xen: OSV xenbus

Operating Systems / OSv - Glauber Costa [cloudius-systems.com] - 13 August 2013 08:38 UTC

This commit includes the basic translation layer so we can support BSD devices for Xen as is. I believe there is room for improvement, but that provides a
very good starting point. I would like to provide you guys with a smaller commit, but it is quite cumbersome to separate the device implementation from the bus implementation per se. Part of it is due to the way Xen does things.

For instance: when we are talking virtio devices, each of them will have its own pci device. For xen, only one pci device will be exposed, with its own interrupt, and that will be the xenbus. The xenbus is then responsible for querying the xenstore and figuring out which devices are there. Maybe there is a different way of doing things (I believe for instance that there is no reason to have shared interrupts between all devices) but that is the way BSD does things. And about the bus-is-the-device, even Linux as far as I know.

Another thing to note, is that BSD devices registered with a device_method_t seem to be fully hierarchical. I am not doing it this way here (I am mostly ignoring the xenbus device_method_t definitions), which means there are a lot of assumptions that probably won't hold with other kinds of drivers. But it should not be hard to extend, and that simplifies things.

2ee1119 xen: OSV xenbus
drivers/xenfront-xenbus.cc | 285 ++++++++++++++++++++++++++++++++++++++++++++
drivers/xenfront-xenbus.hh | 53 ++++++++
drivers/xenfront.cc | 69 +++++++++++
drivers/xenfront.hh | 72 +++++++++++
4 files changed, 479 insertions(+)

Upstream: github.com

  • Share