pc-dimm: add busy slot check and slot auto-allocation

- if slot property is not specified on -device/device_add command,
treat default value as request for assigning PCDIMMDevice to
the first free slot.

- if slot is provided with -device/device_add command, attempt to
use it or fail command if it's already occupied.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 21 insertions, 0 deletions

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 4dc86d5bc4..be5e3bbafd 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1547,8 +1547,10 @@ void qemu_register_pc_machine(QEMUMachine *m)
 static void pc_dimm_plug(HotplugHandler *hotplug_dev,
                          DeviceState *dev, Error **errp)
 {
+    int slot;
     Error *local_err = NULL;
     PCMachineState *pcms = PC_MACHINE(hotplug_dev);
+    MachineState *machine = MACHINE(hotplug_dev);
     PCDIMMDevice *dimm = PC_DIMM(dev);
     PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
     MemoryRegion *mr = ddc->get_memory_region(dimm);
@@ -1565,7 +1567,26 @@ static void pc_dimm_plug(HotplugHandler *hotplug_dev,
     if (local_err) {
         goto out;
     }
+
     object_property_set_int(OBJECT(dev), addr, PC_DIMM_ADDR_PROP, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    slot = pc_dimm_get_free_slot(slot == PC_DIMM_UNASSIGNED_SLOT ? NULL : &slot,
+                                 machine->ram_slots, &local_err);
+    if (local_err) {
+        goto out;
+    }
+    object_property_set_int(OBJECT(dev), slot, PC_DIMM_SLOT_PROP, &local_err);
+    if (local_err) {
+        goto out;
+    }
 
     memory_region_add_subregion(&pcms->hotplug_memory,
                                 addr - pcms->hotplug_memory_base, mr);