ladybird/Kernel/VM/RangeAllocator.h
Andreas Kling 31e1af732f Kernel+LibC: Allow sys$mmap() callers to specify address alignment
This is exposed via the non-standard serenity_mmap() call in userspace.
2020-02-16 12:55:56 +01:00

112 lines
3.3 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/String.h>
#include <AK/Traits.h>
#include <AK/Vector.h>
#include <LibBareMetal/Memory/VirtualAddress.h>
namespace Kernel {
class Range {
friend class RangeAllocator;
public:
Range() {}
Range(VirtualAddress base, size_t size)
: m_base(base)
, m_size(size)
{
}
VirtualAddress base() const { return m_base; }
size_t size() const { return m_size; }
bool is_valid() const { return !m_base.is_null(); }
bool contains(VirtualAddress vaddr) const { return vaddr >= base() && vaddr < end(); }
VirtualAddress end() const { return m_base.offset(m_size); }
bool operator==(const Range& other) const
{
return m_base == other.m_base && m_size == other.m_size;
}
bool contains(VirtualAddress base, size_t size) const
{
if (base.offset(size) < base)
return false;
return base >= m_base && base.offset(size) <= end();
}
bool contains(const Range& other) const
{
return contains(other.base(), other.size());
}
Vector<Range, 2> carve(const Range&);
private:
VirtualAddress m_base;
size_t m_size { 0 };
};
class RangeAllocator {
public:
RangeAllocator();
~RangeAllocator();
void initialize_with_range(VirtualAddress, size_t);
void initialize_from_parent(const RangeAllocator&);
Range allocate_anywhere(size_t, size_t alignment = PAGE_SIZE);
Range allocate_specific(VirtualAddress, size_t);
void deallocate(Range);
void dump() const;
private:
void carve_at_index(int, const Range&);
Vector<Range> m_available_ranges;
Range m_total_range;
};
inline const LogStream& operator<<(const LogStream& stream, const Range& value)
{
return stream << String::format("Range(%x-%x)", value.base().get(), value.end().get() - 1);
}
}
namespace AK {
template<>
struct Traits<Kernel::Range> : public GenericTraits<Kernel::Range> {
static constexpr bool is_trivial() { return true; }
};
}