/* 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); int __swap_writepage(struct page *page, struct writeback_control *wbc); /* 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 folio *folio, swp_entry_t entry, gfp_t gfp, void **shadowp); void __delete_from_swap_cache(struct folio *folio, swp_entry_t entry, void *shadow); void delete_from_swap_cache(struct folio *folio); void clear_shadow_from_swap_cache(int type, unsigned long begin, unsigned long end); struct folio *swap_cache_get_folio(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 folio_swap_flags(struct folio *folio) { return page_swap_info(&folio->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 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 folio *swap_cache_get_folio(swp_entry_t entry, 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 folio *folio, swp_entry_t entry, gfp_t gfp_mask, void **shadowp) { return -1; } static inline void __delete_from_swap_cache(struct folio *folio, swp_entry_t entry, void *shadow) { } static inline void delete_from_swap_cache(struct folio *folio) { } static inline void clear_shadow_from_swap_cache(int type, unsigned long begin, unsigned long end) { } static inline unsigned int folio_swap_flags(struct folio *folio) { return 0; } #endif /* CONFIG_SWAP */ #endif /* _MM_SWAP_H */