qapi: add conditions to REPLICATION type/commands on the schema

Add #if defined(CONFIG_REPLICATION) in generated code, and adjust the
code accordingly.

Made conditional:

* xen-set-replication, query-xen-replication-status,
  xen-colo-do-checkpoint

  Before the patch, we first register the commands unconditionally in
  generated code (requires a stub), then conditionally unregister in
  qmp_unregister_commands_hack().

  Afterwards, we register only when CONFIG_REPLICATION.  The command
  fails exactly the same, with CommandNotFound.

  Improvement, because now query-qmp-schema is accurate, and we're one
  step closer to killing qmp_unregister_commands_hack().

* enum BlockdevDriver value "replication" in command blockdev-add

* BlockdevOptions variant @replication

and related structures.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181213123724.4866-23-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

migration/colo.c

@@ -24,7 +24,9 @@
 #include "trace.h"
 #include "qemu/error-report.h"
 #include "migration/failover.h"
+#ifdef CONFIG_REPLICATION
 #include "replication.h"
+#endif
 #include "net/colo-compare.h"
 #include "net/colo.h"
 #include "block/block.h"
@@ -201,11 +203,11 @@ void colo_do_failover(MigrationState *s)
     }
 }
 
+#ifdef CONFIG_REPLICATION
 void qmp_xen_set_replication(bool enable, bool primary,
                              bool has_failover, bool failover,
                              Error **errp)
 {
-#ifdef CONFIG_REPLICATION
     ReplicationMode mode = primary ?
                            REPLICATION_MODE_PRIMARY :
                            REPLICATION_MODE_SECONDARY;
@@ -224,14 +226,10 @@ void qmp_xen_set_replication(bool enable, bool primary,
         }
         replication_stop_all(failover, failover ? NULL : errp);
     }
-#else
-    abort();
-#endif
 }
 
 ReplicationStatus *qmp_query_xen_replication_status(Error **errp)
 {
-#ifdef CONFIG_REPLICATION
     Error *err = NULL;
     ReplicationStatus *s = g_new0(ReplicationStatus, 1);
 
@@ -246,19 +244,13 @@ ReplicationStatus *qmp_query_xen_replication_status(Error **errp)
 
     error_free(err);
     return s;
-#else
-    abort();
-#endif
 }
 
 void qmp_xen_colo_do_checkpoint(Error **errp)
 {
-#ifdef CONFIG_REPLICATION
     replication_do_checkpoint_all(errp);
-#else
-    abort();
-#endif
 }
+#endif
 
 COLOStatus *qmp_query_colo_status(Error **errp)
 {

monitor.c

@@ -1147,11 +1147,6 @@ static void qmp_query_qmp_schema(QDict *qdict, QObject **ret_data,
  */
 static void qmp_unregister_commands_hack(void)
 {
-#ifndef CONFIG_REPLICATION
-    qmp_unregister_command(&qmp_commands, "xen-set-replication");
-    qmp_unregister_command(&qmp_commands, "query-xen-replication-status");
-    qmp_unregister_command(&qmp_commands, "xen-colo-do-checkpoint");
-#endif
 #ifndef TARGET_I386
     qmp_unregister_command(&qmp_commands, "rtc-reset-reinjection");
     qmp_unregister_command(&qmp_commands, "query-sev");

qapi/block-core.json

@@ -2623,7 +2623,9 @@
             'copy-on-read', 'dmg', 'file', 'ftp', 'ftps', 'gluster',
             'host_cdrom', 'host_device', 'http', 'https', 'iscsi', 'luks',
             'nbd', 'nfs', 'null-aio', 'null-co', 'nvme', 'parallels', 'qcow',
-            'qcow2', 'qed', 'quorum', 'raw', 'rbd', 'replication', 'sheepdog',
+            'qcow2', 'qed', 'quorum', 'raw', 'rbd',
+            { 'name': 'replication', 'if': 'defined(CONFIG_REPLICATION)' },
+            'sheepdog',
             'ssh', 'throttle', 'vdi', 'vhdx', 'vmdk', 'vpc', 'vvfat', 'vxhs' ] }
 
 ##
@@ -3380,7 +3382,8 @@
 #
 # Since: 2.9
 ##
-{ 'enum' : 'ReplicationMode', 'data' : [ 'primary', 'secondary' ] }
+{ 'enum' : 'ReplicationMode', 'data' : [ 'primary', 'secondary' ],
+  'if': 'defined(CONFIG_REPLICATION)' }
 
 ##
 # @BlockdevOptionsReplication:
@@ -3398,7 +3401,8 @@
 { 'struct': 'BlockdevOptionsReplication',
   'base': 'BlockdevOptionsGenericFormat',
   'data': { 'mode': 'ReplicationMode',
-            '*top-id': 'str' } }
+            '*top-id': 'str' },
+  'if': 'defined(CONFIG_REPLICATION)' }
 
 ##
 # @NFSTransport:
@@ -3714,7 +3718,8 @@
       'quorum':     'BlockdevOptionsQuorum',
       'raw':        'BlockdevOptionsRaw',
       'rbd':        'BlockdevOptionsRbd',
-      'replication':'BlockdevOptionsReplication',
+      'replication': { 'type': 'BlockdevOptionsReplication',
+                       'if': 'defined(CONFIG_REPLICATION)' },
       'sheepdog':   'BlockdevOptionsSheepdog',
       'ssh':        'BlockdevOptionsSsh',
       'throttle':   'BlockdevOptionsThrottle',

qapi/migration.json

@@ -1257,7 +1257,8 @@
 # Since: 2.9
 ##
 { 'command': 'xen-set-replication',
-  'data': { 'enable': 'bool', 'primary': 'bool', '*failover' : 'bool' } }
+  'data': { 'enable': 'bool', 'primary': 'bool', '*failover' : 'bool' },
+  'if': 'defined(CONFIG_REPLICATION)' }
 
 ##
 # @ReplicationStatus:
@@ -1272,7 +1273,8 @@
 # Since: 2.9
 ##
 { 'struct': 'ReplicationStatus',
-  'data': { 'error': 'bool', '*desc': 'str' } }
+  'data': { 'error': 'bool', '*desc': 'str' },
+  'if': 'defined(CONFIG_REPLICATION)' }
 
 ##
 # @query-xen-replication-status:
@@ -1289,7 +1291,8 @@
 # Since: 2.9
 ##
 { 'command': 'query-xen-replication-status',
-  'returns': 'ReplicationStatus' }
+  'returns': 'ReplicationStatus',
+  'if': 'defined(CONFIG_REPLICATION)' }
 
 ##
 # @xen-colo-do-checkpoint:
@@ -1305,7 +1308,8 @@
 #
 # Since: 2.9
 ##
-{ 'command': 'xen-colo-do-checkpoint' }
+{ 'command': 'xen-colo-do-checkpoint',
+  'if': 'defined(CONFIG_REPLICATION)' }
 
 ##
 # @COLOStatus: