Re: [Qemu-devel] [PATCH] net: Allow specifying ifname for qemu-bridge-helper

[Mike Lovell <mike@dev-zero.net>]

On 10/12/2012 12:49 AM, Mike Lovell wrote:
> This makes a few changes to allow ifname to be specified when using
> qemu-bridge-helper with both the bridge and tap network interfaces. It adds
> the --ifname option to qemu-bridge-helper, removes the restriction that ifname
> cannot be specified with helper for the tap interface, and adds logic to
> specify the --ifname option when exec'ing the helper.
>
> Signed-off-by: Mike Lovell <mike@dev-zero.net>
> ---
>
> This feature was originally requested by Mario De Chenno on the qemu-devel
> mailing list. Seems pretty simple and figured it was something I could throw
> together pretty quickly. I have tested the following combinations of invoking
> qemu (where qbr is qemu-bridge-helper)
>
> qemu-system-x86_64 -net nic -net tap,helper="qbr --br=test1"
> qemu-system-x86_64 -net nic -net tap,helper="qbr --br=test1",ifname=vm1
> qemu-system-x86_64 -net nic -net tap,helper=qbr
> qemu-system-x86_64 -net nic -net tap,helper=qbr,ifname=vm1
> qemu-system-x86_64 -net nic -net bridge,helper=qbr
> qemu-system-x86_64 -net nic -net bridge,helper=qbr,ifname=vm1
> qemu-system-x86_64 -net nic -net bridge,helper=qbr,ifname=vm1,br=test1
> qemu-system-x86_64 -net nic -net bridge,helper=qbr,br=test1

I realized there were a couple more cases to check. I also tested the 
following.

qemu-system-x86_64 -net nic -net tap,helper="qbr --ifname=vm1"
qemu-system-x86_64 -net nic -net tap,helper="qbr --br=test1 --ifname=vm1"
qemu-system-x86_64 -net nic -net tap,helper="qbr --ifname=vm1",ifname=foo
qemu-system-x86_64 -net nic -net tap,helper="qbr --br=test1 
--ifname=vm1",ifname=foo

In the last two cases, the --ifname specified in the helper option (in 
this case, vm1) is used over the tap ifname option (in this case, foo).

mike