ladybird/Kernel/VM/PhysicalRegion.h
Brian Gianforcaro 1682f0b760 Everything: Move to SPDX license identifiers in all files.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.

See: https://spdx.dev/resources/use/#identifiers

This was done with the `ambr` search and replace tool.

 ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
2021-04-22 11:22:27 +02:00

55 lines
1.8 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Bitmap.h>
#include <AK/NonnullRefPtrVector.h>
#include <AK/Optional.h>
#include <AK/RefCounted.h>
#include <Kernel/VM/PhysicalPage.h>
namespace Kernel {
class PhysicalRegion : public RefCounted<PhysicalRegion> {
AK_MAKE_ETERNAL
public:
static NonnullRefPtr<PhysicalRegion> create(PhysicalAddress lower, PhysicalAddress upper);
~PhysicalRegion() = default;
void expand(PhysicalAddress lower, PhysicalAddress upper);
unsigned finalize_capacity();
PhysicalAddress lower() const { return m_lower; }
PhysicalAddress upper() const { return m_upper; }
unsigned size() const { return m_pages; }
unsigned used() const { return m_used - m_recently_returned.size(); }
unsigned free() const { return m_pages - m_used + m_recently_returned.size(); }
bool contains(const PhysicalPage& page) const { return page.paddr() >= m_lower && page.paddr() <= m_upper; }
RefPtr<PhysicalPage> take_free_page(bool supervisor);
NonnullRefPtrVector<PhysicalPage> take_contiguous_free_pages(size_t count, bool supervisor, size_t physical_alignment = PAGE_SIZE);
void return_page(const PhysicalPage& page);
private:
unsigned find_contiguous_free_pages(size_t count, size_t physical_alignment = PAGE_SIZE);
Optional<unsigned> find_and_allocate_contiguous_range(size_t count, unsigned alignment = 1);
Optional<unsigned> find_one_free_page();
void free_page_at(PhysicalAddress addr);
PhysicalRegion(PhysicalAddress lower, PhysicalAddress upper);
PhysicalAddress m_lower;
PhysicalAddress m_upper;
unsigned m_pages { 0 };
unsigned m_used { 0 };
Bitmap m_bitmap;
size_t m_free_hint { 0 };
Vector<PhysicalAddress, 256> m_recently_returned;
};
}