rtentry and rtrequest

[Yar Tikhiy]

On Thu, Apr 19, 2007 at 06:54:23PM +1000, Alan Garfield wrote:
> On Thu, 2007-04-19 at 11:35 +0400, Yar Tikhiy wrote:
> 
> > > ... and I get these ARP errors.
> > > 
> > > ----
> > > jnet0: <JNet Ethernet System Interface> port 0xa8,0xae-0xaf irq 19 on
> > > acpi0
> > > jnet0: Ethernet address: 00:09:3d:00:00:03
> > > jnet0: jnet_start_locked() called.
> > > jnet0: m == 0.
> > > jnet0: RTM_ADD. 
> > > arplookup 169.254.101.2 failed: could not allocate llinfo
> > > arpresolve: can't allocate route for 169.254.101.2
> > > ----
> > > 
> > > ... whenever I try and send anything.
> > 
> > Did you set the maximum lengths for the output queue and the driver
> > queue in the attach function?
> 
> ----
>         // Configure the structure for the device
>         ifp->if_softc = sc;
>         if_initname(ifp, device_get_name(dev), device_get_unit(dev));
>         
>         // Function pointers 
>         ifp->if_start = jnet_start;
>         ifp->if_ioctl = jnet_ioctl;
>         ifp->if_watchdog = jnet_watchdog;
>         ifp->if_init = jnet_init;
>         
>         // Interface specifics
>         ifp->if_flags = IFF_SIMPLEX;


Try setting those flags to
IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST

I have no direct evidence, but ARP may have trouble operating on
an interface w/o IFF_BROADCAST, as it utilizes broadcasts.  Essentially,
IFF_BROADCAST just means that the interface has a broadcast address,
but there may be some indirect consequences via the routing table.

Anyway, an Ethernet interface ought to have IFF_BROADCAST set on
it because it's a broadcast interface.

>         IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
>         ifp->if_snd.ifq_drv_maxlen = IFQ_MAXLEN;
>         IFQ_SET_READY(&ifp->if_snd); 
>         ifp->if_timer = MAX_TIMEOUT;
> 
>         // Set our fake MAC address
>         bcopy(localMac, sc->enaddr, 6);

Just a style note: the 6 should be ETHER_ADDR_LEN.  We prefer
ETHER_ADDR_LEN to sizeof(...) because sizeof returns size_t, while
an int is sometimes needed.  (int and size_t have different width
on 64-bit architectures.)  ETHER_ADDR_LEN expands to the constant
6, which gets the correct type provided that the function has been
prototyped.

>         // Attach the ethernet interface
>         ether_ifattach(ifp, sc->enaddr);
> 
>         // Reset the mtu
>         ifp->if_mtu = JNET_MTU;
> ----
> 
> I think so. :)
> 
> I beginning to think the ARP issue is a symptom not the cause. The cause
> may well be something is wrong with my initialisation of the output
> queue and my handling of the de-queueing packets. I've looked at many
> if_* drivers sources and they all seem very similar to what I've already
> done.

Please try fixing the interface flags.

Could you also show output from "ifconfig jnetX" and "netstat -rn"
after the interface has been configured (i.e., had IP assigned)?

P.S. Was the name "jnet" inherited from the Linux driver?

-- 
Yar