xref: /linux/arch/arm64/mm/flush.c (revision db6d8d5fdf9537641c76ba7f32e02b4bcc600972)
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 void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
29 		       unsigned long end)
30 {
31 	if (vma->vm_flags & VM_EXEC)
32 		__flush_icache_all();
33 }
34 
35 static void sync_icache_aliases(void *kaddr, unsigned long len)
36 {
37 	unsigned long addr = (unsigned long)kaddr;
38 
39 	if (icache_is_aliasing()) {
40 		__clean_dcache_area_pou(kaddr, len);
41 		__flush_icache_all();
42 	} else {
43 		flush_icache_range(addr, addr + len);
44 	}
45 }
46 
47 static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
48 				unsigned long uaddr, void *kaddr,
49 				unsigned long len)
50 {
51 	if (vma->vm_flags & VM_EXEC)
52 		sync_icache_aliases(kaddr, len);
53 }
54 
55 /*
56  * Copy user data from/to a page which is mapped into a different processes
57  * address space.  Really, we want to allow our "user space" model to handle
58  * this.
59  */
60 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
61 		       unsigned long uaddr, void *dst, const void *src,
62 		       unsigned long len)
63 {
64 	memcpy(dst, src, len);
65 	flush_ptrace_access(vma, page, uaddr, dst, len);
66 }
67 
68 void __sync_icache_dcache(pte_t pte, unsigned long addr)
69 {
70 	struct page *page = pte_page(pte);
71 
72 	if (!test_and_set_bit(PG_dcache_clean, &page->flags))
73 		sync_icache_aliases(page_address(page),
74 				    PAGE_SIZE << compound_order(page));
75 	else if (icache_is_aivivt())
76 		__flush_icache_all();
77 }
78 
79 /*
80  * This function is called when a page has been modified by the kernel. Mark
81  * it as dirty for later flushing when mapped in user space (if executable,
82  * see __sync_icache_dcache).
83  */
84 void flush_dcache_page(struct page *page)
85 {
86 	if (test_bit(PG_dcache_clean, &page->flags))
87 		clear_bit(PG_dcache_clean, &page->flags);
88 }
89 EXPORT_SYMBOL(flush_dcache_page);
90 
91 /*
92  * Additional functions defined in assembly.
93  */
94 EXPORT_SYMBOL(flush_icache_range);
95