ch: pass TAP device name to CLH instead of fds

If TAP fds are passed, during reboot CLH closes all FDs and that
causes kernel to remove the tap device. This eventually causes guest
reboot failures.

Author: praveen-pk

src/ch/ch_domain.h

@@ -77,6 +77,7 @@ struct _virCHDomainObjPrivate {
 
     size_t tapfdSize;
     int *tapfd;
+    char *tapName;
 
     virThread vmThreadWatcher;
     int vmThreadWatcherStop;

src/ch/ch_monitor.c

@@ -315,8 +315,6 @@ virCHMonitorBuildNetJson(virDomainObjPtr vm, virJSONValuePtr nets, virDomainNetD
     char macaddr[VIR_MAC_STRING_BUFLEN];
     virCHDomainObjPrivatePtr priv = vm->privateData;
     virJSONValuePtr net;
-    virJSONValuePtr clh_tapfds = NULL;
-    int i = 0;
     net = virJSONValueNewObject();
 
     switch (netType) {
@@ -387,18 +385,12 @@ virCHMonitorBuildNetJson(virDomainObjPtr vm, virJSONValuePtr nets, virDomainNetD
         goto cleanup;
     }
 
-    clh_tapfds = virJSONValueNewArray();
-    for (i=0; i< priv->tapfdSize; i++) {
-        virJSONValueArrayAppend(clh_tapfds, virJSONValueNewNumberUint(priv->tapfd[i]));
-    }
-
-    if (virJSONValueObjectAppend(net, "fds", clh_tapfds) < 0)
+    if (virJSONValueObjectAppendString(net, "tap", priv->tapName) < 0)
         goto cleanup;
 
     if (virJSONValueObjectAppendString(net, "mac", virMacAddrFormat(&netdef->mac, macaddr)) < 0)
         goto cleanup;
 
-
     if (netdef->virtio != NULL) {
         if (netdef->virtio->iommu == VIR_TRISTATE_SWITCH_ON) {
             if (virJSONValueObjectAppendBoolean(net, "iommu", true) < 0)
@@ -616,7 +608,6 @@ chMonitorBuildSocketCmd(virDomainObjPtr vm, const char *socket_path)
         cmd = virCommandNew(CH_CMD);
 
     virCommandAddArgList(cmd, "--api-socket", socket_path, NULL);
-
     return cmd;
 }
 

src/ch/ch_process.c

@@ -38,6 +38,7 @@
 #include "virjson.h"
 #include "virlog.h"
 #include "virpidfile.h"
+#include "virstring.h"
 
 #define VIR_FROM_THIS VIR_FROM_CH
 
@@ -608,14 +609,20 @@ chProcessNetworkPrepareDevices(virCHDriverPtr driver, virDomainObjPtr vm)
             // This info will be used while generating Network Json
             priv->tapfd = g_steal_pointer(&tapfd);
             priv->tapfdSize = tapfdSize;
+            priv->tapName = g_new(char, IFNAMSIZ);
+            if (virStrcpy(priv->tapName, net->ifname, IFNAMSIZ) < 0) {
+                virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("net->ifname %s too big for destination"), net->ifname);
+                goto cleanup;
+            }
          }
     }
 
     return 0;
 
     cleanup:
         g_free(tapfd);
-    return 0;
+    return -1;
 }