PCI rework

[Benjamin Herrenschmidt]

> How should it do that.  Providing an additional memory region?  How
> are those regions supposed to be numbered?  Can your libpciaccess
> interface deal with them?  The current X interface can, because all it
> takes is the (physical) address on the pci bus and the size of the
> region to be mapped.

Except that the whole notion of a physical address doesn't necessarily
mean anything... you can have  multiple domains with different address
mappings and the BAR <-> CPU bus address mapping for a given domain may
not be 1:1 etc...

You do NOT want to put knowledge of that stuff in the X server.

Ben.