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suyu/src/common/multi_level_page_table.inc
2022-10-06 21:00:53 +02:00

85 lines
2.5 KiB
C++

// Copyright 2021 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#ifdef _WIN32
#include <windows.h>
#else
#include <sys/mman.h>
#endif
#include "common/assert.h"
#include "common/multi_level_page_table.h"
namespace Common {
template <typename BaseAddr>
MultiLevelPageTable<BaseAddr>::MultiLevelPageTable(std::size_t address_space_bits_,
std::size_t first_level_bits_,
std::size_t page_bits_)
: address_space_bits{address_space_bits_},
first_level_bits{first_level_bits_}, page_bits{page_bits_} {
if (page_bits == 0) {
return;
}
first_level_shift = address_space_bits - first_level_bits;
first_level_chunk_size = (1ULL << (first_level_shift - page_bits)) * sizeof(BaseAddr);
alloc_size = (1ULL << (address_space_bits - page_bits)) * sizeof(BaseAddr);
std::size_t first_level_size = 1ULL << first_level_bits;
first_level_map.resize(first_level_size, nullptr);
#ifdef _WIN32
void* base{VirtualAlloc(nullptr, alloc_size, MEM_RESERVE, PAGE_READWRITE)};
#else
void* base{mmap(nullptr, alloc_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0)};
if (base == MAP_FAILED) {
base = nullptr;
}
#endif
ASSERT(base);
base_ptr = reinterpret_cast<BaseAddr*>(base);
}
template <typename BaseAddr>
MultiLevelPageTable<BaseAddr>::~MultiLevelPageTable() noexcept {
if (!base_ptr) {
return;
}
#ifdef _WIN32
ASSERT(VirtualFree(base_ptr, 0, MEM_RELEASE));
#else
ASSERT(munmap(base_ptr, alloc_size) == 0);
#endif
}
template <typename BaseAddr>
void MultiLevelPageTable<BaseAddr>::ReserveRange(u64 start, std::size_t size) {
const u64 new_start = start >> first_level_shift;
const u64 new_end = (start + size) >> first_level_shift;
for (u64 i = new_start; i <= new_end; i++) {
if (!first_level_map[i]) {
AllocateLevel(i);
}
}
}
template <typename BaseAddr>
void MultiLevelPageTable<BaseAddr>::AllocateLevel(u64 level) {
void* ptr = reinterpret_cast<char *>(base_ptr) + level * first_level_chunk_size;
#ifdef _WIN32
void* base{VirtualAlloc(ptr, first_level_chunk_size, MEM_COMMIT, PAGE_READWRITE)};
#else
void* base{mmap(ptr, first_level_chunk_size, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0)};
if (base == MAP_FAILED) {
base = nullptr;
}
#endif
ASSERT(base);
first_level_map[level] = base;
}
} // namespace Common