When a dpif passes an odp_msg down to ofproto, and ofproto transforms it
into an ofp_packet_in to send to the controller, until now this always
involved a full copy of the packet inside ofproto. This commit eliminates
this copy by ensuring that there is always enough headroom in the ofpbuf
that holds the odp_msg to replace it by an ofp_packet_in in-place.
From Jean Tourrilhes <jt@hpl.hp.com>, with some revisions.
If the config changes while ovs-vswitchd is not running it is possible
that there could be some vports which are no longer needed but won't
be destroyed when closed because they aren't open. This deletes
unneeded vports at the same time that we clean up unneeded datapaths.
Currently the datapath directly accesses devices through their
Linux functions. Obviously this doesn't work for virtual devices
that are not backed by an actual Linux device. This creates a
new virtual port layer which handles all interaction with devices.
The existing support for Linux devices was then implemented on top
of this layer as two device types. It splits out and renames dp_dev
to internal_dev. There were several places where datapath devices
had to handled in a special manner and this cleans that up by putting
all the special casing in a single location.
This brings over some features that were added to the netdev interface,
most notably the separation between the name and the type. In addition
to being cleaner, this also avoids problems where it is expected that
the local port has the same name as the datapath.
Some versions of GCC warn about this. Always initializing it seems like
the right thing to do, since we "almost always" initialized it before.
Reported-by: Neil McKee <neil.mckee@inmon.com>
The message warning that the device number is wrong for the Open vSwitch
devices could have been clearer.
Thanks to Ben Pfaff for the suggested wording.
When the kernel module isn't loaded, the bridge tries to open all the
possible minor devices, regardless. This change first checks that there
is a major device number for Open vSwitch and only then tries to open the
minor devices.
This change also removes the assumption that there's a default Open vSwitch
major device number, since the kernel module always attempts to get a
dynamic one. Maybe one day we'll have one...
Bug #1179
It was getting to be too confusing to have both netdev_linux_* functions
and linux_netdev_* functions. Rename the latter to make the distinction
more obvious. "rtnetlink" seems to be a fairly good name because that's
what the kernel calls it, so the name will be familiar at least to people
who know about rtnetlink.
This new abstraction layer allows multiple implementations of network
devices in a single running process. This will be useful, for example, to
support network devices that are simulated entirely in the running process
or that communicate with other processes over Unix domain sockets, etc.
The reimplemented tap device support in this commit has not been tested.
At startup, the vswitch needs to delete datapaths that are not configured
by the administrator. Until now this was done by knowing the possible
names of Linux datapaths. This commit cleans up by allowing each
datapath class to enumerate its existing datapaths and their names.
The userspace tools were allowing the name of any internal port to be used
to identify a datapath. This, however, makes it hard to enumerate all the
names by which a datapath can be known, and it was never documented or
intentional behavior, so this commit disables it.
The dpif and netdev code has had various ways to check for changes to
dpifs and netdevs over the course of Open vSwitch development. All of
these have been thus far fairly specific to the Linux implementation. This
commit is the start of a more general API for watching for such changes.
The dpif-related parts seem fairly mature and so they are documented,
the netdev parts will probably need to change somewhat and so they are
not documented yet.
This commit initially introduces only a single datapath implementation,
which is the same as the original one, but it paves the way for
additional implementations, such as the upcoming userspace datapath.
