2 files changed, 23 insertions, 2 deletions
diff --git a/kapi/include/kapi/memory.hpp b/kapi/include/kapi/memory.hpp
index 3ad5ac5..3daaa86 100644
--- a/kapi/include/kapi/memory.hpp
+++ b/kapi/include/kapi/memory.hpp
@@ -1,11 +1,13 @@
 #ifndef TEACHOS_KAPI_MEMORY_HPP
 #define TEACHOS_KAPI_MEMORY_HPP
 
-#include "kapi/memory/address.hpp"  // IWYU pragma: export
-#include "kapi/memory/frame.hpp"    // IWYU pragma: export
+#include "kapi/memory/address.hpp"          // IWYU pragma: export
+#include "kapi/memory/frame.hpp"            // IWYU pragma: export
+#include "kapi/memory/frame_allocator.hpp"  // IWYU pragma: export
 
 namespace teachos::memory
 {
+  auto active_allocator() -> frame_allocator &;
   auto init() -> void;
 }  // namespace teachos::memory
 
diff --git a/kapi/include/kapi/memory/frame_allocator.hpp b/kapi/include/kapi/memory/frame_allocator.hpp
new file mode 100644
index 0000000..f9393ee
--- /dev/null
+++ b/kapi/include/kapi/memory/frame_allocator.hpp
@@ -0,0 +1,19 @@
+#ifndef TEACHOS_KAPI_MEMORY_FRAME_ALLOCATOR_HPP
+#define TEACHOS_KAPI_MEMORY_FRAME_ALLOCATOR_HPP
+
+#include "kapi/memory/frame.hpp"
+
+#include <optional>
+
+namespace teachos::memory
+{
+
+  struct frame_allocator
+  {
+    virtual auto allocate() -> std::optional<frame> = 0;
+    virtual auto release(frame frame) -> void = 0;
+  };
+
+}  // namespace teachos::memory
+
+#endif  // TEACHOS_KAPI_MEMORY_FRAME_ALLOCATOR_HPP
+\ No newline at end of file