1 files changed, 43 insertions, 0 deletions
diff --git a/Kernel/Memory/PhysicalPage.cpp b/Kernel/Memory/PhysicalPage.cpp
new file mode 100644
index 0000000000..fda876dc0d
--- /dev/null
+++ b/Kernel/Memory/PhysicalPage.cpp
@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <Kernel/Heap/kmalloc.h>
+#include <Kernel/Memory/MemoryManager.h>
+#include <Kernel/Memory/PhysicalPage.h>
+
+namespace Kernel {
+
+NonnullRefPtr<PhysicalPage> PhysicalPage::create(PhysicalAddress paddr, MayReturnToFreeList may_return_to_freelist)
+{
+    auto& physical_page_entry = MM.get_physical_page_entry(paddr);
+    return adopt_ref(*new (&physical_page_entry.allocated.physical_page) PhysicalPage(may_return_to_freelist));
+}
+
+PhysicalPage::PhysicalPage(MayReturnToFreeList may_return_to_freelist)
+    : m_may_return_to_freelist(may_return_to_freelist)
+{
+}
+
+PhysicalAddress PhysicalPage::paddr() const
+{
+    return MM.get_physical_address(*this);
+}
+
+void PhysicalPage::free_this()
+{
+    auto paddr = MM.get_physical_address(*this);
+    if (m_may_return_to_freelist == MayReturnToFreeList::Yes) {
+        auto& this_as_freelist_entry = MM.get_physical_page_entry(paddr).freelist;
+        this->~PhysicalPage(); // delete in place
+        this_as_freelist_entry.next_index = -1;
+        this_as_freelist_entry.prev_index = -1;
+        MM.deallocate_physical_page(paddr);
+    } else {
+        this->~PhysicalPage(); // delete in place
+    }
+}
+
+}