swap: use bvec_set_page to initialize bvecs

Use the bvec_set_page helper to initialize bvecs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230203150634.3199647-20-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

mm/page_io.c

@@ -318,9 +318,7 @@ static int swap_writepage_fs(struct page *page, struct writeback_control *wbc)
 		sio->pages = 0;
 		sio->len = 0;
 	}
-	sio->bvec[sio->pages].bv_page = page;
-	sio->bvec[sio->pages].bv_len = thp_size(page);
-	sio->bvec[sio->pages].bv_offset = 0;
+	bvec_set_page(&sio->bvec[sio->pages], page, thp_size(page), 0);
 	sio->len += thp_size(page);
 	sio->pages += 1;
 	if (sio->pages == ARRAY_SIZE(sio->bvec) || !wbc->swap_plug) {
@@ -432,9 +430,7 @@ static void swap_readpage_fs(struct page *page,
 		sio->pages = 0;
 		sio->len = 0;
 	}
-	sio->bvec[sio->pages].bv_page = page;
-	sio->bvec[sio->pages].bv_len = thp_size(page);
-	sio->bvec[sio->pages].bv_offset = 0;
+	bvec_set_page(&sio->bvec[sio->pages], page, thp_size(page), 0);
 	sio->len += thp_size(page);
 	sio->pages += 1;
 	if (sio->pages == ARRAY_SIZE(sio->bvec) || !plug) {