1 #ifndef _ASM_POWERPC_BOOK3S_64_PGALLOC_H
2 #define _ASM_POWERPC_BOOK3S_64_PGALLOC_H
3 /*
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  */
9 
10 #include <linux/slab.h>
11 #include <linux/cpumask.h>
12 #include <linux/kmemleak.h>
13 #include <linux/percpu.h>
14 
15 struct vmemmap_backing {
16 	struct vmemmap_backing *list;
17 	unsigned long phys;
18 	unsigned long virt_addr;
19 };
20 extern struct vmemmap_backing *vmemmap_list;
21 
22 extern pmd_t *pmd_fragment_alloc(struct mm_struct *, unsigned long);
23 extern void pmd_fragment_free(unsigned long *);
24 extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift);
25 #ifdef CONFIG_SMP
26 extern void __tlb_remove_table(void *_table);
27 #endif
28 void pte_frag_destroy(void *pte_frag);
29 
30 static inline pgd_t *radix__pgd_alloc(struct mm_struct *mm)
31 {
32 #ifdef CONFIG_PPC_64K_PAGES
33 	return (pgd_t *)__get_free_page(pgtable_gfp_flags(mm, PGALLOC_GFP));
34 #else
35 	struct page *page;
36 	page = alloc_pages(pgtable_gfp_flags(mm, PGALLOC_GFP | __GFP_RETRY_MAYFAIL),
37 				4);
38 	if (!page)
39 		return NULL;
40 	return (pgd_t *) page_address(page);
41 #endif
42 }
43 
44 static inline void radix__pgd_free(struct mm_struct *mm, pgd_t *pgd)
45 {
46 #ifdef CONFIG_PPC_64K_PAGES
47 	free_page((unsigned long)pgd);
48 #else
49 	free_pages((unsigned long)pgd, 4);
50 #endif
51 }
52 
53 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
54 {
55 	pgd_t *pgd;
56 
57 	if (radix_enabled())
58 		return radix__pgd_alloc(mm);
59 
60 	pgd = kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
61 			       pgtable_gfp_flags(mm, GFP_KERNEL));
62 	if (unlikely(!pgd))
63 		return pgd;
64 
65 	/*
66 	 * Don't scan the PGD for pointers, it contains references to PUDs but
67 	 * those references are not full pointers and so can't be recognised by
68 	 * kmemleak.
69 	 */
70 	kmemleak_no_scan(pgd);
71 
72 	/*
73 	 * With hugetlb, we don't clear the second half of the page table.
74 	 * If we share the same slab cache with the pmd or pud level table,
75 	 * we need to make sure we zero out the full table on alloc.
76 	 * With 4K we don't store slot in the second half. Hence we don't
77 	 * need to do this for 4k.
78 	 */
79 #if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_PPC_64K_PAGES) && \
80 	(H_PGD_INDEX_SIZE == H_PUD_CACHE_INDEX)
81 	memset(pgd, 0, PGD_TABLE_SIZE);
82 #endif
83 	return pgd;
84 }
85 
86 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
87 {
88 	if (radix_enabled())
89 		return radix__pgd_free(mm, pgd);
90 	kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
91 }
92 
93 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
94 {
95 	*pgd =  __pgd(__pgtable_ptr_val(pud) | PGD_VAL_BITS);
96 }
97 
98 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
99 {
100 	pud_t *pud;
101 
102 	pud = kmem_cache_alloc(PGT_CACHE(PUD_CACHE_INDEX),
103 			       pgtable_gfp_flags(mm, GFP_KERNEL));
104 	/*
105 	 * Tell kmemleak to ignore the PUD, that means don't scan it for
106 	 * pointers and don't consider it a leak. PUDs are typically only
107 	 * referred to by their PGD, but kmemleak is not able to recognise those
108 	 * as pointers, leading to false leak reports.
109 	 */
110 	kmemleak_ignore(pud);
111 
112 	return pud;
113 }
114 
115 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
116 {
117 	kmem_cache_free(PGT_CACHE(PUD_CACHE_INDEX), pud);
118 }
119 
120 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
121 {
122 	*pud = __pud(__pgtable_ptr_val(pmd) | PUD_VAL_BITS);
123 }
124 
125 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
126 				  unsigned long address)
127 {
128 	/*
129 	 * By now all the pud entries should be none entries. So go
130 	 * ahead and flush the page walk cache
131 	 */
132 	flush_tlb_pgtable(tlb, address);
133 	pgtable_free_tlb(tlb, pud, PUD_INDEX);
134 }
135 
136 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
137 {
138 	return pmd_fragment_alloc(mm, addr);
139 }
140 
141 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
142 {
143 	pmd_fragment_free((unsigned long *)pmd);
144 }
145 
146 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
147 				  unsigned long address)
148 {
149 	/*
150 	 * By now all the pud entries should be none entries. So go
151 	 * ahead and flush the page walk cache
152 	 */
153 	flush_tlb_pgtable(tlb, address);
154 	return pgtable_free_tlb(tlb, pmd, PMD_INDEX);
155 }
156 
157 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
158 				       pte_t *pte)
159 {
160 	*pmd = __pmd(__pgtable_ptr_val(pte) | PMD_VAL_BITS);
161 }
162 
163 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
164 				pgtable_t pte_page)
165 {
166 	*pmd = __pmd(__pgtable_ptr_val(pte_page) | PMD_VAL_BITS);
167 }
168 
169 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
170 				  unsigned long address)
171 {
172 	/*
173 	 * By now all the pud entries should be none entries. So go
174 	 * ahead and flush the page walk cache
175 	 */
176 	flush_tlb_pgtable(tlb, address);
177 	pgtable_free_tlb(tlb, table, PTE_INDEX);
178 }
179 
180 extern atomic_long_t direct_pages_count[MMU_PAGE_COUNT];
181 static inline void update_page_count(int psize, long count)
182 {
183 	if (IS_ENABLED(CONFIG_PROC_FS))
184 		atomic_long_add(count, &direct_pages_count[psize]);
185 }
186 
187 #endif /* _ASM_POWERPC_BOOK3S_64_PGALLOC_H */
188