Merge branch 'improve-mount-reference-count' into 'develop-BA-FS26'

Increase reference count of source_mount when one of its files is mounted somewhere

See merge request teachos/kernel!42

1 files changed, 10 insertions, 4 deletions

diff --git a/kernel/src/filesystem/mount.cpp b/kernel/src/filesystem/mount.cpp
index b64c370..ead7479 100644
--- a/kernel/src/filesystem/mount.cpp
+++ b/kernel/src/filesystem/mount.cpp
@@ -14,11 +14,13 @@
 namespace kernel::filesystem
 {
   mount::mount(kstd::shared_ptr<dentry> const & mount_dentry, kstd::shared_ptr<dentry> const & root_dentry,
-               kstd::shared_ptr<filesystem> const & fs, kstd::shared_ptr<mount> const & parent_mount)
+               kstd::shared_ptr<filesystem> const & fs, kstd::shared_ptr<mount> const & parent_mount,
+               kstd::shared_ptr<mount> const & source_mount)
       : m_mount_dentry(mount_dentry)
       , m_root_dentry(root_dentry)
       , m_filesystem(fs)
       , m_parent_mount(parent_mount)
+      , m_source_mount(source_mount)
       , m_ref_count(0)
   {
     if (!m_filesystem)
@@ -56,20 +58,24 @@ namespace kernel::filesystem
     return m_parent_mount;
   }
 
+  auto mount::source_mount() const -> kstd::shared_ptr<mount>
+  {
+    return m_source_mount.lock();
+  }
+
   auto mount::increment_ref_count() -> void
   {
     m_ref_count += 1;
   }
 
-  auto mount::decrement_ref_count() -> bool
+  auto mount::decrement_ref_count() -> void
   {
     if (m_ref_count == 0)
     {
-      return false;
+      kapi::system::panic("[FILESYSTEM] decrement_ref_count() was called but ref_count is 0");
     }
 
     m_ref_count -= 1;
-    return true;
   }
 
   auto mount::is_ready_to_unmount() const -> bool