ladybird/Kernel/Memory/RingBuffer.h
kleines Filmröllchen 4314c25cf2 Kernel: Require lock rank for Spinlock construction
All users which relied on the default constructor use a None lock rank
for now. This will make it easier to in the future remove LockRank and
actually annotate the ranks by searching for None.
2022-08-19 20:26:47 -07:00

42 lines
1.5 KiB
C++

/*
* Copyright (c) 2021, Sahan Fernando <sahan.h.fernando@gmail.com>.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <Kernel/PhysicalAddress.h>
#include <Kernel/UserOrKernelBuffer.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& 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:
RingBuffer(NonnullOwnPtr<Memory::Region> region, size_t capacity);
NonnullOwnPtr<Memory::Region> m_region;
Spinlock m_lock { LockRank::None };
size_t m_start_of_used {};
size_t m_num_used_bytes {};
size_t m_capacity_in_bytes {};
};
}