[PATCH] Updated 802.1p/q patch

[Bruce M Simpson]

Hi,

I have tested my 802.1p input patch with vlans configured. So far so good.

It is now available from: 
http://people.FreeBSD.org/~bms/dump/latest-8021p.diff

This updated patch moves the 802.1q encapsulation into if_ethersubr.c, 
allowing
M_VLANTAG to be passed up and down the stack for 802.1p priority.
I would greatly appreciate wider testing before it is committed.

I've noticed that vlan(4) will not put a parent interface into PROMISC
if the vlanhwtag capability exists but is disabled.

If the main non-vlan input path receives datagrams destined for
a layer 3 address configured on a vlan interface, the netinet stack
will quite reasonably try to reply on the vlan interface unless
net.inet.ip.check_interface is set to 1; something to be aware of.

If vlan(4) gets an mbuf which has already been tagged with M_VLANTAG
from higher up in the stack, it *should* ignore the vlan id by overwriting
it, and using the priority field already assigned to it, so that ALTQ or
PF can do its magic. This new patch should do this.

The Ethernet code will not use 802.1p by default unless it came from
higher up (by way of M_VLANTAG passed to a driver); we should insert
the 802.1p tag in the situation where we got an M_VLANTAG from further
up without a vlan(4) instance being involved. The new patch should do this.

We should also make sure the CFI bit is always cleared in bridging
situations as it has special meaning for token ring and FDDI.

What has not been tested or considered is the situation where we have
nested VLANs. At least one individual has asked about this feature. At
the moment, I'd suggest that only Netgraph potentially deals with this
rather than the main network stack.

Regards,
BMS