2 * linux/arch/arm/mm/flush.c
4 * Copyright (C) 1995-2002 Russell King
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.
10 #include <linux/module.h>
12 #include <linux/pagemap.h>
13 #include <linux/highmem.h>
15 #include <asm/cacheflush.h>
16 #include <asm/cachetype.h>
17 #include <asm/highmem.h>
18 #include <asm/smp_plat.h>
19 #include <asm/tlbflush.h>
20 #include <linux/hugetlb.h>
24 #ifdef CONFIG_CPU_CACHE_VIPT
26 static void flush_pfn_alias(unsigned long pfn
, unsigned long vaddr
)
28 unsigned long to
= FLUSH_ALIAS_START
+ (CACHE_COLOUR(vaddr
) << PAGE_SHIFT
);
31 set_top_pte(to
, pfn_pte(pfn
, PAGE_KERNEL
));
33 asm( "mcrr p15, 0, %1, %0, c14\n"
34 " mcr p15, 0, %2, c7, c10, 4"
36 : "r" (to
), "r" (to
+ PAGE_SIZE
- L1_CACHE_BYTES
), "r" (zero
)
40 static void flush_icache_alias(unsigned long pfn
, unsigned long vaddr
, unsigned long len
)
42 unsigned long va
= FLUSH_ALIAS_START
+ (CACHE_COLOUR(vaddr
) << PAGE_SHIFT
);
43 unsigned long offset
= vaddr
& (PAGE_SIZE
- 1);
46 set_top_pte(va
, pfn_pte(pfn
, PAGE_KERNEL
));
48 flush_icache_range(to
, to
+ len
);
51 void flush_cache_mm(struct mm_struct
*mm
)
53 if (cache_is_vivt()) {
54 vivt_flush_cache_mm(mm
);
58 if (cache_is_vipt_aliasing()) {
59 asm( "mcr p15, 0, %0, c7, c14, 0\n"
60 " mcr p15, 0, %0, c7, c10, 4"
67 void flush_cache_range(struct vm_area_struct
*vma
, unsigned long start
, unsigned long end
)
69 if (cache_is_vivt()) {
70 vivt_flush_cache_range(vma
, start
, end
);
74 if (cache_is_vipt_aliasing()) {
75 asm( "mcr p15, 0, %0, c7, c14, 0\n"
76 " mcr p15, 0, %0, c7, c10, 4"
82 if (vma
->vm_flags
& VM_EXEC
)
86 void flush_cache_page(struct vm_area_struct
*vma
, unsigned long user_addr
, unsigned long pfn
)
88 if (cache_is_vivt()) {
89 vivt_flush_cache_page(vma
, user_addr
, pfn
);
93 if (cache_is_vipt_aliasing()) {
94 flush_pfn_alias(pfn
, user_addr
);
98 if (vma
->vm_flags
& VM_EXEC
&& icache_is_vivt_asid_tagged())
103 #define flush_pfn_alias(pfn,vaddr) do { } while (0)
104 #define flush_icache_alias(pfn,vaddr,len) do { } while (0)
107 #define FLAG_PA_IS_EXEC 1
108 #define FLAG_PA_CORE_IN_MM 2
110 static void flush_ptrace_access_other(void *args
)
112 __flush_icache_all();
116 void __flush_ptrace_access(struct page
*page
, unsigned long uaddr
, void *kaddr
,
117 unsigned long len
, unsigned int flags
)
119 if (cache_is_vivt()) {
120 if (flags
& FLAG_PA_CORE_IN_MM
) {
121 unsigned long addr
= (unsigned long)kaddr
;
122 __cpuc_coherent_kern_range(addr
, addr
+ len
);
127 if (cache_is_vipt_aliasing()) {
128 flush_pfn_alias(page_to_pfn(page
), uaddr
);
129 __flush_icache_all();
133 /* VIPT non-aliasing D-cache */
134 if (flags
& FLAG_PA_IS_EXEC
) {
135 unsigned long addr
= (unsigned long)kaddr
;
136 if (icache_is_vipt_aliasing())
137 flush_icache_alias(page_to_pfn(page
), uaddr
, len
);
139 __cpuc_coherent_kern_range(addr
, addr
+ len
);
140 if (cache_ops_need_broadcast())
141 smp_call_function(flush_ptrace_access_other
,
147 void flush_ptrace_access(struct vm_area_struct
*vma
, struct page
*page
,
148 unsigned long uaddr
, void *kaddr
, unsigned long len
)
150 unsigned int flags
= 0;
151 if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(vma
->vm_mm
)))
152 flags
|= FLAG_PA_CORE_IN_MM
;
153 if (vma
->vm_flags
& VM_EXEC
)
154 flags
|= FLAG_PA_IS_EXEC
;
155 __flush_ptrace_access(page
, uaddr
, kaddr
, len
, flags
);
158 void flush_uprobe_xol_access(struct page
*page
, unsigned long uaddr
,
159 void *kaddr
, unsigned long len
)
161 unsigned int flags
= FLAG_PA_CORE_IN_MM
|FLAG_PA_IS_EXEC
;
163 __flush_ptrace_access(page
, uaddr
, kaddr
, len
, flags
);
167 * Copy user data from/to a page which is mapped into a different
168 * processes address space. Really, we want to allow our "user
169 * space" model to handle this.
171 * Note that this code needs to run on the current CPU.
173 void copy_to_user_page(struct vm_area_struct
*vma
, struct page
*page
,
174 unsigned long uaddr
, void *dst
, const void *src
,
180 memcpy(dst
, src
, len
);
181 flush_ptrace_access(vma
, page
, uaddr
, dst
, len
);
187 void __flush_dcache_page(struct address_space
*mapping
, struct page
*page
)
190 * Writeback any data associated with the kernel mapping of this
191 * page. This ensures that data in the physical page is mutually
192 * coherent with the kernels mapping.
194 if (!PageHighMem(page
)) {
195 size_t page_size
= PAGE_SIZE
<< compound_order(page
);
196 __cpuc_flush_dcache_area(page_address(page
), page_size
);
199 if (cache_is_vipt_nonaliasing()) {
200 for (i
= 0; i
< (1 << compound_order(page
)); i
++) {
201 void *addr
= kmap_atomic(page
+ i
);
202 __cpuc_flush_dcache_area(addr
, PAGE_SIZE
);
206 for (i
= 0; i
< (1 << compound_order(page
)); i
++) {
207 void *addr
= kmap_high_get(page
+ i
);
209 __cpuc_flush_dcache_area(addr
, PAGE_SIZE
);
210 kunmap_high(page
+ i
);
217 * If this is a page cache page, and we have an aliasing VIPT cache,
218 * we only need to do one flush - which would be at the relevant
219 * userspace colour, which is congruent with page->index.
221 if (mapping
&& cache_is_vipt_aliasing())
222 flush_pfn_alias(page_to_pfn(page
),
223 page
->index
<< PAGE_CACHE_SHIFT
);
226 static void __flush_dcache_aliases(struct address_space
*mapping
, struct page
*page
)
228 struct mm_struct
*mm
= current
->active_mm
;
229 struct vm_area_struct
*mpnt
;
233 * There are possible user space mappings of this page:
234 * - VIVT cache: we need to also write back and invalidate all user
235 * data in the current VM view associated with this page.
236 * - aliasing VIPT: we only need to find one mapping of this page.
238 pgoff
= page
->index
<< (PAGE_CACHE_SHIFT
- PAGE_SHIFT
);
240 flush_dcache_mmap_lock(mapping
);
241 vma_interval_tree_foreach(mpnt
, &mapping
->i_mmap
, pgoff
, pgoff
) {
242 unsigned long offset
;
245 * If this VMA is not in our MM, we can ignore it.
247 if (mpnt
->vm_mm
!= mm
)
249 if (!(mpnt
->vm_flags
& VM_MAYSHARE
))
251 offset
= (pgoff
- mpnt
->vm_pgoff
) << PAGE_SHIFT
;
252 flush_cache_page(mpnt
, mpnt
->vm_start
+ offset
, page_to_pfn(page
));
254 flush_dcache_mmap_unlock(mapping
);
257 #if __LINUX_ARM_ARCH__ >= 6
258 void __sync_icache_dcache(pte_t pteval
)
262 struct address_space
*mapping
;
264 if (cache_is_vipt_nonaliasing() && !pte_exec(pteval
))
265 /* only flush non-aliasing VIPT caches for exec mappings */
267 pfn
= pte_pfn(pteval
);
271 page
= pfn_to_page(pfn
);
272 if (cache_is_vipt_aliasing())
273 mapping
= page_mapping(page
);
277 if (!test_and_set_bit(PG_dcache_clean
, &page
->flags
))
278 __flush_dcache_page(mapping
, page
);
280 if (pte_exec(pteval
))
281 __flush_icache_all();
286 * Ensure cache coherency between kernel mapping and userspace mapping
289 * We have three cases to consider:
290 * - VIPT non-aliasing cache: fully coherent so nothing required.
291 * - VIVT: fully aliasing, so we need to handle every alias in our
293 * - VIPT aliasing: need to handle one alias in our current VM view.
295 * If we need to handle aliasing:
296 * If the page only exists in the page cache and there are no user
297 * space mappings, we can be lazy and remember that we may have dirty
298 * kernel cache lines for later. Otherwise, we assume we have
301 * Note that we disable the lazy flush for SMP configurations where
302 * the cache maintenance operations are not automatically broadcasted.
304 void flush_dcache_page(struct page
*page
)
306 struct address_space
*mapping
;
309 * The zero page is never written to, so never has any dirty
310 * cache lines, and therefore never needs to be flushed.
312 if (page
== ZERO_PAGE(0))
315 mapping
= page_mapping(page
);
317 if (!cache_ops_need_broadcast() &&
318 mapping
&& !page_mapped(page
))
319 clear_bit(PG_dcache_clean
, &page
->flags
);
321 __flush_dcache_page(mapping
, page
);
322 if (mapping
&& cache_is_vivt())
323 __flush_dcache_aliases(mapping
, page
);
325 __flush_icache_all();
326 set_bit(PG_dcache_clean
, &page
->flags
);
329 EXPORT_SYMBOL(flush_dcache_page
);
332 * Ensure cache coherency for the kernel mapping of this page. We can
333 * assume that the page is pinned via kmap.
335 * If the page only exists in the page cache and there are no user
336 * space mappings, this is a no-op since the page was already marked
337 * dirty at creation. Otherwise, we need to flush the dirty kernel
338 * cache lines directly.
340 void flush_kernel_dcache_page(struct page
*page
)
342 if (cache_is_vivt() || cache_is_vipt_aliasing()) {
343 struct address_space
*mapping
;
345 mapping
= page_mapping(page
);
347 if (!mapping
|| mapping_mapped(mapping
)) {
350 addr
= page_address(page
);
352 * kmap_atomic() doesn't set the page virtual
353 * address for highmem pages, and
354 * kunmap_atomic() takes care of cache
357 if (!IS_ENABLED(CONFIG_HIGHMEM
) || addr
)
358 __cpuc_flush_dcache_area(addr
, PAGE_SIZE
);
362 EXPORT_SYMBOL(flush_kernel_dcache_page
);
365 * Flush an anonymous page so that users of get_user_pages()
366 * can safely access the data. The expected sequence is:
370 * memcpy() to/from page
371 * if written to page, flush_dcache_page()
373 void __flush_anon_page(struct vm_area_struct
*vma
, struct page
*page
, unsigned long vmaddr
)
377 /* VIPT non-aliasing caches need do nothing */
378 if (cache_is_vipt_nonaliasing())
382 * Write back and invalidate userspace mapping.
384 pfn
= page_to_pfn(page
);
385 if (cache_is_vivt()) {
386 flush_cache_page(vma
, vmaddr
, pfn
);
389 * For aliasing VIPT, we can flush an alias of the
390 * userspace address only.
392 flush_pfn_alias(pfn
, vmaddr
);
393 __flush_icache_all();
397 * Invalidate kernel mapping. No data should be contained
398 * in this mapping of the page. FIXME: this is overkill
399 * since we actually ask for a write-back and invalidate.
401 __cpuc_flush_dcache_area(page_address(page
), PAGE_SIZE
);