disk_alloc_nowait is just like disk_alloc, but won't wait for memory and may
return NULL. It's for drivers that need to create a disk from a non-sleepable
On second thought, I'm going to abandon this approach and schedule the cam register routine into a taskqueue so we can sleep. There's no good retry mechanism here, and adding one would make things more complicated. We can switch to waiting for memory to have a more robust system with simpler code. This also matches at least some of the feedback I've received privately (thanks Chuck). I'll post that review when I have it done.