map_aperture
aperture_id (*map_aperture)(uint8 bus, uint8 device, uint8 function,
map_aperture,
info.aperture = gGART->map_aperture(info.pci->bus, info.pci->device,
aperture_id aperture = sGART->map_aperture(0, 0, 0, 0, &apertureBase);