qapi: Change Netdev into a flat union

This is a mostly-mechanical conversion that creates a new flat
union 'Netdev' QAPI type that covers all the branches of the
former 'NetClientOptions' simple union, where the branches are
now listed in a new 'NetClientDriver' enum rather than generated
from the simple union.  The existence of a flat union has no
change to the command line syntax accepted for new code, and
will make it possible for a future patch to switch the QMP
command to parse a boxed union for no change to valid QMP; but
it does have some ripple effect on the C code when dealing with
the new types.

While making the conversion, note that the 'NetLegacy' type
remains unchanged: it applies only to legacy command line options,
and will not be ported to QMP, so it should remain a wrapper
around a simple union; to avoid confusion, the type named
'NetClientOptions' is now gone, and we introduce 'NetLegacyOptions'
in its place.  Then, in the C code, we convert from NetLegacy to
Netdev as soon as possible, so that the bulk of the net stack
only has to deal with one QAPI type, not two.  Note that since
the old legacy code always rejected 'hubport', we can just omit
that branch from the new 'NetLegacyOptions' simple union.

Based on an idea originally by Zoltán Kővágó <DirtY.iCE.hu@gmail.com>:
Message-Id: <01a527fbf1a5de880091f98cf011616a78adeeee.1441627176.git.DirtY.iCE.hu@gmail.com>
although the sed script in that patch no longer applies due to
other changes in the tree since then, and I also did some manual
cleanups (such as fixing whitespace to keep checkpatch happy).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-13-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Fixup from Eric squashed in]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

12 files changed, 140 insertions, 103 deletions

diff --git a/net/dump.c b/net/dump.c
index f8a500f715..89a149b5dd 100644
--- a/net/dump.c
+++ b/net/dump.c
@@ -172,7 +172,7 @@ static void dumpclient_cleanup(NetClientState *nc)
 }
 
 static NetClientInfo net_dump_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_DUMP,
+    .type = NET_CLIENT_DRIVER_DUMP,
     .size = sizeof(DumpNetClient),
     .receive = dumpclient_receive,
     .receive_iov = dumpclient_receive_iov,
@@ -189,8 +189,8 @@ int net_init_dump(const Netdev *netdev, const char *name,
     NetClientState *nc;
     DumpNetClient *dnc;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_DUMP);
-    dump = netdev->opts->u.dump.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_DUMP);
+    dump = &netdev->u.dump;
 
     assert(peer);
 
diff --git a/net/filter.c b/net/filter.c
index 8ac79f3b7b..888fe6dd93 100644
--- a/net/filter.c
+++ b/net/filter.c
@@ -201,7 +201,7 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
     }
 
     queues = qemu_find_net_clients_except(nf->netdev_id, ncs,
-                                          NET_CLIENT_OPTIONS_KIND_NIC,
+                                          NET_CLIENT_DRIVER_NIC,
                                           MAX_QUEUE_NUM);
     if (queues < 1) {
         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "netdev",
diff --git a/net/hub.c b/net/hub.c
index ec4626f2c0..32d8cf5cd4 100644
--- a/net/hub.c
+++ b/net/hub.c
@@ -131,7 +131,7 @@ static void net_hub_port_cleanup(NetClientState *nc)
 }
 
 static NetClientInfo net_hub_port_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_HUBPORT,
+    .type = NET_CLIENT_DRIVER_HUBPORT,
     .size = sizeof(NetHubPort),
     .can_receive = net_hub_port_can_receive,
     .receive = net_hub_port_receive,
@@ -266,10 +266,10 @@ int net_hub_id_for_client(NetClientState *nc, int *id)
 {
     NetHubPort *port;
 
-    if (nc->info->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) {
+    if (nc->info->type == NET_CLIENT_DRIVER_HUBPORT) {
         port = DO_UPCAST(NetHubPort, nc, nc);
     } else if (nc->peer != NULL && nc->peer->info->type ==
-            NET_CLIENT_OPTIONS_KIND_HUBPORT) {
+            NET_CLIENT_DRIVER_HUBPORT) {
         port = DO_UPCAST(NetHubPort, nc, nc->peer);
     } else {
         return -ENOENT;
@@ -286,9 +286,9 @@ int net_init_hubport(const Netdev *netdev, const char *name,
 {
     const NetdevHubPortOptions *hubport;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_HUBPORT);
+    assert(netdev->type == NET_CLIENT_DRIVER_HUBPORT);
     assert(!peer);
-    hubport = netdev->opts->u.hubport.data;
+    hubport = &netdev->u.hubport;
 
     net_hub_add_port(hubport->hubid, name);
     return 0;
@@ -315,14 +315,14 @@ void net_hub_check_clients(void)
             }
 
             switch (peer->info->type) {
-            case NET_CLIENT_OPTIONS_KIND_NIC:
+            case NET_CLIENT_DRIVER_NIC:
                 has_nic = 1;
                 break;
-            case NET_CLIENT_OPTIONS_KIND_USER:
-            case NET_CLIENT_OPTIONS_KIND_TAP:
-            case NET_CLIENT_OPTIONS_KIND_SOCKET:
-            case NET_CLIENT_OPTIONS_KIND_VDE:
-            case NET_CLIENT_OPTIONS_KIND_VHOST_USER:
+            case NET_CLIENT_DRIVER_USER:
+            case NET_CLIENT_DRIVER_TAP:
+            case NET_CLIENT_DRIVER_SOCKET:
+            case NET_CLIENT_DRIVER_VDE:
+            case NET_CLIENT_DRIVER_VHOST_USER:
                 has_host_dev = 1;
                 break;
             default:
diff --git a/net/l2tpv3.c b/net/l2tpv3.c
index df02f5bdcc..6745b78990 100644
--- a/net/l2tpv3.c
+++ b/net/l2tpv3.c
@@ -516,7 +516,7 @@ static void net_l2tpv3_cleanup(NetClientState *nc)
 }
 
 static NetClientInfo net_l2tpv3_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_L2TPV3,
+    .type = NET_CLIENT_DRIVER_L2TPV3,
     .size = sizeof(NetL2TPV3State),
     .receive = net_l2tpv3_receive_dgram,
     .receive_iov = net_l2tpv3_receive_dgram_iov,
@@ -545,8 +545,8 @@ int net_init_l2tpv3(const Netdev *netdev,
     s->queue_tail = 0;
     s->header_mismatch = false;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_L2TPV3);
-    l2tpv3 = netdev->opts->u.l2tpv3.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_L2TPV3);
+    l2tpv3 = &netdev->u.l2tpv3;
 
     if (l2tpv3->has_ipv6 && l2tpv3->ipv6) {
         s->ipv6 = l2tpv3->ipv6;
diff --git a/net/net.c b/net/net.c
index d80fd82210..4a7f392baf 100644
--- a/net/net.c
+++ b/net/net.c
@@ -289,7 +289,7 @@ NICState *qemu_new_nic(NetClientInfo *info,
     NICState *nic;
     int i, queues = MAX(1, conf->peers.queues);
 
-    assert(info->type == NET_CLIENT_OPTIONS_KIND_NIC);
+    assert(info->type == NET_CLIENT_DRIVER_NIC);
     assert(info->size >= sizeof(NICState));
 
     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
@@ -360,13 +360,13 @@ void qemu_del_net_client(NetClientState *nc)
     int queues, i;
     NetFilterState *nf, *next;
 
-    assert(nc->info->type != NET_CLIENT_OPTIONS_KIND_NIC);
+    assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
 
     /* If the NetClientState belongs to a multiqueue backend, we will change all
      * other NetClientStates also.
      */
     queues = qemu_find_net_clients_except(nc->name, ncs,
-                                          NET_CLIENT_OPTIONS_KIND_NIC,
+                                          NET_CLIENT_DRIVER_NIC,
                                           MAX_QUEUE_NUM);
     assert(queues != 0);
 
@@ -375,7 +375,7 @@ void qemu_del_net_client(NetClientState *nc)
     }
 
     /* If there is a peer NIC, delete and cleanup client, but do not free. */
-    if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+    if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
         NICState *nic = qemu_get_nic(nc->peer);
         if (nic->peer_deleted) {
             return;
@@ -431,7 +431,7 @@ void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
     NetClientState *nc;
 
     QTAILQ_FOREACH(nc, &net_clients, next) {
-        if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
             if (nc->queue_index == 0) {
                 func(qemu_get_nic(nc), opaque);
             }
@@ -603,7 +603,7 @@ void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
 {
     nc->receive_disabled = 0;
 
-    if (nc->peer && nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) {
+    if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
         if (net_hub_flush(nc->peer)) {
             qemu_notify_event();
         }
@@ -777,7 +777,7 @@ NetClientState *qemu_find_netdev(const char *id)
     NetClientState *nc;
 
     QTAILQ_FOREACH(nc, &net_clients, next) {
-        if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC)
+        if (nc->info->type == NET_CLIENT_DRIVER_NIC)
             continue;
         if (!strcmp(nc->name, id)) {
             return nc;
@@ -788,7 +788,7 @@ NetClientState *qemu_find_netdev(const char *id)
 }
 
 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
-                                 NetClientOptionsKind type, int max)
+                                 NetClientDriver type, int max)
 {
     NetClientState *nc;
     int ret = 0;
@@ -869,8 +869,8 @@ static int net_init_nic(const Netdev *netdev, const char *name,
     NICInfo *nd;
     const NetLegacyNicOptions *nic;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_NIC);
-    nic = netdev->opts->u.nic.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_NIC);
+    nic = &netdev->u.nic;
 
     idx = nic_get_free_idx();
     if (idx == -1 || nb_nics >= MAX_NICS) {
@@ -930,39 +930,38 @@ static int net_init_nic(const Netdev *netdev, const char *name,
 }
 
 
-static int (* const net_client_init_fun[NET_CLIENT_OPTIONS_KIND__MAX])(
+static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
     const Netdev *netdev,
     const char *name,
     NetClientState *peer, Error **errp) = {
-        [NET_CLIENT_OPTIONS_KIND_NIC]       = net_init_nic,
+        [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
 #ifdef CONFIG_SLIRP
-        [NET_CLIENT_OPTIONS_KIND_USER]      = net_init_slirp,
+        [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
 #endif
-        [NET_CLIENT_OPTIONS_KIND_TAP]       = net_init_tap,
-        [NET_CLIENT_OPTIONS_KIND_SOCKET]    = net_init_socket,
+        [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
+        [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
 #ifdef CONFIG_VDE
-        [NET_CLIENT_OPTIONS_KIND_VDE]       = net_init_vde,
+        [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
 #endif
 #ifdef CONFIG_NETMAP
-        [NET_CLIENT_OPTIONS_KIND_NETMAP]    = net_init_netmap,
+        [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
 #endif
-        [NET_CLIENT_OPTIONS_KIND_DUMP]      = net_init_dump,
+        [NET_CLIENT_DRIVER_DUMP]      = net_init_dump,
 #ifdef CONFIG_NET_BRIDGE
-        [NET_CLIENT_OPTIONS_KIND_BRIDGE]    = net_init_bridge,
+        [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
 #endif
-        [NET_CLIENT_OPTIONS_KIND_HUBPORT]   = net_init_hubport,
+        [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
 #ifdef CONFIG_VHOST_NET_USED
-        [NET_CLIENT_OPTIONS_KIND_VHOST_USER] = net_init_vhost_user,
+        [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
 #endif
 #ifdef CONFIG_L2TPV3
-        [NET_CLIENT_OPTIONS_KIND_L2TPV3]    = net_init_l2tpv3,
+        [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
 #endif
 };
 
 
 static int net_client_init1(const void *object, int is_netdev, Error **errp)
 {
-    const NetClientOptions *opts;
     Netdev legacy = {0};
     const Netdev *netdev;
     const char *name;
@@ -970,34 +969,72 @@ static int net_client_init1(const void *object, int is_netdev, Error **errp)
 
     if (is_netdev) {
         netdev = object;
-        opts = netdev->opts;
         name = netdev->id;
 
-        if (opts->type == NET_CLIENT_OPTIONS_KIND_DUMP ||
-            opts->type == NET_CLIENT_OPTIONS_KIND_NIC ||
-            !net_client_init_fun[opts->type]) {
+        if (netdev->type == NET_CLIENT_DRIVER_DUMP ||
+            netdev->type == NET_CLIENT_DRIVER_NIC ||
+            !net_client_init_fun[netdev->type]) {
             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
                        "a netdev backend type");
             return -1;
         }
     } else {
         const NetLegacy *net = object;
+        const NetLegacyOptions *opts = net->opts;
         legacy.id = net->id;
-        opts = legacy.opts = net->opts;
         netdev = &legacy;
         /* missing optional values have been initialized to "all bits zero" */
         name = net->has_id ? net->id : net->name;
 
-        if (opts->type == NET_CLIENT_OPTIONS_KIND_NONE) {
+        /* Map the old options to the new flat type */
+        switch (opts->type) {
+        case NET_LEGACY_OPTIONS_KIND_NONE:
             return 0; /* nothing to do */
-        }
-        if (opts->type == NET_CLIENT_OPTIONS_KIND_HUBPORT) {
-            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
-                       "a net type");
-            return -1;
+        case NET_LEGACY_OPTIONS_KIND_NIC:
+            legacy.type = NET_CLIENT_DRIVER_NIC;
+            legacy.u.nic = *opts->u.nic.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_USER:
+            legacy.type = NET_CLIENT_DRIVER_USER;
+            legacy.u.user = *opts->u.user.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_TAP:
+            legacy.type = NET_CLIENT_DRIVER_TAP;
+            legacy.u.tap = *opts->u.tap.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_L2TPV3:
+            legacy.type = NET_CLIENT_DRIVER_L2TPV3;
+            legacy.u.l2tpv3 = *opts->u.l2tpv3.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_SOCKET:
+            legacy.type = NET_CLIENT_DRIVER_SOCKET;
+            legacy.u.socket = *opts->u.socket.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_VDE:
+            legacy.type = NET_CLIENT_DRIVER_VDE;
+            legacy.u.vde = *opts->u.vde.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_DUMP:
+            legacy.type = NET_CLIENT_DRIVER_DUMP;
+            legacy.u.dump = *opts->u.dump.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_BRIDGE:
+            legacy.type = NET_CLIENT_DRIVER_BRIDGE;
+            legacy.u.bridge = *opts->u.bridge.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_NETMAP:
+            legacy.type = NET_CLIENT_DRIVER_NETMAP;
+            legacy.u.netmap = *opts->u.netmap.data;
+            break;
+        case NET_LEGACY_OPTIONS_KIND_VHOST_USER:
+            legacy.type = NET_CLIENT_DRIVER_VHOST_USER;
+            legacy.u.vhost_user = *opts->u.vhost_user.data;
+            break;
+        default:
+            abort();
         }
 
-        if (!net_client_init_fun[opts->type]) {
+        if (!net_client_init_fun[netdev->type]) {
             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
                        "a net backend type (maybe it is not compiled "
                        "into this binary)");
@@ -1005,17 +1042,17 @@ static int net_client_init1(const void *object, int is_netdev, Error **errp)
         }
 
         /* Do not add to a vlan if it's a nic with a netdev= parameter. */
-        if (opts->type != NET_CLIENT_OPTIONS_KIND_NIC ||
+        if (netdev->type != NET_CLIENT_DRIVER_NIC ||
             !opts->u.nic.data->has_netdev) {
             peer = net_hub_add_port(net->has_vlan ? net->vlan : 0, NULL);
         }
     }
 
-    if (net_client_init_fun[opts->type](netdev, name, peer, errp) < 0) {
+    if (net_client_init_fun[netdev->type](netdev, name, peer, errp) < 0) {
         /* FIXME drop when all init functions store an Error */
         if (errp && !*errp) {
             error_setg(errp, QERR_DEVICE_INIT_FAILED,
-                       NetClientOptionsKind_lookup[opts->type]);
+                       NetClientDriver_lookup[netdev->type]);
         }
         return -1;
     }
@@ -1135,7 +1172,7 @@ void hmp_host_net_remove(Monitor *mon, const QDict *qdict)
                      device, vlan_id);
         return;
     }
-    if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+    if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
         error_report("invalid host network device '%s'", device);
         return;
     }
@@ -1226,7 +1263,7 @@ void print_net_client(Monitor *mon, NetClientState *nc)
 
     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
                    nc->queue_index,
-                   NetClientOptionsKind_lookup[nc->info->type],
+                   NetClientDriver_lookup[nc->info->type],
                    nc->info_str);
     if (!QTAILQ_EMPTY(&nc->filters)) {
         monitor_printf(mon, "filters:\n");
@@ -1256,7 +1293,7 @@ RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
         }
 
         /* only query rx-filter information of NIC */
-        if (nc->info->type != NET_CLIENT_OPTIONS_KIND_NIC) {
+        if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
             if (has_name) {
                 error_setg(errp, "net client(%s) isn't a NIC", name);
                 return NULL;
@@ -1302,7 +1339,7 @@ RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
 void hmp_info_network(Monitor *mon, const QDict *qdict)
 {
     NetClientState *nc, *peer;
-    NetClientOptionsKind type;
+    NetClientDriver type;
 
     net_hub_info(mon);
 
@@ -1315,10 +1352,10 @@ void hmp_info_network(Monitor *mon, const QDict *qdict)
             continue;
         }
 
-        if (!peer || type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        if (!peer || type == NET_CLIENT_DRIVER_NIC) {
             print_net_client(mon, nc);
         } /* else it's a netdev connected to a NIC, printed with the NIC */
-        if (peer && type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        if (peer && type == NET_CLIENT_DRIVER_NIC) {
             monitor_printf(mon, " \\ ");
             print_net_client(mon, peer);
         }
@@ -1332,7 +1369,7 @@ void qmp_set_link(const char *name, bool up, Error **errp)
     int queues, i;
 
     queues = qemu_find_net_clients_except(name, ncs,
-                                          NET_CLIENT_OPTIONS_KIND__MAX,
+                                          NET_CLIENT_DRIVER__MAX,
                                           MAX_QUEUE_NUM);
 
     if (queues == 0) {
@@ -1359,7 +1396,7 @@ void qmp_set_link(const char *name, bool up, Error **errp)
          * multiple clients that can still communicate with each other in
          * disconnected mode. For now maintain this compatibility.
          */
-        if (nc->peer->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
             for (i = 0; i < queues; i++) {
                 ncs[i]->peer->link_down = !up;
             }
@@ -1400,7 +1437,7 @@ void net_cleanup(void)
      */
     while (!QTAILQ_EMPTY(&net_clients)) {
         nc = QTAILQ_FIRST(&net_clients);
-        if (nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC) {
+        if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
             qemu_del_nic(qemu_get_nic(nc));
         } else {
             qemu_del_net_client(nc);
@@ -1420,7 +1457,7 @@ void net_check_clients(void)
     QTAILQ_FOREACH(nc, &net_clients, next) {
         if (!nc->peer) {
             fprintf(stderr, "Warning: %s %s has no peer\n",
-                    nc->info->type == NET_CLIENT_OPTIONS_KIND_NIC ?
+                    nc->info->type == NET_CLIENT_DRIVER_NIC ?
                     "nic" : "netdev", nc->name);
         }
     }
diff --git a/net/netmap.c b/net/netmap.c
index beb8d2841c..2d11a8f4be 100644
--- a/net/netmap.c
+++ b/net/netmap.c
@@ -400,7 +400,7 @@ static void netmap_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
 
 /* NetClientInfo methods */
 static NetClientInfo net_netmap_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_NETMAP,
+    .type = NET_CLIENT_DRIVER_NETMAP,
     .size = sizeof(NetmapState),
     .receive = netmap_receive,
     .receive_iov = netmap_receive_iov,
@@ -421,7 +421,7 @@ static NetClientInfo net_netmap_info = {
 int net_init_netmap(const Netdev *netdev,
                     const char *name, NetClientState *peer, Error **errp)
 {
-    const NetdevNetmapOptions *netmap_opts = netdev->opts->u.netmap.data;
+    const NetdevNetmapOptions *netmap_opts = &netdev->u.netmap;
     struct nm_desc *nmd;
     NetClientState *nc;
     Error *err = NULL;
diff --git a/net/slirp.c b/net/slirp.c
index ca34badb76..facc30ed18 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -137,7 +137,7 @@ static void net_slirp_cleanup(NetClientState *nc)
 }
 
 static NetClientInfo net_slirp_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_USER,
+    .type = NET_CLIENT_DRIVER_USER,
     .size = sizeof(SlirpState),
     .receive = net_slirp_receive,
     .cleanup = net_slirp_cleanup,
@@ -839,8 +839,8 @@ int net_init_slirp(const Netdev *netdev, const char *name,
     const char **dnssearch;
     bool ipv4 = true, ipv6 = true;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_USER);
-    user = netdev->opts->u.user.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_USER);
+    user = &netdev->u.user;
 
     if ((user->has_ipv6 && user->ipv6 && !user->has_ipv4) ||
         (user->has_ipv4 && !user->ipv4)) {
diff --git a/net/socket.c b/net/socket.c
index 6e5c902ea9..17e635de20 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -311,7 +311,7 @@ static void net_socket_cleanup(NetClientState *nc)
 }
 
 static NetClientInfo net_dgram_socket_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_SOCKET,
+    .type = NET_CLIENT_DRIVER_SOCKET,
     .size = sizeof(NetSocketState),
     .receive = net_socket_receive_dgram,
     .cleanup = net_socket_cleanup,
@@ -395,7 +395,7 @@ static void net_socket_connect(void *opaque)
 }
 
 static NetClientInfo net_socket_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_SOCKET,
+    .type = NET_CLIENT_DRIVER_SOCKET,
     .size = sizeof(NetSocketState),
     .receive = net_socket_receive,
     .cleanup = net_socket_cleanup,
@@ -670,8 +670,8 @@ int net_init_socket(const Netdev *netdev, const char *name,
     Error *err = NULL;
     const NetdevSocketOptions *sock;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_SOCKET);
-    sock = netdev->opts->u.socket.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_SOCKET);
+    sock = &netdev->u.socket;
 
     if (sock->has_fd + sock->has_listen + sock->has_connect + sock->has_mcast +
         sock->has_udp != 1) {
diff --git a/net/tap-win32.c b/net/tap-win32.c
index 0f23b19c96..662f9b63e1 100644
--- a/net/tap-win32.c
+++ b/net/tap-win32.c
@@ -750,7 +750,7 @@ static void tap_set_vnet_hdr_len(NetClientState *nc, int len)
 }
 
 static NetClientInfo net_tap_win32_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_TAP,
+    .type = NET_CLIENT_DRIVER_TAP,
     .size = sizeof(TAPState),
     .receive = tap_receive,
     .cleanup = tap_cleanup,
@@ -794,8 +794,8 @@ int net_init_tap(const Netdev *netdev, const char *name,
     /* FIXME error_setg(errp, ...) on failure */
     const NetdevTapOptions *tap;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_TAP);
-    tap = netdev->opts->u.tap.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_TAP);
+    tap = &netdev->u.tap;
 
     if (!tap->has_ifname) {
         error_report("tap: no interface name");
diff --git a/net/tap.c b/net/tap.c
index ceb8c43821..7928a09daa 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -223,7 +223,7 @@ static bool tap_has_ufo(NetClientState *nc)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
 
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
 
     return s->has_ufo;
 }
@@ -232,7 +232,7 @@ static bool tap_has_vnet_hdr(NetClientState *nc)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
 
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
 
     return !!s->host_vnet_hdr_len;
 }
@@ -241,7 +241,7 @@ static bool tap_has_vnet_hdr_len(NetClientState *nc, int len)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
 
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
 
     return !!tap_probe_vnet_hdr_len(s->fd, len);
 }
@@ -250,7 +250,7 @@ static void tap_set_vnet_hdr_len(NetClientState *nc, int len)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
 
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
     assert(len == sizeof(struct virtio_net_hdr_mrg_rxbuf) ||
            len == sizeof(struct virtio_net_hdr));
 
@@ -262,7 +262,7 @@ static void tap_using_vnet_hdr(NetClientState *nc, bool using_vnet_hdr)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
 
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
     assert(!!s->host_vnet_hdr_len == using_vnet_hdr);
 
     s->using_vnet_hdr = using_vnet_hdr;
@@ -336,14 +336,14 @@ static void tap_poll(NetClientState *nc, bool enable)
 int tap_get_fd(NetClientState *nc)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
     return s->fd;
 }
 
 /* fd support */
 
 static NetClientInfo net_tap_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_TAP,
+    .type = NET_CLIENT_DRIVER_TAP,
     .size = sizeof(TAPState),
     .receive = tap_receive,
     .receive_raw = tap_receive_raw,
@@ -579,8 +579,8 @@ int net_init_bridge(const Netdev *netdev, const char *name,
     TAPState *s;
     int fd, vnet_hdr;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_BRIDGE);
-    bridge = netdev->opts->u.bridge.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_BRIDGE);
+    bridge = &netdev->u.bridge;
 
     helper = bridge->has_helper ? bridge->helper : DEFAULT_BRIDGE_HELPER;
     br     = bridge->has_br     ? bridge->br     : DEFAULT_BRIDGE_INTERFACE;
@@ -747,8 +747,8 @@ int net_init_tap(const Netdev *netdev, const char *name,
     const char *vhostfdname;
     char ifname[128];
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_TAP);
-    tap = netdev->opts->u.tap.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_TAP);
+    tap = &netdev->u.tap;
     queues = tap->has_queues ? tap->queues : 1;
     vhostfdname = tap->has_vhostfd ? tap->vhostfd : NULL;
 
@@ -911,7 +911,7 @@ int net_init_tap(const Netdev *netdev, const char *name,
 VHostNetState *tap_get_vhost_net(NetClientState *nc)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_TAP);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
     return s->vhost_net;
 }
 
diff --git a/net/vde.c b/net/vde.c
index 53cdbbf0ea..e50e5d6394 100644
--- a/net/vde.c
+++ b/net/vde.c
@@ -68,7 +68,7 @@ static void vde_cleanup(NetClientState *nc)
 }
 
 static NetClientInfo net_vde_info = {
-    .type = NET_CLIENT_OPTIONS_KIND_VDE,
+    .type = NET_CLIENT_DRIVER_VDE,
     .size = sizeof(VDEState),
     .receive = vde_receive,
     .cleanup = vde_cleanup,
@@ -115,8 +115,8 @@ int net_init_vde(const Netdev *netdev, const char *name,
     /* FIXME error_setg(errp, ...) on failure */
     const NetdevVdeOptions *vde;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_VDE);
-    vde = netdev->opts->u.vde.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_VDE);
+    vde = &netdev->u.vde;
 
     /* missing optional values have been initialized to "all bits zero" */
     if (net_vde_init(peer, "vde", name, vde->sock, vde->port, vde->group,
diff --git a/net/vhost-user.c b/net/vhost-user.c
index dfdcca221c..c4d63e05eb 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -34,14 +34,14 @@ typedef struct VhostUserChardevProps {
 VHostNetState *vhost_user_get_vhost_net(NetClientState *nc)
 {
     VhostUserState *s = DO_UPCAST(VhostUserState, nc, nc);
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER);
+    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
     return s->vhost_net;
 }
 
 uint64_t vhost_user_get_acked_features(NetClientState *nc)
 {
     VhostUserState *s = DO_UPCAST(VhostUserState, nc, nc);
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER);
+    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
     return s->acked_features;
 }
 
@@ -56,7 +56,7 @@ static void vhost_user_stop(int queues, NetClientState *ncs[])
     int i;
 
     for (i = 0; i < queues; i++) {
-        assert (ncs[i]->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER);
+        assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER);
 
         s = DO_UPCAST(VhostUserState, nc, ncs[i]);
         if (!vhost_user_running(s)) {
@@ -82,7 +82,7 @@ static int vhost_user_start(int queues, NetClientState *ncs[])
     options.backend_type = VHOST_BACKEND_TYPE_USER;
 
     for (i = 0; i < queues; i++) {
-        assert (ncs[i]->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER);
+        assert(ncs[i]->info->type == NET_CLIENT_DRIVER_VHOST_USER);
 
         s = DO_UPCAST(VhostUserState, nc, ncs[i]);
         if (vhost_user_running(s)) {
@@ -163,20 +163,20 @@ static void vhost_user_cleanup(NetClientState *nc)
 
 static bool vhost_user_has_vnet_hdr(NetClientState *nc)
 {
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER);
+    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
 
     return true;
 }
 
 static bool vhost_user_has_ufo(NetClientState *nc)
 {
-    assert(nc->info->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER);
+    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
 
     return true;
 }
 
 static NetClientInfo net_vhost_user_info = {
-        .type = NET_CLIENT_OPTIONS_KIND_VHOST_USER,
+        .type = NET_CLIENT_DRIVER_VHOST_USER,
         .size = sizeof(VhostUserState),
         .receive = vhost_user_receive,
         .cleanup = vhost_user_cleanup,
@@ -207,7 +207,7 @@ static void net_vhost_user_event(void *opaque, int event)
     int queues;
 
     queues = qemu_find_net_clients_except(name, ncs,
-                                          NET_CLIENT_OPTIONS_KIND_NIC,
+                                          NET_CLIENT_DRIVER_NIC,
                                           MAX_QUEUE_NUM);
     assert(queues < MAX_QUEUE_NUM);
 
@@ -341,8 +341,8 @@ int net_init_vhost_user(const Netdev *netdev, const char *name,
     const NetdevVhostUserOptions *vhost_user_opts;
     CharDriverState *chr;
 
-    assert(netdev->opts->type == NET_CLIENT_OPTIONS_KIND_VHOST_USER);
-    vhost_user_opts = netdev->opts->u.vhost_user.data;
+    assert(netdev->type == NET_CLIENT_DRIVER_VHOST_USER);
+    vhost_user_opts = &netdev->u.vhost_user;
 
     chr = net_vhost_parse_chardev(vhost_user_opts, errp);
     if (!chr) {