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 
flush_cache_mm(struct mm_struct * mm)19 void flush_cache_mm(struct mm_struct *mm)
20 {
21 }
22 
flush_cache_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)23 void 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 
flush_cache_page(struct vm_area_struct * vma,unsigned long user_addr,unsigned long pfn)30 void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr,
31 		unsigned long pfn)
32 {
33 }
34 
flush_ptrace_access(struct vm_area_struct * vma,struct page * page,unsigned long uaddr,void * kaddr,unsigned long len)35 static 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  */
copy_to_user_page(struct vm_area_struct * vma,struct page * page,unsigned long uaddr,void * dst,const void * src,unsigned long len)53 void 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 
__flush_dcache_page(struct address_space * mapping,struct page * page)61 void __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  */
flush_dcache_page(struct page * page)75 void 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_file(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 }
97 EXPORT_SYMBOL(flush_dcache_page);
98