[PATCH v3 2/2] net: Drop the NetLegacy structure, always use Netdev instead

[Thomas Huth]

Now that the "name" parameter is gone, there is hardly any difference
between NetLegacy and Netdev anymore, so we can drop NetLegacy and always
use Netdev to simplify the code quite a bit.

The only two differences that were really left between Netdev and NetLegacy:

1) NetLegacy does not allow a "hubport" type. We can continue to block
   this with a simple check in net_client_init1() for this type.

2) The "id" parameter was optional in NetLegacy (and an internal id
   was chosen via assign_name() during initialization), but it is mandatory
   for Netdev. To avoid that the visitor code bails out here, we have to
   add an internal id to the QemuOpts already earlier now.

Signed-off-by: Thomas Huth <address@hidden>
---
 Note: I did not rename the "is_netdev" parameter of the function (as
 Eric suggested) - you really have to think of "-netdev" vs. "-net"
 here and not about "Netdev" vs. "NetLegacy". But if this "is_netdev"
 thing still confuses us in the future, we can still rename it with an
 additional follow-up patch later instead.

 net/net.c     | 77 +++++++++------------------------------------------
 qapi/net.json | 46 ------------------------------
 2 files changed, 13 insertions(+), 110 deletions(-)

diff --git a/net/net.c b/net/net.c
index a24da66e66..d4cc5bd73e 100644
--- a/net/net.c
+++ b/net/net.c
@@ -965,15 +965,11 @@ static int (* const 
net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
 };
 
 
-static int net_client_init1(const void *object, bool is_netdev, Error **errp)
+static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
 {
-    Netdev legacy = {0};
-    const Netdev *netdev;
     NetClientState *peer = NULL;
 
     if (is_netdev) {
-        netdev = object;
-
         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
             !net_client_init_fun[netdev->type]) {
             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
@@ -981,56 +977,11 @@ static int net_client_init1(const void *object, bool 
is_netdev, Error **errp)
             return -1;
         }
     } else {
-        const NetLegacy *net = object;
-        const NetLegacyOptions *opts = net->opts;
-        legacy.id = net->id;
-        netdev = &legacy;
-
-        /* Map the old options to the new flat type */
-        switch (opts->type) {
-        case NET_LEGACY_OPTIONS_TYPE_NONE:
+        if (netdev->type == NET_CLIENT_DRIVER_NONE) {
             return 0; /* nothing to do */
-        case NET_LEGACY_OPTIONS_TYPE_NIC:
-            legacy.type = NET_CLIENT_DRIVER_NIC;
-            legacy.u.nic = opts->u.nic;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_USER:
-            legacy.type = NET_CLIENT_DRIVER_USER;
-            legacy.u.user = opts->u.user;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_TAP:
-            legacy.type = NET_CLIENT_DRIVER_TAP;
-            legacy.u.tap = opts->u.tap;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_L2TPV3:
-            legacy.type = NET_CLIENT_DRIVER_L2TPV3;
-            legacy.u.l2tpv3 = opts->u.l2tpv3;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_SOCKET:
-            legacy.type = NET_CLIENT_DRIVER_SOCKET;
-            legacy.u.socket = opts->u.socket;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_VDE:
-            legacy.type = NET_CLIENT_DRIVER_VDE;
-            legacy.u.vde = opts->u.vde;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_BRIDGE:
-            legacy.type = NET_CLIENT_DRIVER_BRIDGE;
-            legacy.u.bridge = opts->u.bridge;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_NETMAP:
-            legacy.type = NET_CLIENT_DRIVER_NETMAP;
-            legacy.u.netmap = opts->u.netmap;
-            break;
-        case NET_LEGACY_OPTIONS_TYPE_VHOST_USER:
-            legacy.type = NET_CLIENT_DRIVER_VHOST_USER;
-            legacy.u.vhost_user = opts->u.vhost_user;
-            break;
-        default:
-            abort();
         }
-
-        if (!net_client_init_fun[netdev->type]) {
+        if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
+            !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)");
@@ -1039,7 +990,7 @@ static int net_client_init1(const void *object, bool 
is_netdev, Error **errp)
 
         /* Do not add to a hub if it's a nic with a netdev= parameter. */
         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
-            !opts->u.nic.has_netdev) {
+            !netdev->u.nic.has_netdev) {
             peer = net_hub_add_port(0, NULL, NULL);
         }
     }
@@ -1100,7 +1051,7 @@ static void show_netdevs(void)
 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
 {
     gchar **substrings = NULL;
-    void *object = NULL;
+    Netdev *object = NULL;
     Error *err = NULL;
     int ret = -1;
     Visitor *v = opts_visitor_new(opts);
@@ -1143,21 +1094,19 @@ static int net_client_init(QemuOpts *opts, bool 
is_netdev, Error **errp)
         }
     }
 
-    if (is_netdev) {
-        visit_type_Netdev(v, NULL, (Netdev **)&object, &err);
-    } else {
-        visit_type_NetLegacy(v, NULL, (NetLegacy **)&object, &err);
+    /* Create an ID for -net if the user did not specify one */
+    if (!is_netdev && !qemu_opts_id(opts)) {
+        static int idx;
+        qemu_opts_set_id(opts, g_strdup_printf("__org.qemu.net%i", idx++));
     }
 
+    visit_type_Netdev(v, NULL, &object, &err);
+
     if (!err) {
         ret = net_client_init1(object, is_netdev, &err);
     }
 
-    if (is_netdev) {
-        qapi_free_Netdev(object);
-    } else {
-        qapi_free_NetLegacy(object);
-    }
+    qapi_free_Netdev(object);
 
 out:
     error_propagate(errp, err);
diff --git a/qapi/net.json b/qapi/net.json
index fc7c95f6d8..9244c9af56 100644
--- a/qapi/net.json
+++ b/qapi/net.json
@@ -467,52 +467,6 @@
     'netmap':   'NetdevNetmapOptions',
     'vhost-user': 'NetdevVhostUserOptions' } }
 
-##
-# @NetLegacy:
-#
-# Captures the configuration of a network device; legacy.
-#
-# @id: identifier for monitor commands
-#
-# @opts: device type specific properties (legacy)
-#
-# Since: 1.2
-##
-{ 'struct': 'NetLegacy',
-  'data': {
-    '*id':   'str',
-    'opts':  'NetLegacyOptions' } }
-
-##
-# @NetLegacyOptionsType:
-#
-# Since: 1.2
-##
-{ 'enum': 'NetLegacyOptionsType',
-  'data': ['none', 'nic', 'user', 'tap', 'l2tpv3', 'socket', 'vde',
-           'bridge', 'netmap', 'vhost-user'] }
-
-##
-# @NetLegacyOptions:
-#
-# Like Netdev, but for use only by the legacy command line options
-#
-# Since: 1.2
-##
-{ 'union': 'NetLegacyOptions',
-  'base': { 'type': 'NetLegacyOptionsType' },
-  'discriminator': 'type',
-  'data': {
-    'nic':      'NetLegacyNicOptions',
-    'user':     'NetdevUserOptions',
-    'tap':      'NetdevTapOptions',
-    'l2tpv3':   'NetdevL2TPv3Options',
-    'socket':   'NetdevSocketOptions',
-    'vde':      'NetdevVdeOptions',
-    'bridge':   'NetdevBridgeOptions',
-    'netmap':   'NetdevNetmapOptions',
-    'vhost-user': 'NetdevVhostUserOptions' } }
-
 ##
 # @NetFilterDirection:
 #
-- 
2.18.1