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Diffstat (limited to 'src/core/hle/kernel/k_page_heap.h')
-rw-r--r-- | src/core/hle/kernel/k_page_heap.h | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/src/core/hle/kernel/k_page_heap.h b/src/core/hle/kernel/k_page_heap.h new file mode 100644 index 000000000..de5d6a189 --- /dev/null +++ b/src/core/hle/kernel/k_page_heap.h @@ -0,0 +1,193 @@ +// Copyright 2020 yuzu Emulator Project +// Licensed under GPLv2 or any later version +// Refer to the license.txt file included. + +#pragma once + +#include <array> +#include <bit> +#include <vector> + +#include "common/alignment.h" +#include "common/assert.h" +#include "common/common_funcs.h" +#include "common/common_types.h" +#include "core/hle/kernel/k_page_bitmap.h" +#include "core/hle/kernel/memory_types.h" + +namespace Kernel { + +class KPageHeap final : NonCopyable { +public: + static constexpr s32 GetAlignedBlockIndex(std::size_t num_pages, std::size_t align_pages) { + const auto target_pages{std::max(num_pages, align_pages)}; + for (std::size_t i = 0; i < NumMemoryBlockPageShifts; i++) { + if (target_pages <= + (static_cast<std::size_t>(1) << MemoryBlockPageShifts[i]) / PageSize) { + return static_cast<s32>(i); + } + } + return -1; + } + + static constexpr s32 GetBlockIndex(std::size_t num_pages) { + for (s32 i{static_cast<s32>(NumMemoryBlockPageShifts) - 1}; i >= 0; i--) { + if (num_pages >= (static_cast<std::size_t>(1) << MemoryBlockPageShifts[i]) / PageSize) { + return i; + } + } + return -1; + } + + static constexpr std::size_t GetBlockSize(std::size_t index) { + return static_cast<std::size_t>(1) << MemoryBlockPageShifts[index]; + } + + static constexpr std::size_t GetBlockNumPages(std::size_t index) { + return GetBlockSize(index) / PageSize; + } + +private: + static constexpr std::size_t NumMemoryBlockPageShifts{7}; + static constexpr std::array<std::size_t, NumMemoryBlockPageShifts> MemoryBlockPageShifts{ + 0xC, 0x10, 0x15, 0x16, 0x19, 0x1D, 0x1E, + }; + + class Block final : NonCopyable { + private: + KPageBitmap bitmap; + VAddr heap_address{}; + uintptr_t end_offset{}; + std::size_t block_shift{}; + std::size_t next_block_shift{}; + + public: + Block() = default; + + constexpr std::size_t GetShift() const { + return block_shift; + } + constexpr std::size_t GetNextShift() const { + return next_block_shift; + } + constexpr std::size_t GetSize() const { + return static_cast<std::size_t>(1) << GetShift(); + } + constexpr std::size_t GetNumPages() const { + return GetSize() / PageSize; + } + constexpr std::size_t GetNumFreeBlocks() const { + return bitmap.GetNumBits(); + } + constexpr std::size_t GetNumFreePages() const { + return GetNumFreeBlocks() * GetNumPages(); + } + + u64* Initialize(VAddr addr, std::size_t size, std::size_t bs, std::size_t nbs, + u64* bit_storage) { + // Set shifts + block_shift = bs; + next_block_shift = nbs; + + // Align up the address + VAddr end{addr + size}; + const auto align{(next_block_shift != 0) ? (1ULL << next_block_shift) + : (1ULL << block_shift)}; + addr = Common::AlignDown((addr), align); + end = Common::AlignUp((end), align); + + heap_address = addr; + end_offset = (end - addr) / (1ULL << block_shift); + return bitmap.Initialize(bit_storage, end_offset); + } + + VAddr PushBlock(VAddr address) { + // Set the bit for the free block + std::size_t offset{(address - heap_address) >> GetShift()}; + bitmap.SetBit(offset); + + // If we have a next shift, try to clear the blocks below and return the address + if (GetNextShift()) { + const auto diff{1ULL << (GetNextShift() - GetShift())}; + offset = Common::AlignDown(offset, diff); + if (bitmap.ClearRange(offset, diff)) { + return heap_address + (offset << GetShift()); + } + } + + // We couldn't coalesce, or we're already as big as possible + return 0; + } + + VAddr PopBlock(bool random) { + // Find a free block + const s64 soffset{bitmap.FindFreeBlock(random)}; + if (soffset < 0) { + return 0; + } + const auto offset{static_cast<std::size_t>(soffset)}; + + // Update our tracking and return it + bitmap.ClearBit(offset); + return heap_address + (offset << GetShift()); + } + + public: + static constexpr std::size_t CalculateManagementOverheadSize(std::size_t region_size, + std::size_t cur_block_shift, + std::size_t next_block_shift) { + const auto cur_block_size{(1ULL << cur_block_shift)}; + const auto next_block_size{(1ULL << next_block_shift)}; + const auto align{(next_block_shift != 0) ? next_block_size : cur_block_size}; + return KPageBitmap::CalculateManagementOverheadSize( + (align * 2 + Common::AlignUp(region_size, align)) / cur_block_size); + } + }; + +public: + KPageHeap() = default; + + constexpr VAddr GetAddress() const { + return heap_address; + } + constexpr std::size_t GetSize() const { + return heap_size; + } + constexpr VAddr GetEndAddress() const { + return GetAddress() + GetSize(); + } + constexpr std::size_t GetPageOffset(VAddr block) const { + return (block - GetAddress()) / PageSize; + } + + void Initialize(VAddr heap_address, std::size_t heap_size, std::size_t metadata_size); + VAddr AllocateBlock(s32 index, bool random); + void Free(VAddr addr, std::size_t num_pages); + + void UpdateUsedSize() { + used_size = heap_size - (GetNumFreePages() * PageSize); + } + + static std::size_t CalculateManagementOverheadSize(std::size_t region_size); + +private: + constexpr std::size_t GetNumFreePages() const { + std::size_t num_free{}; + + for (const auto& block : blocks) { + num_free += block.GetNumFreePages(); + } + + return num_free; + } + + void FreeBlock(VAddr block, s32 index); + + VAddr heap_address{}; + std::size_t heap_size{}; + std::size_t used_size{}; + std::array<Block, NumMemoryBlockPageShifts> blocks{}; + std::vector<u64> metadata; +}; + +} // namespace Kernel |