Property will contain link to memory backend that will be
used for backing initial RAM.
Follow up commit will alias -mem-path and -mem-prealloc
CLI options into memory backend options to make memory
handling consistent (using only hostmem backend family
for guest RAM allocation).

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
v3:
 * rename property name from ram-memdev to memory-backend
   (Paolo Bonzini <pbonzini@redhat.com>)

CC: ehabkost@redhat.com
CC: pbonzini@redhat.com
---
 include/hw/boards.h | 2 ++
 hw/core/machine.c   | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/include/hw/boards.h b/include/hw/boards.h
index fb1b43d..6aa01b8 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -4,6 +4,7 @@
 #define HW_BOARDS_H
 
 #include "exec/memory.h"
+#include "sysemu/hostmem.h"
 #include "sysemu/blockdev.h"
 #include "sysemu/accel.h"
 #include "qapi/qapi-types-machine.h"
@@ -285,6 +286,7 @@ struct MachineState {
     bool enforce_config_section;
     bool enable_graphics;
     char *memory_encryption;
+    HostMemoryBackend *ram_memdev;
     DeviceMemoryState *device_memory;
 
     ram_addr_t ram_size;
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 3e288bf..bf30183 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -886,6 +886,15 @@ static void machine_initfn(Object *obj)
                                         "Table (HMAT)", NULL);
     }
 
+    object_property_add_link(obj, "memory-backend", TYPE_MEMORY_BACKEND,
+                             (Object **)&ms->ram_memdev,
+                             object_property_allow_set_link,
+                             OBJ_PROP_LINK_STRONG, &error_abort);
+    object_property_set_description(obj, "memory-backend",
+                                    "Set RAM backend"
+                                    "Valid value is ID of hostmem based backend",
+                                     &error_abort);
+
     /* Register notifier when init is done for sysbus sanity checks */
     ms->sysbus_notifier.notify = machine_init_notify;
     qemu_add_machine_init_done_notifier(&ms->sysbus_notifier);
-- 
2.7.4