qapi: net: Add query-netdev command

The query-netdev command is used to get the configuration of the current
network device backends (netdevs).
This is the QMP analog of the HMP command "info network" but only for
netdevs (i.e. excluding NIC and hubports).

The query-netdev command returns an array of objects of the NetdevInfo
type, which are an extension of Netdev type. It means that response can
be used for netdev-add after small modification. This can be useful for
recreate the same netdev configuration.

Information about the network device is filled in when it is created or
modified and is available through the NetClientState->stored_config.

Signed-off-by: Alexey Kirillov <lekiravi@yandex-team.ru>
Acked-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

1 files changed, 29 insertions, 1 deletions

diff --git a/net/net.c b/net/net.c
index edf9b95418..9a2a6ab155 100644
--- a/net/net.c
+++ b/net/net.c
@@ -36,7 +36,6 @@
 #include "monitor/monitor.h"
 #include "qemu/help_option.h"
 #include "qapi/qapi-commands-net.h"
-#include "qapi/qapi-visit-net.h"
 #include "qapi/qmp/qdict.h"
 #include "qapi/qmp/qerror.h"
 #include "qemu/error-report.h"
@@ -353,6 +352,7 @@ static void qemu_free_net_client(NetClientState *nc)
     }
     g_free(nc->name);
     g_free(nc->model);
+    qapi_free_NetdevInfo(nc->stored_config);
     if (nc->destructor) {
         nc->destructor(nc);
     }
@@ -1289,6 +1289,34 @@ RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
     return filter_list;
 }
 
+NetdevInfoList *qmp_query_netdev(Error **errp)
+{
+    NetdevInfoList *list = NULL;
+    NetClientState *nc;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        /*
+         * Only look at netdevs (backend network devices), not for each queue
+         * or NIC / hubport
+         */
+        if (nc->stored_config) {
+            NetdevInfo *element = QAPI_CLONE(NetdevInfo, nc->stored_config);
+
+            g_free(element->id); /* Need to dealloc empty id after clone */
+            element->id = g_strdup(nc->name);
+
+            element->has_peer_id = nc->peer != NULL;
+            if (element->has_peer_id) {
+                element->peer_id = g_strdup(nc->peer->name);
+            }
+
+            QAPI_LIST_PREPEND(list, element);
+        }
+    }
+
+    return list;
+}
+
 void hmp_info_network(Monitor *mon, const QDict *qdict)
 {
     NetClientState *nc, *peer;