dolphin/Source/Core/Common/MemoryUtil.cpp

293 lines
7.9 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
#include "Common/MemoryUtil.h"
#include <cstddef>
#include <cstdlib>
#include <string>
#include "Common/CommonFuncs.h"
#include "Common/CommonTypes.h"
#include "Common/Logging/Log.h"
#include "Common/MsgHandler.h"
#ifdef _WIN32
#include <windows.h>
#include "Common/StringUtil.h"
#else
#include <pthread.h>
#include <stdio.h>
#include <sys/mman.h>
#include <sys/types.h>
#if defined __APPLE__ || defined __FreeBSD__ || defined __OpenBSD__ || defined __NetBSD__
#include <sys/sysctl.h>
#elif defined __HAIKU__
#include <OS.h>
#else
#include <sys/sysinfo.h>
#endif
#endif
namespace Common
{
// This is purposely not a full wrapper for virtualalloc/mmap, but it
// provides exactly the primitive operations that Dolphin needs.
void* AllocateExecutableMemory(size_t size)
{
#if defined(_WIN32)
void* ptr = VirtualAlloc(nullptr, size, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
#else
int map_flags = MAP_ANON | MAP_PRIVATE;
#if defined(__APPLE__)
map_flags |= MAP_JIT;
#endif
void* ptr = mmap(nullptr, size, PROT_READ | PROT_WRITE | PROT_EXEC, map_flags, -1, 0);
if (ptr == MAP_FAILED)
ptr = nullptr;
#endif
if (ptr == nullptr)
PanicAlertFmt("Failed to allocate executable memory");
return ptr;
}
// This function is used to provide a counter for the JITPageWrite*Execute*
// functions to enable nesting. The static variable is wrapped in a a function
// to allow those functions to be called inside of the constructor of a static
// variable portably.
//
// The variable is thread_local as the W^X mode is specific to each running thread.
static int& JITPageWriteNestCounter()
{
static thread_local int nest_counter = 0;
return nest_counter;
}
// Certain platforms (Mac OS on ARM) enforce that a single thread can only have write or
// execute permissions to pages at any given point of time. The two below functions
// are used to toggle between having write permissions or execute permissions.
//
// The default state of these allocations in Dolphin is for them to be executable,
// but not writeable. So, functions that are updating these pages should wrap their
// writes like below:
// JITPageWriteEnableExecuteDisable();
// PrepareInstructionStreamForJIT();
// JITPageWriteDisableExecuteEnable();
// These functions can be nested, in which case execution will only be enabled
// after the call to the JITPageWriteDisableExecuteEnable from the top most
// nesting level. Example:
// [JIT page is in execute mode for the thread]
// JITPageWriteEnableExecuteDisable();
// [JIT page is in write mode for the thread]
// JITPageWriteEnableExecuteDisable();
// [JIT page is in write mode for the thread]
// JITPageWriteDisableExecuteEnable();
// [JIT page is in write mode for the thread]
// JITPageWriteDisableExecuteEnable();
// [JIT page is in execute mode for the thread]
// Allows a thread to write to executable memory, but not execute the data.
void JITPageWriteEnableExecuteDisable()
{
#if defined(_M_ARM_64) && defined(__APPLE__)
if (JITPageWriteNestCounter() == 0)
{
if (__builtin_available(macOS 11.0, *))
{
pthread_jit_write_protect_np(0);
}
}
#endif
JITPageWriteNestCounter()++;
}
// Allows a thread to execute memory allocated for execution, but not write to it.
void JITPageWriteDisableExecuteEnable()
{
JITPageWriteNestCounter()--;
// Sanity check the NestCounter to identify underflow
// This can indicate the calls to JITPageWriteDisableExecuteEnable()
// are not matched with previous calls to JITPageWriteEnableExecuteDisable()
if (JITPageWriteNestCounter() < 0)
PanicAlertFmt("JITPageWriteNestCounter() underflowed");
#if defined(_M_ARM_64) && defined(__APPLE__)
if (JITPageWriteNestCounter() == 0)
{
if (__builtin_available(macOS 11.0, *))
{
pthread_jit_write_protect_np(1);
}
}
#endif
}
void* AllocateMemoryPages(size_t size)
{
#ifdef _WIN32
void* ptr = VirtualAlloc(nullptr, size, MEM_COMMIT, PAGE_READWRITE);
#else
void* ptr = mmap(nullptr, size, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
if (ptr == MAP_FAILED)
ptr = nullptr;
#endif
if (ptr == nullptr)
PanicAlertFmt("Failed to allocate raw memory");
return ptr;
}
void* AllocateAlignedMemory(size_t size, size_t alignment)
{
#ifdef _WIN32
void* ptr = _aligned_malloc(size, alignment);
#else
void* ptr = nullptr;
if (posix_memalign(&ptr, alignment, size) != 0)
ERROR_LOG_FMT(MEMMAP, "Failed to allocate aligned memory");
#endif
if (ptr == nullptr)
PanicAlertFmt("Failed to allocate aligned memory");
return ptr;
}
bool FreeMemoryPages(void* ptr, size_t size)
{
if (ptr)
{
#ifdef _WIN32
if (!VirtualFree(ptr, 0, MEM_RELEASE))
{
PanicAlertFmt("FreeMemoryPages failed!\nVirtualFree: {}", GetLastErrorString());
return false;
}
#else
if (munmap(ptr, size) != 0)
{
PanicAlertFmt("FreeMemoryPages failed!\nmunmap: {}", LastStrerrorString());
return false;
}
#endif
}
return true;
}
void FreeAlignedMemory(void* ptr)
{
if (ptr)
{
#ifdef _WIN32
_aligned_free(ptr);
#else
free(ptr);
#endif
}
}
bool ReadProtectMemory(void* ptr, size_t size)
{
#ifdef _WIN32
DWORD oldValue;
if (!VirtualProtect(ptr, size, PAGE_NOACCESS, &oldValue))
{
PanicAlertFmt("ReadProtectMemory failed!\nVirtualProtect: {}", GetLastErrorString());
return false;
}
#else
if (mprotect(ptr, size, PROT_NONE) != 0)
{
PanicAlertFmt("ReadProtectMemory failed!\nmprotect: {}", LastStrerrorString());
return false;
}
#endif
return true;
}
bool WriteProtectMemory(void* ptr, size_t size, bool allowExecute)
{
#ifdef _WIN32
DWORD oldValue;
if (!VirtualProtect(ptr, size, allowExecute ? PAGE_EXECUTE_READ : PAGE_READONLY, &oldValue))
{
PanicAlertFmt("WriteProtectMemory failed!\nVirtualProtect: {}", GetLastErrorString());
return false;
}
#elif !(defined(_M_ARM_64) && defined(__APPLE__))
// MacOS 11.2 on ARM does not allow for changing the access permissions of pages
// that were marked executable, instead it uses the protections offered by MAP_JIT
// for write protection.
if (mprotect(ptr, size, allowExecute ? (PROT_READ | PROT_EXEC) : PROT_READ) != 0)
{
PanicAlertFmt("WriteProtectMemory failed!\nmprotect: {}", LastStrerrorString());
return false;
}
#endif
return true;
}
bool UnWriteProtectMemory(void* ptr, size_t size, bool allowExecute)
{
#ifdef _WIN32
DWORD oldValue;
if (!VirtualProtect(ptr, size, allowExecute ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE, &oldValue))
{
PanicAlertFmt("UnWriteProtectMemory failed!\nVirtualProtect: {}", GetLastErrorString());
return false;
}
#elif !(defined(_M_ARM_64) && defined(__APPLE__))
// MacOS 11.2 on ARM does not allow for changing the access permissions of pages
// that were marked executable, instead it uses the protections offered by MAP_JIT
// for write protection.
if (mprotect(ptr, size,
allowExecute ? (PROT_READ | PROT_WRITE | PROT_EXEC) : PROT_WRITE | PROT_READ) != 0)
{
PanicAlertFmt("UnWriteProtectMemory failed!\nmprotect: {}", LastStrerrorString());
return false;
}
#endif
return true;
}
size_t MemPhysical()
{
#ifdef _WIN32
MEMORYSTATUSEX memInfo;
memInfo.dwLength = sizeof(MEMORYSTATUSEX);
GlobalMemoryStatusEx(&memInfo);
return memInfo.ullTotalPhys;
#elif defined __APPLE__ || defined __FreeBSD__ || defined __OpenBSD__ || defined __NetBSD__
int mib[2];
size_t physical_memory;
mib[0] = CTL_HW;
#ifdef __APPLE__
mib[1] = HW_MEMSIZE;
#elif defined __FreeBSD__
mib[1] = HW_REALMEM;
#elif defined __OpenBSD__ || defined __NetBSD__
mib[1] = HW_PHYSMEM64;
#endif
size_t length = sizeof(size_t);
sysctl(mib, 2, &physical_memory, &length, nullptr, 0);
return physical_memory;
#elif defined __HAIKU__
system_info sysinfo;
get_system_info(&sysinfo);
return static_cast<size_t>(sysinfo.max_pages * B_PAGE_SIZE);
#else
struct sysinfo memInfo;
sysinfo(&memInfo);
return (size_t)memInfo.totalram * memInfo.mem_unit;
#endif
}
} // namespace Common