Kernel: Split the TmpFS core files into smaller components

Author: https://github.com/supercomputer7
Commit: https://github.com/SerenityOS/serenity/commit/5e6101dd3e
Pull-request: https://github.com/SerenityOS/serenity/pull/15771
Reviewed-by: https://github.com/ADKaster ✅
Reviewed-by: https://github.com/bgianfo

Kernel/CMakeLists.txt

@@ -183,7 +183,8 @@ set(KERNEL_SOURCES
     FileSystem/SysFS/Subsystems/Kernel/Variables/Directory.cpp
     FileSystem/SysFS/Subsystems/Kernel/Variables/DumpKmallocStack.cpp
     FileSystem/SysFS/Subsystems/Kernel/Variables/UBSANDeadly.cpp
-    FileSystem/TmpFS.cpp
+    FileSystem/TmpFS/FileSystem.cpp
+    FileSystem/TmpFS/Inode.cpp
     FileSystem/VirtualFileSystem.cpp
     Firmware/BIOS.cpp
     Firmware/ACPI/Initialize.cpp

Kernel/FileSystem/TmpFS/FileSystem.cpp

@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
+ * Copyright (c) 2022, Liav A. <liavalb@hotmail.co.il>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <Kernel/FileSystem/TmpFS/FileSystem.h>
+#include <Kernel/FileSystem/TmpFS/Inode.h>
+
+namespace Kernel {
+
+ErrorOr<NonnullLockRefPtr<FileSystem>> TmpFS::try_create()
+{
+    return TRY(adopt_nonnull_lock_ref_or_enomem(new (nothrow) TmpFS));
+}
+
+TmpFS::TmpFS() = default;
+TmpFS::~TmpFS() = default;
+
+ErrorOr<void> TmpFS::initialize()
+{
+    m_root_inode = TRY(TmpFSInode::try_create_root(*this));
+    return {};
+}
+
+Inode& TmpFS::root_inode()
+{
+    VERIFY(!m_root_inode.is_null());
+    return *m_root_inode;
+}
+
+unsigned TmpFS::next_inode_index()
+{
+    MutexLocker locker(m_lock);
+
+    return m_next_inode_index++;
+}
+
+}

Kernel/FileSystem/TmpFS/FileSystem.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
+ * Copyright (c) 2022, Liav A. <liavalb@hotmail.co.il>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <Kernel/FileSystem/FileSystem.h>
+#include <Kernel/FileSystem/Inode.h>
+#include <Kernel/Forward.h>
+
+namespace Kernel {
+
+class TmpFS final : public FileSystem {
+    friend class TmpFSInode;
+
+public:
+    virtual ~TmpFS() override;
+    static ErrorOr<NonnullLockRefPtr<FileSystem>> try_create();
+    virtual ErrorOr<void> initialize() override;
+
+    virtual StringView class_name() const override { return "TmpFS"sv; }
+
+    virtual bool supports_watchers() const override { return true; }
+
+    virtual Inode& root_inode() override;
+
+private:
+    TmpFS();
+
+    LockRefPtr<TmpFSInode> m_root_inode;
+
+    unsigned m_next_inode_index { 1 };
+    unsigned next_inode_index();
+};
+
+}

Kernel/FileSystem/TmpFS/Inode.cpp

@@ -5,39 +5,11 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
-#include <Kernel/FileSystem/TmpFS.h>
+#include <Kernel/FileSystem/TmpFS/Inode.h>
 #include <Kernel/Process.h>
-#include <LibC/limits.h>
 
 namespace Kernel {
 
-ErrorOr<NonnullLockRefPtr<FileSystem>> TmpFS::try_create()
-{
-    return TRY(adopt_nonnull_lock_ref_or_enomem(new (nothrow) TmpFS));
-}
-
-TmpFS::TmpFS() = default;
-TmpFS::~TmpFS() = default;
-
-ErrorOr<void> TmpFS::initialize()
-{
-    m_root_inode = TRY(TmpFSInode::try_create_root(*this));
-    return {};
-}
-
-Inode& TmpFS::root_inode()
-{
-    VERIFY(!m_root_inode.is_null());
-    return *m_root_inode;
-}
-
-unsigned TmpFS::next_inode_index()
-{
-    MutexLocker locker(m_lock);
-
-    return m_next_inode_index++;
-}
-
 TmpFSInode::TmpFSInode(TmpFS& fs, InodeMetadata const& metadata, LockWeakPtr<TmpFSInode> parent)
     : Inode(fs, fs.next_inode_index())
     , m_metadata(metadata)

Kernel/FileSystem/TmpFS/Inode.h

@@ -7,39 +7,12 @@
 
 #pragma once
 
-#include <Kernel/FileSystem/FileSystem.h>
 #include <Kernel/FileSystem/Inode.h>
-#include <Kernel/KBuffer.h>
-#include <Kernel/Locking/MutexProtected.h>
+#include <Kernel/FileSystem/TmpFS/FileSystem.h>
 #include <Kernel/Memory/AnonymousVMObject.h>
 
 namespace Kernel {
 
-class TmpFSInode;
-
-class TmpFS final : public FileSystem {
-    friend class TmpFSInode;
-
-public:
-    virtual ~TmpFS() override;
-    static ErrorOr<NonnullLockRefPtr<FileSystem>> try_create();
-    virtual ErrorOr<void> initialize() override;
-
-    virtual StringView class_name() const override { return "TmpFS"sv; }
-
-    virtual bool supports_watchers() const override { return true; }
-
-    virtual Inode& root_inode() override;
-
-private:
-    TmpFS();
-
-    LockRefPtr<TmpFSInode> m_root_inode;
-
-    unsigned m_next_inode_index { 1 };
-    unsigned next_inode_index();
-};
-
 class TmpFSInode final : public Inode {
     friend class TmpFS;
 

Kernel/Forward.h

@@ -61,6 +61,7 @@ class TCPSocket;
 class TTY;
 class Thread;
 class ThreadTracer;
+class TmpFSInode;
 class UDPSocket;
 class UserOrKernelBuffer;
 class VirtualFileSystem;

Kernel/Syscalls/mount.cpp

@@ -12,7 +12,7 @@
 #include <Kernel/FileSystem/Plan9FileSystem.h>
 #include <Kernel/FileSystem/ProcFS.h>
 #include <Kernel/FileSystem/SysFS/FileSystem.h>
-#include <Kernel/FileSystem/TmpFS.h>
+#include <Kernel/FileSystem/TmpFS/FileSystem.h>
 #include <Kernel/FileSystem/VirtualFileSystem.h>
 #include <Kernel/Process.h>