swapfile: convert __try_to_reclaim_swap() to use a folio

				 unsigned long offset, unsigned long flags)

{

	swp_entry_t entry = swp_entry(si->type, offset);

	struct page *page;

	struct folio *folio;

	int ret = 0;

	page = find_get_page(swap_address_space(entry), offset);

	if (!page)

	folio = filemap_get_folio(swap_address_space(entry), offset);

	if (!folio)

		return 0;

	/*

	 * When this function is called from scan_swap_map_slots() and it's

	 * called by vmscan.c at reclaiming pages. So, we hold a lock on a page,

	 * called by vmscan.c at reclaiming folios. So we hold a folio lock

	 * here. We have to use trylock for avoiding deadlock. This is a special

	 * case and you should use try_to_free_swap() with explicit lock_page()

	 * case and you should use folio_free_swap() with explicit folio_lock()

	 * in usual operations.

	 */

	if (trylock_page(page)) {

	if (folio_trylock(folio)) {

		if ((flags & TTRS_ANYWAY) ||

		    ((flags & TTRS_UNMAPPED) && !page_mapped(page)) ||

		    ((flags & TTRS_FULL) && mem_cgroup_swap_full(page)))

			ret = try_to_free_swap(page);

		unlock_page(page);

		    ((flags & TTRS_UNMAPPED) && !folio_mapped(folio)) ||

		    ((flags & TTRS_FULL) && mem_cgroup_swap_full(&folio->page)))

			ret = folio_free_swap(folio);

		folio_unlock(folio);

	}

	put_page(page);

	folio_put(folio);

	return ret;

}