tools/hotplug, Use udev rules instead of qemu script to setup the bridge.

From: Anthony PERARD <anthony.perard@citrix.com>

This patch adds a second argument to vif-bridge script. It can be "vif"
or "tap". "vif" give the default behavior and "tap" just add the
interface to the found bridge when the action is "add".

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 tools/hotplug/Linux/vif-bridge        |   20 ++++++---
 tools/hotplug/Linux/vif-common.sh     |   70 ++++++++++++++++++++++++---------
 tools/hotplug/Linux/xen-backend.rules |    5 +-
 tools/libxl/libxl.c                   |    6 +-
 4 files changed, 70 insertions(+), 31 deletions(-)

3 files changed, 67 insertions, 28 deletions

diff --git a/tools/hotplug/Linux/vif-bridge b/tools/hotplug/Linux/vif-bridge
index d35144e1e9..82ba676202 100644
--- a/tools/hotplug/Linux/vif-bridge
+++ b/tools/hotplug/Linux/vif-bridge
@@ -81,20 +81,26 @@ fi
 
 case "$command" in
     online)
-	setup_bridge_port "$vif"
-	add_to_bridge "$bridge" "$vif"
+        setup_bridge_port "$dev"
+        add_to_bridge "$bridge" "$dev"
         ;;
 
     offline)
-        do_without_error brctl delif "$bridge" "$vif"
-        do_without_error ifconfig "$vif" down
+        do_without_error brctl delif "$bridge" "$dev"
+        do_without_error ifconfig "$dev" down
+        ;;
+
+    add)
+        add_to_bridge "$bridge" "$dev"
         ;;
 esac
 
-handle_iptable
+if [ "$type_if" = vif ]; then
+    handle_iptable
+fi
 
-log debug "Successful vif-bridge $command for $vif, bridge $bridge."
-if [ "$command" == "online" ]
+log debug "Successful vif-bridge $command for $dev, bridge $bridge."
+if [ "$type_if" = vif -a "$command" = "online" ]
 then
   success
 fi
diff --git a/tools/hotplug/Linux/vif-common.sh b/tools/hotplug/Linux/vif-common.sh
index 44dd342acf..780cc718ab 100644
--- a/tools/hotplug/Linux/vif-common.sh
+++ b/tools/hotplug/Linux/vif-common.sh
@@ -31,12 +31,6 @@ then
   exit 1
 fi
 
-case "$command" in
-    add | remove)
-        exit 0
-        ;;
-esac
-
 
 # Parameters may be read from the environment, the command line arguments, and
 # the store, with overriding in that order.  The environment is given by the
@@ -45,24 +39,62 @@ esac
 
 evalVariables "$@"
 
-ip=${ip:-}
-ip=$(xenstore_read_default "$XENBUS_PATH/ip" "$ip")
+# Older versions of Xen do not pass in the type as an argument,
+# so the default value is vif.
+: ${type_if:=vif}
+
+case "$type_if" in
+    vif)
+        dev=$vif
+        ;;
+    tap)
+        dev=$INTERFACE
+        ;;
+    *)
+        log err "unknown interface type $type_if"
+        exit 1
+        ;;
+esac
 
-# Check presence of compulsory args.
-XENBUS_PATH="${XENBUS_PATH:?}"
-vif="${vif:?}"
+case "$command" in
+    online | offline)
+        test "$type_if" != vif && exit 0
+        ;;
+    add | remove)
+        test "$type_if" != tap && exit 0
+        ;;
+esac
 
 
-vifname=$(xenstore_read_default "$XENBUS_PATH/vifname" "")
-if [ "$vifname" ]
-then
-  if [ "$command" == "online" ] && ! ip link show "$vifname" >&/dev/null
-  then
-    do_or_die ip link set "$vif" name "$vifname"
-  fi
-  vif="$vifname"
+if [ "$type_if" = vif ]; then
+    # Check presence of compulsory args.
+    XENBUS_PATH="${XENBUS_PATH:?}"
+    vif="${vif:?}"
+
+    vifname=$(xenstore_read_default "$XENBUS_PATH/vifname" "")
+    if [ "$vifname" ]
+    then
+        if [ "$command" == "online" ] && ! ip link show "$vifname" >&/dev/null
+        then
+            do_or_die ip link set "$vif" name "$vifname"
+        fi
+        vif="$vifname"
+    fi
+elif [ "$type_if" = tap ]; then
+    # Check presence of compulsory args.
+    : ${INTERFACE:?}
+
+    # Get xenbus_path from device name.
+    # The name is built like that: "tap${domid}.${devid}".
+    dev_=${dev#tap}
+    domid=${dev_%.*}
+    devid=${dev_#*.}
+
+    XENBUS_PATH="/local/domain/0/backend/vif/$domid/$devid"
 fi
 
+ip=${ip:-}
+ip=$(xenstore_read_default "$XENBUS_PATH/ip" "$ip")
 
 frob_iptable()
 {
diff --git a/tools/hotplug/Linux/xen-backend.rules b/tools/hotplug/Linux/xen-backend.rules
index 2d844a15bd..ccbe508f48 100644
--- a/tools/hotplug/Linux/xen-backend.rules
+++ b/tools/hotplug/Linux/xen-backend.rules
@@ -2,10 +2,11 @@ SUBSYSTEM=="xen-backend", KERNEL=="tap*", RUN+="/etc/xen/scripts/blktap $env{ACT
 SUBSYSTEM=="xen-backend", KERNEL=="vbd*", RUN+="/etc/xen/scripts/block $env{ACTION}"
 SUBSYSTEM=="xen-backend", KERNEL=="vtpm*", RUN+="/etc/xen/scripts/vtpm $env{ACTION}"
 SUBSYSTEM=="xen-backend", KERNEL=="vif2-*", RUN+="/etc/xen/scripts/vif2 $env{ACTION}"
-SUBSYSTEM=="xen-backend", KERNEL=="vif-*", ACTION=="online", RUN+="/etc/xen/scripts/vif-setup online"
-SUBSYSTEM=="xen-backend", KERNEL=="vif-*", ACTION=="offline", RUN+="/etc/xen/scripts/vif-setup offline"
+SUBSYSTEM=="xen-backend", KERNEL=="vif-*", ACTION=="online", RUN+="/etc/xen/scripts/vif-setup online type_if=vif"
+SUBSYSTEM=="xen-backend", KERNEL=="vif-*", ACTION=="offline", RUN+="/etc/xen/scripts/vif-setup offline type_if=vif"
 SUBSYSTEM=="xen-backend", KERNEL=="vscsi*", RUN+="/etc/xen/scripts/vscsi $env{ACTION}"
 SUBSYSTEM=="xen-backend", ACTION=="remove", RUN+="/etc/xen/scripts/xen-hotplug-cleanup"
 KERNEL=="evtchn", NAME="xen/%k"
 KERNEL=="blktap[0-9]*", NAME="xen/%k"
 KERNEL=="pci_iomul", NAME="xen/%k"
+SUBSYSTEM=="net", KERNEL=="tap*", ACTION=="add", RUN+="/etc/xen/scripts/vif-setup $env{ACTION} type_if=tap"