I don’t know anything about japanese music, but here some notes on chinese music:
Japanese music may be, but chinese music is definitive NOT mostly pentatonic. I’m doing some musicologic studies of chinese music at the moment, and I really heard many styles of chinese music and many songs for each style, let it be vocal music or instrumental or peking opera or whatever.
I heard one piece with a real pentatonic scale, the other ~100 of them were diatonic, often more or less Gmaj (or equivalent keys) with a sharp seventh (arabians would call it a “quarter note” since its frequency is located somewhere between the seventh and the octave which is a step of a semitone) and leaving out the first 2, 3 notes of the second octave.
Chinese flutes (they don’t use fipple flutes traditionally by the way, there is a flute called “xiao”, but it’s more related to the japanese shakuhachi) have usually 6 holes (some flutes of specific tribes may have more or less) tuned to the scale I mentioned above, the ones without 7th hole for the ricepaper called uta (as Screech mentioned), the ones with rice paper hole (it’s called “mirliton” by the way and the same principle is used by the kazoo known in modern jazz) are called “dizi”, the ones in Gmaj (I own one) “dizi huang” which more or less means “yellow flute”. No idea why, a chinese friend told me that. 
The chinese style of playing is more plain than the irish, they also cut the notes (never heard about pads), but I can’t recall a recording were any more complex ornamentation was used. Instead, notes are mostly tongued and especially for slow pieces VERY much diaphragm vibrato is used.
Chinese music itself often is not devided into parts as we know from ITM. Chinese musicians use to tell stories with their instrument, and so a specific phrase hardly never is repeated. For example, I heard a piece called “the waves of the river taking their way down to the ocean” (if I recall correctly) played on qin, a pentatonic, but fingere zither with five strings tuned to a pentatonic scale beginning on G. And what am I supposed to say, it did not sound like a song or tune, it sounded like a river’s gurgling from the fountain to the ocean, nothing more and nothing less. Not important that a musical instrument was used to tell the story, it also could have been told by a chinese storyteller. You hear the name, then the song, and think, “yes, that’s it”. It’s really fascinating.
If you have further question, feel free to contact me…
Greetings,
G.
Ah, forgot to say: I can’t remember who exactly was it, but a chinese tribe uses to make a flute with one embouchure hole in the middle of the tube, two open ends and one or two tone holes on each end for fingering notes. Those things sound quite interesting. Dunno how they’re called, if you’re interested, I’ll ask my professor for it.