[PATCH v9 01/10] migration: New QAPI type 'MigrateAddress'

[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 type string. The current implementation follows
double encoding scheme for fetching migration parameters like
'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.

Note: this commit only adds the type, and actual uses comes
in later commits.

Suggested-by: Aravind Retnakaran <aravind.retnakaran@nutanix.com>
Signed-off-by: Het Gala <het.gala@nutanix.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
---
 qapi/migration.json | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/qapi/migration.json b/qapi/migration.json
index 47dfef0278..0f4a54a7ed 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1417,6 +1417,47 @@
 ##
 { 'command': 'migrate-continue', 'data': {'state': 'MigrationStatus'} }
 
+##
+# @MigrationAddressType:
+#
+# The migration stream transport mechanisms.
+#
+# @socket: Migrate via socket.
+#
+# @exec: Direct the migration stream to another process.
+#
+# @rdma: Migrate via RDMA.
+#
+# Since 8.2
+##
+{ 'enum': 'MigrationAddressType',
+  'data': ['socket', 'exec', 'rdma'] }
+
+##
+# @MigrationExecCommand:
+#
+# @args: command (list head) and arguments to execute.
+#
+# Since 8.2
+##
+{ 'struct': 'MigrationExecCommand',
+  'data': {'args': [ 'str' ] } }
+
+##
+# @MigrationAddress:
+#
+# Migration endpoint configuration.
+#
+# Since 8.2
+##
+{ 'union': 'MigrationAddress',
+  'base': { 'transport' : 'MigrationAddressType'},
+  'discriminator': 'transport',
+  'data': {
+    'socket': 'SocketAddress',
+    'exec': 'MigrationExecCommand',
+    'rdma': 'InetSocketAddress' } }
+
 ##
 # @migrate:
 #
-- 
2.22.3