[Qemu-devel] [PATCH v2 2/3] qapi: change NetLegacy into a flat union

[Kővágó, Zoltán]

This is required to keep backward compatibility while applying the
proposed changes to OptsVisitor in the next commit.

Strictly speaking this change breaks QMP compatibility, but since this
struct is only used by the (legacy) -net option, it's not a problem.
(The command line syntax doesn't change.)

Signed-off-by: Kővágó, Zoltán <address@hidden>
---
 net/net.c        | 47 +++++++++++++++++++++++------------------------
 qapi-schema.json | 29 +++++++++++++++++++++--------
 2 files changed, 44 insertions(+), 32 deletions(-)

diff --git a/net/net.c b/net/net.c
index 69456b2..8ae1cd8 100644
--- a/net/net.c
+++ b/net/net.c
@@ -931,55 +931,54 @@ static int net_client_init1(const void *object, bool 
is_netdev, Error **errp)
         }
     } else {
         const NetLegacy *net = object;
-        const NetClientOptions *opts = net->opts;
         legacy.id = net->id;
         netdev = &legacy;
         /* missing optional values have been initialized to "all bits zero" */
         name = net->has_id ? net->id : net->name;
 
         /* Map the old options to the new flat type */
-        switch (opts->type) {
-        case NET_CLIENT_OPTIONS_KIND_NONE:
+        switch (net->type) {
+        case NET_CLIENT_DRIVER_LEGACY_NONE:
             return 0; /* nothing to do */
-        case NET_CLIENT_OPTIONS_KIND_NIC:
+        case NET_CLIENT_DRIVER_LEGACY_NIC:
             legacy.type = NET_CLIENT_DRIVER_NIC;
-            legacy.nic = opts->nic;
+            legacy.nic = net->nic;
             break;
-        case NET_CLIENT_OPTIONS_KIND_USER:
+        case NET_CLIENT_DRIVER_LEGACY_USER:
             legacy.type = NET_CLIENT_DRIVER_USER;
-            legacy.user = opts->user;
+            legacy.user = net->user;
             break;
-        case NET_CLIENT_OPTIONS_KIND_TAP:
+        case NET_CLIENT_DRIVER_LEGACY_TAP:
             legacy.type = NET_CLIENT_DRIVER_TAP;
-            legacy.tap = opts->tap;
+            legacy.tap = net->tap;
             break;
-        case NET_CLIENT_OPTIONS_KIND_L2TPV3:
+        case NET_CLIENT_DRIVER_LEGACY_L2TPV3:
             legacy.type = NET_CLIENT_DRIVER_L2TPV3;
-            legacy.l2tpv3 = opts->l2tpv3;
+            legacy.l2tpv3 = net->l2tpv3;
             break;
-        case NET_CLIENT_OPTIONS_KIND_SOCKET:
+        case NET_CLIENT_DRIVER_LEGACY_SOCKET:
             legacy.type = NET_CLIENT_DRIVER_SOCKET;
-            legacy.socket = opts->socket;
+            legacy.socket = net->socket;
             break;
-        case NET_CLIENT_OPTIONS_KIND_VDE:
+        case NET_CLIENT_DRIVER_LEGACY_VDE:
             legacy.type = NET_CLIENT_DRIVER_VDE;
-            legacy.vde = opts->vde;
+            legacy.vde = net->vde;
             break;
-        case NET_CLIENT_OPTIONS_KIND_DUMP:
+        case NET_CLIENT_DRIVER_LEGACY_DUMP:
             legacy.type = NET_CLIENT_DRIVER_DUMP;
-            legacy.dump = opts->dump;
+            legacy.dump = net->dump;
             break;
-        case NET_CLIENT_OPTIONS_KIND_BRIDGE:
+        case NET_CLIENT_DRIVER_LEGACY_BRIDGE:
             legacy.type = NET_CLIENT_DRIVER_BRIDGE;
-            legacy.bridge = opts->bridge;
+            legacy.bridge = net->bridge;
             break;
-        case NET_CLIENT_OPTIONS_KIND_NETMAP:
+        case NET_CLIENT_DRIVER_LEGACY_NETMAP:
             legacy.type = NET_CLIENT_DRIVER_NETMAP;
-            legacy.netmap = opts->netmap;
+            legacy.netmap = net->netmap;
             break;
-        case NET_CLIENT_OPTIONS_KIND_VHOST_USER:
+        case NET_CLIENT_DRIVER_LEGACY_VHOST_USER:
             legacy.type = NET_CLIENT_DRIVER_VHOST_USER;
-            legacy.vhost_user = opts->vhost_user;
+            legacy.vhost_user = net->vhost_user;
             break;
         default:
             abort();
@@ -994,7 +993,7 @@ static int net_client_init1(const void *object, bool 
is_netdev, Error **errp)
 
         /* Do not add to a vlan if it's a nic with a netdev= parameter. */
         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
-            !opts->nic->has_netdev) {
+            !net->nic->has_netdev) {
             peer = net_hub_add_port(net->has_vlan ? net->vlan : 0, NULL);
         }
     }
diff --git a/qapi-schema.json b/qapi-schema.json
index 72827f8..4f9946e 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2531,9 +2531,9 @@
     'vhost-user': 'NetdevVhostUserOptions' } }
 
 ##
-# @NetLegacy
+# @NetLegacyBase
 #
-# Captures the configuration of a network device; legacy.
+# Captures the common configuration of a network device, legacy.
 #
 # @vlan: #optional vlan number
 #
@@ -2541,25 +2541,38 @@
 #
 # @name: #optional identifier for monitor commands, ignored if @id is present
 #
-# @opts: device type specific properties (legacy)
+# @type: specify the driver used for interpreting remaining arguments.
 #
 # Since 1.2
 ##
-{ 'struct': 'NetLegacy',
+{ 'struct': 'NetLegacyBase',
   'data': {
     '*vlan': 'int32',
     '*id':   'str',
     '*name': 'str',
-    'opts':  'NetClientOptions' } }
+    'type':  'NetClientDriverLegacy' } }
 
 ##
-# @NetClientOptions
+# @NetClientDriverLegacy
 #
-# Like Netdev, but for use only by the legacy command line options
+# Available netdev drivers, legacy.
+#
+# Since 2.5
+##
+{'enum': 'NetClientDriverLegacy',
+  'data': [ 'none', 'nic', 'user', 'tap', 'l2tpv3', 'socket', 'vde', 'dump',
+            'bridge', 'netmap', 'vhost-user' ] }
+
+##
+# @NetLegacy
+#
+# Captures the configuration of a network device; legacy.
 #
 # Since 1.2
 ##
-{ 'union': 'NetClientOptions',
+{ 'union': 'NetLegacy',
+  'base': 'NetLegacyBase',
+  'discriminator': 'type',
   'data': {
     'none':     'NetdevNoneOptions',
     'nic':      'NetLegacyNicOptions',
-- 
2.5.2