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/shm.h>
15 #include <asm/cacheflush.h>
16 #include <asm/system.h>
17 #include <asm/tlbflush.h>
19 #ifdef CONFIG_CPU_CACHE_VIPT
21 void flush_cache_mm(struct mm_struct *mm)
23 if (cache_is_vivt()) {
24 if (cpu_isset(smp_processor_id(), mm->cpu_vm_mask))
25 __cpuc_flush_user_all();
29 if (cache_is_vipt_aliasing()) {
30 asm( "mcr p15, 0, %0, c7, c14, 0\n"
31 " mcr p15, 0, %0, c7, c5, 0\n"
32 " mcr p15, 0, %0, c7, c10, 4"
39 void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
41 if (cache_is_vivt()) {
42 if (cpu_isset(smp_processor_id(), vma->vm_mm->cpu_vm_mask))
43 __cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end),
48 if (cache_is_vipt_aliasing()) {
49 asm( "mcr p15, 0, %0, c7, c14, 0\n"
50 " mcr p15, 0, %0, c7, c5, 0\n"
51 " mcr p15, 0, %0, c7, c10, 4"
58 void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn)
60 if (cache_is_vivt()) {
61 if (cpu_isset(smp_processor_id(), vma->vm_mm->cpu_vm_mask)) {
62 unsigned long addr = user_addr & PAGE_MASK;
63 __cpuc_flush_user_range(addr, addr + PAGE_SIZE, vma->vm_flags);
68 if (cache_is_vipt_aliasing())
69 flush_pfn_alias(pfn, user_addr);
72 #define ALIAS_FLUSH_START 0xffff4000
74 #define TOP_PTE(x) pte_offset_kernel(top_pmd, x)
76 static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr)
78 unsigned long to = ALIAS_FLUSH_START + (CACHE_COLOUR(vaddr) << PAGE_SHIFT);
80 set_pte(TOP_PTE(to), pfn_pte(pfn, PAGE_KERNEL));
81 flush_tlb_kernel_page(to);
83 asm( "mcrr p15, 0, %1, %0, c14\n"
84 " mcrr p15, 0, %1, %0, c5\n"
86 : "r" (to), "r" (to + PAGE_SIZE - L1_CACHE_BYTES)
90 #define flush_pfn_alias(pfn,vaddr) do { } while (0)
93 void __flush_dcache_page(struct address_space *mapping, struct page *page)
96 * Writeback any data associated with the kernel mapping of this
97 * page. This ensures that data in the physical page is mutually
98 * coherent with the kernels mapping.
100 __cpuc_flush_dcache_page(page_address(page));
103 * If this is a page cache page, and we have an aliasing VIPT cache,
104 * we only need to do one flush - which would be at the relevant
105 * userspace colour, which is congruent with page->index.
107 if (mapping && cache_is_vipt_aliasing())
108 flush_pfn_alias(page_to_pfn(page),
109 page->index << PAGE_CACHE_SHIFT);
112 static void __flush_dcache_aliases(struct address_space *mapping, struct page *page)
114 struct mm_struct *mm = current->active_mm;
115 struct vm_area_struct *mpnt;
116 struct prio_tree_iter iter;
120 * There are possible user space mappings of this page:
121 * - VIVT cache: we need to also write back and invalidate all user
122 * data in the current VM view associated with this page.
123 * - aliasing VIPT: we only need to find one mapping of this page.
125 pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
127 flush_dcache_mmap_lock(mapping);
128 vma_prio_tree_foreach(mpnt, &iter, &mapping->i_mmap, pgoff, pgoff) {
129 unsigned long offset;
132 * If this VMA is not in our MM, we can ignore it.
134 if (mpnt->vm_mm != mm)
136 if (!(mpnt->vm_flags & VM_MAYSHARE))
138 offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
139 flush_cache_page(mpnt, mpnt->vm_start + offset, page_to_pfn(page));
141 flush_dcache_mmap_unlock(mapping);
145 * Ensure cache coherency between kernel mapping and userspace mapping
148 * We have three cases to consider:
149 * - VIPT non-aliasing cache: fully coherent so nothing required.
150 * - VIVT: fully aliasing, so we need to handle every alias in our
152 * - VIPT aliasing: need to handle one alias in our current VM view.
154 * If we need to handle aliasing:
155 * If the page only exists in the page cache and there are no user
156 * space mappings, we can be lazy and remember that we may have dirty
157 * kernel cache lines for later. Otherwise, we assume we have
160 void flush_dcache_page(struct page *page)
162 struct address_space *mapping = page_mapping(page);
164 if (mapping && !mapping_mapped(mapping))
165 set_bit(PG_dcache_dirty, &page->flags);
167 __flush_dcache_page(mapping, page);
168 if (mapping && cache_is_vivt())
169 __flush_dcache_aliases(mapping, page);
172 EXPORT_SYMBOL(flush_dcache_page);
174 void flush_cache_mm(struct mm_struct *mm)
176 if (cache_is_vivt()) {
177 if (cpu_isset(smp_processor_id(), mm->cpu_vm_mask))
178 __cpuc_flush_user_all();
182 if (cache_is_vipt_aliasing()) {
183 asm( "mcr p15, 0, %0, c7, c14, 0\n"
184 " mcr p15, 0, %0, c7, c5, 0\n"
185 " mcr p15, 0, %0, c7, c10, 4"
192 void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
194 if (cache_is_vivt()) {
195 if (cpu_isset(smp_processor_id(), vma->vm_mm->cpu_vm_mask))
196 __cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end),
201 if (cache_is_vipt_aliasing()) {
202 asm( "mcr p15, 0, %0, c7, c14, 0\n"
203 " mcr p15, 0, %0, c7, c5, 0\n"
204 " mcr p15, 0, %0, c7, c10, 4"
211 void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn)
213 if (cache_is_vivt()) {
214 if (cpu_isset(smp_processor_id(), vma->vm_mm->cpu_vm_mask)) {
215 unsigned long addr = user_addr & PAGE_MASK;
216 __cpuc_flush_user_range(addr, addr + PAGE_SIZE, vma->vm_flags);
221 if (cache_is_vipt_aliasing())
222 flush_pfn_alias(pfn, user_addr);