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#ifndef _LINUX_SWAP_H
#define _LINUX_SWAP_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))
#undef DEBUG_SWAP
#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;
struct dentry * swap_file;
unsigned short * swap_map;
unsigned char * swap_lockmap;
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;
extern int nr_free_pages;
extern atomic_t nr_async_pages;
extern struct inode swapper_inode;
extern unsigned long page_cache_size;
extern long buffermem;
/* Incomplete types for prototype declarations: */
struct task_struct;
struct vm_area_struct;
struct sysinfo;
/* linux/ipc/shm.c */
extern int shm_swap (int, int);
/* linux/mm/swap.c */
extern void swap_setup (void);
/* linux/mm/vmscan.c */
extern int try_to_free_pages(unsigned int gfp_mask);
/* linux/mm/page_io.c */
extern void rw_swap_page(int, unsigned long, char *, int);
extern void rw_swap_page_nocache(int, unsigned long, char *);
extern void rw_swap_page_nolock(int, unsigned long, char *, int);
extern void swap_after_unlock_page (unsigned long entry);
/* linux/mm/page_alloc.c */
extern int swap_in(struct task_struct *, struct vm_area_struct *,
pte_t *, unsigned long, int);
/* linux/mm/swap_state.c */
extern void show_swap_cache_info(void);
extern int add_to_swap_cache(struct page *, unsigned long);
extern int swap_duplicate(unsigned long);
extern int swap_check_entry(unsigned long);
struct page * lookup_swap_cache(unsigned long);
extern struct page * read_swap_cache_async(unsigned long, int);
#define read_swap_cache(entry) read_swap_cache_async(entry, 1);
extern int FASTCALL(swap_count(unsigned long));
/*
* Make these inline later once they are working properly.
*/
extern void delete_from_swap_cache(struct page *page);
extern void free_page_and_swap_cache(unsigned long addr);
/* linux/mm/swapfile.c */
extern unsigned int nr_swapfiles;
extern struct swap_info_struct swap_info[];
void si_swapinfo(struct sysinfo *);
unsigned long get_swap_page(void);
extern void FASTCALL(swap_free(unsigned long));
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 int sys_swapoff(const char *);
asmlinkage int sys_swapon(const char *, int);
/*
* vm_ops not present page codes for shared memory.
*
* Will go away eventually..
*/
#define SHM_SWP_TYPE 0x20
/*
* swap cache stuff (in linux/mm/swap_state.c)
*/
#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
extern inline unsigned long in_swap_cache(struct page *page)
{
if (PageSwapCache(page))
return page->offset;
return 0;
}
/*
* 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 = atomic_read(&page->count);
if (PageSwapCache(page))
count += swap_count(page->offset) - 2;
if (PageFreeAfter(page))
count--;
return count > 1;
}
#endif /* __KERNEL__*/
#endif /* _LINUX_SWAP_H */
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