From 18d65d225831995f9163e718ad57e839758314e0 Mon Sep 17 00:00:00 2001 From: Thomas Huth Date: Mon, 15 Jan 2018 20:50:55 +0100 Subject: net: Allow hubports to connect to other netdevs QEMU can emulate hubs to connect NICs and netdevs. This is currently primarily used for the mis-named 'vlan' feature of the networking subsystem. Now the 'vlan' feature has been marked as deprecated, since its name is rather confusing and the users often rather mis-configure their network when trying to use it. But while the 'vlan' parameter should be removed at one point in time, the basic idea of emulating a hub in QEMU is still good: It's useful for bundling up the output of multiple NICs into one single l2tp netdev for example. Now to be able to use the hubport feature without 'vlan's, there is one missing piece: The possibility to connect a hubport to a netdev, too. This patch adds this possibility by introducing a new "netdev=..." parameter to the hubports. To bundle up the output of multiple NICs into one socket netdev, you can now run QEMU with these parameters for example: qemu-system-ppc64 ... -netdev socket,id=s1,connect=:11122 \ -netdev hubport,hubid=1,id=h1,netdev=s1 \ -netdev hubport,hubid=1,id=h2 -device e1000,netdev=h2 \ -netdev hubport,hubid=1,id=h3 -device virtio-net-pci,netdev=h3 For using the socket netdev, you have got to start another QEMU as the receiving side first, for example with network dumping enabled: qemu-system-x86_64 -M isapc -netdev socket,id=s0,listen=:11122 \ -device ne2k_isa,netdev=s0 \ -object filter-dump,id=f1,netdev=s0,file=/tmp/dump.dat After the ppc64 guest tried to boot from both NICs, you can see in the dump file (using Wireshark, for example), that the output of both NICs (the e1000 and the virtio-net-pci) has been successfully transfered via the socket netdev in this case. Suggested-by: Paolo Bonzini Signed-off-by: Thomas Huth Signed-off-by: Jason Wang --- net/net.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/net.c') diff --git a/net/net.c b/net/net.c index 2b81c93193..e1569e7d89 100644 --- a/net/net.c +++ b/net/net.c @@ -1063,7 +1063,7 @@ static int net_client_init1(const void *object, bool is_netdev, Error **errp) /* Do not add to a vlan if it's a nic with a netdev= parameter. */ if (netdev->type != NET_CLIENT_DRIVER_NIC || !opts->u.nic.has_netdev) { - peer = net_hub_add_port(net->has_vlan ? net->vlan : 0, NULL); + peer = net_hub_add_port(net->has_vlan ? net->vlan : 0, NULL, NULL); } if (net->has_vlan && !vlan_warned) { -- cgit v1.2.3