[PATCH v4 1/8] migration: introduced 'MigrateAddress' in QAPI for migration wire protocol.

[Het Gala]

This patch introduces well defined MigrateAddress struct and its related child
objects.

The existing argument of 'migrate' and 'migrate-incoming' QAPI - 'uri' is of
string type. The current migration flow follows double encoding scheme for
fetching migration parameters such as 'uri' and this is not an ideal design.

Motive for intoducing struct level design is to prevent double encoding of QAPI
arguments, as Qemu should be able to directly use the QAPI arguments without
any level of encoding.

Suggested-by: Aravind Retnakaran <aravind.retnakaran@nutanix.com>
Signed-off-by: Het Gala <het.gala@nutanix.com>
---
 qapi/migration.json | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/qapi/migration.json b/qapi/migration.json
index 82000adce4..bf90bd8fe2 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1423,6 +1423,47 @@
 ##
 { 'command': 'migrate-continue', 'data': {'state': 'MigrationStatus'} }
 
+##
+# @MigrateTransport:
+#
+# The supported communication transport mechanisms for migration
+#
+# @socket: Supported communication type between two devices for migration.
+#          Socket is able to cover all of 'tcp', 'unix', 'vsock' and
+#          'fd' already
+#
+# @exec: Supported communication type to redirect migration stream into file.
+#
+# @rdma: Supported communication type to redirect rdma type migration stream.
+#
+# Since 8.0
+##
+{ 'enum': 'MigrateTransport',
+  'data': ['socket', 'exec', 'rdma'] }
+
+##
+# @MigrateExecCommand:
+ #
+ # Since 8.0
+ ##
+{ 'struct': 'MigrateExecCommand',
+   'data': {'args': [ 'str' ] } }
+
+##
+# @MigrateAddress:
+#
+# The options available for communication transport mechanisms for migration
+#
+# Since 8.0
+##
+{ 'union': 'MigrateAddress',
+  'base': { 'transport' : 'MigrateTransport'},
+  'discriminator': 'transport',
+  'data': {
+    'socket': 'SocketAddress',
+    'exec': 'MigrateExecCommand',
+    'rdma': 'InetSocketAddress' } }
+
 ##
 # @migrate:
 #
-- 
2.22.3