Commit | Line | Data |
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1da177e4 | 1 | /* |
4baa9922 | 2 | * arch/arm/include/asm/tlb.h |
1da177e4 LT |
3 | * |
4 | * Copyright (C) 2002 Russell King | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * Experimentation shows that on a StrongARM, it appears to be faster | |
11 | * to use the "invalidate whole tlb" rather than "invalidate single | |
12 | * tlb" for this. | |
13 | * | |
14 | * This appears true for both the process fork+exit case, as well as | |
15 | * the munmap-large-area case. | |
16 | */ | |
17 | #ifndef __ASMARM_TLB_H | |
18 | #define __ASMARM_TLB_H | |
19 | ||
20 | #include <asm/cacheflush.h> | |
0157903e HC |
21 | |
22 | #ifndef CONFIG_MMU | |
23 | ||
24 | #include <linux/pagemap.h> | |
58e9c47f RK |
25 | |
26 | #define tlb_flush(tlb) ((void) tlb) | |
27 | ||
0157903e HC |
28 | #include <asm-generic/tlb.h> |
29 | ||
30 | #else /* !CONFIG_MMU */ | |
31 | ||
06824ba8 | 32 | #include <linux/swap.h> |
1da177e4 | 33 | #include <asm/pgalloc.h> |
06824ba8 RK |
34 | #include <asm/tlbflush.h> |
35 | ||
9e14f674 PZ |
36 | #define MMU_GATHER_BUNDLE 8 |
37 | ||
a0ad5496 SC |
38 | #ifdef CONFIG_HAVE_RCU_TABLE_FREE |
39 | static inline void __tlb_remove_table(void *_table) | |
40 | { | |
41 | free_page_and_swap_cache((struct page *)_table); | |
42 | } | |
43 | ||
44 | struct mmu_table_batch { | |
45 | struct rcu_head rcu; | |
46 | unsigned int nr; | |
47 | void *tables[0]; | |
48 | }; | |
49 | ||
50 | #define MAX_TABLE_BATCH \ | |
51 | ((PAGE_SIZE - sizeof(struct mmu_table_batch)) / sizeof(void *)) | |
52 | ||
53 | extern void tlb_table_flush(struct mmu_gather *tlb); | |
54 | extern void tlb_remove_table(struct mmu_gather *tlb, void *table); | |
55 | ||
56 | #define tlb_remove_entry(tlb, entry) tlb_remove_table(tlb, entry) | |
57 | #else | |
58 | #define tlb_remove_entry(tlb, entry) tlb_remove_page(tlb, entry) | |
59 | #endif /* CONFIG_HAVE_RCU_TABLE_FREE */ | |
60 | ||
1da177e4 LT |
61 | /* |
62 | * TLB handling. This allows us to remove pages from the page | |
63 | * tables, and efficiently handle the TLB issues. | |
64 | */ | |
65 | struct mmu_gather { | |
66 | struct mm_struct *mm; | |
a0ad5496 SC |
67 | #ifdef CONFIG_HAVE_RCU_TABLE_FREE |
68 | struct mmu_table_batch *batch; | |
69 | unsigned int need_flush; | |
70 | #endif | |
1da177e4 | 71 | unsigned int fullmm; |
06824ba8 | 72 | struct vm_area_struct *vma; |
2b047252 | 73 | unsigned long start, end; |
7fccfc00 AK |
74 | unsigned long range_start; |
75 | unsigned long range_end; | |
06824ba8 | 76 | unsigned int nr; |
9e14f674 PZ |
77 | unsigned int max; |
78 | struct page **pages; | |
79 | struct page *local[MMU_GATHER_BUNDLE]; | |
1da177e4 LT |
80 | }; |
81 | ||
82 | DECLARE_PER_CPU(struct mmu_gather, mmu_gathers); | |
83 | ||
06824ba8 RK |
84 | /* |
85 | * This is unnecessarily complex. There's three ways the TLB shootdown | |
86 | * code is used: | |
87 | * 1. Unmapping a range of vmas. See zap_page_range(), unmap_region(). | |
88 | * tlb->fullmm = 0, and tlb_start_vma/tlb_end_vma will be called. | |
89 | * tlb->vma will be non-NULL. | |
90 | * 2. Unmapping all vmas. See exit_mmap(). | |
91 | * tlb->fullmm = 1, and tlb_start_vma/tlb_end_vma will be called. | |
92 | * tlb->vma will be non-NULL. Additionally, page tables will be freed. | |
93 | * 3. Unmapping argument pages. See shift_arg_pages(). | |
94 | * tlb->fullmm = 0, but tlb_start_vma/tlb_end_vma will not be called. | |
95 | * tlb->vma will be NULL. | |
96 | */ | |
97 | static inline void tlb_flush(struct mmu_gather *tlb) | |
98 | { | |
99 | if (tlb->fullmm || !tlb->vma) | |
100 | flush_tlb_mm(tlb->mm); | |
101 | else if (tlb->range_end > 0) { | |
102 | flush_tlb_range(tlb->vma, tlb->range_start, tlb->range_end); | |
103 | tlb->range_start = TASK_SIZE; | |
104 | tlb->range_end = 0; | |
105 | } | |
106 | } | |
107 | ||
108 | static inline void tlb_add_flush(struct mmu_gather *tlb, unsigned long addr) | |
109 | { | |
110 | if (!tlb->fullmm) { | |
111 | if (addr < tlb->range_start) | |
112 | tlb->range_start = addr; | |
113 | if (addr + PAGE_SIZE > tlb->range_end) | |
114 | tlb->range_end = addr + PAGE_SIZE; | |
115 | } | |
116 | } | |
117 | ||
9e14f674 PZ |
118 | static inline void __tlb_alloc_page(struct mmu_gather *tlb) |
119 | { | |
120 | unsigned long addr = __get_free_pages(GFP_NOWAIT | __GFP_NOWARN, 0); | |
121 | ||
122 | if (addr) { | |
123 | tlb->pages = (void *)addr; | |
124 | tlb->max = PAGE_SIZE / sizeof(struct page *); | |
125 | } | |
126 | } | |
127 | ||
1cf35d47 | 128 | static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) |
06824ba8 RK |
129 | { |
130 | tlb_flush(tlb); | |
a0ad5496 SC |
131 | #ifdef CONFIG_HAVE_RCU_TABLE_FREE |
132 | tlb_table_flush(tlb); | |
133 | #endif | |
1cf35d47 LT |
134 | } |
135 | ||
136 | static inline void tlb_flush_mmu_free(struct mmu_gather *tlb) | |
137 | { | |
29eb7782 PZ |
138 | free_pages_and_swap_cache(tlb->pages, tlb->nr); |
139 | tlb->nr = 0; | |
140 | if (tlb->pages == tlb->local) | |
141 | __tlb_alloc_page(tlb); | |
06824ba8 RK |
142 | } |
143 | ||
1cf35d47 LT |
144 | static inline void tlb_flush_mmu(struct mmu_gather *tlb) |
145 | { | |
146 | tlb_flush_mmu_tlbonly(tlb); | |
147 | tlb_flush_mmu_free(tlb); | |
148 | } | |
149 | ||
9e14f674 | 150 | static inline void |
2b047252 | 151 | tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start, unsigned long end) |
1da177e4 | 152 | { |
1da177e4 | 153 | tlb->mm = mm; |
2b047252 LT |
154 | tlb->fullmm = !(start | (end+1)); |
155 | tlb->start = start; | |
156 | tlb->end = end; | |
06824ba8 | 157 | tlb->vma = NULL; |
9e14f674 PZ |
158 | tlb->max = ARRAY_SIZE(tlb->local); |
159 | tlb->pages = tlb->local; | |
06824ba8 | 160 | tlb->nr = 0; |
9e14f674 | 161 | __tlb_alloc_page(tlb); |
a0ad5496 SC |
162 | |
163 | #ifdef CONFIG_HAVE_RCU_TABLE_FREE | |
164 | tlb->batch = NULL; | |
165 | #endif | |
1da177e4 LT |
166 | } |
167 | ||
168 | static inline void | |
169 | tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end) | |
170 | { | |
06824ba8 | 171 | tlb_flush_mmu(tlb); |
1da177e4 LT |
172 | |
173 | /* keep the page table cache within bounds */ | |
174 | check_pgt_cache(); | |
15a23ffa | 175 | |
9e14f674 PZ |
176 | if (tlb->pages != tlb->local) |
177 | free_pages((unsigned long)tlb->pages, 0); | |
1da177e4 LT |
178 | } |
179 | ||
7fccfc00 AK |
180 | /* |
181 | * Memorize the range for the TLB flush. | |
182 | */ | |
183 | static inline void | |
184 | tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long addr) | |
185 | { | |
06824ba8 | 186 | tlb_add_flush(tlb, addr); |
7fccfc00 | 187 | } |
1da177e4 LT |
188 | |
189 | /* | |
190 | * In the case of tlb vma handling, we can optimise these away in the | |
191 | * case where we're doing a full MM flush. When we're doing a munmap, | |
192 | * the vmas are adjusted to only cover the region to be torn down. | |
193 | */ | |
194 | static inline void | |
195 | tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) | |
196 | { | |
7fccfc00 | 197 | if (!tlb->fullmm) { |
1da177e4 | 198 | flush_cache_range(vma, vma->vm_start, vma->vm_end); |
06824ba8 | 199 | tlb->vma = vma; |
7fccfc00 AK |
200 | tlb->range_start = TASK_SIZE; |
201 | tlb->range_end = 0; | |
202 | } | |
1da177e4 LT |
203 | } |
204 | ||
205 | static inline void | |
206 | tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) | |
207 | { | |
06824ba8 RK |
208 | if (!tlb->fullmm) |
209 | tlb_flush(tlb); | |
210 | } | |
211 | ||
9e14f674 | 212 | static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page) |
06824ba8 | 213 | { |
9e14f674 PZ |
214 | tlb->pages[tlb->nr++] = page; |
215 | VM_BUG_ON(tlb->nr > tlb->max); | |
216 | return tlb->max - tlb->nr; | |
217 | } | |
218 | ||
219 | static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page) | |
220 | { | |
221 | if (!__tlb_remove_page(tlb, page)) | |
222 | tlb_flush_mmu(tlb); | |
06824ba8 RK |
223 | } |
224 | ||
225 | static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte, | |
226 | unsigned long addr) | |
227 | { | |
228 | pgtable_page_dtor(pte); | |
6d3ec1ae | 229 | |
df547e08 WD |
230 | #ifdef CONFIG_ARM_LPAE |
231 | tlb_add_flush(tlb, addr); | |
232 | #else | |
6d3ec1ae CM |
233 | /* |
234 | * With the classic ARM MMU, a pte page has two corresponding pmd | |
235 | * entries, each covering 1MB. | |
236 | */ | |
237 | addr &= PMD_MASK; | |
238 | tlb_add_flush(tlb, addr + SZ_1M - PAGE_SIZE); | |
239 | tlb_add_flush(tlb, addr + SZ_1M); | |
df547e08 | 240 | #endif |
6d3ec1ae | 241 | |
a0ad5496 | 242 | tlb_remove_entry(tlb, pte); |
1da177e4 LT |
243 | } |
244 | ||
c9f27f10 CM |
245 | static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp, |
246 | unsigned long addr) | |
247 | { | |
248 | #ifdef CONFIG_ARM_LPAE | |
249 | tlb_add_flush(tlb, addr); | |
a0ad5496 | 250 | tlb_remove_entry(tlb, virt_to_page(pmdp)); |
c9f27f10 CM |
251 | #endif |
252 | } | |
253 | ||
8d962507 CM |
254 | static inline void |
255 | tlb_remove_pmd_tlb_entry(struct mmu_gather *tlb, pmd_t *pmdp, unsigned long addr) | |
256 | { | |
257 | tlb_add_flush(tlb, addr); | |
258 | } | |
259 | ||
06824ba8 | 260 | #define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr) |
c9f27f10 | 261 | #define pmd_free_tlb(tlb, pmdp, addr) __pmd_free_tlb(tlb, pmdp, addr) |
a32618d2 | 262 | #define pud_free_tlb(tlb, pudp, addr) pud_free((tlb)->mm, pudp) |
1da177e4 LT |
263 | |
264 | #define tlb_migrate_finish(mm) do { } while (0) | |
265 | ||
0157903e | 266 | #endif /* CONFIG_MMU */ |
1da177e4 | 267 | #endif |