Literally: “many stones” – “many stones” – fall – fall
Alternately: Generous; tolerant; forgiving; not stressing over little things.
Notes: This is a phrase that creates emphasis by doubling: 磊落 (rairaku) on its own has the same meaning. 豪放磊落 (gouhou rairaku) is a synonym, while 小心翼翼 (shoushin yokuyoku) is considered an antonym, although it focuses more on timidity than uptightness.
Naturally, replacing each doubled character with the doubling mark 々 as 磊々落々 is perfectly acceptable.