Well if what I think is right it goes like this.
You have the Low pressure oil pump that supplies oil the the crank, cam bearings, lifters, and turbo. don't know what order they are supplied though.
the low pressure oil pump also feeds the HPOP resevoir where the oil is fed to the hpop, from the hpop to the hp oil rail / injectors, then from there I would assume back to the pan.
Not sure though, That is just my take on it.