4 #include <linux/spinlock.h>
7 #define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
8 #define SWAP_FLAG_PRIO_MASK 0x7fff
9 #define SWAP_FLAG_PRIO_SHIFT 0
11 #define MAX_SWAPFILES 8
16 char reserved
[PAGE_SIZE
- 10];
21 char bootbits
[1024]; /* Space for disklabel etc. */
23 unsigned int last_page
;
24 unsigned int nr_badpages
;
25 unsigned int padding
[125];
26 unsigned int badpages
[1];
33 * Max bad pages in the new format..
35 #define __swapoffset(x) ((unsigned long)&((union swap_header *)0)->x)
36 #define MAX_SWAP_BADPAGES \
37 ((__swapoffset(magic.magic) - __swapoffset(info.badpages)) / sizeof(int))
39 #include <asm/atomic.h>
44 #define SWAP_CLUSTER_MAX 32
46 #define SWAP_MAP_MAX 0x7fff
47 #define SWAP_MAP_BAD 0x8000
49 struct swap_info_struct
{
53 struct dentry
* swap_file
;
54 struct vfsmount
*swap_vfsmnt
;
55 unsigned short * swap_map
;
56 unsigned int lowest_bit
;
57 unsigned int highest_bit
;
58 unsigned int cluster_next
;
59 unsigned int cluster_nr
;
60 int prio
; /* swap priority */
63 int next
; /* next entry on swap list */
66 extern int nr_swap_pages
;
67 FASTCALL(unsigned int nr_free_pages(void));
68 FASTCALL(unsigned int nr_free_buffer_pages(void));
69 FASTCALL(unsigned int nr_free_highpages(void));
70 extern int nr_lru_pages
;
71 extern atomic_t nr_async_pages
;
72 extern struct address_space swapper_space
;
73 extern atomic_t page_cache_size
;
74 extern atomic_t buffermem_pages
;
76 /* Incomplete types for prototype declarations: */
78 struct vm_area_struct
;
83 extern int shm_swap(int, int);
86 extern void swap_setup(void);
88 /* linux/mm/vmscan.c */
89 extern int try_to_free_pages(unsigned int gfp_mask
);
91 /* linux/mm/page_io.c */
92 extern void rw_swap_page(int, struct page
*, int);
93 extern void rw_swap_page_nolock(int, swp_entry_t
, char *, int);
95 /* linux/mm/page_alloc.c */
97 /* linux/mm/swap_state.c */
98 extern void show_swap_cache_info(void);
99 extern void add_to_swap_cache(struct page
*, swp_entry_t
);
100 extern int swap_check_entry(unsigned long);
101 extern struct page
* lookup_swap_cache(swp_entry_t
);
102 extern struct page
* read_swap_cache_async(swp_entry_t
, int);
103 #define read_swap_cache(entry) read_swap_cache_async(entry, 1);
106 * Make these inline later once they are working properly.
108 extern void __delete_from_swap_cache(struct page
*page
);
109 extern void delete_from_swap_cache(struct page
*page
);
110 extern void delete_from_swap_cache_nolock(struct page
*page
);
111 extern void free_page_and_swap_cache(struct page
*page
);
113 /* linux/mm/swapfile.c */
114 extern unsigned int nr_swapfiles
;
115 extern struct swap_info_struct swap_info
[];
116 extern int is_swap_partition(kdev_t
);
117 extern void si_swapinfo(struct sysinfo
*);
118 extern swp_entry_t
__get_swap_page(unsigned short);
119 extern void get_swaphandle_info(swp_entry_t
, unsigned long *, kdev_t
*,
121 extern int swap_duplicate(swp_entry_t
);
122 extern int swap_count(struct page
*);
123 extern int valid_swaphandles(swp_entry_t
, unsigned long *);
124 #define get_swap_page() __get_swap_page(1)
125 extern void __swap_free(swp_entry_t
, unsigned short);
126 #define swap_free(entry) __swap_free((entry), 1)
128 int head
; /* head of priority-ordered swapfile list */
129 int next
; /* swapfile to be used next */
131 extern struct swap_list_t swap_list
;
132 asmlinkage
long sys_swapoff(const char *);
133 asmlinkage
long sys_swapon(const char *, int);
135 #define SWAP_CACHE_INFO
137 #ifdef SWAP_CACHE_INFO
138 extern unsigned long swap_cache_add_total
;
139 extern unsigned long swap_cache_del_total
;
140 extern unsigned long swap_cache_find_total
;
141 extern unsigned long swap_cache_find_success
;
145 * Work out if there are any other processes sharing this page, ignoring
146 * any page reference coming from the swap cache, or from outstanding
147 * swap IO on this page. (The page cache _does_ count as another valid
148 * reference to the page, however.)
150 static inline int is_page_shared(struct page
*page
)
153 if (PageReserved(page
))
155 count
= page_count(page
);
156 if (PageSwapCache(page
))
157 count
+= swap_count(page
) - 2 - !!page
->buffers
;
161 extern spinlock_t pagemap_lru_lock
;
164 * Helper macros for lru_pages handling.
166 #define lru_cache_add(page) \
168 spin_lock(&pagemap_lru_lock); \
169 list_add(&(page)->lru, &lru_cache); \
171 spin_unlock(&pagemap_lru_lock); \
174 #define __lru_cache_del(page) \
176 list_del(&(page)->lru); \
180 #define lru_cache_del(page) \
182 if (!PageLocked(page)) \
184 spin_lock(&pagemap_lru_lock); \
185 __lru_cache_del(page); \
186 spin_unlock(&pagemap_lru_lock); \
189 extern spinlock_t swaplock
;
191 #define swap_list_lock() spin_lock(&swaplock)
192 #define swap_list_unlock() spin_unlock(&swaplock)
193 #define swap_device_lock(p) spin_lock(&p->sdev_lock)
194 #define swap_device_unlock(p) spin_unlock(&p->sdev_lock)
196 #endif /* __KERNEL__*/
198 #endif /* _LINUX_SWAP_H */