xref: /linux/arch/nios2/mm/cacheflush.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2009, Wind River Systems Inc
7  * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
8  */
9 
10 #include <linux/export.h>
11 #include <linux/sched.h>
12 #include <linux/mm.h>
13 #include <linux/fs.h>
14 #include <linux/pagemap.h>
15 
16 #include <asm/cacheflush.h>
17 #include <asm/cpuinfo.h>
18 
19 static void __flush_dcache(unsigned long start, unsigned long end)
20 {
21 	unsigned long addr;
22 
23 	start &= ~(cpuinfo.dcache_line_size - 1);
24 	end += (cpuinfo.dcache_line_size - 1);
25 	end &= ~(cpuinfo.dcache_line_size - 1);
26 
27 	if (end > start + cpuinfo.dcache_size)
28 		end = start + cpuinfo.dcache_size;
29 
30 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
31 		__asm__ __volatile__ ("   flushd 0(%0)\n"
32 					: /* Outputs */
33 					: /* Inputs  */ "r"(addr)
34 					/* : No clobber */);
35 	}
36 }
37 
38 static void __invalidate_dcache(unsigned long start, unsigned long end)
39 {
40 	unsigned long addr;
41 
42 	start &= ~(cpuinfo.dcache_line_size - 1);
43 	end += (cpuinfo.dcache_line_size - 1);
44 	end &= ~(cpuinfo.dcache_line_size - 1);
45 
46 	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
47 		__asm__ __volatile__ ("   initda 0(%0)\n"
48 					: /* Outputs */
49 					: /* Inputs  */ "r"(addr)
50 					/* : No clobber */);
51 	}
52 }
53 
54 static void __flush_icache(unsigned long start, unsigned long end)
55 {
56 	unsigned long addr;
57 
58 	start &= ~(cpuinfo.icache_line_size - 1);
59 	end += (cpuinfo.icache_line_size - 1);
60 	end &= ~(cpuinfo.icache_line_size - 1);
61 
62 	if (end > start + cpuinfo.icache_size)
63 		end = start + cpuinfo.icache_size;
64 
65 	for (addr = start; addr < end; addr += cpuinfo.icache_line_size) {
66 		__asm__ __volatile__ ("   flushi %0\n"
67 					: /* Outputs */
68 					: /* Inputs  */ "r"(addr)
69 					/* : No clobber */);
70 	}
71 	__asm__ __volatile(" flushp\n");
72 }
73 
74 static void flush_aliases(struct address_space *mapping, struct folio *folio)
75 {
76 	struct mm_struct *mm = current->active_mm;
77 	struct vm_area_struct *vma;
78 	unsigned long flags;
79 	pgoff_t pgoff;
80 	unsigned long nr = folio_nr_pages(folio);
81 
82 	pgoff = folio->index;
83 
84 	flush_dcache_mmap_lock_irqsave(mapping, flags);
85 	vma_interval_tree_foreach(vma, &mapping->i_mmap, pgoff, pgoff + nr - 1) {
86 		unsigned long start;
87 
88 		if (vma->vm_mm != mm)
89 			continue;
90 		if (!(vma->vm_flags & VM_MAYSHARE))
91 			continue;
92 
93 		start = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
94 		flush_cache_range(vma, start, start + nr * PAGE_SIZE);
95 	}
96 	flush_dcache_mmap_unlock_irqrestore(mapping, flags);
97 }
98 
99 void flush_cache_all(void)
100 {
101 	__flush_dcache(0, cpuinfo.dcache_size);
102 	__flush_icache(0, cpuinfo.icache_size);
103 }
104 
105 void flush_cache_mm(struct mm_struct *mm)
106 {
107 	flush_cache_all();
108 }
109 
110 void flush_cache_dup_mm(struct mm_struct *mm)
111 {
112 	flush_cache_all();
113 }
114 
115 void flush_icache_range(unsigned long start, unsigned long end)
116 {
117 	__flush_dcache(start, end);
118 	__flush_icache(start, end);
119 }
120 
121 void flush_dcache_range(unsigned long start, unsigned long end)
122 {
123 	__flush_dcache(start, end);
124 	__flush_icache(start, end);
125 }
126 EXPORT_SYMBOL(flush_dcache_range);
127 
128 void invalidate_dcache_range(unsigned long start, unsigned long end)
129 {
130 	__invalidate_dcache(start, end);
131 }
132 EXPORT_SYMBOL(invalidate_dcache_range);
133 
134 void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
135 			unsigned long end)
136 {
137 	__flush_dcache(start, end);
138 	if (vma == NULL || (vma->vm_flags & VM_EXEC))
139 		__flush_icache(start, end);
140 }
141 
142 void flush_icache_pages(struct vm_area_struct *vma, struct page *page,
143 		unsigned int nr)
144 {
145 	unsigned long start = (unsigned long) page_address(page);
146 	unsigned long end = start + nr * PAGE_SIZE;
147 
148 	__flush_dcache(start, end);
149 	__flush_icache(start, end);
150 }
151 
152 void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
153 			unsigned long pfn)
154 {
155 	unsigned long start = vmaddr;
156 	unsigned long end = start + PAGE_SIZE;
157 
158 	__flush_dcache(start, end);
159 	if (vma->vm_flags & VM_EXEC)
160 		__flush_icache(start, end);
161 }
162 
163 static void __flush_dcache_folio(struct folio *folio)
164 {
165 	/*
166 	 * Writeback any data associated with the kernel mapping of this
167 	 * page.  This ensures that data in the physical page is mutually
168 	 * coherent with the kernels mapping.
169 	 */
170 	unsigned long start = (unsigned long)folio_address(folio);
171 
172 	__flush_dcache(start, start + folio_size(folio));
173 }
174 
175 void flush_dcache_folio(struct folio *folio)
176 {
177 	struct address_space *mapping;
178 
179 	/*
180 	 * The zero page is never written to, so never has any dirty
181 	 * cache lines, and therefore never needs to be flushed.
182 	 */
183 	if (is_zero_pfn(folio_pfn(folio)))
184 		return;
185 
186 	mapping = folio_flush_mapping(folio);
187 
188 	/* Flush this page if there are aliases. */
189 	if (mapping && !mapping_mapped(mapping)) {
190 		clear_bit(PG_dcache_clean, &folio->flags);
191 	} else {
192 		__flush_dcache_folio(folio);
193 		if (mapping) {
194 			unsigned long start = (unsigned long)folio_address(folio);
195 			flush_aliases(mapping, folio);
196 			flush_icache_range(start, start + folio_size(folio));
197 		}
198 		set_bit(PG_dcache_clean, &folio->flags);
199 	}
200 }
201 EXPORT_SYMBOL(flush_dcache_folio);
202 
203 void flush_dcache_page(struct page *page)
204 {
205 	flush_dcache_folio(page_folio(page));
206 }
207 EXPORT_SYMBOL(flush_dcache_page);
208 
209 void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma,
210 		unsigned long address, pte_t *ptep, unsigned int nr)
211 {
212 	pte_t pte = *ptep;
213 	unsigned long pfn = pte_pfn(pte);
214 	struct folio *folio;
215 	struct address_space *mapping;
216 
217 	reload_tlb_page(vma, address, pte);
218 
219 	if (!pfn_valid(pfn))
220 		return;
221 
222 	/*
223 	* The zero page is never written to, so never has any dirty
224 	* cache lines, and therefore never needs to be flushed.
225 	*/
226 	if (is_zero_pfn(pfn))
227 		return;
228 
229 	folio = page_folio(pfn_to_page(pfn));
230 	if (!test_and_set_bit(PG_dcache_clean, &folio->flags))
231 		__flush_dcache_folio(folio);
232 
233 	mapping = folio_flush_mapping(folio);
234 	if (mapping) {
235 		flush_aliases(mapping, folio);
236 		if (vma->vm_flags & VM_EXEC)
237 			flush_icache_pages(vma, &folio->page,
238 					folio_nr_pages(folio));
239 	}
240 }
241 
242 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
243 		    struct page *to)
244 {
245 	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
246 	__flush_icache(vaddr, vaddr + PAGE_SIZE);
247 	copy_page(vto, vfrom);
248 	__flush_dcache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
249 	__flush_icache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
250 }
251 
252 void clear_user_page(void *addr, unsigned long vaddr, struct page *page)
253 {
254 	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
255 	__flush_icache(vaddr, vaddr + PAGE_SIZE);
256 	clear_page(addr);
257 	__flush_dcache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
258 	__flush_icache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
259 }
260 
261 void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
262 			unsigned long user_vaddr,
263 			void *dst, void *src, int len)
264 {
265 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
266 	memcpy(dst, src, len);
267 	__flush_dcache((unsigned long)src, (unsigned long)src + len);
268 	if (vma->vm_flags & VM_EXEC)
269 		__flush_icache((unsigned long)src, (unsigned long)src + len);
270 }
271 
272 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
273 			unsigned long user_vaddr,
274 			void *dst, void *src, int len)
275 {
276 	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
277 	memcpy(dst, src, len);
278 	__flush_dcache((unsigned long)dst, (unsigned long)dst + len);
279 	if (vma->vm_flags & VM_EXEC)
280 		__flush_icache((unsigned long)dst, (unsigned long)dst + len);
281 }
282