ladybird/Kernel/VM/RingBuffer.h
x-yl 1fe08759e3 Kernel: Support multiport for VirtIOConsole
This involves refactoring VirtIOConsole into VirtIOConsole and
VirtIOConsolePort. VirtIOConsole is the VirtIODevice, it owns multiple
VirtIOConsolePorts as well as two control queues. Each
VirtIOConsolePort is a CharacterDevice.
2021-07-09 13:19:21 +04:30

41 lines
1.4 KiB
C++

/*
* Copyright (c) 2021, Sahan Fernando <sahan.h.fernando@gmail.com>.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/String.h>
#include <Kernel/PhysicalAddress.h>
#include <Kernel/UserOrKernelBuffer.h>
namespace Kernel {
class RingBuffer {
public:
RingBuffer(String region_name, size_t capacity);
bool has_space() const { return m_num_used_bytes < m_capacity_in_bytes; }
bool copy_data_in(const UserOrKernelBuffer& buffer, size_t offset, size_t length, PhysicalAddress& start_of_copied_data, size_t& bytes_copied);
KResultOr<size_t> copy_data_out(size_t size, UserOrKernelBuffer& buffer) const;
KResultOr<PhysicalAddress> reserve_space(size_t size);
void reclaim_space(PhysicalAddress chunk_start, size_t chunk_size);
PhysicalAddress start_of_used() const;
SpinLock<u8>& lock() { return m_lock; }
size_t used_bytes() const { return m_num_used_bytes; }
PhysicalAddress start_of_region() const { return m_region->physical_page(0)->paddr(); }
VirtualAddress vaddr() const { return m_region->vaddr(); }
size_t bytes_till_end() const { return (m_capacity_in_bytes - ((m_start_of_used + m_num_used_bytes) % m_capacity_in_bytes)) % m_capacity_in_bytes; };
private:
OwnPtr<Region> m_region;
SpinLock<u8> m_lock;
size_t m_start_of_used {};
size_t m_num_used_bytes {};
size_t m_capacity_in_bytes {};
};
}