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gerrit-public.fairphone.software / kernel / msm-4.9 / 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 / . / arch / sh / mm / pg-sh4.c
blob: e5907c7330e5c44a85946e4a642cb67f2ddfebd3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame^]1/*
2 * arch/sh/mm/pg-sh4.c
3 *
4 * Copyright (C) 1999, 2000, 2002 Niibe Yutaka
5 * Copyright (C) 2002 Paul Mundt
6 *
7 * Released under the terms of the GNU GPL v2.0.
8 */
9#include <linux/config.h>
10#include <linux/init.h>
11#include <linux/mman.h>
12#include <linux/mm.h>
13#include <linux/threads.h>
14#include <asm/addrspace.h>
15#include <asm/page.h>
16#include <asm/pgtable.h>
17#include <asm/processor.h>
18#include <asm/cache.h>
19#include <asm/io.h>
20#include <asm/uaccess.h>
21#include <asm/pgalloc.h>
22#include <asm/mmu_context.h>
23#include <asm/cacheflush.h>
24
25extern struct semaphore p3map_sem[];
26
27/*
28 * clear_user_page
29 * @to: P1 address
30 * @address: U0 address to be mapped
31 * @page: page (virt_to_page(to))
32 */
33void clear_user_page(void *to, unsigned long address, struct page *page)
34{
35 __set_bit(PG_mapped, &page->flags);
36 if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
37 clear_page(to);
38 else {
39 pgprot_t pgprot = __pgprot(_PAGE_PRESENT |
40 _PAGE_RW | _PAGE_CACHABLE |
41 _PAGE_DIRTY | _PAGE_ACCESSED |
42 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD);
43 unsigned long phys_addr = PHYSADDR(to);
44 unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
45 pgd_t *dir = pgd_offset_k(p3_addr);
46 pmd_t *pmd = pmd_offset(dir, p3_addr);
47 pte_t *pte = pte_offset_kernel(pmd, p3_addr);
48 pte_t entry;
49 unsigned long flags;
50
51 entry = pfn_pte(phys_addr >> PAGE_SHIFT, pgprot);
52 down(&p3map_sem[(address & CACHE_ALIAS)>>12]);
53 set_pte(pte, entry);
54 local_irq_save(flags);
55 __flush_tlb_page(get_asid(), p3_addr);
56 local_irq_restore(flags);
57 update_mmu_cache(NULL, p3_addr, entry);
58 __clear_user_page((void *)p3_addr, to);
59 pte_clear(&init_mm, p3_addr, pte);
60 up(&p3map_sem[(address & CACHE_ALIAS)>>12]);
61 }
62}
63
64/*
65 * copy_user_page
66 * @to: P1 address
67 * @from: P1 address
68 * @address: U0 address to be mapped
69 * @page: page (virt_to_page(to))
70 */
71void copy_user_page(void *to, void *from, unsigned long address,
72 struct page *page)
73{
74 __set_bit(PG_mapped, &page->flags);
75 if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
76 copy_page(to, from);
77 else {
78 pgprot_t pgprot = __pgprot(_PAGE_PRESENT |
79 _PAGE_RW | _PAGE_CACHABLE |
80 _PAGE_DIRTY | _PAGE_ACCESSED |
81 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD);
82 unsigned long phys_addr = PHYSADDR(to);
83 unsigned long p3_addr = P3SEG + (address & CACHE_ALIAS);
84 pgd_t *dir = pgd_offset_k(p3_addr);
85 pmd_t *pmd = pmd_offset(dir, p3_addr);
86 pte_t *pte = pte_offset_kernel(pmd, p3_addr);
87 pte_t entry;
88 unsigned long flags;
89
90 entry = pfn_pte(phys_addr >> PAGE_SHIFT, pgprot);
91 down(&p3map_sem[(address & CACHE_ALIAS)>>12]);
92 set_pte(pte, entry);
93 local_irq_save(flags);
94 __flush_tlb_page(get_asid(), p3_addr);
95 local_irq_restore(flags);
96 update_mmu_cache(NULL, p3_addr, entry);
97 __copy_user_page((void *)p3_addr, from, to);
98 pte_clear(&init_mm, p3_addr, pte);
99 up(&p3map_sem[(address & CACHE_ALIAS)>>12]);
100 }
101}
102
103/*
104 * For SH-4, we have our own implementation for ptep_get_and_clear
105 */
106inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
107{
108 pte_t pte = *ptep;
109
110 pte_clear(mm, addr, ptep);
111 if (!pte_not_present(pte)) {
112 unsigned long pfn = pte_pfn(pte);
113 if (pfn_valid(pfn)) {
114 struct page *page = pfn_to_page(pfn);
115 struct address_space *mapping = page_mapping(page);
116 if (!mapping || !mapping_writably_mapped(mapping))
117 __clear_bit(PG_mapped, &page->flags);
118 }
119 }
120 return pte;
121}
122