1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _ASM_POWERPC_BOOK3S_64_PGALLOC_H
3 #define _ASM_POWERPC_BOOK3S_64_PGALLOC_H
4 /*
5  */
6 
7 #include <linux/slab.h>
8 #include <linux/cpumask.h>
9 #include <linux/kmemleak.h>
10 #include <linux/percpu.h>
11 
12 struct vmemmap_backing {
13 	struct vmemmap_backing *list;
14 	unsigned long phys;
15 	unsigned long virt_addr;
16 };
17 extern struct vmemmap_backing *vmemmap_list;
18 
19 extern pmd_t *pmd_fragment_alloc(struct mm_struct *, unsigned long);
20 extern void pmd_fragment_free(unsigned long *);
21 extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift);
22 #ifdef CONFIG_SMP
23 extern void __tlb_remove_table(void *_table);
24 #endif
25 void pte_frag_destroy(void *pte_frag);
26 
27 static inline pgd_t *radix__pgd_alloc(struct mm_struct *mm)
28 {
29 #ifdef CONFIG_PPC_64K_PAGES
30 	return (pgd_t *)__get_free_page(pgtable_gfp_flags(mm, PGALLOC_GFP));
31 #else
32 	struct page *page;
33 	page = alloc_pages(pgtable_gfp_flags(mm, PGALLOC_GFP | __GFP_RETRY_MAYFAIL),
34 				4);
35 	if (!page)
36 		return NULL;
37 	return (pgd_t *) page_address(page);
38 #endif
39 }
40 
41 static inline void radix__pgd_free(struct mm_struct *mm, pgd_t *pgd)
42 {
43 #ifdef CONFIG_PPC_64K_PAGES
44 	free_page((unsigned long)pgd);
45 #else
46 	free_pages((unsigned long)pgd, 4);
47 #endif
48 }
49 
50 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
51 {
52 	pgd_t *pgd;
53 
54 	if (radix_enabled())
55 		return radix__pgd_alloc(mm);
56 
57 	pgd = kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
58 			       pgtable_gfp_flags(mm, GFP_KERNEL));
59 	if (unlikely(!pgd))
60 		return pgd;
61 
62 	/*
63 	 * Don't scan the PGD for pointers, it contains references to PUDs but
64 	 * those references are not full pointers and so can't be recognised by
65 	 * kmemleak.
66 	 */
67 	kmemleak_no_scan(pgd);
68 
69 	/*
70 	 * With hugetlb, we don't clear the second half of the page table.
71 	 * If we share the same slab cache with the pmd or pud level table,
72 	 * we need to make sure we zero out the full table on alloc.
73 	 * With 4K we don't store slot in the second half. Hence we don't
74 	 * need to do this for 4k.
75 	 */
76 #if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_PPC_64K_PAGES) && \
77 	(H_PGD_INDEX_SIZE == H_PUD_CACHE_INDEX)
78 	memset(pgd, 0, PGD_TABLE_SIZE);
79 #endif
80 	return pgd;
81 }
82 
83 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
84 {
85 	if (radix_enabled())
86 		return radix__pgd_free(mm, pgd);
87 	kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
88 }
89 
90 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
91 {
92 	*pgd =  __pgd(__pgtable_ptr_val(pud) | PGD_VAL_BITS);
93 }
94 
95 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
96 {
97 	pud_t *pud;
98 
99 	pud = kmem_cache_alloc(PGT_CACHE(PUD_CACHE_INDEX),
100 			       pgtable_gfp_flags(mm, GFP_KERNEL));
101 	/*
102 	 * Tell kmemleak to ignore the PUD, that means don't scan it for
103 	 * pointers and don't consider it a leak. PUDs are typically only
104 	 * referred to by their PGD, but kmemleak is not able to recognise those
105 	 * as pointers, leading to false leak reports.
106 	 */
107 	kmemleak_ignore(pud);
108 
109 	return pud;
110 }
111 
112 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
113 {
114 	kmem_cache_free(PGT_CACHE(PUD_CACHE_INDEX), pud);
115 }
116 
117 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
118 {
119 	*pud = __pud(__pgtable_ptr_val(pmd) | PUD_VAL_BITS);
120 }
121 
122 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
123 				  unsigned long address)
124 {
125 	/*
126 	 * By now all the pud entries should be none entries. So go
127 	 * ahead and flush the page walk cache
128 	 */
129 	flush_tlb_pgtable(tlb, address);
130 	pgtable_free_tlb(tlb, pud, PUD_INDEX);
131 }
132 
133 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
134 {
135 	return pmd_fragment_alloc(mm, addr);
136 }
137 
138 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
139 {
140 	pmd_fragment_free((unsigned long *)pmd);
141 }
142 
143 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
144 				  unsigned long address)
145 {
146 	/*
147 	 * By now all the pud entries should be none entries. So go
148 	 * ahead and flush the page walk cache
149 	 */
150 	flush_tlb_pgtable(tlb, address);
151 	return pgtable_free_tlb(tlb, pmd, PMD_INDEX);
152 }
153 
154 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
155 				       pte_t *pte)
156 {
157 	*pmd = __pmd(__pgtable_ptr_val(pte) | PMD_VAL_BITS);
158 }
159 
160 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
161 				pgtable_t pte_page)
162 {
163 	*pmd = __pmd(__pgtable_ptr_val(pte_page) | PMD_VAL_BITS);
164 }
165 
166 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
167 				  unsigned long address)
168 {
169 	/*
170 	 * By now all the pud entries should be none entries. So go
171 	 * ahead and flush the page walk cache
172 	 */
173 	flush_tlb_pgtable(tlb, address);
174 	pgtable_free_tlb(tlb, table, PTE_INDEX);
175 }
176 
177 extern atomic_long_t direct_pages_count[MMU_PAGE_COUNT];
178 static inline void update_page_count(int psize, long count)
179 {
180 	if (IS_ENABLED(CONFIG_PROC_FS))
181 		atomic_long_add(count, &direct_pages_count[psize]);
182 }
183 
184 #endif /* _ASM_POWERPC_BOOK3S_64_PGALLOC_H */
185