4 * Copyright (C) 1999, 2000, 2002 Niibe Yutaka
5 * Copyright (C) 2002 - 2007 Paul Mundt
7 * Released under the terms of the GNU GPL v2.0.
10 #include <linux/mutex.h>
12 #include <linux/highmem.h>
13 #include <linux/module.h>
14 #include <asm/mmu_context.h>
15 #include <asm/cacheflush.h>
17 #define CACHE_ALIAS (current_cpu_data.dcache.alias_mask)
19 static inline void *kmap_coherent(struct page *page, unsigned long addr)
21 enum fixed_addresses idx;
22 unsigned long vaddr, flags;
27 idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT;
28 vaddr = __fix_to_virt(FIX_CMAP_END - idx);
29 pte = mk_pte(page, PAGE_KERNEL);
31 local_irq_save(flags);
32 flush_tlb_one(get_asid(), vaddr);
33 local_irq_restore(flags);
35 update_mmu_cache(NULL, vaddr, pte);
40 static inline void kunmap_coherent(struct page *page)
43 preempt_check_resched();
49 * @address: U0 address to be mapped
50 * @page: page (virt_to_page(to))
52 void clear_user_page(void *to, unsigned long address, struct page *page)
54 __set_bit(PG_mapped, &page->flags);
55 if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
58 void *vto = kmap_coherent(page, address);
59 __clear_user_page(vto, to);
68 * @address: U0 address to be mapped
69 * @page: page (virt_to_page(to))
71 void copy_user_page(void *to, void *from, unsigned long address,
74 __set_bit(PG_mapped, &page->flags);
75 if (((address ^ (unsigned long)to) & CACHE_ALIAS) == 0)
78 void *vfrom = kmap_coherent(page, address);
79 __copy_user_page(vfrom, from, to);
80 kunmap_coherent(vfrom);
84 void copy_user_highpage(struct page *to, struct page *from,
85 unsigned long vaddr, struct vm_area_struct *vma)
89 __set_bit(PG_mapped, &to->flags);
91 vto = kmap_atomic(to, KM_USER1);
92 vfrom = kmap_coherent(from, vaddr);
93 copy_page(vto, vfrom);
94 kunmap_coherent(vfrom);
96 if (((vaddr ^ (unsigned long)vto) & CACHE_ALIAS))
97 __flush_wback_region(vto, PAGE_SIZE);
99 kunmap_atomic(vto, KM_USER1);
100 /* Make sure this page is cleared on other CPU's too before using it */
103 EXPORT_SYMBOL(copy_user_highpage);
106 * For SH-4, we have our own implementation for ptep_get_and_clear
108 inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
112 pte_clear(mm, addr, ptep);
113 if (!pte_not_present(pte)) {
114 unsigned long pfn = pte_pfn(pte);
115 if (pfn_valid(pfn)) {
116 struct page *page = pfn_to_page(pfn);
117 struct address_space *mapping = page_mapping(page);
118 if (!mapping || !mapping_writably_mapped(mapping))
119 __clear_bit(PG_mapped, &page->flags);