devd limitations / automounting removable storage

[M. Warner Losh]

In message: <20030918003556.GA1025 at saboteur.dek.spc.org>
            Bruce M Simpson <bms at spc.org> writes:
: On Wed, Sep 17, 2003 at 08:18:49PM -0400, Jeff Roberson wrote:
: > On Wed, 17 Sep 2003, John-Mark Gurney wrote:
: > > I was thinking about a more generic event posting mechanism, where
: > > modules can register to receive notifications when events came in.
: > 
: > Please use kqueue.  We should have 1 eventing mechanism in the kernel.
: 
: Right now, the way devd/devctl works, it simply polls that device for changes.

No.  devctl gets an event queued to its read channel.  devd then reads
it.  That's different than polling for changes.

: Interesting. Are you suggesting we ditch /dev/devctl and define event
: filters instead inside NEWBUS? Assuming kqueue can be made to play with
: SMP and that we can push Giant out of it this might not be such a bad idea.

kqueue can report events. It can't transport arbitrary data, which is
what is needed here.

Warner