net: introduce qemu_find_net_clients_except()

In multiqueue, all NetClientState that belongs to the same netdev or nic has the
same id. So this patches introduces an helper qemu_find_net_clients_except()
which finds all NetClientState with the same id. This will be used by multiqueue
networking.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

include/net/net.h

@@ -68,6 +68,8 @@ typedef struct NICState {
 } NICState;
 
 NetClientState *qemu_find_netdev(const char *id);
+int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
+                                 NetClientOptionsKind type, int max);
 NetClientState *qemu_new_net_client(NetClientInfo *info,
                                     NetClientState *peer,
                                     const char *model,

net/net.c

@@ -508,6 +508,27 @@ NetClientState *qemu_find_netdev(const char *id)
     return NULL;
 }
 
+int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
+                                 NetClientOptionsKind type, int max)
+{
+    NetClientState *nc;
+    int ret = 0;
+
+    QTAILQ_FOREACH(nc, &net_clients, next) {
+        if (nc->info->type == type) {
+            continue;
+        }
+        if (!strcmp(nc->name, id)) {
+            if (ret < max) {
+                ncs[ret] = nc;
+            }
+            ret++;
+        }
+    }
+
+    return ret;
+}
+
 static int nic_get_free_idx(void)
 {
     int index;