If a receiver returns zero, that means its queue is full and it will
notify us when room is available using qemu_flush_queued_packets().

Take note of that and disable that receiver until it flushes its queue.

This is a first step towards allowing can_receive() handlers to return
true even if no buffer space is available.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Okay, this makes the tap options available on AIX even though there's
no support, but if we want to do it right we should have not compile
the tap code at all on AIX using e.g. CONFIG_TAP.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Enable UFO on the host tap device if supported and allow setting UFO
on virtio-net in the guest.
Signed-off-by: NSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This API allows virtio-net to enable various offload features on a
tap interface - e.g. to tell the host kernel it can pass up partial
checksums to userspace.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

tap_receive_raw() always prepends a vnet header if IFF_VNET_HDR is
enabled.

tap_receive() only prepends when the a header is required but the NIC
doesn't supply one.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Trivial patch to allow supplying a receive_raw function.

A future cleanup should combine this function pointer parameters into a
table.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

In the case where a NIC and backend agree on a packet header format,
this API allows injecting packets which lack the agreed upon header.

We need this for sending our gratuitous ARP.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This allows for the addition of a raw flag, and leaves the way open
for other flags too.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

These lamely named functions allow virtio-net to query whether
IFF_VNET_HDR is enabled on a tap interface and inform the tap code
that virtio-net will supply packets with a vnet header.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This is so as to allow APIs which operate on specific client types
without having to add a function table entry which is only implemented
by a single client type.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This allows people to disable the IFF_VNET_HDR flag, e.g. for debugging
purposes or if they know they may migrate the guest to a machine without
IFF_VNET_HDR support.

It also allows making the lack of IFF_VNET_HDR support an error
condition, e.g. in the case where a guest is being migrated from a host
which does support it.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Re-factor things so that there is only one call site for
net_tap_fd_init().

Two concerns about the QemuOpts usage here - firstly, we set the script
arguments to their default value and, secondly, we set the ifname value
to the name allocated by the kernel if none is supplied. Are we okay
with such things ending up in writeconfig output?
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

For now, we just add an empty header before writing and strip the header
after reading.

We really only want IFF_VNET_HDR when virtio_net is using it, but it
would significantly complicate matters to try and do that. There should
be little or no performance impact with always adding headers.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

In future we will want to prepend a virtio_net header if the NIC didn't
supply one but IFF_VNET_HDR is enabled on the interface. This is most
easily achived by using writev() in all cases.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Making features dependent on the availability of newer versions if_tun.h
is going to get seriously clumsy, so let's just import the definitions
we need. It's only a small handful.

If and when we're comfortable depending on 2.6.30 headers, we can remove
this again.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Add new type for mac addresses.

Add function which sets the qemu default mac address if it finds the mac
address uninitialized (i.e. all zeros).
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

For NICs, net_init_client() returns the index into the NICInfo table.

qemu_opts_foreach() interprets non-zero as an error return an stops
iterating over the options.

So, if you have more than one '-net nic' on the command line, subsequent
'-net' options do not get processed.

Fix this by making net_client_init() only return non-zero if
net_init_client() returns an error.
Reported-by: NPeter Lieven <pl@dlh.net>
Patchworks-ID: 35736
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Now that we have re-factored the packet queue code, we can re-use
it for peer-to-peer also.

Patchworks-ID: 35520
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The packet queue code is fairly standalone, has some complex details and
easily reusable. It makes sense to split it out on its own. This patch
doesn't contain any functional changes.

Patchworks-ID: 35511
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Introduce a 'peer' member to VLANClientState as an alternative
to a vlan. The idea being that packets are transfered directly
from peer clients rather than going through a vlan.

Patchworks-ID: 35516
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Patchworks-ID: 35515
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Allows them to be cleaned up at shutdown.

This is pretty lame, but will eventually go away as we make vlans
the special case.

Patchworks-ID: 35518
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Same as for -net except for:

- only tap, user, vde and socket types are supported
- the vlan parameter is not allowed
- the name parameter is not allowed but the id parameter is
required

Patchworks-ID: 35517
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Patchworks-ID: 35505
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Allow net clients to be created which are not connected to any vlan.

This is needed by Gerd in order to allow adding -device nic, where
the absence of a vlan parameter will not imply vlan=0. Also needed
to allow adding a -netdevice option which doesn't connect the backend
to a vlan.

Patchworks-ID: 35513
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Patchworks-ID: 35507
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Just use the name field instead since we now use the id paramater as
the name, if supplied. Only implication with this change is that if
id is not supplied, the value of the name paramater is used as an
id.

Patchworks-ID: 35512
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Use id= in the same was as the current name= parameter; if both are
specified, id= is used.

Patchworks-ID: 35514
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Needed for e.g. looking up a file descriptor name using
monitor_get_fd() in net_init_tap()

Patchworks-ID: 35509
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This moves the code that depens on slirp under CONFIG_SLIRP again.

Patchworks-ID: 35372
Signed-off-by: NJuan Quintela <quintela@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Now that net_client_init() has no users, kill it off and rename
net_client_init_from_opts().

There is no further need for the old code in net_client_parse() either.
We use qemu_opts_parse() 'firstname' facitity for that. Instead, move
the special handling of the 'vmchannel' type there.

Simplify the vl.c code into merely call net_client_parse() for each
-net command line option and then calling net_init_clients() later
to iterate over the options and create the clients.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

We need net_client_init_from_opts() exported for this
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Here is where we rely on qemu_opts_parse() to handle an empty string.
We could alternatively explicitly handle this here by using
qemu_opts_create() when we're not supplied any parameters, but its
cleaner this way.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Now that we've ported everything over to QemuOpts, we can kill off
all the cruft in net_client_init().

Note, the 'channel' type requires special handling as it uses a
format that QemuOpts can't parse
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Note, not incrementing nb_host_devs in net_init_dump() is intentional.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

The net_vde_init() change is needed because we now pass NULL pointers
instead of empty strings for group/sock if they're not set.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>