Re: [Qemu-devel] [PATCH] net: Add interface to bridge when SIOCBRADDIF isn't available

[Fabien Chouteau <chouteau@adacore.com>]

On 07/12/2012 03:24 PM, Corey Bryant wrote:
> The bridge helper uses the SIOCBRADDIF ioctl to add an inteface to
> a bridge.  SIOCBRADDIF is not available on old Linux versions.  This
> patch adds support to use the SIOCDEVPRIVATE ioctl with BRCTL_ADD_IF
> if SIOCBRADDIF is not available.
> 

I don't have time to test it, but the code looks good and in compiles.

Acked-by: Fabien Chouteau <chouteau@adacore.com>

> Reported-by: Fabien Chouteau <chouteau@adacore.com>
> Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
> ---
>  qemu-bridge-helper.c |   24 +++++++++++++++++++++---
>  1 file changed, 21 insertions(+), 3 deletions(-)
> 
> diff --git a/qemu-bridge-helper.c b/qemu-bridge-helper.c
> index aec5008..652eec9 100644
> --- a/qemu-bridge-helper.c
> +++ b/qemu-bridge-helper.c
> @@ -35,6 +35,10 @@
>  
>  #include <linux/sockios.h>
>  
> +#ifndef SIOCBRADDIF
> +#include <linux/if_bridge.h>
> +#endif
> +
>  #include "qemu-queue.h"
>  
>  #include "net/tap-linux.h"
> @@ -221,6 +225,10 @@ static int drop_privileges(void)
>  int main(int argc, char **argv)
>  {
>      struct ifreq ifr;
> +#ifndef SIOCBRADDIF
> +    unsigned long ifargs[4];
> +#endif
> +    int ifindex;
>      int fd, ctlfd, unixfd = -1;
>      int use_vnet = 0;
>      int mtu;
> @@ -361,9 +369,19 @@ int main(int argc, char **argv)
>  
>      /* add the interface to the bridge */
>      prep_ifreq(&ifr, bridge);
> -    ifr.ifr_ifindex = if_nametoindex(iface);
> -
> -    if (ioctl(ctlfd, SIOCBRADDIF, &ifr) == -1) {
> +    ifindex = if_nametoindex(iface);
> +#ifndef SIOCBRADDIF
> +    ifargs[0] = BRCTL_ADD_IF;
> +    ifargs[1] = ifindex;
> +    ifargs[2] = 0;
> +    ifargs[3] = 0;
> +    ifr.ifr_data = (void *)ifargs;
> +    ret = ioctl(ctlfd, SIOCDEVPRIVATE, &ifr);
> +#else
> +    ifr.ifr_ifindex = ifindex;
> +    ret = ioctl(ctlfd, SIOCBRADDIF, &ifr);
> +#endif
> +    if (ret == -1) {
>          fprintf(stderr, "failed to add interface `%s' to bridge `%s': %s\n",
>                  iface, bridge, strerror(errno));
>          ret = EXIT_FAILURE;
> 


-- 
Fabien Chouteau