/* PCSX2 - PS2 Emulator for PCs
* Copyright (C) 2002-2010 PCSX2 Dev Team
*
* PCSX2 is free software: you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* PCSX2 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 for more details.
*
* You should have received a copy of the GNU General Public License along with PCSX2.
* If not, see .
*/
#if !defined(_WIN32)
#include
#include
#include
#include
#include
#include
#include "fmt/core.h"
#include "common/Align.h"
#include "common/PageFaultSource.h"
#include "common/Assertions.h"
#include "common/Console.h"
#include "common/Exceptions.h"
// Apple uses the MAP_ANON define instead of MAP_ANONYMOUS, but they mean
// the same thing.
#if defined(__APPLE__) && !defined(MAP_ANONYMOUS)
#define MAP_ANONYMOUS MAP_ANON
#endif
#include
#include
#include
#include
#ifndef __APPLE__
#include
#endif
extern void SignalExit(int sig);
static const uptr m_pagemask = getpagesize() - 1;
#if defined(__APPLE__)
static struct sigaction s_old_sigbus_action;
#else
static struct sigaction s_old_sigsegv_action;
#endif
// Linux implementation of SIGSEGV handler. Bind it using sigaction().
static void SysPageFaultSignalFilter(int signal, siginfo_t* siginfo, void* ctx)
{
// [TODO] : Add a thread ID filter to the Linux Signal handler here.
// Rationale: On windows, the __try/__except model allows per-thread specific behavior
// for page fault handling. On linux, there is a single signal handler for the whole
// process, but the handler is executed by the thread that caused the exception.
// Stdio Usage note: SIGSEGV handling is a synchronous in-thread signal. It is done
// from the context of the current thread and stackframe. So long as the thread is not
// the main/ui thread, use of the px assertion system should be safe. Use of stdio should
// be safe even on the main thread.
// (in other words, stdio limitations only really apply to process-level asynchronous
// signals)
// Note: Use of stdio functions isn't safe here. Avoid console logs,
// assertions, file logs, or just about anything else useful.
#if defined(__APPLE__) && defined(__x86_64__)
void* const exception_pc = reinterpret_cast(static_cast(ctx)->uc_mcontext->__ss.__rip);
#elif defined(__x86_64__)
void* const exception_pc = reinterpret_cast(static_cast(ctx)->uc_mcontext.gregs[REG_RIP]);
#else
void* const exception_pc = nullptr;
#endif
// Note: This signal can be accessed by the EE or MTVU thread
// Source_PageFault is a global variable with its own state information
// so for now we lock this exception code unless someone can fix this better...
std::unique_lock lock(PageFault_Mutex);
Source_PageFault->Dispatch(PageFaultInfo((uptr)exception_pc, (uptr)siginfo->si_addr & ~m_pagemask));
// resumes execution right where we left off (re-executes instruction that
// caused the SIGSEGV).
if (Source_PageFault->WasHandled())
return;
std::fprintf(stderr, "Unhandled page fault @ 0x%08x", siginfo->si_addr);
pxFailRel("Unhandled page fault");
}
void _platform_InstallSignalHandler()
{
Console.WriteLn("Installing POSIX SIGSEGV handler...");
struct sigaction sa;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_SIGINFO;
sa.sa_sigaction = SysPageFaultSignalFilter;
#if defined(__APPLE__)
// MacOS uses SIGBUS for memory permission violations
sigaction(SIGBUS, &sa, &s_old_sigbus_action);
#else
sigaction(SIGSEGV, &sa, &s_old_sigsegv_action);
#endif
}
static __ri uint LinuxProt(const PageProtectionMode& mode)
{
u32 lnxmode = 0;
if (mode.CanWrite())
lnxmode |= PROT_WRITE;
if (mode.CanRead())
lnxmode |= PROT_READ;
if (mode.CanExecute())
lnxmode |= PROT_EXEC | PROT_READ;
return lnxmode;
}
void* HostSys::Mmap(void* base, size_t size, const PageProtectionMode& mode)
{
pxAssertDev((size & (__pagesize - 1)) == 0, "Size is page aligned");
if (mode.IsNone())
return nullptr;
const u32 prot = LinuxProt(mode);
u32 flags = MAP_PRIVATE | MAP_ANONYMOUS;
if (base)
flags |= MAP_FIXED;
void* res = mmap(base, size, prot, flags, -1, 0);
if (res == MAP_FAILED)
return nullptr;
return res;
}
void HostSys::Munmap(void* base, size_t size)
{
if (!base)
return;
munmap((void*)base, size);
}
void HostSys::MemProtect(void* baseaddr, size_t size, const PageProtectionMode& mode)
{
pxAssertDev((size & (__pagesize - 1)) == 0, "Size is page aligned");
const u32 lnxmode = LinuxProt(mode);
const int result = mprotect(baseaddr, size, lnxmode);
if (result != 0)
pxFail("mprotect() failed");
}
std::string HostSys::GetFileMappingName(const char* prefix)
{
const unsigned pid = static_cast(getpid());
#if defined(__FreeBSD__)
// FreeBSD's shm_open(3) requires name to be absolute
return fmt::format("/tmp/{}_{}", prefix, pid);
#else
return fmt::format("{}_{}", prefix, pid);
#endif
}
void* HostSys::CreateSharedMemory(const char* name, size_t size)
{
const int fd = shm_open(name, O_CREAT | O_EXCL | O_RDWR, 0600);
if (fd < 0)
{
std::fprintf(stderr, "shm_open failed: %d\n", errno);
return nullptr;
}
// we're not going to be opening this mapping in other processes, so remove the file
shm_unlink(name);
// ensure it's the correct size
#if !defined(__APPLE__) && !defined(__FreeBSD__)
if (ftruncate64(fd, static_cast(size)) < 0)
#else
if (ftruncate(fd, static_cast(size)) < 0)
#endif
{
std::fprintf(stderr, "ftruncate64(%zu) failed: %d\n", size, errno);
return nullptr;
}
return reinterpret_cast(static_cast(fd));
}
void HostSys::DestroySharedMemory(void* ptr)
{
close(static_cast(reinterpret_cast(ptr)));
}
void* HostSys::MapSharedMemory(void* handle, size_t offset, void* baseaddr, size_t size, const PageProtectionMode& mode)
{
const uint lnxmode = LinuxProt(mode);
const int flags = (baseaddr != nullptr) ? (MAP_SHARED | MAP_FIXED) : MAP_SHARED;
void* ptr = mmap(baseaddr, size, lnxmode, flags, static_cast(reinterpret_cast(handle)), static_cast(offset));
if (ptr == MAP_FAILED)
return nullptr;
return ptr;
}
void HostSys::UnmapSharedMemory(void* baseaddr, size_t size)
{
if (mmap(baseaddr, size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0) == MAP_FAILED)
pxFailRel("Failed to unmap shared memory");
}
SharedMemoryMappingArea::SharedMemoryMappingArea(u8* base_ptr, size_t size, size_t num_pages)
: m_base_ptr(base_ptr)
, m_size(size)
, m_num_pages(num_pages)
{
}
SharedMemoryMappingArea::~SharedMemoryMappingArea()
{
pxAssertRel(m_num_mappings == 0, "No mappings left");
if (munmap(m_base_ptr, m_size) != 0)
pxFailRel("Failed to release shared memory area");
}
std::unique_ptr SharedMemoryMappingArea::Create(size_t size)
{
pxAssertRel(Common::IsAlignedPow2(size, __pagesize), "Size is page aligned");
void* alloc = mmap(nullptr, size, PROT_NONE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
if (alloc == MAP_FAILED)
return nullptr;
return std::unique_ptr(new SharedMemoryMappingArea(static_cast(alloc), size, size / __pagesize));
}
u8* SharedMemoryMappingArea::Map(void* file_handle, size_t file_offset, void* map_base, size_t map_size, const PageProtectionMode& mode)
{
pxAssert(static_cast(map_base) >= m_base_ptr && static_cast(map_base) < (m_base_ptr + m_size));
const uint lnxmode = LinuxProt(mode);
void* const ptr = mmap(map_base, map_size, lnxmode, MAP_SHARED | MAP_FIXED,
static_cast(reinterpret_cast(file_handle)), static_cast(file_offset));
if (ptr == MAP_FAILED)
return nullptr;
m_num_mappings++;
return static_cast(ptr);
}
bool SharedMemoryMappingArea::Unmap(void* map_base, size_t map_size)
{
pxAssert(static_cast(map_base) >= m_base_ptr && static_cast(map_base) < (m_base_ptr + m_size));
if (mmap(map_base, map_size, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0) == MAP_FAILED)
return false;
m_num_mappings--;
return true;
}
#endif