xref: /linux/arch/m68k/include/asm/mcf_pgalloc.h (revision c79c3c34f75d72a066e292b10aa50fc758c97c89)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef M68K_MCF_PGALLOC_H
3 #define M68K_MCF_PGALLOC_H
4 
5 #include <asm/tlb.h>
6 #include <asm/tlbflush.h>
7 
8 extern inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
9 {
10 	free_page((unsigned long) pte);
11 }
12 
13 extern const char bad_pmd_string[];
14 
15 extern inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
16 {
17 	unsigned long page = __get_free_page(GFP_DMA);
18 
19 	if (!page)
20 		return NULL;
21 
22 	memset((void *)page, 0, PAGE_SIZE);
23 	return (pte_t *) (page);
24 }
25 
26 extern inline pmd_t *pmd_alloc_kernel(pgd_t *pgd, unsigned long address)
27 {
28 	return (pmd_t *) pgd;
29 }
30 
31 #define pmd_populate(mm, pmd, pte) (pmd_val(*pmd) = (unsigned long)(pte))
32 
33 #define pmd_populate_kernel pmd_populate
34 
35 #define pmd_pgtable(pmd) pfn_to_virt(pmd_val(pmd) >> PAGE_SHIFT)
36 
37 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pgtable,
38 				  unsigned long address)
39 {
40 	struct page *page = virt_to_page(pgtable);
41 
42 	pgtable_pte_page_dtor(page);
43 	__free_page(page);
44 }
45 
46 static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
47 {
48 	struct page *page = alloc_pages(GFP_DMA, 0);
49 	pte_t *pte;
50 
51 	if (!page)
52 		return NULL;
53 	if (!pgtable_pte_page_ctor(page)) {
54 		__free_page(page);
55 		return NULL;
56 	}
57 
58 	pte = page_address(page);
59 	clear_page(pte);
60 
61 	return pte;
62 }
63 
64 static inline void pte_free(struct mm_struct *mm, pgtable_t pgtable)
65 {
66 	struct page *page = virt_to_page(pgtable);
67 
68 	pgtable_pte_page_dtor(page);
69 	__free_page(page);
70 }
71 
72 /*
73  * In our implementation, each pgd entry contains 1 pmd that is never allocated
74  * or freed.  pgd_present is always 1, so this should never be called. -NL
75  */
76 #define pmd_free(mm, pmd) BUG()
77 
78 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
79 {
80 	free_page((unsigned long) pgd);
81 }
82 
83 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
84 {
85 	pgd_t *new_pgd;
86 
87 	new_pgd = (pgd_t *)__get_free_page(GFP_DMA | __GFP_NOWARN);
88 	if (!new_pgd)
89 		return NULL;
90 	memcpy(new_pgd, swapper_pg_dir, PTRS_PER_PGD * sizeof(pgd_t));
91 	memset(new_pgd, 0, PAGE_OFFSET >> PGDIR_SHIFT);
92 	return new_pgd;
93 }
94 
95 #endif /* M68K_MCF_PGALLOC_H */
96