[libvirt] [PATCH v3 05/36] network: use 'bridge' as actual type instead of 'network'

[Cole Robinson]

On 3/19/19 8:46 AM, Daniel P. Berrangé wrote:
> Ports allocated on virtual networks with type=nat|route|open all get
> given an actual type of 'network'.
> 
> Only ports in networks with type=bridge use an actual type of 'bridge'.
> 
> This distinction makes little sense since the virtualization drivers
> will treat both actual types in exactly the same way, as they're all
> just bridge devices a VM needs to be connected to.
> 
> This doesn't affect user visible XML since the "actual" device XML
> is internal only, but we need code to convert the data upgrades.
> 
> Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
> ---
>  src/network/bridge_driver.c | 20 ++++++++++++--------
>  1 file changed, 12 insertions(+), 8 deletions(-)
> 

Conceptually this makes sense. I wonder what the original motivation for
the differentiation was. This also makes me wish there was a separate
enum for the internal actual->type field, it would make ambiguous code
much more readable

> diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
> index 4770dd1e4e..40122612c8 100644
> --- a/src/network/bridge_driver.c
> +++ b/src/network/bridge_driver.c
> @@ -4454,11 +4454,7 @@ networkAllocateActualDevice(virNetworkPtr net,
>      case VIR_NETWORK_FORWARD_NAT:
>      case VIR_NETWORK_FORWARD_ROUTE:
>      case VIR_NETWORK_FORWARD_OPEN:
> -        /* for these forward types, the actual net type really *is*
> -         * NETWORK; we just keep the info from the portgroup in
> -         * iface->data.network.actual
> -         */
> -        iface->data.network.actual->type = VIR_DOMAIN_NET_TYPE_NETWORK;
> +        iface->data.network.actual->type = VIR_DOMAIN_NET_TYPE_BRIDGE;
>  
>          /* we also store the bridge device and macTableManager settings
>           * in iface->data.network.actual->data.bridge for later use
> @@ -4832,6 +4828,15 @@ networkNotifyActualDevice(virNetworkPtr net,
>                      netdef->bridge) < 0))
>              goto error;
>  
> +    /* Older libvirtd uses actualType==network, but we now
> +     * just use actualType==bridge, as nothing needs to
> +     * distinguish the two cases, and this simplifies virt
> +     * drive code */
> +    if (actualType == VIR_DOMAIN_NET_TYPE_NETWORK) {
> +        iface->data.network.actual->type = VIR_DOMAIN_NET_TYPE_BRIDGE;
> +        actualType = VIR_DOMAIN_NET_TYPE_BRIDGE;
> +    }
> +

Why do this here and not at the status XML parse time? This code path is
only called on reconnected devices correct? So that should always be
hitting the status XML parser too AFAICT. That would make it easier to
audit any TYPE_NETWORK paths in the status parser as well

qemu_driver.c processNicRxFilterChangedEvent also has a

if (virDomainNetGetActualType(def) == VIR_DOMAIN_NET_TYPE_NETWORK) {

which looks sketchy after this. And it's involving bandwidth stuff so it
may affect the previous patch too.

- Cole