[libvirt] [PATCH v4 06/29] network: move re-attach of bridge device out of network driver

[Daniel P. Berrangé]

During initial NIC setup the hypervisor drivers are responsible for
attaching the TAP device to the bridge device. Any fixup after libvirtd
restarts should thus also be their responsibility.

Reviewed-by: Laine Stump <laine at laine.org>
Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
---
 src/conf/domain_conf.c      | 20 +++++++++++++++++++-
 src/conf/domain_conf.h      |  2 +-
 src/network/bridge_driver.c | 27 ++++++---------------------
 3 files changed, 26 insertions(+), 23 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 1dde45a6fd..b94b70aabc 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -54,6 +54,7 @@
 #include "virsecret.h"
 #include "virstring.h"
 #include "virnetdev.h"
+#include "virnetdevtap.h"
 #include "virnetdevmacvlan.h"
 #include "virhostdev.h"
 #include "virmdev.h"
@@ -30444,8 +30445,25 @@ virDomainNetNotifyActualDevice(virConnectPtr conn,
     if (!(net = virNetworkLookupByName(conn, iface->data.network.name)))
         return;
 
-    netNotify(net, dom, iface);
+    if (netNotify(net, dom, iface) < 0)
+        goto cleanup;
+
+    if (virDomainNetGetActualType(iface) == VIR_DOMAIN_NET_TYPE_BRIDGE) {
+        /*
+         * NB: we can't notify the guest of any MTU change anyway,
+         * so there is no point in trying to learn the actualMTU
+         * (final arg to virNetDevTapReattachBridge())
+         */
+        if (virNetDevTapReattachBridge(iface->ifname,
+                                       iface->data.network.actual->data.bridge.brname,
+                                       &iface->mac, dom->uuid,
+                                       virDomainNetGetActualVirtPortProfile(iface),
+                                       virDomainNetGetActualVlan(iface),
+                                       iface->mtu, NULL) < 0)
+            goto cleanup;
+    }
 
+ cleanup:
     virObjectUnref(net);
 }
 
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 5910ed0beb..fb053a7ca3 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -3552,7 +3552,7 @@ typedef int
                                         virDomainDefPtr dom,
                                         virDomainNetDefPtr iface);
 
-typedef void
+typedef int
 (*virDomainNetNotifyActualDeviceImpl)(virNetworkPtr net,
                                       virDomainDefPtr dom,
                                       virDomainNetDefPtr iface);
diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index 4055939ade..8b36376761 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -4793,12 +4793,11 @@ networkAllocateActualDevice(virNetworkPtr net,
  * Called to notify the network driver when libvirtd is restarted and
  * finds an already running domain. If appropriate it will force an
  * allocation of the actual->direct.linkdev to get everything back in
- * order, or re-attach the interface's tap device to the network's
- * bridge.
+ * order.
  *
- * No return value (but does log any failures)
+ * Returns 0 on success, -1 on failure.
  */
-static void
+static int
 networkNotifyActualDevice(virNetworkPtr net,
                           virDomainDefPtr dom,
                           virDomainNetDefPtr iface)
@@ -4809,6 +4808,7 @@ networkNotifyActualDevice(virNetworkPtr net,
     virNetworkDefPtr netdef;
     virNetworkForwardIfDefPtr dev = NULL;
     size_t i;
+    int ret = -1;
 
     obj = virNetworkObjFindByName(driver->networks, net->name);
     if (!obj) {
@@ -4833,22 +4833,6 @@ networkNotifyActualDevice(virNetworkPtr net,
         goto error;
     }
 
-    /* see if we're connected to the correct bridge */
-    if (netdef->bridge) {
-        /*
-         * NB: we can't notify the guest of any MTU change anyway,
-         * so there is no point in trying to learn the actualMTU
-         * (final arg to virNetDevTapReattachBridge())
-         */
-        if (virNetDevTapReattachBridge(iface->ifname, netdef->bridge,
-                                       &iface->mac, dom->uuid,
-                                       virDomainNetGetActualVirtPortProfile(iface),
-                                       virDomainNetGetActualVlan(iface),
-                                       iface->mtu, NULL) < 0) {
-            goto error;
-        }
-    }
-
     if (!iface->data.network.actual ||
         (actualType != VIR_DOMAIN_NET_TYPE_DIRECT &&
          actualType != VIR_DOMAIN_NET_TYPE_HOSTDEV)) {
@@ -4977,10 +4961,11 @@ networkNotifyActualDevice(virNetworkPtr net,
         goto error;
     }
     networkLogAllocation(netdef, actualType, dev, iface, true);
+    ret = 0;
 
  cleanup:
     virNetworkObjEndAPI(&obj);
-    return;
+    return ret;
 
  error:
     goto cleanup;
-- 
2.20.1