/proc/bus/pci

[Albert Cahalan]

I notice that /proc/bus/pci doesn't offer a sane
interface for multiple PCI domains and choice of BAR.
What do people think of this?

bus/pci/00/00.0 -> ../hose0/bus0/dev0/fn0/config-space
bus/pci/hose0/bus0/dev0/fn0/config-space
bus/pci/hose0/bus0/dev0/fn0/bar0
bus/pci/hose0/bus0/dev0/fn0/bar1
bus/pci/hose0/bus0/dev0/fn0/bar2
bus/pci/hose0/bus0/dev0/fn0/status

Then with some mmap flags, the nasty ioctl() stuff
won't be needed anymore. It can die during 2.7.xx
development. If MAP_MMIO isn't generally acceptable,
then it could be via filename suffixes. (eeew, IMHO)

One remaining problem is permission. Any complaints
about implementing chmod() for those? Since this
does bypass capabilities, a mount option might be
used to enable it.

As alternatives to /proc changes, a distinct filesystem
could be developed or sysfs could be abused.