qemu: Report tunnelled post-copy migration as unsupported

Post-copy migration needs bi-directional communication between the
source and the destination QEMU processes, which is not supported by
tunnelled migration.

https://bugzilla.redhat.com/show_bug.cgi?id=1371358Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

src/qemu/qemu_migration.c

@@ -3167,6 +3167,12 @@ qemuMigrationBeginPhase(virQEMUDriverPtr driver,
         goto cleanup;
     }
 
+    if (flags & VIR_MIGRATE_POSTCOPY && flags & VIR_MIGRATE_TUNNELLED) {
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                       _("post-copy is not supported with tunnelled migration"));
+        goto cleanup;
+    }
+
     if (flags & (VIR_MIGRATE_NON_SHARED_DISK | VIR_MIGRATE_NON_SHARED_INC)) {
         bool has_drive_mirror =  virQEMUCapsGet(priv->qemuCaps,
                                                 QEMU_CAPS_DRIVE_MIRROR);
@@ -3645,6 +3651,12 @@ qemuMigrationPrepareAny(virQEMUDriverPtr driver,
         goto cleanup;
     }
 
+    if (flags & VIR_MIGRATE_POSTCOPY && flags & VIR_MIGRATE_TUNNELLED) {
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+                       _("post-copy is not supported with tunnelled migration"));
+        goto cleanup;
+    }
+
     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))
         goto cleanup;