[deliverable/linux.git] / include / linux / swap.h

#ifndef _LINUX_SWAP_H
#define _LINUX_SWAP_H

#include <linux/spinlock.h>
#include <linux/linkage.h>
#include <linux/mmzone.h>
#include <linux/list.h>
#include <linux/sched.h>

#include <asm/atomic.h>
#include <asm/page.h>

struct notifier_block;

#define SWAP_FLAG_PREFER	0x8000	/* set if swap priority specified */
#define SWAP_FLAG_PRIO_MASK	0x7fff
#define SWAP_FLAG_PRIO_SHIFT	0

static inline int current_is_kswapd(void)
{
	return current->flags & PF_KSWAPD;
}

/*
 * MAX_SWAPFILES defines the maximum number of swaptypes: things which can
 * be swapped to.  The swap type and the offset into that swap type are
 * encoded into pte's and into pgoff_t's in the swapcache.  Using five bits
 * for the type means that the maximum number of swapcache pages is 27 bits
 * on 32-bit-pgoff_t architectures.  And that assumes that the architecture packs
 * the type/offset into the pte as 5/27 as well.
 */
#define MAX_SWAPFILES_SHIFT	5
#ifndef CONFIG_MIGRATION
#define MAX_SWAPFILES		(1 << MAX_SWAPFILES_SHIFT)
#else
/* Use last two entries for page migration swap entries */
#define MAX_SWAPFILES		((1 << MAX_SWAPFILES_SHIFT)-2)
#define SWP_MIGRATION_READ	MAX_SWAPFILES
#define SWP_MIGRATION_WRITE	(MAX_SWAPFILES + 1)
#endif

/*
 * Magic header for a swap area. The first part of the union is
 * what the swap magic looks like for the old (limited to 128MB)
 * swap area format, the second part of the union adds - in the
 * old reserved area - some extra information. Note that the first
 * kilobyte is reserved for boot loader or disk label stuff...
 *
 * Having the magic at the end of the PAGE_SIZE makes detecting swap
 * areas somewhat tricky on machines that support multiple page sizes.
 * For 2.5 we'll probably want to move the magic to just beyond the
 * bootbits...
 */
union swap_header {
	struct {
		char reserved[PAGE_SIZE - 10];
		char magic[10];			/* SWAP-SPACE or SWAPSPACE2 */
	} magic;
	struct {
		char		bootbits[1024];	/* Space for disklabel etc. */
		__u32		version;
		__u32		last_page;
		__u32		nr_badpages;
		unsigned char	sws_uuid[16];
		unsigned char	sws_volume[16];
		__u32		padding[117];
		__u32		badpages[1];
	} info;
};

 /* A swap entry has to fit into a "unsigned long", as
  * the entry is hidden in the "index" field of the
  * swapper address space.
  */
typedef struct {
	unsigned long val;
} swp_entry_t;

/*
 * current->reclaim_state points to one of these when a task is running
 * memory reclaim
 */
struct reclaim_state {
	unsigned long reclaimed_slab;
};

#ifdef __KERNEL__

struct address_space;
struct sysinfo;
struct writeback_control;
struct zone;

/*
 * A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of
 * disk blocks.  A list of swap extents maps the entire swapfile.  (Where the
 * term `swapfile' refers to either a blockdevice or an IS_REG file.  Apart
 * from setup, they're handled identically.
 *
 * We always assume that blocks are of size PAGE_SIZE.
 */
struct swap_extent {
	struct list_head list;
	pgoff_t start_page;
	pgoff_t nr_pages;
	sector_t start_block;
};

/*
 * 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))

enum {
	SWP_USED	= (1 << 0),	/* is slot in swap_info[] used? */
	SWP_WRITEOK	= (1 << 1),	/* ok to write to this swap?	*/
	SWP_ACTIVE	= (SWP_USED | SWP_WRITEOK),
					/* add others here before... */
	SWP_SCANNING	= (1 << 8),	/* refcount in scan_swap_map */
};

#define SWAP_CLUSTER_MAX 32

#define SWAP_MAP_MAX	0x7fff
#define SWAP_MAP_BAD	0x8000

/*
 * The in-memory structure used to track swap areas.
 */
struct swap_info_struct {
	unsigned int flags;
	int prio;			/* swap priority */
	struct file *swap_file;
	struct block_device *bdev;
	struct list_head extent_list;
	struct swap_extent *curr_swap_extent;
	unsigned old_block_size;
	unsigned short * swap_map;
	unsigned int lowest_bit;
	unsigned int highest_bit;
	unsigned int cluster_next;
	unsigned int cluster_nr;
	unsigned int pages;
	unsigned int max;
	unsigned int inuse_pages;
	int next;			/* next entry on swap list */
};

struct swap_list_t {
	int head;	/* head of priority-ordered swapfile list */
	int next;	/* swapfile to be used next */
};

/* Swap 50% full? Release swapcache more aggressively.. */
#define vm_swap_full() (nr_swap_pages*2 < total_swap_pages)

/* linux/mm/oom_kill.c */
extern void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order);
extern int register_oom_notifier(struct notifier_block *nb);
extern int unregister_oom_notifier(struct notifier_block *nb);

/* linux/mm/memory.c */
extern void swapin_readahead(swp_entry_t, unsigned long, struct vm_area_struct *);

/* linux/mm/page_alloc.c */
extern unsigned long totalram_pages;
extern unsigned long totalreserve_pages;
extern long nr_swap_pages;
extern unsigned int nr_free_pages(void);
extern unsigned int nr_free_pages_pgdat(pg_data_t *pgdat);
extern unsigned int nr_free_buffer_pages(void);
extern unsigned int nr_free_pagecache_pages(void);

/* linux/mm/swap.c */
extern void FASTCALL(lru_cache_add(struct page *));
extern void FASTCALL(lru_cache_add_active(struct page *));
extern void FASTCALL(activate_page(struct page *));
extern void FASTCALL(mark_page_accessed(struct page *));
extern void lru_add_drain(void);
extern int lru_add_drain_all(void);
extern int rotate_reclaimable_page(struct page *page);
extern void swap_setup(void);

/* linux/mm/vmscan.c */
extern unsigned long try_to_free_pages(struct zone **, gfp_t);
extern unsigned long shrink_all_memory(unsigned long nr_pages);
extern int vm_swappiness;
extern int remove_mapping(struct address_space *mapping, struct page *page);
extern long vm_total_pages;

#ifdef CONFIG_NUMA
extern int zone_reclaim_mode;
extern int sysctl_min_unmapped_ratio;
extern int sysctl_min_slab_ratio;
extern int zone_reclaim(struct zone *, gfp_t, unsigned int);
#else
#define zone_reclaim_mode 0
static inline int zone_reclaim(struct zone *z, gfp_t mask, unsigned int order)
{
	return 0;
}
#endif

extern int kswapd_run(int nid);

#ifdef CONFIG_MMU
/* linux/mm/shmem.c */
extern int shmem_unuse(swp_entry_t entry, struct page *page);
#endif /* CONFIG_MMU */

extern void swap_unplug_io_fn(struct backing_dev_info *, struct page *);

#ifdef CONFIG_SWAP
/* linux/mm/page_io.c */
extern int swap_readpage(struct file *, struct page *);
extern int swap_writepage(struct page *page, struct writeback_control *wbc);
extern int rw_swap_page_sync(int, swp_entry_t, struct page *);

/* linux/mm/swap_state.c */
extern struct address_space swapper_space;
#define total_swapcache_pages  swapper_space.nrpages
extern void show_swap_cache_info(void);
extern int add_to_swap(struct page *, gfp_t);
extern void __delete_from_swap_cache(struct page *);
extern void delete_from_swap_cache(struct page *);
extern int move_to_swap_cache(struct page *, swp_entry_t);
extern int move_from_swap_cache(struct page *, unsigned long,
		struct address_space *);
extern void free_page_and_swap_cache(struct page *);
extern void free_pages_and_swap_cache(struct page **, int);
extern struct page * lookup_swap_cache(swp_entry_t);
extern struct page * read_swap_cache_async(swp_entry_t, struct vm_area_struct *vma,
					   unsigned long addr);
/* linux/mm/swapfile.c */
extern long total_swap_pages;
extern unsigned int nr_swapfiles;
extern void si_swapinfo(struct sysinfo *);
extern swp_entry_t get_swap_page(void);
extern swp_entry_t get_swap_page_of_type(int);
extern int swap_duplicate(swp_entry_t);
extern int valid_swaphandles(swp_entry_t, unsigned long *);
extern void swap_free(swp_entry_t);
extern void free_swap_and_cache(swp_entry_t);
extern int swap_type_of(dev_t);
extern unsigned int count_swap_pages(int, int);
extern sector_t map_swap_page(struct swap_info_struct *, pgoff_t);
extern struct swap_info_struct *get_swap_info_struct(unsigned);
extern int can_share_swap_page(struct page *);
extern int remove_exclusive_swap_page(struct page *);
struct backing_dev_info;

extern spinlock_t swap_lock;

/* linux/mm/thrash.c */
extern struct mm_struct * swap_token_mm;
extern unsigned long swap_token_default_timeout;
extern void grab_swap_token(void);
extern void __put_swap_token(struct mm_struct *);

static inline int has_swap_token(struct mm_struct *mm)
{
	return (mm == swap_token_mm);
}

static inline void put_swap_token(struct mm_struct *mm)
{
	if (has_swap_token(mm))
		__put_swap_token(mm);
}

static inline void disable_swap_token(void)
{
	put_swap_token(swap_token_mm);
}

#else /* CONFIG_SWAP */

#define total_swap_pages			0
#define total_swapcache_pages			0UL

#define si_swapinfo(val) \
	do { (val)->freeswap = (val)->totalswap = 0; } while (0)
/* only sparc can not include linux/pagemap.h in this file
 * so leave page_cache_release and release_pages undeclared... */
#define free_page_and_swap_cache(page) \
	page_cache_release(page)
#define free_pages_and_swap_cache(pages, nr) \
	release_pages((pages), (nr), 0);

static inline void show_swap_cache_info(void)
{
}

static inline void free_swap_and_cache(swp_entry_t swp)
{
}

static inline int swap_duplicate(swp_entry_t swp)
{
	return 0;
}

static inline void swap_free(swp_entry_t swp)
{
}

static inline struct page *read_swap_cache_async(swp_entry_t swp,
			struct vm_area_struct *vma, unsigned long addr)
{
	return NULL;
}

static inline struct page *lookup_swap_cache(swp_entry_t swp)
{
	return NULL;
}

static inline int valid_swaphandles(swp_entry_t entry, unsigned long *offset)
{
	return 0;
}

#define can_share_swap_page(p)			(page_mapcount(p) == 1)

static inline int move_to_swap_cache(struct page *page, swp_entry_t entry)
{
	return 1;
}

static inline int move_from_swap_cache(struct page *page, unsigned long index,
					struct address_space *mapping)
{
	return 1;
}

static inline void __delete_from_swap_cache(struct page *page)
{
}

static inline void delete_from_swap_cache(struct page *page)
{
}

#define swap_token_default_timeout		0

static inline int remove_exclusive_swap_page(struct page *p)
{
	return 0;
}

static inline swp_entry_t get_swap_page(void)
{
	swp_entry_t entry;
	entry.val = 0;
	return entry;
}

/* linux/mm/thrash.c */
#define put_swap_token(x) do { } while(0)
#define grab_swap_token()  do { } while(0)
#define has_swap_token(x) 0
#define disable_swap_token() do { } while(0)

#endif /* CONFIG_SWAP */
#endif /* __KERNEL__*/
#endif /* _LINUX_SWAP_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_SWAP_H
	2	#define _LINUX_SWAP_H
	3
1da177e4 LT	4	#include <linux/spinlock.h>
	5	#include <linux/linkage.h>
	6	#include <linux/mmzone.h>
	7	#include <linux/list.h>
	8	#include <linux/sched.h>
542d1c88	9
1da177e4 LT	10	#include <asm/atomic.h>
	11	#include <asm/page.h>
	12
8bc719d3 MS	13	struct notifier_block;
8bc719d3 MS	14
1da177e4 LT	15	#define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
	16	#define SWAP_FLAG_PRIO_MASK 0x7fff
	17	#define SWAP_FLAG_PRIO_SHIFT 0
	18
	19	static inline int current_is_kswapd(void)
	20	{
	21	return current->flags & PF_KSWAPD;
	22	}
	23
	24	/*
	25	* MAX_SWAPFILES defines the maximum number of swaptypes: things which can
	26	* be swapped to. The swap type and the offset into that swap type are
	27	* encoded into pte's and into pgoff_t's in the swapcache. Using five bits
	28	* for the type means that the maximum number of swapcache pages is 27 bits
	29	* on 32-bit-pgoff_t architectures. And that assumes that the architecture packs
	30	* the type/offset into the pte as 5/27 as well.
	31	*/
	32	#define MAX_SWAPFILES_SHIFT 5
0697212a	33	#ifndef CONFIG_MIGRATION
1da177e4	34	#define MAX_SWAPFILES (1 << MAX_SWAPFILES_SHIFT)
0697212a CL	35	#else
	36	/* Use last two entries for page migration swap entries */
	37	#define MAX_SWAPFILES ((1 << MAX_SWAPFILES_SHIFT)-2)
	38	#define SWP_MIGRATION_READ MAX_SWAPFILES
	39	#define SWP_MIGRATION_WRITE (MAX_SWAPFILES + 1)
	40	#endif
1da177e4 LT	41
	42	/*
	43	* Magic header for a swap area. The first part of the union is
	44	* what the swap magic looks like for the old (limited to 128MB)
	45	* swap area format, the second part of the union adds - in the
	46	* old reserved area - some extra information. Note that the first
	47	* kilobyte is reserved for boot loader or disk label stuff...
	48	*
	49	* Having the magic at the end of the PAGE_SIZE makes detecting swap
	50	* areas somewhat tricky on machines that support multiple page sizes.
	51	* For 2.5 we'll probably want to move the magic to just beyond the
	52	* bootbits...
	53	*/
	54	union swap_header {
	55	struct {
	56	char reserved[PAGE_SIZE - 10];
	57	char magic[10]; /* SWAP-SPACE or SWAPSPACE2 */
	58	} magic;
	59	struct {
e8f03d02 AD	60	char bootbits[1024]; /* Space for disklabel etc. */
	61	__u32 version;
	62	__u32 last_page;
	63	__u32 nr_badpages;
	64	unsigned char sws_uuid[16];
	65	unsigned char sws_volume[16];
	66	__u32 padding[117];
	67	__u32 badpages[1];
1da177e4 LT	68	} info;
	69	};
	70
	71	/* A swap entry has to fit into a "unsigned long", as
	72	* the entry is hidden in the "index" field of the
	73	* swapper address space.
	74	*/
	75	typedef struct {
	76	unsigned long val;
	77	} swp_entry_t;
	78
	79	/*
	80	* current->reclaim_state points to one of these when a task is running
	81	* memory reclaim
	82	*/
	83	struct reclaim_state {
	84	unsigned long reclaimed_slab;
	85	};
	86
	87	#ifdef __KERNEL__
	88
	89	struct address_space;
	90	struct sysinfo;
	91	struct writeback_control;
	92	struct zone;
	93
	94	/*
	95	* A swap extent maps a range of a swapfile's PAGE_SIZE pages onto a range of
	96	* disk blocks. A list of swap extents maps the entire swapfile. (Where the
	97	* term `swapfile' refers to either a blockdevice or an IS_REG file. Apart
	98	* from setup, they're handled identically.
	99	*
	100	* We always assume that blocks are of size PAGE_SIZE.
	101	*/
	102	struct swap_extent {
	103	struct list_head list;
	104	pgoff_t start_page;
	105	pgoff_t nr_pages;
	106	sector_t start_block;
	107	};
	108
	109	/*
	110	* Max bad pages in the new format..
	111	*/
	112	#define __swapoffset(x) ((unsigned long)&((union swap_header *)0)->x)
	113	#define MAX_SWAP_BADPAGES \
	114	((__swapoffset(magic.magic) - __swapoffset(info.badpages)) / sizeof(int))
	115
	116	enum {
	117	SWP_USED = (1 << 0), /* is slot in swap_info[] used? */
	118	SWP_WRITEOK = (1 << 1), /* ok to write to this swap? */
	119	SWP_ACTIVE = (SWP_USED \| SWP_WRITEOK),
52b7efdb HD	120	/* add others here before... */
52b7efdb HD	121	SWP_SCANNING = (1 << 8), /* refcount in scan_swap_map */
1da177e4 LT	122	};
	123
	124	#define SWAP_CLUSTER_MAX 32
	125
	126	#define SWAP_MAP_MAX 0x7fff
	127	#define SWAP_MAP_BAD 0x8000
	128
	129	/*
	130	* The in-memory structure used to track swap areas.
1da177e4 LT	131	*/
	132	struct swap_info_struct {
	133	unsigned int flags;
5d337b91	134	int prio; /* swap priority */
1da177e4 LT	135	struct file *swap_file;
	136	struct block_device *bdev;
	137	struct list_head extent_list;
1da177e4 LT	138	struct swap_extent *curr_swap_extent;
	139	unsigned old_block_size;
	140	unsigned short * swap_map;
	141	unsigned int lowest_bit;
	142	unsigned int highest_bit;
	143	unsigned int cluster_next;
	144	unsigned int cluster_nr;
6eb396dc HD	145	unsigned int pages;
	146	unsigned int max;
	147	unsigned int inuse_pages;
1da177e4 LT	148	int next; /* next entry on swap list */
	149	};
	150
	151	struct swap_list_t {
	152	int head; /* head of priority-ordered swapfile list */
	153	int next; /* swapfile to be used next */
	154	};
	155
	156	/* Swap 50% full? Release swapcache more aggressively.. */
	157	#define vm_swap_full() (nr_swap_pages*2 < total_swap_pages)
	158
	159	/* linux/mm/oom_kill.c */
9b0f8b04	160	extern void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order);
8bc719d3 MS	161	extern int register_oom_notifier(struct notifier_block *nb);
8bc719d3 MS	162	extern int unregister_oom_notifier(struct notifier_block *nb);
1da177e4 LT	163
	164	/* linux/mm/memory.c */
	165	extern void swapin_readahead(swp_entry_t, unsigned long, struct vm_area_struct *);
	166
	167	/* linux/mm/page_alloc.c */
	168	extern unsigned long totalram_pages;
cb45b0e9	169	extern unsigned long totalreserve_pages;
1da177e4 LT	170	extern long nr_swap_pages;
	171	extern unsigned int nr_free_pages(void);
	172	extern unsigned int nr_free_pages_pgdat(pg_data_t *pgdat);
	173	extern unsigned int nr_free_buffer_pages(void);
	174	extern unsigned int nr_free_pagecache_pages(void);
	175
	176	/* linux/mm/swap.c */
	177	extern void FASTCALL(lru_cache_add(struct page *));
	178	extern void FASTCALL(lru_cache_add_active(struct page *));
	179	extern void FASTCALL(activate_page(struct page *));
	180	extern void FASTCALL(mark_page_accessed(struct page *));
	181	extern void lru_add_drain(void);
053837fc	182	extern int lru_add_drain_all(void);
1da177e4 LT	183	extern int rotate_reclaimable_page(struct page *page);
	184	extern void swap_setup(void);
	185
	186	/* linux/mm/vmscan.c */
69e05944 AM	187	extern unsigned long try_to_free_pages(struct zone **, gfp_t);
69e05944 AM	188	extern unsigned long shrink_all_memory(unsigned long nr_pages);
1da177e4	189	extern int vm_swappiness;
b20a3503	190	extern int remove_mapping(struct address_space mapping, struct page page);
bd1e22b8	191	extern long vm_total_pages;
b20a3503	192
9eeff239 CL	193	#ifdef CONFIG_NUMA
9eeff239 CL	194	extern int zone_reclaim_mode;
9614634f	195	extern int sysctl_min_unmapped_ratio;
0ff38490	196	extern int sysctl_min_slab_ratio;
9eeff239 CL	197	extern int zone_reclaim(struct zone *, gfp_t, unsigned int);
	198	#else
	199	#define zone_reclaim_mode 0
	200	static inline int zone_reclaim(struct zone *z, gfp_t mask, unsigned int order)
	201	{
	202	return 0;
	203	}
	204	#endif
	205
3218ae14 YG	206	extern int kswapd_run(int nid);
3218ae14 YG	207
1da177e4 LT	208	#ifdef CONFIG_MMU
	209	/* linux/mm/shmem.c */
	210	extern int shmem_unuse(swp_entry_t entry, struct page *page);
	211	#endif /* CONFIG_MMU */
	212
	213	extern void swap_unplug_io_fn(struct backing_dev_info , struct page );
	214
	215	#ifdef CONFIG_SWAP
	216	/* linux/mm/page_io.c */
	217	extern int swap_readpage(struct file , struct page );
	218	extern int swap_writepage(struct page page, struct writeback_control wbc);
	219	extern int rw_swap_page_sync(int, swp_entry_t, struct page *);
	220
	221	/* linux/mm/swap_state.c */
	222	extern struct address_space swapper_space;
	223	#define total_swapcache_pages swapper_space.nrpages
	224	extern void show_swap_cache_info(void);
1480a540	225	extern int add_to_swap(struct page *, gfp_t);
1da177e4 LT	226	extern void __delete_from_swap_cache(struct page *);
	227	extern void delete_from_swap_cache(struct page *);
	228	extern int move_to_swap_cache(struct page *, swp_entry_t);
	229	extern int move_from_swap_cache(struct page *, unsigned long,
	230	struct address_space *);
	231	extern void free_page_and_swap_cache(struct page *);
	232	extern void free_pages_and_swap_cache(struct page **, int);
	233	extern struct page * lookup_swap_cache(swp_entry_t);
	234	extern struct page * read_swap_cache_async(swp_entry_t, struct vm_area_struct *vma,
	235	unsigned long addr);
	236	/* linux/mm/swapfile.c */
	237	extern long total_swap_pages;
	238	extern unsigned int nr_swapfiles;
1da177e4 LT	239	extern void si_swapinfo(struct sysinfo *);
1da177e4 LT	240	extern swp_entry_t get_swap_page(void);
f577eb30	241	extern swp_entry_t get_swap_page_of_type(int);
1da177e4 LT	242	extern int swap_duplicate(swp_entry_t);
	243	extern int valid_swaphandles(swp_entry_t, unsigned long *);
	244	extern void swap_free(swp_entry_t);
	245	extern void free_swap_and_cache(swp_entry_t);
f577eb30 RW	246	extern int swap_type_of(dev_t);
f577eb30 RW	247	extern unsigned int count_swap_pages(int, int);
1da177e4 LT	248	extern sector_t map_swap_page(struct swap_info_struct *, pgoff_t);
	249	extern struct swap_info_struct *get_swap_info_struct(unsigned);
	250	extern int can_share_swap_page(struct page *);
	251	extern int remove_exclusive_swap_page(struct page *);
	252	struct backing_dev_info;
	253
5d337b91	254	extern spinlock_t swap_lock;
1da177e4 LT	255
	256	/* linux/mm/thrash.c */
	257	extern struct mm_struct * swap_token_mm;
	258	extern unsigned long swap_token_default_timeout;
	259	extern void grab_swap_token(void);
	260	extern void __put_swap_token(struct mm_struct *);
	261
	262	static inline int has_swap_token(struct mm_struct *mm)
	263	{
	264	return (mm == swap_token_mm);
	265	}
	266
	267	static inline void put_swap_token(struct mm_struct *mm)
	268	{
	269	if (has_swap_token(mm))
	270	__put_swap_token(mm);
	271	}
	272
f7b7fd8f RR	273	static inline void disable_swap_token(void)
	274	{
	275	put_swap_token(swap_token_mm);
	276	}
	277
1da177e4 LT	278	#else /* CONFIG_SWAP */
	279
	280	#define total_swap_pages 0
	281	#define total_swapcache_pages 0UL
	282
	283	#define si_swapinfo(val) \
	284	do { (val)->freeswap = (val)->totalswap = 0; } while (0)
9ae5b3c7 OH	285	/* only sparc can not include linux/pagemap.h in this file
9ae5b3c7 OH	286	* so leave page_cache_release and release_pages undeclared... */
1da177e4 LT	287	#define free_page_and_swap_cache(page) \
	288	page_cache_release(page)
	289	#define free_pages_and_swap_cache(pages, nr) \
	290	release_pages((pages), (nr), 0);
	291
bd96b9eb CK	292	static inline void show_swap_cache_info(void)
	293	{
	294	}
	295
	296	static inline void free_swap_and_cache(swp_entry_t swp)
	297	{
	298	}
	299
	300	static inline int swap_duplicate(swp_entry_t swp)
	301	{
	302	return 0;
	303	}
	304
	305	static inline void swap_free(swp_entry_t swp)
	306	{
	307	}
	308
	309	static inline struct page *read_swap_cache_async(swp_entry_t swp,
	310	struct vm_area_struct *vma, unsigned long addr)
	311	{
	312	return NULL;
	313	}
	314
	315	static inline struct page *lookup_swap_cache(swp_entry_t swp)
	316	{
	317	return NULL;
	318	}
	319
	320	static inline int valid_swaphandles(swp_entry_t entry, unsigned long *offset)
	321	{
	322	return 0;
	323	}
	324
e6333fd4	325	#define can_share_swap_page(p) (page_mapcount(p) == 1)
bd96b9eb CK	326
	327	static inline int move_to_swap_cache(struct page *page, swp_entry_t entry)
	328	{
	329	return 1;
	330	}
	331
	332	static inline int move_from_swap_cache(struct page *page, unsigned long index,
	333	struct address_space *mapping)
	334	{
	335	return 1;
	336	}
	337
	338	static inline void __delete_from_swap_cache(struct page *page)
	339	{
	340	}
	341
	342	static inline void delete_from_swap_cache(struct page *page)
	343	{
	344	}
	345
1da177e4 LT	346	#define swap_token_default_timeout 0
	347
	348	static inline int remove_exclusive_swap_page(struct page *p)
	349	{
	350	return 0;
	351	}
	352
	353	static inline swp_entry_t get_swap_page(void)
	354	{
	355	swp_entry_t entry;
	356	entry.val = 0;
	357	return entry;
	358	}
	359
	360	/* linux/mm/thrash.c */
	361	#define put_swap_token(x) do { } while(0)
	362	#define grab_swap_token() do { } while(0)
	363	#define has_swap_token(x) 0
f7b7fd8f	364	#define disable_swap_token() do { } while(0)
1da177e4 LT	365
	366	#endif /* CONFIG_SWAP */
	367	#endif /* __KERNEL__*/
	368	#endif /* _LINUX_SWAP_H */