libs/light: pass some infos to qemu

Pass bridge name to qemu as command line option
When starting qemu, set an environnement variable XEN_DOMAIN_ID,
to be used by qemu helper scripts
The only functional difference of using the br parameter is that the
bridge name gets passed to the QEMU script.
NetBSD doesn't have the ioctl to rename network interfaces implemented, and
thus cannot rename the interface from tapX to vifX.Y-emu. Only qemu knowns
the tap interface name, so we need to use the qemu script from qemu itself.

Signed-off-by: Manuel Bouyer <bouyer@netbsd.org>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>

diff --git a/tools/libs/light/libxl_dm.c b/tools/libs/light/libxl_dm.c
index 45a0504a2ec585158d4a58ac38f548575edc45a5..291dee9b3f4d39032162dd74001c2d1dc9d464f9 100644 (file)
--- a/tools/libs/light/libxl_dm.c
+++ b/tools/libs/light/libxl_dm.c
@@ -761,6 +761,8 @@ static int libxl__build_device_model_args_old(libxl__gc *gc,
         int nr_set_cpus = 0;
         char *s;
 
+        flexarray_append_pair(dm_envs, "XEN_DOMAIN_ID", GCSPRINTF("%d", domid));
+
         if (b_info->kernel) {
             LOGD(ERROR, domid, "HVM direct kernel boot is not supported by "
                  "qemu-xen-traditional");
@@ -1547,8 +1549,10 @@ static int libxl__build_device_model_args_new(libxl__gc *gc,
                 flexarray_append(dm_args, "-netdev");
                 flexarray_append(dm_args,
                                  GCSPRINTF("type=tap,id=net%d,ifname=%s,"
+                                           "br=%s,"
                                            "script=%s,downscript=%s",
                                            nics[i].devid, ifname,
+                                           nics[i].bridge,
                                            libxl_tapif_script(gc),
                                            libxl_tapif_script(gc)));
 
@@ -1825,6 +1829,8 @@ static int libxl__build_device_model_args_new(libxl__gc *gc,
     flexarray_append(dm_args, GCSPRINTF("%"PRId64, ram_size));
 
     if (b_info->type == LIBXL_DOMAIN_TYPE_HVM) {
+        flexarray_append_pair(dm_envs, "XEN_DOMAIN_ID", GCSPRINTF("%d", guest_domid));
+
         if (b_info->u.hvm.hdtype == LIBXL_HDTYPE_AHCI)
             flexarray_append_pair(dm_args, "-device", "ahci,id=ahci0");
         for (i = 0; i < num_disks; i++) {