ladybird/Kernel/Devices/KCOVDevice.h
Andreas Kling ac7ce12123 Kernel: Remove the kmalloc_eternal heap :^)
This was a premature optimization from the early days of SerenityOS.
The eternal heap was a simple bump pointer allocator over a static
byte array. My original idea was to avoid heap fragmentation and improve
data locality, but both ideas were rooted in cargo culting, not data.

We would reserve 4 MiB at boot and only ended up using ~256 KiB, wasting
the rest.

This patch replaces all kmalloc_eternal() usage by regular kmalloc().
2021-12-28 21:02:38 +01:00

41 lines
1.5 KiB
C++

/*
* Copyright (c) 2021, Patrick Meyer <git@the-space.agency>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <Kernel/Devices/BlockDevice.h>
#include <Kernel/Devices/KCOVInstance.h>
namespace Kernel {
class KCOVDevice final : public BlockDevice {
friend class DeviceManagement;
public:
static HashMap<ProcessID, KCOVInstance*>* proc_instance;
static HashMap<ThreadID, KCOVInstance*>* thread_instance;
static NonnullRefPtr<KCOVDevice> must_create();
static void free_thread();
static void free_process();
// ^File
ErrorOr<Memory::Region*> mmap(Process&, OpenFileDescription&, Memory::VirtualRange const&, u64 offset, int prot, bool shared) override;
ErrorOr<NonnullRefPtr<OpenFileDescription>> open(int options) override;
protected:
KCOVDevice();
virtual StringView class_name() const override { return "KCOVDevice"sv; }
virtual bool can_read(const OpenFileDescription&, size_t) const override final { return true; }
virtual bool can_write(const OpenFileDescription&, size_t) const override final { return true; }
virtual void start_request(AsyncBlockDeviceRequest& request) override final { request.complete(AsyncDeviceRequest::Failure); }
virtual ErrorOr<size_t> read(OpenFileDescription&, u64, UserOrKernelBuffer&, size_t) override { return EINVAL; }
virtual ErrorOr<size_t> write(OpenFileDescription&, u64, const UserOrKernelBuffer&, size_t) override { return EINVAL; }
virtual ErrorOr<void> ioctl(OpenFileDescription&, unsigned request, Userspace<void*> arg) override;
};
}