jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#pragma once
8
9#include <Kernel/FileSystem/FileBackedFileSystem.h>
10#include <Kernel/Locking/MutexProtected.h>
11
12namespace Kernel {
13
14class BlockBasedFileSystem : public FileBackedFileSystem {
15public:
16 AK_TYPEDEF_DISTINCT_ORDERED_ID(u64, BlockIndex);
17
18 virtual ~BlockBasedFileSystem() override;
19
20 u64 logical_block_size() const { return m_logical_block_size; };
21
22 virtual void flush_writes() override;
23 void flush_writes_impl();
24
25protected:
26 explicit BlockBasedFileSystem(OpenFileDescription&);
27
28 virtual ErrorOr<void> initialize_while_locked() override;
29
30 ErrorOr<void> read_block(BlockIndex, UserOrKernelBuffer*, size_t count, u64 offset = 0, bool allow_cache = true) const;
31 ErrorOr<void> read_blocks(BlockIndex, unsigned count, UserOrKernelBuffer&, bool allow_cache = true) const;
32
33 ErrorOr<void> raw_read(BlockIndex, UserOrKernelBuffer&);
34 ErrorOr<void> raw_write(BlockIndex, UserOrKernelBuffer const&);
35
36 ErrorOr<void> raw_read_blocks(BlockIndex index, size_t count, UserOrKernelBuffer&);
37 ErrorOr<void> raw_write_blocks(BlockIndex index, size_t count, UserOrKernelBuffer const&);
38
39 ErrorOr<void> write_block(BlockIndex, UserOrKernelBuffer const&, size_t count, u64 offset = 0, bool allow_cache = true);
40 ErrorOr<void> write_blocks(BlockIndex, unsigned count, UserOrKernelBuffer const&, bool allow_cache = true);
41
42 u64 m_logical_block_size { 512 };
43
44 void remove_disk_cache_before_last_unmount();
45
46private:
47 void flush_specific_block_if_needed(BlockIndex index);
48
49 mutable MutexProtected<OwnPtr<DiskCache>> m_cache;
50};
51
52}