1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
|
#ifndef _LINUX_HIGHMEM_H
#define _LINUX_HIGHMEM_H
#include <linux/config.h>
#include <asm/pgalloc.h>
#ifdef CONFIG_HIGHMEM
extern struct page *highmem_start_page;
#include <asm/highmem.h>
/* declarations for linux/mm/highmem.c */
FASTCALL(unsigned int nr_free_highpages(void));
extern struct page * prepare_highmem_swapout(struct page *);
extern struct page * replace_with_highmem(struct page *);
extern struct buffer_head * create_bounce(int rw, struct buffer_head * bh_orig);
#else /* CONFIG_HIGHMEM */
static inline unsigned int nr_free_highpages(void) { return 0; }
#define prepare_highmem_swapout(page) page
#define replace_with_highmem(page) page
static __inline__ unsigned long kmap(struct page * page) {
return (unsigned long) page_address(page);
}
#define kunmap(page) do { } while (0)
#define kmap_atomic(page,idx) kmap(page)
#define kunmap_atomic(page,idx) kunmap(page)
#endif /* CONFIG_HIGHMEM */
/* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
{
unsigned long kaddr;
kaddr = kmap(page);
clear_user_page((void *)kaddr, vaddr);
kunmap(page);
}
static inline void clear_highpage(struct page *page)
{
unsigned long kaddr;
kaddr = kmap(page);
clear_page((void *)kaddr);
kunmap(page);
}
static inline void memclear_highpage(struct page *page, unsigned int offset, unsigned int size)
{
unsigned long kaddr;
if (offset + size > PAGE_SIZE)
BUG();
kaddr = kmap(page);
memset((void *)(kaddr + offset), 0, size);
kunmap(page);
}
/*
* Same but also flushes aliased cache contents to RAM.
*/
static inline void memclear_highpage_flush(struct page *page, unsigned int offset, unsigned int size)
{
unsigned long kaddr;
if (offset + size > PAGE_SIZE)
BUG();
kaddr = kmap(page);
memset((void *)(kaddr + offset), 0, size);
flush_page_to_ram(page);
kunmap(page);
}
static inline void copy_user_highpage(struct page *to, struct page *from, unsigned long vaddr)
{
unsigned long vfrom, vto;
vfrom = kmap(from);
vto = kmap(to);
copy_user_page((void *)vto, (void *)vfrom, vaddr);
kunmap(from);
kunmap(to);
}
static inline void copy_highpage(struct page *to, struct page *from)
{
unsigned long vfrom, vto;
vfrom = kmap(from);
vto = kmap(to);
copy_page((void *)vto, (void *)vfrom);
kunmap(from);
kunmap(to);
}
#endif /* _LINUX_HIGHMEM_H */
|
