map_swap_page 249 include/linux/swap.h extern sector_t map_swap_page(struct swap_info_struct *, pgoff_t); map_swap_page 33 mm/page_io.c bio->bi_sector = map_swap_page(sis, swp_offset(entry)) * map_swap_page 999 mm/swapfile.c return (sis->flags & SWP_WRITEOK) ? map_swap_page(sis, offset) : 0;