[Qemu-devel] [PATCH 2/2] memory-backend: Add can_be_deleted impl for ram-backend and file-backend

[Lin Ma <lma@suse.com>]

The can_be_deleted callback returns false if the backend is in used,
Otherwise returns true.

Signed-off-by: Lin Ma <lma@suse.com>
---
 backends/hostmem-file.c | 12 ++++++++++++
 backends/hostmem-ram.c  | 12 ++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c
index 5179994..33ad8e7 100644
--- a/backends/hostmem-file.c
+++ b/backends/hostmem-file.c
@@ -118,10 +118,22 @@ file_backend_instance_init(Object *o)
                             set_mem_path, NULL);
 }
 
+static bool
+file_backend_can_be_deleted(Object *obj)
+{
+    MemoryRegion *mr;
+    mr = host_memory_backend_get_memory(MEMORY_BACKEND(obj), &error_abort);
+    if (memory_region_is_mapped(mr))
+        return false;
+    else
+        return true;
+}
+
 static const TypeInfo file_backend_info = {
     .name = TYPE_MEMORY_BACKEND_FILE,
     .parent = TYPE_MEMORY_BACKEND,
     .class_init = file_backend_class_init,
+    .can_be_deleted = file_backend_can_be_deleted,
     .instance_init = file_backend_instance_init,
     .instance_size = sizeof(HostMemoryBackendFile),
 };
diff --git a/backends/hostmem-ram.c b/backends/hostmem-ram.c
index a67a134..8724ad1 100644
--- a/backends/hostmem-ram.c
+++ b/backends/hostmem-ram.c
@@ -39,10 +39,22 @@ ram_backend_class_init(ObjectClass *oc, void *data)
     bc->alloc = ram_backend_memory_alloc;
 }
 
+static bool
+ram_backend_can_be_deleted(Object *obj)
+{
+    MemoryRegion *mr;
+    mr = host_memory_backend_get_memory(MEMORY_BACKEND(obj), &error_abort);
+    if (memory_region_is_mapped(mr))
+        return false;
+    else
+        return true;
+}
+
 static const TypeInfo ram_backend_info = {
     .name = TYPE_MEMORY_BACKEND_RAM,
     .parent = TYPE_MEMORY_BACKEND,
     .class_init = ram_backend_class_init,
+    .can_be_deleted = ram_backend_can_be_deleted,
 };
 
 static void register_types(void)
-- 
2.1.4