Files
serenity/Kernel/Devices/Loop/LoopDevice.h
Liav A. 96e1391c23 Kernel/Devices: Remove the DeviceManagement singleton
This change has many improvements:
- We don't use `LockRefPtr` to hold instances of many base devices as
  with the DeviceManagement class. Instead, we have a saner pattern of
  holding them in a `NonnullRefPtr<T> const`, in a small-text footprint
  class definition in the `Device.cpp` file.
- The awkwardness of using `::the()` each time we need to get references
  to mostly-static objects (like the Event queue) in runtime is now gone
  in the migration to using the `Device` class.
- Acquiring a device feel more obvious because we use now the Device
  class for this method. The method name is improved as well.
2024-10-05 12:26:48 +02:00

63 lines
2.0 KiB
C++

/*
* Copyright (c) 2024, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Badge.h>
#include <AK/IntrusiveList.h>
#include <Kernel/Devices/BlockDevice.h>
#include <Kernel/FileSystem/Inode.h>
#include <Kernel/Forward.h>
#include <Kernel/Library/ListedRefCounted.h>
namespace Kernel {
class LoopDevice final : public BlockDevice {
friend class Device;
public:
virtual bool unref() const override;
virtual ~LoopDevice() = default;
void remove(Badge<DeviceControlDevice>);
static ErrorOr<NonnullRefPtr<LoopDevice>> create_with_file_description(OpenFileDescription&);
virtual StringView class_name() const override { return "LoopDevice"sv; }
virtual ErrorOr<size_t> read(OpenFileDescription&, u64, UserOrKernelBuffer&, size_t) override;
virtual ErrorOr<size_t> write(OpenFileDescription&, u64, UserOrKernelBuffer const&, size_t) override;
virtual bool can_read(OpenFileDescription const&, u64) const override;
virtual bool can_write(OpenFileDescription const&, u64) const override;
virtual ErrorOr<void> ioctl(OpenFileDescription&, unsigned request, Userspace<void*> arg) override;
virtual bool is_loop_device() const override { return true; }
unsigned index() const { return m_index; }
Inode const& inode() const { return m_backing_custody->inode(); }
Inode& inode() { return m_backing_custody->inode(); }
Custody const& custody() const { return *m_backing_custody; }
Custody& custody() { return *m_backing_custody; }
private:
virtual void start_request(AsyncBlockDeviceRequest&) override;
LoopDevice(NonnullRefPtr<Custody>, unsigned index);
NonnullRefPtr<Custody> const m_backing_custody;
unsigned const m_index { 0 };
mutable IntrusiveListNode<LoopDevice, NonnullRefPtr<LoopDevice>> m_list_node;
public:
using List = IntrusiveList<&LoopDevice::m_list_node>;
static SpinlockProtected<LoopDevice::List, LockRank::None>& all_instances();
};
}