ladybird/Kernel/Memory/RingBuffer.h
Kirill Nikolaev 6cdb1f0415 Kernel: Add an initial implementation of virtio-net driver
It can be exercised by setting
    SERENITY_ETHERNET_DEVICE_TYPE=virtio-net-pci.
2023-07-11 00:49:11 -06:00

43 lines
1.6 KiB
C++

/*
* Copyright (c) 2021, Sahan Fernando <sahan.h.fernando@gmail.com>.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <Kernel/Library/UserOrKernelBuffer.h>
#include <Kernel/Memory/PhysicalAddress.h>
namespace Kernel::Memory {
class RingBuffer {
public:
static ErrorOr<NonnullOwnPtr<RingBuffer>> try_create(StringView region_name, size_t capacity);
bool has_space() const { return m_num_used_bytes < m_capacity_in_bytes; }
bool copy_data_in(UserOrKernelBuffer const& buffer, size_t offset, size_t length, PhysicalAddress& start_of_copied_data, size_t& bytes_copied);
ErrorOr<size_t> copy_data_out(size_t size, UserOrKernelBuffer& buffer) const;
ErrorOr<PhysicalAddress> reserve_space(size_t size);
void reclaim_space(PhysicalAddress chunk_start, size_t chunk_size);
PhysicalAddress start_of_used() const;
Spinlock<LockRank::None>& lock() { return m_lock; }
size_t used_bytes() const { return m_num_used_bytes; }
size_t available_bytes() const { return m_capacity_in_bytes - 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:
RingBuffer(NonnullOwnPtr<Memory::Region> region, size_t capacity);
NonnullOwnPtr<Memory::Region> m_region;
Spinlock<LockRank::None> m_lock {};
size_t m_start_of_used {};
size_t m_num_used_bytes {};
size_t m_capacity_in_bytes {};
};
}