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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
Thomas Gleixnerbd31b852009-07-03 08:44:46 -050027static DEFINE_RAW_SPINLOCK(v6_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
Linus Torvalds1da177e2005-04-16 15:20:36 -070029/*
30 * Copy the user page. No aliasing to deal with so we can just
31 * attack the kernel's existing mapping of these pages.
32 */
Russell King063b0a42008-10-31 15:08:35 +000033static void v6_copy_user_highpage_nonaliasing(struct page *to,
Russell Kingf00a75c2009-10-05 15:17:45 +010034 struct page *from, unsigned long vaddr, struct vm_area_struct *vma)
Linus Torvalds1da177e2005-04-16 15:20:36 -070035{
Russell King063b0a42008-10-31 15:08:35 +000036 void *kto, *kfrom;
37
Cong Wang5472e862011-11-25 23:14:15 +080038 kfrom = kmap_atomic(from);
39 kto = kmap_atomic(to);
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 copy_page(kto, kfrom);
Cong Wang5472e862011-11-25 23:14:15 +080041 kunmap_atomic(kto);
42 kunmap_atomic(kfrom);
Linus Torvalds1da177e2005-04-16 15:20:36 -070043}
44
45/*
46 * Clear the user page. No aliasing to deal with so we can just
47 * attack the kernel's existing mapping of this page.
48 */
Russell King303c6442008-10-31 16:32:19 +000049static void v6_clear_user_highpage_nonaliasing(struct page *page, unsigned long vaddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -070050{
Cong Wang5472e862011-11-25 23:14:15 +080051 void *kaddr = kmap_atomic(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 clear_page(kaddr);
Cong Wang5472e862011-11-25 23:14:15 +080053 kunmap_atomic(kaddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -070054}
55
56/*
Russell King063b0a42008-10-31 15:08:35 +000057 * Discard data in the kernel mapping for the new page.
58 * FIXME: needs this MCRR to be supported.
Linus Torvalds1da177e2005-04-16 15:20:36 -070059 */
Russell King063b0a42008-10-31 15:08:35 +000060static void discard_old_kernel_data(void *kto)
Linus Torvalds1da177e2005-04-16 15:20:36 -070061{
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 __asm__("mcrr p15, 0, %1, %0, c6 @ 0xec401f06"
63 :
64 : "r" (kto),
65 "r" ((unsigned long)kto + PAGE_SIZE - L1_CACHE_BYTES)
66 : "cc");
Russell King063b0a42008-10-31 15:08:35 +000067}
68
69/*
70 * Copy the page, taking account of the cache colour.
71 */
72static void v6_copy_user_highpage_aliasing(struct page *to,
Russell Kingf00a75c2009-10-05 15:17:45 +010073 struct page *from, unsigned long vaddr, struct vm_area_struct *vma)
Russell King063b0a42008-10-31 15:08:35 +000074{
75 unsigned int offset = CACHE_COLOUR(vaddr);
76 unsigned long kfrom, kto;
77
Catalin Marinasc0177802010-09-13 15:57:36 +010078 if (!test_and_set_bit(PG_dcache_clean, &from->flags))
Russell King063b0a42008-10-31 15:08:35 +000079 __flush_dcache_page(page_mapping(from), from);
80
81 /* FIXME: not highmem safe */
82 discard_old_kernel_data(page_address(to));
Linus Torvalds1da177e2005-04-16 15:20:36 -070083
84 /*
85 * Now copy the page using the same cache colour as the
86 * pages ultimate destination.
87 */
Thomas Gleixnerbd31b852009-07-03 08:44:46 -050088 raw_spin_lock(&v6_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070089
Russell Kingde27c302011-07-02 14:46:27 +010090 kfrom = COPYPAGE_V6_FROM + (offset << PAGE_SHIFT);
91 kto = COPYPAGE_V6_TO + (offset << PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -070092
Russell King67ece142011-07-02 15:20:44 +010093 set_top_pte(kfrom, mk_pte(from, PAGE_KERNEL));
94 set_top_pte(kto, mk_pte(to, PAGE_KERNEL));
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
Russell King063b0a42008-10-31 15:08:35 +000096 copy_page((void *)kto, (void *)kfrom);
Linus Torvalds1da177e2005-04-16 15:20:36 -070097
Thomas Gleixnerbd31b852009-07-03 08:44:46 -050098 raw_spin_unlock(&v6_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099}
100
101/*
102 * Clear the user page. We need to deal with the aliasing issues,
103 * so remap the kernel page into the same cache colour as the user
104 * page.
105 */
Russell King303c6442008-10-31 16:32:19 +0000106static void v6_clear_user_highpage_aliasing(struct page *page, unsigned long vaddr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107{
Russell Kingde27c302011-07-02 14:46:27 +0100108 unsigned long to = COPYPAGE_V6_TO + (CACHE_COLOUR(vaddr) << PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
Russell King303c6442008-10-31 16:32:19 +0000110 /* FIXME: not highmem safe */
111 discard_old_kernel_data(page_address(page));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112
113 /*
114 * Now clear the page using the same cache colour as
115 * the pages ultimate destination.
116 */
Thomas Gleixnerbd31b852009-07-03 08:44:46 -0500117 raw_spin_lock(&v6_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118
Russell King67ece142011-07-02 15:20:44 +0100119 set_top_pte(to, mk_pte(page, PAGE_KERNEL));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 clear_page((void *)to);
121
Thomas Gleixnerbd31b852009-07-03 08:44:46 -0500122 raw_spin_unlock(&v6_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123}
124
125struct cpu_user_fns v6_user_fns __initdata = {
Russell King303c6442008-10-31 16:32:19 +0000126 .cpu_clear_user_highpage = v6_clear_user_highpage_nonaliasing,
Russell King063b0a42008-10-31 15:08:35 +0000127 .cpu_copy_user_highpage = v6_copy_user_highpage_nonaliasing,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128};
129
130static int __init v6_userpage_init(void)
131{
132 if (cache_is_vipt_aliasing()) {
Russell King303c6442008-10-31 16:32:19 +0000133 cpu_user.cpu_clear_user_highpage = v6_clear_user_highpage_aliasing;
Russell King063b0a42008-10-31 15:08:35 +0000134 cpu_user.cpu_copy_user_highpage = v6_copy_user_highpage_aliasing;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 }
136
137 return 0;
138}
139
Russell King08ee4e42005-05-10 17:30:47 +0100140core_initcall(v6_userpage_init);