Perform mmap and poll on PUD character devices

[Roger Pau Monné <roger.pau%entel.upc.edu@localhost>]

Hello,

I'm trying to port blktap2 Linux kernel driver to NetBSD using PUD
(thanks to libpud developed by Vyacheslav Matyushin during this year
SoC). blktap2 is composed of several devices, some of them are block
devices, other are character devices. Now I have to implement a
character device that supports poll and mmap, but character devices
implemented with PUD are not able to declare mmap or poll functions,
is this because some kind of technical limitation, or is it because
nobody has taken the time to implement them?

Thanks, Roger.