[Qemu-devel] [PATCH] qmp: implement a qmp command get_link_status

[Wolfgang Link]

this qmp command returns the current link state from the given nic
this is impotent if the set_link failed or get an timeout.

Signed-off-by: Wolfgang Link <address@hidden>
---
 net/net.c        |   26 ++++++++++++++++++++++++++
 qapi-schema.json |   15 +++++++++++++++
 qmp-commands.hx  |   22 ++++++++++++++++++++++
 3 files changed, 63 insertions(+)

diff --git a/net/net.c b/net/net.c
index 7acc162..57c6f1e 100644
--- a/net/net.c
+++ b/net/net.c
@@ -1141,6 +1141,32 @@ void do_info_network(Monitor *mon, const QDict *qdict)
     }
 }
 
+int64_t qmp_get_link_status(const char *name, Error **errp)
+{
+    NetClientState *ncs[MAX_QUEUE_NUM];
+    NetClientState *nc;
+    int queues;
+    bool ret;
+
+    queues = qemu_find_net_clients_except(name, ncs,
+                                          NET_CLIENT_OPTIONS_KIND_MAX,
+                                          MAX_QUEUE_NUM);
+
+    if (queues == 0) {
+        error_set(errp, QERR_DEVICE_NOT_FOUND, name);
+        return (int64_t) -1;
+    }
+
+    nc = ncs[0];
+    ret = ncs[0]->link_down;
+
+    if (nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        ret = ncs[0]->peer->link_down;
+    }
+
+    return (int64_t) ret ? 0 : 1;
+}
+
 void qmp_set_link(const char *name, bool up, Error **errp)
 {
     NetClientState *ncs[MAX_QUEUE_NUM];
diff --git a/qapi-schema.json b/qapi-schema.json
index 9ffdcf8..c5321e6 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1200,6 +1200,21 @@
 { 'command': 'inject-nmi' }
 
 ##
+# @get_link_status
+#
+# Get the current link state of the nics or nic.
+#
+# @name: name of the nic you get the state of
+#
+# Return: If link is up 1
+#         If link is down 0
+#         If an error occure an empty string.
+#
+# Notes: this is an Proxmox VE extension and not offical part of Qemu.
+##
+{ 'command': 'get_link_status', 'data': {'name': 'str'}, 'returns': 'int'}
+
+##
 # @set_link:
 #
 # Sets the link status of a virtual network adapter.
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 718dd92..ecc501a 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1431,6 +1431,28 @@ Example:
 EQMP
 
     {
+       .name       = "get_link_status",
+       .args_type  = "name:s",
+       .mhandler.cmd_new = qmp_marshal_input_get_link_status,
+    },
+
+SQMP
+get_link_status
+--------
+
+Get the link status of a network adapter.
+
+Arguments:
+
+- "name": network device name (json-string)
+
+Example:
+
+-> { "execute": "set_link", "arguments": { "name": "e1000.0" } }
+<- { "return": {1} }
+EQMP
+
+    {
         .name       = "set_link",
         .args_type  = "name:s,up:b",
         .mhandler.cmd_new = qmp_marshal_input_set_link,
-- 
1.7.10.4