
93 unsigned long pfn = page_to_pfn(pte);
94
95 paravirt_alloc_pte(mm, pfn);
96 set_pmd(pmd, __pmd(((pteval_t)pfn << PAGE_SHIFT) | _PAGE_TABLE));
97}
98
99#define pmd_pgtable(pmd) pmd_page(pmd)
100
101#if CONFIG_PGTABLE_LEVELS > 2
102static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
103{
104 struct page *page;
105 gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO;
106
107 if (mm == &init_mm)
108 gfp &= ~__GFP_ACCOUNT;
109 page = alloc_pages(gfp, 0);
110 if (!page)
111 return NULL;
112 if (!pgtable_pmd_page_ctor(page)) {
113 __free_pages(page, 0);
114 return NULL;
115 }
116 return (pmd_t *)page_address(page);
117}
118
119static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
120{
121 BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
122 pgtable_pmd_page_dtor(virt_to_page(pmd));
123 free_page((unsigned long)pmd);
124}
125
126extern void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd);
127
128static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
129 unsigned long address)
130{
131 ___pmd_free_tlb(tlb, pmd);
132}
133
134#ifdef CONFIG_X86_PAE
135extern void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd);
136#else /* !CONFIG_X86_PAE */
137static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
138{
139 paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
140 set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
141}
142
143static inline void pud_populate_safe(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
144{
145 paravirt_alloc_pmd(mm, __pa(pmd) >> PAGE_SHIFT);
146 set_pud_safe(pud, __pud(_PAGE_TABLE | __pa(pmd)));
147}
148#endif /* CONFIG_X86_PAE */
149
150#if CONFIG_PGTABLE_LEVELS > 3
151static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
152{
153 paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
154 set_p4d(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
155}
156
157static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
158{
159 paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
160 set_p4d_safe(p4d, __p4d(_PAGE_TABLE | __pa(pud)));
161}
162
163static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
164{
165 gfp_t gfp = GFP_KERNEL_ACCOUNT;
166
167 if (mm == &init_mm)
168 gfp &= ~__GFP_ACCOUNT;
169 return (pud_t *)get_zeroed_page(gfp);
170}
171
172static inline void pud_free(struct mm_struct *mm, pud_t *pud)
173{
174 BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
175 free_page((unsigned long)pud);
176}
177
178extern void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud);
179
180static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
181 unsigned long address)
182{
183 ___pud_free_tlb(tlb, pud);
184}
185
186#if CONFIG_PGTABLE_LEVELS > 4
187static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
188{
189 if (!pgtable_l5_enabled())
190 return;
191 paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
192 set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
193}
194
195static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
196{
197 if (!pgtable_l5_enabled())
198 return;
199 paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
200 set_pgd_safe(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
201}
202
203static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long addr)
204{
205 gfp_t gfp = GFP_KERNEL_ACCOUNT;
206
207 if (mm == &init_mm)
208 gfp &= ~__GFP_ACCOUNT;
209 return (p4d_t *)get_zeroed_page(gfp);
210}
211
212static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
213{
214 if (!pgtable_l5_enabled())
215 return;
216
217 BUG_ON((unsigned long)p4d & (PAGE_SIZE-1));
218 free_page((unsigned long)p4d);
219}
220
221extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d);
222
223static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
224 unsigned long address)
225{
226 if (pgtable_l5_enabled())
227 ___p4d_free_tlb(tlb, p4d);
228}
229
230#endif /* CONFIG_PGTABLE_LEVELS > 4 */
231#endif /* CONFIG_PGTABLE_LEVELS > 3 */
232#endif /* CONFIG_PGTABLE_LEVELS > 2 */
233
234#endif /* _ASM_X86_PGALLOC_H */
235