1 /* 2 * Based on arch/arm/mm/flush.c 3 * 4 * Copyright (C) 1995-2002 Russell King 5 * Copyright (C) 2012 ARM Ltd. 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include <linux/export.h> 21 #include <linux/mm.h> 22 #include <linux/pagemap.h> 23 24 #include <asm/cacheflush.h> 25 #include <asm/cachetype.h> 26 #include <asm/tlbflush.h> 27 28 #include "mm.h" 29 30 void flush_cache_mm(struct mm_struct *mm) 31 { 32 } 33 34 void flush_cache_range(struct vm_area_struct *vma, unsigned long start, 35 unsigned long end) 36 { 37 if (vma->vm_flags & VM_EXEC) 38 __flush_icache_all(); 39 } 40 41 void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, 42 unsigned long pfn) 43 { 44 } 45 46 static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page, 47 unsigned long uaddr, void *kaddr, 48 unsigned long len) 49 { 50 if (vma->vm_flags & VM_EXEC) { 51 unsigned long addr = (unsigned long)kaddr; 52 if (icache_is_aliasing()) { 53 __flush_dcache_area(kaddr, len); 54 __flush_icache_all(); 55 } else { 56 flush_icache_range(addr, addr + len); 57 } 58 } 59 } 60 61 /* 62 * Copy user data from/to a page which is mapped into a different processes 63 * address space. Really, we want to allow our "user space" model to handle 64 * this. 65 * 66 * Note that this code needs to run on the current CPU. 67 */ 68 void copy_to_user_page(struct vm_area_struct *vma, struct page *page, 69 unsigned long uaddr, void *dst, const void *src, 70 unsigned long len) 71 { 72 #ifdef CONFIG_SMP 73 preempt_disable(); 74 #endif 75 memcpy(dst, src, len); 76 flush_ptrace_access(vma, page, uaddr, dst, len); 77 #ifdef CONFIG_SMP 78 preempt_enable(); 79 #endif 80 } 81 82 void __flush_dcache_page(struct page *page) 83 { 84 __flush_dcache_area(page_address(page), PAGE_SIZE); 85 } 86 87 void __sync_icache_dcache(pte_t pte, unsigned long addr) 88 { 89 unsigned long pfn; 90 struct page *page; 91 92 pfn = pte_pfn(pte); 93 if (!pfn_valid(pfn)) 94 return; 95 96 page = pfn_to_page(pfn); 97 if (!test_and_set_bit(PG_dcache_clean, &page->flags)) { 98 __flush_dcache_page(page); 99 __flush_icache_all(); 100 } else if (icache_is_aivivt()) { 101 __flush_icache_all(); 102 } 103 } 104 105 /* 106 * Ensure cache coherency between kernel mapping and userspace mapping of this 107 * page. 108 */ 109 void flush_dcache_page(struct page *page) 110 { 111 struct address_space *mapping; 112 113 /* 114 * The zero page is never written to, so never has any dirty cache 115 * lines, and therefore never needs to be flushed. 116 */ 117 if (page == ZERO_PAGE(0)) 118 return; 119 120 mapping = page_mapping(page); 121 if (mapping && mapping_mapped(mapping)) { 122 __flush_dcache_page(page); 123 __flush_icache_all(); 124 set_bit(PG_dcache_clean, &page->flags); 125 } else { 126 clear_bit(PG_dcache_clean, &page->flags); 127 } 128 } 129 EXPORT_SYMBOL(flush_dcache_page); 130 131 /* 132 * Additional functions defined in assembly. 133 */ 134 EXPORT_SYMBOL(flush_cache_all); 135 EXPORT_SYMBOL(flush_icache_range); 136