Add missing comments

1 files changed, 12 insertions, 18 deletions

diff --git a/arch/x86_64/src/memory/heap/linked_list_allocator.cpp b/arch/x86_64/src/memory/heap/linked_list_allocator.cpp
index d922dc8..6600c6e 100644
--- a/arch/x86_64/src/memory/heap/linked_list_allocator.cpp
+++ b/arch/x86_64/src/memory/heap/linked_list_allocator.cpp
@@ -36,7 +36,7 @@ namespace teachos::arch::memory::heap
     {
       if (current->size == size)
       {
-        return remove_free_memory_block(previous, current, size);
+        return remove_free_memory_block(previous, current);
       }
       else if (current->size >= size + min_allocatable_size())
       {
@@ -81,31 +81,25 @@ namespace teachos::arch::memory::heap
     mutex.unlock();
   }
 
-  auto linked_list_allocator::remove_free_memory_block(memory_block * previous_block, memory_block * current_block,
-                                                       std::size_t size) -> void *
+  auto linked_list_allocator::remove_free_memory_block(memory_block * previous_block,
+                                                       memory_block * current_block) -> void *
   {
-    auto const start_address = reinterpret_cast<std::size_t>(current_block);
-    // If we want to allocate into the first block that is before any other free block, then there exists no previous
-    // free block (nullptr). Therefore we have to overwrite the first block instead of overwriting its next value.
-    if (previous_block == nullptr)
-    {
-      first = nullptr;
-    }
-    else
-    {
-      previous_block->next = current_block->next;
-    }
-    clear_memory_block_header(current_block);
-    return reinterpret_cast<void *>(start_address);
+    return replace_free_memory_block(previous_block, current_block, current_block->next);
   }
 
   auto linked_list_allocator::split_free_memory_block(memory_block * previous_block, memory_block * current_block,
                                                       std::size_t size) -> void *
   {
-    auto const start_address = reinterpret_cast<std::size_t>(current_block);
-    auto const end_address = start_address + size;
+    auto const end_address = reinterpret_cast<std::size_t>(current_block) + size;
     auto const new_block =
         new (reinterpret_cast<void *>(end_address)) memory_block(current_block->size - size, current_block->next);
+    return replace_free_memory_block(previous_block, current_block, new_block);
+  }
+
+  auto linked_list_allocator::replace_free_memory_block(memory_block * previous_block, memory_block * current_block,
+                                                        memory_block * new_block) -> void *
+  {
+    auto const start_address = reinterpret_cast<std::size_t>(current_block);
     // If we want to allocate into the first block that is before any other free block, then there exists no previous
     // free block (nullptr). Therefore we have to overwrite the first block instead of overwriting its next value.
     if (previous_block == nullptr)