Martin Husemann wrote:
> In my view the question is: is there any chance, this VFS op routine is 
> going to be called outside the LKM unload context. If the answer is true,
> then of course the right thing to do is create that VFS op routine.
> 
> If we can't come up with an example for this, then I would opt for the LKM
> unload cleanup function - but thats just a matter of taste.

The routine would be needed whenever vfs_detach() is needed. vfs_detach()
is currently only called from kern_lkm.c:_lkm_vfs(), though.

There is little difference in implementing the cleanup as "independant"
function callable from outside or a VFS op routine.

But as it's not a LKM cleanup function per se, I'd prefer adding it as
a VFS op. This would make it possible to do the global fs cleanup
in vfs_detach() where it logically belongs, and avoid silly
pastos in respective syssrc/sys/lkm/vfs/*/lkminit_vfs.c.

Since we broke VFS LKM ABI at least once between 1.4 and upcoming
1.5, I don't think breaking it once more would cause (m)any
additional problems. Furthermore, this particular change would
only bite people who attempt to _unload_ "older" VFS LKM (reboots
are fine).

Jaromir
-- 
Jaromir Dolecek <jdolecek@NetBSD.org>      http://www.ics.muni.cz/~dolecek/
@@@@  Wanna a real operating system ? Go and get NetBSD, damn!  @@@@