network_driver: Use accessor for dnsmasqCaps

This is not an immutable pointer and can change during lifetime.
Therefore, in order to drop network driver lock, we must use an
internal accessor which does not lock the network driver yet, but
it will soon. Now it merely returns an referenced object.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

src/network/bridge_driver.c

@@ -106,6 +106,27 @@ static void networkDriverUnlock(virNetworkDriverStatePtr driver)
     virMutexUnlock(&driver->lock);
 }
 
+static dnsmasqCapsPtr
+networkGetDnsmasqCaps(virNetworkDriverStatePtr driver)
+{
+    dnsmasqCapsPtr ret;
+    ret = virObjectRef(driver->dnsmasqCaps);
+    return ret;
+}
+
+static int
+networkDnsmasqCapsRefresh(virNetworkDriverStatePtr driver)
+{
+    dnsmasqCapsPtr caps;
+
+    if (!(caps = dnsmasqCapsNewFromBinary(DNSMASQ)))
+        return -1;
+
+    virObjectUnref(driver->dnsmasqCaps);
+    driver->dnsmasqCaps = caps;
+    return 0;
+}
+
 static int networkStateCleanup(void);
 
 static int networkStartNetwork(virNetworkDriverStatePtr driver,
@@ -364,6 +385,7 @@ networkUpdateState(virNetworkObjPtr obj,
                    void *opaque)
 {
     virNetworkDriverStatePtr driver = opaque;
+    dnsmasqCapsPtr dnsmasq_caps = networkGetDnsmasqCaps(driver);
     int ret = -1;
 
     virObjectLock(obj);
@@ -408,7 +430,7 @@ networkUpdateState(virNetworkObjPtr obj,
         ignore_value(virPidFileReadIfAlive(driver->pidDir,
                                            obj->def->name,
                                            &obj->dnsmasqPid,
-                                           dnsmasqCapsGetBinaryPath(driver->dnsmasqCaps)));
+                                           dnsmasqCapsGetBinaryPath(dnsmasq_caps)));
         radvdpidbase = networkRadvdPidfileBasename(obj->def->name);
         if (!radvdpidbase)
             goto cleanup;
@@ -422,6 +444,7 @@ networkUpdateState(virNetworkObjPtr obj,
     ret = 0;
  cleanup:
     virObjectUnlock(obj);
+    virObjectUnref(dnsmasq_caps);
     return ret;
 }
 
@@ -1284,6 +1307,7 @@ networkBuildDhcpDaemonCommandLine(virNetworkDriverStatePtr driver,
                                   char *pidfile,
                                   dnsmasqContext *dctx)
 {
+    dnsmasqCapsPtr dnsmasq_caps = networkGetDnsmasqCaps(driver);
     virCommandPtr cmd = NULL;
     int ret = -1;
     char *configfile = NULL;
@@ -1293,7 +1317,7 @@ networkBuildDhcpDaemonCommandLine(virNetworkDriverStatePtr driver,
     network->dnsmasqPid = -1;
 
     if (networkDnsmasqConfContents(network, pidfile, &configstr,
-                                   dctx, driver->dnsmasqCaps) < 0)
+                                   dctx, dnsmasq_caps) < 0)
         goto cleanup;
     if (!configstr)
         goto cleanup;
@@ -1316,7 +1340,7 @@ networkBuildDhcpDaemonCommandLine(virNetworkDriverStatePtr driver,
                                                   LIBEXECDIR)))
         goto cleanup;
 
-    cmd = virCommandNew(dnsmasqCapsGetBinaryPath(driver->dnsmasqCaps));
+    cmd = virCommandNew(dnsmasqCapsGetBinaryPath(dnsmasq_caps));
     virCommandAddArgFormat(cmd, "--conf-file=%s", configfile);
     /* Libvirt gains full control of leases database */
     virCommandAddArgFormat(cmd, "--leasefile-ro");
@@ -1326,6 +1350,7 @@ networkBuildDhcpDaemonCommandLine(virNetworkDriverStatePtr driver,
     *cmdout = cmd;
     ret = 0;
  cleanup:
+    virObjectUnref(dnsmasq_caps);
     VIR_FREE(configfile);
     VIR_FREE(configstr);
     VIR_FREE(leaseshelper_path);
@@ -1369,7 +1394,7 @@ networkStartDhcpDaemon(virNetworkDriverStatePtr driver,
     if (dctx == NULL)
         goto cleanup;
 
-    if (dnsmasqCapsRefresh(&driver->dnsmasqCaps, NULL) < 0)
+    if (networkDnsmasqCapsRefresh(driver) < 0)
         goto cleanup;
 
     ret = networkBuildDhcpDaemonCommandLine(driver, network, &cmd, pidfile, dctx);
@@ -1623,6 +1648,7 @@ static int
 networkStartRadvd(virNetworkDriverStatePtr driver,
                   virNetworkObjPtr network)
 {
+    dnsmasqCapsPtr dnsmasq_caps = networkGetDnsmasqCaps(driver);
     char *pidfile = NULL;
     char *radvdpidbase = NULL;
     char *configfile = NULL;
@@ -1632,7 +1658,7 @@ networkStartRadvd(virNetworkDriverStatePtr driver,
     network->radvdPid = -1;
 
     /* Is dnsmasq handling RA? */
-    if (DNSMASQ_RA_SUPPORT(driver->dnsmasqCaps)) {
+    if (DNSMASQ_RA_SUPPORT(dnsmasq_caps)) {
         ret = 0;
         goto cleanup;
     }
@@ -1698,6 +1724,7 @@ networkStartRadvd(virNetworkDriverStatePtr driver,
 
     ret = 0;
  cleanup:
+    virObjectUnref(dnsmasq_caps);
     virCommandFree(cmd);
     VIR_FREE(configfile);
     VIR_FREE(radvdpidbase);
@@ -1709,10 +1736,12 @@ static int
 networkRefreshRadvd(virNetworkDriverStatePtr driver,
                     virNetworkObjPtr network)
 {
+    dnsmasqCapsPtr dnsmasq_caps = networkGetDnsmasqCaps(driver);
     char *radvdpidbase;
 
     /* Is dnsmasq handling RA? */
-    if (DNSMASQ_RA_SUPPORT(driver->dnsmasqCaps)) {
+    if (DNSMASQ_RA_SUPPORT(dnsmasq_caps)) {
+        virObjectUnref(dnsmasq_caps);
         if (network->radvdPid <= 0)
             return 0;
         /* radvd should not be running but in case it is */
@@ -1726,6 +1755,7 @@ networkRefreshRadvd(virNetworkDriverStatePtr driver,
         network->radvdPid = -1;
         return 0;
     }
+    virObjectUnref(dnsmasq_caps);
 
     /* if there's no running radvd, just start it */
     if (network->radvdPid <= 0 || (kill(network->radvdPid, 0) < 0))