jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2019-2020, Sergey Bugaev <bugaevc@serenityos.org>
3 * Copyright (c) 2022-2023, Liav A. <liavalb@hotmail.co.il>
4 *
5 * SPDX-License-Identifier: BSD-2-Clause
6 */
7
8#pragma once
9
10#include <Kernel/FileSystem/Inode.h>
11#include <Kernel/FileSystem/RAMFS/FileSystem.h>
12#include <Kernel/Forward.h>
13#include <Kernel/Memory/AnonymousVMObject.h>
14
15namespace Kernel {
16
17class RAMFSInode final : public Inode {
18 friend class RAMFS;
19
20public:
21 virtual ~RAMFSInode() override;
22
23 RAMFS& fs() { return static_cast<RAMFS&>(Inode::fs()); }
24 RAMFS const& fs() const { return static_cast<RAMFS const&>(Inode::fs()); }
25
26 // ^Inode
27 virtual InodeMetadata metadata() const override;
28 virtual ErrorOr<void> traverse_as_directory(Function<ErrorOr<void>(FileSystem::DirectoryEntryView const&)>) const override;
29 virtual ErrorOr<NonnullRefPtr<Inode>> lookup(StringView name) override;
30 virtual ErrorOr<void> flush_metadata() override;
31 virtual ErrorOr<NonnullRefPtr<Inode>> create_child(StringView name, mode_t, dev_t, UserID, GroupID) override;
32 virtual ErrorOr<void> add_child(Inode&, StringView name, mode_t) override;
33 virtual ErrorOr<void> remove_child(StringView name) override;
34 virtual ErrorOr<void> replace_child(StringView name, Inode& child) override;
35 virtual ErrorOr<void> chmod(mode_t) override;
36 virtual ErrorOr<void> chown(UserID, GroupID) override;
37 virtual ErrorOr<void> truncate(u64) override;
38 virtual ErrorOr<void> update_timestamps(Optional<Time> atime, Optional<Time> ctime, Optional<Time> mtime) override;
39
40private:
41 RAMFSInode(RAMFS& fs, InodeMetadata const& metadata, LockWeakPtr<RAMFSInode> parent);
42 explicit RAMFSInode(RAMFS& fs);
43 static ErrorOr<NonnullRefPtr<RAMFSInode>> try_create(RAMFS&, InodeMetadata const& metadata, LockWeakPtr<RAMFSInode> parent);
44 static ErrorOr<NonnullRefPtr<RAMFSInode>> try_create_root(RAMFS&);
45
46 // ^Inode
47 virtual ErrorOr<size_t> read_bytes_locked(off_t, size_t, UserOrKernelBuffer& buffer, OpenFileDescription*) const override;
48 virtual ErrorOr<size_t> write_bytes_locked(off_t, size_t, UserOrKernelBuffer const& buffer, OpenFileDescription*) override;
49
50 ErrorOr<size_t> do_io_on_content_space(Memory::Region& mapping_region, size_t offset, size_t io_size, UserOrKernelBuffer& buffer, bool write);
51
52 struct Child {
53 NonnullOwnPtr<KString> name;
54 NonnullRefPtr<RAMFSInode> inode;
55 IntrusiveListNode<Child> list_node {};
56 using List = IntrusiveList<&Child::list_node>;
57 };
58
59 Child* find_child_by_name(StringView);
60
61 InodeMetadata m_metadata;
62 LockWeakPtr<RAMFSInode> m_parent;
63
64 ErrorOr<void> ensure_allocated_blocks(size_t offset, size_t io_size);
65 ErrorOr<void> truncate_to_block_index(size_t block_index);
66 ErrorOr<size_t> read_bytes_from_content_space(size_t offset, size_t io_size, UserOrKernelBuffer& buffer) const;
67 ErrorOr<size_t> write_bytes_to_content_space(size_t offset, size_t io_size, UserOrKernelBuffer const& buffer);
68
69 struct DataBlock {
70 public:
71 using List = Vector<OwnPtr<DataBlock>>;
72
73 static ErrorOr<NonnullOwnPtr<DataBlock>> create();
74
75 constexpr static size_t block_size = 128 * KiB;
76
77 Memory::AnonymousVMObject& vmobject() { return *m_content_buffer_vmobject; }
78 Memory::AnonymousVMObject const& vmobject() const { return *m_content_buffer_vmobject; }
79
80 private:
81 explicit DataBlock(NonnullLockRefPtr<Memory::AnonymousVMObject> content_buffer_vmobject)
82 : m_content_buffer_vmobject(move(content_buffer_vmobject))
83 {
84 }
85
86 NonnullLockRefPtr<Memory::AnonymousVMObject> m_content_buffer_vmobject;
87 };
88
89 bool const m_root_directory_inode { false };
90
91 DataBlock::List m_blocks;
92 Child::List m_children;
93};
94
95}