[ovs-dev] [#8024 5/7] Don't overload IP TOS with the frag matching bits.

[Ben Pfaff]

On Mon, Nov 07, 2011 at 10:33:08AM -0800, Justin Pettit wrote:
> This will be useful later when we add support for matching the ECN bits
> within the TOS field.
> 
> Signed-off-by: Justin Pettit <jpettit at nicira.com>

kernel
------

Do you plan to use the top 6 bits of ip.frag for something later on?
If not, I think we can drop all the bitwise manipulation that assumes
that something might be in those bits, get rid of OVS_FRAG_TYPE_MASK,
etc.

#defining OVS_FRAG_TYPE_MASK as INET_ECN_MASK makes a lot less sense
now, anyway.

Dropping parse_tos_frag() dropped validation of the ipv4_tos and
ipv4_frag members from flow_from_nlattrs().  Probably it's good to
still validate them.

user
----

The tos field isn't bitwise maskable so we could use a FWW_* bit for
it.  (It might not be worth the churn though.)

Like the kernel, the frag field uses all the bits so it's probably
worthwhile to drop most of the bitwise operations there too.

In ofputil_normalize_rule(), I think I'd just rename MAY_TOS_FRAG to
MAY_IPVx (or similar) instead of breaking it apart, since they always
go together.

Thanks,

Ben.