[PATCH v5 6/6] qapi/device_add: Allow execution in machine initialized phase

[Damien Hedde <damien.hedde@greensocs.com>]

From: Mirela Grujic <mirela.grujic@greensocs.com>

This commit allows to use the QMP command to add a cold-plugged
device like we can do with the CLI option -device.

Note: for device_add command in qdev.json adding the 'allow-preconfig'
option has no effect because the command appears to bypass QAPI (see
TODO at qapi/qdev.json:61). The option is added there solely to
document the intent.
For the same reason, the flags have to be explicitly set in
monitor_init_qmp_commands() when the device_add command is registered.

Signed-off-by: Mirela Grujic <mirela.grujic@greensocs.com>
Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
---

v4:
 + use phase_until()
 + add missing flag in hmp-commands.hx
---
 qapi/qdev.json         | 3 ++-
 monitor/misc.c         | 2 +-
 softmmu/qdev-monitor.c | 4 ++++
 hmp-commands.hx        | 1 +
 4 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/qapi/qdev.json b/qapi/qdev.json
index 26cd10106b..2e2de41499 100644
--- a/qapi/qdev.json
+++ b/qapi/qdev.json
@@ -77,7 +77,8 @@
 { 'command': 'device_add',
   'data': {'driver': 'str', '*bus': 'str', '*id': 'str'},
   'gen': false, # so we can get the additional arguments
-  'features': ['json-cli', 'json-cli-hotplug'] }
+  'features': ['json-cli', 'json-cli-hotplug'],
+  'allow-preconfig': true }
 
 ##
 # @device_del:
diff --git a/monitor/misc.c b/monitor/misc.c
index 6c5bb82d3b..d3d413d70c 100644
--- a/monitor/misc.c
+++ b/monitor/misc.c
@@ -233,7 +233,7 @@ static void monitor_init_qmp_commands(void)
     qmp_init_marshal(&qmp_commands);
 
     qmp_register_command(&qmp_commands, "device_add",
-                         qmp_device_add, 0, 0);
+                         qmp_device_add, QCO_ALLOW_PRECONFIG, 0);
 
     QTAILQ_INIT(&qmp_cap_negotiation_commands);
     qmp_register_command(&qmp_cap_negotiation_commands, "qmp_capabilities",
diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c
index 7cbee2b0d8..c53f62be51 100644
--- a/softmmu/qdev-monitor.c
+++ b/softmmu/qdev-monitor.c
@@ -855,6 +855,10 @@ void qmp_device_add(QDict *qdict, QObject **ret_data, Error **errp)
     QemuOpts *opts;
     DeviceState *dev;
 
+    if (!phase_until(PHASE_MACHINE_INITIALIZED, errp)) {
+        return;
+    }
+
     opts = qemu_opts_from_qdict(qemu_find_opts("device"), qdict, errp);
     if (!opts) {
         return;
diff --git a/hmp-commands.hx b/hmp-commands.hx
index 03e6a73d1f..0091b8e2dd 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -672,6 +672,7 @@ ERST
         .help       = "add device, like -device on the command line",
         .cmd        = hmp_device_add,
         .command_completion = device_add_completion,
+        .flags      = "p",
     },
 
 SRST
-- 
2.36.1