banan-os/kernel/include/kernel/FS/Ext2/FileSystem.h

129 lines
3.1 KiB
C++

#pragma once
#include <BAN/HashMap.h>
#include <kernel/Device/Device.h>
#include <kernel/FS/FileSystem.h>
#include <kernel/FS/Ext2/Inode.h>
namespace Kernel
{
class Ext2FS final : public FileSystem
{
public:
class BlockBufferWrapper
{
BAN_NON_COPYABLE(BlockBufferWrapper);
BAN_NON_MOVABLE(BlockBufferWrapper);
public:
BlockBufferWrapper(BAN::Span<uint8_t> buffer, bool& used)
: m_buffer(buffer)
, m_used(used)
{
ASSERT(m_used);
}
~BlockBufferWrapper()
{
m_used = false;
}
size_t size() const { return m_buffer.size(); }
uint8_t* data() { return m_buffer.data(); }
const uint8_t* data() const { return m_buffer.data(); }
BAN::ByteSpan span() { return m_buffer; }
BAN::ConstByteSpan span() const { return m_buffer.as_const(); }
uint8_t& operator[](size_t index) { return m_buffer[index]; }
uint8_t operator[](size_t index) const { return m_buffer[index]; }
private:
BAN::Span<uint8_t> m_buffer;
bool& m_used;
};
public:
static BAN::ErrorOr<bool> probe(BAN::RefPtr<BlockDevice>);
static BAN::ErrorOr<BAN::RefPtr<Ext2FS>> create(BAN::RefPtr<BlockDevice>);
virtual BAN::RefPtr<Inode> root_inode() override { return m_root_inode; }
virtual dev_t dev() const override { return m_block_device->rdev(); };
private:
Ext2FS(BAN::RefPtr<BlockDevice> block_device)
: m_block_device(block_device)
{}
BAN::ErrorOr<void> initialize_superblock();
BAN::ErrorOr<void> initialize_root_inode();
BAN::ErrorOr<uint32_t> create_inode(const Ext2::Inode&);
BAN::ErrorOr<void> delete_inode(uint32_t ino);
BAN::ErrorOr<void> resize_inode(uint32_t, size_t);
BAN::ErrorOr<void> read_block(uint32_t, BlockBufferWrapper&);
BAN::ErrorOr<void> write_block(uint32_t, const BlockBufferWrapper&);
BAN::ErrorOr<void> sync_superblock();
BAN::ErrorOr<void> sync_block(uint32_t block);
BlockBufferWrapper get_block_buffer();
BAN::ErrorOr<uint32_t> reserve_free_block(uint32_t primary_bgd);
BAN::ErrorOr<void> release_block(uint32_t block);
BAN::HashMap<ino_t, BAN::RefPtr<Ext2Inode>>& inode_cache() { return m_inode_cache; }
const Ext2::Superblock& superblock() const { return m_superblock; }
struct BlockLocation
{
uint32_t block;
uint32_t offset;
};
BAN::ErrorOr<BlockLocation> locate_inode(uint32_t);
BlockLocation locate_block_group_descriptior(uint32_t);
uint32_t block_size() const { return 1024 << superblock().log_block_size; }
class BlockBufferManager
{
public:
BlockBufferManager() = default;
BlockBufferWrapper get_buffer();
BAN::ErrorOr<void> initialize(size_t block_size);
private:
struct BlockBuffer
{
BAN::Vector<uint8_t> buffer;
bool used { false };
};
private:
BAN::Array<BlockBuffer, 10> m_buffers;
};
private:
Mutex m_mutex;
BAN::RefPtr<BlockDevice> m_block_device;
BAN::RefPtr<Inode> m_root_inode;
BAN::Vector<uint32_t> m_superblock_backups;
BAN::HashMap<ino_t, BAN::RefPtr<Ext2Inode>> m_inode_cache;
BlockBufferManager m_buffer_manager;
Ext2::Superblock m_superblock;
friend class Ext2Inode;
friend class BAN::RefPtr<Ext2FS>;
};
}