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
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
|
#ifndef _LINUX_SWAP_H
#define _LINUX_SWAP_H
#include <linux/spinlock.h>
#include <asm/page.h>
#define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
#define SWAP_FLAG_PRIO_MASK 0x7fff
#define SWAP_FLAG_PRIO_SHIFT 0
#define MAX_SWAPFILES 8
union swap_header {
struct
{
char reserved[PAGE_SIZE - 10];
char magic[10];
} magic;
struct
{
char bootbits[1024]; /* Space for disklabel etc. */
unsigned int version;
unsigned int last_page;
unsigned int nr_badpages;
unsigned int padding[125];
unsigned int badpages[1];
} info;
};
#ifdef __KERNEL__
/*
* Max bad pages in the new format..
*/
#define __swapoffset(x) ((unsigned long)&((union swap_header *)0)->x)
#define MAX_SWAP_BADPAGES \
((__swapoffset(magic.magic) - __swapoffset(info.badpages)) / sizeof(int))
#include <asm/atomic.h>
#define SWP_USED 1
#define SWP_WRITEOK 3
#define SWAP_CLUSTER_MAX 32
#define SWAP_MAP_MAX 0x7fff
#define SWAP_MAP_BAD 0x8000
struct swap_info_struct {
unsigned int flags;
kdev_t swap_device;
spinlock_t sdev_lock;
struct dentry * swap_file;
unsigned short * swap_map;
unsigned int lowest_bit;
unsigned int highest_bit;
unsigned int cluster_next;
unsigned int cluster_nr;
int prio; /* swap priority */
int pages;
unsigned long max;
int next; /* next entry on swap list */
};
extern int nr_swap_pages;
FASTCALL(unsigned int nr_free_pages(void));
FASTCALL(unsigned int nr_free_buffer_pages(void));
FASTCALL(unsigned int nr_free_highpages(void));
extern int nr_lru_pages;
extern atomic_t nr_async_pages;
extern struct address_space swapper_space;
extern atomic_t page_cache_size;
extern atomic_t buffermem_pages;
/* Incomplete types for prototype declarations: */
struct task_struct;
struct vm_area_struct;
struct sysinfo;
struct zone_t;
/* linux/ipc/shm.c */
extern int shm_swap (int, int, zone_t *);
/* linux/mm/swap.c */
extern void swap_setup (void);
/* linux/mm/vmscan.c */
extern int try_to_free_pages(unsigned int gfp_mask, zone_t *zone);
/* linux/mm/page_io.c */
extern void rw_swap_page(int, struct page *, int);
extern void rw_swap_page_nolock(int, swp_entry_t, char *, int);
/* linux/mm/page_alloc.c */
/* linux/mm/swap_state.c */
extern void show_swap_cache_info(void);
extern void add_to_swap_cache(struct page *, swp_entry_t);
extern int swap_check_entry(unsigned long);
extern struct page * lookup_swap_cache(swp_entry_t);
extern struct page * read_swap_cache_async(swp_entry_t, int);
#define read_swap_cache(entry) read_swap_cache_async(entry, 1);
/*
* Make these inline later once they are working properly.
*/
extern void __delete_from_swap_cache(struct page *page);
extern void delete_from_swap_cache(struct page *page);
extern void delete_from_swap_cache_nolock(struct page *page);
extern void free_page_and_swap_cache(struct page *page);
/* linux/mm/swapfile.c */
extern unsigned int nr_swapfiles;
extern struct swap_info_struct swap_info[];
extern int is_swap_partition(kdev_t);
extern void si_swapinfo(struct sysinfo *);
extern swp_entry_t __get_swap_page(unsigned short);
extern void get_swaphandle_info(swp_entry_t, unsigned long *, kdev_t *,
struct inode **);
extern int swap_duplicate(swp_entry_t);
extern int swap_count(struct page *);
extern swp_entry_t acquire_swap_entry(struct page *page);
extern int valid_swaphandles(swp_entry_t, unsigned long *);
#define get_swap_page() __get_swap_page(1)
extern void __swap_free(swp_entry_t, unsigned short);
#define swap_free(entry) __swap_free((entry), 1)
struct swap_list_t {
int head; /* head of priority-ordered swapfile list */
int next; /* swapfile to be used next */
};
extern struct swap_list_t swap_list;
asmlinkage long sys_swapoff(const char *);
asmlinkage long sys_swapon(const char *, int);
#define SWAP_CACHE_INFO
#ifdef SWAP_CACHE_INFO
extern unsigned long swap_cache_add_total;
extern unsigned long swap_cache_del_total;
extern unsigned long swap_cache_find_total;
extern unsigned long swap_cache_find_success;
#endif
/*
* Work out if there are any other processes sharing this page, ignoring
* any page reference coming from the swap cache, or from outstanding
* swap IO on this page. (The page cache _does_ count as another valid
* reference to the page, however.)
*/
static inline int is_page_shared(struct page *page)
{
unsigned int count;
if (PageReserved(page))
return 1;
count = page_count(page);
if (PageSwapCache(page))
count += swap_count(page) - 2;
return count > 1;
}
extern spinlock_t pagemap_lru_lock;
/*
* Helper macros for lru_pages handling.
*/
#define lru_cache_add(page) \
do { \
spin_lock(&pagemap_lru_lock); \
list_add(&(page)->lru, &page->zone->lru_cache); \
nr_lru_pages++; \
spin_unlock(&pagemap_lru_lock); \
} while (0)
#define lru_cache_del(page) \
do { \
spin_lock(&pagemap_lru_lock); \
list_del(&(page)->lru); \
nr_lru_pages--; \
spin_unlock(&pagemap_lru_lock); \
} while (0)
extern spinlock_t swaplock;
#define swap_list_lock() spin_lock(&swaplock)
#define swap_list_unlock() spin_unlock(&swaplock)
#define swap_device_lock(p) spin_lock(&p->sdev_lock)
#define swap_device_unlock(p) spin_unlock(&p->sdev_lock)
#endif /* __KERNEL__*/
#endif /* _LINUX_SWAP_H */
|