[libvirt] [PATCH 3/5] macvtap support for libvirt -- qemu support

[Daniel Veillard]

On Mon, Feb 08, 2010 at 02:37:18PM -0500, Stefan Berger wrote:
> This part adds support for qemu making a macvtap tap device available
> via file descriptor passed to qemu command line. This also attempts to
> tear down the macvtap device when a VM terminates. This includes support
> for attachment and detachment to/from running VM.
> 
> Signed-off-by: Stefan Berger <stefanb at us.ibm.com>
[...]
>  
>  int
> +qemudPhysIfaceConnect(virConnectPtr conn,
> +                      virDomainNetDefPtr net,
> +                      char *linkdev,
> +                      int brmode)
> +{
> +    int rc;
> +#if defined(WITH_MACVTAP)
> +    char *res_ifname = NULL;
> +    int hasBusyDev = 0;
> +
> +    delMacvtapByMACAddress(conn, net->mac, &hasBusyDev);
> +
> +    if (hasBusyDev) {
> +        virReportSystemError(NULL, errno, "%s",
> +                             _("A macvtap with the same MAC address is in use"));
> +        return -1;
> +    }
> +
> +    rc = openMacvtapTap(conn, net->ifname, net->mac, linkdev, brmode,
> +                        &res_ifname);
> +    if (rc > 0) {

  since openMacvtapTap seems to return an fd, rc == 0 sounds a
correct possible return, or am I missing something ?

> +        VIR_FREE(net->ifname);
> +        net->ifname = res_ifname;
> +    }
> +#else
> +    (void)net;
> +    (void)linkdev;
> +    (void)brmode;
> +    qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR,
> +                     "%s", _("No support for macvtap device"));
> +    rc = -1;
> +#endif
> +    return rc;
> +}
> +

  Since qemudPhysIfaceConnect can return -1, 0 or > 0 all with different
semantic, I think a comment describing the function and return value
is in order.

> +int
>  qemudNetworkIfaceConnect(virConnectPtr conn,
>                           struct qemud_driver *driver,
>                           virDomainNetDefPtr net,
> @@ -2520,6 +2558,7 @@ qemuBuildHostNetStr(virConnectPtr conn,
>      switch (net->type) {
>      case VIR_DOMAIN_NET_TYPE_NETWORK:
>      case VIR_DOMAIN_NET_TYPE_BRIDGE:
> +    case VIR_DOMAIN_NET_TYPE_DIRECT:
>          virBufferAddLit(&buf, "tap");
>          virBufferVSprintf(&buf, "%cfd=%s", type_sep, tapfd);
>          type_sep = ',';

  Otherwise looks fine, ACK once resolved :-)

Daniel

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
daniel at veillard.com  | Rpmfind RPM search engine http://rpmfind.net/
http://veillard.com/ | virtualization library  http://libvirt.org/