[libvirt] [PATCH 7/7] Add support for attaching network/bridge NICs in QEMU driver

[Daniel Veillard]

On Wed, Jul 22, 2009 at 10:57:36PM +0100, Mark McLoughlin wrote:
> In order to hotplug a network/bridge backed NIC, we need to first create
> the tap file descriptor, add the tap interface to the bridge and then
> pass the file descriptor to the qemu process using the 'getfd' monitor
> command.
> 
> Once the tapfd has been accepted, we create the network backend using
> host_net_add, supplying the name assigned to the tapfd. If this fails,
> we need to close the tapfd in qemu using the 'closefd' monitor command.
> 
> * src/qemu_driver.c: add support for tapfd based hotplug in
>   qemudDomainAttachNetDevice()
[...]
> +    if (tapfd != -1) {
> +        if (virAsprintf(&tapfd_name, "fd-%s", net->hostnet_name) < 0)
> +            goto no_memory;
> +
> +        if (virAsprintf(&tapfd_close, "closefd %s", tapfd_name) < 0)
> +            goto no_memory;

[...]
>  
> +try_tapfd_close:
> +    VIR_FREE(reply);
> +
> +    if (tapfd_close) {
> +        if (qemudMonitorCommand(vm, tapfd_close, &reply) < 0)
> +            VIR_WARN(_("Failed to close tapfd with '%s'\n"), tapfd_close);
> +        else
> +            VIR_DEBUG("%s: closefd: %s\n", vm->def->name, reply);
> +    }
> +    goto cleanup;

  This makes sense except I didn't expect tapfd_close which seems used
  only in an error path to be allocated on the main branch (assuming a
  tapfd).

  Otherwise looks clean, ACK

Daniel

-- 
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