Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1#ifndef _LINUX_FRONTSWAP_H
2#define _LINUX_FRONTSWAP_H
3
4#include <linux/swap.h>
5#include <linux/mm.h>
6#include <linux/bitops.h>
7
8struct frontswap_ops {
9 void (*init)(unsigned);
10 int (*store)(unsigned, pgoff_t, struct page *);
11 int (*load)(unsigned, pgoff_t, struct page *);
12 void (*invalidate_page)(unsigned, pgoff_t);
13 void (*invalidate_area)(unsigned);
14};
15
16extern bool frontswap_enabled;
17extern struct frontswap_ops
18 frontswap_register_ops(struct frontswap_ops *ops);
19extern void frontswap_shrink(unsigned long);
20extern unsigned long frontswap_curr_pages(void);
21extern void frontswap_writethrough(bool);
22#define FRONTSWAP_HAS_EXCLUSIVE_GETS
23extern void frontswap_tmem_exclusive_gets(bool);
24
25extern void __frontswap_init(unsigned type);
26extern int __frontswap_store(struct page *page);
27extern int __frontswap_load(struct page *page);
28extern void __frontswap_invalidate_page(unsigned, pgoff_t);
29extern void __frontswap_invalidate_area(unsigned);
30
31#ifdef CONFIG_FRONTSWAP
32
33static inline bool frontswap_test(struct swap_info_struct *sis, pgoff_t offset)
34{
35 bool ret = false;
36
37 if (frontswap_enabled && sis->frontswap_map)
38 ret = test_bit(offset, sis->frontswap_map);
39 return ret;
40}
41
42static inline void frontswap_set(struct swap_info_struct *sis, pgoff_t offset)
43{
44 if (frontswap_enabled && sis->frontswap_map)
45 set_bit(offset, sis->frontswap_map);
46}
47
48static inline void frontswap_clear(struct swap_info_struct *sis, pgoff_t offset)
49{
50 if (frontswap_enabled && sis->frontswap_map)
51 clear_bit(offset, sis->frontswap_map);
52}
53
54static inline void frontswap_map_set(struct swap_info_struct *p,
55 unsigned long *map)
56{
57 p->frontswap_map = map;
58}
59
60static inline unsigned long *frontswap_map_get(struct swap_info_struct *p)
61{
62 return p->frontswap_map;
63}
64#else
65/* all inline routines become no-ops and all externs are ignored */
66
67#define frontswap_enabled (0)
68
69static inline bool frontswap_test(struct swap_info_struct *sis, pgoff_t offset)
70{
71 return false;
72}
73
74static inline void frontswap_set(struct swap_info_struct *sis, pgoff_t offset)
75{
76}
77
78static inline void frontswap_clear(struct swap_info_struct *sis, pgoff_t offset)
79{
80}
81
82static inline void frontswap_map_set(struct swap_info_struct *p,
83 unsigned long *map)
84{
85}
86
87static inline unsigned long *frontswap_map_get(struct swap_info_struct *p)
88{
89 return NULL;
90}
91#endif
92
93static inline int frontswap_store(struct page *page)
94{
95 int ret = -1;
96
97 if (frontswap_enabled)
98 ret = __frontswap_store(page);
99 return ret;
100}
101
102static inline int frontswap_load(struct page *page)
103{
104 int ret = -1;
105
106 if (frontswap_enabled)
107 ret = __frontswap_load(page);
108 return ret;
109}
110
111static inline void frontswap_invalidate_page(unsigned type, pgoff_t offset)
112{
113 if (frontswap_enabled)
114 __frontswap_invalidate_page(type, offset);
115}
116
117static inline void frontswap_invalidate_area(unsigned type)
118{
119 if (frontswap_enabled)
120 __frontswap_invalidate_area(type);
121}
122
123static inline void frontswap_init(unsigned type)
124{
125 if (frontswap_enabled)
126 __frontswap_init(type);
127}
128
129#endif /* _LINUX_FRONTSWAP_H */