[Qemu-devel] [PATCH v4 4/8] hw/arm/virt: Add memory hotplug framework

[Shameer Kolothum]

From: Eric Auger <eric.au...@redhat.com>

This patch adds the memory hot-plug/hot-unplug infrastructure
in machvirt. The device memory is not yet exposed to the Guest
either though DT or ACPI and hence both cold/hot plug of memory
is explicitly disabled for now.

Signed-off-by: Eric Auger <eric.au...@redhat.com>
Signed-off-by: Kwangwoo Lee <kwangwoo....@sk.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.th...@huawei.com>
---
 default-configs/arm-softmmu.mak |  3 +++
 hw/arm/virt.c                   | 45 ++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
index 613d19a..9f4b803 100644
--- a/default-configs/arm-softmmu.mak
+++ b/default-configs/arm-softmmu.mak
@@ -160,3 +160,6 @@ CONFIG_MUSICPAL=y
 
 # for realview and versatilepb
 CONFIG_LSI_SCSI_PCI=y
+
+CONFIG_MEM_DEVICE=y
+CONFIG_DIMM=y
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index ce2664a..da516b3 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -61,6 +61,8 @@
 #include "hw/arm/smmuv3.h"
 #include "hw/acpi/acpi.h"
 #include "target/arm/internals.h"
+#include "hw/mem/pc-dimm.h"
+#include "hw/mem/nvdimm.h"
 
 #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
     static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
@@ -1806,6 +1808,34 @@ static const CPUArchIdList 
*virt_possible_cpu_arch_ids(MachineState *ms)
     return ms->possible_cpus;
 }
 
+static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
+                                 Error **errp)
+{
+    if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
+        error_setg(errp, "memory cold/hot plug is not yet supported");
+        return;
+    }
+
+    pc_dimm_pre_plug(PC_DIMM(dev), MACHINE(hotplug_dev), NULL, errp);
+}
+
+static void virt_memory_plug(HotplugHandler *hotplug_dev,
+                             DeviceState *dev, Error **errp)
+{
+    VirtMachineState *vms = VIRT_MACHINE(hotplug_dev);
+
+    pc_dimm_plug(PC_DIMM(dev), MACHINE(vms), NULL);
+
+}
+
+static void virt_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
+                                            DeviceState *dev, Error **errp)
+{
+    if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
+        virt_memory_pre_plug(hotplug_dev, dev, errp);
+    }
+}
+
 static void virt_machine_device_plug_cb(HotplugHandler *hotplug_dev,
                                         DeviceState *dev, Error **errp)
 {
@@ -1817,12 +1847,23 @@ static void virt_machine_device_plug_cb(HotplugHandler 
*hotplug_dev,
                                      SYS_BUS_DEVICE(dev));
         }
     }
+    if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
+        virt_memory_plug(hotplug_dev, dev, errp);
+    }
+}
+
+static void virt_machine_device_unplug_request_cb(HotplugHandler *hotplug_dev,
+                                          DeviceState *dev, Error **errp)
+{
+    error_setg(errp, "device unplug request for unsupported device"
+               " type: %s", object_get_typename(OBJECT(dev)));
 }
 
 static HotplugHandler *virt_machine_get_hotplug_handler(MachineState *machine,
                                                         DeviceState *dev)
 {
-    if (object_dynamic_cast(OBJECT(dev), TYPE_SYS_BUS_DEVICE)) {
+    if (object_dynamic_cast(OBJECT(dev), TYPE_SYS_BUS_DEVICE) ||
+       (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM))) {
         return HOTPLUG_HANDLER(machine);
     }
 
@@ -1886,7 +1927,9 @@ static void virt_machine_class_init(ObjectClass *oc, void 
*data)
     mc->kvm_type = virt_kvm_type;
     assert(!mc->get_hotplug_handler);
     mc->get_hotplug_handler = virt_machine_get_hotplug_handler;
+    hc->pre_plug = virt_machine_device_pre_plug_cb;
     hc->plug = virt_machine_device_plug_cb;
+    hc->unplug_request = virt_machine_device_unplug_request_cb;
 }
 
 static void virt_instance_init(Object *obj)
-- 
2.7.4