xref: /openbmc/linux/arch/xtensa/include/asm/pgalloc.h (revision b830f94f)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * include/asm-xtensa/pgalloc.h
4  *
5  * Copyright (C) 2001-2007 Tensilica Inc.
6  */
7 
8 #ifndef _XTENSA_PGALLOC_H
9 #define _XTENSA_PGALLOC_H
10 
11 #include <linux/highmem.h>
12 #include <linux/slab.h>
13 
14 /*
15  * Allocating and freeing a pmd is trivial: the 1-entry pmd is
16  * inside the pgd, so has no extra memory associated with it.
17  */
18 
19 #define pmd_populate_kernel(mm, pmdp, ptep)				     \
20 	(pmd_val(*(pmdp)) = ((unsigned long)ptep))
21 #define pmd_populate(mm, pmdp, page)					     \
22 	(pmd_val(*(pmdp)) = ((unsigned long)page_to_virt(page)))
23 #define pmd_pgtable(pmd) pmd_page(pmd)
24 
25 static inline pgd_t*
26 pgd_alloc(struct mm_struct *mm)
27 {
28 	return (pgd_t*) __get_free_pages(GFP_KERNEL | __GFP_ZERO, PGD_ORDER);
29 }
30 
31 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
32 {
33 	free_page((unsigned long)pgd);
34 }
35 
36 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
37 {
38 	pte_t *ptep;
39 	int i;
40 
41 	ptep = (pte_t *)__get_free_page(GFP_KERNEL);
42 	if (!ptep)
43 		return NULL;
44 	for (i = 0; i < 1024; i++)
45 		pte_clear(NULL, 0, ptep + i);
46 	return ptep;
47 }
48 
49 static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
50 {
51 	pte_t *pte;
52 	struct page *page;
53 
54 	pte = pte_alloc_one_kernel(mm);
55 	if (!pte)
56 		return NULL;
57 	page = virt_to_page(pte);
58 	if (!pgtable_page_ctor(page)) {
59 		__free_page(page);
60 		return NULL;
61 	}
62 	return page;
63 }
64 
65 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
66 {
67 	free_page((unsigned long)pte);
68 }
69 
70 static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
71 {
72 	pgtable_page_dtor(pte);
73 	__free_page(pte);
74 }
75 #define pmd_pgtable(pmd) pmd_page(pmd)
76 
77 #endif /* _XTENSA_PGALLOC_H */
78