[Qemu-devel] [RFC] Device isolation infrastructure v2

[David Gibson]

Here's the second spin of my preferred approach to handling grouping
of devices for safe assignment to guests.

Changes since v1:
 * Many name changes and file moves for improved consistency
 * Bugfixes and cleanups
 * The interface to the next layer up is considerably fleshed out,
   although it still needs work.
 * Example initialization of groups for p5ioc2 and p7ioc.

TODO:
 * Need sample initialization of groups for intel and/or amd iommus
 * Use of sysfs attributes to control group permission is probably a
   mistake.  Although it seems a bit odd, registering a chardev for
   each group is probably better, because perms can be set from udev
   rules, just like everything else.
 * Need more details of what the binder structure will need to
   contain.
 * Handle complete removal of groups.
 * Clarify what will need to happen on the hot unplug path.