qemu: Use a TAP device instead of slirp for networking

With this patch, a persistent TAP device is set up by poky-qemu-ifup,
which is now run before qemu.  The qemu command line now uses the
device that was constructed (rather than the hard-coded tap0) and it
is told not to run any networking scripts.

When qemu shuts down, poky-qemu-ifdown removes the TAP device.

sudo use - sudo is used to run poky-qemu-ifup.  sudo is no longer used
to run qemu, as qemu no longer needs privileges to set up networking.
poky-qemu-ifdown is run without privileges, as you can remove a TAP
device which you own.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>

1 files changed, 4 insertions, 6 deletions

diff --git a/scripts/poky-qemu-ifdown b/scripts/poky-qemu-ifdown
index 2212353118..d9e9e95861 100755
--- a/scripts/poky-qemu-ifdown
+++ b/scripts/poky-qemu-ifdown
@@ -17,11 +17,9 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+TAP=$1
 
-IFCONFIG=`which ifconfig`
-if [ "x$IFCONFIG" = "x" ]; then
-    # better than nothing...
-    IFCONFIG=/sbin/ifconfig
-fi
+TUNCTL=`which tunctl`
+[ "$TUNCTL" = "" ] && TUNCTL=/usr/sbin/tunctl
 
-$IFCONFIG tap0 down
+$TUNCTL -d $TAP