serenity/Kernel/FileSystem/FileSystem.h
2022-04-01 21:24:45 +01:00

101 lines
2.7 KiB
C++

/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Error.h>
#include <AK/RefCounted.h>
#include <AK/RefPtr.h>
#include <AK/StringView.h>
#include <Kernel/FileSystem/InodeIdentifier.h>
#include <Kernel/Forward.h>
#include <Kernel/Locking/Mutex.h>
#include <Kernel/UnixTypes.h>
#include <Kernel/UserOrKernelBuffer.h>
namespace Kernel {
static constexpr u32 mepoch = 476763780;
class FileSystem : public RefCounted<FileSystem> {
friend class Inode;
public:
virtual ~FileSystem();
FileSystemID fsid() const { return m_fsid; }
static FileSystem* from_fsid(FileSystemID);
static void sync();
static void lock_all();
virtual ErrorOr<void> initialize() = 0;
virtual StringView class_name() const = 0;
virtual Inode& root_inode() = 0;
virtual bool supports_watchers() const { return false; }
bool is_readonly() const { return m_readonly; }
virtual unsigned total_block_count() const { return 0; }
virtual unsigned free_block_count() const { return 0; }
virtual unsigned total_inode_count() const { return 0; }
virtual unsigned free_inode_count() const { return 0; }
virtual ErrorOr<void> prepare_to_unmount() { return {}; }
struct DirectoryEntryView {
DirectoryEntryView(StringView name, InodeIdentifier, u8 file_type);
StringView name;
InodeIdentifier inode;
u8 file_type { 0 };
};
virtual void flush_writes() { }
u64 block_size() const { return m_block_size; }
size_t fragment_size() const { return m_fragment_size; }
virtual bool is_file_backed() const { return false; }
// Converts file types that are used internally by the filesystem to DT_* types
virtual u8 internal_file_type_to_directory_entry_type(DirectoryEntryView const& entry) const { return entry.file_type; }
protected:
FileSystem();
void set_block_size(u64 size) { m_block_size = size; }
void set_fragment_size(size_t size) { m_fragment_size = size; }
mutable Mutex m_lock { "FS" };
private:
FileSystemID m_fsid;
u64 m_block_size { 0 };
size_t m_fragment_size { 0 };
bool m_readonly { false };
};
inline FileSystem* InodeIdentifier::fs() // NOLINT(readability-make-member-function-const) const InodeIdentifiers should not be able to modify the FileSystem
{
return FileSystem::from_fsid(m_fsid);
}
inline FileSystem const* InodeIdentifier::fs() const
{
return FileSystem::from_fsid(m_fsid);
}
}
namespace AK {
template<>
struct Traits<Kernel::InodeIdentifier> : public GenericTraits<Kernel::InodeIdentifier> {
static unsigned hash(Kernel::InodeIdentifier const& inode) { return pair_int_hash(inode.fsid().value(), inode.index().value()); }
};
}