blob: 4127a7bddfe5cef91f4a340cfe4225e6200330a6 [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,
37 struct page *from, unsigned long vaddr)
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);
Russell King063b0a42008-10-31 15:08:35 +000044 kunmap_atomic(kto, KM_USER1);
45 kunmap_atomic(kfrom, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046}
47
48/*
49 * Clear the user page. No aliasing to deal with so we can just
50 * attack the kernel's existing mapping of this page.
51 */
Russell King303c6442008-10-31 16:32:19 +000052static void v6_clear_user_highpage_nonaliasing(struct page *page, unsigned long vaddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070053{
Russell King303c6442008-10-31 16:32:19 +000054 void *kaddr = kmap_atomic(page, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 clear_page(kaddr);
Russell King303c6442008-10-31 16:32:19 +000056 kunmap_atomic(kaddr, KM_USER0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070057}
58
59/*
Russell King063b0a42008-10-31 15:08:35 +000060 * Discard data in the kernel mapping for the new page.
61 * FIXME: needs this MCRR to be supported.
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 */
Russell King063b0a42008-10-31 15:08:35 +000063static void discard_old_kernel_data(void *kto)
Linus Torvalds1da177e2005-04-16 15:20:36 -070064{
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 __asm__("mcrr p15, 0, %1, %0, c6 @ 0xec401f06"
66 :
67 : "r" (kto),
68 "r" ((unsigned long)kto + PAGE_SIZE - L1_CACHE_BYTES)
69 : "cc");
Russell King063b0a42008-10-31 15:08:35 +000070}
71
72/*
73 * Copy the page, taking account of the cache colour.
74 */
75static void v6_copy_user_highpage_aliasing(struct page *to,
76 struct page *from, unsigned long vaddr)
77{
78 unsigned int offset = CACHE_COLOUR(vaddr);
79 unsigned long kfrom, kto;
80
81 if (test_and_clear_bit(PG_dcache_dirty, &from->flags))
82 __flush_dcache_page(page_mapping(from), from);
83
84 /* FIXME: not highmem safe */
85 discard_old_kernel_data(page_address(to));
Linus Torvalds1da177e2005-04-16 15:20:36 -070086
87 /*
88 * Now copy the page using the same cache colour as the
89 * pages ultimate destination.
90 */
91 spin_lock(&v6_lock);
92
Russell King063b0a42008-10-31 15:08:35 +000093 set_pte_ext(TOP_PTE(from_address) + offset, pfn_pte(page_to_pfn(from), PAGE_KERNEL), 0);
94 set_pte_ext(TOP_PTE(to_address) + offset, pfn_pte(page_to_pfn(to), PAGE_KERNEL), 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
Russell King063b0a42008-10-31 15:08:35 +000096 kfrom = from_address + (offset << PAGE_SHIFT);
97 kto = to_address + (offset << PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -070098
Russell King063b0a42008-10-31 15:08:35 +000099 flush_tlb_kernel_page(kfrom);
100 flush_tlb_kernel_page(kto);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101
Russell King063b0a42008-10-31 15:08:35 +0000102 copy_page((void *)kto, (void *)kfrom);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103
104 spin_unlock(&v6_lock);
105}
106
107/*
108 * Clear the user page. We need to deal with the aliasing issues,
109 * so remap the kernel page into the same cache colour as the user
110 * page.
111 */
Russell King303c6442008-10-31 16:32:19 +0000112static void v6_clear_user_highpage_aliasing(struct page *page, unsigned long vaddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113{
Russell Kingb8a9b662005-06-20 11:31:09 +0100114 unsigned int offset = CACHE_COLOUR(vaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 unsigned long to = to_address + (offset << PAGE_SHIFT);
116
Russell King303c6442008-10-31 16:32:19 +0000117 /* FIXME: not highmem safe */
118 discard_old_kernel_data(page_address(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119
120 /*
121 * Now clear the page using the same cache colour as
122 * the pages ultimate destination.
123 */
124 spin_lock(&v6_lock);
125
Russell King303c6442008-10-31 16:32:19 +0000126 set_pte_ext(TOP_PTE(to_address) + offset, pfn_pte(page_to_pfn(page), PAGE_KERNEL), 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127 flush_tlb_kernel_page(to);
128 clear_page((void *)to);
129
130 spin_unlock(&v6_lock);
131}
132
133struct cpu_user_fns v6_user_fns __initdata = {
Russell King303c6442008-10-31 16:32:19 +0000134 .cpu_clear_user_highpage = v6_clear_user_highpage_nonaliasing,
Russell King063b0a42008-10-31 15:08:35 +0000135 .cpu_copy_user_highpage = v6_copy_user_highpage_nonaliasing,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136};
137
138static int __init v6_userpage_init(void)
139{
140 if (cache_is_vipt_aliasing()) {
Russell King303c6442008-10-31 16:32:19 +0000141 cpu_user.cpu_clear_user_highpage = v6_clear_user_highpage_aliasing;
Russell King063b0a42008-10-31 15:08:35 +0000142 cpu_user.cpu_copy_user_highpage = v6_copy_user_highpage_aliasing;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 }
144
145 return 0;
146}
147
Russell King08ee4e42005-05-10 17:30:47 +0100148core_initcall(v6_userpage_init);