diff options
Diffstat (limited to 'include/linux/frontswap.h')
-rw-r--r-- | include/linux/frontswap.h | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/include/linux/frontswap.h b/include/linux/frontswap.h new file mode 100644 index 000000000000..7c62423c67de --- /dev/null +++ b/include/linux/frontswap.h @@ -0,0 +1,92 @@ +#ifndef _LINUX_FRONTSWAP_H +#define _LINUX_FRONTSWAP_H + +#include <linux/swap.h> +#include <linux/mm.h> + +struct frontswap_ops { + void (*init)(unsigned); + int (*put_page)(unsigned, pgoff_t, struct page *); + int (*get_page)(unsigned, pgoff_t, struct page *); + void (*flush_page)(unsigned, pgoff_t); + void (*flush_area)(unsigned); +}; + +extern int frontswap_enabled; +extern struct frontswap_ops + frontswap_register_ops(struct frontswap_ops *ops); +extern void frontswap_shrink(unsigned long); +extern unsigned long frontswap_curr_pages(void); + +extern void __frontswap_init(unsigned type); +extern int __frontswap_put_page(struct page *page); +extern int __frontswap_get_page(struct page *page); +extern void __frontswap_flush_page(unsigned, pgoff_t); +extern void __frontswap_flush_area(unsigned); + +#ifndef CONFIG_FRONTSWAP +/* all inline routines become no-ops and all externs are ignored */ +#define frontswap_enabled (0) +#endif + +static inline int frontswap_test(struct swap_info_struct *sis, pgoff_t offset) +{ + int ret = 0; + + if (frontswap_enabled && sis->frontswap_map) + ret = test_bit(offset % BITS_PER_LONG, + &sis->frontswap_map[offset/BITS_PER_LONG]); + return ret; +} + +static inline void frontswap_set(struct swap_info_struct *sis, pgoff_t offset) +{ + if (frontswap_enabled && sis->frontswap_map) + set_bit(offset % BITS_PER_LONG, + &sis->frontswap_map[offset/BITS_PER_LONG]); +} + +static inline void frontswap_clear(struct swap_info_struct *sis, pgoff_t offset) +{ + if (frontswap_enabled && sis->frontswap_map) + clear_bit(offset % BITS_PER_LONG, + &sis->frontswap_map[offset/BITS_PER_LONG]); +} + +static inline int frontswap_put_page(struct page *page) +{ + int ret = -1; + + if (frontswap_enabled) + ret = __frontswap_put_page(page); + return ret; +} + +static inline int frontswap_get_page(struct page *page) +{ + int ret = -1; + + if (frontswap_enabled) + ret = __frontswap_get_page(page); + return ret; +} + +static inline void frontswap_flush_page(unsigned type, pgoff_t offset) +{ + if (frontswap_enabled) + __frontswap_flush_page(type, offset); +} + +static inline void frontswap_flush_area(unsigned type) +{ + if (frontswap_enabled) + __frontswap_flush_area(type); +} + +static inline void frontswap_init(unsigned type) +{ + if (frontswap_enabled) + __frontswap_init(type); +} + +#endif /* _LINUX_FRONTSWAP_H */ |