diff --git a/include/linux/bio.h b/include/linux/bio.h
index b893418c3cc0..f193aef4fac0 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -294,7 +294,7 @@ static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio,
 
 	fi->folio = page_folio(bvec->bv_page);
 	fi->offset = bvec->bv_offset +
-			PAGE_SIZE * (bvec->bv_page - &fi->folio->page);
+			PAGE_SIZE * folio_page_idx(fi->folio, bvec->bv_page);
 	fi->_seg_count = bvec->bv_len;
 	fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count);
 	fi->_next = folio_next(fi->folio);