ppsspp/Common/MemArenaPosix.cpp
Henrik Rydgård 1d528d6f3b Linux: Port the proper memory base finding over to MemArenaPosix.cpp.
Who knows, might fix some crashes.
2019-09-01 17:10:13 +02:00

139 lines
4.3 KiB
C++

// Copyright (C) 2003 Dolphin Project.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0 or later versions.
// This program is distributed in the hope that 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 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/
#include "ppsspp_config.h"
#if !defined(_WIN32) && !defined(ANDROID) && !defined(__APPLE__)
#include <string>
#include "FileUtil.h"
#include "MemoryUtil.h"
#include "MemArena.h"
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <cerrno>
#include <cstring>
static const std::string tmpfs_location = "/dev/shm";
static const std::string tmpfs_ram_temp_file = "/dev/shm/gc_mem.tmp";
// do not make this "static"
std::string ram_temp_file = "/tmp/gc_mem.tmp";
size_t MemArena::roundup(size_t x) {
return x;
}
bool MemArena::NeedsProbing() {
return false;
}
void MemArena::GrabLowMemSpace(size_t size) {
mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
// Some platforms (like Raspberry Pi) end up flushing to disk.
// To avoid this, we try to use /dev/shm (tmpfs) if it exists.
fd = -1;
if (File::Exists(tmpfs_location)) {
fd = open(tmpfs_ram_temp_file.c_str(), O_RDWR | O_CREAT, mode);
if (fd >= 0) {
// Great, this definitely shouldn't flush to disk.
ram_temp_file = tmpfs_ram_temp_file;
}
}
if (fd < 0) {
fd = open(ram_temp_file.c_str(), O_RDWR | O_CREAT, mode);
}
if (fd < 0) {
ERROR_LOG(MEMMAP, "Failed to grab memory space as a file: %s of size: %08x errno: %d", ram_temp_file.c_str(), (int)size, (int)(errno));
return;
}
// delete immediately, we keep the fd so it still lives
if (unlink(ram_temp_file.c_str()) != 0) {
WARN_LOG(MEMMAP, "Failed to unlink %s", ram_temp_file.c_str());
}
if (ftruncate(fd, size) != 0) {
ERROR_LOG(MEMMAP, "Failed to ftruncate %d (%s) to size %08x", (int)fd, ram_temp_file.c_str(), (int)size);
}
return;
}
void MemArena::ReleaseSpace() {
close(fd);
}
void *MemArena::CreateView(s64 offset, size_t size, void *base)
{
void *retval = mmap(base, size, PROT_READ | PROT_WRITE, MAP_SHARED |
// Do not sync memory to underlying file. Linux has this by default.
#if defined(__DragonFly__) || defined(__FreeBSD__)
MAP_NOSYNC |
#endif
((base == 0) ? 0 : MAP_FIXED), fd, offset);
if (retval == MAP_FAILED) {
NOTICE_LOG(MEMMAP, "mmap on %s (fd: %d) failed", ram_temp_file.c_str(), (int)fd);
return 0;
}
return retval;
}
void MemArena::ReleaseView(void* view, size_t size) {
munmap(view, size);
}
u8* MemArena::Find4GBBase() {
// Now, create views in high memory where there's plenty of space.
#if PPSSPP_ARCH(64BIT) && !defined(USE_ADDRESS_SANITIZER)
// We should probably just go look in /proc/self/maps for some free space.
// But let's try the anonymous mmap trick, just like on 32-bit, but bigger and
// aligned to 4GB for the movk trick. We can ensure that we get an aligned 4GB
// address by grabbing 8GB and aligning the pointer.
const uint64_t EIGHT_GIGS = 0x200000000ULL;
void *base = mmap(0, EIGHT_GIGS, PROT_READ | PROT_WRITE, MAP_ANON | MAP_SHARED, -1, 0);
if (base) {
INFO_LOG(MEMMAP, "base: %p", base);
uint64_t aligned_base = ((uint64_t)base + 0xFFFFFFFF) & ~0xFFFFFFFFULL;
INFO_LOG(MEMMAP, "aligned_base: %p", (void *)aligned_base);
munmap(base, EIGHT_GIGS);
return reinterpret_cast<u8 *>(aligned_base);
} else {
u8 *hardcoded_ptr = reinterpret_cast<u8*>(0x2300000000ULL);
INFO_LOG(MEMMAP, "Failed to anonymously map 8GB. Fall back to the hardcoded pointer %p.", hardcoded_ptr);
// Just grab some random 4GB...
// This has been known to fail lately though, see issue #12249.
return hardcoded_ptr;
}
#else
size_t size = 0x10000000;
void* base = mmap(0, size, PROT_READ | PROT_WRITE,
MAP_ANON | MAP_SHARED, -1, 0);
if (base == MAP_FAILED) {
PanicAlert("Failed to map 256 MB of memory space: %s", strerror(errno));
return 0;
}
munmap(base, size);
return static_cast<u8*>(base);
#endif
}
#endif