nvme: Nvme controller generated events

[imp]

Summary

Interface for the nvme driver notifying its children of different
events: async notifications, namespace events and device failure. These
aren't yet connected.

Sponsored by: Netflix

[jhb]

sys/dev/nvme/nvmec_if.m

9

Just "nvme"?

18

I would perhaps name these as ns_added, ns_removed, ns_changed similar to BUS_CHILD_DELETED.

26

We can afford to spell out "remove" I think.

42

controller_failed?

49

handle_aen?

[imp]

sys/dev/nvme/nvmec_if.m

9

I chose nvmec to mirror the pcib vs pci separation. But I've never known quite how to differentiate the interfaces that children need to implement that this driver will call from the interfaces I implement for my children to call. Usually it's just one or the other, but I was anticipating needing to have upcalls as well as downcalls (though I couldn't tell you which is which in newbus speak).

18

That's not a bad idea. I hacked through these interfaces in a hurry.

42

Likely better. This name is the same as we had before with the 'consumer' thing.

49

Same.

[imp]

Update per review, add missing change

[imp]

Update per review and rebase over resize changes... woof.