ladybird/Kernel/Memory/VirtualRange.cpp
Andreas Kling 79fa9765ca Kernel: Replace KResult and KResultOr<T> with Error and ErrorOr<T>
We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace!
This was a slightly tedious refactoring that took a long time, so it's
not unlikely that some bugs crept in.

Nevertheless, it does pass basic functionality testing, and it's just
real nice to finally see the same pattern in all contexts. :^)
2021-11-08 01:10:53 +01:00

56 lines
1.5 KiB
C++

/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2021, Leon Albrecht <leon2002.la@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Vector.h>
#include <Kernel/Memory/MemoryManager.h>
#include <Kernel/Memory/VirtualRange.h>
#include <LibC/limits.h>
namespace Kernel::Memory {
Vector<VirtualRange, 2> VirtualRange::carve(VirtualRange const& taken) const
{
VERIFY((taken.size() % PAGE_SIZE) == 0);
Vector<VirtualRange, 2> parts;
if (taken == *this)
return {};
if (taken.base() > base())
parts.append({ base(), taken.base().get() - base().get() });
if (taken.end() < end())
parts.append({ taken.end(), end().get() - taken.end().get() });
return parts;
}
VirtualRange VirtualRange::intersect(VirtualRange const& other) const
{
if (*this == other) {
return *this;
}
auto new_base = max(base(), other.base());
auto new_end = min(end(), other.end());
VERIFY(new_base < new_end);
return VirtualRange(new_base, (new_end - new_base).get());
}
ErrorOr<VirtualRange> VirtualRange::expand_to_page_boundaries(FlatPtr address, size_t size)
{
if (page_round_up_would_wrap(size))
return EINVAL;
if ((address + size) < address)
return EINVAL;
if (page_round_up_would_wrap(address + size))
return EINVAL;
auto base = VirtualAddress { address }.page_base();
auto end = page_round_up(address + size);
return VirtualRange { base, end - base.get() };
}
}