body of reaper(), right before the call to uvm_exit(). cpu_wait() must
be done before uvm_exit() because the resources it frees might be located
in the PCB.
which use uvm_vslock() should now test the return value. If it's not
KERN_SUCCESS, wiring the pages failed, so the operation which is using
uvm_vslock() should error out.
XXX We currently just EFAULT a failed uvm_vslock(). We may want to do
more about translating error codes in the future.
vslocking here?! copyout() on its own seems to suffice just about everwhere
else, and it's not like the process is going to exit; it's in a system
call!
count is 0, wait for use count to drain before finishing the close.
This is necessary in order for multiple processes to safely share file
descriptor tables.
thorpej