xref: /openbmc/linux/arch/powerpc/include/asm/book3s/64/pgalloc.h (revision ca90578000afb0d8f177ea36f7259a9c3640cf49)
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/percpu.h>
13 
14 struct vmemmap_backing {
15 	struct vmemmap_backing *list;
16 	unsigned long phys;
17 	unsigned long virt_addr;
18 };
19 extern struct vmemmap_backing *vmemmap_list;
20 
21 /*
22  * Functions that deal with pagetables that could be at any level of
23  * the table need to be passed an "index_size" so they know how to
24  * handle allocation.  For PTE pages (which are linked to a struct
25  * page for now, and drawn from the main get_free_pages() pool), the
26  * allocation size will be (2^index_size * sizeof(pointer)) and
27  * allocations are drawn from the kmem_cache in PGT_CACHE(index_size).
28  *
29  * The maximum index size needs to be big enough to allow any
30  * pagetable sizes we need, but small enough to fit in the low bits of
31  * any page table pointer.  In other words all pagetables, even tiny
32  * ones, must be aligned to allow at least enough low 0 bits to
33  * contain this value.  This value is also used as a mask, so it must
34  * be one less than a power of two.
35  */
36 #define MAX_PGTABLE_INDEX_SIZE	0xf
37 
38 extern struct kmem_cache *pgtable_cache[];
39 #define PGT_CACHE(shift) ({				\
40 			BUG_ON(!(shift));		\
41 			pgtable_cache[(shift) - 1];	\
42 		})
43 
44 extern pte_t *pte_fragment_alloc(struct mm_struct *, unsigned long, int);
45 extern void pte_fragment_free(unsigned long *, int);
46 extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift);
47 #ifdef CONFIG_SMP
48 extern void __tlb_remove_table(void *_table);
49 #endif
50 
51 static inline pgd_t *radix__pgd_alloc(struct mm_struct *mm)
52 {
53 #ifdef CONFIG_PPC_64K_PAGES
54 	return (pgd_t *)__get_free_page(pgtable_gfp_flags(mm, PGALLOC_GFP));
55 #else
56 	struct page *page;
57 	page = alloc_pages(pgtable_gfp_flags(mm, PGALLOC_GFP | __GFP_RETRY_MAYFAIL),
58 				4);
59 	if (!page)
60 		return NULL;
61 	return (pgd_t *) page_address(page);
62 #endif
63 }
64 
65 static inline void radix__pgd_free(struct mm_struct *mm, pgd_t *pgd)
66 {
67 #ifdef CONFIG_PPC_64K_PAGES
68 	free_page((unsigned long)pgd);
69 #else
70 	free_pages((unsigned long)pgd, 4);
71 #endif
72 }
73 
74 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
75 {
76 	pgd_t *pgd;
77 
78 	if (radix_enabled())
79 		return radix__pgd_alloc(mm);
80 
81 	pgd = kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE),
82 			       pgtable_gfp_flags(mm, GFP_KERNEL));
83 	/*
84 	 * With hugetlb, we don't clear the second half of the page table.
85 	 * If we share the same slab cache with the pmd or pud level table,
86 	 * we need to make sure we zero out the full table on alloc.
87 	 * With 4K we don't store slot in the second half. Hence we don't
88 	 * need to do this for 4k.
89 	 */
90 #if defined(CONFIG_HUGETLB_PAGE) && defined(CONFIG_PPC_64K_PAGES) && \
91 	((H_PGD_INDEX_SIZE == H_PUD_CACHE_INDEX) ||		     \
92 	 (H_PGD_INDEX_SIZE == H_PMD_CACHE_INDEX))
93 	memset(pgd, 0, PGD_TABLE_SIZE);
94 #endif
95 	return pgd;
96 }
97 
98 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
99 {
100 	if (radix_enabled())
101 		return radix__pgd_free(mm, pgd);
102 	kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
103 }
104 
105 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
106 {
107 	pgd_set(pgd, __pgtable_ptr_val(pud) | PGD_VAL_BITS);
108 }
109 
110 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
111 {
112 	return kmem_cache_alloc(PGT_CACHE(PUD_CACHE_INDEX),
113 		pgtable_gfp_flags(mm, GFP_KERNEL));
114 }
115 
116 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
117 {
118 	kmem_cache_free(PGT_CACHE(PUD_CACHE_INDEX), pud);
119 }
120 
121 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
122 {
123 	pud_set(pud, __pgtable_ptr_val(pmd) | PUD_VAL_BITS);
124 }
125 
126 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
127                                   unsigned long address)
128 {
129 	/*
130 	 * By now all the pud entries should be none entries. So go
131 	 * ahead and flush the page walk cache
132 	 */
133 	flush_tlb_pgtable(tlb, address);
134 	pgtable_free_tlb(tlb, pud, PUD_CACHE_INDEX);
135 }
136 
137 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
138 {
139 	return kmem_cache_alloc(PGT_CACHE(PMD_CACHE_INDEX),
140 		pgtable_gfp_flags(mm, GFP_KERNEL));
141 }
142 
143 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
144 {
145 	kmem_cache_free(PGT_CACHE(PMD_CACHE_INDEX), pmd);
146 }
147 
148 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
149                                   unsigned long address)
150 {
151 	/*
152 	 * By now all the pud entries should be none entries. So go
153 	 * ahead and flush the page walk cache
154 	 */
155 	flush_tlb_pgtable(tlb, address);
156         return pgtable_free_tlb(tlb, pmd, PMD_CACHE_INDEX);
157 }
158 
159 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
160 				       pte_t *pte)
161 {
162 	pmd_set(pmd, __pgtable_ptr_val(pte) | PMD_VAL_BITS);
163 }
164 
165 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
166 				pgtable_t pte_page)
167 {
168 	pmd_set(pmd, __pgtable_ptr_val(pte_page) | PMD_VAL_BITS);
169 }
170 
171 static inline pgtable_t pmd_pgtable(pmd_t pmd)
172 {
173 	return (pgtable_t)pmd_page_vaddr(pmd);
174 }
175 
176 #ifdef CONFIG_PPC_4K_PAGES
177 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
178 					  unsigned long address)
179 {
180 	return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
181 }
182 
183 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
184 				      unsigned long address)
185 {
186 	struct page *page;
187 	pte_t *pte;
188 
189 	pte = (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO | __GFP_ACCOUNT);
190 	if (!pte)
191 		return NULL;
192 	page = virt_to_page(pte);
193 	if (!pgtable_page_ctor(page)) {
194 		__free_page(page);
195 		return NULL;
196 	}
197 	return pte;
198 }
199 #else /* if CONFIG_PPC_64K_PAGES */
200 
201 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
202 					  unsigned long address)
203 {
204 	return (pte_t *)pte_fragment_alloc(mm, address, 1);
205 }
206 
207 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
208 				      unsigned long address)
209 {
210 	return (pgtable_t)pte_fragment_alloc(mm, address, 0);
211 }
212 #endif
213 
214 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
215 {
216 	pte_fragment_free((unsigned long *)pte, 1);
217 }
218 
219 static inline void pte_free(struct mm_struct *mm, pgtable_t ptepage)
220 {
221 	pte_fragment_free((unsigned long *)ptepage, 0);
222 }
223 
224 static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t table,
225 				  unsigned long address)
226 {
227 	/*
228 	 * By now all the pud entries should be none entries. So go
229 	 * ahead and flush the page walk cache
230 	 */
231 	flush_tlb_pgtable(tlb, address);
232 	pgtable_free_tlb(tlb, table, 0);
233 }
234 
235 #define check_pgt_cache()	do { } while (0)
236 
237 #endif /* _ASM_POWERPC_BOOK3S_64_PGALLOC_H */
238