For a long time, Open vSwitch has "normalized" OpenFlow 1.0 flows in a
funny way: it tries to change fields that are wildcarded into fields
that are exact-match. For example, the normalize_match() function
knows that if dl_type is wildcarded, then all of the L3 and L4 fields
will always be extracted as 0, so it sets those fields to exact-match
and their values to 0.
The reason for this was originally that exact-match flows were much
cheaper for Open vSwitch to implement, because they could be implemented
with a hash table, whereas other kinds of flows had to be implemented
with an expensive linear search. But these days Open vSwitch has a
smarter classifier in which wildcarded flows have minimal cost. Also,
it is no longer possible for OpenFlow 1.0 to specify truly exact-match
flows, because Open vSwitch supports fields for which OpenFlow 1.0
cannot specify values and therefore will always be wildcarded.
Now, it no longer makes sense to do this transformation, so this commit
removes it. Presumably, this will be less surprising for users.
Reviewed-by: Simon Horman <horms@verge.net.au>
The normalize_match() function does more work than really needed. It goes
to some trouble to zero out fields that are wildcarded. This is not
necessary, because cls_rule_from_match() will take care of it later.
Also make normalize_match() private to ofp-util.c, since it has no other
users now and I don't expect more later.
Reviewed-by: Simon Horman <horms@verge.net.au>
This implements basic multiple table support in ofproto and supporting
libraries and utilities. The design is the same as the one that has been
on the Open vSwitch "wdp" branch for a long time. There is no support for
multiple tables in the software switch implementation (ofproto-dpif), only
a set of hooks for other switch implementations to use.
To allow controllers to add flows in a particular table, Open vSwitch adds
an OpenFlow 1.0 extension called NXT_FLOW_MOD_TABLE_ID.
I looked at almost every uint<N>_t in the tree to determine whether it was
really in network byte order, and converted the ones that were.
The only remaining ones, modulo my mistakes, are in openflow.h. I'm not
sure whether we should convert those, because there might be some value
in remaining close to upstream for this header.
The "tun_id_from_cookie" OpenFlow extension predated NXM and supports only
a fraction of its features. Nothing (at Nicira, anyway) uses it any
longer. Support for it had been broken since January and it took until a
few days ago for anyone to complain, so it cannot be too important. This
commit removes it.
Back in 2008 or so, I introduced this extension as a way to provide
information about switch status to the new "switch UI" program. Since
then, the switch UI program has been removed and the important information
that was provided by the switch status extension is now available in the
database, so we might as well get rid of this extension, and that is what
this commit does.
This function will see more use later in this series. This commit just
starts using it to make ofp-print output entirely consistent for
OFPST_FLOW and NXST_FLOW replies.
One of the goals for Open vSwitch is to decouple kernel and userspace
software, so that either one can be upgraded or rolled back independent of
the other. To do this in full generality, it must be possible to change
the kernel's idea of the flow key separately from the userspace version.
In turn, that means that flow keys must become variable-length. This
commit makes that change using Netlink attribute sequences.
This commit does not actually make userspace flexible enough to handle
changes in the kernel flow key structure, because userspace doesn't yet
have enough information to do that intelligently. Upcoming commits will
fix that.
Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>
This fixes OpenFlow 1.0 flow stats reporting of flows added via NXM.
I noticed this problem while implementing 64-bit tunnel IDs, hence the
positioning. The following commit adds a test.
Acked-by: Jesse Gross <jesse@nicira.com>
These will be useful for adding Nicira Extended Match support to ovs-ofctl.
This commit makes ofproto use the new flow_mod abstraction, but not the
new flow and aggregate stats abstraction. The latter takes a bit more
infrastructure that I haven't finished yet.
Open vSwitch contains a few different chunks of code that need to decode
an OpenFlow message to determine its type and then validate that it is
long enough. Until now, the code for doing this has been more or less
scattered across the tree. Whenever a new piece of code needed to do this,
it generally needed to reimplement at least part of it.
This commit centralizes all of that work into a single function,
ofputil_decode_msg_type(), and helper functions, and converts all of the
code that was decoding messages by hand to use the new function.
This reduces code duplication, by eliminating a function that translates
from "struct flow" to "struct ofp_match" in favor of the existing function
ofputil_cls_rule_to_match(). It also allows the caller to specify the
desired priority (as part of the cls_rule).
Originally, wildcards were just the OpenFlow OFPFW_* bits. Then, when
OpenFlow added CIDR masks for IP addresses, struct flow_wildcards was born
with additional members for those masks, derived from the wildcard bits.
Then, when OVS added support for tunnels, we added another bit
NXFW_TUN_ID that coexisted with the OFPFW_*. Later we added even more bits
that do not appear in the OpenFlow 1.0 match structure at all. This had
become really confusing, and the difficulties were especially visible in
the long list of invariants in comments on struct flow_wildcards.
This commit cleanly separates the OpenFlow 1.0 wildcard bits from the
bits used inside Open vSwitch, by defining a new set of bits that are
used only internally to Open vSwitch and converting to and from those
wildcard bits at the point where data comes off or goes onto the wire.
It also moves those functions into ofp-util.[ch] since they are only for
dealing with OpenFlow wire protocol now.
The 'xid' in an ofp_header is not interpreted by the receiver but only by
the sender, so it need not be in any particular byte order. OVS used to
try to take advantage of this to avoid host/network byte order conversions
for this field. Older code in OVS, therefore, treats xid as being in host
byte order. However, as time went on, I forgot that I had introduced this
trick, and so newer code treats xid as being in network byte order.
This commit fixes up the situation by consistently treating xid as being
in network byte order. I think that this will be less surprising and
easier to remember in the future.
This doesn't fix any actual bugs except that some log messages would have
printed xids in the wrong byte order.
The upcoming support for actions on registers will require the flow to
validate actions, so this commit adds the parameter in advance. It is
not yet used.
An upcoming commit will require the flow to be passed in as part of
OpenFlow action validation, but handle_packet_out() has until now been
structured to make this difficult. This commit refactors it to better
suit this purpose.
This breaks this OpenFlow handler into two parts, one responsible
for parsing and constructing OpenFlow messages and one that works
with the flow table. The latter will be reused in a later commit
that implements the Nicira Extended Match flexible flow match
extension.
When userspace and the kernel were using the same structure for flows,
flow_t was a useful way to indicate that a structure was really a userspace
flow instead of a kernel one, but now it's better to just write "struct
flow" for consistency, since OVS doesn't use typedefs for structs
elsewhere.
Acked-by: Jesse Gross <jesse@nicira.com>
Open vSwitch has always "normalized" flows, that is, zeroed out fields that
are wildcarded or that otherwise cannot affect whether a packet actually
matches the flow. But until now it has done so silently, which prevents
the authors of controllers from learning what is happening and makes it
less likely that they will update code on their end. This commit makes
OVS log when normalization changes a flow.
Suggested by partner.
ovs-vswitchd doesn't declare its QoS capabilities in the database yet,
so the controller has to know what they are. We can add that later.
The linux-htb QoS class has been tested to the extent that I can see that
it sets up the queues I expect when I run "tc qdisc show" and "tc class
show". I haven't tested that the effects on flows are what we expect them
to be. I am sure that there will be problems in that area that we will
have to fix.
The main purpose of the vconn code is to ship OpenFlow messages across
network connections. Over time a large number of utility functions related
to OpenFlow messages have also crept into vconn.c, but that's really
logically separate. This commit breaks those functions out into a new
file.
