RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-31 17:58:12 +00:00
Code Issues Activity Actions

Kernel/Devices: Introduce the Device Control Device

Browse source 
This device will assist userspace to manage hotplug events.
A userspace application reads a DeviceEvent entry until the return value
is zero which indicates no events that are queued and waiting for
processing.
Trying to read with a buffer smaller than sizeof(DeviceEvent) results in
EOVERFLOW.
For now, there's no ioctl mechanism for this device but in the future an
acknowledgement mechanism can be implemented via ioctl(2) interface.
This commit is contained in:
Liav A 2021-12-20 11:10:35 +02:00 • committed by Linus Groh
parent b60e19fd34
commit b1ca39411b
7 changed files with 151 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

32
Kernel/Devices/DeviceControlDevice.h Normal file
View file

@ -0,0 +1,32 @@
/*
* Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <Kernel/Devices/CharacterDevice.h>
namespace Kernel {
class DeviceControlDevice final : public CharacterDevice {
friend class DeviceManagement;
public:
static NonnullRefPtr<DeviceControlDevice> must_create();
virtual ~DeviceControlDevice() override;
private:
DeviceControlDevice();
// ^CharacterDevice
virtual ErrorOr<void> ioctl(OpenFileDescription&, unsigned request, Userspace<void*> arg) override;
virtual ErrorOr<size_t> read(OpenFileDescription&, u64, UserOrKernelBuffer&, size_t) override;
virtual ErrorOr<size_t> write(OpenFileDescription&, u64, const UserOrKernelBuffer&, size_t) override { return Error::from_errno(ENOTSUP); }
virtual bool can_read(const OpenFileDescription&, size_t) const override;
virtual bool can_write(const OpenFileDescription&, size_t) const override { return false; }
virtual StringView class_name() const override { return "DeviceControlDevice"sv; }
};
}