[linux.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);
}
void swap_write_unplug(struct swap_iocb *sio);
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);
bool add_to_swap(struct folio *folio);
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 void swap_write_unplug(struct swap_iocb *sio)
{
}

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 bool add_to_swap(struct folio *folio)
{
	return false;
}

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	}
2282679f	19	void swap_write_unplug(struct swap_iocb *sio);
014bb1de N	20	int swap_writepage(struct page page, struct writeback_control wbc);
	21	void end_swap_bio_write(struct bio *bio);
	22	int __swap_writepage(struct page page, struct writeback_control wbc,
	23	bio_end_io_t end_write_func);
	24
	25	/* linux/mm/swap_state.c */
	26	/* One swap address space for each 64M swap space */
	27	#define SWAP_ADDRESS_SPACE_SHIFT 14
	28	#define SWAP_ADDRESS_SPACE_PAGES (1 << SWAP_ADDRESS_SPACE_SHIFT)
	29	extern struct address_space *swapper_spaces[];
	30	#define swap_address_space(entry) \
	31	(&swapper_spaces[swp_type(entry)][swp_offset(entry) \
	32	>> SWAP_ADDRESS_SPACE_SHIFT])
	33
	34	void show_swap_cache_info(void);
09c02e56	35	bool add_to_swap(struct folio *folio);
014bb1de N	36	void *get_shadow_from_swap_cache(swp_entry_t entry);
	37	int add_to_swap_cache(struct page *page, swp_entry_t entry,
	38	gfp_t gfp, void **shadowp);
	39	void __delete_from_swap_cache(struct page *page,
	40	swp_entry_t entry, void *shadow);
	41	void delete_from_swap_cache(struct page *page);
	42	void clear_shadow_from_swap_cache(int type, unsigned long begin,
	43	unsigned long end);
	44	void free_swap_cache(struct page *page);
	45	struct page *lookup_swap_cache(swp_entry_t entry,
	46	struct vm_area_struct *vma,
	47	unsigned long addr);
	48	struct page find_get_incore_page(struct address_space mapping, pgoff_t index);
	49
	50	struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
	51	struct vm_area_struct *vma,
	52	unsigned long addr,
5169b844 N	53	bool do_poll,
5169b844 N	54	struct swap_iocb **plug);
014bb1de N	55	struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
	56	struct vm_area_struct *vma,
	57	unsigned long addr,
	58	bool *new_page_allocated);
	59	struct page *swap_cluster_readahead(swp_entry_t entry, gfp_t flag,
	60	struct vm_fault *vmf);
	61	struct page *swapin_readahead(swp_entry_t entry, gfp_t flag,
	62	struct vm_fault *vmf);
	63
d791ea67 N	64	static inline unsigned int page_swap_flags(struct page *page)
	65	{
	66	return page_swap_info(page)->flags;
	67	}
014bb1de	68	#else /* CONFIG_SWAP */
5169b844 N	69	struct swap_iocb;
	70	static inline int swap_readpage(struct page *page, bool do_poll,
	71	struct swap_iocb **plug)
014bb1de N	72	{
	73	return 0;
	74	}
2282679f N	75	static inline void swap_write_unplug(struct swap_iocb *sio)
	76	{
	77	}
014bb1de N	78
	79	static inline struct address_space *swap_address_space(swp_entry_t entry)
	80	{
	81	return NULL;
	82	}
	83
	84	static inline void free_swap_cache(struct page *page)
	85	{
	86	}
	87
	88	static inline void show_swap_cache_info(void)
	89	{
	90	}
	91
	92	static inline struct page *swap_cluster_readahead(swp_entry_t entry,
	93	gfp_t gfp_mask, struct vm_fault *vmf)
	94	{
	95	return NULL;
	96	}
	97
	98	static inline struct page *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask,
	99	struct vm_fault *vmf)
	100	{
	101	return NULL;
	102	}
	103
	104	static inline int swap_writepage(struct page p, struct writeback_control wbc)
	105	{
	106	return 0;
	107	}
	108
	109	static inline struct page *lookup_swap_cache(swp_entry_t swp,
	110	struct vm_area_struct *vma,
	111	unsigned long addr)
	112	{
	113	return NULL;
	114	}
	115
	116	static inline
	117	struct page find_get_incore_page(struct address_space mapping, pgoff_t index)
	118	{
	119	return find_get_page(mapping, index);
	120	}
	121
09c02e56	122	static inline bool add_to_swap(struct folio *folio)
014bb1de	123	{
09c02e56	124	return false;
014bb1de N	125	}
	126
	127	static inline void *get_shadow_from_swap_cache(swp_entry_t entry)
	128	{
	129	return NULL;
	130	}
	131
	132	static inline int add_to_swap_cache(struct page *page, swp_entry_t entry,
	133	gfp_t gfp_mask, void **shadowp)
	134	{
	135	return -1;
	136	}
	137
	138	static inline void __delete_from_swap_cache(struct page *page,
	139	swp_entry_t entry, void *shadow)
	140	{
	141	}
	142
	143	static inline void delete_from_swap_cache(struct page *page)
	144	{
	145	}
	146
	147	static inline void clear_shadow_from_swap_cache(int type, unsigned long begin,
	148	unsigned long end)
	149	{
	150	}
	151
d791ea67 N	152	static inline unsigned int page_swap_flags(struct page *page)
	153	{
	154	return 0;
	155	}
014bb1de N	156	#endif /* CONFIG_SWAP */
014bb1de N	157	#endif /* _MM_SWAP_H */