Re: [libvirt] [PATCH 0/5 v3] Interface pools and passthrough mode

On Wed, Dec 14, 2011 at 10:47:23AM +0000, Shradha Shah wrote: > Interface Pools and Passthrough mode: > > Current Method: > The passthrough mode uses a macvtap direct connection to connect each > guest to the network. The physical interface to be used is picked from > among those listed in <interface> sub elements of the <forward> element. > > The current specification for <forward> extends to allow 0 or more > <interface> sub-elements: > Example: > <forward mode='passthrough' dev='eth10'/> > <interface dev='eth10'/> > <interface dev='eth12'/> > <interface dev='eth18'/> > <interface dev='eth20'/> > </forward> > > However with an ethernet card with 64 VF's or more, the above method > gets tedious on the system. > > On the other hand, just parameterizing a string (eth%d) is inadequate, > eg, when there are multiple non-contiguous ranges. > > Proposed Method: > The 4 patches provided: > > i) Introduce a new element 'pf' to implicitly create an interface pool > of all the Virtual Functions attached to the specified Physical > Function. > ii) Modify the networkAllocateActualDevice, networkNotifyActualDevice > and networkReleaseActualDevice API to use the above mentioned interface > pool in the passthrough mode. > iii) Allow virsh net-dumpxml to use an option --inactive to > differentiate between explicit and implicit interface pools > > Hence Libvirt will now support both the methods mentioned below: > > * Explicit interface list. App inputs: > > <forward mode='passthrough'> > <interface dev='eth10'/> > <interface dev='eth11'/> > <interface dev='eth12'/> > <interface dev='eth13'/> > </forward> > > libvirt does not change XML > > * Automatically interface list from PF. App inputs: > > <forward mode='passthrough'> > <pf dev='eth0'/> > </forward> > > libvirt expands XML to be > > <forward mode='passthrough'> > <pf dev='eth0'/> > <interface dev='eth10'/> > <interface dev='eth11'/> > <interface dev='eth12'/> > <interface dev='eth13'/> > </forward> > > In the above case we need to differentiate between the implicit and > explicit interface pool, which can be done by comparing the dumpxml from > active and inactive domains. > This will need the addition of the flag VIR_NETWORK_XML_INACTIVE to > virNetworkGetXMLDesc(). > > This patch series supports the use of option --inactive with virsh > net-dumpxml. The design and code all looks good to me. Just some fairly minor code & style bugs to deal with, which I've replied to inline. Regards, Daniel