Atmosphere/libraries/libmesosphere/source/kern_k_memory_manager.cpp
2020-01-29 01:49:04 -08:00

35 lines
1.4 KiB
C++

/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <mesosphere.hpp>
namespace ams::kern {
namespace {
constexpr size_t g_memory_block_page_shifts[] = { 0xC, 0x10, 0x15, 0x16, 0x19, 0x1D, 0x1E };
constexpr size_t NumMemoryBlockPageShifts = util::size(g_memory_block_page_shifts);
}
size_t KMemoryManager::Impl::CalculateMetadataOverheadSize(size_t region_size) {
const size_t ref_count_size = (region_size / PageSize) * sizeof(u16);
const size_t bitmap_size = (util::AlignUp((region_size / PageSize), BITSIZEOF(u64)) / BITSIZEOF(u64)) * sizeof(u64);
const size_t page_heap_size = KPageHeap::CalculateMetadataOverheadSize(region_size, g_memory_block_page_shifts, NumMemoryBlockPageShifts);
return util::AlignUp(page_heap_size + bitmap_size + ref_count_size, PageSize);
}
}