network interface in userland?

What needs to be done to support network interfaces in
userland?

I am mostly curious about this for developing and testing
without 
rebooting kernels.

If this has been discussed before, please point me to it.

By the way, I have a USB-based internal wireless interface I
want 
supported:

	port 6 addr 3: high speed, power 500 mA, config 1, 
	RTL8187B_WLAN_Adapter(0x8197), Realtek(0x0bda), rev 2.00,
serial 
	00e04c000001

On Fri Dec 14 2007 at 10:56:14 -0600, reedreedmedia.net wrote:
> What needs to be done to support network interfaces in
userland?
> 
> I am mostly curious about this for developing and
testing without 
> rebooting kernels.
> 
> If this has been discussed before, please point me to
it.
> 
> By the way, I have a USB-based internal wireless
interface I want 
> supported:

I haven't really given it thought, but some ramblings:

You need to access the hardware somehow.  For this you
probably need a
userspace "port" of bus_space and bus_dma,
although I don't know how
exactly that would work.  You also need to tap into the
interrupts,
for which polling might be a better (easier) solution.

You should be able to hack interfacing with the kernel
networking stack
with tap(4).  Not really perfect, but should work.

For wireless need to run net80211 in userspace also.

So, not really "compile & go" for the time
being.

-- 
Antti Kantee <pookaiki.fi>                     Of course
he runs NetBSD
http://www.iki.fi/pooka/
                         http://www.NetBSD.org/
    "la qualité la plus indispensable du cuisinier est
l'exactitude"

> You should be able to hack interfacing with the kernel
networking
> stack with tap(4).  Not really perfect, but should
work.

Only if the interface is sufficiently Ethernet-like.

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On Fri, Dec 14, 2007 at 07:07:40PM +0200, Antti Kantee
wrote:
> On Fri Dec 14 2007 at 10:56:14 -0600, reedreedmedia.net wrote:
> > By the way, I have a USB-based internal wireless
interface I want 
> > supported:
> 
> You need to access the hardware somehow.  For this you
probably need a
> userspace "port" of bus_space and bus_dma,
although I don't know how
> exactly that would work.  You also need to tap into the
interrupts,
> for which polling might be a better (easier) solution.

libusb provides that specifically for USB devices. That
doesn't solve
the problem of having a 802.11 stack, but at least the
hardware access
is easy.

Joerg

> I am mostly curious about this for developing and
testing without
> rebooting kernels.

If what you need is trying a new driver without reboot, LKM
*should
be* the way to go.

(I say *should be* because I have never tried that. 

Masao

DragonflyBSD has done some kernel 'virtualisation' in
userland.
Meaning running kernel and network interface drivers in
userland,
maybe take a look at that.
It would be nice to have that ability in FreeBSD/NetBSD
too.

On Dec 15, 2007 1:06 PM, Masao Uebayashi <uebayasigmail.com> wrote:
> > I am mostly curious about this for developing and
testing without
> > rebooting kernels.
>
> If what you need is trying a new driver without reboot,
LKM *should
> be* the way to go.
>
> (I say *should be* because I have never tried that.

>
> Masao
>