> > > answer should probably be not at all).
> > correct. ACS is a *bridge* property.
> > btwn the functions within a device.
> > and allow parent bridge re-route it back down if peer-to-peer is desired.
> > determine this status about a device (via pci cfg/cap space).
ACS check for multifunction.  Does this start to make more sense?
bus for use in determining the boundaries of an iommu group.
Logic for this extracted from libvirt.
+ * filters out flags that are not implemented on multifunction devices.
+ * any step along the way does not support the required flags, return false.