dolphin/Source/Core/Common/MemArena.cpp

163 lines
3.6 KiB
C++

// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.
#include <cstddef>
#include <cstdlib>
#include <set>
#include <string>
#include "Common/CommonFuncs.h"
#include "Common/CommonTypes.h"
#include "Common/Logging/Log.h"
#include "Common/MemArena.h"
#include "Common/MsgHandler.h"
#include "Common/StringUtil.h"
#ifdef _WIN32
#include <windows.h>
#else
#include <cerrno>
#include <cstring>
#include <fcntl.h>
#include <sys/mman.h>
#include <unistd.h>
#ifdef ANDROID
#include <linux/ashmem.h>
#include <sys/ioctl.h>
#endif
#endif
#ifdef ANDROID
#define ASHMEM_DEVICE "/dev/ashmem"
static int AshmemCreateFileMapping(const char* name, size_t size)
{
int fd, ret;
fd = open(ASHMEM_DEVICE, O_RDWR);
if (fd < 0)
return fd;
// We don't really care if we can't set the name, it is optional
ioctl(fd, ASHMEM_SET_NAME, name);
ret = ioctl(fd, ASHMEM_SET_SIZE, size);
if (ret < 0)
{
close(fd);
NOTICE_LOG(MEMMAP, "Ashmem returned error: 0x%08x", ret);
return ret;
}
return fd;
}
#endif
void MemArena::GrabSHMSegment(size_t size)
{
#ifdef _WIN32
hMemoryMapping =
CreateFileMapping(INVALID_HANDLE_VALUE, nullptr, PAGE_READWRITE, 0, (DWORD)(size), nullptr);
#elif defined(ANDROID)
fd = AshmemCreateFileMapping("Dolphin-emu", size);
if (fd < 0)
{
NOTICE_LOG(MEMMAP, "Ashmem allocation failed");
return;
}
#else
for (int i = 0; i < 10000; i++)
{
std::string file_name = StringFromFormat("/dolphinmem.%d", i);
fd = shm_open(file_name.c_str(), O_RDWR | O_CREAT | O_EXCL, 0600);
if (fd != -1)
{
shm_unlink(file_name.c_str());
break;
}
else if (errno != EEXIST)
{
ERROR_LOG(MEMMAP, "shm_open failed: %s", strerror(errno));
return;
}
}
if (ftruncate(fd, size) < 0)
ERROR_LOG(MEMMAP, "Failed to allocate low memory space");
#endif
}
void MemArena::ReleaseSHMSegment()
{
#ifdef _WIN32
CloseHandle(hMemoryMapping);
hMemoryMapping = 0;
#else
close(fd);
#endif
}
void* MemArena::CreateView(s64 offset, size_t size, void* base)
{
#ifdef _WIN32
return MapViewOfFileEx(hMemoryMapping, FILE_MAP_ALL_ACCESS, 0, (DWORD)((u64)offset), size, base);
#else
void* retval = mmap(base, size, PROT_READ | PROT_WRITE,
MAP_SHARED | ((base == nullptr) ? 0 : MAP_FIXED), fd, offset);
if (retval == MAP_FAILED)
{
NOTICE_LOG(MEMMAP, "mmap failed");
return nullptr;
}
else
{
return retval;
}
#endif
}
void MemArena::ReleaseView(void* view, size_t size)
{
#ifdef _WIN32
UnmapViewOfFile(view);
#else
munmap(view, size);
#endif
}
u8* MemArena::FindMemoryBase()
{
#if _ARCH_32
const size_t memory_size = 0x31000000;
#else
const size_t memory_size = 0x400000000;
#endif
#ifdef _WIN32
u8* base = static_cast<u8*>(VirtualAlloc(nullptr, memory_size, MEM_RESERVE, PAGE_READWRITE));
if (!base)
{
PanicAlert("Failed to map enough memory space: %s", GetLastErrorMsg().c_str());
return nullptr;
}
VirtualFree(base, 0, MEM_RELEASE);
return base;
#else
#ifdef ANDROID
// Android 4.3 changed how mmap works.
// if we map it private and then munmap it, we can't use the base returned.
// This may be due to changes in them support a full SELinux implementation.
const int flags = MAP_ANON | MAP_SHARED;
#else
const int flags = MAP_ANON | MAP_PRIVATE;
#endif
void* base = mmap(nullptr, memory_size, PROT_NONE, flags, -1, 0);
if (base == MAP_FAILED)
{
PanicAlert("Failed to map enough memory space: %s", GetLastErrorMsg().c_str());
return nullptr;
}
munmap(base, memory_size);
return static_cast<u8*>(base);
#endif
}