If the amount of uploaded (and not matched) tunes is over 5 Go, will I have to pay for extra space as for any other iCloud use ?

It is not said clearly that I have to purchase extra space in my iCloud if I get to upload more than 5 Go of music when I subscribe to iTunes Match, although I can't say why I wouldn't have to. Also is it possible to pre-check how many of my tunes are to be uploaded and hosted in the cloud and how many are already on iTunes and just need to be matched ?