1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_GENERIC_PGALLOC_H
3#define __ASM_GENERIC_PGALLOC_H
4
5#ifdef CONFIG_MMU
6
7#define GFP_PGTABLE_KERNEL (GFP_KERNEL | __GFP_ZERO)
8#define GFP_PGTABLE_USER (GFP_PGTABLE_KERNEL | __GFP_ACCOUNT)
9
10/**
11 * __pte_alloc_one_kernel - allocate memory for a PTE-level kernel page table
12 * @mm: the mm_struct of the current context
13 *
14 * This function is intended for architectures that need
15 * anything beyond simple page allocation.
16 *
17 * Return: pointer to the allocated memory or %NULL on error
18 */
19static inline pte_t *__pte_alloc_one_kernel_noprof(struct mm_struct *mm)
20{
21 struct ptdesc *ptdesc = pagetable_alloc_noprof(GFP_PGTABLE_KERNEL &
22 ~__GFP_HIGHMEM, order: 0);
23
24 if (!ptdesc)
25 return NULL;
26 if (!pagetable_pte_ctor(mm, ptdesc)) {
27 pagetable_free(pt: ptdesc);
28 return NULL;
29 }
30
31 return ptdesc_address(pt: ptdesc);
32}
33#define __pte_alloc_one_kernel(...) alloc_hooks(__pte_alloc_one_kernel_noprof(__VA_ARGS__))
34
35#ifndef __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
36/**
37 * pte_alloc_one_kernel - allocate memory for a PTE-level kernel page table
38 * @mm: the mm_struct of the current context
39 *
40 * Return: pointer to the allocated memory or %NULL on error
41 */
42static inline pte_t *pte_alloc_one_kernel_noprof(struct mm_struct *mm)
43{
44 return __pte_alloc_one_kernel_noprof(mm);
45}
46#define pte_alloc_one_kernel(...) alloc_hooks(pte_alloc_one_kernel_noprof(__VA_ARGS__))
47#endif
48
49/**
50 * pte_free_kernel - free PTE-level kernel page table memory
51 * @mm: the mm_struct of the current context
52 * @pte: pointer to the memory containing the page table
53 */
54static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
55{
56 pagetable_dtor_free(ptdesc: virt_to_ptdesc(x: pte));
57}
58
59/**
60 * __pte_alloc_one - allocate memory for a PTE-level user page table
61 * @mm: the mm_struct of the current context
62 * @gfp: GFP flags to use for the allocation
63 *
64 * Allocate memory for a page table and ptdesc and runs pagetable_pte_ctor().
65 *
66 * This function is intended for architectures that need
67 * anything beyond simple page allocation or must have custom GFP flags.
68 *
69 * Return: `struct page` referencing the ptdesc or %NULL on error
70 */
71static inline pgtable_t __pte_alloc_one_noprof(struct mm_struct *mm, gfp_t gfp)
72{
73 struct ptdesc *ptdesc;
74
75 ptdesc = pagetable_alloc_noprof(gfp, order: 0);
76 if (!ptdesc)
77 return NULL;
78 if (!pagetable_pte_ctor(mm, ptdesc)) {
79 pagetable_free(pt: ptdesc);
80 return NULL;
81 }
82
83 return ptdesc_page(ptdesc);
84}
85#define __pte_alloc_one(...) alloc_hooks(__pte_alloc_one_noprof(__VA_ARGS__))
86
87#ifndef __HAVE_ARCH_PTE_ALLOC_ONE
88/**
89 * pte_alloc_one - allocate a page for PTE-level user page table
90 * @mm: the mm_struct of the current context
91 *
92 * Allocate memory for a page table and ptdesc and runs pagetable_pte_ctor().
93 *
94 * Return: `struct page` referencing the ptdesc or %NULL on error
95 */
96static inline pgtable_t pte_alloc_one_noprof(struct mm_struct *mm)
97{
98 return __pte_alloc_one_noprof(mm, GFP_PGTABLE_USER);
99}
100#define pte_alloc_one(...) alloc_hooks(pte_alloc_one_noprof(__VA_ARGS__))
101#endif
102
103/*
104 * Should really implement gc for free page table pages. This could be
105 * done with a reference count in struct page.
106 */
107
108/**
109 * pte_free - free PTE-level user page table memory
110 * @mm: the mm_struct of the current context
111 * @pte_page: the `struct page` referencing the ptdesc
112 */
113static inline void pte_free(struct mm_struct *mm, struct page *pte_page)
114{
115 struct ptdesc *ptdesc = page_ptdesc(pte_page);
116
117 pagetable_dtor_free(ptdesc);
118}
119
120
121#if CONFIG_PGTABLE_LEVELS > 2
122
123#ifndef __HAVE_ARCH_PMD_ALLOC_ONE
124/**
125 * pmd_alloc_one - allocate memory for a PMD-level page table
126 * @mm: the mm_struct of the current context
127 *
128 * Allocate memory for a page table and ptdesc and runs pagetable_pmd_ctor().
129 *
130 * Allocations use %GFP_PGTABLE_USER in user context and
131 * %GFP_PGTABLE_KERNEL in kernel context.
132 *
133 * Return: pointer to the allocated memory or %NULL on error
134 */
135static inline pmd_t *pmd_alloc_one_noprof(struct mm_struct *mm, unsigned long addr)
136{
137 struct ptdesc *ptdesc;
138 gfp_t gfp = GFP_PGTABLE_USER;
139
140 if (mm == &init_mm)
141 gfp = GFP_PGTABLE_KERNEL;
142 ptdesc = pagetable_alloc_noprof(gfp, order: 0);
143 if (!ptdesc)
144 return NULL;
145 if (!pagetable_pmd_ctor(mm, ptdesc)) {
146 pagetable_free(pt: ptdesc);
147 return NULL;
148 }
149 return ptdesc_address(pt: ptdesc);
150}
151#define pmd_alloc_one(...) alloc_hooks(pmd_alloc_one_noprof(__VA_ARGS__))
152#endif
153
154#ifndef __HAVE_ARCH_PMD_FREE
155static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
156{
157 struct ptdesc *ptdesc = virt_to_ptdesc(x: pmd);
158
159 BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
160 pagetable_dtor_free(ptdesc);
161}
162#endif
163
164#endif /* CONFIG_PGTABLE_LEVELS > 2 */
165
166#if CONFIG_PGTABLE_LEVELS > 3
167
168static inline pud_t *__pud_alloc_one_noprof(struct mm_struct *mm, unsigned long addr)
169{
170 gfp_t gfp = GFP_PGTABLE_USER;
171 struct ptdesc *ptdesc;
172
173 if (mm == &init_mm)
174 gfp = GFP_PGTABLE_KERNEL;
175 gfp &= ~__GFP_HIGHMEM;
176
177 ptdesc = pagetable_alloc_noprof(gfp, order: 0);
178 if (!ptdesc)
179 return NULL;
180
181 pagetable_pud_ctor(ptdesc);
182 return ptdesc_address(pt: ptdesc);
183}
184#define __pud_alloc_one(...) alloc_hooks(__pud_alloc_one_noprof(__VA_ARGS__))
185
186#ifndef __HAVE_ARCH_PUD_ALLOC_ONE
187/**
188 * pud_alloc_one - allocate memory for a PUD-level page table
189 * @mm: the mm_struct of the current context
190 *
191 * Allocate memory for a page table using %GFP_PGTABLE_USER for user context
192 * and %GFP_PGTABLE_KERNEL for kernel context.
193 *
194 * Return: pointer to the allocated memory or %NULL on error
195 */
196static inline pud_t *pud_alloc_one_noprof(struct mm_struct *mm, unsigned long addr)
197{
198 return __pud_alloc_one_noprof(mm, addr);
199}
200#define pud_alloc_one(...) alloc_hooks(pud_alloc_one_noprof(__VA_ARGS__))
201#endif
202
203static inline void __pud_free(struct mm_struct *mm, pud_t *pud)
204{
205 struct ptdesc *ptdesc = virt_to_ptdesc(x: pud);
206
207 BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
208 pagetable_dtor_free(ptdesc);
209}
210
211#ifndef __HAVE_ARCH_PUD_FREE
212static inline void pud_free(struct mm_struct *mm, pud_t *pud)
213{
214 __pud_free(mm, pud);
215}
216#endif
217
218#endif /* CONFIG_PGTABLE_LEVELS > 3 */
219
220#if CONFIG_PGTABLE_LEVELS > 4
221
222static inline p4d_t *__p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long addr)
223{
224 gfp_t gfp = GFP_PGTABLE_USER;
225 struct ptdesc *ptdesc;
226
227 if (mm == &init_mm)
228 gfp = GFP_PGTABLE_KERNEL;
229 gfp &= ~__GFP_HIGHMEM;
230
231 ptdesc = pagetable_alloc_noprof(gfp, order: 0);
232 if (!ptdesc)
233 return NULL;
234
235 pagetable_p4d_ctor(ptdesc);
236 return ptdesc_address(pt: ptdesc);
237}
238#define __p4d_alloc_one(...) alloc_hooks(__p4d_alloc_one_noprof(__VA_ARGS__))
239
240#ifndef __HAVE_ARCH_P4D_ALLOC_ONE
241static inline p4d_t *p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long addr)
242{
243 return __p4d_alloc_one_noprof(mm, addr);
244}
245#define p4d_alloc_one(...) alloc_hooks(p4d_alloc_one_noprof(__VA_ARGS__))
246#endif
247
248static inline void __p4d_free(struct mm_struct *mm, p4d_t *p4d)
249{
250 struct ptdesc *ptdesc = virt_to_ptdesc(x: p4d);
251
252 BUG_ON((unsigned long)p4d & (PAGE_SIZE-1));
253 pagetable_dtor_free(ptdesc);
254}
255
256#ifndef __HAVE_ARCH_P4D_FREE
257static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
258{
259 if (!mm_p4d_folded(mm))
260 __p4d_free(mm, p4d);
261}
262#endif
263
264#endif /* CONFIG_PGTABLE_LEVELS > 4 */
265
266static inline pgd_t *__pgd_alloc_noprof(struct mm_struct *mm, unsigned int order)
267{
268 gfp_t gfp = GFP_PGTABLE_USER;
269 struct ptdesc *ptdesc;
270
271 if (mm == &init_mm)
272 gfp = GFP_PGTABLE_KERNEL;
273 gfp &= ~__GFP_HIGHMEM;
274
275 ptdesc = pagetable_alloc_noprof(gfp, order);
276 if (!ptdesc)
277 return NULL;
278
279 pagetable_pgd_ctor(ptdesc);
280 return ptdesc_address(pt: ptdesc);
281}
282#define __pgd_alloc(...) alloc_hooks(__pgd_alloc_noprof(__VA_ARGS__))
283
284static inline void __pgd_free(struct mm_struct *mm, pgd_t *pgd)
285{
286 struct ptdesc *ptdesc = virt_to_ptdesc(x: pgd);
287
288 BUG_ON((unsigned long)pgd & (PAGE_SIZE-1));
289 pagetable_dtor_free(ptdesc);
290}
291
292#ifndef __HAVE_ARCH_PGD_FREE
293static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
294{
295 __pgd_free(mm, pgd);
296}
297#endif
298
299#endif /* CONFIG_MMU */
300
301#endif /* __ASM_GENERIC_PGALLOC_H */
302