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_range(struct vm_area_struct *vma, unsigned long start, 31 unsigned long end) 32 { 33 if (vma->vm_flags & VM_EXEC) 34 __flush_icache_all(); 35 } 36 37 static void sync_icache_aliases(void *kaddr, unsigned long len) 38 { 39 unsigned long addr = (unsigned long)kaddr; 40 41 if (icache_is_aliasing()) { 42 __clean_dcache_area_pou(kaddr, len); 43 __flush_icache_all(); 44 } else { 45 flush_icache_range(addr, addr + len); 46 } 47 } 48 49 static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page, 50 unsigned long uaddr, void *kaddr, 51 unsigned long len) 52 { 53 if (vma->vm_flags & VM_EXEC) 54 sync_icache_aliases(kaddr, len); 55 } 56 57 /* 58 * Copy user data from/to a page which is mapped into a different processes 59 * address space. Really, we want to allow our "user space" model to handle 60 * this. 61 * 62 * Note that this code needs to run on the current CPU. 63 */ 64 void copy_to_user_page(struct vm_area_struct *vma, struct page *page, 65 unsigned long uaddr, void *dst, const void *src, 66 unsigned long len) 67 { 68 preempt_disable(); 69 memcpy(dst, src, len); 70 flush_ptrace_access(vma, page, uaddr, dst, len); 71 preempt_enable(); 72 } 73 74 void __sync_icache_dcache(pte_t pte, unsigned long addr) 75 { 76 struct page *page = pte_page(pte); 77 78 /* no flushing needed for anonymous pages */ 79 if (!page_mapping(page)) 80 return; 81 82 if (!test_and_set_bit(PG_dcache_clean, &page->flags)) 83 sync_icache_aliases(page_address(page), 84 PAGE_SIZE << compound_order(page)); 85 else if (icache_is_aivivt()) 86 __flush_icache_all(); 87 } 88 89 /* 90 * This function is called when a page has been modified by the kernel. Mark 91 * it as dirty for later flushing when mapped in user space (if executable, 92 * see __sync_icache_dcache). 93 */ 94 void flush_dcache_page(struct page *page) 95 { 96 if (test_bit(PG_dcache_clean, &page->flags)) 97 clear_bit(PG_dcache_clean, &page->flags); 98 } 99 EXPORT_SYMBOL(flush_dcache_page); 100 101 /* 102 * Additional functions defined in assembly. 103 */ 104 EXPORT_SYMBOL(flush_icache_range); 105