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

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

- if 'addr' is provided with -device/device_add command, attempt to
use it or fail command if it's already occupied or falls inside
of an existing PCDIMMDevice memory region.

Note:
GCompareFunc(a, b) used by g_slist_insert_sorted() returns 'gint',
however it might be too small to fit difference between
2 addresses. So use 128bit to calculate the difference and normalize
result to -1/0/1 return values.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Andrey Korolyov <andrey@xdel.ru>

MST: commit log tweaks

1 files changed, 9 insertions, 0 deletions

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 70527d8880..4dc86d5bc4 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -1558,6 +1558,15 @@ static void pc_dimm_plug(HotplugHandler *hotplug_dev,
         goto out;
     }
 
+    addr = pc_dimm_get_free_addr(pcms->hotplug_memory_base,
+                                 memory_region_size(&pcms->hotplug_memory),
+                                 !addr ? NULL : &addr,
+                                 memory_region_size(mr), &local_err);
+    if (local_err) {
+        goto out;
+    }
+    object_property_set_int(OBJECT(dev), addr, PC_DIMM_ADDR_PROP, &local_err);
+
     memory_region_add_subregion(&pcms->hotplug_memory,
                                 addr - pcms->hotplug_memory_base, mr);
     vmstate_register_ram(mr, dev);