ladybird/Kernel/Memory/PageDirectory.h
Idan Horowitz bee2de4b31 Kernel: Use an IntrusiveRedBlackTree for storing the cr3 mappings
This ensures we don't allocate when intializing the PageDirectory.
2021-09-08 19:17:07 +03:00

72 lines
2.0 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/HashMap.h>
#include <AK/IntrusiveRedBlackTree.h>
#include <AK/RefCounted.h>
#include <AK/RefPtr.h>
#include <Kernel/Forward.h>
#include <Kernel/Memory/PhysicalPage.h>
#include <Kernel/Memory/VirtualRangeAllocator.h>
namespace Kernel::Memory {
class PageDirectory : public RefCounted<PageDirectory> {
friend class MemoryManager;
public:
static KResultOr<NonnullRefPtr<PageDirectory>> try_create_for_userspace(VirtualRangeAllocator const* parent_range_allocator = nullptr);
static NonnullRefPtr<PageDirectory> must_create_kernel_page_directory();
static RefPtr<PageDirectory> find_by_cr3(FlatPtr);
~PageDirectory();
void allocate_kernel_directory();
FlatPtr cr3() const
{
#if ARCH(X86_64)
return m_pml4t->paddr().get();
#else
return m_directory_table->paddr().get();
#endif
}
VirtualRangeAllocator& range_allocator() { return m_range_allocator; }
VirtualRangeAllocator const& range_allocator() const { return m_range_allocator; }
AddressSpace* address_space() { return m_space; }
const AddressSpace* address_space() const { return m_space; }
void set_space(Badge<AddressSpace>, AddressSpace& space) { m_space = &space; }
RecursiveSpinlock& get_lock() { return m_lock; }
// This has to be public to let the global singleton access the member pointer
IntrusiveRedBlackTreeNode<FlatPtr, PageDirectory, RawPtr<PageDirectory>> m_tree_node;
private:
PageDirectory();
AddressSpace* m_space { nullptr };
VirtualRangeAllocator m_range_allocator;
#if ARCH(X86_64)
RefPtr<PhysicalPage> m_pml4t;
#endif
RefPtr<PhysicalPage> m_directory_table;
#if ARCH(X86_64)
RefPtr<PhysicalPage> m_directory_pages[512];
#else
RefPtr<PhysicalPage> m_directory_pages[4];
#endif
HashMap<FlatPtr, NonnullRefPtr<PhysicalPage>> m_page_tables;
RecursiveSpinlock m_lock;
};
}