pc: factor out pc specific dimm checks into pc_memory_pre_plug()

We can perform these checks before the device is actually realized.
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NIgor Mammedov <imammedo@redhat.com>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20180619134141.29478-6-david@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

hw/i386/pc.c

@@ -1674,6 +1674,29 @@ void ioapic_init_gsi(GSIState *gsi_state, const char *parent_name)
     }
 }
 
+static void pc_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
+                               Error **errp)
+{
+    const PCMachineState *pcms = PC_MACHINE(hotplug_dev);
+    const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
+
+    /*
+     * When -no-acpi is used with Q35 machine type, no ACPI is built,
+     * but pcms->acpi_dev is still created. Check !acpi_enabled in
+     * addition to cover this case.
+     */
+    if (!pcms->acpi_dev || !acpi_enabled) {
+        error_setg(errp,
+                   "memory hotplug is not enabled: missing acpi device or acpi disabled");
+        return;
+    }
+
+    if (is_nvdimm && !pcms->acpi_nvdimm_state.is_enabled) {
+        error_setg(errp, "nvdimm is not enabled: missing 'nvdimm' in '-M'");
+        return;
+    }
+}
+
 static void pc_memory_plug(HotplugHandler *hotplug_dev,
                            DeviceState *dev, Error **errp)
 {
@@ -1696,23 +1719,6 @@ static void pc_memory_plug(HotplugHandler *hotplug_dev,
         align = memory_region_get_alignment(mr);
     }
 
-    /*
-     * When -no-acpi is used with Q35 machine type, no ACPI is built,
-     * but pcms->acpi_dev is still created. Check !acpi_enabled in
-     * addition to cover this case.
-     */
-    if (!pcms->acpi_dev || !acpi_enabled) {
-        error_setg(&local_err,
-                   "memory hotplug is not enabled: missing acpi device or acpi disabled");
-        goto out;
-    }
-
-    if (is_nvdimm && !pcms->acpi_nvdimm_state.is_enabled) {
-        error_setg(&local_err,
-                   "nvdimm is not enabled: missing 'nvdimm' in '-M'");
-        goto out;
-    }
-
     pc_dimm_plug(dev, MACHINE(pcms), align, &local_err);
     if (local_err) {
         goto out;
@@ -2006,7 +2012,9 @@ static void pc_cpu_pre_plug(HotplugHandler *hotplug_dev,
 static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
                                           DeviceState *dev, Error **errp)
 {
-    if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
+    if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
+        pc_memory_pre_plug(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_pre_plug(hotplug_dev, dev, errp);
     }
 }