ladybird/Kernel/VM/PageDirectory.h

79 lines
2.9 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/HashMap.h>
#include <AK/RefCounted.h>
#include <AK/RefPtr.h>
#include <Kernel/VM/PhysicalPage.h>
#include <Kernel/VM/RangeAllocator.h>
namespace Kernel {
class Process;
class PageDirectory : public RefCounted<PageDirectory> {
friend class MemoryManager;
public:
static RefPtr<PageDirectory> create_for_userspace(Process& process, const RangeAllocator* parent_range_allocator = nullptr)
{
auto page_directory = adopt(*new PageDirectory(process, parent_range_allocator));
if (!page_directory->process())
return {};
return page_directory;
}
static NonnullRefPtr<PageDirectory> create_kernel_page_directory() { return adopt(*new PageDirectory); }
static RefPtr<PageDirectory> find_by_cr3(u32);
~PageDirectory();
u32 cr3() const { return m_directory_table->paddr().get(); }
RangeAllocator& range_allocator() { return m_range_allocator; }
RangeAllocator& identity_range_allocator() { return m_identity_range_allocator; }
Process* process() { return m_process; }
const Process* process() const { return m_process; }
RecursiveSpinLock& get_lock() { return m_lock; }
private:
PageDirectory(Process&, const RangeAllocator* parent_range_allocator);
PageDirectory();
Process* m_process { nullptr };
RangeAllocator m_range_allocator;
RangeAllocator m_identity_range_allocator;
RefPtr<PhysicalPage> m_directory_table;
RefPtr<PhysicalPage> m_directory_pages[4];
HashMap<u32, RefPtr<PhysicalPage>> m_page_tables;
RecursiveSpinLock m_lock;
};
}