blob: bdba6c65c901a1c682f1aaf0fce3875ad8fa448b [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/arch/arm/mm/copypage-v6.c
3 *
4 * Copyright (C) 2002 Deep Blue Solutions Ltd, All Rights Reserved.
5 *
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.
9 */
10#include <linux/init.h>
11#include <linux/spinlock.h>
12#include <linux/mm.h>
Russell King063b0a42008-10-31 15:08:35 +000013#include <linux/highmem.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <asm/pgtable.h>
16#include <asm/shmparam.h>
17#include <asm/tlbflush.h>
18#include <asm/cacheflush.h>
Russell King46097c72008-08-10 18:10:19 +010019#include <asm/cachetype.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
Russell King1b2e2b72006-08-21 17:06:38 +010021#include "mm.h"
22
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#if SHMLBA > 16384
24#error FIX ME
25#endif
26
27#define from_address (0xffff8000)
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#define to_address (0xffffc000)
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
Linus Torvalds1da177e2005-04-16 15:20:36 -070030static DEFINE_SPINLOCK(v6_lock);
31
Linus Torvalds1da177e2005-04-16 15:20:36 -070032/*
33 * Copy the user page. No aliasing to deal with so we can just
34 * attack the kernel's existing mapping of these pages.
35 */
Russell King063b0a42008-10-31 15:08:35 +000036static void v6_copy_user_highpage_nonaliasing(struct page *to,
Russell Kingf00a75c2009-10-05 15:17:45 +010037 struct page *from, unsigned long vaddr, struct vm_area_struct *vma)
Linus Torvalds1da177e2005-04-16 15:20:36 -070038{
Russell King063b0a42008-10-31 15:08:35 +000039 void *kto, *kfrom;
40
41 kfrom = kmap_atomic(from, KM_USER0);
42 kto = kmap_atomic(to, KM_USER1);
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 copy_page(kto, kfrom);
Nicolas Pitre7e5a69e2010-03-29 21:46:02 +010044 __cpuc_flush_dcache_area(kto, PAGE_SIZE);
Russell King063b0a42008-10-31 15:08:35 +000045 kunmap_atomic(kto, KM_USER1);
46 kunmap_atomic(kfrom, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047}
48
49/*
50 * Clear the user page. No aliasing to deal with so we can just
51 * attack the kernel's existing mapping of this page.
52 */
Russell King303c6442008-10-31 16:32:19 +000053static void v6_clear_user_highpage_nonaliasing(struct page *page, unsigned long vaddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070054{
Russell King303c6442008-10-31 16:32:19 +000055 void *kaddr = kmap_atomic(page, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 clear_page(kaddr);
Russell King303c6442008-10-31 16:32:19 +000057 kunmap_atomic(kaddr, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058}
59
60/*
Russell King063b0a42008-10-31 15:08:35 +000061 * Discard data in the kernel mapping for the new page.
62 * FIXME: needs this MCRR to be supported.
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 */
Russell King063b0a42008-10-31 15:08:35 +000064static void discard_old_kernel_data(void *kto)
Linus Torvalds1da177e2005-04-16 15:20:36 -070065{
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 __asm__("mcrr p15, 0, %1, %0, c6 @ 0xec401f06"
67 :
68 : "r" (kto),
69 "r" ((unsigned long)kto + PAGE_SIZE - L1_CACHE_BYTES)
70 : "cc");
Russell King063b0a42008-10-31 15:08:35 +000071}
72
73/*
74 * Copy the page, taking account of the cache colour.
75 */
76static void v6_copy_user_highpage_aliasing(struct page *to,
Russell Kingf00a75c2009-10-05 15:17:45 +010077 struct page *from, unsigned long vaddr, struct vm_area_struct *vma)
Russell King063b0a42008-10-31 15:08:35 +000078{
79 unsigned int offset = CACHE_COLOUR(vaddr);
80 unsigned long kfrom, kto;
81
Catalin Marinasc0177802010-09-13 15:57:36 +010082 if (!test_and_set_bit(PG_dcache_clean, &from->flags))
Russell King063b0a42008-10-31 15:08:35 +000083 __flush_dcache_page(page_mapping(from), from);
84
85 /* FIXME: not highmem safe */
86 discard_old_kernel_data(page_address(to));
Linus Torvalds1da177e2005-04-16 15:20:36 -070087
88 /*
89 * Now copy the page using the same cache colour as the
90 * pages ultimate destination.
91 */
92 spin_lock(&v6_lock);
93
Russell King063b0a42008-10-31 15:08:35 +000094 set_pte_ext(TOP_PTE(from_address) + offset, pfn_pte(page_to_pfn(from), PAGE_KERNEL), 0);
95 set_pte_ext(TOP_PTE(to_address) + offset, pfn_pte(page_to_pfn(to), PAGE_KERNEL), 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070096
Russell King063b0a42008-10-31 15:08:35 +000097 kfrom = from_address + (offset << PAGE_SHIFT);
98 kto = to_address + (offset << PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099
Russell King063b0a42008-10-31 15:08:35 +0000100 flush_tlb_kernel_page(kfrom);
101 flush_tlb_kernel_page(kto);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
Russell King063b0a42008-10-31 15:08:35 +0000103 copy_page((void *)kto, (void *)kfrom);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104
105 spin_unlock(&v6_lock);
106}
107
108/*
109 * Clear the user page. We need to deal with the aliasing issues,
110 * so remap the kernel page into the same cache colour as the user
111 * page.
112 */
Russell King303c6442008-10-31 16:32:19 +0000113static void v6_clear_user_highpage_aliasing(struct page *page, unsigned long vaddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114{
Russell Kingb8a9b662005-06-20 11:31:09 +0100115 unsigned int offset = CACHE_COLOUR(vaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 unsigned long to = to_address + (offset << PAGE_SHIFT);
117
Russell King303c6442008-10-31 16:32:19 +0000118 /* FIXME: not highmem safe */
119 discard_old_kernel_data(page_address(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
121 /*
122 * Now clear the page using the same cache colour as
123 * the pages ultimate destination.
124 */
125 spin_lock(&v6_lock);
126
Russell King303c6442008-10-31 16:32:19 +0000127 set_pte_ext(TOP_PTE(to_address) + offset, pfn_pte(page_to_pfn(page), PAGE_KERNEL), 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 flush_tlb_kernel_page(to);
129 clear_page((void *)to);
130
131 spin_unlock(&v6_lock);
132}
133
134struct cpu_user_fns v6_user_fns __initdata = {
Russell King303c6442008-10-31 16:32:19 +0000135 .cpu_clear_user_highpage = v6_clear_user_highpage_nonaliasing,
Russell King063b0a42008-10-31 15:08:35 +0000136 .cpu_copy_user_highpage = v6_copy_user_highpage_nonaliasing,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137};
138
139static int __init v6_userpage_init(void)
140{
141 if (cache_is_vipt_aliasing()) {
Russell King303c6442008-10-31 16:32:19 +0000142 cpu_user.cpu_clear_user_highpage = v6_clear_user_highpage_aliasing;
Russell King063b0a42008-10-31 15:08:35 +0000143 cpu_user.cpu_copy_user_highpage = v6_copy_user_highpage_aliasing;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 }
145
146 return 0;
147}
148
Russell King08ee4e42005-05-10 17:30:47 +0100149core_initcall(v6_userpage_init);