1/*
2 * linux/arch/unicore32/mm/flush.c
3 *
4 * Code specific to PKUnity SoC and UniCore ISA
5 *
6 * Copyright (C) 2001-2010 GUAN Xue-tao
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12#include <linux/module.h>
13#include <linux/mm.h>
14#include <linux/pagemap.h>
15
16#include <asm/cacheflush.h>
17#include <asm/tlbflush.h>
18
19void flush_cache_mm(struct mm_struct *mm)
20{
21}
22
23void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
24		unsigned long end)
25{
26	if (vma->vm_flags & VM_EXEC)
27		__flush_icache_all();
28}
29
30void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr,
31		unsigned long pfn)
32{
33}
34
35static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
36			 unsigned long uaddr, void *kaddr, unsigned long len)
37{
38	/* VIPT non-aliasing D-cache */
39	if (vma->vm_flags & VM_EXEC) {
40		unsigned long addr = (unsigned long)kaddr;
41
42		__cpuc_coherent_kern_range(addr, addr + len);
43	}
44}
45
46/*
47 * Copy user data from/to a page which is mapped into a different
48 * processes address space.  Really, we want to allow our "user
49 * space" model to handle this.
50 *
51 * Note that this code needs to run on the current CPU.
52 */
53void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
54		       unsigned long uaddr, void *dst, const void *src,
55		       unsigned long len)
56{
57	memcpy(dst, src, len);
58	flush_ptrace_access(vma, page, uaddr, dst, len);
59}
60
61void __flush_dcache_page(struct address_space *mapping, struct page *page)
62{
63	/*
64	 * Writeback any data associated with the kernel mapping of this
65	 * page.  This ensures that data in the physical page is mutually
66	 * coherent with the kernels mapping.
67	 */
68	__cpuc_flush_kern_dcache_area(page_address(page), PAGE_SIZE);
69}
70
71/*
72 * Ensure cache coherency between kernel mapping and userspace mapping
73 * of this page.
74 */
75void flush_dcache_page(struct page *page)
76{
77	struct address_space *mapping;
78
79	/*
80	 * The zero page is never written to, so never has any dirty
81	 * cache lines, and therefore never needs to be flushed.
82	 */
83	if (page == ZERO_PAGE(0))
84		return;
85
86	mapping = page_mapping(page);
87
88	if (mapping && !mapping_mapped(mapping))
89		clear_bit(PG_dcache_clean, &page->flags);
90	else {
91		__flush_dcache_page(mapping, page);
92		if (mapping)
93			__flush_icache_all();
94		set_bit(PG_dcache_clean, &page->flags);
95	}
96}
97EXPORT_SYMBOL(flush_dcache_page);
98