[Kimchi-devel] [PATCH] Add OVS bridges recognition support

[Lucio Correia]

In some distributions, i.e. Fedora, the directories "bridge"
and "brif" are not created for OVS bridges, and they are the
method Kimchi uses to detect bridges.

This patch fixes that by recognizing OVS bridges through OVS
commands, allowing networks to be created using OVS bridges
in those distributions.

Signed-off-by: Lucio Correia <luciojhc at linux.vnet.ibm.com>
---
 src/wok/plugins/kimchi/model/networks.py |  2 +-
 src/wok/plugins/kimchi/netinfo.py        | 55 ++++++++++++++++++++++++++++----
 2 files changed, 50 insertions(+), 7 deletions(-)

diff --git a/src/wok/plugins/kimchi/model/networks.py b/src/wok/plugins/kimchi/model/networks.py
index 71ea595..d78b88e 100644
--- a/src/wok/plugins/kimchi/model/networks.py
+++ b/src/wok/plugins/kimchi/model/networks.py
@@ -167,7 +167,7 @@ class NetworksModel(object):
             raise MissingParameter("KCHNET0004E", {'name': params['name']})
 
         self._ensure_iface_up(iface)
-        if netinfo.is_bridge(iface):
+        if netinfo.is_bridge(iface) or netinfo.is_ovs_bridge(iface):
             if 'vlan_id' in params:
                 raise InvalidParameter('KCHNET0019E', {'name': iface})
             params['bridge'] = iface
diff --git a/src/wok/plugins/kimchi/netinfo.py b/src/wok/plugins/kimchi/netinfo.py
index c5746d7..f210da8 100644
--- a/src/wok/plugins/kimchi/netinfo.py
+++ b/src/wok/plugins/kimchi/netinfo.py
@@ -21,6 +21,8 @@ import ethtool
 import glob
 import os
 
+from distutils.spawn import find_executable
+from wok.utils import run_command
 
 NET_PATH = '/sys/class/net'
 NIC_PATH = '/sys/class/net/*/device'
@@ -79,6 +81,39 @@ def bridges():
 def is_bridge(iface):
     return iface in bridges()
 
+# OVS bridges need special handling because in some distributions, like Fedora,
+# the files bridge and brif are not created under /sys/class/net/<ovsbridge>.
+def ovs_bridges():
+    ovs_cmd = find_executable("ovs-vsctl")
+
+    # OVS not installed: there is no OVS bridge configured
+    if ovs_cmd is None:
+        return []
+
+    out, error, rc = run_command([ovs_cmd, '--oneline', 'list-br'])
+    if rc != 0 or len(out) == 0:
+        return []
+
+    return list(set(out.split('\n')) - set(['']))
+
+
+def is_ovs_bridge(iface):
+    return iface in ovs_bridges()
+
+
+def ovs_bridge_ports(ovsbr):
+    ovs_cmd = find_executable("ovs-vsctl")
+
+    # OVS not installed: there is no OVS bridge configured
+    if ovs_cmd is None:
+        return []
+
+    out, error, rc = run_command([ovs_cmd, '--oneline', 'list-ports', ovsbr])
+    if rc != 0 or len(out) == 0:
+        return []
+
+    return list(set(out.split('\n')) - set(['']))
+
 
 def all_interfaces():
     return [d.rsplit("/", 1)[-1] for d in glob.glob(NET_PATH + '/*')]
@@ -91,7 +126,12 @@ def slaves(bonding):
 
 
 def ports(bridge):
-    return os.listdir(BRIDGE_PORTS % bridge)
+    if bridge in bridges():
+        return os.listdir(BRIDGE_PORTS % bridge)
+    elif bridge in ovs_bridges():
+        return ovs_bridge_ports(bridge)
+
+    raise ValueError('unknown bridge %s' % bridge)
 
 
 def is_brport(nic):
@@ -136,9 +176,11 @@ def get_vlan_device(vlan):
 
 def get_bridge_port_device(bridge):
     """Return the nics list that belongs to bridge."""
-    #   br  --- v  --- bond --- nic1
-    if bridge not in bridges():
+
+    if bridge not in bridges() and bridge not in ovs_bridges():
         raise ValueError('unknown bridge %s' % bridge)
+
+    #   br  --- v  --- bond --- nic1
     nics = []
     for port in ports(bridge):
         if port in vlans():
@@ -155,9 +197,10 @@ def get_bridge_port_device(bridge):
 
 
 def aggregated_bridges():
-    return [bridge for bridge in bridges() if
-            (set(get_bridge_port_device(bridge)) & set(nics()))]
+    all_bridges = list(set(bridges() + ovs_bridges()))
 
+    return [bridge for bridge in all_bridges if
+            (set(get_bridge_port_device(bridge)) & set(nics()))]
 
 def bare_nics():
     "The nic is not a port of a bridge or a slave of bond."
@@ -184,7 +227,7 @@ def get_interface_type(iface):
             return "nic"
         if is_bonding(iface):
             return "bonding"
-        if is_bridge(iface):
+        if is_bridge(iface) or is_ovs_bridge(iface):
             return "bridge"
         if is_vlan(iface):
             return "vlan"
-- 
1.9.1