[linux-2.6-block.git] / mm / swap.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _MM_SWAP_H
#define _MM_SWAP_H

#ifdef CONFIG_SWAP
#include <linux/blk_types.h> /* for bio_end_io_t */

/* linux/mm/page_io.c */
int sio_pool_init(void);
struct swap_iocb;
int swap_readpage(struct page *page, bool do_poll,
		  struct swap_iocb **plug);
void __swap_read_unplug(struct swap_iocb *plug);
static inline void swap_read_unplug(struct swap_iocb *plug)
{
	if (unlikely(plug))
		__swap_read_unplug(plug);
}
int swap_writepage(struct page *page, struct writeback_control *wbc);
void end_swap_bio_write(struct bio *bio);
int __swap_writepage(struct page *page, struct writeback_control *wbc,
		     bio_end_io_t end_write_func);

/* linux/mm/swap_state.c */
/* One swap address space for each 64M swap space */
#define SWAP_ADDRESS_SPACE_SHIFT	14
#define SWAP_ADDRESS_SPACE_PAGES	(1 << SWAP_ADDRESS_SPACE_SHIFT)
extern struct address_space *swapper_spaces[];
#define swap_address_space(entry)			    \
	(&swapper_spaces[swp_type(entry)][swp_offset(entry) \
		>> SWAP_ADDRESS_SPACE_SHIFT])

void show_swap_cache_info(void);
int add_to_swap(struct page *page);
void *get_shadow_from_swap_cache(swp_entry_t entry);
int add_to_swap_cache(struct page *page, swp_entry_t entry,
		      gfp_t gfp, void **shadowp);
void __delete_from_swap_cache(struct page *page,
			      swp_entry_t entry, void *shadow);
void delete_from_swap_cache(struct page *page);
void clear_shadow_from_swap_cache(int type, unsigned long begin,
				  unsigned long end);
void free_swap_cache(struct page *page);
struct page *lookup_swap_cache(swp_entry_t entry,
			       struct vm_area_struct *vma,
			       unsigned long addr);
struct page *find_get_incore_page(struct address_space *mapping, pgoff_t index);

struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
				   struct vm_area_struct *vma,
				   unsigned long addr,
				   bool do_poll,
				   struct swap_iocb **plug);
struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
				     struct vm_area_struct *vma,
				     unsigned long addr,
				     bool *new_page_allocated);
struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
				    struct vm_fault *vmf);
struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
			      struct vm_fault *vmf);

static inline unsigned int page_swap_flags(struct page *page)
{
	return page_swap_info(page)->flags;
}
#else /* CONFIG_SWAP */
struct swap_iocb;
static inline int swap_readpage(struct page *page, bool do_poll,
				struct swap_iocb **plug)
{
	return 0;
}

static inline struct address_space *swap_address_space(swp_entry_t entry)
{
	return NULL;
}

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

static inline void show_swap_cache_info(void)
{
}

static inline struct page *swap_cluster_readahead(swp_entry_t entry,
				gfp_t gfp_mask, struct vm_fault *vmf)
{
	return NULL;
}

static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
			struct vm_fault *vmf)
{
	return NULL;
}

static inline int swap_writepage(struct page *p, struct writeback_control *wbc)
{
	return 0;
}

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

static inline
struct page *find_get_incore_page(struct address_space *mapping, pgoff_t index)
{
	return find_get_page(mapping, index);
}

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

static inline void *get_shadow_from_swap_cache(swp_entry_t entry)
{
	return NULL;
}

static inline int add_to_swap_cache(struct page *page, swp_entry_t entry,
					gfp_t gfp_mask, void **shadowp)
{
	return -1;
}

static inline void __delete_from_swap_cache(struct page *page,
					swp_entry_t entry, void *shadow)
{
}

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

static inline void clear_shadow_from_swap_cache(int type, unsigned long begin,
				unsigned long end)
{
}

static inline unsigned int page_swap_flags(struct page *page)
{
	return 0;
}
#endif /* CONFIG_SWAP */
#endif /* _MM_SWAP_H */
Commit	Line	Data
014bb1de N	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef _MM_SWAP_H
	3	#define _MM_SWAP_H
	4
	5	#ifdef CONFIG_SWAP
	6	#include <linux/blk_types.h> /* for bio_end_io_t */
	7
	8	/* linux/mm/page_io.c */
e1209d3a	9	int sio_pool_init(void);
5169b844 N	10	struct swap_iocb;
	11	int swap_readpage(struct page *page, bool do_poll,
	12	struct swap_iocb **plug);
	13	void __swap_read_unplug(struct swap_iocb *plug);
	14	static inline void swap_read_unplug(struct swap_iocb *plug)
	15	{
	16	if (unlikely(plug))
	17	__swap_read_unplug(plug);
	18	}
014bb1de N	19	int swap_writepage(struct page page, struct writeback_control wbc);
	20	void end_swap_bio_write(struct bio *bio);
	21	int __swap_writepage(struct page page, struct writeback_control wbc,
	22	bio_end_io_t end_write_func);
	23
	24	/* linux/mm/swap_state.c */
	25	/* One swap address space for each 64M swap space */
	26	#define SWAP_ADDRESS_SPACE_SHIFT 14
	27	#define SWAP_ADDRESS_SPACE_PAGES (1 << SWAP_ADDRESS_SPACE_SHIFT)
	28	extern struct address_space *swapper_spaces[];
	29	#define swap_address_space(entry) \
	30	(&swapper_spaces[swp_type(entry)][swp_offset(entry) \
	31	>> SWAP_ADDRESS_SPACE_SHIFT])
	32
	33	void show_swap_cache_info(void);
	34	int add_to_swap(struct page *page);
	35	void *get_shadow_from_swap_cache(swp_entry_t entry);
	36	int add_to_swap_cache(struct page *page, swp_entry_t entry,
	37	gfp_t gfp, void **shadowp);
	38	void __delete_from_swap_cache(struct page *page,
	39	swp_entry_t entry, void *shadow);
	40	void delete_from_swap_cache(struct page *page);
	41	void clear_shadow_from_swap_cache(int type, unsigned long begin,
	42	unsigned long end);
	43	void free_swap_cache(struct page *page);
	44	struct page *lookup_swap_cache(swp_entry_t entry,
	45	struct vm_area_struct *vma,
	46	unsigned long addr);
	47	struct page find_get_incore_page(struct address_space mapping, pgoff_t index);
	48
	49	struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
	50	struct vm_area_struct *vma,
	51	unsigned long addr,
5169b844 N	52	bool do_poll,
5169b844 N	53	struct swap_iocb **plug);
014bb1de N	54	struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
	55	struct vm_area_struct *vma,
	56	unsigned long addr,
	57	bool *new_page_allocated);
	58	struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
	59	struct vm_fault *vmf);
	60	struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
	61	struct vm_fault *vmf);
	62
d791ea67 N	63	static inline unsigned int page_swap_flags(struct page *page)
	64	{
	65	return page_swap_info(page)->flags;
	66	}
014bb1de	67	#else /* CONFIG_SWAP */
5169b844 N	68	struct swap_iocb;
	69	static inline int swap_readpage(struct page *page, bool do_poll,
	70	struct swap_iocb **plug)
014bb1de N	71	{
	72	return 0;
	73	}
	74
	75	static inline struct address_space *swap_address_space(swp_entry_t entry)
	76	{
	77	return NULL;
	78	}
	79
	80	static inline void free_swap_cache(struct page *page)
	81	{
	82	}
	83
	84	static inline void show_swap_cache_info(void)
	85	{
	86	}
	87
	88	static inline struct page *swap_cluster_readahead(swp_entry_t entry,
	89	gfp_t gfp_mask, struct vm_fault *vmf)
	90	{
	91	return NULL;
	92	}
	93
	94	static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
	95	struct vm_fault *vmf)
	96	{
	97	return NULL;
	98	}
	99
	100	static inline int swap_writepage(struct page p, struct writeback_control wbc)
	101	{
	102	return 0;
	103	}
	104
	105	static inline struct page *lookup_swap_cache(swp_entry_t swp,
	106	struct vm_area_struct *vma,
	107	unsigned long addr)
	108	{
	109	return NULL;
	110	}
	111
	112	static inline
	113	struct page find_get_incore_page(struct address_space mapping, pgoff_t index)
	114	{
	115	return find_get_page(mapping, index);
	116	}
	117
	118	static inline int add_to_swap(struct page *page)
	119	{
	120	return 0;
	121	}
	122
	123	static inline void *get_shadow_from_swap_cache(swp_entry_t entry)
	124	{
	125	return NULL;
	126	}
	127
	128	static inline int add_to_swap_cache(struct page *page, swp_entry_t entry,
	129	gfp_t gfp_mask, void **shadowp)
	130	{
	131	return -1;
	132	}
	133
	134	static inline void __delete_from_swap_cache(struct page *page,
135	swp_entry_t entry, void *shadow)
136	{
137	}
138
139	static inline void delete_from_swap_cache(struct page *page)
140	{
141	}
142
143	static inline void clear_shadow_from_swap_cache(int type, unsigned long begin,
144	unsigned long end)
145	{
146	}
147
d791ea67 N	148	static inline unsigned int page_swap_flags(struct page *page)
	149	{
	150	return 0;
	151	}
014bb1de N	152	#endif /* CONFIG_SWAP */
014bb1de N	153	#endif /* _MM_SWAP_H */