[Qemu-devel] [PATCH v4 12/12] monitor: Add memory hot unplug support for device_del command.

[Tang Chen <tangchen@cn.fujitsu.com>]

From: Hu Tao <hutao@cn.fujitsu.com>

Implement find_peripheral_device() to find bus-less device, and call it in
qmp_device_del() so that device_del command will be able to remove memory
device.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
---
 qdev-monitor.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/qdev-monitor.c b/qdev-monitor.c
index 5ec6606..63dabd6 100644
--- a/qdev-monitor.c
+++ b/qdev-monitor.c
@@ -51,6 +51,13 @@ static const QDevAlias qdev_alias_table[] = {
     { }
 };
 
+/* Used as the type of parameter opaque in object_child_foreach(). */
+typedef struct QPeripheralDev
+{
+    const char *id;
+    DeviceState *dev;
+} QPeripheralDev;
+
 static const char *qdev_class_get_alias(DeviceClass *dc)
 {
     const char *typename = object_class_get_name(OBJECT_CLASS(dc));
@@ -683,12 +690,51 @@ int do_device_add(Monitor *mon, const QDict *qdict, QObject **ret_data)
     return 0;
 }
 
+static int query_peripheral_device(Object *obj, void *opaque)
+{
+    QPeripheralDev *pdev = (QPeripheralDev *)opaque;
+    DeviceState *dev = (DeviceState *)obj;
+
+    if (!strcmp(pdev->id, dev->id)) {
+        pdev->dev = dev;
+        return 1;
+    }
+
+    return 0;
+}
+
+static DeviceState *find_peripheral_device(const char *id)
+{
+    Object *peripheral = NULL;
+    QPeripheralDev pdev = {
+        .id = id,
+        .dev = NULL
+    };
+
+    peripheral = qdev_get_peripheral();
+    if (!peripheral)
+        return NULL;
+
+    /*
+     * No need to check return value of object_child_foreach() because when
+     * query_peripheral_device() returns, pdev->dev is the device we are 
+     * looking for, or NULL.
+     */
+    object_child_foreach(peripheral, query_peripheral_device, &pdev);
+
+    return pdev.dev;
+}
+
 void qmp_device_del(const char *id, Error **errp)
 {
     DeviceState *dev;
 
     dev = qdev_find_recursive(sysbus_get_default(), id);
     if (!dev) {
+        dev = find_peripheral_device(id);
+    }
+
+    if (!dev) {
         error_set(errp, QERR_DEVICE_NOT_FOUND, id);
         return;
     }
-- 
1.8.4.2