start on being able to safely run io through the midlayer without the kernel biglock. the plan is to have the midlayer assume its running without the biglock, but that it cant call adapters or devices without taking the biglock first.
start on being able to safely run io through the midlayer without
the kernel biglock. the plan is to have the midlayer assume its
running without the biglock, but that it cant call adapters or
devices without taking the biglock first.

this diff just wraps the calls to the adapter iopool get and put
handlers up in the biglock.

this is safe now because of kettenis' commit to src/sys/kern/init_main.c
r1.120. ive been running this in various places since early 2011.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars